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000
FXUS63 KDLH 101521
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
921 AM CST WED FEB 10 2010

.UPDATE...CANADIAN SFC HIGH NOSING INTO THE FA WITH A CLEAR SKY
OVER NE MN AND CLEARING UNDERWAY IN NW WI. GENERAL NORTHERLY FLOW
OVER LAKE SUPERIOR RESULTING IN CLOUDS STREAMING OVER THE WI FA.
HOWEVER...THE DRIER AIR IS ALLOWING SOLAR TO ERODE AWAY THE
CLOUDS. HAVE REMOVED THE POPS IN NW WI. LEFT MAX TEMPS AS IS.

&&

.PREV DISCUSSION... /ISSUED 548 AM CST WED FEB 10 2010/

AVIATION...12Z TAF ISSUANCE...
RIDGE OF HIGH PRESSURE AT THE SURFACE AND THE LACK OF ANY
DISTURBANCES ALOFT SHOULD KEEP GENERALLY CLEAR CONDITIONS AT ALL
TAF SITES EXCEPT KHYR. A FEW THIN HIGH CLOUDS ARE POSSIBLE SO WILL
LEAVE THOSE IN INHERITED FCSTS. KHYR IS BEING AFFECTED BY NRLY
WIND OFF LAKE SUPERIOR SO MVFR CLOUD DECK IS NOT MOVING MUCH.
LATEST SAT ANIMATION SHOWS BACK EDGE OF CLOUD DECK HAS DRIFTED
WEST OVERNIGHT. USING NAM12 COND PRESS DEFICIT IT APPEARS THAT THE
CEILING MAY LIFT WITH DAYTIME WARMING....BUT REMAIN MVFR.

PREV DISCUSSION... /ISSUED 328 AM CST WED FEB 10 2010/

DISCUSSION...
SURFACE HIGH PRESSURE WILL MOVE OVER MINNESOTA TODAY...ALONG WITH
DRIER AIR.

NORTH TO NORTHEAST LOW LEVEL FLOW OVER LAKE SUPERIOR TODAY WILL
GRADUALLY BACK. STABILITY REMAINS MARGINAL FOR SIGNIFICANT LAKE
EFFECT SNOW SHOWERS...AND KIWD AND KASX BOTH HAVE HAD VSBYS OF
10SM FOR THE PAST FEW HOURS. THE NORTHEAST LOW LEVEL FLOW IS NOT
VERY SUPPORTIVE FOR LES AT KIWD...SO THERE COULD BE SNOW FALLING
BETWEEN KASX/KIWD. WE KEPT CHANCE/LIKELY POPS FOR PORTIONS OF
ASHLAND AND IRON COUNTIES THIS MORNING...THEN REDUCED THEM THIS
AFTERNOON AS COLUMN DRIES. ADDITIONAL SNOWFALL TODAY SHOULD BE
LESS THAN AN INCH.

TONIGHT...THE HIGH AT THE SURFACE WILL CONTINUE EAST AND THERE
WILL BE LITTLE PRESSURE GRADIENT OVER THE CWA ALLOWING FOR LIGHT
WINDS. THERE MAY BE SOME CLOUDS ACROSS A PORTION OF NORTHWEST
WISCONSIN DUE TO NORTHERLY WINDS...AND PERHAPS SOME HIGH CLOUD
DRIFTING THROUGH THE REST OF THE CWA...BUT IT SHOULD BE A GOOD
RADIATIONAL COOLING NIGHT.

A SHORTWAVE WILL MOVE THROUGH NORTH DAKOTA ON THURSDAY...WITH WEAK
LOW PRESSURE AT THE SURFACE. THESE FEATURES WILL ONLY CAUSE AN
INCREASE IN CLOUDS THROUGH THE DAY THURSDAY...PARTICULARLY OVER
WESTERN AREAS.

EXTENDED...THUR NIGHT THRU SUNDAY...MDLS IN GOOD AGREEMENT THAT A
MID LVL HIGH WILL REMAIN FIXED OVER HUDSON BAY INTO EARLY SATURDAY.
THIS WILL DEFLECT ANOTHER SHORTWAVE IN THE WESTERLIES SOUTH FROM
SASK INTO THE NRN PLAINS. GFS IS FARTHEST EAST WITH MID LVL CTR WITH
EC/CMC FARTHER WEST. BY 12Z SUN BOT EC/GFS AGREE ON STRENGTH AND
POSITION OF MID LVL LOW OVER IA. AT SFC...HIGH PRESSURE WILL RIDGE
SOUTH FROM ONTARIO WITH LIMITED OPPORTUNITY FROM MUCH SFC
CONVERGENCE THIS PERIOD. AS INITIAL MID LVL FEATURE MOVES INTO
DAKOTAS A PERIOD OF WEAK ISENTROPIC LIFT IS PUSHED INTO WRN EDGE OF
CWA AND THAT IS WHERE ANY DECENT CHANCE OF POPS EXISTS THUR NIGHT
INTO EARLY SATURDAY. OTHERWISE LIGHT FLOW OFF SUPERIOR SHOULD ALLOW
SOME FLURRIES ALONG THE SOUTH SHORE. WARMING TREND SUN/MON WITH 85H
TEMP ANOMALIES FCST BY BOTH EC/GFS.

AVIATION.../06Z TAF ISSUANCE/
HIGH PRESSURE WILL BRING VFR CONDITIONS TO ALL OF THE MN TAF SITES
THROUGH THE MORNING AND INTO THE AFTERNOON. FOR KHYR...CLOUDS
STREAMING OFF LAKE SUPERIOR KEEPING MVFR CONDITIONS EARLY
TODAY..LATEST NAM12 COND PRESS DEFICITS SUGGEST IT MAY BREAK AND
REFORM AGAIN LATER THIS MORNING. WILL REASSESS ON NEXT SET OF TAF
ISSUANCE.

&&

.POINT TEMPS/POPS...
DLH  21  -4  19   3 /   0   0  10  10
INL  18 -16  21   2 /   0   0  10  10
BRD  19 -13  19   8 /   0   0  10  20
HYR  22 -13  22  -4 /   0  10  10  10
ASX  22  -6  23  -1 /   0  10  10  10

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&

$$

GSF/BERDES