WEATHER BLOG: 8:30 Update-Staying Consistent…It’s Scary
For the most part the forecast is still pretty solid. I’m beginning to think that this may be a more 1-2″ type thing for most areas with maybe an isolated 3″+ somewhere to the south of the metro, but the lower part of the atmosphere is pretty darn dry. Our surface dewpoints are still below 5° and the evening sounding shows some dry air in the lowest 5500 feet of the atmosphere which will take a bit of time to overcome. The lift though should be strong enough to take care of that layer pretty quick I hope. The models have reduced our QPF (total precip) to under 2/10″ so even at 12:1 ratios we’ll struggle to get over 2″ for the most part. So while the forecast will essentially stay the same I’ll be emphasizing the lower end of the range more than the upper end of the range. It still looks to me as if areas towards the S/SE of KC metro have a better chance of picking up a bit more. The timing hasn’t really changed too much, perhaps closer to 4AM though for the start time. Rush hour shouldn’t be impossible but it should be slick in areas and untreated roads will obviously fare worse than treated roads. Might be tough to actually plow this one and the chemicals should do a good job.
Temperatures haven’t really dropped much now that evening has settled in and with all the clouds in place, the only drop will be from the evaporating process of the snow falling and cooling the air down. So we may start tomorrow in the 26-29° range.
The end of the accumulating snow should be no later than 10AM so whatever you have then should about do it, and there will be some melting tomorrow PM.
I want to stress that this is not going to be a big snowstorm. As I’ve said for days it’s more of a nuisance thing, which if it held off till after rush hour would be a minor event int he scheme of things. The thing that makes this more dicey is the timing of the snow, coinciding with Monday’s AM rush. The PM rush should be a much smoother affair.
Have a good night and unless something changes the next update will be in the around daybreak on Monday.
As I start this blog with our “biggest” snow event on the way I believe for the winter season so far, and who knows, with the way the winter is going, this may be the biggest event of the entire season, I’m struck by how consistent the thinking has been regarding the upcoming snow heading towards the area. Also don’t forget to follow fox4wx on Twitter for updates throughout the day tomorrow, ranging from weather to traffic to anything else I think is important for you to know as the snow falls and ends.
We’ve been essentially saying the snow would be in the 1-3″ range for a couple of days now, the blog has been talking about this since last WED or last THU. What is unusual, and it makes me a little nervous, is that the modelling and the forecasts made off that data have wavered so little. What I’m trying to say is typically when a snow system is heading this way from 3-4 days out, you’ll often go through the ups and downs of forecasting the event. Depending on your perspective, if you love snow, sometimes the modelling will come out all of a sudden with very little, or if you really want the snow, you get excited when the modelling comes out and we get blasted with much more snow than what you were thinking. It typically is a series of ups and downs over the course of several days.
This event however, and granted Mother Nature has a tendency to throw some curve balls at us as the event unfolds, has been essentially a very predictable event to forecast for, at least so far. There hasn’t been much wiggling going on as you can read from previous blogs. Last night there was a definite uptick in the total liquid the “storm” was creating on the NAM model. This didn’t surprise me at all and I disregarded it because of the tendency for the model to over-predict moisture from 2 days out so far this winter. I wrote about that yesterday I think. Today the model corrected itself, and there is good agreement with the GFS in terms of us picking up essentially .2-.25″ of moisture out of this event. Converted to snow directly that would yield about 2-3″ of snow at KCI. The data is barely a bit higher for the south side towards Pleasant Hill, MO, with essentially a 2.5-3.5″ event there.
So what does this all mean? I’m not changing my forecast, nor will I touch it again till the late data comes out before and during the 9PM newscast tonight. Odds are the forecast will stay the same then too. Should it do that and should it play out as we all expect it too, this will be a very well forecasted storm for all involved I think. Now it’s just up to Mother Nature to not throw us any curve balls.
Another note for you, and we were heavily blogging about this about a month ago it seems, and this would be where this “event” would rank in terms of the latest 1″ 1st snows of the winter season. It’s VERY unusual for us to be waiting this long for our 1st 1″ of snow in a single “storm”. Yet here we wait. Here are the record latest dates for the 1st 1″ of snowfall.
4) 2/13/2012 (???)
The snow itself is blossoming nicely now through the Plains of Texas. Take a look at the surface map down there, I’ve circled the snow reports from the Noon hour, the ** represent snow falling. When you see 3 or 4 that represents moderate-heavy snowfall.
Meanwhile, now that our surface winds of switched to the S/SW, moisture is quickly streaming back into the Plains states closer to home. Take a look at the lunchtime satellite picture. You can clearly see the clouds that have rapidly developed and moved into the middle part of the country.
These clouds will quickly move in before sunset and take our virtually clear sky and turn it cloudy in a matter of an hour. They’re about 4-6K feet above the ground and are not very thick through the atmosphere. In and of themselves they won’t create snow, what that moisture will be waiting on is more lift in the atmosphere that will be moving in later tonight and through tomorrow AM, that will take that moisture in addition to the moisture associated with the storm itself and then we’ll get into the snow.
The timing of the snow I think is between 1-4AM for a start time, and then starting to wind down around 9AM in terms of the significant, accumulating snowfall. When the snow starts it should become moderate rather quickly and accumulate almost instantly. The pavement and all other surfaces will certainly be cold enough and there will be little to no melting, unlike some of the previous other “events” we’ve had so far this winter.
Temperatures for most of tomorrow AM should be in the 25-30° range and then we should be in the 30-35° range tomorrow afternoon. As the storm quickly incorporates drier air aloft, the snow should taper off fast during the mid morning hours. With the drier air aloft moving into the region, and all the moisture below that still lingering with some very weak lift in the lower part of the atmosphere, there will be, at times, some freezing drizzle and perhaps in the middle of the afternoon some liquid drizzle. The concern I would have about that is that we’ll need to watch for some refreezing tomorrow night, mainly on untreated road surfaces.
Tough to say if the kiddies get a snow day tomorrow. I’ve got no doubt there are some districts that will be ready to cancel school for a day, and it may be quite messy in the AM, but I’m told the kids have some days off later in the week so there might be a bit more of an effort to keep them in school for the day. It will be a marginal event in the big picture but it should be snowing pretty good between 5-7AM when all the decisions need to be made. That’s a tough call and one that I’m glad I won’t have to make.
So lets get to a few maps…again you’ll notice the strong similarities between the maps that I’m going to post and the ones that I posted yesterday, Again that get’s back to the consistency that’s been shown with the storm thus far.
First the NAM and then the GFS.
Click on those images to make them larger and more readable.
As I mentioned yesterday on the blog, there may be a sweet spot towards the south of KC of maybe a few pockets of closer to 4″+ snows. The area in question for that would be down towards Miami/Anderson/Linn counties, and Southern Bates/Henry/St Clair and maybe Johnson and Pettis counties on the MO side.
I’ll put together another update for you tonight around 9PM or so on the weather blog. Thanks for reading!