FXUS63 KDVN 082139
AFDDVN
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
339 PM CST TUE DEC 8 2009
.SYNOPSIS...
THE WINTER STORM CONTINUES TO DEVELOP OVER THE TX PANHANDLE AND
WRN OK. AT 20Z A SURFACE LOW WAS LOCATED OVER THE TX PANHANDLE
WITH IMPRESSIVE 3HR PRES FALLS AROUND 6MB JUST EAST OF THE LOW AND
AROUND 9MB FUTHER NE IN NE MO AND WCNTRL IL. LIGHT TO MODERATE
SNOW HAS BEEN OCCURRING OVER MOST OF THE AREA SO FAR TODAY. THIS
AFTERNOON WARM PUSHING N AHEAD OF THE STORM HAD CHANGED THE SN TO
A MIX OF SN/PL/FZRA/RA OVER THE FAR SOUTH. THE MORNING H8 ANALYSIS
CONTINUED TO SHOW STRONG BAROCLINICITY AHEAD OF THE SYSTEM OVER
THE SRN PLAINS THROUGH THE MID MS VALLEY. GULF MOISTURE WAS
STREAMING NORTH WITH H8 DEWPOINTS OF 8 TO 10C AS FAR N AS ERN OK
AND NRN AR AS OF 12Z.
&&
.SHORT TERM...
ALL HEADLINES WILL REMAIN IN PLACE WITH THE EXCEPTION OF THE
BLIZZARD WATCH WHICH WAS UPGRADED TO A BLIZZARD WARNING.
THE WINTER STORM STILL LOOKS ON TRACK AND STILL LOOKS VERY
DANGEROUS FOR MUCH OF THE AREA. THE 12Z RUNS OF THE
NAM/GFS/UKMET/ECMWF WERE ALL CLOSE ON THE PATH AND TIMING OF
SURFACE LOW AS IT LIFTS NE THROUGH MO THIS EVENING AND INTO SRN LM
BY WEDNESDAY MORNING. HEAVY SNOWS ARE STILL EXPECTED TO
OVERSPREAD THE AREA THIS EVENING WITH A FZRA/PL MIX IN THE
SOUTHEAST. THE SNOW WILL CONTINUE INTO WEDNESDAY. HIGHS WINDS
AROUND 35 MPH WITH GUSTS AT OR NEAR 50 MPH LATE TONIGHT AND
WEDNESDAY ARE STILL EXPECTED AND WILL CAUSE CONSIDERABLE BLOWING
AND DRIFTING SNOW ESPECIALLY OVER THE NW HALF OF THE CWFA.
AS FAR AS SNOWFALL AMOUNTS GO THE MIX OVER THE SE THIS AFTERNOON
AND THIS EVENING WILL CUT INTO SNOWFALL TOTALS AND HAVE ADJUSTED
DOWN SOME. HOWEVER AMOUNTS WERE KEPT CLOSE TO 6 INCHES IN
ANTICIPATION OF SOME THUNDER SNOW THIS EVENING. OVER THE REST OF
THE AREA AMOUNTS APPROACHING A FOOT ARE STILL POSSIBLE BY
WEDNESDAY AFTERNOON. ...DLF...
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY...
WED NIGHT...WILL MAINTAIN BLIZZARD WARNING GENERALLY ALONG AND
NORTH OF HWY 30 FOR CONTINUING SEVERELY REDUCED VSBYS DUE TO
BLOWING SNOW THROUGH 06Z BUT CHANCES ARE THAT IT WILL BE ABLE TO
BE TRANSITIONED EARLIER INTO A WINTER WEATHER ADVISORY FOR BLOWING
SNOW AND EVENTUALLY WIND CHILLS NEAR OR REACHING ADVISORY
CRITERIA. WIND CHILL ADVISORY GENERALLY REACHED AFTER 08Z THU
ALONG AND NORTH OF I80. MODELS IN GOOD AGREEMENT OF INCREDIBLE
H972-H975 MB SFC LOW PROGRESSING NORTHEASTWARD ACRS LK HURON
AROUND 00Z THU. SFC PRESSURE GRADIENT FINALLY TO RELAX LOCALLY
AFTER 08Z THU.
THURSDAY...BRUNT OF LLVL COLD POOL TO SEEP OFF TO THE NORTHEAST ON
THU BUT SFC TEMPS STILL WILL STRUGGLE TO RECOVER INTO THE LOW TO MID
TEENS. SFC WINDS OF 10 TO 20 STILL WILL MAKE FOR SUB-ZERO WIND
CHILLS. A COLD NIGHT THU NIGHT WITH ANY CLEAR SKIES AND SFC WIND
DECOUPLE SOME VALUES WILL BE WELL BELOW ZERO AND COLDER THAN WED
NIGHT OVER FRESH SNOW COVER.
FRI NIGHT...THE NEW EURO IS NOT AS BULLISH IN BREAKING OUT LIGHT
ELEVATED WAA TYPE SNOW BUT WILL STILL KEEP SLIGHT CHC ACRS THE SOUTH
AND AWAIT ANOTHER RUN FRO CONSISTENCY. IF LLVL STRATUS CAN FORM
WHILE MID LEVELS STAY DRY...THERE MAY BE MORE OF A FREEZING DRIZZLE
THREAT LATER FRI NIGHT AND INTO SAT.
SUNDAY INTO MON...THE GFS...CANADIAN AND 12Z RUN ECMWF ALL ARE
VARYING IN TRYING TO PHASE A DISTURBANCE IN SPLIT FLOW REGIME AND
FROM AN INVERTED TROF COMPLEX AT THE SFC WHICH COULD BE A SNOW MAKER
FOR THE LOCAL AREA SOME TIME SUNDAY INTO MONDAY. FOR NOW WILL JUST
KEEP SLIGHT CHC POPS SUNDAY NIGHT INTO MONDAY...WITH THE POSSIBILITY
OF THIS SYSTEM PRODUCING ACCUMULATIONS OF ADVISORY CRITERIA
SOMEWHERE IN OR NEAR THE DVN CWA.
LONGER RANGE SIGNALS INTO NEXT WEEK/TUE INTO WED/...MEDIUM RANGE
ENSEMBLES SUGGEST THE UPPER MIDWEST TO GET A REINFORCING COLD DUMP
IN NORTHERN STREAM TROFFINESS...WHILE THE ACTIVE SOUTHERN STREAM
SHUTTLES ANOTHER MAJOR SYSTEM WELL TO THE SOUTH OF THE AREA ACRS
THE LOWER MS RVR VALLEY AND GULF STATES. ..12..
&&
.AVIATION...
WIDESPREAD IFR/LIFR EXPECTED THROUGH 18Z WEDNESDAY. A MIX OF
FZRA/PL/SN WILL OCCUR A KBRL AND KMLI INTO TUESDAY EVENING THEN
CHANGE BACK TO SN/+SN. KCID/KBQ WILL SEE PDS OF SN/SN+ THROUGH THE
EVENING. AFTER 06Z WINDS TO TURN NW AND INCREASE TO 25-30KTS WITH
GUSTS TO 35-45KTS CONTINUING THROUGH WEDNESDAY MORNING. THIS WILL
CAUSE NEAR ZERO VSBSYS IN SN/BLSN AT ALL TAF SITES. ...DLF...
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR BENTON-
BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA-
IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA-
MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT CST WEDNESDAY
NIGHT FOR BENTON-BUCHANAN-CLINTON-DELAWARE-DUBUQUE-JACKSON-
JONES-LINN.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST WEDNESDAY FOR
CEDAR-DES MOINES-HENRY IA-IOWA-JEFFERSON-JOHNSON-KEOKUK-LEE-
LOUISA-MUSCATINE-SCOTT-VAN BUREN-WASHINGTON.
IL...WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR CARROLL-JO
DAVIESS-ROCK ISLAND-STEPHENSON.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT CST WEDNESDAY
NIGHT FOR CARROLL-JO DAVIESS-STEPHENSON.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST WEDNESDAY FOR
ROCK ISLAND.
WINTER STORM WARNING UNTIL 6 PM CST WEDNESDAY FOR BUREAU-HANCOCK-
HENDERSON-HENRY IL-MCDONOUGH-MERCER-PUTNAM-WARREN-WHITESIDE.
MO...WINTER STORM WARNING UNTIL MIDNIGHT CST TONIGHT FOR CLARK-
SCOTLAND.
BLIZZARD WARNING FROM MIDNIGHT TONIGHT TO 6 PM CST WEDNESDAY FOR
CLARK-SCOTLAND.
&&
$$
DLF/12
