[MCD] SWOMCD

[MCD at goshenarc.org]

ACUS11 KWNS 071828
SWOMCD
SPC MCD 071827 
ILZ000-MOZ000-072330-

MESOSCALE DISCUSSION 0042
NWS STORM PREDICTION CENTER NORMAN OK
1227 PM CST FRI JAN 07 2005

AREAS AFFECTED...SWRN/CNTRL/ERN MO...WRN IL

CONCERNING...HEAVY SNOW 

VALID 071827Z - 072330Z

MODERATE SNOW COULD DEVELOP OVER PARTS OF MO BY LATE AFTERNOON.
SNOWFALL AMOUNTS WILL INITIALLY BE LIMITED BY WARMING SURFACE
TEMPERATURES AND RELATIVELY DRY AIR THROUGH THE LOWER TROPOSPHERE.
HOWEVER...THESE LIMITATIONS ARE EXPECTED TO BE OVERCOME BEFORE EARLY
EVENING TO SUPPORT A BAND OF ACCUMULATING SNOW...PERHAPS MIXED WITH
A LITTLE SLEET...FROM CNTRL MO INTO WRN IL.

A FAST MOVING UPPER AIR DISTURBANCE WILL DEVELOP NEWD FROM TX/OK AND
ACROSS MO THROUGH 08/00Z. STRONG DYNAMIC FORCING AND MOISTENING WILL
ACCOMPANY THIS DISTURBANCE AND SHOULD OVERCOME INITIAL LIMITATIONS
MENTIONED ABOVE. 12Z ETA/RUC...AND LATEST 15Z RUC...SUPPORT THE
DEVELOPMENT OF A RELATIVELY QUICK BURST OF MODERATE SNOW DURING THE
LATE AFTERNOON IN A SW-TO-NE CORRIDOR ACROSS MO. BY
EVENING...SNOWFALL POTENTIAL IS EXPECTED TO INCREASE INTO PARTS OF
IL.

LATEST SATELLITE AND RADAR TRENDS LEND SUPPORT TO THE ETA/RUC FCSTS
WITH CLOUD TOP COOLING INDICATED WITHIN INCREASINGLY WELL-DEFINED
MID LEVEL BAROCLINIC LEAF FROM ERN OK INTO WRN MO. CLEAR-AIR MODE
RADAR RETURNS ARE ALSO EXPANDING/INCREASING ALONG THE SERN EDGE OF
THE BAROCLINIC LEAF WHERE MID LEVEL ASCENT IS LIKELY STRENGTHENING.
ADDITIONALLY...VORT MAX/IPV INTRUSION APPEARS TO BE INTENSIFYING
WITH PRONOUNCED DARKENING NOTED ON WV IMAGERY OVER NWRN TX.

AS THIS STRENGTHENING IMPULSE LIFTS RAPIDLY NEWD ACROSS MO THROUGH
LATE TODAY...STRONG ASCENT AND ADIABATIC COOLING WILL ACT ON
ELEVATED GULF COAST MOISTURE RETURN TO RESULT IN THE DEVELOPMENT OF
A NARROW AXIS OF MODERATE SNOW. RAPID MOVEMENT OF THE UPPER SYSTEM
SUGGESTS THAT DURATION OF HEAVIEST SNOWFALL ACROSS MUCH OF MO SHOULD
BE SHORT. HOWEVER...CONDITIONS MAY BECOME INCREASINGLY FAVORABLE FOR
MODERATE TO HEAVY SNOW FROM ERN MO...ACROSS THE MS RIVER INTO IL
BEYOND 08/00Z.

..CARBIN.. 01/07/2005

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

...NOTICE...
SPC WINTER WEATHER MESOSCALE DISCUSSIONS WILL BE ISSUED ON A 
SCHEDULED BASIS...FOUR TIMES A DAY...BETWEEN 00-01 UTC...
06-07 UTC...12-13 UTC...AND 18-19 UTC AS SIGNIFICANT SHORT
RANGE WINTER WEATHER EVENTS UNFOLD.  THIS SCHEDULE WILL BE
USED FROM DECEMBER 1 THROUGH FEBRUARY 28.

ATTN...WFO...LSX...SGF...EAX...

38009146 37719224 37509298 37119380 37139440 37599452
37909424 38169382 38379337 38919260 39379174 39619093
39279025 38599026 38289076