565
FXUS63 KMKX 130822
AFDMKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
322 AM CDT TUE AUG 13 2013
.TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
PATCHY SC ASSOCIATED WITH INITIAL PUSH OF LOW LEVEL COLD AIR
ADVECTION DIMINISHING AND PUSHING RAPIDLY SOUTHWEST IN INCREASING
LOW LEVEL N-NE FLOW. REINFORCING PUSH OF LOW LEVEL COLD AIR THIS
MRNG AND LINGERING CYCLONIC FLOW AND MOISTURE SHOULD RESULT IN
PERIOD OF SCT-BKN CU REDEVELOPING LATER THIS MRNG INTO THE EARLY
AFTN. THERMAL TROUGH WEAKENS DURING THE AFTN AS LOW LEVEL FLOW
BECOMES A BIT MORE N-NW...HENCE SHOULD TREND TOWARD MORE SUNSHINE
DURING THE AFTN.
1000-850MB WINDS REMAIN NORTHERLY TODAY AND TONIGHT AS DELTA-T
INCREASES TO AROUND 14C. HENCE MORE WIDESPREAD AND PERSISTENT CU
LIKELY TO REMAIN FARTHER SOUTH OVER NRN IL/IN.
COOL AIR IN PLACE AND STRONGER ONSHORE FLOW SHOULD KEEP
TEMPERATURES NOTICEABLY COOLER THAN MON. TEMPS WL PEAK IN THE
UPPER 60S TO LOWER 70S MOST AREAS.
QUITE A BIT OF UPSTREAM CLOUDINESS OVER/NORTH OF LAKE SUPERIOR.
EXPECT SOME OF THIS CLOUDINESS TO SPREAD SOUTH AND MAY AFFECT
PARTS OF SRN WI LATE AFTN/EVE. HOWEVER CLOUDS WL BE FIGHTING
AGAINST INCREASING SUBSIDENCE FROM LEFT ENTRANCE REGION OF SAGGING
UPPER JET.
HENCE WL TREND TOWARD OVERNIGHT CLEARING AND PATCHY LATE NIGHT FOG
IN LOW AREAS AND RIVER VALLEY. MODERATE TO STRONG LATE NIGHT
INVERSION WL ALLOW OVERNIGHT TEMPS TO FALL INTO THE MID 40S MOST
AREAS AWAY FROM THE LAKE. MAY BE A FEW LOWER 40S IN FAVORABLE
DRAINAGE AREAS.
.WEDNESDAY THROUGH THURSDAY NIGHT...FORECAST CONFIDENCE IS HIGH.
SHORT TERM MODELS IN GOOD AGREEMENT WITH HIGH PRESSURE OVER THE
AREA ON WEDNESDAY SLIDING SLOWLY TO THE SOUTHEAST WEDNESDAY NIGHT
INTO THURSDAY NIGHT. 500MB FLOW REMAINS NORTHWESTERLY ACROSS THE
REGION DURING THIS TIME...WITH VERY WEAK VORTICITY MAXIMA PUSHING
THROUGH AT TIMES.
AREA FORECAST SOUNDINGS REMAIN FAIRLY DRY DURING THIS TIME.
THUS...WILL KEEP DRY FORECAST GOING DURING THIS PERIOD. SHOULD SEE
SOME FOG DEVELOP IN THE TYPICAL LOW LYING AREAS WEDNESDAY NIGHT
AND THURSDAY NIGHT...AS TEMPERATURES FALL TO NEAR/AT DEW POINT
VALUES.
SOME DIURNAL CUMULUS CLOUDS ARE EXPECTED WEDNESDAY AND THURSDAY
AFTERNOON...WITH WEAK INSTABILITY ON FORECAST SOUNDINGS. SLOW BUT
STEADY WARM AIR ADVECTION WILL BRING GRADUALLY MODERATING
TEMPERATURES...INCREASING TO NEAR SEASONAL NORMALS THURSDAY INTO
THURSDAY NIGHT.
.FRIDAY THROUGH MONDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
GFS/ECMWF MODELS ARE IN GOOD AGREEMENT WITH FEATURES DURING THIS
PERIOD. THEY SHOW THE HIGH TO THE EAST OF THE REGION CONTINUES ITS
SLOW MOVEMENT...AND KEEPS ITS INFLUENCE ACROSS THE AREA. 500MB
FLOW SHIFTS FROM NORTHWESTERLY FRIDAY TO WEAK RIDGING LATER IN THE
WEEKEND. ECMWF QUICKER WITH THE RIDGE MOVING INTO THE REGION THAN
THE GFS.
GFS FORECAST SOUNDINGS REMAIN FAIRLY DRY THROUGH THIS PERIOD AS
WELL. THUS...WILL CONTINUE THE DRY FORECAST DURING THIS PERIOD.
TEMPERATURES WILL CONTINUE TO MODERATE DURING THIS TIME...AS A
SLIGHTLY WARMER AIRMASS SHIFTS INTO THE REGION.
&&
.AVIATION/12Z TAFS/...ENOUGH LINGERING LOW LEVEL MOISTURE AND COLD
AIR ALOFT TO RESULT IN A PERIOD OF BKN VFR CIGS LATER THIS MRNG
MOST AREAS. WARMING LOW LEVELS AND MIXING SHOULD CAUSE DECREASING
CU DURING THE AFTN. PATCHY VFR CLOUDS MAY LINGER INTO THE EVENING
AS SECONDARY WEAK BOUNDARY SLIDES THRU SRN WI. PATCHY LATE NIGHT
FOG IN SUSCEPTIBLE AREAS EXPECTED.
&&
.MARINE...STRONGEST WIND GUSTS EXPECTED THIS MORNING AS CORE OF
LOW LEVEL COLD AIR ADVECTION SWINGS THROUGH...THEN SHOULD TAPER
OFF LATE MORNING INTO THE AFTERNOON AS THERMAL TROUGH BEGINS TO
WEAKEN. WL CONTINUE SMALL CRAFT ADVY MOST AREAS THRU THE AFTN TO
ACCOUNT FOR SLOWLY SUBSIDING WAVE HEIGHTS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ644>646.
SMALL CRAFT ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LMZ643.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...MBK
WEDNESDAY THROUGH MONDAY...WOOD