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 060254 AAA
AFDMKX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI
854 PM CST THU MAR 5 2015

.UPDATE...
LITTLE TO ADJUST WITH CLEAR SKIES AND TEMPS CLOSE TO FORECAST
TRENDS. ONLY A SMALL POCKET OF MID-HIGH LEVEL CLOUDS WITH SHORT
WAVE OVER FAR SE SOUTH DAKOTA/NORTHEAST NEBRASKA...WITH THE WAVE
EXPECTED TO TRACK ACROSS IOWA INTO WEST CENTRAL IL OVERNIGHT.

ENOUGH GRADIENT OVER SRN WI WITH CORE OF SURFACE HIGH MOVING EAST
OVER CENTRAL IL TO PRODUCE SOME WIND CHILLS...WHICH BOTTOM OUT
BETWEEN -11 AND -18 DURING THE MID-OVERNIGHT HOURS THEN RISE WITH
SLOWLY WARMING TEMPERATURES ON DEVELOPING SOUTHERLY WINDS.

&&

.AVIATION/06Z TAFS/...

VFR CONDITIONS THROUGH THE FORECAST...WITH GUSTY WINDS UP TO 25
KNOTS DEVELOPING DURING THE LATE MORNING FRIDAY AND LASTING
THROUGH THE REST OF THE DAYLIGHT HOURS. 21Z SREF ALONE IN SHOWING
ANY QPF MOVING INTO THE AREA FRIDAY AFTERNOON/EVENING WITH WEAK
TROUGH. LATEST NAM SIMULATED REFLECTIVITY INDICATING THE POTENTIAL
FOR SOME FLURRIES...BUT FORECAST SOUNDINGS SHOW A SHALLOW CLOUD
LAYER SO WILL NOT PUT ANY SNOW IN TAFS...AND WOULD LEAN TOWARD
ISOLATED FLURRIES WITH NO VSBY REDUCTION AT WORST.

&&

.MARINE...

LATEST NAM SUPPORTING INCREASING SOUTHERLY WINDS BY MID-MORNING
AHEAD OF A WEAK SURFACE TROUGH AND CONTINUING THROUGH THE
DAYLIGHT HOURS. WINDS WILL DECREASE THROUGH THE LATE
AFTERNOON/EARLY EVENING AS BAGGY GRADIENT WITH THE TROUGH MOVES
OVER THE NEARSHORE WATERS. NO CHANGE TO SMALL CRAFT ADVISORY AT
THIS TIME.

&&

.PREV DISCUSSION... /ISSUED 324 PM CST THU MAR 5 2015/

SHORT TERM...

TONIGHT AND FRIDAY... FORECAST CONFIDENCE MEDIUM.

A STRONG 190KT 250 MB JET CORE FROM THE MID MISSISSIPPI VALLEY TO
THE EASTERN GREAT LAKES WILL MOVE OFF TO THE EAST. SLIGHT 500 MB
RIDGING ALONG WITH NEGATIVE VORTICITY ADVECTION WILL TRANSLATE OVER
THE STATE DURING THE EVENING AND OVERNIGHT HOURS...KEEPING SKIES
CLEAR TO MOSTLY CLEAR TONIGHT. SFC HIGH PRESSURE WILL QUICKLY MOVE
THROUGH THE REGION LATER TONIGHT INTO EARLY FRIDAY AS WELL.

A 500MB SHORTWAVE TROUGH DOES MOVE INTO THE REGION DURING THE FRIDAY
MORNING HOURS...WITH A DECENT VORTICITY MAXIMUM ASSOCIATED WITH IT.
THERE IS SOME UNCERTAINTY REGARDING FLURRIES DURING THE MORNING AND
EARLY AFTERNOON HOURS AS THIS SHORTWAVE MOVES THROUGH. NAM BUFKIT
SOUNDINGS SHOW SOME DECENT MOISTENING IN THE LOWER LEVELS...WITH A
STEEPENING LOW LEVEL LAPSE RATE. THERE DOES NOT APPEAR TO BE MUCH IN
THE WAY OF QPF WITH THIS SYSTEM. HOWEVER...KEPT ISOLATED CHANCES OF
FLURRIES IN THE GRIDS DUE TO THE MID LEVEL SUPPORT ALONG WITH THE
STEEPER LAPSE RATES AND FAIRLY MOIST LOW LEVELS.

SOUTHWEST SFC WINDS ALONG WITH SOME STRONG LOW LEVEL WARM AIR
ADVECTION WILL BRING HIGHS FRIDAY INTO THE 30S AND EVEN ABOVE
FREEZING IN SOME LOCATIONS IN OUR FAR WESTERN COUNTIES. GFS AND
ECMWF 925 MB TEMPERATURES WILL BE NEAR -9C BY 18Z FRIDAY...WITH EVEN
WARMER TEMPERATURES INTO THE AFTERNOON HOURS FRIDAY. TIGHTENING SFC
PRESSURE GRADIENT WILL RESULT IN STRONG WINDS FOR FRIDAY...WITH
GUSTS REACHING INTO THE LOWER TO MID 20KT ACROSS THE FORECAST AREA.

FRIDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE MEDIUM.

SWLY FLOW AND WEAK LOW TO MID LEVEL WARM ADVECTION WILL CONTINUE
FRI NT INTO SAT. THE SWLY FLOW IS AHEAD OF A LOW PRESSURE AREA
THAT WILL TRACK ACROSS THE NRN GREAT LAKES FROM LATE FRI NT
THROUGH SAT. THUS A COLD FRONTAL PASSAGE IS EXPECTED ON SAT BUT
OVERALL COLD ADVECTION WILL BE WEAK. THE AFOREMENTIONED WARM
ADVECTION AND A SHORTWAVE TROUGH THAT WILL TRACK FROM NRN IA
ACROSS NRN IL SAT AM...WILL BRING A PERIOD OF CLOUDS AND PERHAPS
VERY LIGHT PCPN. SOME FCST SOUNDINGS DO ATTEMPT TO SATURATE THE
LOW LEVELS FOR A BRIEF TIME...BUT THE OMEGA QUICKLY WEAKENS WITH
DRYING IN THE MID LEVELS. WILL MAINTAIN A DRY FCST FOR NOW BUT
NON MEASURABLE PCPN IS POSSIBLE. THE PERSISTENT WARM ADVECTION
FROM FRI INTO SAT SHOULD BE ABLE TO BOOST HIGH TEMPS INTO THE
LOWER 40S FOR SOME LOCATIONS.

THE MODELS THEN DISAGREE ON A CLIPPER SYSTEM FOR SUN WITH THE
ECMWF AND CANADIAN SPREADING A SWATH OF LGT SNOW ACROSS THE AREA
WHILE THE GFS AND NAM IS WEAKER AND FARTHER SOUTH. DID INCREASE
POPS TO 30-40 PERCENT. THE WARM ADVECTION FROM THE CLIPPER WILL
LIKELY BOOST TEMPS INTO THE MID-UPPER 30S FOR SUN AFT.

LONG TERM...

MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE MEDIUM.

A PATTERN CHANGE WILL FINALLY OCCUR WITH A SPLIT JET STREAM FLOW
DEVELOPING. THE NRN JET WILL BE MAINLY IN SRN CANADA AND ZONAL
WITH THE SRN JET OVER THE FAR SRN USA. THUS SWLY SFC FLOW AND
PERSISTENT WARM ADVECTION IS EXPECTED THROUGH AT LEAST WED.
1000-500 MB THICKNESSES AND SFC TEMPS WILL RISE EACH DAY WITH
WIDESPREAD 50S FOR HIGHS BY WED. THE MODELS THEN DIFFER ON THE
PASSAGE OF A WEAKENING COLD FRONT FROM THE NORTH FOR WED NT AND
THU. NO PCPN IS FORECAST.

AVIATION/00Z TAFS/...

VFR CONDITIONS WILL CONTINUE INTO THE EVENING HOURS AS AN AREA OF
HIGH PRESSURE STAYS SITUATED OVER THE REGION INTO THE EARLY HOURS
FRIDAY. CLEAR TO MOSTLY CLEAR SKIES WILL PERSIST INTO THE EVENING
HOURS. WINDS WILL CONTINUE TO TURN TO A MORE SOUTHWESTERLY DIRECTION
THIS EVENING AND OVERNIGHT AS THE AREA OF HIGH PRESSURE MOVES OFF TO
THE SOUTHEAST EARLY FRIDAY. EXPECT STRONG WIND GUSTS DURING THE DAY
FRIDAY AS THE SURFACE PRESSURE GRADIENT TIGHTENS. GUSTS FRIDAY COULD
REACH INTO THE LOWER TO MID 20KT.

MARINE...

HIGH PRESSURE WILL BE SITUATED OVER THE REGION TONIGHT INTO EARLY
FRIDAY UNTIL IT MOVES OFF TO THE SOUTHEAST BY LATER IN THE DAY
FRIDAY. THE SURFACE PRESSURE GRADIENT WILL TIGHTEN FRIDAY...LEADING
TO STRONG WINDS DURING THE DAY WITH GUSTS OVER 22KT. AS A
RESULT...ISSUED A SMALL CRAFT ADVISORY FOR NEARSHORE
WATERS...EFFECTIVE BETWEEN 13Z FRI AND 03Z SAT.

&&

.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 AM TO 9 PM CST FRIDAY FOR LMZ643>646.

&&

$$

UPDATE...REM
TONIGHT/FRIDAY AND AVIATION/MARINE...JTS
FRIDAY NIGHT THROUGH THURSDAY...GEHRING



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