Jump to content
  • Member Statistics

    17,606
    Total Members
    7,904
    Most Online
    ArlyDude
    Newest Member
    ArlyDude
    Joined

September 2012 General Discussion


Brewers

Recommended Posts

Saturday morning looks to be interesting in southern WI! Or could be at least.

Temperature dropping quick this evening here. Already 46°, with a 40° dewpoint.

Yeah, maybe a dusting... though snow melting on contact is more likely if it actually did snow, and it could end up just being rain given the warm sfc temps. I'm leaning towards rain given the current forecast but a small change could make the difference.

Link to comment
Share on other sites

  • Replies 986
  • Created
  • Last Reply

Yeah, maybe a dusting... though snow melting on contact is more likely if it actually did snow, and it could end up just being rain given the warm sfc temps. I'm leaning towards rain given the current forecast but a small change could make the difference.

Eh, there's a shot in W Wisconsin and NW Illinois in the freezing/subfreezing temp zone on the GFS, but the NAM is less than enthusiastic about the system as a whole, not giving anyone east of Madison any precip at all, and only light amounts in W Wisconsin.

Link to comment
Share on other sites

Eh, there's a shot in W Wisconsin and NW Illinois in the freezing/subfreezing temp zone on the GFS, but the NAM is less than enthusiastic about the system as a whole, not giving anyone east of Madison any precip at all, and only light amounts in W Wisconsin.

Considering the origin of the potential system it is not a surprise the NAM is struggling with it.

Link to comment
Share on other sites

Sun is rising and revealing the gloominess of today, solid band of precip off to the west associated with low level warm air advection and the associated frontogenesis. Fairly cold air on our side of the front, 850s between 4-5 °C. The WAA isn't expected to get to Madison, rather 850s will cool slowly throughout the day from weak CAA as some precip from the warm upglide makes its way in.

Eh, there's a shot in W Wisconsin and NW Illinois in the freezing/subfreezing temp zone on the GFS, but the NAM is less than enthusiastic about the system as a whole, not giving anyone east of Madison any precip at all, and only light amounts in W Wisconsin.

My guess is if some decent bands/showers set up with moderate rates we'll see snowfall reports from dynamical cooling, boundary layer temps are too warm for light precip to make it to the ground frozen. Pretty common this time of year to have cold enough 850s with too warm of a boundary layer.

Link to comment
Share on other sites

MESOSCALE DISCUSSION 1978

NWS STORM PREDICTION CENTER NORMAN OK

0136 PM CDT FRI SEP 21 2012

AREAS AFFECTED...CNTRL IL...WCNTRL IND

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 211836Z - 212000Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...AN ISOLATED SEVERE THREAT IS EXPECTED TO DEVELOP ACROSS

CNTRL IL INTO WRN IND THIS AFTERNOON. ISOLATED LARGE HAIL AND WIND

DAMAGE WILL INITIALLY BE THE MAIN THREAT. AN ISOLATED TORNADO THREAT

COULD ALSO DEVELOP LATER THIS AFTERNOON. WW ISSUANCE MAY BECOME

NECESSARY ACROSS THE REGION ONCE THE SCENARIO BEGINS TO UNFOLD.

DISCUSSION...THUNDERSTORMS ARE CURRENTLY INITIATING AND INCREASING

IN INTENSITY JUST TO THE EAST OF A DEEPENING SFC LOW CENTERED OVER

NE MO. THE STORMS ARE LOCATED ON THE NERN EDGE OF INSTABILITY AND ON

THE NOSE OF A MID-LEVEL JET MOVING INTO THE REGION FROM THE WEST

NORTHWEST. THE STRONG MID-LEVEL FLOW ASSOCIATED WITH THE JET IS

CREATING FAVORABLE SHEAR PROFILES FOR SEVERE STORMS IN SPITE OF THE

WEAK INSTABILITY IN PLACE. THE WSR-88D VWP AT SPRINGFIELD IL

CURRENTLY SHOWS ABOUT 65 KT OF 0-6 KM SHEAR WITH SUBSTANTIAL VEERING

WITH HEIGHT FROM 2 TO 3 KM. THIS COULD SUPPORT A SUPERCELL THREAT AS

LOW-LEVEL MOISTURE ADVECTS NWD INTO THE MCD AREA AND INSTABILITY

INCREASES. 500 MB TEMPS OF -15 C TO -19C WILL BE SUPPORTIVE OF

ISOLATED LARGE HAIL WITH THE MORE INTENSE CORES. IN

ADDITION...LOW-LEVEL LAPSE RATES HAVE STEEPENED SOME ACROSS ECNTRL

IL INTO WRN IND AS SHOWN ON MESOSANALYSIS WITH 0-3 KM LAPSE RATES

NOW AROUND 7.0 C/KM. THIS ALONG WITH THE STRONG WIND FIELDS AT

LOW-LEVELS MAY SUPPORT AN ISOLATED WIND DAMAGE AS CELLS MATURE LATE

THIS AFTERNOON. AN ISOLATED TORNADO THREAT COULD ALSO DEVELOP

ESPECIALLY IF THE CELLS CAN ROTATE AND PERSIST.

Link to comment
Share on other sites

Had to turn on the heat a little while ago! :shiver: High of only 56° today - big forecast bust on temperature. 0.38" of rain so far. Temperature is really going to drop if it clears out. Only 50° right now.

What the NAM is showing for precipitation type tomorrow morning!

cld18.gif

Link to comment
Share on other sites

66º for the high and 0.41" of rainfall at LAF today.

0.66" through 8:00pm at IND, which puts them at 6.06" for the month...good for the 11th wettest September on record (since 1871). Still more to go down there tonight.

10.37" in 2003

9.33" in 1926

8.17" in 1896

8.06" in 1989

7.61" in 1996

7.54" in 1921

7.46" in 1895

7.31" in 1890

7.18" in 1932

6.94" in 1879

6.06" in 2012

Link to comment
Share on other sites

It's in the 30s already in Rhinelander, Tomahawk, and Eagle River under predominantly clear skies. A band of precipitation associated with the disturbance is approaching NW Wisconsin as we speak. I'm not sure it will make it that far east, but if it does, it will be interesting to watch the temperature and precipitation trends.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...