The prep (forecasting) is over. The fearless forecasters of Mpls/St. Paul are now taking their tests as the snowstorm is well underway. Check back Tuesday morning to see what grades they receive on their latest effort.
Check back late tonight to see how forecasters are progressing on their forecasts for Thursday. Follow us on Twitter for occasional updates.
NWS MPX was probably right with their discussion this morning. They suspected that it might not reach warning criteria.
ReplyDeleteMODELS ALL
CONSISTENT WITH WIDE SWATH OF AROUND 0.5 INCH QPF THROUGH
TONIGHT...AND WITH SNOW RATIOS RANGING FROM 10:1 TO 14:1...THIS
SUPPORTED SNOWFALL TOTALS OF 5 TO 7 INCHES ACROSS THE WARNING AREA.
WITH 200 MB WAA RANGING FROM 10 TO 16 DEG C/12 HR...THE COOK METHOD
WOULD SUPPORT SNOW TOTALS SUCH AS THIS. LOOKING AT THE GARCIA
METHOD...THE SPEC HUMIDITY ON THE ISENTROPIC SFC OF CHOICE /295 K/
IS EXPECTED TO BE AROUND 3 G/KG...WHICH AGAIN SUPPORTS THE IDEA OF 5
TO 7 INCHES ACROSS THE WARNED AREA. THIS WOULD MAKE CURRENT SNOWFALL
PROJECTIONS A BORDERLINE WARNING AT BEST...WITH LOCATIONS EAST OF A
LINE FROM BELLE PLAINE TO MILLE LACS LAKE CURRENTLY FORECAST TO FALL
SHORT OF 6 INCHES. TOSSED AROUND THE IDEA OF TRIMMING SOME OF THESE
COUNTIES OUT OF THE WARNING...BUT DID NOT LIKE THE IDEA OF REMOVING
COUNTIES BEFORE THE FLAKES EVEN BEGIN TO FLY. PLUS...FROM THE IMPACT
PERSPECTIVE...THIS ONE SHOULD BE RATHER HIGH...AS ALTHOUGH WE ARE
ONLY EXPECTING 5 TO 7 INCHES...THAT SHOULD ALL FALL IN A 4 TO 6 HOUR
WINDOW. WITH RATES OVER 1 INCH PER HOUR...
Agreed. I bet the airport doesn't go over 5 inches.
ReplyDeleteLooks like the 12z NAM run was right with the most snow being over SC Minnesota. Most sources had the most snow north of the cities.
ReplyDeletehttp://www.twisterdata.com/data/models/nam/221/maps/2010/12/20/12/NAM_221_2010122012_F24_PCPIN_24_HR.png
4.4" in St. Paul
5.2 in Chanhassen.