013 FXUS63 KFGF 180441 AFDFGF AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 1141 PM CDT MON JUN 17 2013 .UPDATE... ISSUED AT 1140 PM CDT MON JUN 17 2013 UPDATED FOR AVIATION DISCUSSION ONLY. UPDATE ISSUED AT 925 PM CDT MON JUN 17 2013 CURRENT RADAR SHOWING CONVECTION MAINLY SOUTH OF I 94 CORRIDOR ALTHOUGH WE ARE SEEING SOME NEW DEVELOPMENT ON THE ND SIDE OF THE CENTRAL VALLEY. THINK WITH LOSS OF SOLAR ANY NEW DEVELOPMENT WILL BE SHORT LIVED AND MAIN ACTIVITY WILL BE ACROSS SOUTHEASTERN ND JUST AHEAD OF VORT MAX AND IN A WEAKENING RIBBON OF 500 TO 1000 J/KG CAPES. IMPULSE SHOULD DROP INTO NORTHEASTERN SD OVER NEXT HOUR AND EXPECT END OF ACTIVITY BY 04Z. WILL GO AHEAD AND ADJUST POPS FOR THIS. DEWPOINTS IN THE NORTHEAST NOW INTO THE UPPER 40S SO HAVE LOWERED TEMPS A FEW DEG IN THIS AREA...BUT DO NOT SEE THE DRIER LOW 40S/UPPER 30S OVER SWRN ONTARIO IMPACTING MY NORTHEASTERN ZONES SO WILL KEEP LOWS IN THIS REGION IN THE 45 TO 50 RANGE. NEEDED TO RAISE HOURLY TEMPS ACROSS SOUTHERN VALLEY FOR THE NEXT THREE TO FOUR HOURS...BUT TEMPS ELSEWHERE LOOK GOOD. OTHER THAN MINOR CLOUD TREND CHANGES...NOT OTHER CHANGES EXPECTED WITH THIS UPDATE. UPDATE ISSUED AT 633 PM CDT MON JUN 17 2013 MODERATE CAPE IN WESTERN ZONES...AND SOUTHEASTWARD MOVEMENT OF H500 LOW WILL KEEP SOME RAIN SHOWERS AND AN ISOLATED TSTMS ACROSS MY SOUTHWEST THROUGH MID EVENING. DO HAVE A COUPLE OF TSTMS ON RADAR AT CURRENT TIME...ONE OVER WESTERN CASS COUNTY AND THE OTHER IN CENTRAL POLK. CONVECTION SHOULD DISSIPATE OVER NEXT COUPLE OF HOURS BUT SHOWERS COULD HOLD ON IN THE VALLEY CITY AREA AS UPPER LOW APPROACHES...BUT THINK ALL ACTIVITY WILL END BY MIDNIGHT. WILL FINE TUNE POPS FOR 7 PM CDT UPDATE WITH NO SIG CHANGES TO TEMPS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 310 PM CDT MON JUN 17 2013 CONCERNS FOR THE SHORT-TERM FORECAST INCLUDE DISSIPATING SHOWERS/ T-STORMS THIS EVENING AND TEMPERATURES OVERNIGHT. ALTHOUGH THERE EXIST MODEL VARIANCES WITH QPF OUTPUT...SYNOPTIC FEATURES ARE IN GOOD AGREEMENT AND WILL USE A BLENDED SOLUTION. 20 UTC RADAR SHOWS A SCATTERED LINE OF SHOWERS FROM NEAR CANDO TO PARK RAPIDS. EXPECT THIS ACTIVITY TO SAG SOUTHWARD LATE THIS AFTERNOON AND EVENING AS A WEAK UPPER LOW MOVES INTO WEST CENTRAL MN BY 06 UTC TONIGHT. A LIGHTNING STRIKE OR TWO IS POSSIBLE...BUT OVERALL VERTICAL EXTENT OF CU IS LIMITED...SO NOT EXPECTING MUCH IN THE WAY OF THUNDERSTORMS. MAJORITY OF CU/SHOWERS WILL DISSIPATE AFTER SUNSET WITH SURFACE HIGH PRESSURE BUILDING FROM THE WEST. WINDS WILL BECOME LIGHT AND VARIABLE BY DAYBREAK TUESDAY MORNING AND WITH MOSTLY CLEAR SKIES...NIGHTTIME LOWS WILL DROP INTO THE UPPER 40S TO MID 50S. TUESDAY WILL BE MOSTLY SUNNY AND DRY AS THE SURFACE HIGH PRESSURE DRIFTS INTO CENTRAL WI. SOUTHERLY RETURN FLOW WILL DEVELOP IN ITS WAKE...RESULTING IN LIGHT SOUTHERLY SURFACE WIND FROM 5 TO 10 MPH. SOUNDINGS SHOW THE BOUNDARY LAYER WARMS 1 TO 4 C BY TUESDAY AFTERNOON SO EXPECT HIGHS IN THE MID TO UPPER 70S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 310 PM CDT MON JUN 17 2013 A SHORT-WAVE RIDGE ALOFT WILL MOVE ACROSS THE NORTHERN PLAINS WEDNESDAY AND THURSDAY. GREATEST INSTABILITY AND FORCING FOR WEDNESDAY IS WEST OF THE FORECAST AREA...BUT WILL KEEP LOW-END CHANCE POPS GOING DUE TO WEAK MID-LEVEL WARM AIR ADVECTION/ ISENTROPIC LIFT AND THE POSSIBILITY OF A ROGUE SHORT-WAVE RIPPLE MOVING THROUGH THE RIDGE AXIS. SHOWER AND THUNDERSTORM CHANCES INCREASE THURSDAY AS FLOW ALOFT SHIFTS TO THE SOUTHWEST AND THE PRIMARY INSTABILITY AXIS MOVES INTO THE CENTRAL/EASTERN DAKOTAS. WITH ADDITIONAL LOW-MID LEVEL WARMING...TEMPERATURES WILL REACH INTO THE LOWER 80S MOST PLACES BOTH DAYS WITH MORNING LOWS FROM THE UPPER 50S INTO THE 60S. THU NIGHT THROUGH MONDAY...ACTIVE CONVECTIVE PATTERN SETTING UP FOR THE LONG RANGE PERIOD. UPPER LOW OVER PAC NW TO REMAIN FAIRLY STATIONARY UNTIL THE WEEKEND WHEN IT BEGINS TO PROPAGATE EAST. THIS WILL KEEP FA IN AN EXTENDED PERIOD OF SW MID LEVEL FLOW. WITH PERSISTENT SOUTHERLY FLOW WILL SEE SIGNIFICANT MOISTURE FLUX INTO FA RESULTING IN INCREASING PRECIPITABLE H2O VALUES AND DEWPOINTS CLIMBING INTO THE 60S MOST AREAS. AS A RESULT THERE WILL BE PLENTY OF INSTABILITY AND CAPE AVAILABLE. MAIN QUESTION WILL BE WHERE LOW LEVEL BOUNDARIES/LOW LEVEL FORCING SETS UP AS BROAD AREA OF LOW PRESSURE WILL AFFECT THE FA THROUGH THE PERIOD. MODELS CLOSE WITH MAIN FEATURES HOWEVER DIFFER ON LOCATION OF LOW LEVEL BOUNDARIES. FOR THIS TOUGH TO PIN POINT WHERE FAVORED AREAS FOR CONVECTION WILL BE. PROBABLY BE SEEING QUITE A BIT OF CLOUD COVER THROUGH THE PERIOD WITH TEMPERATURES CLOSE TO SEASONAL AVERAGES AND MILD OVERNIGHT MINIMUMS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1140 PM CDT MON JUN 17 2013 VFR CONDS TONIGHT AND TOMORROW. MID LVL CIGS ASSOCIATED WITH DISSIPATING SHOWERS WEST OF FAR WILL ERODE BY 06Z. SHOULD SEE DECREASING CLOUDS OVERNIGHT WITH WINDS SHIFTING TO THE SOUTHEAST. LIGHT SOUTHERLY FLOW DRG THE DAY WED WITH POTENTIAL FOR SOME VFR CIGS DROPPING INTO NERN ND TOMORROW AFTN...BUT WILL LIKELY REMAIN NORTH OF DVL-GFK-TVF AREA. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...SPEICHER SHORT TERM...ROGERS LONG TERM...ROGERS/VOELKER AVIATION...SPEICHER