FXUS63 KMKX 272124
AFDMKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
324 PM CST FRI NOV 27 2009
.SHORT TERM...
TONIGHT...FORECAST CONFIDENCE: HIGH
HIGH PRESSURE OVER THE CENTRAL US WILL ALLOW FOR CONTINUED QUIET
WEATHER TONIGHT. A FEW CIRRUS CLOUDS COULD STREAM ACROSS THE AREA
OVERNIGHT...BUT SHOULD BE THIN AND NOT INHIBIT TEMPS FROM DROPPING
INTO THE MID TO UPPER 20S. TEMPS RIGHT ALONG THE LAKESHORE SHOULD
STAY SLIGHTLY WARMER. MODIS IMAGERY SHOWS WATER TEMPS ALONG THE
SHORE ARE AROUND 43F. WINDS WILL BE LIGHT AND GENERALLY OUT OF THE
SOUTH. 925MB TEMPS WILL BEGIN WARMING WITH THE RETURN FLOW AROUND
THE HIGH.
SATURDAY...FORECAST CONFIDENCE: HIGH
A WEAK LOW PRESSURE AREA DEVELOPING OVER THE NORTHERN PLAINS WILL
DRIFT ACROSS THE UPPER MIDWEST ON SATURDAY AND HELP TO USHER IN MILD
TEMPS ACROSS THE SOUTHERN HALF OF THE STATE. HIGHER CLOUDS WILL
LIKELY SPREAD ACROSS THE AREA IN THE AFTERNOON. WITH 925MB TEMPS
WARMING TO +5C OR BETTER...AND BUFKIT MODEL SNDGS SHOW MIXING TO
ALMOST THAT HIGH...MAX TEMPS SHOULD NEAR 50 AT MOST LOCATIONS IN THE
SOUTHERN CWA...AND WILL BE IN THE UPPER 40S IN THE NORTHERN CWA.
SAT NIGHT SHOULD STAY FAIRLY MILD...WITH LOWS AROUND 30...WARMER
NEAR THE LAKESHORE.
SUNDAY...FORECAST CONFIDENCE: MEDIUM
THE WEAK SFC LOW WILL CROSS WI ON SUNDAY. IT WILL DRAG A COLD FRONT
DOWN ACROSS CENTRAL IL AND MO. COLD AIR WILL FLOW INTO THE STATE ON
NORTHWEST WINDS BEHIND THE WEAK SFC LOW DURING THE DAY ON SUNDAY. A
500MB SHORTWAVE CROSSING THE UPPER MIDWEST WILL BRING A GOOD AMOUNT
OF CLOUDS AND THE POSSIBILITY OF SOME FLURRIES TO THE STATE. 925MB
TEMPS WILL BE JUST BELOW FREEZING AND SFC TEMPS WILL BE JUST ABOVE
FREEZING...SO WHETHER IT WILL BE FLURRIES OR SPRINKLES IS STILL
UNCERTAIN. THE FAR SOUTHEAST CWA WILL BE CLOSEST TO THE SFC FRONT
AND THEREFORE HAS A SLIGHTLY BETTER CHANCE AT GETTING PRECIP. IT
SHOULD BE IN THE FORM OF RAIN SINCE TEMPS WILL BE WARMER IN THAT
AREA.
.LONG TERM...
MONDAY...FORECAST CONFIDENCE: MEDIUM
MODELS BEGIN TO DIVERGE IN SOLUTIONS ON THIS DAY. THE ECMWF
DIGS A POTENT SHORTWAVE ACROSS THE MN ARROWHEAD ON MON WHILE THE GFS
HAS A WEAKER SHORTWAVE THAT GETS MASKED BY THE STRONG RIDGING OVER
THE NORTHERN PLAINS. BOTH MODELS GENERATE A SFC LOW IN THE FAR
NORTHEAST US WITH A TRAILING COLD FRONT DOWN ACROSS THE SOUTHEASTERN
US. GENERAL LIGHT PRECIP IS POSSIBLE ON MONDAY AND MONDAY NIGHT
ACROSS NORTHERN WI WITH THE SHORTWAVE ENERGY...BUT SOUTHERN WI
SHOULD REMAIN DRY WITH SOME CLOUDS.
TUESDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE: MEDIUM
THE MODELS CONTINUE TO DIVERGE. HOWEVER...BOTH AGREE THAT SOUTHERN
WI WILL REMAIN DRY. THERE IS STILL UNCERTAINTY IN TEMPERATURES SINCE
THE ECMWF PREFERS MORE SOUTHERLY WINDS AND 925MB TEMPS AROUND
+4C...AND THE GFS IS MORE WESTERLY WITH COOLER 925MB TEMPS.
BOTH MODELS SHOW A CLOSED UPPER LOW OVER THE TEXAS/MEXICO BORDER AT
00Z WED THAT SCOOTS ACROSS TEXAS ON WED. THEY ALSO SHOW ANOTHER
POTENT 500MB SHORTWAVE TRACKING ACROSS THE US/CANADIAN BORDER. THE
GFS IS FASTER WITH THE MOVEMENT OF THAT SHORTWAVE THAN THE ECMWF.
THURSDAY AND FRIDAY...FORECAST CONFIDENCE: LOW
THE DIFFERENCE BETWEEN THE MODELS IS LESSENING WITH THE LATEST 12Z
MODEL RUNS. ON WED NIGHT AND THURSDAY...THE GFS OPENS UP THE UPPER
WAVE OVER THE SOUTHEAST STATES AND LETS IT GET SWALLOWED UP BY THE
GENERAL LARGE SCALE UPPER TROUGH AND RIDE QUICKLY UP THE EAST COAST
THROUGH THU NIGHT...ALLOWING SFC HIGH PRESSURE TO BUILD INTO THE
MIDWEST. THE ECMWF NOW ALSO ALLOWS THE SOUTHERN-STREAM CLOSED UPPER
LOW TO ABSORB INTO THE MAINSTREAM TROUGH OVER THE EAST COAST...JUST
TO A LESSER DEGREE AND DIFFERENT TIMING.
THE BIGGER DIFFERENCE IS THE SPEED OF THE SHORTWAVE TREKKING ACROSS
THE NORTHERN US BORDER. THE CANADIAN GEM MODEL IS SLOWEST...AND THE
ECMWF STILL REMAINS SLOWER THAN THE GFS. AFTER THE TWO SHORTWAVES
MERGE OVER THE EAST COAST...THE ECMWF AND GEM DEVELOP A LARGE CLOSED
SFC LOW IN THE NORTHEAST US. THE EXPANSIVE LOW COULD HAVE PRECIP
WRAPPING AROUND IT AS FAR WEST AS MN. COLD TEMPS BEING PULLED DOWN
BY THE UPPER LOW SHOULD ALLOW PRECIP TYPE TO BE ALL SNOW ACROSS WI
EXCEPT THE FAR SOUTHEAST. IF GFS IS RIGHT...WI WOULD NOT GET ANY
PRECIP. STAY TUNED...
&&
.AVIATION...
NO PROBLEMS WITH CEILINGS EXPECTED THROUGH SATURDAY. PATCHES OF
HIGH CLOUDS EXPECTED THROUGH THIS EVENING. MODELS DO SHOW
INCREASING MOISTURE IN THE LOWEST 2000 FEET LATE TONIGHT...BUT
PROBABLY NOT ENOUGH FOR LOW CLOUD DEVELOPMENT. SPOTTY MVFR
VISIBILITY IN LIGHT FOG APPEARS LIKELY WITH LIGHT WINDS AND STILL
LOTS OF SOIL MOISTURE FROM RECENT RAINS.
&&
.MARINE...
QUIET CONDITIONS WILL CONTINUE THROUGH SATURDAY WITH WAVES SUBSIDING
FROM YESTERDAYS HIGH LEVELS. LIGHT WINDS EXPECTED UNDER WEAK
SURFACE HIGH PRESSURE RIDGE.
COLD FRONT MOVES THROUGH SUNDAY...WITH LOW STARTING TO DEEPEN ALONG
THE FRONT OVER LOWER MICHIGAN LATER SUNDAY AND SUNDAY NIGHT. THIS
COULD RESULT IN MARGINAL SMALL CRAFT ADVISORY CONDITIONS ON BRISK
NORTHWEST WINDS.
ANOTHER STRONG LOW PRESSURE SYSTEM COULD MOVE ACROSS SOUTHERN CANADA
TUESDAY AND WEDNESDAY...RESULTING IN A PERIOD OF STRONG SOUTHWEST
WINDS TUESDAY AND WEST WINDS ON WEDNESDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
SHORT/LONG TERM...13/MRC
AVIATION/MARINE...02/JPC