Monday, February 9, 2004


MON 2/9 EVENING UPDATE:
"LET'S GET READY TO RRRRUUUUUMMMMBBBBLLLLE!"


That means just what it says:
- The Baltimore metro area will experience one of the longest stretches of less than 5 days of school in recent memory... Jan 12 was the start of the last full week of school... and the mayhem will not end until Monday March 8 or later.

- The next two weeks will feature a rapid return to winter, with 2... COUNT EM, 2 SNOWSTORMS for the Mid-Atlantic States. Yes, that includes Philly and Baltimore. Oh I can hear the powderhounds howling now. This is not wish-casting, this is not hype-casting, this is the real McCoy.

For those who want to think winter is over and it is time to start spring cleaning… please, by all means, begin now. We will never squelch hope and inspiration on this site. But for those who have decided on the sobering reality that is it barely the middle of February, you are better off accepting (or at least trying to believe) that the worst of winter may have not yet arrived.

Let’s deal with a few questions that many of you have first:

1. WILL WE GET ANOTHER BLIZZARD LIKE LAST YEAR? The answer is probably not. The reason is simple. The big storms of the 2002-03 winter were strongly influenced by El Nino off the west Mexican coast, among other factors. El Nino is the term used to describe what happens when the temperatures of the Eastern Pacific are warmer than normal over a several month period. What ends up happening in an El Nino year, if the right conditions are in place at the right time, is that the warm waters can more readily evaporate moisture. If the southern jet stream is active, meaning that it is moving quickly across Mexico and the Gulf Coast, it can rapidly move that moisture into regions which are favorable for storm development… the southern plains and Mississippi valley. The last piece of the puzzle is an arctic high pressure sinking southeastward from Canada… but not moving too fast. If a strong low pressure forms in the Gulf, brings that Pacific moisture with it, and rides the jet right into the arctic high…BANG you have a blizzard. Well, this winter, temperatures of east Pacific waters have been generally where they should be…not too hot and not too cold. Although the southern stream has been very active for 2 weeks or so, it does not have the high moisture content we saw in 2003. So the likelihood of another great big mongo 2-3 foot snowstorm is very, very slim.

2. SO WHY ALL THE ICE STORMS THIS YEAR? Once again, blame El Nino. I’m not sure I fully understand this part myself, but something weird happens in non-El Nino years. The lack of warm water off the Pacific coast somehow influences the movement of the southern jet stream. It is not as constant, and fluctuates from week to week, as we have seen this year. The result? Instead of every storm moving across the country delivering plain old snow to the northeast, (like in 2003) the southern stream will occasionally “cut up” through the Ohio Valley, so the storms we get are more ice and rain than snow. It would seem weird that a LACK of warm water in the Pacific would somehow turn into WARMER storms for the I-95 corridor. But that is one of those variables of the atmosphere. Figure that one out and you could run your own weather business.

3. SHOULD I RUN OUT AND STOCK UP ON BREAD, MILK AND SALT NOW? I think you can hold off with the bread and milk. Salt, you should definitely reload on that. And while you're at the store, pick up some chips and salsa so you have something to munch on the next few days while you curl up by the fire and read Foot's Forecast.

4. WHAT IS IT YOU ARE SAYING THEN? It takes a while for the atmosphere to finally get it’s act together and come up with a discernable pattern we Earthlings can detect and understand. You know us humans, always looking for a pattern. In November it was the “way warm” pattern, in early December it was the “early winter” pattern, followed by the late December “what winter?” pattern. January delivered what I call the “From Russia With Love” pattern as we saw classic cross-polar flow, better known as the Siberian Express. The last ice storm was basically the dying breath of that pattern, and now this little calm and partly cloudy interlude is simply the atmosphere reorganizing and RELOADING for it’s final extravaganza. This is the stuff that dreams are made of, as once the southern stream, the northern stream and an arctic high get into the act….well this is why some of us love storms so much. And this is why I personally love THIS time of year on par with sunny May, sultry July and glorious October. The next three weeks are guaranteed to be a full-fledged live concert event featuring all your favorite players from the entire winter wrapped into one big 3 week long mega, multi-storm pattern I can only call…

FABULOUS FEBRUARY

So here we go kids, put your seatbelt on and close your visor, cause as old Doc Brown would say “where we’re going, we don’t need roads.” And come next week, you’ll see what I mean.

Storm # 1 – The stage is being set later this week and this weekend for a significant snow event to take shape in the middle of next week, either a Tue-Wed deal or a Wed-Thu deal which if it is enough would deliver a knock-out punch to the end of the week and turn Wednesday into a Happy Friday (especially for 12th graders… who could care less about how many snow days we get, they don’t have to make them up!). The synopsis is that you will see temperatures trend downward later in the week, and get quite cold this weekend as another arctic high begins settling into the region. But wait! There’s more…. This is NOT your father’s arctic high. When I look at the computer model projections… the setup for next Monday is sneakingly similar to the setup for the blizzard, minus the big time moisture as we talked about above. So the high basically parks over New England and is one of those extenders. It extends all the way back to the central Canadian provinces. That means this high will have a fresh supply of cold air being redelivered… mmmm…right into the hands of a low pressure coming out of the Gulf, being charged up by… you guessed it...southern jet stream laded with moisture. The northern jet stream is meanwhile being tightened by the fact that it can’t go OVER the high, it can’t go THROUGH the high, so it has to squeeze UNDER the high… oooh, look, right into the hands of the southern jet stream which is sending on up to the Mid-Atlantic a….. BIG LOW PRESSURE.

So the point with Storm # 1, it is a classic southern storm caused by the tightening of the two jet streams, one delivering the cold air, the other delivering the moisture. The key element is the tightening has been projected to occur over the Mid-Atlantic.

How much snow and when? Early indications based on what is called QPF (Quantitative Precipitation Forecasts) are roughly .75 to 1.25 inches of liquid for the Baltimore-Philly area. So you do the math… 1 inch of rain is 10 inches of snow at 30 F, which is a 1:10 ratio. But if it is 20 F at the surface, the ratio becomes 1:20. The computer models are going to go through several incarnations of this storm for at least 3-4 more days before the weather service will begin paying serious attention to it. If the models remain gung-ho by Thursday, then by Friday the weather service will issue a Special Weather Statement saying ‘WINTER STORM POSSIBLE TUESDAY INTO WEDNESDAY.”

Storm # 2 - Will be similar to #1 but will feature a more westerly component, but that is well over 10 days away, so can't be too sure of it. Especially considering that computer models may not be incorporating a much denser and more southerly coverage of snowpack by then, which tends to change the ultimate output of their projections. Time frame is still a Feb 24-25 period.

I can be sure of one thing, only God and his weather department are the ones who truly know what will happen. But for now, we’ll take advanced computer modeling as our little piece of divine inspiration for those looking to have a big snowy grand finale to this winter.

Hence the title for this post....


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