Updraft: February 28, 2011 Archive

3rd snowiest winter likely; Thaw in sight?

Posted at 7:40 AM on February 28, 2011 by Paul Huttner (2 Comments)
Filed under: Winter/spring 2011

The numbers are looking "good" for the 3rd snowiest winter on record in the Twin Cities, and it looks like we'll at least make a run at #1.

Here are the totals so far in the "Mega Winter" of 2010-'11:

76.5" season snowfall total so far at MSP Airport.
(Currently the 9th snowiest winter on record for MSP)

13.5" average snowfall for March & April

90" Where MSP season snowfall total would end up with just average snowfall

98.6" The snowiest winter on record in 1982-'83. (Another 22.1")

A look at the medium range maps this week yields 3 more chances for snowfall in the next 10 days.

Wednesday night & Thursday: A shot of lighter snow
(1" to 3" range?) for the metro & southern Minnesota, could be heavier up north.

Sunday: Another shot of snow possible.

Next Tuesday March 8th: Maps advertising potential for a major winter storm.

Models advertising potential (lighter) snow events Thursday & Sunday.(Click to enlarge)

GFS hints at possible major storm March 8th.

It is possible MSP (and much of Minnesota) could pick up our remaining average snowfall of 13.5" in the next 10 days!

Based on that notion, I'd asses the following probabilities for reaching season snowfall thresholds by mid April.

5th snowiest winter on record (84.1") 90%

3rd snowiest winter on record (88.9") 80%

1st Place: Snowiest winter on record (98.6") 50% (a 50/50 shot)

Average high now above freezing!

Want some brighter news? At least our average daily high temperature is now above freezing in the metro. The average high at MSP this week is 33 Monday, and rises to 35 degrees by Saturday!

The average high is 40 by March 16th, and hits 49 by the last day of March! It gets tougher to keep much snowfall around with the higher sun angle in a month. If you're looking for some trends of spring, hang in there about 2-3 weeks!

Evening daylight:

Sunset in the Twin Cities is now at 6pm this week. The sunset will remain at 6pm or later from now until November 2nd! Look for a noticeable increase in daylight well into the evening the next few weeks. Here's a great site to check out sunrise & sunset times for any location.

Twin Cities daylight in March
(Click to enlarge)

Push-pull weather pattern:

The "polar front" jet stream is right overhead this week. That means a fast moving series of fronts will pull milder air ahead of passing low pressure systems, then push colder (remnant arctic) air down behind. Look for alternating milder and colder days for much of this week. Right now Tuesday and Thursday look like the milder days, with highs in the 30s.

Meteorolocial Spring begins Tuesday!

For record keeping purposes, we can kiss meteorological winter goodbye today. The coldest 3 months of the year historically are Dec-Feb. March-May marks meteorological spring.

It won't feel like spring right away this year as it did last year, but there are signs that some milder air is beginning to push this way, At least we'll hit the 30s this week! Last year it was like somebody flipped the "instant spring" switch around March 1st.

The weather maps and overall pattern suggest it will really look and feel like winter for at least another 10-12 days.

Bigger thaw in sight?

The latest GFS runs are hinting at a change in the upper air pattern that could produce a bigger thaw the weekend of March 12 & 13th. It's too early to bank on it yet, but if the pattern pans out temps could soar into the upper 30s or even 40s by that weekend.

Major flood risk remains:

While spring lovers might revel in warmer temps down the road, they will also be the initial trigger for snowmelt and rapid river rises. There is still a good 4" to 6"+ of water locked up in snowpack in the Minnesota and Red River basins.

There is more than 10" locked up in snowpack near the BWCAW and the North Shore! After years of drought, it looks like North Shore Rivers will be raging this spring and early summer.

(Click to enlarge)

For hydrologists it's all about "Snow Water Equivalent" or "SWE"...that's the measure of how much water content is in the snowpack outside your window. SWE is a much better tool than snow depth at calculating eventual river rises. Hydrologists will be watching to see how much additional SWE id "deposited" between now and flood time this spring.

With 4" to 6"+ SWE on the ground already, this still looks like a major to epic spring flood season any way you slice it.

PH

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