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000
FXUS63 KDLH 171746 AAA
AFDDLH

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE DULUTH MN
1246 PM CDT FRI MAY 17 2013

.AVIATION...18Z TAF ISSUANCE...
VFR CIGS THIS AFTERNOON WILL GRADUALLY LOWER LATE AFTERNOON/EARLY
EVENING WITH RAIN CHANCES INCREASING THROUGH THE EVENING. WILL
ALSO SEE THE POTENTIAL FOR VCTS TO DEVELOP FROM SOUTH TO NORTH
TONIGHT...WITH THE BEST CHANCE AFTER 12Z SAT MORNING. CIGS WILL
LOWER TO MVFR AT TIMES DURING AND AFTER RAIN SHOWERS. COULD ALSO
SEE REDUCED VSBYS IN LIGHT FOG.

&&

.PREV DISCUSSION... /ISSUED 705 AM CDT FRI MAY 17 2013/

AVIATION...12Z TAF ISSUANCE...
MAIN AREA OF RAIN/STORMS WILL REMAIN SOUTH OF CWA THIS MORNING HOWEVER
A GRADUAL MOISTENING OF THE ATMOSPHERE WILL OCCUR ACROSS THE
NORTHLAND TODAY. THIS PRESENTS AN OPPORTUNITY FOR VCSH AT
KBRD/KDLH/KHYR THIS MORNING...WITH CHANCES OF RAIN INCREASING FROM
LATE TODAY AND INTO THE OVERNIGHT. THUNDERSTORMS MAY OCCUR AT
KBRD/KDLH OVERNIGHT.

PREV DISCUSSION... /ISSUED 400 AM CDT FRI MAY 17 2013/

SHORT TERM...
A STRENGTHENING WARM FRONT WILL LIFT OVER MUCH OF THE UPPER MIDWEST
TODAY. THE FRONT WILL SPREAD RAIN ACROSS THE SRN HALF OF THE
FORECAST AREA TODAY...MAINLY DURING THE AFTERNOON HOURS. THERE IS
A MINIMAL THREAT FOR ISOLD THUNDER ACROSS THE FAR SRN ZONES TODAY.
STRONG HIGH PRESSURE ANCHORED OVER ONTARIO WILL PRODUCE AN
INCREASING PRESSURE GRADIENT AND GUSTY EAST WINDS TODAY AS THE
WARM FRONT APPROACHES THE REGION. HAVE INCREASED WINDS/GUSTS
TODAY/TONIGHT OVER LAKE SUPERIOR AND ACROSS THE SRN ZONES. THE
GUSTY ONSHORE FLOW WILL ALSO KEEP TEMPERATURES QUITE COOL NEAR
LAKE SUPERIOR TODAY WITH HIGHS IN THE 40S AND 50S. INLAND
TEMPERATURES WILL WARM GENERALLY INTO THE UPPER 60 TO AROUND 70.

THE WARM FRONT WILL CONTINUE TO PUSH NORTH OVER THE REGION THROUGH
THE NIGHT/SATURDAY...PRODUCING WIDESPREAD RAIN AND ISOLD THUNDER
ACROSS MUCH OF THE NORTHLAND. BEST CHC FOR THUNDER ARRIVES SAT
AFTERNOON.

EXTENDED...SATURDAY NIGHT THROUGH THURSDAY...

POWERFUL JET STREAM WILL PLUNGE SOUTHEASTWARD FROM CALIFORNIA INTO
WEST TEXAS AT THE BEGINNING OF THIS PERIOD. CYCLOGENESIS WILL TAKE
PLACE IN THE SRN PLAINS AND SFC LOW WILL TRACK SLOWLY NORTH TOWARDS
NRN PLAINS MONDAY. BY THAT TIME...A MAJOR BLOCKING PATTERN IS
ADVERTISED BY MED RANGE MDLS WITH PLAINS MID LVL LOW BECOMING WEDGED
BETWEEN MID LVL VORTEXES OVER PACNW AND ERN CANADA.  A RELATIVE MID
LVL RIDGE BUILDS OVER CTRL CANADA WHICH KEEPS PLAINS LOW IN A
HOLDING PATTERN INTO MIDWEEK. FINALLY...THURSDAY MDLS SUGGEST SYSTEM
WILL BECOME ABSORBED INTO LARGE EASTERN CIRCULATION.

IN TERMS OF SENSIBLE WEATHER A PROLONGED PERIOD OF WET WEATHER IS
EXPECTED ACROSS THE NORTHLAND. SATURDAY NIGHT AND SUNDAY SHOULD SEE
POPS FAVORED OVER NWRN CWA...THEN MN ZONES. AS SFC/MID LVL LOW PUSH
INTO ERN SODAK EARLY MONDAY MOISTURE TRANSPORT IS EXPECTED TO SPREAD
FARTHER EAST INT WISC ZONES. THERE ARE UNCERTAINTIES INVOLVING THE
PRESENCE OF THE LARGE SFC HIGH OVER CANADA. DRY LOW LVL AIR WILL
ADVECT INTO EASTERN PART OF THE REGION CONSISTENTLY AS PRESSURE
GRADIENT STRENGTHENS SUNDAY/MONDAY. THIS MAY MAKE IT TOUGH FOR
ORGANIZED PRECIP TO PUSH FARTHER EAST INITIALLY. MDL QPF IS QUITE
HIGH FROM SUNDAY INTO TUESDAY WITH GFS/EC/GEM INDICATING TOTALS OF
1-3" POSSIBLE ACROSS NORTHLAND. MAX TEMPS WILL FALL BELOW CLIMO
MON/TUES...POSSIBLY WEDNESDAY. THIS IS ESPECIALLY THE CASE NEAR THE
TWIN PORTS AS A STRONG WIND OFF LAKE SUPERIOR COMBINED WITH PRECIP
MAKES FOR A VERY UNPLEASANT REMINDER OF THE MID 30S WATER TEMPS.
SOME INDICATIONS THAT DEEP LAYER DRYING MAKE OCCUR FROM NORTH TO
SOUTH TUESDAY AFTERNOON AS LARGE SFC/MID LVL HIGH OVER CANADA BEGINS
TO PUSH SOUTHWARD. THE MOVEMENT OF THIS FEATURE IS OF LOWER
CONFIDENCE. TEMPS RETURN TO NEAR CLIO BY THUR AS MID LVL PATTERN
SHIFTS AND BECOMES MORE PROGRESSIVE.

&&

.POINT TEMPS/POPS...
DLH  41  61  50  66 /  60  60  40  70
INL  45  65  52  66 /  50  60  70  70
BRD  50  78  59  74 /  60  60  70  70
HYR  47  77  56  77 /  60  50  20  50
ASX  44  72  51  69 /  60  60  20  50

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CDT SATURDAY FOR LSZ143>146.

&&

$$

AVIATION...TENTINGER