Monday, January 26, 2009

Snow Storm Update

So far, this storm has been anything but impressive in Mid-Missouri. This is where I wish I had a meteorology degree, so I could figure out just what is happening. My best guess is that one of two scenarios are occurring: Either the track of the low has taken a more southerly turn, or drier air has advected into our region. Whatever the cause, the effect is the same.

It has been cold and cloudy all day. Some light frz rain/sleet began to fall at 4:30 p.m. and lasted for about 45 minutes, leaving another dusting on the ground. Nothing has happened since...here at least. Looking further south paints a much different picture.



Much of my family is in the Rolla/Steelville area, and they are getting battered with moderate to heavy sleet at this time. My sister in Steelville reported to me that she has an estimated 1/2" of sleet on the ground currently. With the forecast of a couple more hours of sleet and ice, followed by some heavy snow, it's possible that they might end up with quite a mess tomorrow morning. Schools there have already been cancelled. (I'm still holding out hope for me, I need some time to grade some tests)

I am beginning to notice what may end up being a characteristic to remember about this storm. The general NE flow of the precip is setting up the stage for some very steep snowfall amount gradients.

From the St. Louis NWS discussion: THE MOST UNCERTAINTY DEALS WITH HOW FAR NORTH TO TAKE THE MODERATE TO HEAVY ACCUMULATIONS OF SLEET AND SNOW. THIS COULD VERY WELL BE THE SITUATION WHERE THE NORTHERN PART OF THE ST. LOUIS METRO AREA ONLY RECEIVES A COUPLE INCHES OF SNOW...BUT JEFFERSON AND MONROE COUNTIES RECEIVE 6+ INCHES OF SNOW AND SLEET. THIS DEMARCATION LINE COULD END UP BEING A COUPLE OF COUNTIES NORTH OR SOUTH OF CURRENT FORECAST.

This reminds me of a wild snow event that occured in Southwest to East Missouri in March of 2008, where the difference of 20 miles meant the difference of 10" of snow in places. Check out the storm summary:

In East Missouri:



In Southwest Missouri:



Follwing the strip from bottom left to top right (Cassville to Jefferson City) was an area of 4"-8" of snow, while the adjacent areas had <1".

Tonight, some areas in SE Missouri are under the gun to receive up to and exceeding 1" of ice. I certainly hope that doesn't pan out for them, as I know how crippling that could be for many.

6 comments:

Josh Herman said...

I logged on in hopes of a report and I got one! A Great one at that. Looks like STL is getting a good dose right now and Fulton is dry. It's just missing you to the south... how disappointing! Looks like the snow is moving directly up 44 in the Rolla area. I am sure that hwy is a mess tonight.

I need to dig in my crates of radar loops and find the US loop for March 4, 2008. (this is acting as a reminder for me) We'll compare this one with that one after it's all said and done.

WxWatcher said...

I would like to see that radar loop for sure!

Update as of 3:30 a.m.:
It seems that we didn't get any more snow last night until just about an hour ago, when a small band of moderate snow formed and dumped approx. 1 inch. I think my report may show right at an inch this morning.

Josh Herman said...

At least you have an inch to measure! All we have up here is the rate of sublimation. :)

Josh Herman said...

I found the radar images and looped them from Mar 3-4, 2008 (link below). Interesting system. A bit different looking from the system currently creating havoc. Looking back at my data for those days... we got quite a bit of rain. Colder air finally arrived and graced us with some snow.

My numbers for Mar 3-4:
Max..... 41.2° (Mar 3)
Min..... 10.2° (Mar 4)
Snow.... 2.2"
Precip.. 0.54"
Depth... 10"

US radar loop - Mar 3-4, 2008 (5MB)

Josh Herman said...

Regarding that swath of snow though, you can really see it setting up and snowing heavily for a long period of time. I am glad you referenced this date... it's been a blast analyzing it.

Daily Weather Map - Mar 4, 2008

WxWatcher said...

I did a quick check of this station's March 3, 2008 Report.

Looks like we had quite a bit more moisture with that system (makes sense with the higher amounts and time of year). We reached 70° the day before.

Thanks for posting the radar loop and daily weather data! I wasn't aware of the "Daily Weather Map" page on NOAA's website. That's a great resource for my classroom.

On the radar loop, it sure is easy to see the band of snow develop and "sit" right on top of the area from southwest to central MO! Just another reason why forecasting snow amounts can be so tricky. I've got tons of respect for the people in that position.