000
FXUS63 KGRB 162046
AFDGRB
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREEN BAY WI
346 PM CDT TUE MAR 16 2010
.SHORT TERM...TONIGHT AND WEDNESDAY. LATEST RUC ANALYSIS AND
VIS/IR/WV/RADAR IMAGERY SHOW WISCONSIN LOCATED BETWEEN HIGH PRESSURE
CENTERED OVER THE NORTHERN PLAINS AND LOW PRESSURE OFF THE COAST OF
THE MID-ATLANTIC STATES. A COUPLE OF WEAK SHORTWAVES ARE TRAVERSING
ACROSS THE REGION. ONE IS DROPPING SOUTH ACROSS MINNESOTA...WITH AN
AREA OF SHOWERS MOVING ALONG THE MINNESOTA/WISCONSIN BORDER.
ANOTHER WEAK WAVE IS MOVING INTO SW WISCONSIN WITH ONLY SCT
MID-LEVEL CLOUDS. DRY EASTERLY FLOW IS KEEPING THE EFFECTS OF BOTH
SYSTEM AT BAY...WITH MOSTLY CLEAR SKIES PRESENT ACROSS THE MAJORITY
OF THE AREA. FORECAST CONCERNS ARE MINIMAL OVER THE NEXT 24
HOURS...NAMELY TEMPS AND DEWPOINTS.
HIGH PRESSURE WILL CONTINUE TO SLOWLY BUILD INTO THE REGION AT THE
SURFACE TONIGHT. AS THE PREVIOUSLY MENTIONED SHORTWAVES
DEPART/WEAKEN...WILL SEE DRYING OCCUR AT THE MID-LEVELS WHICH WILL
LEAD TO MOSTLY CLEAR SKIES BY LATE IN THE EVENING. SHOULD SEE A
FAIRLY LARGE TEMPERATURE DROP WITH THE GOOD RADIATIONAL COOLING
CONDITIONS PRESENT...AND WILL LOWER MIN TEMPS. WENT WITH A COMBO OF
PERSISTENCE AND MOSG FOR LOWS TONIGHT.
HIGH PRESSURE WILL BE PRESENT ALOFT AND AT THE SURFACE
TOMORROW...MEANING LOTS MORE SUNSHINE. BOTH THE ECMWF AND NAM HAVE
SIMILAR TEMPERATURE PROFILES AT 925MB AT 00Z FOR TOMORROW. SO USED
THESE MODELS FOR HIGHS...WHICH WILL RANGE FROM THE UPPER 50S OVER
N-C WISCONSIN...TO THE MID 60S IN THE DOWNSLOPING AREAS OF NE
WISCONSIN.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY...MAIN FCST
CONCERNS ARE UNSEASONABLY WARM TEMPERATURES EARLY IN THE
PERIOD...AND PCPN TRENDS AND TYPE FOR THE WEEKEND.
AS ADVERTISED FOR THE PAST SEVERAL DAYS...THURSDAY IS SHAPING UP AS
PERHAPS THE WARMEST DAY OF THE WEEK. WITH H8 TEMPS AROUND +8 C...
WESTERLY DOWNSLOPE WINDS...AND COMPRESSIONAL HEATING ALONG/AHEAD OF
THE COLD FRONT...DEEP MIXING SHOULD BOOST TEMPS TO NEAR 70 FROM
WAUPACA TO KESHENA. THIS IS SUBSTANTIALLY WARMER THAN GUIDANCE
SUGGESTS...BUT MODELS HAVE BEEN CONSISTENTLY TOO COOL FOR SEVERAL
DAYS. TEMPS WILL DROP BACK 10 TO 15 DEGREES ON FRIDAY IN THE WAKE
OF THE FRONT...BUT WILL STILL BE WELL ABOVE NORMAL HIGHS FOR MID-
MARCH.
MODELS HAVE BEEN FAIRLY CONSISTENT BRINGING POST-FRONTAL LGT RAIN
INTO CNTRL WI ON FRIDAY AFTERNOON...THEN SPREADING IT ACROSS THE
REST OF THE CWA FRIDAY EVG. LLVL THERMAL FIELDS/THICKNESSES AND
WET BULB TEMPS SUPPORT PCPN MIXING...WITH THEN CHANGING OVER TO
SNOW FROM NW TO SE DURING THE OVERNIGHT PERIOD. DIFFERENCES
CONTINUE TO SHOW UP OVER THE WEEKEND...WITH THE GFS LINGERING MDT
TO HEAVY PCPN THROUGH THE WEEKEND...AND SUGGESTING THE POTENTIAL
FOR HEAVY SNOW OVER THE RGN. THE FAVORED ECMWF...WHICH HAS BEEN
CONSISTENT FOR THE PAST THREE MODEL RUNS...IS MORE PROGRESSIVE
WITH THE PCPN...AND FOCUSES MDT QPF OVER MAINLY EC WI FRI NGT INTO
SAT NGT. THE CANADIAN AND GFS ENSEMBLE MEAN IS MORE SUPPORTIVE OF
THE ECMWF SOLN...SO WILL CONTINUE TO SIDE WITH THE ECMWF FOR THE
WEEKEND FCST. AS A HEDGE... WILL MAKE MENTION OF THE POSSIBILITY
OF SOME MINOR SNOW ACCUMS OVER PARTS OF C/EC WI THIS WEEKEND IN
THE HAZARDOUS WEATHER OUTLOOK.
MUCH COOLER TEMPS WILL BE THE RULE FOR THE WEEKEND AND EARLY NEXT
WEEK. A BRIEF PERIOD OF WEAK LK-EFFECT SNOW IS PSBL IN FAR NC WI
SUNDAY NGT INTO EARLY MONDAY. ANOTHER LOW PRESSURE SYSTEM IS
EXPECTED TO TRACK THROUGH MN/N WI ON TUESDAY...BRINGING THE
POTENTIAL FOR ANOTHER ROUND OF LGT MIXED PCPN.
&&
.AVIATION...VFR CONDITIONS EXPECTED THROUGH WEDNESDAY WITH ONLY A
SCATTERING OF MID OR HIGH CLOUDS THROUGH THIS EVENING BEFORE
CLEARING OCCURS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/TSK
