Area Forecast Discussion


448 
FXUS63 KDLH 130913
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
413 AM CDT TUE AUG 13 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY...
A NEGATIVELY TILTED LONG WAVE TROUGH OVER THE ERN GREAT LAKES WILL 
KEEP THE NORTHLAND UNDER AN UPPER LVL NW FLOW TODAY. ALTHOUGH 
PROFILES SHOW THE AIR MASS IS LACKING MOISTURE WITH A SFC RIDGE 
APPROACHING THE FROM THE WEST...THE SEASONABLY COOL H85 TEMPS IN THE 
SINGLE DIGITS WILL ALLOW FOR AFTERNOON CU DEVELOPMENT AND A POSSIBLE 
SPRINKLE/LIGHT SHOWERS OVER THE FAR ERN ZONES. HAVE CARRIED A 20 POP 
FOR MUCH OF TODAY ACROSS THE MN ARROWHEAD/NRN WISC ZONES WHERE 
INSTABILITY IS THE GREATEST AND A VERY SHALLOW SATURATED LAYER 
AROUND H80 MAY BE ENOUGH TO SUPPORT A SHOWER OR TWO.
CONDITIONS TONIGHT WILL BE FAVORABLE FOR STRONG RADIATIONAL COOLING 
AS SFC RIDGING SETTLES OVERHEAD. HAVE LOWERED OVERNIGHT TEMPS A FEW 
DEGREES TOWARDS THE LATEST MAV/MEX GUIDANCE WHICH ARE SUGGESTING MIN 
TEMPS IN THE MIDDLE 30S TO LOW 40S. THE LAV/MET/ECM ARE RUNNING 
SLIGHTLY WARMER...BRINGING MOST AREAS DOWN INTO THE LOW TO MIDDLE 
40S. 
WEAK MID LEVEL WARM AIR ADVECTION RETURNS WEDNESDAY WITH SLIGHTLY 
WARMER TEMPERATURES AND DRY CONDITIONS.    
EXTENDED...WEDNESDAY THROUGH MONDAY...
THE REMAINDER OF THE WEEK WILL BE DOMINATED BY A LARGE SFC HIGH 
STRETCHING FROM SRN MANITOBA/ONTARIO TO THE OHIO VALLEY. A NW MID 
LVL FLOW WILL PROVIDE SYNOPTIC SCALE SUBSIDENCE. AS A RESULT A 
PERIOD OF QUIET WX IS EXPECTED ACROSS THE CWA. CHANGES OCCUR DURING 
THE WEEKEND AS THE MID LVL PATTERN SHIFTS TO A DEVELOPING MID LVL 
RIDGE OVERHEAD AND DOWNSTREAM TROUGHING IN THE SERN CONUS. AN 
INCREASINGLY STRONGER WARM ADVECTION REGIME WILL DEVELOP FROM WEST 
TO EAST SAT/SUN. ANTICYLONICALLY CURVED FLOW IN THE BDRY LYR 
COMBINED WITH RIDGING ALOFT MAKES ANY ORGANIZED ASCENT DOUBTFUL. 
HOWEVER LATEST FCST INSTABILITY AXIS AT 85H SUGGEST A FEW STRAY 
SHOWERS OR STORMS MAY ERUPT SATURDAY BEFORE MORE SIGNIFICANT CAPPING 
ARRIVES SUNDAY. MOST PROBABLE CHC OF PRECIP ARRIVES MONDAY AS A 
FRONTAL SYSTEM IS CARRIED INTO THE CWA BY STRENGTHENING WESTERLY 
FLOW ALOFT. TEMPS WILL AVERAGE NEAR CLIMO WED THROUGH FRIDAY AND 
THEN A WARMING TREND IS EXPECTED FOR THE WEEKEND AS UPPER HEIGHTS 
BUILD AND 85H TEMP VALUES INCREASE TO 15C TO 18C. 
&&
.AVIATION...06Z TAF ISSUANCE...
VERY WEAK DISTURBANCE WILL DROP SOUTHWARD ACROSS THE MINNESOTA 
ARROWHEAD AND NORTHWEST WISCONSIN TONIGHT AND TUESDAY MORNING. 
HOWEVER...BROKEN VFR CEILINGS AND LIGHT SHOWERS SHOULD STAY TO AREAS 
JUST NORTHEAST OF THE KHIB/KDLH/KHYR TERMINALS. CLEAR SKIES AND 
LIGHT WINDS MAY ALSO RESULT IN SOME FOG FORMATION 08-13Z 
TUESDAY..MOST NOTABLE AT THE FAVORED LOCATIONS OF KHYR/KHIB. 
SCATTERED CUMULUS EXPECTED TO DEVELOP 14-16Z TUE..WITH PERHAPS A 
BRIEF PERIOD OF BROKEN VFR CEILINGS FOR A COUPLE HOURS.  CLOUD BASE 
SHOULD LIFT THRU THE DAY AND BECOME SCATTERED BEFORE SKIES CLEAR 
00-02Z WED. WINDS THRU THE PERIOD SHOULD BE LIGHT/VARIABLE OR 
NORTHERLY AROUND 10KT OR LESS TUE AFTERNOON.
&&
.POINT TEMPS/POPS...
DLH  73  46  73  49 /  10   0   0   0 
INL  71  36  72  44 /   0   0   0   0 
BRD  76  46  77  50 /   0   0   0   0 
HYR  72  40  74  46 /  10   0   0   0 
ASX  70  40  71  50 /  20   0   0   0 
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...GRANING
LONG TERM....CANNON