Fire and Rain= Mudslides. My Winter Outlook Snow Forecast

Standing Wave Clouds
This is the visible satellite image from 9:30am. It shows the distinct result of cold air rolling down from the hills and mountains to our west, and drying out. the ripples are the result of the air rolling up and down over the terrain. The more 'down' the air flows, the clouds thin out and eventually fall apart. The clouds appear to look like waves or ripples in a pond. While it was clear at Baltimore's Inner Harbor, half of our sky was covered in clouds, and just 15 miles west it was overcast. As the sun warms, mixes and destabilizes the air, more clouds will develop east of this line, and appear to shift it over the city. There still may be a flurry west of the city.


The National Weather Map shows two distinct problems, while the rest of the country catches a break.
Great Lakes snow will continue, even after throwing a stray flurry nearby today.
California has taken it on the chin this month. Record heat, wild fires, and now heavy rain. The result is a formula for mudslides. The ground can not handle the rain. The steep terrain and run off will cause problems today, but improve tomorrow.
A little piece of this will move east, but our next storm does not look impressive. In fact, I am going to jump past any flurry chance today and the light showers on Friday. The back end of the holiday could get interesting. A few days ago, I mentioned Larry Cosgrove's forecast for a coastal storm early next week. The GFS model did not have it, but it is not the best long range forecaster. However, it is what most of you see in one form or another in your long range forecasts. It did catch on to it last night. Below are just a few samples of what may happen from a few different views.
The Navy NOGAPS model does have a coast storm strengthen after passing north of Maryland Monday morning. The blue line would be the snow line, and is still too far west. This represents the cold air NOT catching up with the precipitation. The storm will dump heavy snow in New England, but NOGAPS has us with Sunday night rain, ending Monday morning, with maybe a flurry Monday evening, then clearing out.



The ECMWF or European model here shows Sunday nights map. The Low in the Great Lakes will shift energy to a developing low along the 'triple point' as it occludes. That basically means the cold air cuts off the circulation and a new storm forms. This secondary storm would not take form until Monday and after it has a chance to pass us by. Again, a near miss for us...
My trusted Canadian model does not show it either... Here is that same Great Lakes Low Sunday night into Monday.
so what to do, what to do?
There has been a tendency this season for the cold air to build farther south, and the timing of this systems mid range to be off.

So far, I have not seen much support for much of anything next week. Then the dark horse gallops back into the picture... The GFS..
Here is Sunday night's transfer of energy to the developing coastal. It may be hard to see, but the GFS has it farther south and east than any other model. Here is the low east of Ocean City, with the famed 540 thickness line (snow line in white) near I-95. That is contrary to what I showed above. The cold air DOES catch up to the precipitation. That would be a change over from rain to snow- but it looks light for now. This happens because it takes the cold air all the way down to the Gulf Coast, and allows the jet stream to buckle. This gets the cold air in here, while keeping the system closer to us.
Behind it is yet another, but strong storm off the coast. This is Monday night, along a very strong conveyor belt of energy and moisture aligned with the Gulf Stream. This might be too far away, but holding on to Larry Cosgrove's notion of something impressive.
I have cut out most of the technical stuff, and just tried to show the basic idea of what many of the models are doing or not doing. There is still a small glimmer of hope for snow lovers, and enough of a chance to warrant some attention on the holiday weekend. I thought I would take a little break- even though I have to work through Saturday. So if I see anything interesting pop up, I'll post it. Otherwise, it's just a matter of watching how this might unfold. The first order would be to gauge the Friday system. While it weakens, it should set up the next round of cold air. Depending on how that air mass builds south, could determine how the rest of the dominoes fall. Stay tuned....
{More Later}

Keep your Eyes on the Prize

Yesterday we reached 71F without the sun! That was an impressive show, thanks to strong southerly winds that gusted over 40mph. There were some trees down this morning, but that Tornado Watch thankfully did not result in any twisters- as of this posting (6am). The air pressure at BWI dropped to 29.47" or 997 mb on the barometer. That is mighty low and the main reason for our strong winds. However it only resulted in .38" of rain up through 6am this morning. That is well under the expected 1 inch or more. It sure sounded like more!
The strength of this storm will help to establish a little blocking as it winds up in eastern Canada in the next few days. That is a pattern that allow colder air to spill down the east coast. That will set the stage for an eastward push of our next storm. Before I get to that...
Spotlight: St. Louis, MO
Monday: High temperature 79F
Tuesday: Snowfall= 10 inches. A record for the date!

Now we can focus on the next storm for Friday and Saturday:
Here is the GFS projection for late Saturday. As you can see an impressive Low Pressure of 992mb will be passing off of the coast to our east. The 540 thickness line that we watch for rain/snow is highlighted in white. The strong northerly wind direction should allow some backlash moisture to survive as the cold air catches up. Here it does appear to have the chance of bringing a few hours of snowfall. The question that will arise is "can it stick"?
I would suggest now that would be based on timing. The higher sun angle, and recent warm stretch will hurt the chances of 'stickage' during the daylight hours. So while there will be a lot of talk about how much we can get- I can't go there. At least not now. If the timing changes, and we end up with overnight snow- then we could expect to talk amounts.
On that note, here is the Canadian model also showing a turn over back to snow on Saturday: You can see that the surface Low is a little faster, which would result in less moisture left over for snow- but could signal a chance of the whole pattern turning sooner or earlier in the day. Something to watch:
Surface Pressure Precipitation (6hr total)

Rolling out the 'white' carpet...

Just a little bit of snow to wet your pallet. More importantly, it will establish a base for the arctic air mass, and lock it in longer for the bigger storm.
While temperatures will get near or above freezing, the cold air aloft will guarantee snow and a high ratio. Often we use a base of 10:1. That's 10 inches of snow for 1 inch of liquid. But when you factor in the temperature at cloud level- where the flakes will form...we can get higher ratios with colder temperatures. The overnight models have indicated an average of about -10C or 14F which allows a dryer more 'fluffy' snowflake. For reference, and with the next storm, this 850mb level which is around 5,000Ft up is what I use compared with surface temperatures as a basis for snow, or some form of ice. That is what I see here. I have bumped my total (Now NWS has as well) due to the type of snowflakes.

This reminds me of the December 5th event. It was a similar push south with the final model runs, and that puts the clipper to our south. That usually results in slightly higher amounts of snow because the mountains will not steal the moisture. In fact a little upslope (winds flowing from the ocean up the hills) on the north side will enhance our little Low. The snow will reach it's peak this evening. I would place a general 4pm-10pm for our accumulating snow time frame.
Looking at the primary mid range model extraction for BWI, here is the liquid equivalent for precipitation:
NGM: .04"
AVN/GFS: .13"
NAM: .08"
WRF: .17"
My general forecast: 1-2 inches of snow. However, watching the enhanced radar- it could easily bump up to the next category (2"-4")on my afternoon update. It's looking like a repeat of the December 5th storm.
It may clear our to catch the back half of the total lunar eclipse tonight if we are lucky.

The Friday storm below, but first...

Watch the latest videos on YouTube.com

Sorry I had to post something here for you to view to help the cause. I put one of these on my TV Graphics page, but it gets missed at the bottom.
Before I get to the main event- I want to just touch on my hypothesis on the influence of the moon on our weather. I did mention this yesterday and many times before- and if I pushed a Masters Degree, I would have tested it. However, here we are. A full moon and lunar eclipse tonight, and the two storms are looking stronger. Consider the tidal swing based on the moon, and then translate that to atmospheric (water) and pressure. There also seems to be a connection with geological events as well, and I relate this to influence on magma and plate tectonics. A large 7.4 magnitude earthquake in Indonesia last night prompted tsunami watches around the Indian Ocean. Many large earthquakes in recent memory were within a day of a full or new moon. Including December 26, 2004 in Thailand. It was the same area near Sumatra. Hmmmm. I'd love for someone to pick up this research, or share your thoughts....

The Storm:
I have always hedged my best on the trend of the models. This morning, I see that trend with our clipper and with the main event Friday. Both the Canadian and GFS which I highlighted the other day are showing this. It has turned out to be a busy day for other reasons. This will not be fully in depth, but here's what I've got.
The graphic package was not ready at post time....
Considering the GFS has the best placement of the clipper this morning, I will use it for positioning for Friday. The text output is supporting a change over to ice at least near I-95, as we warm in cloud level (850mb), but stay near or below freezing at the surface. A classic snow/ice line setting up somewhere close. Considering the behavior of today's event staying colder and farther south, I will leave that potential shift for Friday as well. So a forecast of snow to ice, may stay all snow in places. At this point, a good chance for well over 4 inches of snow where it does not change over. However, the ice problem will be bad. I already told a neighbor that she should telecommute on Friday and not drive in... I would put money on school closings, and extended coverage on local TV- Especially here at ABC.
I promise I do more tomorrow.

What goes up, Must Come Down...

"Spinnin' wheel, got to go 'round"- Blood Sweat and Tears.
Another 60's throw back for you Classic Rock fans. Yesterday behaved as expected, except the temperature shot higher (71F-not a record). now we watch the downward slide on the thermometer. I had a conversation with some of the guys at the gym yesterday... we were talking about the big warm ups before some of the historic storms in Baltimore. It is a sign of volatility and atmospheric energy as a ridge that will bring that warm air will be followed by a deeper trough with colder air to feed into a new storm. If you remember something like this- share it in the comment section below.
First thing to watch is how the temperatures behave. I have called for 44F today and 38F tomorrow. If it verifies colder, then the models may not be handling this very well. The cold air will get reinforced by a clipper passing tomorrow afternoon. I have noticed that the trend has pushed it farther south in the past few days. Here is the NAM outlook for Wednesday afternoon. It may not look like much, but it is now poised to give us up to 1 inch of snow as it locks in the arctic air. I do think we have a chance to clear out in time for the Total Lunar Eclipse Wednesday night.

Spinning the wheels for the end of the week, and it looks like your wheels will be spinning on something Friday morning. While there is a tremendous amount of information to digest, I know I have lost some of you with technical overload here. I still plan on getting some of the highlights out, but here is a simplified breakdown for the two primary mid range models I have been following. The Canadian on the right shows an inland track that will likely start as snow Thursday night, but bring ice Friday morning. Depending on the true behavior, this could be a heavy ice event, or eventually turn to rain as the surface low passed just north and west of central Maryland dragging in warmer air. This would be heavier precipiation, but gone Saturday. It does set up a coastal storm for us on Monday.

The GFS model projection here keeps the surface low to our south. That means precipitation will not be as heavy, but stay snow or ice. Little or no rain with this scenario... The GFS does linger snow showers into the weekend with one last burst Sunday morning. It brings another storm (inland runner) our way Tuesday.

Again, this is the over simplified version of what I see now. But I will follow throughout the week. I will introduce more models projections as I see fit, but these will be the benchmarks for how many forecasts will evolve over the week.

Blinded By The Light

"Go-cart Mozart, was checking out the weather chart To see if it was safe outside.."
That's a Manfred Mann tune, which often gets misquoted, but seemed to fit here:
"Blinded by the light, revved up light a deuce, another runner in the night."
Deuce= car
There has been a tremendous amount of buzz about a storm at the end of this week. For time sake I refer you to Mr. Foot's blog who did an extensive analysis of the La Nina, North Atlantic Oscillation, etc.. this past weekend. He may be a little more optimistic than me at this time. The excitement by many may be compounded by a lackluster Maryland winter, and the 5 year anniversary of our #1 snow- record Presidents Week storm in 2003. There are a tremendous amount of pictures and information on the internet of this storm, and I wanted to focus on something different today. Click here for the Feb 17, 2003 radar. Here is a general storm breakdown and comparison.
Anniversary of more big storms:
Among the top 11 snowstorms in Baltimore- 6 have occurred in mid February:
#1: Feb 16-17 2003 28.3"
#3: Feb 11-12 1983 22.8"
#6: Feb 11-14 1899 21.4"
#7: Feb 18-19 1979 20.0"
#8: Feb 15-16 1958 15.5"
#11: Feb 11-12 2006 13.1" (Many have forgotten about this recent storm)

For the regular readers of my blog, you know two main things about me: First- I LOVE SNOW! Second, and most important- I don't like to push the panic button too soon. I have learned a lot in my nearly 2 decade career. Bias can burn you! As good (for those of us that want snow) as something may look 5 days out, things can change. Models change, and all of the ingredients that go into forming a storm may not line up as needed. The more you want snow, you may be blinded by the real data or few models that indicate otherwise. That is my hesitation for Thursday -Saturday's event.
First: the step down in temps will provide a few shots of snow. If you have seen my 7 Day forecast (click the TV Graphics tab above), it looks much more impressive than what will play out.
Tuesday:
Two surface trough shows a step down in temperatures. They may not show up a true cold fronts on the weather map, but these kinks in the isobars will in mark a wind shift and temperature drop.
The 850mb temps(cooling at 5,000Ft) show a drop back to -10C and colder.
The 500mb vorticity max= a spin in the upper levels to help enhance the chance of showers as the cold air builds back in...









Friday Morning:
I am not a one model forecaster, but here is the same GFS model for Friday. For space limitations- I am just showing this one projection... as it does indicate what we will be dealing with. Arctic high may be passing overhead or just north. While that would help with the cold air, it will also be be dry and suppress the phasing branches of the jet stream to our south. Right now it looks like an over running event. That means it could be an extended period, but not an organized blockbuster for us. Over running is when warm moist air ride aloft, and cold air stays at the ground level. That can mean either virga (drying up before hitting the ground) or mixed sleet and freezing rain. This is just a snapshot of the potential, not a guaranteed forecast. Again, I don't like to jump the shark this early until I see how the players are playing. So in the next few days, here are a few things to watch:

1. How cold will it get here. This will show the strength of the new air mass. If we stay in the 30s (BWI) on Wednesday- that is colder than my forecast and a sign it might stay colder.
   
2. Where will the High will be positioned? I see it very close to MD on Thursday. If the center can stay north, or slides past sooner, thigh might allow this storm to slip up the back side and bring in more moisture.
3. When will the High pass? When will the southern branch develop it's Lows? Timing is crucial with this southern branch. If it acts up sooner than Thursday- then it could all pass well to our south. If it develops later than Friday morning, then #1 and #2 will have to be asked differently.

You can also throw in a Full moon on Thursday- and test my hypotheses of enhanced storms thanks to gravity flux. This will be a guarantee to influence coastal regions with above normal high tides. Tomorrow I will start to look at how some other models are handling this event.
"Faith in the flakes."

Groundhog's Day Irony

First a note: Yesterday's official rainfall at BWI was 1.80"- a record for the date, nd the highest 1 day total since October 26th, 2007 when we had 2.49" of rain. That was part of a 4 day total of 5.43" between Oct. 24-27. It's been a while since we had a good soaker. We reached 50F very briefly, but Salisbury hit 63F.

So today is a holiday celebration today actually started as a German Festival 122 years ago. Some consider it to be like Candlemass- the halfway point between the Winter Solstice and Spring Equinox. The original festival ended with the groundhog as the 'main course'... Yummmmmmm.



The irony I see today is that while it is cloudy, Phil 'saw his shadow'. I agree with the forecast of 6 more weeks of winter, but the method is a bit hazy. Perhaps the lights and glare of the camera flashbulbs did it. Either way, we are on the same page. I had mentioned last week of the return of the -NAO, or North Atlantic Blocking pattern that will shift the trough in the jet back along the east coast. There is a lot of energy in this La Nina pattern, and it's just a matter of positioning the jet to benefit us (for snow). While there may be another brief ice event as the next 'rain' storm arrives Monday. This should be our last warm up before the pattern shift. And it will be a warm- into the mid 50s.

Here is the GFS projection for next Friday evening. It does not look like the coastal it tried to spit out yesterday, but the first in a series of clippers as the northern branch of the jetstream becomes more active. This will bring us the chance of snow and lead the charge of dropping the jet farther south with each pass. It will be a week or two process, but I see our return beginning next week and lasting through then end of February at least. Go Phil- I'm with you!




Have you heard of the Golden Snowball Contest in NY State. It's a contest between 5 cities for the highest seasonal snowfall. The latest tally is listed below. As you can see, so far a normal season for them. Below is the National Climate Data Center Summary for snow this season.


Click here for the Northern Hemisphere Snow and Ice Report for 2007-2008 Season.

Refocus the Eyes on the Prize

So we had some morning ice, and a lot of kids/teachers got to sleep in. I didn't do enough to play up the heavy rain.
Here is the Doppler Estimated Rainfall up to 1pm. As of my noon show, the average was 1.00" to 1.50" for the day- and more on the way. Considering that we were down 2" for the year and down 9 inches last year- this is a good thing. I saw large puddle and huge muddy streams rolling down the hills near my house. There is also a lake that has been running very low- this will be a good thing.
As of 2pm- the highest rainfall amounts are listed below. Click here for the Maryland Extreme Weather List, that should be updated hourly. Final totals may jump over 2 inches... and at least bring us back to normal for the year.
Tomorrow we look to Punxsutawney, PA for Phil's Groundhog's Day Prediction. I have a feeling thanks to the clearing behind this storm, he will see his shadow. I'm sure I will see mine, and confirm my call for winter's return. Tomorrow I will show you a long range model call for a coastal storm that some bloggers are already buzzing about.

Outlook Promising- Despite Warmup This Week

It may have been a waste of cold air the past two weeks with very little snow, but we are not done yet. The animation of the Northern Hemisphere shows the 500mb pattern for the past month. The USA is the bottom center section. Look to the right of center (north pole), which is Greenland and the North Atlantic. The blue shows the troughs and old air we have had the past few months. The red shows the increased heights- ridges and warmer air- early in the month- and trying to return again. More below:

Here you can see the graphical breakdown of the NAO- North Atlantic Oscillation. Negative numbers represent a blocking pattern which results in troughs and colder air on the east coast. The GFS forecast shows a this week's positive phase, but a negative phase developing in February. We will be warming up this week, but it's a good thing. The pattern needs to re-establish itself. The recent trough just wasn't producing a good storm track for us. Anything that generated to our south skipped off of the Carolina coast and could not turn the corner north and hit us (like some of us want). Although the Delmarva did get clipped this week. So the forecast for a positive NAO is just for a week, before a return to the cold phase. That will allow another shot of polar air- to set up what will hopefully be more favorable. There is a lot of energy in this La Nina winter- we just need it to reach us the right way. Remember that 8 0f the top 20 Baltimore snowstorms (about 12 inches or more) occurred in February. So while we range from mid 40s to near 50s this week, it's not all bad.

The Chill is on!

While it looks like yesterday's extrapolation from GFS looks to be too cold, it will be frigid. Partially thank the fact that most of our snow melted, and we will likely end up in the mid 20s instead of upper teens in central Maryland today. However, we can expect some single digits temps in the morning. Good thing it's a holiday and a lot of people will get to sleep in. Here you can see this morning's temperatures. I wanted to highlight some spots. First Football: The 3pm Game New England will not be too bad. Boston's 28F this morning however was the same temperature as Pensacola, FL. New Orleans was down to 34F. Note: Atlanta Georgia picked up about 1 inch of snow- but a lot melted on warm ground.
This evening game in Green Bay, WI will be the dangerous one. This morning's temperature ranged from -15F to -20F in northern Wisconsin. Kickoff temperature will be around 0F, with -15F wind chill. That means frostbite can develop in less than 15 minutes. While it might be fun to watch (the Giants win) on TV, it will be dangerous for players and fans.
Tomorrow the beard gets shaved.... but winter is just getting started. Just a quick peak at Tuesday from the Canadian. A cold front will try to reinforce our cold air, and bring us some showers. Right now it looks like snow and or rain showers... but may have the potential of an inch of snow. A series of cold fronts will move through during the week, with a chance of a larger short wave storm next Sunday. More on this Monday.

Snow Burst

No Snow=No Shave: Day 12; Still waiting for 2" @ BWI. check out my Snow Page for more.
Once again, here is the 500mb chart for this afternoon showing the vort max which should generate some strong snow showers. I have timed it out between 11am and 3pm. This is the type of set up that will not like too much until it gets close. Some mid day heating should help enhance the action, and I still expect gusty winds and a coating on the ground in spots.
This may act as a little cold front, although all it will do is slightly shift the wind and allow the skies to clear out tonight cooling us down into the lower 20s. It will, however allow a sunny day to bring us back to normal temps Wednesday.


The outlook for Thursday is still on the fence. While it is looking like that polar air and trough will not truly build in and is holding off until after the storm, the arrival might come with a mix as some marginal temps hang on- shown with the bold 540 thickness line on the GFS. The Canadian (white background), shows the Low a little farther east. Yesterday I mentioned the trend- and this trend east on the Canadian is better for us, but the cold air still gets pushed into PA. We can thank the the upper level flow around approaching Arctic air for that. This may act as a wave approaching shore, slightly warmer air gets pulled in before the crash of the cold. So while I disputed it a few days ago, the cold air doesn't really get in here until after this coast passes. In fact another short wave, or clipper will move through Saturday with our best shot of snow showers- leading the arctic charge.
This GFS 850mb plot is for Sunday morning. Here the temperatures at around 5000ft will be down to around -20C. That is -4F, and would translate to a struggle to reach the lower 20s on Sunday. If was have snow on the ground- it would likely keep daytime temps in the teens.

Updated: Record Anniversary Heat Wave and Elevation Snow

This is a quick morning update. I will do my best to post this afternoon with a snow-cast map.
First: This is the anniversary of the most impressive January Heat Wave on record in Baltimore.
The year: 1932

• January 13th: 76F
• January 14th: 79F * Hottest ever for the month
• January 15th: 78F

As for tonight's storm, still on the fence. My basic impression is two-fold.

1. As coastal develops, cold air will wrap in at cloud level, surface temps will be bordering freezing. That means sleet and snow likely, but higher elevations will have a better chance for 'stickage' and some accumulation. Note: BWI is near sea level. Towson, Cockeysville and Owings Mills are a little over 400Ft. Reisterstown and Parkton are close to 800Ft.
   
2. Monday morning the storm pulls away, but 'comma' head or heavy precip around the low center may clip eastern sections. Based on temperature profile and track, Cecil county could be the big winner. Early sampling shows potential for 3"-6" from Cecil County to Philadelphia. While NYC and Boston could get 1 foot of snow. Around the beltway, elevation plays role for north side to have the best shot of 'stickage' and accumulation... but roads temps may also be an issue.

Afternoon Update:
The storm might not look like much when you go to bed. It will develop overnight, but looks like just past us. Once a Low Pressure center passes our latitude (north of 39.0N) then we tend to get downsloped and cut off our precip. That looks like the position of the Low when it rapidly develops. The NAM model here for 7am Monday is actually the most impressive. Most have it well past us by then. If you watched the Packer's game last night and saw their snow- it's that Great Lake's storm that is pushing this coastal development a little farther east. This is the 3rd model run with with less moisture and warmer temperatures. I does not look promising! I've highlighted the general forecast area in yellow while the comma head I mentioned above just clips Cecil County. If you watch Good Morning MD on ABC2 I will be focusing on this Monday. Below is the video blog and my snowcast map.

This map was my call from home, below is Emily Gracey's map from ABC2. I think her conservative call on snow will work out better than mine... this made be just a little farther east, and pretty much done for us in the morning.

Saturday 2nd Post Afternoon:

No Snow= No Shave: Day 9
Will schools be delayed or closed on Monday??? I know it's already the buz, but still uncertain. Below I have detailed why, but just a call for snow in the forecast is not what students and teachers (even my new friends at Cockeysville MS) want. The return of winter is a guarantee, and if there has not been a reason to shave the beard by this time next week, I will be shocked.
My GFS Video Blog is at the bottom of this post showing a few changes I don't trust. As for the first event- Sunday night and Monday: The mid range models (48-60Hr) are now catching on to it. Rather than just show a map plot (you can still see the GFS in this morning's post), I wanted to show some of the extracted text I look at. Below you will see the AVN grid from Texas A&M for BWI. This break down can be overwhelming, so I just wanted to point out the important features. More below image:
First in universal time 00Z (Zulu or Greenwich Mean Time) is at night. and 12Z is morning. So 00Z Monday is actually 7pm Sunday evening, and 12Z is 7am Monday Morning.
While the surface temperature is expected to be 34F-35F, the 850mb temperature (~5000Ft) will be -2F to -4F. That includes the 1000-500mb thickness below 540, and further breakdown not on this output (1000-700mb and 700-500mb) justifies either sleet or a heavy wet snow- that might melt on roads.
It's a very tough call. The total precipitation is .54" liquid equivalent. That's enough if all snow to give 3-5 inches of heavy wet snow. If it was daylight, I would say just wet roads, and white grass. At night is a different story. It's been warm for a while, so the chances of the roads cooling down and beating the trucks will be tough. It was have to be at it's heaviest on Monday morning, which it might be- to get a delay. But further south, the lower your chances (B'more city and AA County). The trend of all models is for more on the E. Shore but warmer temps and into New England up to 1 ft. near Boston. I'll do my best for a snowcast tomorrow.

Video Blog of GFS 240Hr Model:

Pattern Change- Winter Will Return. SOON!

No Snow= No Shave: Day 8
I posted my reasons yesterday about the shifting pattern and return of cold to the east. The models are still dancing around the trough with a few shots of coastal storms. The GFS which I never liked, but has done the best job this year- has diminished Monday's coastal, but building up Thursday and a larger one Saturday. This video is my analysis of this model. Check it out and then fill out the poll to let me know if this is something I should try again.The problem is that this second storm keeps getting pushed back to day 6 or 7 on every run. It sees something, but how confident can we be in it this far out. I am also waiting for the 12Z run for the latest on next week. I may post again on that later today, but definitely over the weekend. For those of you that like analog year, January 2000 started off warm. Jan 2nd and 3rd were both 68F, the 4th was 70F.. then the pattern flipped. We were hit with 3 storms between the 20th and 30th resulting in a total of 23 inches. That was an above normal season for snow- most in just those 10 days. Just how it works out some times.
Great Pictures were emailed to me yesterday. I made a new slide show in the Album page- Best of Baltimore Jan2008. Check it out in addition to my Snow Page.

Warm Wet Weekend. Christmas Snow?

This morning's national radar seen here (3am to 5am) is a little bit of job security. No, I will never claim perfection-nor should any forecaster. Yet I did beat the computers on this one. Yesterday I mentioned the prospect of this southern storm being a little closer to us, and worth mentioning. This morning, while the surface low was chugging through GA and SC, the shield of rain was on our doorstep. While it was just patchy drizzle and flurries here, it helped to moisten up the atmosphere and set the stage for more today. Combine the east wind, and more drizzle and fog will form throughout the day, in fact into the weekend. Not 100% on my end, but I did mention the chance yesterday, while there was no support from NWS or the mid range models.

As for this weekend, I am sticking with the Canadian here, which show a chance of getting over 1 inch of rain. Here you can see the 500mb level (on the right) energy I marked with an X. That is the support for a second area of low pressure to form along the front to enhance the rain. That's a good soaker on a holiday weekend! The push of warm air will continue all day Sunday, so my forecast of 54F may actually occur at night.

CHRISTMAS SNOW?
Here again is the Canadian 500mb (roughly 18,000Ft) map. I've highlighted the troughs with an X to show the energy that will keep us active for the end of 2007. The one over Maryland is the support for flurries or light snow. It looked a little more yesterday on the surface prog maps, but there still is hope for the flakes. The system in New Mexico will reach us with rain or snow by next Friday. The Pacific NW trough will likely affect us after that, but the traditional La Nina pattern with storms riding the Great Lakes and giving us rain, is likely to continue for the next 2-3 weeks.

Split Decision

Today, a normal day for late December. This is essentially the shortest day of the year, well daylight for those who want to get technical. The Winter Solstice is over the weekend, but the change in daylight from today to Saturday is only a difference of 7 seconds. So today being the sunny one, enjoy it!
We have cold air (35F-40F) in here for tomorrow, but that will also push this current system to our south. That gives us the clouds, but no snow. The winds around the Canadian High Pressure will be from the northeast. That could add some moisture for an evening snow shower or freezing drizzle in spots..but it does not look like a big deal now. Not much model support, but I have been watching the radar all morning, showing a hint at the precipitation shifting a little farther north. It may be worth watching on our southern fringe.

The weekend storm, which is now in the Rockies, will take a track into the Great Lakes. There is our split. South and west, we keep missing our mark. That will certainly draw in warmer air and bring us plain old rain. Two questions arise, how much rain, and how warm. The GFS model I followed last week, is bringing a front in a weakened for Sunday Evening, while my trusty Canadian model is much more wet. For the purpose of impact, I am showing that Canadian here. An inch of rain would help our drought, and could be the cast, if this model verifies a wave of Low Pressure riding up the front. Behind that, I see an upper level disturbance with the cold air on Christmas day. This may provide some holiday flurries.

Day Off

I have today off, so if you notice some TV graphics on the web site have not been updated, that is why. You can continue to rate my forecast with the poll at the right. As of 10am, the average seems to fall in my own range of "low B". There is a hint that we may have another shot of snow or ice at the end of the week. I will dive into that tomorrow, and try even harder to hit it.

Falling Temps, Flying Leaves, and Flakes

Today: Blustery! What is the true definition of that? I usually consider it when the wind comes in bursts, surges, and makes it feel colder. Today would fit. As temperatures struggle the reach 40F, it will feel like the 20s. How about the snow as well. Following a few streamers from Lake Erie down into Dixie is tough. I did mention it on the air yesterday, but did not want to push it too much. Unfortunately enough did fall to coast the ground in northern Baltimore County and Carroll County. The roads were salted this morning due to icy spots. These flurries and snow showers will continue until mid day, but be isolated. You can ABC2's StormCenter Doppler in my Weather Graphics Page. But that isn't really the story today is it?
Tomorrow it will snow. For all of us. This is the model output for the NAM (North American Model), an upgrade from the former ETA, and has a tendency to overdue precipitation. I am using it, because the other images don't do a good job highlighting this clipper.
Two things to consider: First, when a clipper passes to our south, we often get the high end or more of snow. When it passes just north, we get much less or nothing. Second, there is cold air support for all snow. The general rule of thumb is 10 to 1. So multiply these numbers by 10 for an idea of snowfall.
From overnight the range of liquid equivalent forecasts for Baltimore are:
NAM:0.27"
GFS: .16"
*NGM:0.09" (but that only goes out until Wednesday at 7pm. I will update these numbers by noon)
My general call is for 1-2 inches of snow. The timing will be afternoon through midnight. That means the evening commute could be slippery as roads tend to accumulate snow when the sun gets low between 3pm and 4pm. It should end overnight, but if we get wet afternoon roads to ice up, then Thursday may warrant a school delay. December 5th recent snow history and video of my LIVE coverage from WBAL tomorrow.

I may be right, for the wrong reason...

A few days ago, I mentioned that we had a pattern shift and a chance that the weekend storm might bring snow or a mix. Here is the temperature map of the 850mb level (above 3,ooo ft) for Saturday. The wind flow is still NW, and our numbers are around -6C. This (cloud) level and number are important for wintry precipitation. The problem is that it will be clear early Saturday. But it does set the stage for the approaching storm.


The models have been all over the place - especially the GFS. Initially it had a Low passing to our west in the Great Lakes, Tuesday night it shifted the track closer to us due to the strong cold air mass and developing trough. Last night, it went back west. This time of year I would expect that track. Here is the same GFS model for Sunday morning. While the storm will be a mean wind and snowmaker for MN, it will push a wind shift to the south for us. As the cold air gets pushed out, the warmer air is forced up and over developing 'over running' clouds and wintry mix. The pink is that precip, while the yellow line shows the likely freezing line. However, that upper level temperature will be cold enough that the first round might be snow or sleet early Sunday. When the real 'stuff' gets here, it should be rain. This is the type of situation where temperatures warm overnight. As the storm passes, the colder air has a chance to bring some Lake Erie snow showers here on Tuesday. Still 4 days out, and the models may shift again....