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000
FXUS63 KDLH 301738
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1238 PM CDT WED JUL 30 2014

.UPDATE...
ISSUED AT 910 AM CDT WED JUL 30 2014

MORNING UPDATE TO EXTEND THE AREA OF FOG/STRATUS OVER NORTHERN
WISCONSIN AND THE SOUTH SHORE OF LAKE SUPERIOR FOR A FEW MORE
HOURS. ALSO ADDED A FEW MORNING SPRINKLES TO THE IRON RAGE AS
LATEST VISIBLE SATELLITE IS SHOWING CUMULUS DEVELOPMENT WITH
RADAR DEPICTING A FEW SMALL HIGH BASED SPRINKLES/VIRGA IN THE
COOK/CRANE LAKE AREA...TRACKING SOUTH.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 335 AM CDT WED JUL 30 2014

MAIN CONCERNS IN THE SHORT TERM REMAINED FOCUSED AROUND THE AREAS
OF FOG THIS MORNING...LOCALLY DENSE AT TIMES...AND THE POTENTIAL
FOR SCATTERED RAIN SHOWERS AND ISOLATED THUNDERSTORMS THIS
AFTERNOON AND INTO THE EVENING ACROSS THE ERN HALF OF THE FORECAST
AREA.

THE COOL AND ACTIVE NRLY PATTERN WILL PERSIST TODAY AND TONIGHT
AS A DEEP UPPER TROUGH OVER ERN CANADA CONTINUES TO ROTATE VERY
SLOWLY EWD. SHOWERS AND STORMS TRIGGERED YESTERDAY
AFTERNOON/EVENING HAVE SINCE DIMINISHED AND MOVED OUT OF THE AREA.
HOWEVER...THE RAIN HAS LEFTOVER A VERY MOIST NEAR-SFC LAYER THAT
IS COMBINING WITH CLEARING SKIES...COOLING TEMPERATURES AND LIGHT
WINDS TO PRODUCE AREAS OF FOG THIS MORNING. VISIBILITIES WILL DROP
TO 1/2 TO 1/4 MILE AT TIMES. A DENSE FOG ADVISORY MAY BE NEEDED
FOR A FEW HOURS...BUT WILL HOLD OFF AT THIS TIME AND MONITOR THE
TRENDS IN THE NEXT COUPLE HOURS. CONDITIONS WILL CONTINUE TO
REMAIN FAVORABLE FOR FOG THROUGH THE MID MORNING...BEFORE THE HIGH
SUN ANGLE AND DRY AIR ALOFT BEGIN TO MIX THE BL ENOUGH TO SCOUR
THE FOG AND LOW CLOUDS OUT.

MUCH OF THE NORTHLAND WILL BE CAUGHT BETWEEN THE ACTIVE...COOL
CYCLONIC FLOW TO THE EAST AND A BUILDING DRY RIDGE OF HIGH
PRESSURE TO THE WEST. PLENTY OF SUN THROUGH THE LATE MORNING AND
EARLY AFTERNOON WILL ALLOW TEMPERATURES TO WARM INTO THE MID TO
UPPER 70S...WITH A FEW LOWER 80S POSSIBLE. THE RISE IN
TEMPERATURES AND DESTABILIZING BNDY LYR WILL COMBINE WITH AN
EMBEDDED S/W DROPPING IN FROM THE NORTH TO PRODUCE MID- LATE
AFTERNOON CONVECTION FROM THE ARROWHEAD SWD THROUGH THE TWIN PORTS
AND INTO NW WI. ML CAPE VALUES INCREASE TO AROUND 500 J/KG AND
DEEP LAYER SHEAR REMAINS FAVORABLE FOR ANOTHER ROUND OF POSSIBLY
STRONG T-STORMS WITH SMALL HAIL AND STRONG WINDS. CANNOT RULE OUT
AN ISOLATED SEVERE STORM AS WELL.

CONVECTION WILL BE LARGELY FORCED BY THE DIURNAL HEATING TODAY...SO
EXPECT MUCH OF THE SHOWERS AND STORMS TO DIMINISH IN COVERAGE AND
INTENSITY AFTER SUNSET WITH SKIES CLEARING OUT AFTER MIDNIGHT.
TEMPERATURES TONIGHT WILL FALL INTO THE UPPER 40S AND LOWER 50S
AGAIN.

.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 335 AM CDT WED JUL 30 2014

LOOKING AT THE BIG PICTURE....THE UPPER LOW OVER JAMES BAY CANADA
SLIPS SOUTH AND THEN EAST INTO THE WEEKEND...FOLLOWED BY UPPER LEVEL
RIDGING OVER THE WESTERN GREAT LAKES REGION.

THIS UPPER LOW WILL CONTINUE THE TREND OF BRING S/WVS SOUTH INTO NRN
MN/WI...AND SETTING OFF AFTERNOON STORMS THROUGH THURSDAY. LONG
RANGE MODELS SUGGEST THE LOW FINALLY BEGINS TO FILL AND VERY SLOWLY
PUSH EAST FRIDAY...WITH A BRIEF PERIOD OF RIDGING SATURDAY AND
SATURDAY NIGHT. HOWEVER THIS WILL BE SHORT-LIVED AS A SERIES OF
S/WVS RIDE OVER THE RIDGE.  ON SUNDAY BOTH THE GFS AND ECMWF POINT
AT A LOW PRESSURE DEVELOPING IN THE HIGH PLAIN AND SETTING UP A WARM
FRONT OVER CENTRAL MN AND NRN WI...THIS COULD MEAN A CLOUDY AND WET
BEGINNING OF THE WEEK OVER THE FA. THE GFS KEEPS THE FRONT NEARLY
STATIONARY WHILE THE ECMWF IS MORE PROGRESSIVE WITH THIS SYSTEM.  AT
ANY RATE...THERE WILL BE CHANCES OF SHOWERS AND THUNDERSTORMS
THROUGHOUT NEXT WEEK.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1237 PM CDT WED JUL 30 2014

SCATTERED SHOWERS/STORMS WILL DEVELOP THIS AFTERNOON ACROSS
CENTRAL AND EASTERN PORTIONS OF THE NORTHLAND. THE STRONGER STORMS
WILL PRODUCE A BRIEF PERIOD OF MVFR OR POSSIBLY IFR CONDITIONS.

THE SHOWERS/STORMS WILL END LATER THIS EVENING AND SKIES WILL
BECOME CLEAR TO PARTLY CLOUDY. SOME FOG WILL ONCE AGAIN BE
POSSIBLE LATER TONIGHT AS WINDS GO LIGHT.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  78  51  79  54 /  30  20  20  10
INL  80  49  79  51 /  20  10  20  10
BRD  80  54  82  56 /  10  10  20  10
HYR  77  50  81  53 /  30  30  30  20
ASX  77  48  74  52 /  40  20  20  10

&&

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

$$

UPDATE...GRANING
SHORT TERM...BJT
LONG TERM...CLC
AVIATION...MELDE