FXUS63 KMKX 042153
AFDMKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
353 PM CST FRI DEC 4 2009
BREAK IN CLOUD COVER WITH MAINLY DIURNAL CU OVER SRN WI FILLING IN
AS SHORT WAVE OVER NRN MN DIVES SOUTH TOWARDS REGION. HIGH
TEMPERATURES STRUGGLED INTO THE LOW TO MID 20S IN SPITE OF SOME
SUNSHINE.
.SHORT TERM/TONIGHT THROUGH MONDAY/...
.TONIGHT...CONFIDENCE: HIGH.
WILL KEEP CLOUDS AND FLURRIES IN FORECAST AS ENHANCED CLOUDS ON
WATER VAPOR LOOPS SWING SOUTHEAST TONIGHT. STRONGEST LAYER Q-VECTOR
CONVERGENCE REMAINS NORTH SO NO MEASURABLE EXPECTED. WENT WITH
COLDER MET GUIDANCE THAT IS VERIFYING WELL AT BOTH MADISON AND
MILWAUKEE FOR LOWS TONIGHT IN SPITE OF CLOUD COVER...WITH COLD AIR
ADVECTION CONTINUING TO COOL TEMPS IN SPITE OF CLOUD BLANKET.
.SATURDAY INTO SUNDAY...CONFIDENCE: HIGH.
HIGH PRESSURE KEEPS MOST OF THIS PART OF THE WEEKEND DRY. MIXING UP
TO -7C TO -8C 925 MB TEMPS YIELDS UPPER 20S TO AROUND 30 FOR
SATURDAY HIGHS...AGAIN THE MET IS FAVORED. WAA OVERNIGHT SATURDAY
INTO SUNDAY...WITH MOS GUIDANCE IN LINE WITH LOW 20S FOR LOWS...AND
LOW TO MID 30S FOR HIGHS.
.SUNDAY NIGHT AND MONDAY...CONFIDENCE: MEDIUM.
NEXT ACCUMULATING SNOW COMES SUNDAY NIGHT INTO MONDAY AS SHORT WAVE
CURRENTLY DIVING SOUTHEAST OUT OF BRITISH COLUMBIA EJECTS OUT OF THE
ROCKIES AND INTO THE MIDWEST SUNDAY NIGHT. GFS AND CANADIAN KEEP
FORCING AND PCPN SOUTH ACROSS NRN IL...BUT GFS ENSEMBLES UKMET AND
ECMWF AS WELL AS SREF BRING A SWATH OF PCPN ACROSS THE SOUTH SO UPPED
POPS TO LIKELY BETWEEN 06Z AND 12Z FOR ABOUT 2 TO 3 INCHES OF SNOW.
SOME LAKE ENHANCEMENT POSSIBLE OVERNIGHT SUNDAY AS NE WINDS OFF LAKE
CONVERGE WITH NNW WINDS OVER LAND.
.LONG TERM/MONDAY NIGHT THROUGH FRIDAY/...
.MONDAY NIGHT INTO TUESDAY...CONFIDENCE: MEDIUM.
HIGH PRESSURE NOSES INTO REGION BETWEEN DEPARTING LOW AND NEXT LOW
DEVELOPING OVER THE SRN PLAINS MONDAY NIGHT. PCPN WILL PUSH INTO THE
WEST TUESDAY MORNING...AND THE EAST IN THE AFTERNOON BUT BULK OF
PCPN EXPECTED AFTER 00Z TUE..
.TUESDAY AFTERNOON THROUGH WEDNESDAY...CONFIDENCE: LOW.
THE 00Z ECMWF REALLY BOMBED THE SFC LOW FOR TUESDAY NIGHT INTO
WEDNESDAY...A 30 MB DROP IN 24 HOURS...AS IT LIFTED THROUGH OUR
REGION TUESDAY NIGHT INTO WEDNESDAY...BUT THE 12Z RUN HAS BACKED OFF
AMOUNT OF DEEPENING AND NOW TAKES A PATH UP THE OHIO RIVER VALLEY.
INVERTED TROUGH EXTENDING BACK TO THE NORTHWEST OVER ERN WI AND LAKE
MI AND LAKE ENHANCEMENT POTENTIAL STILL BRINGS 12Z GFS HAS A MORE
OMINOUS ST LOUIS TO SOUTH BEND TRACK. WILL HOLD SERVE ON CURRENT
FORECAST...AND HIGHLIGHT IN THE HWO WITH LOW CONFIDENCE IN TRACK AND
AMOUNTS. WILL BE BLUSTERY AS LOW DEEPENS TO OUR EAST...WITH BLOWING
SNOW A POSSIBILITY.
.WEDNESDAY NIGHT THROUGH FRIDAY...CONFIDENCE: LOW.
GFS IS SLOWER THAN PREFERRED ECMWF ENDING THE SNOW WEDNESDAY NIGHT
FROM SW TO NE...BUT WILL KEEP WEDNESDAY NIGHT DRY. HIGH BRINGS DRY
WEATHER BUT BELOW NORMAL TEMPS THURSDAY AND FRIDAY. AGAIN
VARIABILITY IN TRACK AND TIMING GIVES A LOW CONFIDENCE PCPN FORECAST
WITH ONLY SLIGHT CHANCE FOR NOW.
&&
.AVIATION...LARGE SHIELD OF CLOUDS ROTATING AROUND LOW PRESSURE IN
ONTARIO IS EXPECTED TO REMAIN INTACT OVERNIGHT. COLD AIR ALOFT WILL
CONTINUE TO GENERATE STEEP LOW LEVEL LAPSE RATES THIS EVENING AND
SUPPORT CONTINUED MVFR CIGS AND SCATTERED FLURRIES THROUGH AT LEAST
06Z. WEAK RIDGING PUSHES IN EARLY SATURDAY AND WOULD EXPECT THE
STRATUS TO EVENTUALLY SCOUR. THE DRIER AIR SHOULD FINALLY WORK ITS
WAY INTO SOUTHERN WISCONSIN BY SATURDAY AFTERNOON...ALLOWING
SCATTERED VFR CLOUDS OR CLEAR SKIES.
NON-CONVECTIVE LLWS LIKELY SAT NIGHT.
&&
.MARINE...CONDITIONS APPROACHING SMALL CRAFT ADVISORY LEVELS WILL
CONTINUE THIS EVENING AS THE PRESSURE GRADIENT REMAINS TIGHT ACROSS
THE AREA. HOWEVER...IT APPEARS WINDS WILL STAY JUST BELOW THRESHOLD
AND DUE TO THE OFF SHORE NATURE OF THE WIND...WAVES WILL LIKELY STAY
BELOW CRITERIA AS WELL. ANY SMALL BOATS OUT THERE SHOULD STILL
EXERCISE CAUTION. WINDS ARE EXPECTED TO REMAIN ELEVATED THROUGH
SUNDAY MORNING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
SHORT/LONG TERM...09
AVIATION/MARINE...13
