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000
FXUS63 KDLH 140905
AFDDLH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
405 AM CDT FRI JUN 14 2013

.SHORT TERM...

TODAY THROUGH SATURDAY AFTERNOON...

MAIN CONCERNS IN THE SHORT TERM ARE FOCUSED AROUND THE INCOMING
SFC TROUGH EXPECTED TO BRING SHOWERS AND THUNDERSTORMS TO THE
NORTHLAND LATER TODAY AND THROUGH THE OVERNIGHT HOURS. THERE IS A
SMALL CHANCE THAT A FEW OF THESE STORMS COULD APPROACH SEVERE
LEVELS TONIGHT...WITH HAIL AND STRONG WINDS BEING THE MAIN
THREATS. OTHERWISE...STORMS SHOULD REMAIN WEAK WITH OCCASIONAL
LIGHTNING AND BRIEF HVY RAIN BEING THE MAIN THEME.

SURFACE RIDGE AXIS REMAINS SITUATED FROM NRN ONTARIO SWD INTO WI
AND IL THIS MORNING WITH THE UPPER RIDGE SLIGHTLY TO THE WEST
ACROSS MN. WEAK CONVECTION HAS BEEN ONGOING ACROSS SWRN/SRN MN
THIS MORNING...ALONG A WEAKLY DEFINED SFC TROUGH AND ON THE NRN
EDGE OF A DEVELOPING LLJ ACROSS THE CENTRAL PLAINS WITH ENOUGH
700MB F-GEN TO TRIGGER THESE T-STORMS. THIS CONVECTION WILL
ATTEMPT TO SLIDE EWD INTO THE SWRN SECTIONS OF THE FORECAST AREA
THIS MORNING...BUT WILL BE MET WITH A VERY STABLE AIR MASS THAT
WILL ACT TO SUPPRESS MUCH OF THIS ACTIVITY. CAN NOT RULE OUT A FEW
LIGHT RAIN SHOWERS AROUND THE BRD LAKES AREA THIS MORNING...SO
LEFT IN LOW POPS AROUND THIS AREA FROM 12-18Z.

THERE ARE NOTABLE DIFFERENCES IN THE TIMING OF THE PRECIP AND
CONVECTION INTO THE AREA FROM THE W/SW...WITH THE ECMWF
PERSISTENTLY BRINGING A BAND OF QPF INTO A GOOD PORTION OF THE
AREA BEFORE 18Z...AND ALL OTHER MODELS HOLDING OFF UNTIL CLOSER TO
00Z. THE FORECAST ATTEMPTS TO MAKE A COMPROMISE OF THESE
SOLUTIONS...WITH AN EMPHASIS ON DELAYING THE PROGRESSION OF THE
HIGHER POPS TO THE EAST AS IT BATTLES THE DRIER AIR OVER NE
MN/LAKE SUPERIOR.

THE STRONG PUSH OF SHOWERS AND STORMS WILL BE AFTER 00Z TONIGHT
AND BEFORE 12Z SATURDAY WITH THIS PERIOD BEING THE MOST FAVORABLE
FOR STRONG TO POSSIBLY A FEW LOW-END SEVERE STORMS. WILL LIKELY
SEE A GOOD SECTION OF THE NE MN DESTABILIZE IN THE BL AND BECOME
CONDUCIVE FOR T-STORM DEVELOPMENT. ML CAPE VALUES APPROACH 1000
J/KG AROUND BRD LATE THIS AFTERNOON WITH THIS INSTABILITY AXIS
SHIFTING EWD THROUGH THE EVENING AND OVERNIGHT. A 40KT LLJ IS
EXPECTED TO DEVELOP TONIGHT AND HELP ENHANCE THE MID-LEVEL
STRUCTURE OF THESE STORMS. HOWEVER...AS THE CONVECTION MOVES EWD
IT WILL ENCOUNTER A VERY STABLE NEAR-SFC LAYER AROUND LAKE
SUPERIOR AND ALLOW MOST OF THE STORMS TO BECOME ELEVATED. LATEST
GFS/NAM 850-500MB CAPE VALUES AROUND 06Z TONIGHT ARE 200-400 J/KG.
THE HEIGHT OF THE WBZ FOR MUCH OF THE REGION IS ABOVE 11K FT...SO
IT WILL BE DIFFICULT TO GENERATE LARGE HAIL...BUT NOT OUT OF THE
QUESTION TO SEE A LOT OF SMALL HAIL OR NEAR SVR SIZE HAIL.
RAINFALL AMTS WITH THIS SYSTEM ARE EXPECTED TO BE AROUND A QUARTER
TO HALF AN INCH...WITH VERY ISOLATED HIGHER AMTS IN THE STRONGER
CELLS.

AN AREA OF HIGH PRESSURE AT THE SFC BUILDS IN QUICKLY ON SATURDAY
AND ALLOWS CONDITIONS TO DRY OUT AND SKIES TO CLEAR OFF THROUGH
THE AFTERNOON.

TEMPERATURES TODAY WILL BE VERY SIMILAR TO PREVIOUS DAYS THIS WEEK
WITH HIGHS IN THE 70S AND LOWER 80S...WITH THE EXCEPTION BEING
AROUND THE PERIPHERY OF LAKE SUPERIOR...INCLUDING THE TWIN PORTS
WHERE A STIFF LAKE BREEZE WILL KEEP TEMPS IN THE 60S. A WIND SHIFT
TO THE WEST TOMORROW WILL BRING TEMPS BACK INTO THE 70S FOR MUCH
OF THE REGION.

.LONG TERM...

SATURDAY NIGHT THROUGH FRIDAY...

THE LONGER PERIOD BEGINS WITH SOME POSSIBLE LINGERING SHOWERS
SATURDAY EVENING IN NORTHWESTERN WI.

THE EXTENDED PERIOD THROUGH NEXT WEEK WILL BE AFFECTED BY A
ELONGATED UPPER TROF OVR SRN CANADA AND AN UPPER RIDGE THAT WILL
BUILD IN FROM THE WEST LATER IN THE PERIOD. A SERIES OF S/WVS WILL
DIG DOWN INTO THE REGION.  THE FIRST ONE WILL BE SUNDAY...WITH MOST
OF THE ENERGY AND LIFT OVR NRN MN. WITH THE PASSAGE OF THE UPPER
S/WV A RIDGE OF HIGH PRESSURE WILL SLOWLY WORK ITS WAY EAST...WITH
THE UPPER RIDGE AXIS SETTLING OVER THE NORTHLAND SOMETIME LATE IN
THE WEEK. BY MID TO LATE WEEK THE EXTENDED MODELS SHOW THEIR
DIFFERENCES WITH THE GFS MUCH FASTER IN BUILDING IN THE RIDGE AND
FORECASTING A LARGE PACIFIC LOW TO DEVELOP AND SLOWLY MOVE ACROSS
THE NORTHERN TIER STATES. THE ECMWF PLAYS OUT THE SAME
SCENARIO...ONLY MORE SLOWLY.

WHAT THIS MEANS FOR THE NORTHLAND IS AN INCREASING CHANCE OF
THUNDERSTORMS TOWARD LATE IN THE WEEK AND WEEKEND.
TEMPERATURES WILL BE ABOUT NORMAL...IN THE 70S...WITH INCREASING
TEMPS AND HUMIDITY LATE IN THE WEEK.

&&

.AVIATION...06Z TAFS...

VFR CONDITIONS AT ALL SITES THROUGH FRIDAY AFTERNOON. A FRONTAL
SYSTEM WILL APPROACH THE INL-BRD TAF SITES LATE FRIDAY AFTERNOON
LOWERING THE CIGS. RAIN SHOWERS WILL SPREAD INTO BRD BY 00Z AND INL
BY 03Z. MVFR CONDITIONS WILL BE POSSIBLE IN RAIN AT THOSE
LOCATIONS. THE PRECIPITATION WILL SPREAD EAST AND WILL AFFECT THE
DLH/HIB TAF SITES AFTER 06Z.

&&

.POINT TEMPS/POPS...
DLH  64  51  76  55 /  30  80  40  10
INL  74  55  76  50 /  40  80  30  10
BRD  74  61  77  57 /  60  70  10  10
HYR  74  57  76  56 /  30  80  40  10
ASX  64  52  75  53 /  10  80  40  20

&&

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

$$

SHORT TERM...TENTINGER
LONG TERM....CLC
AVIATION...STEWART