Area Forecast Discussion Issued by NWS Duluth, MN
000
FXUS63 KDLH 250827
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
327 AM CDT SAT MAY 25 2013
.SHORT TERM...TODAY THROUGH SUNDAY...
AXIS OF WEAK WARM ADVECTION AND FRONTOGENESIS MAXED OUT IN THE
700-600MB LAYER CONTINUES TO TRANSLATE SLOWLY EASTWARD ACROSS
EASTERN MINNESOTA EARLY THIS MORNING WHILE SLOWLY WEAKENING. NW-SE
ORIENTED BAND OF SHOWERS HAS SLOWLY DIMINISHED IN BOTH COVERAGE
AND INTENSITY OVER THE PAST COUPLE OF HOURS..AND SHOULD CONTINUE
TO DO SO THROUGH MID MORNING TODAY. HOWEVER..UNTIL LOW-MID LEVEL
FLOW BACKS AS IT STARTS TO FEEL THE INFLUENCE OF THE NEXT WAVE
MOVING FROM THE ROCKIES INTO THE NRN PLAINS THERE WILL BE AT LEAST
SOME MODEST FORCING FOR ASCENT..AND A FEW SHOWERS COULD PERSIST
INTO LATE MORNING.
BY THIS AFTERNOON..MAIN THREAT FOR ADDITIONAL SHOWERS/TSTORMS IS
EXPECTED TO CONSOLIDATE TO AREAS MOSTLY SOUTH AND WEST OF THE
DULUTH CWA IN CLOSER PROXIMITY TO LOW LEVEL BAROCLINIC ZONE FROM
THE DAKOTAS INTO THE MID MISSOURI VALLEY. AS A RESULT..WE HAVE
CONTINUED THE PREVIOUS TREND OF A DRY FORECAST FOR THIS AFTERNOON
IN MOST AREAS AS EAST/SOUTHEAST LOW LEVEL FLOW BRINGS A FLUX OF
DRIER AIR INTO THE REGION. THE FAR SOUTHWEST CWA WILL REMAIN CLOSE
ENOUGH TO THE LOW LEVEL THERMAL/MOISTURE GRADIENT TO WARRANT AT
LEAST A MENTION OF A FEW SHOWERS TONIGHT. CHANCES FOR SHOWERS THEN
EXPAND A BIT FARTHER EASTWARD ON SUNDAY AS NEXT WAVE BRUSHES
NORTHEASTWARD..ALONG WITH SOME CONTRIBUTION FROM ENHANCED
WARM/MOIST ADVECTION BY THE LLJ LATE SAT NIGHT AND SUNDAY MORNING.
EASTERLY BOUNDARY LAYER FLOW WILL ALSO KEEP AREAS NEAR LAKE
SUPERIOR COOLER TODAY AND SUNDAY..ALONG WITH LOCALLY GUSTY WINDS
IN SOME OF THE FAVORED LOCATIONS NEAR THE TWIN PORTS AND ASHLAND.
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY NIGHT...
A PERIOD OF ACTIVE WEATHER WILL DEVELOP THIS WEEK WITH MULTIPLE
DISTURBANCES MOVING ACROSS THE UPPER MIDWEST...PRODUCING RAIN
SHOWERS AND THUNDERSTORMS MONDAY THROUGH SATURDAY. UPPER LEVEL
RIDGE AXIS ACROSS THE REGION LATE THIS WEEKEND WILL SHIFT EWD ON
MONDAY AS A 500MB S/W PUSHES INTO THE RIDGE ACROSS THE NRN PLAINS
ON THE LEADING EDGE OF A LONG WAVE TROUGH OVER THE WRN CONUS. THIS
S/W IS EXPECTED TO HAVE AN ASSOCIATED SFC INVERTED TROUGH/WARM
FRONT LIFT NWD THROUGH CNTRL MN ON MONDAY. RAIN SHOWER CHANCES
WILL INCREASE DURING THE DAY MONDAY...ALONG WITH A SLIGHT CHC OF
T-STORMS. A LLJ WILL DEVELOP MON NIGHT/TUE MORNING AND USHER IN A
MOIST UNSTABLE AIR MASS ACROSS THE REGION. THE INTERACTION OF THIS
S/W AND INCREASED INSTABILITY/MOISTURE WILL ALLOW FOR THE
POTENTIAL OF MDT/HVY RAIN SHOWERS AND EVEN A FEW STRONG STORMS
THROUGH TUE MORNING. THE ACTIVE PATTERN CONTINUES THROUGH THE
MIDDLE AND LATTER PART OF THE WEEK AS THE LONG WAVE TROUGH OVER
THE WEST TRANSITIONS EASTWARD AND CONTINUES TO DRAW UP A ROBUST
AMT OF WARM MOIST AIR FROM THE SOUTH AND PRODUCES RAIN SHOWERS AND
SCATTERED T-STORMS ACROSS THE NORTHLAND INTO THE EARLY PART OF THE
WEEKEND. THERE ARE NOTABLE DIFFERENCES IN THE SYNOPTIC PATTERNS OF
THE ECMWF AND GFS DURING THIS WEEK...WHICH LEAD TO UNRESOLVABLE
CONVECTIVE MODES. AT THIS TIME...WILL CONTINUE WITH HIGH CHC
POPS...LOW LIKELY POPS. IT WILL BE DIFFICULT TO NAIL DOWN SPECIFIC
TIMES/LOCATIONS OF THE BEST/HEAVIEST PRECIP AND ANY T-STORM
CHANCES UNTIL WELL INTO THE WEEK.
TEMPERATURES WILL CONTINUE ON THE WARMING TREND THROUGH THE WEEK
WITH HIGHS ON MONDAY IN THE 60S...AND OVERNIGHT LOWS IN THE 40S. BY
WEDNESDAY...HIGHS WILL BE TOPPING OUT IN THE 70S AND LOWER
80S...WITH NIGHT TIME LOWS IN THE 50S AND 60S.
&&
.AVIATION...06Z TAF ISSUANCE...
VFR CONDITIONS PREVAILED ACROSS THE NORTHLAND LATE THIS EVENING.
AN AREA OF SHOWERS STRETCHED FROM NORTHWEST MINNESOTA INTO
SOUTHEAST MINNESOTA. AN AREA OF MID LEVEL FGEN WAS HELPING TO
DRIVE THESE SHOWERS...AND THIS MOVES EAST THEN DIMINISHES
OVERNIGHT. MVFR CONDITIONS WILL BE POSSIBLE IN THE HEAVIER
SHOWERS...BUT THE OVERALL CHANCE OF THAT IS LOW AND MOST LIKELY
TOWARD KBRD. AN AREA OF MVFR CEILINGS EXISTS OVER PORTIONS OF
CENTRAL NEBRASKA LATE THIS EVENING...AND THE RAP SHOWS THOSE
MOVING QUICKLY NORTH INTO SOUTHWEST MINNESOTA TONIGHT BUT DOES NOT
BRING THEM INTO KBRD ON SATURDAY. WE`LL HAVE TO MONITOR THE
PROGRESSION OF THESE CLOUDS...AS WE WENT VFR FOR PREVAILING
CONDITIONS AT KBRD THROUGH THE PERIOD.
&&
.POINT TEMPS/POPS...
DLH 57 42 60 45 / 20 10 10 10
INL 64 44 68 47 / 10 10 10 20
BRD 61 46 62 50 / 40 20 30 40
HYR 63 42 67 47 / 20 10 10 20
ASX 60 40 61 43 / 10 0 0 0
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...MILLER
LONG TERM....TENTINGER
AVIATION...MELDE