Area Forecast Discussion
Issued by NWS Milwaukee/Sullivan, WI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

000
FXUS63 KMKX 232035
AFDMKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
335 PM CDT SAT AUG 23 2014

.TONIGHT AND SUNDAY...FORECAST CONFIDENCE - MEDIUM.

WILL LIKELY SEE SOME SHOWERS LINGER THIS EVENING INTO TONIGHT AS
WEAKENING MCV MEANDERS THROUGH THE AREA...WITH A FEW RUMBLES OF
THUNDER POSSIBLE. THERE WILL BE A LITTLE MORE LOW LEVEL WIND AND
CLOUDS TONIGHT...WITH MODELS ALSO SUGGESTING SLIGHTLY DRIER AIR IN
THE LOW LEVELS. STILL MENTIONED PATCHY FOG...BUT NOT AS CONFIDENT IN
FOG AS THE LAST COUPLE NIGHTS. BETTER CHANCE FOR FOG WILL BE NEAR
LAKE MICHIGAN...WHERE IT MAY BE ADVECTED INLAND FROM THE LAKE.

LOOKS MAINLY DRY SUNDAY...WITH PRECIPITABLE WATER VALUES DOWN FROM 2
INCHES TO AROUND 1.5 INCHES. ALSO...SEEING A BIT OF A CAP IN
SOUNDINGS. MAIN STORY TOMORROW WILL BE THE HEAT...AS TEMPS WILL BE
AROUND 90 IN THE WESTERN HALF OF THE FORECAST AREA...DECREASING TO
LOW 80S NEAR LAKE MICHIGAN UNDER ONSHORE WINDS. WITH DEWPOINTS IN
THE LOW TO MID 70S...EXPECTING HEAT INDEX VALUES OF 95 TO 100 IN THE
WEST TOMORROW. WAS ON THE FENCE FOR A HEAT ADVISORY...BUT HELD OFF
FOR NOW DUE TO SOME UNCERTAINTY IN THE EXTENT OF SUNSHINE AND IF
DEWPOINTS WILL MIX OUT AT ALL.

.SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE - MEDIUM.

STRONGER PERSISTENT DOWNSTREAM RIDGING FROM THE SOUTHERN PLAINS INTO
THE GREAT LAKES AND EASTERN CONUS WL RESULT IN WEAKER STEERING WINDS
ON MONDAY AS WEAK FRONTAL BOUNDARY LIMPS INTO CENTRAL/SRN WI.
PLENTY OF INSTABILITY WITH SBCAPE REACHING 5K J/KG MON AFTN.  MID-
LEVEL LAPSE RATES AROUND 6.5 DEGREES AND BULK SHEAR APPROACHING 35
KTS.  PENDING CLOUD COVER...MAY HAVE ENOUGH INSTABILITY AND SHEAR
FOR A FEW STORMS TO BECOME SEVERE...HOWEVER ANOTHER...MORE IMPORTANT
LIMITING FACTOR WILL BE FORCING AND LIFT ALONG WEAK FRONT.  BOTH NAM
AND GFS DO SHOW WEAK MID-LEVEL SHORT WAVE PROGRESSING ACROSS SRN WI
DURING PEAK HEATING.  LOCAL SEVERE WX CHECKLIST ON THE LOW SIDE...SO
WL HOLD OFF ON MENTIONING SVR POTENTIAL FOR NOW IN HWO.

OTHERWISE...WEAKER MID-LEVEL FLOW WL RESULT IN FRONTAL BOUNDARY
FURTHER WEAKENING ACROSS SRN WI/NRN IL AREA BUT REMAINING AS A
CONVERGENCE ZONE FROM MON NGT THROUGH TUESDAY.  BOTH NAM AND GFS
SHOW SOME WEAK RESPONSE TO FRONTOGENETICAL FORCING ON TUESDAY OVER
SRN WI.  WITH UNSTABLE CONDITIONS CONTINUING THROUGH TUE AND LITTLE
CAPPING...AND GETTING CLIPPED BY WEAK RIGHT ENTRANCE REGION OF
PASSING JET TO THE NORTH...WL CONTINUE CHANCE POPS FOR THE MON NGT
INTO TUE PERIOD.

WITH SLOWER EWD PROGRESSION OF FRONT...TEMPERATURES WL HAVE TIME TO
WARM INTO THE UPPER 80S TO LOWER 90S ACROSS MOST OF THE AREA...WITH
SLIGHTLY COOLER TEMPS RIGHT AT THE LAKESHORE.  HENCE HEAT INDEX
READINGS EXPECTED TO INTO THE MID TO UPPER 90S EVENT OVER CENTRAL
AND WRN PORTIONS OF LAKESHORE COUNTIES.  A FEW INLAND SPOTS MAY
REACH 100.  THE HUMID CONDITIONS WILL CONTINUE ON TUESDAY WITH
SLIGHTLY COOLER DAYTIME TEMPS.

.TUESDAY NIGHT THROUGH SATURDAY...FORECAST CONFIDENCE - MEDIUM
TRENDING TO LOW.

THE THREAT FOR HEAVY RAINFALL AND CONVECTION WILL CONTINUE FROM
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT AS THE STRONG FRONTAL BOUNDARY
WILL REMAIN IN THE VICINITY OF SRN WI/NRN IL.  STILL EXPECT HIGH
PRESSURE TO BUILD IN ACROSS THE NORTHERN GTLAKES BY THURSDAY.
NORTHERLY WINDS ASSOCD WITH THIS FEATURE SHOULD RESULT IN SLIGHTLY
LESS HUMID AIR SPILLING ACROSS SRN WI.  HOWEVER FRONTAL BOUNDARY MAY
REMAIN CLOSE TO SRN WI THROUGH FRI DUE TO MORE PERSISTENT BLOCKING
RIDGE ACROSS CENTRAL INTO ERN CONUS...WHICH IS PARTIALLY DUE TO
TROPICAL DISTURBANCE MOVING SOMEWHERE THROUGH WRN ATLANTIC.  HENCE
WL BE BEEFING UP POPS FROM THU INTO SAT.

BOTH GFS AND ECMWF HINT AT LOW PRESSURE MOVING ALONG THE FRONT
AROUND SATURDAY WITH DRIER CONDITIONS BUILDING IN AFTER
THAT...BUT...ALOT OF UNCERTAINTY WITH REGARDS TO BLOCKING RIDGE AND
AFFECTS FROM DOWNSTREAM TROPICAL SYSTEM SO CONFIDENCE LOW REGARDING
MOST OF THIS FORECAST PERIOD.  DEEP MOISTURE WILL BE IN PLACE
TUESDAY NIGHT INTO THU RESULTING IN HEAVY RAINFALL THREAT.  BEST
CHANCE WILL BE TUESDAY NIGHT AND AGAIN WED NGT WHEN STRONGEST LOW
LEVEL CONVERGENCE IS EXPECTED.

&&

.AVIATION/00Z TAFS/...

WILL LIKELY SEE SOME SHOWERS LINGER THIS EVENING INTO TONIGHT AS
WEAKENING MCV MEANDERS THROUGH THE AREA...WITH A FEW RUMBLES OF
THUNDER POSSIBLE. THERE WILL BE A LITTLE MORE LOW LEVEL WIND AND
CLOUDS TONIGHT...WITH MODELS ALSO SUGGESTING SLIGHTLY DRIER AIR IN
THE LOW LEVELS. STILL MENTIONED PATCHY FOG...BUT NOT AS CONFIDENT IN
FOG AS THE LAST COUPLE NIGHTS. BETTER CHANCE FOR FOG WILL BE NEAR
LAKE MICHIGAN...WHERE IT MAY BE ADVECTED INLAND FROM THE LAKE.

LOOKS MAINLY DRY SUNDAY...WITH VFR CONDITIONS EXPECTED AFTER ANY
LINGERING FOG DISSIPATES.

&&

.MARINE...

A VERY MOIST AIR MASS AND LIGHT WINDS OVER THE RELATIVELY COOLER
WATERS OF LAKE MICHIGAN HAS LED TO CONTINUED DENSE FOG OVER THE
SOUTHEAST WISCONSIN NEARSHORE WATERS OF LAKE MICHIGAN. THE FOG
CONTINUES MAINLY SOUTH OF MILWAUKEE THIS AFTERNOON...SO EXTENDED THE
ADVISORY INTO THE EVENING FOR THE SOUTHERN TWO MARINE ZONES. THERE
MAY BE ANOTHER ROUND OF DENSE FOG ACROSS THE NEARSHORE WATERS LATER
TONIGHT.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...

WI...NONE.
LM...MARINE DENSE FOG ADVY LMZ645-646 UNTIL 03Z/24.

&&

$$

TONIGHT/SUNDAY AND AVIATION/MARINE...DDV
SUNDAY NIGHT THROUGH SATURDAY...MBK


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.