Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/04/14


AREA FORECAST DISCUSSION
NWS ALBANY NY
748 PM EDT SAT MAY 3 2014 .SYNOPSIS... A PERSISTENT UPPER LEVEL TROUGH WILL BRING COOL AND UNSETTLED WEATHER THROUGH THE WEEKEND. GRADUAL IMPROVEMENT IN THE WEATHER AND MODERATING TEMPERATURES ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 745 PM EDT...SCATTERED SHOWERS MOVING ACROSS MAINLY THE EASTERN HALF OF THE AREA EARLY THIS EVENING...WITH A BRIEF BREAK ACROSS CENTRAL/WESTERN ZONES. HOWEVER...TWO MORE LINES OF SHOWERS WITH EMBEDDED ISOLATED THUNDER AND 30-40 MPH WIND GUSTS MOVING EASTWARD ACROSS CENTRAL AND WESTERN NY. BY THE TIME THESE SHOWERS MAKE IT EASTWARD INTO OUR AREA...LOSS OF DAYTIME WILL LIKELY RESULT IN LESS INSTABILITY. HOWEVER...00Z ALB SOUNDING REVEALS INVERTED-V SIGNATURE...WHICH COULD STILL RESULT IN SOME EVAPORATIVE DOWNDRAFTS WITH THE SHOWERS. ENOUGH LIGHTNING UPSTREAM TO CONTINUE MENTION OF ISOLATED THUNDER THROUGH THE EVENING HOURS. HIGHEST POPS WILL BE LATER THIS EVENING...AS THE POTENT UPPER LEVEL DISTURBANCE RESPONSIBLE FOR THE CONVECTIVE SHOWERS APPROACHES. HIGH RES MODELS SUCH AS THE HRRR AND LOCAL WRF SEEM TO HAVE A DECENT HANDLE ON THE CURRENT PRECIP PATTERN AND SUPPORT INCREASING POPS LATER THIS EVENING. WILL GRADUALLY DECREASE POPS OVERNIGHT...EXCEPT FOR ACROSS THE WESTERN ADIRONDACKS WHERE ADDITIONAL SHOWERS ARE EXPECTED TO DEVELOP OVERNIGHT ON THE SOUTHERN PERIPHERY OF THE MAIN UPPER LEVEL CIRCULATION. WINDS WILL SHIFT TO THE WEST AFTER MIDNIGHT AS THE SURFACE TROUGH ASSOCIATED WITH THE UPPER DISTURBANCE MOVES THROUGH. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... SUNDAY SHOULD BE A REPLAY OF SATURDAY IN TERMS OF CLOUDS/SHOWERS AND TSTM POSSIBILITY. SHOWERS WILL START OFF ISOLATED TO SCATTERED AT BEST EARLY IN THE DAY...BUT AS A COLD POOL ALOFT DRIFTS OVER THE REGION AND SOME SURFACE HEATING TAKES PLACE...SHOWER COVERAGE SHOULD INCREASE AND HAVE FORECAST POPS OF 40 TO 70 PERCENT AGAIN BY SUNDAY AFTERNOON...ALONG WITH ISOLATED TSTMS. HIGHS WILL BE IN THE UPPER 40S ACROSS THE ADIRONDACK ZONES...AND 50S TO LOWER 60S ELSEWHERE. IT WILL ALSO BE WINDY WITH WESTERLY WINDS AT 15 TO 25 MPH AND GUSTS OVER 35 MPH POSSIBLE. WITH NO SHORT WAVE TROF MOVING ACROSS THE REGION SUNDAY EVENING TO KEEP THE SHOWERS GOING WELL PAST SUNSET...EXPECT SHOWERS TO DECREASE MORE QUICKLY SUNDAY EVENING AS DIURNAL HEATING DECREASES...AND POPS ARE FORECAST TO DECREASE TO ONLY SLIGHT CHANCE ACROSS MUCH OF THE REGION...WITH CHANCE POPS OVER THE HIGHER TERRAIN. BY SUNRISE THE HUDSON VALLEY AND THE SOUTHEAST PART OF THE FORECAST AREA WILL BE DRY. LOWS SUNDAY NIGHT WILL BE IN THE MID 30S TO MID 40S. WITH SURFACE HIGH PRESSURE BUILDING IN AND THE COLD POOL ALOFT OFF TO OUR EAST...SHOWER ACTIVITY WILL CONTINUE TO DECREASE ON MONDAY WITH ONLY NORTHERN MOUNTAIN AREAS FORECAST TO HAVE A SLIGHT TO LOW CHANCE OF SHOWERS DURING THE AFTERNOON. HIGHS WILL BE IN THE 50S TO LOWER 60S. SKIES WILL BE MAINLY CLEAR ACROSS THE REGION AND WINDS WILL BECOME LIGHT AS A COOL CANADIAN AIRMASS SETTLES OVER THE REGION. TUESDAY MORNING WILL ALSO MARK THE START OF THE GROWING SEASON FOR THE HUDSON VALLEY...INCLUDING WASHINGTON COUNTY AND SOUTHERN LITCHFIELD COUNTY. LOW TEMPS IN THIS REGION WILL BE IN THE MID OR UPPER 30S AND FROST ADVISORIES MAY BE NEEDED IF IT APPEARS IT WILL GET ANY COLDER THAN THAT. ELSEWHERE LOWS WILL BE IN THE UPPER 20S TO MID 30S. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THE PERIOD STARTS OUT WITH DRY AND PLEASANT CONDITIONS EXPECTED FOR TUESDAY AND WEDNESDAY...WITH PLENTY OF SUNSHINE DUE TO HIGH PRESSURE GRADUALLY BUILDING INTO THE REGION. TEMPERATURES WILL ONLY BE SLIGHTLY BELOW NORMAL...WITH A DRY NORTHWEST BREEZE EACH DAY. WINDS COULD BE A BIT GUSTY ON TUESDAY...WITH LIGHTER WINDS ON WEDNESDAY AS THE HIGH DRIFTS DIRECTLY OVER OUR AREA. THE FORECAST BECOMES A BIT MORE UNCERTAIN FROM THURSDAY INTO THE WEEKEND...AS WE WILL BE POTENTIALLY DEALING WITH A SURFACE WARM FRONT APPROACHING IN RESPONSE TO UPPER LEVEL RIDGING ACROSS THE OHIO VALLEY AND GREAT LAKES REGION. MODELS INDICATING THE UPPER RIDGE AXIS TO REMAIN TO OUR WEST THROUGH FRIDAY...WHICH MAY HINDER THE NORTHWARD PROGRESS OF THE WARM FRONT...WITH THE CHANCE OF A FEW ROUNDS OF SHOWERS MOVING THROUGH. THIS WILL MAKE TEMPERATURE FORECAST TRICKY THURSDAY AND FRIDAY...AS COMPLETELY OVERCAST SKIES COULD LEAD TO COOLER READINGS BUT JUST A FEW BREAKS OF SUNSHINE WOULD ALLOW FOR MORE SIGNIFICANT WARMING. KEPT MAX TEMPS CLOSE TO NORMAL FOR NOW...ALTHOUGH OVERNIGHT LOWS MAY END UP MORE ON THE MILD SIDE DUE TO MOSTLY CLOUDY SKIES AND SCATTERED SHOWERS. UNSETTLED WEATHER COULD LINGER WELL INTO NEXT WEEKEND...AS ONE OR MORE SURFACE BOUNDARIES MAY PASS THROUGH. THE LATEST ECMWF INDICATING A POTENTIAL WAVE OF LOW PRESSURE DEVELOPING ALONG A STALLING BOUNDARY...WHICH WOULD RESULT IN PROLONGED CHANCES FOR RAINFALL WELL INTO THE WEEKEND. THE GFS IS MORE PROGRESSIVE...BUT THIS IS STILL A WEEK OUT SO THERE IS LOW CONFIDENCE FOR THIS TIME FRAME. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... UNSETTLED WEATHER WILL CONTINUE AS THE REGION WILL BE UNDER THE INFLUENCE OF AN UPPER LEVEL LOW. A DISTURBANCE WILL MOVE FROM WEST TO EAST ACROSS THE REGION LATE THIS EVENING...BRINGING NUMEROUS SHOWERS AND PERHAPS AN ISOLATED THUNDERSTORM TO THE TERMINALS. THE PROBABILITY OF THUNDER IS LOW SO OMITTED MENTION IN THE TAFS. HIGHEST CONFIDENCE FOR SHOWERS MOVING THROUGH WILL BE FROM AROUND 02Z-07Z ACROSS THE AREA. HAVE ACCOUNTED FOR THE SHOWERS WITH TEMPO GROUPS FOR MVFR CONDITIONS...ALTHOUGH BRIEF IFR WILL ALSO BE POSSIBLE WITHIN ANY HEAVIER SHOWERS. BRIEF STRONG WIND GUSTS AROUND 30 KT MAY ALSO BE POSSIBLE BUT PROBABILITY OF OCCURRING AT A SPECIFIC TERMINAL IS LOW. EXPECTING A BREAK IN THE SHOWER ACTIVITY LATE TONIGHT INTO SUNDAY MORNING...ALTHOUGH ADDITIONAL SHOWERS ARE EXPECTED TO DEVELOP BY SUNDAY AFTERNOON AS ANOTHER DISTURBANCE MOVES ACROSS THE AREA. WINDS WILL INITIALLY BE SOUTH-SOUTHWEST AROUND 5-10 KT TONIGHT...SHIFTING TO THE WEST AND INCREASING TO 8-15 KT WELL AFTER MIDNIGHT. WINDS ON SUNDAY WILL BECOME INCREASINGLY GUSTY FROM THE WEST AT 15-20 KT WITH GUSTS OF 25-30 KT EXPECTED WITH GOOD MIXING CONDITIONS DEVELOPING. OUTLOOK... SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY. CHANCE OF SHRA. MONDAY: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX. MONDAY NIGHT TO WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. && .FIRE WEATHER... COOL AND UNSETTLED CONDITIONS ARE FORECAST THROUGH THIS WEEKEND...AS A SERIES OF UPPER LEVEL DISTURBANCES APPROACH FROM THE GREAT LAKES REGION. EACH FEATURE WILL BRING AN INCREASED CHANCE FOR SHOWERS AND POSSIBLE THUNDERSTORMS...ESPECIALLY DURING THE AFTERNOON AND EVENING HOURS. && .HYDROLOGY... NO HYDROLOGIC PROBLEMS ARE EXPECTED DURING THE NEXT 5 DAYS. SCATTERED RAIN SHOWERS ARE FORECAST TO PRODUCE A TENTH TO A HALF INCH BASIN AVERAGE OF RAINFALL DURING THE NEXT 5 DAYS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...GJM NEAR TERM...GJM/JPV SHORT TERM...GJM LONG TERM...JPV AVIATION...JPV FIRE WEATHER...GJM/BGM HYDROLOGY...SND/GJM/BGM
AREA FORECAST DISCUSSION
NWS MIAMI FL
153 AM EDT FRI MAY 2 2014 .AVIATION... DRY AND VFR CONDITIONS WILL PREVAIL THIS MORNING. AFTER NOON...A FEW SHOWERS ARE POSSIBLE...WITH POPS RANGING FROM 20-30 PERCENT OVER BROWARD AND MIAMI-DADE TERMINALS TO AROUND 40 PERCENT KAPF AND KPBI...WHERE VCSH IN PLACE. BY LATE EVENING...ACTIVITY SHOULD WANE...ALTHOUGH ISOLATED SHOWERS CANT BE RULED OUT. WINDS WILL REMAIN SOUTHEAST...LIGHT THIS MORNING THEN 10-15 KTS DURING THE AFTERNOON...DIMINISHING AGAIN AFTER SUNSET. && .PREV DISCUSSION... /ISSUED 1001 PM EDT THU MAY 1 2014/ UPDATE...A FEW SHOWERS PERSIST AROUND LAKE OKEECHOBEE, BUT THEY ARE EXPECTED TO DISSIPATE THROUGH MIDNIGHT WITH TRANQUIL WEATHER PREVAILING OVERNIGHT. HRRR SHOWS ANY ADDITIONAL SHOWER DEVELOPMENT OVERNIGHT TAKING PLACE NORTH OF THE LAKE. MADE NO SIGNIFICANT CHANGES TO THE FORECAST THIS EVENING. PLEASE SEE PREVIOUS DISCUSSION BELOW FOR MORE FORECAST DETAILS. /GREGORIA PREV DISCUSSION... /ISSUED 222 PM EDT THU MAY 1 2014/ SHORT TERM (TONIGHT-SATURDAY NIGHT)... THE DEEP LAYER RIDGE THAT HAS DOMINATED THE WEATHER ACROSS SOUTH FLORIDA THE PAST SEVERAL DAYS WILL BEGIN TO WEAKEN AND SHIFT EAST ON FRIDAY AND INTO THE WEEKEND. THIS IS IN RESPONSE TO THE LARGE CUT- OFF LOW THAT HAS BEEN SPINNING ACROSS THE CENTRAL PART OF THE U.S. GETTING KICKED TO THE NORTHEAST AS UPSTREAM TROUGHS DEVELOP TO ITS WEST. ALL OF THIS WILL AID IN THE ASSOCIATED COLD FRONT TO SLOWLY SHIFT SOUTH DOWN THE FLORIDA PENINSULA OVER THE NEXT 48-60 HOURS. GLOBAL MODELS HAVE BEEN COMING MORE IN LINE WITH EACH OTHER ON THE TIMING ACROSS SOUTH FLORIDA BUT MORE ON THAT LATER. AT ANY RATE, STILL EXPECT SOME SHOWER AND THUNDERSTORM DEVELOPMENT ACROSS THE INTERIOR THIS AFTERNOON AS THE ATMOSPHERE REMAINS QUITE UNSTABLE WITH A LOW LEVEL SSE FLOW. HOWEVER, THE MID LEVEL LAPSE RATES ARE NOT AS IMPRESSIVE AS THE PAST FEW DAYS WITH A 3-6KM LAPSE RATE OF 5.6C/KM THIS MORNING COMPARED TO 6.3C/KM FROM WEDNESDAY MORNING AND 7C/KM ON MONDAY. AS THE FRONT SLOWLY SLIDES TO THE SOUTH ON FRIDAY AND OVER THE EARLY PART OF THE WEEKEND, MOISTURE WILL BE ON THE INCREASE ESPECIALLY BY SATURDAY. FORECAST SOUNDINGS SHOW PWAT REMAINING SIMILAR ON FRIDAY TO TODAY AT AROUND 1.25-1.35 INCHES BUT THEN INCREASING TO 1.6-1.8 INCHES BY SATURDAY AFTERNOON. HOWEVER, THE 500MB TEMPERATURES WARM OVER THE NEXT FEW DAYS WITH THE RANGE OF -7.5C TO -9C TODAY WARMING TO RANGE OF -7C TO -8C BY SATURDAY AFTERNOON. IN OTHER WORDS, MID LEVEL LAPSE RATES WILL BECOME EVEN MORE UNIMPRESSIVE EARLY IN THE WEEKEND ALONG WITH THE FLOW BECOMING UNIDIRECTIONAL WELL AHEAD OF THE FRONT. HOWEVER, DUE TO A WARM SURFACE FLOW ALONG WITH THE CLOSE PROXIMITY OF THE FRONT BY SATURDAY THERE COULD BE SOME STRONGER WIND GUSTS WITH SOME OF THE CELLS. LONG TERM (SUNDAY-THURSDAY)... AS MENTIONED EARLIER ABOUT MODEL CONSENSUS, THE GFS, ECMWF AND NAM ARE ALL SHOWING THE FRONT MOVING ACROSS SOUTH FLORIDA LATE SATURDAY INTO EARLY SUNDAY. SO THINK THE NON POP FORECAST FOR SUNDAY MAY HAVE BEEN A LITTLE PREMATURE SO WILL INCREASE POPS ON SUNDAY TO 30% FOR THE SOUTHERN PORTIONS AND TAILORING DOWNWARD FARTHER TO THE NORTH. THE REMAINDER OF THE EXTENDED PERIOD LOOKS TO BE A DRY FORECAST AS A DEEP LAYER RIDGE ONCE AGAIN BUILDS ACROSS SOUTH FLORIDA. MARINE... THE WINDS WILL BECOME A MORE SOUTHERLY DIRECTION FOR FRIDAY INTO EARLY PART OF THE WEEKEND. THE WINDS WILL THEN VEER TO A NORTHERLY DIRECTION ON SUNDAY INTO EARLY NEXT WEEK...AS WIND SPEEDS REMAIN AROUND 15 KNOTS. THIS WILL KEEP THE SEAS BELOW 6 FEET IN BOTH THE ATLANTIC AND GULF WATERS OF SOUTH FLORIDA THROUGH LATE THIS WEEK BEFORE INCREASING TO AROUND 7 FEET BY LATE THIS WEEKEND. SMALL NORTHEAST SWELL WILL BUILD INTO SOUTH FLORIDA ATLANTIC WATERS INTO THIS WEEKEND. THESE NORTHEAST SWELLS WILL ALLOW FOR THE CONTINUATION OF THE RISK OF RIP CURRENTS ALONG THE EAST COAST BEACHES OF SOUTH FLORIDA THROUGH THE WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 88 75 87 70 / 30 20 50 30 FORT LAUDERDALE 87 77 88 73 / 10 10 40 30 MIAMI 87 76 87 73 / 10 10 40 30 NAPLES 86 74 83 69 / 10 20 50 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...HIGH RIP CURRENT RISK UNTIL 8 AM EDT THIS MORNING FOR FLZ168. AM...NONE. GM...NONE. && $$ SHORT TERM...54/BNB LONG TERM....54/BNB AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
325 PM EDT FRI MAY 2 2014 .SYNOPSIS... A WEAK AREA OF LOW PRESSURE WILL DEVELOP OFFSHORE TONIGHT AND PULL AWAY FROM THE REGION. HIGH PRESSURE WILL THEN BUILD ACROSS THE SOUTHEAST STATES AND EVENTUALLY INTO THE WESTERN ATLANTIC SUNDAY THROUGH MUCH OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... THIS EVENING AND TONIGHT...CURRENT REGIONAL RADAR TRENDS CONTINUE TO SHOW THE STREAM OF RAINFALL ASSOCIATED WITH THE UPPER JET DIVERGENCE AND THE PLUME OF DEEP MOISTURE WILL REMAIN OFFSHORE. INLAND AREAS ARE EXPECTED TO STAY DRY...WITH JUST A SLIGHT CHANCE FOR PERIODIC SHOWERS. ANYTHING THAT DOES FALL WILL PRODUCE LITTLE TO NO MEASURABLE RAINFALL AND WILL ORIGINATE OUT OF MAINLY MID LEVEL CLOUDS. AREAS ALONG THE COAST STAND A BIT OF A BETTER CHANCE OF SEEING MEASURABLE RAIN...BUT EVEN HIGHER RESOLUTION MODELS SUCH AS THE RAP KEEP THESE AREAS LARGELY DRY. THE HIGHER POPS ARE CONFINED TO THE ADJACENT COASTAL WATERS WITH A DRY FORECAST IN PLACE BY LATE TONIGHT. THE ELONGATED MID/UPPER LEVEL TROUGH TO THE WEST WILL FINALLY BEGIN TO MOVE EASTWARD TONIGHT...WHICH WILL NUDGE THE DEEP MOISTURE FEED FURTHER OFFSHORE. MODEL TIME HEIGHTS AND SOUNDINGS SHOW THAT A SOLID MID/UPPER LEVEL CLOUD DECK WILL STICK AROUND FOR MUCH OF THE NIGHT. WE MAY START TO SEE SOME THINNING AND SCATTERING VERY LATE...BUT AT LEAST MOSTLY CLOUDY SKIES ARE EXPECTED. LOWS WILL BE COOLER THAN PREVIOUS NIGHTS...BUT THE EXTENSIVE CLOUD COVER WILL KEEP TEMPERATURES UP A BIT. LOOK FOR LOWS TO FALL INTO THE LOW 50S INLAND...RANGING TO THE MID TO UPPER 50S ALONG THE COAST. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/... SATURDAY...THIS WILL BE A TRANSITION DAY AS THE ELONGATED UPPER TROUGH AXIS SHIFTS OFF THE EASTERN SEABOARD...BRINGING CLEARING SKIES...WARMER TEMPERATURES...AND RAIN FREE CONDITIONS TO THE REGION. THERE WILL STILL BE SOME LINGERING WEAK COLD ADVECTION WHICH COULD KEEP AFTERNOON HIGH TEMPERATURES JUST BELOW SEASONAL NORMALS...BUT OVERALL EXPECT TEMPERATURES TO CLIMB INTO THE MID TO UPPER 70S. A RELATIVELY WEAK FLOW AND CLEAR SKIES WILL ALLOW OVERNIGHT TEMPERATURES TO DIP INTO THE LOWER 50S INLAND AND UPPER 50S ALONG THE COAST. SUNDAY THROUGH MONDAY...EXPECT RISING HEIGHTS AS A BROAD UPPER RIDGE BUILDS EASTWARD ACROSS THE CENTRAL UNITED STATES. AT THE SURFACE...HIGH PRESSURE WILL NUDGE INTO THE REGION FROM THE WEST...RESULTING IN PLENTY OF SUNSHINE AND A CONTINUED WARMING TREND. HIGH TEMPERATURES ARE EXPECTED TO CLIMB ABOVE SEASONAL NORMALS WITH MID 80S ON SUNDAY AND UPPER 80S ON MONDAY. IN FACT...THICKNESS VALUES SUGGEST TEMPERATURES NEAR 90 DEGREES WILL BE POSSIBLE ON MONDAY. SUNDAY NIGHT TEMPERATURES WILL ALSO REFLECT THIS WARMING TREND WITH LOWS IN THE UPPER 50S INLAND AND MID 60S ALONG THE COAST. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A BROAD UPPER LEVEL RIDGE WILL DOMINATE THE EASTERN UNITED STATES PATTERN FOR MUCH OF THE EXTENDED PERIOD...MAINTAINING UNSEASONABLY WARM TEMPERATURES AND DRY CONDITIONS. TEMPS WILL MODERATE SLIGHTLY BY LATE NEXT WEEK AS THE UPPER RIDGE BEGINS TO BREAK DOWN. WE ARE NOW SHOWING HIGHS IN THE UPPER 80S TO NEAR 90 TUESDAY THROUGH THURSDAY...THEN MIDDLE 80S ON FRIDAY. WE WILL PROBABLY NOT BREAK ANY RECORD HIGHS SINCE THEY ARE ALL IN THE MIDDLE 90S FOR OUR THREE CLIMATE SITES NEXT WEEK. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... VFR CONDITIONS WILL PREVAIL THROUGH 18Z SATURDAY. THERE MAY BE A BRIEF PERIOD OF LIGHT RAIN AT EITHER SITE IN THE NEXT FEW HOURS...BUT NOTHING WITH ENOUGH INTENSITY TO DECREASE VISIBILITIES. A SOLID MID LEVEL DECK WILL STAY IN PLACE AND THEN CLEAR OUT STARTING TOMORROW MORNING. EXTENDED AVIATION OUTLOOK...VFR. && .MARINE... TONIGHT...QUIET CONDITIONS WILL CONTINUE ESPECIALLY EARLY IN THE PERIOD. WINDS WILL BE LIGHT AND VARIABLE EARLY ON...BEFORE INCREASING AND MORE WESTERLY LATE AS A WEAK SURFACE LOW RIDES NORTHEASTWARD ALONG THE FRONT TO THE EAST. THIS INCREASE WILL BE QUITE MODEST HOWEVER...WITH SPEEDS 15 KT OR LESS. SEAS WILL BE 2 FT WITHIN 20 NM AND 2-3 FT BEYOND. SATURDAY THROUGH WEDNESDAY...A PASSING UPPER LEVEL TROUGH WILL ELEVATE WINDS SLIGHTLY SATURDAY...BUT OVERALL EXPECT RATHER TRANQUIL CONDITIONS TO PERSIST ACROSS THE MARINE AREA. IN FACT...THIS BRIEF SURGING WILL STILL REMAIN BELOW SMALL CRAFT LEVELS. THROUGH MID WEEK...EXPECT WINDS 15 KNOTS OR LESS WITH SEAS 1 TO 2 FEET ACROSS THE NEAR SHORE WATERS AND NO MORE THAN 4 FEET ACROSS THE OUTER GEORGIA WATERS. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ SYNOPSIS... NEAR TERM...BSH SHORT TERM...JHP LONG TERM...JRL AVIATION...BSH MARINE...BSH/JHP
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
125 AM EDT FRI MAY 2 2014 .UPDATE... /ISSUED AT 852 PM EDT THU MAY 1 2014/ HIGH PRESSURE WILL CONTINUE TO BUILD IN FROM THE WEST OVERNIGHT. SHORTWAVE ENERGY STILL PROGGED TO ENHANCE LIGHT PRECIPITATION ACROSS THE SOUTHERN ZONES TOWARDS SUNRISE. HRRR STILL SUPPORTS THIS...AND WILL NOT MAKE CHANGES TO POPS AT THIS TIME. HAVE ONLY MADE MINOR CHANGES TO THE HOURLY TEMPS/DEWS. && .PREV DISCUSSION... /ISSUED 721 PM EDT THU MAY 1 2014/ PREV DISCUSSION... /ISSUED 346 PM EDT THU MAY 1 2014/ SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... LATEST SURFACE ANALYSIS SHOWS FRONTAL BOUNDARY MOVING PAINFULLY SLOW THROUGH THE FORECAST AREA WITH IT NOW STRETCHING FROM GREENVILLE THROUGH ATHENS AND ATLANTA. AHEAD OF THE FRONT...DEEPER MOISTURE HAS COMBINED WITH SUBTLE UPPER LEVEL ENERGY TO RESULT IN CONTINUED GOOD COVERAGE OF SHOWERS AND ISOLATED THUNDERSTORMS. WITH THIS PARTICULAR SHORTWAVE SHIFTING EAST...SHOULD SEE A REDUCTION IN POPS THIS EVENING WITH CURRENT LIKELY COVERAGE REDUCED TO CHANCE POPS. THIS BREAK LOOKS TO BE SHORT LIVED HOWEVER AS ANOTHER SHORTWAVE MOVES IN FROM ALABAMA AROUND 06Z TONIGHT ENHANCING AND LIFTING SHIELD OF PRECIPITATION NORTHWARD. HAVE LEANED CLOSE TO THE NAMMB WHICH HAS PERFORMED WELL OF LATE AND BRING HEALTHY POP COVERAGE OF 80 PERCENT TO EXTREME SOUTHERN TIER BUT TAPER OFF RAPIDLY TO LESS THAN 20 FOR THE ATLANTA METRO. FEEL LIKE THUNDER THREAT MAY BE OVER FOR THIS AFTERNOON AND EVENING BUT MAY RETURN AS EARLY AS MID MORNING WITH ONLY ISOLATED TSRA PLANNED. HAVE GONE ABOVE GUIDANCE ON TEMPS TONIGHT AS EXTENSIVE CLOUD COVER SHOULD KEEP SIGNIFICANT TEMP DROP IN CHECK. FINAL SHORTWAVE FRIDAY NIGHT AND SATURDAY MORNING IS MORE SUBSTANTIAL AND SHOULD PRODUCE A CLEARING TREND FOR THE WEEKEND WITH FRONT FINALLY CLEARING THE AREA AND A RETURN TO MOSTLY SUNNY CONDITIONS. DEESE LONG TERM /SATURDAY THROUGH THURSDAY/... NO CHANGES MADE TO THE EXTENDED FORECAST AS A DRY FORECAST WILL CONTINUE. WE WILL MOSTLY BE UNDER MOIST SOUTHERLY FLOW THROUGH THE EXTENDED...SO WE WILL SEE CLOUDS OFF AN ON THROUGH DAY 7 BUT NO PRECIP EXPECTED. A DRY BACKDOOR COLD FRONT MOVES CLOSE TO THE FAR NE EARLY MONDAY BUT LOOKS TO STALL AND MOVE BACK NE INTO TUESDAY. THE FRONT WILL HAVE VERY LIMITED MOISTURE SO AGAIN NO PRECIP IS EXPECTED WITH IT. HIGH PRESSURE ALOFT WILL BUILD INTO THE AREA TUESDAY AND WEDNESDAY CONTINUING TO KEEP THINGS DRY. FORECAST LOW TEMPERATURES RUNNING AROUND 5 DEGREES BELOW NORMAL SATURDAY MORNING THEN NEAR TO ABOVE NORMAL SUNDAY TO THURSDAY. 01 && .AVIATION... 06Z UPDATE... VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST AT ALL SITES. A SHORT WAVE WILL BRING 4000-5000FT CIGS INTO CSG/MCN THIS MORNING AND CONTINUE INTO THIS AFTERNOON. A CU FIELD SHOULD FORM BRINGING SCT-BKN050 THIS AFTERNOON. ALL CIGS SHOULD DISSIPATE BY OR AROUND SUNSET THIS EVENING. WINDS WILL BE NEAR CALM EARLY THIS MORNING...AND THEN LIGHT WESTERLY THROUGH THE DAY TODAY. //ATL CONFIDENCE...06Z UPDATE... HIGH CONFIDENCE ALL ELEMENTS. && .PRELIMINARY POINT TEMPS/POPS... ATHENS 50 72 48 77 / 20 20 5 5 ATLANTA 52 70 51 75 / 10 10 5 5 BLAIRSVILLE 44 65 43 71 / 5 5 5 5 CARTERSVILLE 46 69 46 75 / 5 5 5 5 COLUMBUS 53 72 51 77 / 50 50 20 5 GAINESVILLE 51 68 50 74 / 5 5 0 5 MACON 52 70 48 77 / 60 60 20 5 ROME 46 68 46 76 / 5 5 0 5 PEACHTREE CITY 47 71 45 76 / 20 20 5 5 VIDALIA 57 67 53 76 / 80 80 50 10 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ATWELL LONG TERM....ATWELL AVIATION...ATWELL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
647 PM CDT SAT MAY 3 2014 .UPDATE... ISSUED AT 543 PM CDT SAT MAY 3 2014 BASED ON RADAR AND OBS I HAVE UPDATED FORECAST TO RAISE POPS ACROSS W/SW PORTIONS OF CWA INTO EARLY EVE FOR BAND OF SHOWERS ATTENDANT TO MID LEVEL FRONTOGENETICAL FORCING. WITH CONSIDERABLE T/TD SPREADS NOT EXPECTING MUCH MORE THAN A TRACE TO A COUPLE HUNDREDTHS OF AN INCH. && .SYNOPSIS... ISSUED AT 312 PM CDT SAT MAY 3 2014 SPRAWLING LOW PRESSURE OVER HUDSON BAY WAS PROVIDING THE MID MISSISSIPPI VALLEY WITH A BREEZY AND RELATIVELY MILD SATURDAY. FOR THE MOST PART THE REGION WAS DRY WITH THE EXCEPTION OF A NARROW BAND OF RAIN FROM SOUTHEAST SOUTH DAKOTA INTO SOUTH CENTRAL IOWA. THE RAIN WAS COMING FROM A MID CLOUD DECK WITH A DEEP AND DRY SUB CLOUD LAYER WHICH WAS CAUSING MOST OF THE RAIN TO EVAPORATE BEFORE REACHING THE GROUND. THE RAIN AND MID CLOUDS WERE OCCURRING IN A REGION OF MID LEVEL FGEN ON THE SOUTHWEST FLANK OF A 120KT H3 JET STREAK OVER THE NORTH CENTRAL U.S. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 312 PM CDT SAT MAY 3 2014 THE REGION WILL REMAIN IN NORTHWEST FLOW THROUGH SUNDAY AS AN UPPER RIDGE MOVES INTO THE HIGH PLAINS AND AN UPPER LOW OVER ONTARIO WEAKENS. AS THE UPPER RIDGE MOVES EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE WESTERN GREAT LAKES WHILE A WARM FRONT SETS UP FROM CENTRAL PLAINS INTO THE LOWER OHIO VALLEY. THE FIRST CONCERN WILL BE THE HIGH BASED RAIN OVER THE WESTERN HALF OF IOWA. THE HRRR HAS BEEN CONSISTENT IN BRINGING THE RAIN ACROSS THE DVN CWFA LATE THIS AFTERNOON AND EARLY THIS EVENING. HOWEVER THE HRRR HAS ALSO BEEN CONSISTENTLY TO FAR NORTHEAST WITH THE PRECIPITATION. ALSO THE RAIN SEEMS TO CORRELATE WELL WITH FGEN IN THE 700-500MB LAYER WHICH THE RAP SHOWS WEAKENING WITH TIME. FOR NOW WILL GO WITH SOME SPRINKLES IN THE SOUTH THIS EVENING...THINKING THAT MOST OF THE PRECIPITATION WILL DISSIPATE BEFORE REACHING THE GROUND. LATER TONIGHT AND SUNDAY MORNING MODELS SHOW THE RIGHT ENTRANCE REGION OF THE NORTH CENTRAL U.S. H3 JET MOVING THROUGH THE REGION. MID/LOW LEVEL FGEN AND UPPER DIVERGENCE ASSOCIATED WITH THE JET ARE PROGGED TO SUPPORT ANOTHER BAND OF RAIN THAT SHOULD IMPACT AREAS MAINLY NORTH OF I80 SUNDAY MORNING. GIVEN THE CONSISTENCY BETWEEN THE MODELS WITH THIS FEATURE...HAVE INCREASED POPS TO LIKELY FOR AREAS MAINLY NORTH OF HIGHWAY 30. THE RAIN SHOULD BE EAST OF THE FORECAST AREA BY EARLY AFTERNOON WITH DRY WEATHER EXPECTED THE REST OF THE DAY. WITH INCREASING MID CLOUDS OVERNIGHT TONIGHT TEMPERATURES WERE KEPT ON THE MILDER SIDE OF GUIDANCE MAINLY IN THE 40S. SUNDAY WITH THE SURFACE HIGH SETTING UP TO OUR NORTH AND THE DEVELOPING WARM FRONT SOUTH...A DECENT THERMAL GRADIENT WILL DEVELOP ACROSS THE REGION. HIGHS SHOULD RANGE FROM NEAR 70 IN THE FAR SOUTH TO THE MIDDLE 50S NORTH. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 312 PM CDT SAT MAY 3 2014 FORECAST FOCUS IS ON WELCOMED WARMING TREND NEXT WEEK AND ON PCPN CHANCES MID TO LATE WEEK. SUNDAY NIGHT...WEAK DISTURBANCE TO HAVE EXITED THE AREA WITH HIGH PRESSURE BUILDING INTO THE GREAT LAKES REGION. WITH A STATIONARY BOUNDARY WELL TO OUR SOUTH AND EASTERLY FLOW OFF THE GREAT LAKES... WILL SEE TEMPS DROP INTO THE UPPER 30S/LOW 40S UNDER PARTLY CLOUDY SKIES. MONDAY-TUESDAY...EASTERLY LOW LEVEL FLOW AND SOME MID-HIGH LEVEL CLOUDS WILL BE THE NORM AS HIGH PRESSURE DRIFTS OVER THE GREAT LAKES AND A FRONTAL BOUNDARY REMAINS SOUTH OF THE AREA DRAPED OVER MISSOURI AND SOUTHERN ILLINOIS. HIGHS WILL REACH THE LOWER 60S NORTH TO LOWER 70S IN THE FAR SOUTH WHICH IS NEAR NORMAL FOR EARLY MAY. TUESDAY NIGHT-WEDNESDAY...WARM FRONT PROGGED TO LIFT NORTH INTO NORTHEAST IOWA AND SOUTHERN WISCONSIN BY EARLY EVENING WEDNESDAY. CONVERGENCE ALONG THE FRONT COUPLED WITH A 40KT LLJ SHOULD ALLOW FOR SOME OVERNIGHT ELEVATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY ACROSS THE NORTHERN HALF OF THE CWA. MUCAPES BETWEEN 1500-2000 J/KG AND PROGGED 40KT 0-6KM SHEAR VALUES SUGGEST SMALL SEVERE THREAT WITH ANY STRONG STORM THAT WOULD DEVELOP TO PRODUCE MARGINAL SEVERE HAIL. OVERNIGHT LOW TEMPERATURES WILL DEPEND LARGELY ON SPEED OF WARM FRONT LIFTING NORTH. FOR NOW WILL GO WITH LOWER 50S NORTH TO THE LOWER 60S SOUTH. CWA TO BE COMPLETELY IN THE WARM SECTOR BY WEDNESDAY AFTERNOON WITH TEMPERATURES SOARING INTO THE UPPER 70S/MIDDLE 80S AND A STRONG CAP IN PLACE OVER THE AREA. IT WILL ALSO FEEL HUMID...WITH DEWPOINTS IN THE UPPER 50S AND LOWER 60S. WEDNESDAY NIGHT...STRONG LLJ TO ONCE AGAIN DEVELOP OVERNIGHT OVER THE PLAINS WITH STORMS DEVELOPING ON THE NOSE OF JET ACROSS CENTRAL IOWA. LATEST MODELS TRACK THESE STORMS EAST AND WEAKEN AS THEY NEAR THE CWA. NONETHELESS HAVE MAINTAINED HIGH CHANCE POPS ACROSS THE WEST FOR THIS BUT MAY NEED TO BE LOWERED IF MODELS CONTINUE TO SHOW WEAKER FORCING. STEEP MID LEVEL LAPSE RATES ALSO SUGGEST A FEW RUMBLES OF THUNDER WILL BE POSSIBLE AS WELL. TEMPERATURES WILL BE VERY MILD WEDNESDAY NIGHT DUE TO REGION IN THE WARM SECTOR WITH LOWS ONLY DROPPING INTO THE LOWER 60S. THURSDAY...WARM AND HUMID CONDITIONS WILL BE COMMON AS STRONG SOUTHERLY FLOW CONTINUES AHEAD OF SURFACE LOW IN THE PLAINS. LATEST 12Z MODEL SUITE HAS SLOWED THE PROGRESSION OF THE COLD FRONT SOME WITH IT NOT ARRIVING INTO THE WESTERN PART OF THE CWA UNTIL EARLY FRIDAY. THIS SLOWER FRONT WILL HELP BOOST TEMPERATURES AND HAVE RAISED READINGS A FEW DEGREES WITH FORECAST HIGHS SIMILAR TO WEDNESDAY. STRONG DAYTIME HEATING WILL DESTABILIZE THE ATMOSPHERE DURING THE DAY AND COMBINED WITH A FAVORABLE JET AXIS/STRONG SHEAR PROFILE SUGGESTS STRONG TO SEVERE STORMS WILL BE POSSIBLE DURING THE LATE AFTERNOON AND EVENING HOURS. SPC CURRENTLY HAS THE AREA OUTLINED FOR THIS IN ITS DAY 4-8 OUTLOOK AND WILL CONTINUE TO MONITOR CLOSELY THIS TIME FRAME BY LATER SHIFTS. REST OF EXTENDED...COLD FRONT TO PUSH THROUGH THE AREA FRIDAY MORNING WITH CLEARING SKIES AND MORE COMFORTABLE CONDITIONS AS DEW POINTS DROP INTO THE LOWER 50S. DRY CONDITIONS AND SEASONABLE TEMPERATURES WILL END THE WORK WEEK WITH HIGHS IN THE UPPER 60S/LOW 70S AND LOWS IN THE UPPER 40S/LOWER 50S. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 634 PM CDT SAT MAY 3 2014 VFR CONDITIONS WILL PERSIST THROUGH THE TAF CYCLE. GUSTY NORTHWEST WINDS WILL DIMINISH BLO 10 KTS WITH SUNSET THEN GRADUALLY TURN TO NORTH OVERNIGHT AS HIGH PRESSURE BUILDS IN. ON SUNDAY...WINDS WILL TURN TO NORTHEAST AND INCREASE 10-15 KTS. A COUPLE OF WEAK DISTURBANCES WILL BRING BOUTS OF MID CLOUDINESS THROUGH THE PERIOD. A FEW SPRINKLES AND LIGHT HIGH BASED SHOWERS WILL ALSO BE FOUND OVER SOUTHEAST IOWA INTO WEST CENTRAL ILLINOIS EARLY THIS EVENING...AND AGAIN SUNDAY MORNING MAINLY OVER NORTHEAST IOWA INTO NORTHWEST ILLINOIS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...05 SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...GROSS AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
516 PM MDT SAT MAY 3 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 206 PM MDT SAT MAY 3 2014 FRONT CURRENTLY DRAPE ACROSS THE FORECAST AREA. 70S ARE OVER THE NORTHEAST HALF WITH 80S OVER THE SOUTHWEST HALF. THIS BOUNDARY WILL MAKE FOR A DIFFICULT WIND AND TEMPERATURE FORECAST THROUGH TOMORROW. TEMPERATURES SHOULD STAY WARM WHERE THE WINDS STAY UP. SOME LOCATIONS ON BOTH SIDES WILL HAVE LIGHTER WINDS SO COULD SEE SOME LOCATIONS BEING ABLE TO DROP. AS TODAY...MODELS DIFFER ON THE POSITION OF WHERE THE FRONT IS DURING THE DAY. THE ECMWF IS FURTHER WEST WITH FRONT AND IS THE COOLEST. OF THE MODELS THAT GO OUT LONG ENOUGH...THE NAM IS CLOSER TO THE RAP AND HRRR WHICH ARE DOING WELL RIGHT NOW. MOST OF THE OUTPUT HOW MORE OF THE FORECAST ON THE WARM SIDE...AND WILL BE GOING THAT DIRECTION. AT THIS TIME THE NORTHEAST CORNER LOOKS TO BE THE COOLEST WITH SUMMER-LIKE TEMPERATURES EXPECTED OVER TO THE WEST OF THE FRONT. REFER TO THE CLIMATE SECTION BELOW. ALSO REFER TO THE FIRE SECTION BELOW FOR TOMORROWS FIRE WEATHER DISCUSSION. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 258 PM MDT SAT MAY 3 2014 MAIN CONCERNS WITH THE EXTENDED FORECAST ARE POSSIBLE FIRE WEATHER CONDITIONS AND PRECIPITATION ASSOCIATED WITH A PASSING LONGWAVE TROUGH. WARM AND DRY CONDITIONS ARE ANTICIPATED INTO THE BEGINNING OF NEXT WEEK. A SLOW COOLING TREND SHOULD BEGIN MONDAY WITH COOLING 850 MB TEMPERATURES AND A WEAK COLD FRONT LINGERING. MUCH HIGHER DEWPOINTS AND HUMIDITY SHOULD POOL ALONG AND BEHIND THE COLD FRONT...ALLOWING FOR A CHANCE OF FOG BOTH SUNDAY NIGHT AND MONDAY NIGHT. DURING THE DAYLIGHT HOURS...CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE SOUTH OF THE FRONT WHERE SOUTHWEST WINDS INCREASE AND VERY DRY AIR REMAINS. FUEL STATUS REMAINS THE MAIN ISSUE WITH GREEN-UP ONGOING ACROSS THE TRI-STATE AREA. A STRONG LONGWAVE TROUGH SWINGS ACROSS THE HIGH PLAINS DURING THE MIDDLE OF THE WEEK...BRINGING THE ONLY CHANCES FOR PRECIPITATION IN THE LONG TERM FORECAST. DUE TO DRY AIR REMAINING ACROSS PORTIONS OF THE TRI-STATE AREA...PRECIPITATION CHANCES WILL BE CONFINED TO LOCATIONS ALONG AND BEHIND THE FRONT WHERE AVAILABLE MOISTURE IS HIGHER. THE DRYLINE REMAINS WELL TO THE EAST DURING PERIODS OF BEST ATMOSPHERIC LIFT AND INSTABILITY SO BEST CHANCES FOR SEVERE WEATHER SHOULD BE CONFINED TO EASTERN KANSAS AND OKLAHOMA. WITH INCREASING SHEAR AND INSTABILITY...CAN NOT RULE OUT A FEW STRONG TO SEVERE STORMS BUT DO NOT THINK A WIDESPREAD OUTBREAK IS LIKELY AT THIS TIME. PRECIPITATION SHOULD BE SPORADIC SO NOT EVERYBODY WILL RECEIVE A NEEDED RAINFALL. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 511 PM MDT SAT MAY 3 2014 VFR EXPECTED AT BOTH KGLD AND KMCK THROUGH THE TAF PERIOD. UPPER RIDGE WILL SUPPRESS ANY CHANCES FOR PRECIPITATION. A FRONTAL BOUNDARY STALLED OUT ACROSS THE AREA SEPARATES A HOT DRY AIR MASS TO THE WEST AND A WARM SLIGHTLY MORE MOIST AIR MASS TO THE EAST. KMCK WILL LIE NEAR OR JUST ON THE COOL SIDE OF THE FRONT SUNDAY MORNING. AS A RESULT...THERE IS A LOW PROBABILITY...LESS THAN 10 PERCENT...OF FOG FORMING AROUND SUNRISE. VISIBILITIES MAY BRIEFLY BE REDUCED TO MVFR IF IT WERE TO OCCUR...BUT CONFIDENCE IS LOW AND WILL NOT INCLUDE IN THE KMCK TAF ATTM. && .FIRE WEATHER... ISSUED AT 206 PM MDT SAT MAY 3 2014 LIKE TODAY...THE RELATIVE HUMIDITIES WILL DEFINITELY REACH CRITICAL FIRE WEATHER CONDITIONS. HOWEVER...THERE IS SOME UNCERTAINTY ON FUEL STATUS AND ON THE WINDS. WHAT DATA CAN BE FOUND WOULD INDICATE THAT WE ARE IN GREEN-UP BUT THAT MAY BE MOSTLY FOR GROWING CROPS. WINDS TO THE WEST OF THE FRONT COULD BE GUSTY AND REACH THE NEEDED CRITERIA. HOWEVER...THERE IS A DECENT SPREAD IN THE MODEL OUTPUT ON THE POSITION OF THE FRONT AND RESULTANT WIND SPEEDS. IF THE STRONGER NAM WINDS WORK OUT...THEN SOME LOCATION IN THE SOUTHWEST HALF OF THE AREA COULD REACH CRITICAL FIRE WEATHER CONDITIONS. AT THIS TIME...TOO MUCH UNCERTAINTY TO ISSUE A WATCH WITH THE OVERNIGHT SHIFT NEEDING TO TAKE ANOTHER LOOK AT THIS. && .CLIMATE... ISSUED AT 206 PM MDT SAT MAY 3 2014 MOST OF THE AREA WILL HAVE A CHANCE TO BREAK DAILY RECORDS FOR MAY 4. THE FOLLOWING ARE THE RECORDS FOR SUNDAY. GOODLAND.....91 IN 2012 MCCOOK.......94 IN 2012 BURLINGTON...92 IN 1963 HILL CITY....93 IN 2012 COLBY........92 IN 1924 TRIBUNE......94 IN 1952 YUMA.........89 IN 1962 && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...RRH AVIATION...024 FIRE WEATHER...BULLER CLIMATE...BULLER
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1127 PM EDT SAT MAY 3 2014 .SYNOPSIS... A WEAK RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS SOUTHERN AREAS THROUGH THIS EVENING. LOW PRESSURE WILL DEVELOP TO OUR WEST TONIGHT AND TRACK ACROSS THE STATE ON SUNDAY. THE LOW WILL CONTINUE EAST ACROSS THE MARITIMES SUNDAY NIGHT AND MONDAY.&& .NEAR TERM /THROUGH SUNDAY/... 11:30 PM UPDATE...INCREASED SHOWER COVERAGE OVER CENTRAL AND WESTERN AREAS. OTHERWISE FORECAST REMAINS THE SAME IS MOSTLY CLOUDY SKIES ACROSS THE REGION OVERNIGHT. PREV DISC: UNSETTLED WEATHER WILL CONTINUE THIS TERM AND BEYOND. THE FIRST BATCH OF SHOWERS WILL BE DIMINISHING AND EXITING INTO NEW BRUNSWICK BY THE EVENING AS THE REGION GETS UNDER SOME UPPER RIDGING. SOME BREAKS IN THE CLOUDS THIS AFTERNOON WILL HELP TEMPERATURES TO REBOUND AFTER THE BRIEF SHOWER ACTIVITY TO AROUND 60F EVEN ACROSS THE NORTHERN CWA. TEMPERATURES WILL DROP OFF AFTER SUNSET W/SOME PARTIAL CLEARING ESPECIALLY ACROSS THE CENTRAL AND DOWNEAST, AND THEN LEVEL OFF AS CLOUDS WILL MOVE BACK IN LATER TONIGHT AHEAD OF A MORE ROBUST SYSTEM MOVING OUT OF THE ONTARIO REGION. DECIDED TO FOLLOW THE GEM AND RAP INTO TONIGHT W/A NICE BREAK IN THE PRECIP UP THROUGH LATE EVENING. THIS FEATURE CAN BE SEEN WELL ON THE LATEST SATELLITE WV IMAGERY W/ITS UPPER SUPPORT MOVING INTO THE EASTERN GREAT LAKES. THEREFORE, OVERNIGHT LOWS ARE EXPECTED TO BE IN THE LOW TO MID 40S. THIS ALL HINGES ON CLOUDS ARRIVE SOONER AND DEWPOINTS DROPPING BACK DUE TO PARTIAL CLEARING EARLY ON. THIS WILL NEED TO BE MONITORED. STEADIER RAINFALL IS EXPECTED AFTER MIDNIGHT AND THIS WILL BE MOST PROMINENT ACROSS THE WESTERN AND DOWNEAST. SUNDAY WILL BE MOSTLY A WET DAY W/RAIN AS LOW PRES SLIDES ACROSS THE CENTRAL PART OF THE STATE. AS THE LOW MOVES ACROSS THE REGION, THE CENTRAL AND DOWNEAST REGION GET UNDER A SW FLOW FROM THE SFC THROUGH 700MBS. THE IS POTENTIAL FOR SOME MID-LEVEL DRYING AND W/THE COLD AIR ALOFT, THE AIRMASS DESTABILIZES W/SREF MUCAPES OF 300 J/KG. NAM/GFS SOUNDINGS SUPPORT K INDEX OF 30 AND TOTAL TOTALS OF 55+. LIS DROP TO NEAR 0. THIS COULD BE ENOUGH TO ALLOW FOR SOME CONVECTION AND DECIDED TO A CHANCE FOR TSTMS IN THE AFOREMENTIONED AREAS BY THE AFTERNOON. FURTHER NORTH AND WEST, ATMOSPHERE LOOKS TO BE STABLE ENOUGH KEPT THREAT FOR ANY TSTMS TO A MINIMUM IF NONE AT ALL. HEAVIEST BAND OF RAINFALL IN THE CENTRAL AND DOWNEAST AREAS WHERE BEST CONVERGENCE AND FORCING WILL BE SITUATED. SOME DEFORMATION BANDING PRECIP POSSIBLE ESPECIALLY NORTH OF THE LOW. TOTAL QPF FOR THE EVENT IS EXPECTED TO BE ON THE ORDER OF 0.30 TO 0.75". THIS ADDITIONAL WILL BE ADDED TO THE RIVER BASINS AND CAUSE THE STAGES TO RISE SOME BUT NO PROBLEMS EXPECTED.&& .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE IS EXPECTED TO MOVE EASTWARD INTO THE ATLANTIC SUNDAY NIGHT. A STRONG NORTHWEST PRESSURE GRADIENT WILL DEVELOP ACROSS THE REGION BEHIND THE LOW AS HIGH PRESSURE BUILDS IN FROM THE WEST. EXPECT SHOWERS TO PERSIST BEHIND THE LOW AS CYCLONIC FLOW REMAINS BEHIND THE SYSTEM ALOFT. FOR POPS AND QPF WILL BLEND THE NAM...GFS...SREF AND ECMWF. SKY COVER FROM THE NAM...GFS...ECMWF. TEMPERATURE AND DEW POINT FROM HE SUPPER BLEND. HAVE USED THE MOSG25 FOR SUSTAINED WIND SPEED. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE IS EXPECTED TO WEAKEN AND CREST THEN CREST OVER THE REGION WEDNESDAY NIGHT. A WARM FRONT IS EXPECTED TO APPROACH FROM THE SOUTH WEST THURSDAY AND FRIDAY THEN MOVE ACROSS THE STATE SATURDAY. A COLD FRONT WILL THEN FOLLOW AS INTENSE LOW PRESSURE MOVES ACROSS CENTRAL CANADA. WILL USE HE SUPPER BLEND TO POPULATE ALL GRIDS. && .AVIATION /04Z SUNDAY THROUGH THURSDAY/... NEAR TERM: VFR GOING TO MVFR AFTER 06Z W/THE POTENTIAL FOR IFR ACROSS KBGR AND KBHB SUNDAY MORNING AND THE IFR EDGING INTO THE NORTHERN TERMINALS BY SUNDAY AFTERNOON. SOME IMPROVEMENT TO MVFR FOR KBGR AND KBHB AND EVEN VFR AS THIS REGION GETS ON THE SOUTH SIDE OF THE LOW AS SW FLOW SETS UP. SHORT TERM: IFR CONDITIONS ARE EXPECTED SUNDAY NIGHT THEN IMPROVING TO VFR CONDITIONS MONDAY. MVFR CONDITIONS EXPECTED TUESDAY. VFR CONDITIONS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM: NO HEADLINES ANTICIPATED THROUGH SUNDAY. THERE IS A SSW SWELL ATTM ON THE WATERS W/WAVE HEIGHTS OF 3-4 FT. EXPECT THIS SWELL TO CONTINUE INTO SUNDAY. A 30KT LLVL JET FROM 925-850MBS IS FORECAST TO MOVE ACROSS THE WATERS LATER TONIGHT INTO EARLY SUNDAY. THIS WILL BRING THE WINDS UP A BIT W/GUST TO 20 KTS ESPECIALLY OVER THE OUTER WATERS. SHORT TERM: FOR SUSTAINED WINDS WILL USE A BLEND OF THE SREF AND GFS40 THEN TRANSITION TO THE SUPPER BLEND LATE TUESDAY. FOR WAVES: WILL USE THE SWAN/NAM OUT TO 0000Z TUESDAY THEN TRANSITION TO THE WNA/4. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT/MCB SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...HEWITT/MIGNONE MARINE...HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1019 PM EDT SAT MAY 3 2014 .SYNOPSIS... A WEAK RIDGE OF HIGH PRESSURE WILL SLIDE ACROSS SOUTHERN AREAS THROUGH THIS EVENING. LOW PRESSURE WILL DEVELOP TO OUR WEST TONIGHT AND TRACK ACROSS THE STATE ON SUNDAY. THE LOW WILL CONTINUE EAST ACROSS THE MARITIMES SUNDAY NIGHT AND MONDAY.&& .NEAR TERM /THROUGH SUNDAY/... UPDATE: AS OF LATE EVE...SKIES REMAIN M/C ACROSS THE REGION W/ A FEW LGT LIFTING NEWRD ACROSS MAINLY THE WRN HALF OF THE FA. CURRENT FCST ON TRACK W/ NO CHANGES NEEDED THIS UPDATE CYCLE... PREV DISC: UNSETTLED WEATHER WILL CONTINUE THIS TERM AND BEYOND. THE FIRST BATCH OF SHOWERS WILL BE DIMINISHING AND EXITING INTO NEW BRUNSWICK BY THE EVENING AS THE REGION GETS UNDER SOME UPPER RIDGING. SOME BREAKS IN THE CLOUDS THIS AFTERNOON WILL HELP TEMPERATURES TO REBOUND AFTER THE BRIEF SHOWER ACTIVITY TO AROUND 60F EVEN ACROSS THE NORTHERN CWA. TEMPERATURES WILL DROP OFF AFTER SUNSET W/SOME PARTIAL CLEARING ESPECIALLY ACROSS THE CENTRAL AND DOWNEAST, AND THEN LEVEL OFF AS CLOUDS WILL MOVE BACK IN LATER TONIGHT AHEAD OF A MORE ROBUST SYSTEM MOVING OUT OF THE ONTARIO REGION. DECIDED TO FOLLOW THE GEM AND RAP INTO TONIGHT W/A NICE BREAK IN THE PRECIP UP THROUGH LATE EVENING. THIS FEATURE CAN BE SEEN WELL ON THE LATEST SATELLITE WV IMAGERY W/ITS UPPER SUPPORT MOVING INTO THE EASTERN GREAT LAKES. THEREFORE, OVERNIGHT LOWS ARE EXPECTED TO BE IN THE LOW TO MID 40S. THIS ALL HINGES ON CLOUDS ARRIVE SOONER AND DEWPOINTS DROPPING BACK DUE TO PARTIAL CLEARING EARLY ON. THIS WILL NEED TO BE MONITORED. STEADIER RAINFALL IS EXPECTED AFTER MIDNIGHT AND THIS WILL BE MOST PROMINENT ACROSS THE WESTERN AND DOWNEAST. SUNDAY WILL BE MOSTLY A WET DAY W/RAIN AS LOW PRES SLIDES ACROSS THE CENTRAL PART OF THE STATE. AS THE LOW MOVES ACROSS THE REGION, THE CENTRAL AND DOWNEAST REGION GET UNDER A SW FLOW FROM THE SFC THROUGH 700MBS. THE IS POTENTIAL FOR SOME MID-LEVEL DRYING AND W/THE COLD AIR ALOFT, THE AIRMASS DESTABILIZES W/SREF MUCAPES OF 300 J/KG. NAM/GFS SOUNDINGS SUPPORT K INDEX OF 30 AND TOTAL TOTALS OF 55+. LIS DROP TO NEAR 0. THIS COULD BE ENOUGH TO ALLOW FOR SOME CONVECTION AND DECIDED TO A CHANCE FOR TSTMS IN THE AFOREMENTIONED AREAS BY THE AFTERNOON. FURTHER NORTH AND WEST, ATMOSPHERE LOOKS TO BE STABLE ENOUGH KEPT THREAT FOR ANY TSTMS TO A MINIMUM IF NONE AT ALL. HEAVIEST BAND OF RAINFALL IN THE CENTRAL AND DOWNEAST AREAS WHERE BEST CONVERGENCE AND FORCING WILL BE SITUATED. SOME DEFORMATION BANDING PRECIP POSSIBLE ESPECIALLY NORTH OF THE LOW. TOTAL QPF FOR THE EVENT IS EXPECTED TO BE ON THE ORDER OF 0.30 TO 0.75". THIS ADDITIONAL WILL BE ADDED TO THE RIVER BASINS AND CAUSE THE STAGES TO RISE SOME BUT NO PROBLEMS EXPECTED.&& .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... LOW PRESSURE IS EXPECTED TO MOVE EASTWARD INTO THE ATLANTIC SUNDAY NIGHT. A STRONG NORTHWEST PRESSURE GRADIENT WILL DEVELOP ACROSS THE REGION BEHIND THE LOW AS HIGH PRESSURE BUILDS IN FROM THE WEST. EXPECT SHOWERS TO PERSIST BEHIND THE LOW AS CYCLONIC FLOW REMAINS BEHIND THE SYSTEM ALOFT. FOR POPS AND QPF WILL BLEND THE NAM...GFS...SREF AND ECMWF. SKY COVER FROM THE NAM...GFS...ECMWF. TEMPERATURE AND DEW POINT FROM HE SUPPER BLEND. HAVE USED THE MOSG25 FOR SUSTAINED WIND SPEED. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... HIGH PRESSURE IS EXPECTED TO WEAKEN AND CREST THEN CREST OVER THE REGION WEDNESDAY NIGHT. A WARM FRONT IS EXPECTED TO APPROACH FROM THE SOUTH WEST THURSDAY AND FRIDAY THEN MOVE ACROSS THE STATE SATURDAY. A COLD FRONT WILL THEN FOLLOW AS INTENSE LOW PRESSURE MOVES ACROSS CENTRAL CANADA. WILL USE HE SUPPER BLEND TO POPULATE ALL GRIDS. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... NEAR TERM: VFR GOING TO MVFR AFTER 06Z W/THE POTENTIAL FOR IFR ACROSS KBGR AND KBHB SUNDAY MORNING AND THE IFR EDGING INTO THE NORTHERN TERMINALS BY SUNDAY AFTERNOON. SOME IMPROVEMENT TO MVFR FOR KBGR AND KBHB AND EVEN VFR AS THIS REGION GETS ON THE SOUTH SIDE OF THE LOW AS SW FLOW SETS UP. SHORT TERM: IFR CONDITIONS ARE EXPECTED SUNDAY NIGHT THEN IMPROVING TO VFR CONDITIONS MONDAY. MVFR CONDITIONS EXPECTED TUESDAY. VFR CONDITIONS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM: NO HEADLINES ANTICIPATED THROUGH SUNDAY. THERE IS A SSW SWELL ATTM ON THE WATERS W/WAVE HEIGHTS OF 3-4 FT. EXPECT THIS SWELL TO CONTINUE INTO SUNDAY. A 30KT LLVL JET FROM 925-850MBS IS FORECAST TO MOVE ACROSS THE WATERS LATER TONIGHT INTO EARLY SUNDAY. THIS WILL BRING THE WINDS UP A BIT W/GUST TO 20 KTS ESPECIALLY OVER THE OUTER WATERS. SHORT TERM: FOR SUSTAINED WINDS WILL USE A BLEND OF THE SREF AND GFS40 THEN TRANSITION TO THE SUPPER BLEND LATE TUESDAY. FOR WAVES: WILL USE THE SWAN/NAM OUT TO 0000Z TUESDAY THEN TRANSITION TO THE WNA/4. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...KHW/HEWITT SHORT TERM...MIGNONE LONG TERM...MIGNONE AVIATION...KHW MARINE...KHW/HEWITT/MIGNONE
AREA FORECAST DISCUSSION
NWS CARIBOU ME
600 AM EDT FRI MAY 2 2014 .SYNOPSIS... AN UNSETTLED WEATHER PATTERN WILL PERSIST THROUGH THE WEEKEND INTO EARLY NEXT WEEK WHILE SEVERAL LOWS CROSS THE REGION. && .NEAR TERM /THROUGH TONIGHT/... 6AM UPDATE... ADDED ISOLATED THUNDERSTORMS FOR A WIDE SWATH OF THE FORECAST AREA THAT EXCLUDES THE CROWN OF MAINE AND DOWN EAST COASTAL AREAS. USING RAP CAPE VALUES...THERE IS JUST ENOUGH CAPE ABOVE -20C TO JUSTIFY INCLUSION OF THE THUNDERSTORMS. THE UPPER TROUGH IS QUITE SHARP AND SHOULD GENERATE STRONG LIFT LATER THIS AFTERNOON INTO EARLY EVENING. THIS PRECIPITATION WILL ALSO ENHANCE POTENTIAL FOR SHALLOW FOG TONIGHT. OTHERWISE...MADE TWEAKS TO FORECAST FOR THE FOG THAT WILL BE RETREATING IN THE NEXT FEW HOURS THIS MORNING AS WELL AS THE PRECIP CURRENTLY MOVING THROUGH DOWN EAST WITH THE SURFACE TROUGH. PREVIOUS DISCUSSION... AN OCCLUDED FRONT LIES TO THE NORTH OF THE AREA AND HAS BROUGHT THE WARMEST AIR MASS OF THE YEAR INTO THE AREA. HIGHS TODAY WILL REACH THE LOW TO MID 60S FOR MOST AREAS WITH FOG BURNING OFF EARLY THIS MORNING AND GIVING WAY TO SUNSHINE. CLOUDS INCREASE THIS AFTERNOON WITH SHOWERS DEVELOPING IN ASSOCIATION WITH AN UPPER TROUGH. ALL GUIDANCE SHOWS VERY MARGINAL SURFACE-BASED CAPE OF PERHAPS 200 J/KG AND LOW CLOUD TOPS. AS A RESULT...HAVE NOT ADDED MENTION OF ANY THUNDERSTORMS TO THE FORECAST. HOWEVER...WITH -20C BEING SO LOW IN THE ATMOSPHERE...CANNOT RULE OUT ONE OR TWO LIGHTNING STRIKES. THE BEST CHANCE WOULD SEEM TO BE SOUTH OF A LINE FROM HOULTON TO MILLINOCKET...AND NORTH OF A LINE FROM BANGOR TO CALAIS. CLOUDS WILL QUICKLY DIMINISH THIS EVENING EXCEPT IN THE CROWN OF MAINE. LOWS WILL DIP TO THE UPPER 30S TO LOW 40S WITH LIGHT WINDS. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... A DEEP UPPER LOW NEAR LAKE WINNIPEG AS 12Z SAT WILL TRACK INTO NORTHERN NEW ENGLAND BY 00Z MON. AS THE LOW ADVANCES TOWARD THE REGION SAT ANY BREAKS IN THE CLOUDS IN THE MORNING WILL GIVE WAY TO INCREASING CLOUDS ALONG WITH THE CHANCE OF A COUPLE OF SHOWERS...MAINLY ACROSS WESTERN AND NORTHERN MAINE. WET WEATHER IS EXPECTED SAT NIGHT AND ESPECIALLY SO DURING THE DAY SUNDAY AS THE UPPER LOW AND SFC LOW TRACK ACROSS THE REGION. TEMPS ARE EXPECTED TO BE NEAR SEASONABLE LEVELS SATURDAY AND WILL BE BELOW NORMAL SUNDAY WITH THE THICKER CLOUD COVER AND RAIN. THE QPF IS EXPECTED TO BE ON THE ORDER OF A THIRD OF AN INCH TO THREE QUARTERS OF AN INCH FROM SAT NIGHT THROUGH SUN AND SHOULD HAVE MINIMAL HYDROLOGICAL IMPACTS. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... THE LOW SLOWLY MOVES EAST OF THE AREA AND ACROSS THE MARITIMES EARLY NEXT WEEK. THIS WILL KEEP THE REGION IN A COOL/CYCLONIC FLOW ALOFT WITH A FEW SHOWERS...ESPECIALLY SO DURING THE HEATING OF THE DAY AS THE ATMOSPHERE DESTABILIZES. THE CHANCE OF SHOWERS MAY CONTINUE THROUGH THE MIDDLE OF THE WEEK. TEMPERATURES ARE EXPECTED TO AVERAGE A BIT BELOW NORMAL EARLY NEXT WEEK AND RETURN TO NEAR SEASONABLE LEVELS BY THE MIDDLE OF THE WEEK. THERE ARE CERTAINLY NO SIGNS OF ANY SIGNIFICANT WARM-UPS OVER THE NEXT WEEK. && .AVIATION /10Z FRIDAY THROUGH TUESDAY/... NEAR TERM: LIFR IN FOG WILL MOVE OUT THIS MORNING...LEAVING BHB LAST BY MID-MORNING. THE FOG WILL BE REPLACED BY VFR CONDITIONS. AN ISOLATED THUNDERSTORM IS POSSIBLE THIS AFTERNOON. PREVAILING VFR IS EXPECTED TONIGHT. SHORT TERM: A PERIOD OF VFR OR AT LEAST HIGH END MVFR SAT WILL GIVE WAY TO IFR IN RAIN AND PATCHY FOG LATER SAT NIGHT INTO SUN. MOSTLY MVFR EARLY NEXT WEEK AT THE NORTHERN TAF SITES AND MVFR/VFR AT AT THE DOWNEAST TERMINALS. && .MARINE... NEAR TERM: HAVE CANCELLED THE SCA FOR HAZARDOUS SEAS AND DO NOT ANTICIPATE ANY SIGNIFICANT WINDS OR SEAS THROUGH THE PERIOD. FOG WILL GRADUALLY MOVE OUT TODAY. SHORT TERM: THE WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SCA CONDITIONS THROUGH SAT NIGHT. A SLY FETCH AHEAD OF THE INCOMING LOW MAY CAUSE THE SEAS TO BUILD TO AOA 5FT SUNDAY AND A SCA IS POSSIBLE. A SCA WILL LIKELY BE REQUIRED EARLY NEXT WEEK AS LOW PRES PULLS AWAY FROM THE WATERS AND WLY FLOW INCREASES WITH GUSTS IN EXCESS OF 25 KNOTS LIKELY. && .CLIMATE... THE APRIL 2014 CLIMATE SUMMARY FOR NORTHERN AND EASTERN MAINE HAS BEEN ISSUED. PLEASE REFER TO PWMCLMCAR OR CXUS51 KCAR. THE SUMMARY IS ALSO AVAILABLE ON THE TOP NEWS STORY ON OUR WEB PAGE AT: HTTP:/WEATHER.GOV/CAR && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...MCW SHORT TERM...CB LONG TERM...CB AVIATION...MCW/CB MARINE...MCW/CB CLIMATE...CB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
400 PM CDT FRI MAY 2 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 355 PM CDT FRI MAY 2 2014 AFTERNOON SATELLITE IMAGERY SHOWING ABUNDANT CLOUD COVER ACROSS THE EASTERN HALF OF THE FA...WHILE WESTERN MINNESOTA WAS DRYING OUT UNDER PARTY CLOUDY SKIES. AN UPPER LEVEL SHORTWAVE OVERHEAD THIS AFTERNOON...QUICKLY MOVED IN TO ONLY ALLOW A SHORT TEASE OF BLUE SKIES BETWEEN THE RESIDUAL CLOUD COVER FROM THE LOW THAT HAD STALLED OVER THE AREA EARLY THIS WEEK...AND THE CLOUD COVER AND SCATTERED SHOWERS PRODUCED BY A DECENT PV ANOMALY MOVING ACROSS THE UPPER MIDWEST. A SURFACE LOW WAS LOCATED IN CENTRAL MINNESOTA...AND WILL CONTINUE MOVING ESE TONIGHT. STRONG WINDS ON THE BACKSIDE WILL CONTINUE THROUGH THE AFTERNOON AND DIMINISH THIS EVENING. THERE MAY BE ADDITIONAL SHOWER DEVELOPMENT IN THE STRATOCU DECK THIS AFTERNOON...WITH A CLAP OF THUNDER NOT OUT OF THE QUESTION. WESTERN WISCONSIN IS THE BEST BET TO FIND RAIN THIS AFTERNOON AND EVENING. THE CLEARING TREND IN WESTERN MINNESOTA WILL CONTINUE TOWARD THE EAST AS THE ABOVE MENTIONED STRATOCU DECK SLIDES EAST WITH THE UPPER TROUGH...AS TONIGHT SHOULD BE PARTLY CLOUDY ACROSS THE FA /LATER IN WISCONSIN/. A STRONG UPPER LOW IN CANADA WILL ROTATE ANOTHER PV ANOMALY TOWARD OUR AREA IN NORTHWEST FLOW TOMORROW...WHICH WILL SPREAD MID LEVEL CLOUDS BACK IN TO MUCH OF MINNESOTA AND WISCONSIN. KEPT A SLIGHT CHANCE OF PRECIPITATION IN THE FORECAST ALONG THE NORTHERN PERIPHERY OF THE CWA...FROM NORTH OF ST. CLOUD...THROUGH THE MILLE LACS LAKE AREA...AND TOWARD CHIPPEWA FALLS WISCONSIN. OUR AREA IS SIMPLY SOUTH OF THE BEST LIFT...AND LOW LEVEL DRY AIR WILL ONLY HAMPER THE CHANCES OF LIGHT RAIN REACHING THE SURFACE. OTHERWISE...DEEP MIXING WILL OCCUR TOMORROW AND BREEZY CONDITIONS WILL RESULT...AND TEMPERATURES REMAIN ON TRACK TO BE ABOUT 10 DEGREES BELOW NORMAL ACROSS THE BOARD. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 355 PM CDT FRI MAY 2 2014 A NORTH AMERICAN PROJECTION OF THE WATER VAPOR AND GFS 500MB HEIGHTS IDENTIFIED NORTHWEST FLOW ACROSS THE MIDWEST...WITH TWO LARGE UPPER LEVEL LOWS IN THE EASTERN PACIFIC. OVER THE NEXT COUPLE OF DAYS THE EASTERN MOST UPPER LEVEL LOW WILL SEND A SERIES OF SHORTWAVES ACROSS THE ROCKIES...WHICH WILL CAUSE THE FLOW TO BECOME MORE ZONAL BY EARLY NEXT WEEK. ONE OF THESE SHORTWAVES WILL GENERATE SHOWERS AND PERHAPS A THUNDERSTORM ON SUNDAY. AT THIS TIME IT LOOKS LIKE THE BEST CHANCE FOR PRECIP WILL BE ALONG AND SOUTH OF THE MINNESOTA RIVER VALLEY WHERE THE LOW LEVEL THERMAL GRADIENT WILL SET UP AND CORRESPONDING H850-700MB FGEN. GIVEN THE STRONG FORCING...HAVE INCLUDED ISOLATED THUNDER SINCE THERE IS SOME UPPER LEVEL CAPE...BUT THE THREAT FOR SEVERE WEATHER IS VIRTUALLY NON EXISTENT. BY THE MIDDLE OF NEXT WEEK...A TROUGH WILL CARVE OUT ACROSS THE DESERT SOUTHWEST WHICH WILL LEAD TO SOUTHWEST FLOW...GULF MOISTURE...AND WARMER AIR OVER THE UPPER MIDWEST. CONFIDENCE IS HIGH THAT PRECIP WILL OCCUR WITHIN THE WED/THU TIMEFRAME AS THE WARM FRONT LIFTS NORTHWARD. THE CHALLENGE IS TRYING TO TIME THE PRECIP IN THE 12HR GRIDS. AS OF NOW HAVE HIGHLIGHTED WEDNESDAY NIGHT TO THURSDAY MORNING AS THE BEST CHANCE FOR RAIN WITH THE LOW LEVEL JET AND THETA_E ADVECTION SPREADING OVERHEAD DURING THAT TIME PERIOD. SEVERE WEATHER WILL BE POSSIBLE WITH FAVORABLE DEEP LAYER SHEAR...AND ELEVATED INSTABILITY. THE POTENTIAL FOR SURFACE BASED STORMS DEPENDS ON THE TIMING AND PLACEMENT OF THE SURFACE LOW. THE GFS/ECMWF/GEM 02.12 ARE IN SOME DISAGREEMENT...WITH THE GFS FARTHER WEST AND STRONGER THAN THE ECMWF...WHILE THE GEM IS SIMILAR TO THE GFS IN LOCATION...ONLY LAGGING ABOUT 6HRS BEHIND. FOR NOW WILL JUST GENERALIZE THE WEATHER TYPE WITH THUNDERSTORMS...BUT IF THINGS COME TOGETHER THE POTENTIAL IS THERE FORE A FEW STRONG TO SEVERE STORMS CENTERED AROUND THE THURSDAY TIMEFRAME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 100 PM CDT FRI MAY 2 2014 A FEW ISSUES TODAY...THE WIND SHIFT MOVING THROUGH THE FA NOW AND THE WIND SPEEDS BEHIND IT...AND THE STRATO CU DEVELPOMENT ACROSS SOUTHERN MINNESOTA. CU RULE VERY NEGATIVE TODAY...AND RAP SHOWING SOLID 850 MOISTURE TO SUPPORT WIDESPREAD CLOUD COVER. THE ISSUE THOUGH IS THE HEIGHT OF THESE CLOUDS...AS THEY LOOK TO STRADDLE THE DIFFERNCE BETWEEN MVFR AND VFR CONDITIONS. COLD AIR ADVECTION IS NOT IMPRESSIVE...SO MAY STAY VFR ALL AFTERNOON AT MANY LOCATIONS. SOUTH WINDS ACROSS FAR EASTERN MINNESOTA AND IN WISCONSIN WILL GRADUALLY SHIFT TOWARD THE NW THROUGH THE AFTERNOON. DECENT GUSTS ARE EXPECTED TO DEVELOP IN THIS AREA...AROUND 20-25KTS. STRONGER GUSTS WILL CONTINUE ACROSS WESTERN MINNESOTA WHERE 30+ KTS HAS ALREADY BEEN OBSERVED. SCATTERED SHOWERS AND A CLAP OF THUNDER IS POSSIBLE THIS AFTERNOON/EARLY EVENING. KMSP...ANY MVFR THIS AFTERNOON WILL BE BRIEF AS CEILING HEIGHTS GRADUALLY LIFT. WINDS ARE IN THE PROCESS OF TURNING WESTERLY AND INCREASING. KEPT -SHRA IN THE FORECAST TO ACCOUNT FOR THE POSSIBILITY OF SCATTERED SHOWERS ACROSS THE AREA. /OUTLOOK FOR KMSP/ SAT...VFR. NW WINDS 15G22 KTS. SUN...VFR. NW WINDS 5 KTS BECOMING NE. MON...VFR. SLIGHT CHANCE -SHRA. E WINDS 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...SPD LONG TERM...JRB AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
145 PM CDT FRI MAY 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM CDT FRI MAY 2 2014 DEEP LOW THAT HAS BEEN INFLUENCING OUR WEATHER SINCE SATURDAY IS STARTING TO FINALLY LOSE ITS GRIP ON THE REGION AS A SFC RIDGE AXIS HAS WORKED IN FROM THE WEST. THE GOOD NEWS IS THAT BEHIND THIS RIDGE AXIS...SKIES HAVE CLEARED OUT WITH WITH DEVELOPMENT OF SW WINDS. THE BAD NEWS...SAID CLEARING IS QUICKLY BEING GOBBLED UP BY INCREASING MID/UPPER CLOUDS IN ASSOCIATION WITH A POTENT NORTHWEST FLOW WAVE THAT WAS QUICKLY APPROACHING NW MN THIS MORNING. IN FACT...THIS IS NOT THE ONLY WAVE THAT WILL POTENTIALLY IMPACT THE AREA DURING THE SHORT TERM...AS ANOTHER...MORE POTENT WAVE OVER NRN SASKATCHEWAN WILL HELP SEND A SECONDARY COLD FRONT ANS SHOWER CHANCE TOWARD CENTRAL MN LATE TONIGHT. THE WAVE NEAR WINNIPEG HAS A GOOD REFLECTION ON WV/IR SATELLITE IMAGERY...BUT IS BATTLING DRY AIR AND SUBSIDENCE IN THE WAKE OF THE SYSTEM THAT WAS SLOWLY WORKING INTO NW QUEBEC. THIS HAS MEANT NOT MUCH IN THE WAY OF PRECIP HAS BEEN REACHING THE GROUND THIS MORNING...BUT THAT IS EXPECTED TO CHANGE BY THE AFTERNOON. THE ADDITION OF DIURNAL HEATING WITH THE COOL TEMPERATURES ALOFT WILL ALLOW FOR THE DEVELOPMENT OF SOME RATHER HEALTHY SHOWERS BY THE AFTERNOON...AS SEEN WITH THE MPXWRF AND HOPWRF MEMBERS. ALSO ADDED IN AN ISO THUNDER MENTION FOR THE AFTERNOON AS HIGH-RES MODELS ARE SHOWING RATHER AGITATED RETURNS DEVELOPING IN THEIR REFLECTIVITY FORECASTS...WITH NAM BUFR SOUNDINGS SHOWING A COUPLE HUNDRED J/KG OF MUCAPE DEVELOPING AS WELL. NOT EXPECTING A LOT OF THUNDER...BUT ENOUGH INSTABILITY LOOKS TO EXIST TO GENERATE A FEW CLAPS OF THUNDER. THIS ACTIVITY IS EXPECTED TO REMAIN MAINLY EAST OF THE MISSISSIPPI RIVER...AS THE MID LEVEL DRY SLOT LOOKS TO KEEP AREAS WEST OF THE MISS DRY. BESIDE THE PRECIP...WAA OUT AHEAD OF THIS FIRST WAVE WILL SEND H85 TEMPS UP TO AROUND +4 IN SW MN. THIS COMBINED WITH MORE ABUNDANT SUNSHINE WILL BE ENOUGH TO ALLOW AREAS ALONG AND SW OF A MORRIS TO ALBERT LEA LINE TO REACH THE 60 DEGREE MARK. HOWEVER...THESE WARMER TEMPERATURES WILL BE OFFSET SOME BY THE DEVELOPMENT OF BREEZY NW WINDS BY THE AFTERNOON IN THE WAKE OF THE COLD FRONT... WITH GUSTS AOA 30 MPH LIKELY OUT IN THE WIND FAVORED AREAS OF WRN/SRN MN. THIS EVENING...WILL LIKELY SEE SKIES CLEAR OUT FOR A BIT BEHIND THIS FIRST WAVE...BUT THE ARRIVAL OF THE NEXT WAVE BY THE END OF THE PERIOD WILL RESULT IN THE QUICK RETURN OF CLOUD COVER. THIS SECOND WAVE LOOKS TO HAVE EVEN LESS MOISTURE TO WORK WITH THAN THE ONE FOR TODAY...SO EXPECTING EVEN LESS PRECIP WITH IT. STILL...HI- RES CAMS ALONG WITH MOST DETERMINISTIC MODELS DO SHOW THE NEXT POTENTIAL BOUT OF SHOWERS WORKING INTO CENTRAL MN BY 12Z SAT...SO HAVE A LITTLE CHANCE OF 20 POPS TO ACCOUNT FOR THAT WITH BETTER PRECIP COVERAGE EXPECTED TO THE NORTH. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 420 AM CDT FRI MAY 2 2014 SATURDAY THROUGH MONDAY...THE FIRST PART OF THE EXTENDED FORECAST LOOKS RATHER BENIGN AS NW FLOW ALOFT TRANSITIONS TO A BUILDING UPR LVL RIDGE WHILE SFC HIGH PRES IS THE DOMINANT SFC FEATURE. AN UPR LVL RIDGE THAT WAS QUASI-STNRY OVER THE WRN CONUS WILL GRADUALLY SHIFT INTO THE CENTRAL CONUS OVER THE WEEKEND...KEEPING THE WARMER HIGHS OF 50S TO LWR 60S IN PLACE INTO EARLY NEXT WEEK. THE WARMING TREND OVER THE WEEKEND IS NOT AS IMPRESSIVE AS WHAT PRIOR MODEL RUNS HAD SHOWN...DUE TO THE RIDGE BREAKING DOWN SOMEWHAT AS IT MOVES INTO THE CENTRAL STATES. THIS BREAKDOWN IN THE RIDGE WILL ALSO IMPACT THE POTENTIAL FOR PRECIP...OR MORE TO THE POINT... THE POTENTIAL FOR SOLID DRY TIME THROUGHOUT THE WEEKEND INTO EARLY NEXT WEEK. SFC HIGH PRES NUDGING INTO THIS REGION FROM WRN CANADA WILL SLOWLY RETREAT NWD...LEAVING A TRANSITION ZONE IN PLACE BETWEEN LOW PRES TO THE SW AND HIGH PRES TO THE N. SEVERAL WEAK UPR LVL DISTURBANCES RIDING THE PERIPHERY OF THE UPR LVL RIDGE WITHIN FAIRLY DEEP MOISTURE MAY BE ENOUGH TO PRODUCE ISOLD TO SCTD SHWRS FROM TIME TO TIME OVER THE AREA...WITH THE MOST PRONOUNCED OF WHICH DRIVING SWWD FROM SAT NIGHT INTO SUN MRNG OVER SWRN AND SRN MN. HAVE KEPT POPS FOR THIS FEATURE IN THE CHC CATEGORY DUE TO THE SPEED OF THE PV ANOMALY ASSOCIATED WITH THIS WAVE AND HIGHLY VARIABLE SOLUTIONS WITH RESPECT TO COVERAGE. HIGH PRES LOOKS TO BETTER RE-ASSERT ITSELF MON NIGHT OVER THE GRT LKS...XTNDG WWD INTO MN...THUS HAVE BEEN ABLE TO SHOW A DRY FCST FOR MON NIGHT. TUESDAY THROUGH THURSDAY...A MORE ACTIVE PATTERN LOOKS TO BE THE CASE DURG THE MIDDLE PORTION OF NEXT WEEK AS A LONGWAVE TROF DRIVING SWD FROM THE GULF OF ALASKA DOWN THE WRN NOAM COAST MOVES ONSHORE THE CALI COAST SAT-TUE. AS IT MOVES OVER THE SWRN STATES TUE AND TUE NIGHT...IT WILL PICK UP A DEVELOPING LOW PRES CENTER OVER THE FAVORED CO/KS CYCLOGENESIS REGION AND SLOWLY SHIFT IT ENE TUE NIGHT THRU THU. WHAT IS DIFFICULT TO DETERMINE ATTM IS THE TRACK AND SPEED OF ITS PROGRESSION. THERE ARE SIGNIFICANT MODEL DISCREPANCIES IN THESE ASPECTS...WHICH WOULD GREATLY IMPACT THE TSTM...AND POSSIBLE SEVERE WX...DISTRIBUTION FOR THE CENTRAL STATES BY MIDWEEK. ATTM...MORE CONFIDENCE IS BEING SHOWN IN KEEPING THE LOW PRES TRACK S OF MN/WI...OVER MORE OF A KS-NE-IA-IL TRACK. THIS WOULD KEEP GREATER ISENTROPIC LIFT AND MORE WIDESPREAD MOISTURE OVER THE AREA WITH COOLER TEMPERATURES...WHILE GREATER INSTABILITY WITH WARMER TEMPERATURES AND STRONGER DYNAMIC FEATURES WOULD BE S OF THIS REGION. THUS...TSTMS CANNOT BE RULED OUT...BUT THE SRN TRACK DOES GIVE RISE TO ADDITIONAL HIGH RAINFALL AMOUNTS. SO...HAVE BEEN ABLE TO RAISE POPS TO 50-60 PERCENT FOR MUCH OF THE AREA WED INTO THU SINCE CONFIDENCE IS GREATER THAT THERE WILL BE SHWRS/TSTMS BUT IT BECOMES A MATTER OF DETERMINING THE STORM STRENGTH WHICH WILL COME AS MODEL AGREEMENT INCREASES WITH THE LOW PRES TRACK. HAVE ALSO SLIGHTLY NUDGED UP TEMPS IN THE TUE-THU PERIOD...ESP OVER SRN MN WHICH WILL LIKELY EXPERIENCE HIGHS HITTING THE LWR 70S WED-THU. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 100 PM CDT FRI MAY 2 2014 A FEW ISSUES TODAY...THE WIND SHIFT MOVING THROUGH THE FA NOW AND THE WIND SPEEDS BEHIND IT...AND THE STRATO CU DEVELPOMENT ACROSS SOUTHERN MINNESOTA. CU RULE VERY NEGATIVE TODAY...AND RAP SHOWING SOLID 850 MOISTURE TO SUPPORT WIDESPREAD CLOUD COVER. THE ISSUE THOUGH IS THE HEIGHT OF THESE CLOUDS...AS THEY LOOK TO STRADDLE THE DIFFERNCE BETWEEN MVFR AND VFR CONDITIONS. COLD AIR ADVECTION IS NOT IMPRESSIVE...SO MAY STAY VFR ALL AFTERNOON AT MANY LOCATIONS. SOUTH WINDS ACROSS FAR EASTERN MINNESOTA AND IN WISCONSIN WILL GRADUALLY SHIFT TOWARD THE NW THROUGH THE AFTERNOON. DECENT GUSTS ARE EXPECTED TO DEVELOP IN THIS AREA...AROUND 20-25KTS. STRONGER GUSTS WILL CONTINUE ACROSS WESTERN MINNESOTA WHERE 30+ KTS HAS ALREADY BEEN OBSERVED. SCATTERED SHOWERS AND A CLAP OF THUNDER IS POSSIBLE THIS AFTERNOON/EARLY EVENING. KMSP...ANY MVFR THIS AFTERNOON WILL BE BRIEF AS CEILING HEIGHTS GRADUALLY LIFT. WINDS ARE IN THE PROCESS OF TURNING WESTERLY AND INCREASING. KEPT -SHRA IN THE FORECAST TO ACCOUNT FOR THE POSSIBILITY OF SCATTERED SHOWERS ACROSS THE AREA. /OUTLOOK FOR KMSP/ && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...JPC AVIATION...SPD
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
616 PM CDT SAT MAY 3 2014 .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 330 PM CDT SAT MAY 3 2014 THE MAIN FORECAST CONCERNS THROUGH THE SHORT TERM WILL BE TEMPERATURES...THEN SMALL PRECIPITATION CHANCES TONIGHT AND EARLY SUNDAY...LATE SUNDAY NIGHT AND ALSO TUESDAY. THIS MORNING/S UPPER AIR MAPS SHOWED A CLOSED H5 LOW PRESSURE SYSTEM APPROACHING THE PACIFIC NORTHWEST WITH 100M+ HT FALLS. A NARROW RIDGE EXTENDED FROM WESTERN MONTANA TOWARD ARIZONA. CLOSED H5 LOW PRESSURE WAS ALSO CENTERED OVER MANITOBA WITH IT/S TROF STRETCHING SOUTHEAST INTO THE GREAT LAKES AND MID ATLANTIC STATES. THIS MID LEVEL TROF HAS RESULTED IN A PUSH OF THE SURFACE FRONT TO SOUTH OF MANHATTAN KS TOWARD EMPORIA AND SOUTH OF HAYS KS. THERE WAS NORTHWEST FLOW ALOFT OVER THE PLAINS AND A RIBBON OF MOISTURE WAS NOTED AT THE MID LEVELS AND ALSO AT H85 ACROSS WESTERN SD AND WESTERN NEBRASKA. MID LEVEL WARM AIR ADVECTION AND FRONTOGENESIS ALONG WITH STEEP LAPSE RATES RESULTED IN A SMALL AREA OF SHOWERS/SPRINKLES FROM SD INTO NEBRASKA AND WESTERN IOWA. THROUGH THE SHORT TERM...THERE WILL BE THESE SUBTLE FEATURES THAT WILL BRING SOME PRECIP CHANCES TO THE AREA...HOWEVER ANY WIDESPREAD PRECIPITATION LOOKS TO HOLD OFF UNTIL LATER IN THE WEEK. WARMER AIR WILL BE LIFTING NORTHWARD LATER THIS AFTERNOON AND TONIGHT WITH STRENGTHENING H85 WINDS AND SOME MOISTURE ALONG AND NORTH OF THE H85 WARM FRONT. MEANWHILE...FRONTOGENESIS INCREASES AS WELL NEAR THE SD/NEBRASKA BORDERS. SOME OF THE SHORT RANGE HIGH RES MODELS SHOW ECHOES ALOFT IN SOUTHEAST NEBRASKA AS EARLY AS LATE THIS AFTERNOON. THE RAP AND 4KM WRF HAVE PRECIP DEVELOPING IN NORTHEAST NEBRASKA AFTER 09Z...THE NAM BETWEEN 06Z- 09...AND THE GFS BETWEEN 06Z-12Z. ALTHOUGH THERE MAY BE SOME SPRINKLES OR ISOLATED SHOWERS FARTHER SOUTH...HOWEVER DUE TO LOW CONFIDENCE...HAVE ONLY MAINTAINED ISOLATED SHOWERS AND A POSSIBLE RUMBLE OF THUNDER FOR NORTHEAST NEBRASKA BETWEEN 06Z AND 12Z. SOME OF THESE SHOWERS MAY LINGER IN THE NORTHEAST SUNDAY MORNING. SUNDAY...THE SURFACE FRONT WILL STILL BE TO THE SOUTH OF THE FORECAST AREA WITH A BRISK EAST SURFACE FLOW. THIS SHOULD HOLD TEMPERATURES IN THE 60S...WITH 70S FOR SOUTHEAST NEBRASKA. TEMPERATURES NEAR THE KS BORDER WILL NEED TO BE MONITORED DUE TO THE FRONT NEARBY. THERE IS SOME WEAK LIFT...HOWEVER MOISTURE APPEARS LIMITED...THUS HAVE LEFT DRY. SUNDAY NIGHT...ANOTHER WEAK SHORTWAVE PASS THROUGH THE NORTHWEST FLOW ALOFT AND AGAIN...THERE MAY BE ISOLATED SHOWERS...HOWEVER THE COVERAGE IS TOO LOW TO MENTION AT THIS TIME. THE FLOW ALOFT TRANSITIONS TO SOUTHWEST FLOW AND A WEAK IMPULSE COULD BRING ISOLATED SHOWERS TUESDAY. WARM MID LEVEL TEMPERATURES ARE IN PLACE AND THE CURRENT FORECAST IS DRY...HOWEVER THIS WILL NEED TO BE WATCHED AS INSTABILITY INCREASES. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 PM CDT SAT MAY 3 2014 STILL SOME SIGNIFICANT MODEL DIFFERENCES FOR TEMPERATURES WED. TRENDED WITH THE EC THAT HAS THE HOTTER TEMPERATURES ACROSS THE SOUTHERN PART OF THE FORECAST ARE COMPARED TO THE COOLER GFS. SHOWER AND THUNDERSTORM CHANCES INCREASE FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH MUCH DEEPER MOISTURE RETURNING TO THE REGION...A SURFACE FRONT IN THE AREA AND THE LONG WAVE TROF MOVING TO THE PLAINS. NUDGED RAIN CHANCES UP FOR THURSDAY/THURSDAY NIGHT.SHEAR AND INSTABILITY INCREASE...HOWEVER FRONTAL PLACEMENT FOR THURSDAY WILL BE A KEY FACTOR FOR SEVERE WEATHER POTENTIAL THURSDAY/THURSDAY NIGHT. SOME ENERGY MAY LAG AND MAY HAVE TO INCLUDE PRECIP CHANCES INTO FRIDAY...BUT FOR NOW FRI/SAT ARE DRY. && .AVIATION...(00Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 615 PM CDT SAT MAY 3 2014 VFR CONDITIONS EXPECTED THRU THE FCST PD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...DEE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1240 PM CDT FRI MAY 2 2014 .SYNOPSIS... ISSUED AT 341 AM CDT FRI MAY 2 2014 AT 08Z...A COLD FRONT WAS MOVING SOUTHEAST THROUGH NORTHWESTERN NORTH DAKOTA. ACROSS WESTERN NEBRASKA WINDS WERE LIGHT WESTERLY AT 5 MPH OR LESS. BENEATH MOSTLY CLEAR SKIES...TEMPERATURES WERE IN THE LOWER TO MID 30S...WITH THE COLDEST READING OF 27 AT LBF. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 341 AM CDT FRI MAY 2 2014 A HIGHLY AMPLIFIED H5 PATTERN EXISTS WITH A STRONG RIDGE ALONG THE WESTERN STATES WHILE A POSITIVELY TILTED TROUGH EXTENDED FROM WEST TEXAS INTO THE GREAT LAKES REGION. FOR TODAY...INCREASING CLOUDINESS WITH A WEAK COLD FRONT DROPPING SOUTH INTO THE NORTHERN PANHANDLE AND CENTRAL NEBRASKA BY LATE AFTERNOON. NOT TOO MUCH CONTRAST IN HIGHS HOWEVER RANGING FROM THE UPPER 60S AT VTN...ANW AND ONL TO 76 AT IML. NW WINDS TO RANGE FROM 10 TO 20 MPH TODAY...WHICH WILL BE LIGHTER THAN THE PAST SEVERAL DAYS. REGARDING CHANCES FOR ANY SHOWERS OR THUNDERSTORMS...HAVE TRIMMED WEST THE AREA TO MAINLY THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY THIS AFTERNOON. THE NAM AND RAP MODELS ARE SIMILAR TARGETING THESE AREAS. A DISTURBANCE TO MOVE THROUGH EASTERN WYOMING AND THE BLACK HILLS REGION EARLY THIS AFTERNOON AND SHOULD TRIGGER ISOLATED SHOWERS OR THUNDERSTORMS. THE STEEPER H7 TO H5 LAPSE RATES NEAR 7.5 C.KM WILL BE PERCENT IN THE PANHANDLE AND SW NEBR THIS AFTERNOON. A DISTURBANCE BEHIND THE COLD FRONT WILL TRIGGER SOME SHOWERS FROM EASTERN MONTANA INTO WESTERN AND CENTRAL SOUTH DAKOTA TODAY. WHILE A FEW OF THESE SHOWERS COULD MOVE INTO NORTH CENTRAL NEBRASKA THIS AFTERNOON...MODELS DO NOT SUPPORT SUFFICIENT LIFT TO INTRODUCE A MENTION. TONIGHT...CONTINUED A SLIGHT CHANCE FOR SHOWERS IN THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY...WHICH SHOULD DISSIPATE BY AROUND SUNSET. WITH A MILDER AIR MASS IN PLACE AND WEAK LOW PRESSURE...TEMPERATURES WILL RANGE FROM THE UPPER 30S FAR NORTHWEST TO THE LOWER 40S ELSEWHERE. SKIES WILL BE CLEARING IN THE WEST WITH LINGERING CLOUDINESS ACROSS THE EAST. SYNOPTICALLY...THE UPPER RIDGE IN THE WEST WILL FLATTEN OUT AS IT MOVES INTO THE GREAT BASIN WHILE A CLOSED LOW MOVES INTO MANITOBA AND WESTERN ONTARIO. THIS WILL KEEP THE COOLER AIR TO OUR NORTH ACROSS THE DAKOTAS AND GREAT LAKES. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 341 AM CDT FRI MAY 2 2014 SATURDAY WILL SEE THE LOW PUSHING ACROSS THE NE PACIFIC...HEADING FOR THE PACIFIC NW STATES. THIS WILL CAUSE THE HIGH ACROSS THE DESERT SOUTHWEST TO PUSH EAST. MEANWHILE A LEE SIDE TROUGH WILL DEVELOP. AS THE RIDGE SLIDING EAST...HEIGHTS INCREASE ACROSS THE AREA. NAM HAS BEEN THE FASTEST WITH THE HEIGHT INCREASES...WHICH HAS TRANSLATED TO MET GUIDANCE IN SW NEB INTO THE 80S. THE SLIGHTLY SLOWER GFS/EC MOS GUIDANCE HAS HELD MOST SITES ACROSS SW IN THE 70S. THE SW PART OF NEB DID SEE A QUARTER TO HALF AN INCH WITH THIS LATE APRIL EVENT...HOWEVER THE MONTH ENDED 1 TO 2 INCHES BELOW NORMAL. EXPECT THE RELATIVELY DRY SOILS TO AID IN WARMING CLOSER TO THE MET GUIDANCE NUMBERS. ALTHOUGH LATELY THE WARMEST GUIDANCE HAS BEEN THE WAY TO GO DURING THESE ABOVE NORMAL DAYS...SO MAY NEED TO TREND THIS WARMER YET. MEANWHILE A SFC HIGH WILL DIVE SOUTH INTO THE NORTHERN PLAINS. WHILE THE HIGH IS CENTERED WELL NORTH OF THE AREA...COOLER AIR IN ASSOCIATION WITH THE HIGH WILL PUSH INTO THE DAKOTAS AND PARTS OF NRN NEB. HIGHS ON SAT ACROSS THE NORTH SHOULD WARM TO AROUND 70. SATURDAY AFTERNOON STEEP LAPSE RATE DEVELOP ALONG THE LEE SIDE TROUGH. WOULD EXPECT SOME SHOWERS TO DEVELOP DURING THE PEAK HEAT...ALTHOUGH MOISTURE...DEW PTS IN THE 40S...MAY BE TOO DRY FOR ANYTHING TO REACH THE GROUND. A BETTER CHANCE...ALBEIT ONLY SLIGHTLY BETTER...WILL BE WITH A QUASI-STATIONARY BOUNDARY BETWEEN THE COOLER NORTHERN HIGH AND WARMER SW SAT EVENING. AGAIN MOISTURE IS A CONCERN AND RETAINED LOW POPS...ALTHOUGH NOT LOOKING AS GOOD AS YESTERDAY AND SCALED BACK THE COVERAGE. SUNDAY THE RIDGE CONTINUES TO ADVANCE EAST...BUT BECOMES MORE BROAD. HIGHS AGAIN INTO THE 80S ACROSS SW WITH MORE CLOUDS ACROSS THE NORTH...NEAR THE BOUNDARY...AND HIGHS IN THE 60S. SUNDAY EVENING THE BOUNDARY LIFTS NORTH AND FORECAST AREA LOOKS DRY WITH THE ACTIVITY NORTH OF THE BORDER. BY MONDAY THE BROAD RIDGE AXIS WILL BE EAST WITH SW NEB DROPPING TO AROUND 80. MORE SUN ACROSS THE NORTH AND HIGHS SHOULD BE ABLE TO WARM ABOVE SUNDAY READINGS...CLOSER TO 70. TUESDAY THROUGH THE THURSDAY A MORE ACTIVE PATTER IS SETTING UP. THE NORTHEAST PACIFIC LOW WILL OPEN INTO A TROUGH AS IT DIGS INTO THE 4 CORNERS REGION. THE GFS CONTINUES TO THEN EJECT THE LOW ONTO THE CENTRAL PLAINS. THE ECMWF BREAKS UP THE LOW WITH A PIECE PUSHING ONTO THE PLAINS WITH A SECONDARY LOW DEVELOPING OFF THE COAST OF BAJA. EITHER WAY BOTH MODELS SUPPORT A CHANCE FOR PRECIPITATION ACROSS THE AREA. THE GULF DOES OPEN UP...HOWEVER THIS IS SHORT LIVED WITH A COLD FRONT TO PUSH ACROSS THE AREA AND KEEP THE BULK OF THE MOISTURE SOUTH AND EAST OF THE AREA. TEMPS COOL INTO THE 60S AND 70S...AND WILL CONTINUE TO MONITOR THE MOISTURE PUSH NORTHWARD WHICH WILL EFFECT THE QPF AMOUNTS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1236 PM CDT FRI MAY 2 2014 VFR CONDITIONS EXPECTED ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THROUGH THE NEXT 24 HOURS. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE IN THE EASTERN PANHANDLE TOWARD LATE AFTERNOON AND EARLY EVENING...HOWEVER THE ACTIVITY SHOULD BE WIDELY SCATTERED WITH CIGS AOA 5 KFT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...ROBERG SHORT TERM...ROBERG LONG TERM...MASEK AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
643 AM CDT FRI MAY 2 2014 .SYNOPSIS... ISSUED AT 341 AM CDT FRI MAY 2 2014 AT 08Z...A COLD FRONT WAS MOVING SOUTHEAST THROUGH NORTHWESTERN NORTH DAKOTA. ACROSS WESTERN NEBRASKA WINDS WERE LIGHT WESTERLY AT 5 MPH OR LESS. BENEATH MOSTLY CLEAR SKIES...TEMPERATURES WERE IN THE LOWER TO MID 30S...WITH THE COLDEST READING OF 27 AT LBF. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 341 AM CDT FRI MAY 2 2014 A HIGHLY AMPLIFIED H5 PATTERN EXISTS WITH A STRONG RIDGE ALONG THE WESTERN STATES WHILE A POSITIVELY TILTED TROUGH EXTENDED FROM WEST TEXAS INTO THE GREAT LAKES REGION. FOR TODAY...INCREASING CLOUDINESS WITH A WEAK COLD FRONT DROPPING SOUTH INTO THE NORTHERN PANHANDLE AND CENTRAL NEBRASKA BY LATE AFTERNOON. NOT TOO MUCH CONTRAST IN HIGHS HOWEVER RANGING FROM THE UPPER 60S AT VTN...ANW AND ONL TO 76 AT IML. NW WINDS TO RANGE FROM 10 TO 20 MPH TODAY...WHICH WILL BE LIGHTER THAN THE PAST SEVERAL DAYS. REGARDING CHANCES FOR ANY SHOWERS OR THUNDERSTORMS...HAVE TRIMMED WEST THE AREA TO MAINLY THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY THIS AFTERNOON. THE NAM AND RAP MODELS ARE SIMILAR TARGETING THESE AREAS. A DISTURBANCE TO MOVE THROUGH EASTERN WYOMING AND THE BLACK HILLS REGION EARLY THIS AFTERNOON AND SHOULD TRIGGER ISOLATED SHOWERS OR THUNDERSTORMS. THE STEEPER H7 TO H5 LAPSE RATES NEAR 7.5 C.KM WILL BE PERCENT IN THE PANHANDLE AND SW NEBR THIS AFTERNOON. A DISTURBANCE BEHIND THE COLD FRONT WILL TRIGGER SOME SHOWERS FROM EASTERN MONTANA INTO WESTERN AND CENTRAL SOUTH DAKOTA TODAY. WHILE A FEW OF THESE SHOWERS COULD MOVE INTO NORTH CENTRAL NEBRASKA THIS AFTERNOON...MODELS DO NOT SUPPORT SUFFICIENT LIFT TO INTRODUCE A MENTION. TONIGHT...CONTINUED A SLIGHT CHANCE FOR SHOWERS IN THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY...WHICH SHOULD DISSIPATE BY AROUND SUNSET. WITH A MILDER AIR MASS IN PLACE AND WEAK LOW PRESSURE...TEMPERATURES WILL RANGE FROM THE UPPER 30S FAR NORTHWEST TO THE LOWER 40S ELSEWHERE. SKIES WILL BE CLEARING IN THE WEST WITH LINGERING CLOUDINESS ACROSS THE EAST. SYNOPTICALLY...THE UPPER RIDGE IN THE WEST WILL FLATTEN OUT AS IT MOVES INTO THE GREAT BASIN WHILE A CLOSED LOW MOVES INTO MANITOBA AND WESTERN ONTARIO. THIS WILL KEEP THE COOLER AIR TO OUR NORTH ACROSS THE DAKOTAS AND GREAT LAKES. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 341 AM CDT FRI MAY 2 2014 SATURDAY WILL SEE THE LOW PUSHING ACROSS THE NE PACIFIC...HEADING FOR THE PACIFIC NW STATES. THIS WILL CAUSE THE HIGH ACROSS THE DESERT SOUTHWEST TO PUSH EAST. MEANWHILE A LEE SIDE TROUGH WILL DEVELOP. AS THE RIDGE SLIDING EAST...HEIGHTS INCREASE ACROSS THE AREA. NAM HAS BEEN THE FASTEST WITH THE HEIGHT INCREASES...WHICH HAS TRANSLATED TO MET GUIDANCE IN SW NEB INTO THE 80S. THE SLIGHTLY SLOWER GFS/EC MOS GUIDANCE HAS HELD MOST SITES ACROSS SW IN THE 70S. THE SW PART OF NEB DID SEE A QUARTER TO HALF AN INCH WITH THIS LATE APRIL EVENT...HOWEVER THE MONTH ENDED 1 TO 2 INCHES BELOW NORMAL. EXPECT THE RELATIVELY DRY SOILS TO AID IN WARMING CLOSER TO THE MET GUIDANCE NUMBERS. ALTHOUGH LATELY THE WARMEST GUIDANCE HAS BEEN THE WAY TO GO DURING THESE ABOVE NORMAL DAYS...SO MAY NEED TO TREND THIS WARMER YET. MEANWHILE A SFC HIGH WILL DIVE SOUTH INTO THE NORTHERN PLAINS. WHILE THE HIGH IS CENTERED WELL NORTH OF THE AREA...COOLER AIR IN ASSOCIATION WITH THE HIGH WILL PUSH INTO THE DAKOTAS AND PARTS OF NRN NEB. HIGHS ON SAT ACROSS THE NORTH SHOULD WARM TO AROUND 70. SATURDAY AFTERNOON STEEP LAPSE RATE DEVELOP ALONG THE LEE SIDE TROUGH. WOULD EXPECT SOME SHOWERS TO DEVELOP DURING THE PEAK HEAT...ALTHOUGH MOISTURE...DEW PTS IN THE 40S...MAY BE TOO DRY FOR ANYTHING TO REACH THE GROUND. A BETTER CHANCE...ALBEIT ONLY SLIGHTLY BETTER...WILL BE WITH A QUASI-STATIONARY BOUNDARY BETWEEN THE COOLER NORTHERN HIGH AND WARMER SW SAT EVENING. AGAIN MOISTURE IS A CONCERN AND RETAINED LOW POPS...ALTHOUGH NOT LOOKING AS GOOD AS YESTERDAY AND SCALED BACK THE COVERAGE. SUNDAY THE RIDGE CONTINUES TO ADVANCE EAST...BUT BECOMES MORE BROAD. HIGHS AGAIN INTO THE 80S ACROSS SW WITH MORE CLOUDS ACROSS THE NORTH...NEAR THE BOUNDARY...AND HIGHS IN THE 60S. SUNDAY EVENING THE BOUNDARY LIFTS NORTH AND FORECAST AREA LOOKS DRY WITH THE ACTIVITY NORTH OF THE BORDER. BY MONDAY THE BROAD RIDGE AXIS WILL BE EAST WITH SW NEB DROPPING TO AROUND 80. MORE SUN ACROSS THE NORTH AND HIGHS SHOULD BE ABLE TO WARM ABOVE SUNDAY READINGS...CLOSER TO 70. TUESDAY THROUGH THE THURSDAY A MORE ACTIVE PATTER IS SETTING UP. THE NORTHEAST PACIFIC LOW WILL OPEN INTO A TROUGH AS IT DIGS INTO THE 4 CORNERS REGION. THE GFS CONTINUES TO THEN EJECT THE LOW ONTO THE CENTRAL PLAINS. THE ECMWF BREAKS UP THE LOW WITH A PIECE PUSHING ONTO THE PLAINS WITH A SECONDARY LOW DEVELOPING OFF THE COAST OF BAJA. EITHER WAY BOTH MODELS SUPPORT A CHANCE FOR PRECIPITATION ACROSS THE AREA. THE GULF DOES OPEN UP...HOWEVER THIS IS SHORT LIVED WITH A COLD FRONT TO PUSH ACROSS THE AREA AND KEEP THE BULK OF THE MOISTURE SOUTH AND EAST OF THE AREA. TEMPS COOL INTO THE 60S AND 70S...AND WILL CONTINUE TO MONITOR THE MOISTURE PUSH NORTHWARD WHICH WILL EFFECT THE QPF AMOUNTS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 644 AM CDT FRI MAY 2 2014 CEILING AND VISIBILITY WILL BE UNLIMITED TODAY AND TONIGHT. A FRONT COMMING ACROSS NEBRASKA WILL THEN BRING ISOLATED SHOWERS OR THUNDERSTORMS TO NORTHWEST NEBRASKA...BUT THE PROBABILITY OF EITHER OCCURRING AT ANY ONE SITE IS LESS THAN 20 PERCENT. HOWEVER...CEILINGS OF 8000 FEET AGL ARE LIKELY. WIND WILL INCREASE OVER MUCH OF THE AREA BY 16Z AND BECOME 290-320 AT 13G20KT BUT WILL BECOME VARIABLE THIS EVENING AT LESS THAN 10KT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...ROBERG SHORT TERM...ROBERG LONG TERM...MASEK AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
342 AM CDT FRI MAY 2 2014 .SYNOPSIS... ISSUED AT 341 AM CDT FRI MAY 2 2014 AT 08Z...A COLD FRONT WAS MOVING SOUTHEAST THROUGH NORTHWESTERN NORTH DAKOTA. ACROSS WESTERN NEBRASKA WINDS WERE LIGHT WESTERLY AT 5 MPH OR LESS. BENEATH MOSTLY CLEAR SKIES...TEMPERATURES WERE IN THE LOWER TO MID 30S...WITH THE COLDEST READING OF 27 AT LBF. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 341 AM CDT FRI MAY 2 2014 A HIGHLY AMPLIFIED H5 PATTERN EXISTS WITH A STRONG RIDGE ALONG THE WESTERN STATES WHILE A POSITIVELY TILTED TROUGH EXTENDED FROM WEST TEXAS INTO THE GREAT LAKES REGION. FOR TODAY...INCREASING CLOUDINESS WITH A WEAK COLD FRONT DROPPING SOUTH INTO THE NORTHERN PANHANDLE AND CENTRAL NEBRASKA BY LATE AFTERNOON. NOT TOO MUCH CONTRAST IN HIGHS HOWEVER RANGING FROM THE UPPER 60S AT VTN...ANW AND ONL TO 76 AT IML. NW WINDS TO RANGE FROM 10 TO 20 MPH TODAY...WHICH WILL BE LIGHTER THAN THE PAST SEVERAL DAYS. REGARDING CHANCES FOR ANY SHOWERS OR THUNDERSTORMS...HAVE TRIMMED WEST THE AREA TO MAINLY THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY THIS AFTERNOON. THE NAM AND RAP MODELS ARE SIMILAR TARGETING THESE AREAS. A DISTURBANCE TO MOVE THROUGH EASTERN WYOMING AND THE BLACK HILLS REGION EARLY THIS AFTERNOON AND SHOULD TRIGGER ISOLATED SHOWERS OR THUNDERSTORMS. THE STEEPER H7 TO H5 LAPSE RATES NEAR 7.5 C.KM WILL BE PERCENT IN THE PANHANDLE AND SW NEBR THIS AFTERNOON. A DISTURBANCE BEHIND THE COLD FRONT WILL TRIGGER SOME SHOWERS FROM EASTERN MONTANA INTO WESTERN AND CENTRAL SOUTH DAKOTA TODAY. WHILE A FEW OF THESE SHOWERS COULD MOVE INTO NORTH CENTRAL NEBRASKA THIS AFTERNOON...MODELS DO NOT SUPPORT SUFFICIENT LIFT TO INTRODUCE A MENTION. TONIGHT...CONTINUED A SLIGHT CHANCE FOR SHOWERS IN THE EASTERN PANHANDLE AND WESTERN CHERRY COUNTY...WHICH SHOULD DISSIPATE BY AROUND SUNSET. WITH A MILDER AIR MASS IN PLACE AND WEAK LOW PRESSURE...TEMPERATURES WILL RANGE FROM THE UPPER 30S FAR NORTHWEST TO THE LOWER 40S ELSEWHERE. SKIES WILL BE CLEARING IN THE WEST WITH LINGERING CLOUDINESS ACROSS THE EAST. SYNOPTICALLY...THE UPPER RIDGE IN THE WEST WILL FLATTEN OUT AS IT MOVES INTO THE GREAT BASIN WHILE A CLOSED LOW MOVES INTO MANITOBA AND WESTERN ONTARIO. THIS WILL KEEP THE COOLER AIR TO OUR NORTH ACROSS THE DAKOTAS AND GREAT LAKES. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 341 AM CDT FRI MAY 2 2014 SATURDAY WILL SEE THE LOW PUSHING ACROSS THE NE PACIFIC...HEADING FOR THE PACIFIC NW STATES. THIS WILL CAUSE THE HIGH ACROSS THE DESERT SOUTHWEST TO PUSH EAST. MEANWHILE A LEE SIDE TROUGH WILL DEVELOP. AS THE RIDGE SLIDING EAST...HEIGHTS INCREASE ACROSS THE AREA. NAM HAS BEEN THE FASTEST WITH THE HEIGHT INCREASES...WHICH HAS TRANSLATED TO MET GUIDANCE IN SW NEB INTO THE 80S. THE SLIGHTLY SLOWER GFS/EC MOS GUIDANCE HAS HELD MOST SITES ACROSS SW IN THE 70S. THE SW PART OF NEB DID SEE A QUARTER TO HALF AN INCH WITH THIS LATE APRIL EVENT...HOWEVER THE MONTH ENDED 1 TO 2 INCHES BELOW NORMAL. EXPECT THE RELATIVELY DRY SOILS TO AID IN WARMING CLOSER TO THE MET GUIDANCE NUMBERS. ALTHOUGH LATELY THE WARMEST GUIDANCE HAS BEEN THE WAY TO GO DURING THESE ABOVE NORMAL DAYS...SO MAY NEED TO TREND THIS WARMER YET. MEANWHILE A SFC HIGH WILL DIVE SOUTH INTO THE NORTHERN PLAINS. WHILE THE HIGH IS CENTERED WELL NORTH OF THE AREA...COOLER AIR IN ASSOCIATION WITH THE HIGH WILL PUSH INTO THE DAKOTAS AND PARTS OF NRN NEB. HIGHS ON SAT ACROSS THE NORTH SHOULD WARM TO AROUND 70. SATURDAY AFTERNOON STEEP LAPSE RATE DEVELOP ALONG THE LEE SIDE TROUGH. WOULD EXPECT SOME SHOWERS TO DEVELOP DURING THE PEAK HEAT...ALTHOUGH MOISTURE...DEW PTS IN THE 40S...MAY BE TOO DRY FOR ANYTHING TO REACH THE GROUND. A BETTER CHANCE...ALBEIT ONLY SLIGHTLY BETTER...WILL BE WITH A QUASI-STATIONARY BOUNDARY BETWEEN THE COOLER NORTHERN HIGH AND WARMER SW SAT EVENING. AGAIN MOISTURE IS A CONCERN AND RETAINED LOW POPS...ALTHOUGH NOT LOOKING AS GOOD AS YESTERDAY AND SCALED BACK THE COVERAGE. SUNDAY THE RIDGE CONTINUES TO ADVANCE EAST...BUT BECOMES MORE BROAD. HIGHS AGAIN INTO THE 80S ACROSS SW WITH MORE CLOUDS ACROSS THE NORTH...NEAR THE BOUNDARY...AND HIGHS IN THE 60S. SUNDAY EVENING THE BOUNDARY LIFTS NORTH AND FORECAST AREA LOOKS DRY WITH THE ACTIVITY NORTH OF THE BORDER. BY MONDAY THE BROAD RIDGE AXIS WILL BE EAST WITH SW NEB DROPPING TO AROUND 80. MORE SUN ACROSS THE NORTH AND HIGHS SHOULD BE ABLE TO WARM ABOVE SUNDAY READINGS...CLOSER TO 70. TUESDAY THROUGH THE THURSDAY A MORE ACTIVE PATTER IS SETTING UP. THE NORTHEAST PACIFIC LOW WILL OPEN INTO A TROUGH AS IT DIGS INTO THE 4 CORNERS REGION. THE GFS CONTINUES TO THEN EJECT THE LOW ONTO THE CENTRAL PLAINS. THE ECMWF BREAKS UP THE LOW WITH A PIECE PUSHING ONTO THE PLAINS WITH A SECONDARY LOW DEVELOPING OFF THE COAST OF BAJA. EITHER WAY BOTH MODELS SUPPORT A CHANCE FOR PRECIPITATION ACROSS THE AREA. THE GULF DOES OPEN UP...HOWEVER THIS IS SHORT LIVED WITH A COLD FRONT TO PUSH ACROSS THE AREA AND KEEP THE BULK OF THE MOISTURE SOUTH AND EAST OF THE AREA. TEMPS COOL INTO THE 60S AND 70S...AND WILL CONTINUE TO MONITOR THE MOISTURE PUSH NORTHWARD WHICH WILL EFFECT THE QPF AMOUNTS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1237 AM CDT FRI MAY 2 2014 CEILING AND VISIBILITY WILL BE UNLIMITED TONIGHT AND FRIDAY MORNING. A FRONT COMING ACROSS NEBRASKA WILL THEN BRING ISOLATED SHOWERS OR THUNDERSTORMS TO CENTRAL AND NORTHERN NEBRASKA...BUT THE PROBABILITY OF EITHER OCCURRING AT ANY ONE SITE IS LESS THAN 20 PERCENT. HOWEVER...CEILINGS OF 5000-8000 FEET AGL ARE LIKELY. WIND WILL INCREASE OVER MUCH OF THE AREA BY 16Z AND BECOME 280-310 AT 12-16G17-22KT BUT WILL BECOME VARIABLE FRIDAY EVENING AT LESS THAN 10KT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...ROBERG SHORT TERM...ROBERG LONG TERM...MASEK AVIATION...ROBERG
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1058 PM EDT SAT MAY 3 2014 .SYNOPSIS... A SLOW MOVING UPPER LEVEL LOW WILL KEEP UNSETTLED WEATHER OVER THE REGION FOR THE REMAINDER OF THE WEEKEND WITH OCCASIONAL SHOWERS AND COOL TEMPERATURES. HIGH PRESSURE WILL BRING MUCH DRIER CONDITIONS FOR THE START OF NEXT WEEK ALTHOUGH TEMPERATURES WILL REMAIN BELOW AVERAGE. THE NEXT CHANCE OF RAIN WILL NOT ARRIVE UNTIL THURSDAY WHEN A WARM FRONT MOVES ACROSS THE REGION. THIS WARM FRONT WILL USHER IN A SIGNIFICANT WARMING TREND FOR THE END OF THE WEEK. && .NEAR TERM /THROUGH SUNDAY/... NEGATIVELY TILTED MID LEVEL TROUGH AXIS EXTENDS FROM CENTRAL ONTARIO PROVINCE SOUTHEAST ACROSS THE LOWER GREAT LAKES TO WESTERN NEW YORK. THIS CONTINUES TO DRIVE SCATTERED SHOWERS ACROSS WESTERN NEW YORK AND A MORE ORGANIZED BAND OF SHOWERS ACROSS EASTERN LAKE ONTARIO COUNTIES. WITHOUT DAYTIME HEATING THESE SHOWERS HAVE LOST THEIR EARLIER CONVECTIVE STRUCTURES ALTHOUGH SOME GUSTY WINDS MAY ACCOMPANY THE BAND OF SHOWERS EAST OF LAKE ONTARIO. THROUGH THE REMAINDER OF THE OVERNIGHT EXPECT THE TROUGH AXIS TO SHIFT EAST OF WNY WITH BOTH SPC SSEO AND HRRR MESOSCALE MODELS SHOW SHOWER ACTIVITY ENDING ACROSS WNY BEFORE 06Z. COOL AND MOIST UPSLOPE FLOW OVER THE TUG HILL HOWEVER WILL KEEP LINGERING SCATTERED SHOWERS EAST OF LAKE ONTARIO BEHIND THE PRESENT BAND. EARLY SUNDAY MORNING MODELS SHOW A SUBTLE SHORTWAVE CROSSING LAKE ERIE WHICH COULD BRING ANOTHER CHANCE OF SHOWERS ACROSS MAINLY THE SOUTHERN TIER. A LINGERING SURFACE PRESSURE GRADIENT WILL KEEP BREEZY WINDS IN PLACE OVERNIGHT. THIS COMBINED WITH LINGERING OVERCAST SKIES WILL KEEP TEMPS FROM DROPPING BELOW 40 EXCEPT ACROSS THE INTERIOR SOUTHERN TIER. ON SUNDAY THE CORE OF THE MID LEVEL LOW WILL SWING QUICKLY ACROSS NORTHERN NEW ENGLAND AND DEEPEN WITH TIME...ALLOWING A NOTABLE AREA OF CHANNELLED VORTICITY TO SWEEP SOUTH ACROSS THE LOWER LAKES REGION. A SURFACE LOW WILL ALSO DEEPEN OVER NORTHERN NEW ENGLAND WITH A TRAILING SURFACE TROUGH CROSSING THE NORTH COUNTRY DURING THE AFTERNOON. THE COMBINATION OF FORCING ALOFT AND LOW LEVEL CONVERGENCE WILL CONTINUE TO SUPPORT THE RISK OF SHOWERS. THE MOST WIDESPREAD COVERAGE IS EXPECTED ACROSS THE EASTERN LAKE ONTARIO REGION IN CLOSER PROXIMITY TO DEEPER MOISTURE AND STRONGER ASCENT. SCATTERED SHOWERS ARE ALSO LIKELY PER 03/12Z SPC SSEO ACROSS WESTERN NEW YORK MAINLY DURING THE AFTERNOON. VERY COOL TEMPERATURES WILL CONTINUE WITH HIGHS ON THE LAKE PLAINS ONLY IN THE LOWER TO MID 50S AT BEST...WITH MID TO UPPER 40S ACROSS THE HIGHER TERRAIN AND ALONG THE IMMEDIATE LAKESHORES. WINDS WILL ALSO INCREASE NOTABLY...WITH GUSTS OF 30-35 MPH BECOMING COMMON ACROSS THE ENTIRE REGION WITH SOME 40 MPH GUSTS LIKELY ALONG AND DOWNWIND OF THE LAKE ONTARIO SHORE. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... SUNDAY NIGHT THE LAST OF THE SHOWERS WILL BE PASSING OVER OUR REGION FROM THE GENESEE VALLEY EASTWARD. THE UPPER LEVEL LOW THAT HAS BEEN RESPONSIBLE FOR THESE WEEKEND SHOWERS WILL NOW BE MOVING EASTWARD ACROSS NEW ENGLAND. SHOWERS WILL SLOWLY END THROUGH THE NIGHT AND EARLY MONDAY FROM THE GENESEE VALLEY EASTWARD...WITH SHOWERS LINGERING THE LONGEST OVER THE TUG HILL REGION. A COOL NORTHWEST UPSLOPE FLOW BEHIND THE CLOSED UPPER LEVEL LOW MAY LINGER CLOUDS THROUGH THE NIGHT. WHERE CLEARING...AND DIMINISHING WINDS DO OCCUR SUNDAY NIGHT FROST CONCERNS WILL BE PRESENT ACROSS WNY. FOR MONDAY AND TUESDAY CANADIAN HIGH PRESSURE WILL BUILD TOWARDS THE REGION FROM THE UPPER GREAT LAKES. THIS FEATURE WILL PROVIDE INCREASING AMOUNTS OF SUNSHINE...THOUGH WITH A LINGERING COOL AIRMASS OVERHEAD OUR AFTERNOON HIGHS WILL STILL BE BELOW NORMAL...WITH WIDESPREAD MID AND UPPER 50S. WITH THE COOL AIRMASS AND MORE CERTAINTY OF CLEAR SKIES OVERNIGHT MONDAY NIGHT FROST WILL BE MORE LIKELY ACROSS ZONES WHERE THE FROST/FREEZE PROGRAM HAS BEGUN. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... TO START THIS TIME PERIOD ON WEDNESDAY AN OPEN WAVE UPPER LEVEL DISTURBANCE WILL BE PASSING THROUGH THE GREAT BASIN...WITH A DOWNSTREAM RIDGE OVER THE TENNESSEE VALLEY AND EXTENDING NORTHWARD TOWARDS THE CENTRAL GREAT LAKES. FOR WEDNESDAY WE SHOULD HAVE A NEAR NORMAL DAY IN THE TEMPERATURE DEPARTMENT WITH MORNING SUNSHINE STARTING TO FADE BEHIND INCREASING CIRRUS FROM THE SOUTHWEST. THESE CLOUDS WILL BE IN ADVANCE OF A WARM FRONT...ONE THAT WILL LIFT ACROSS THE REGION WEDNESDAY NIGHT AND THURSDAY. RAIN SHOWERS...AND EMBEDDED THUNDER WILL ACCOMPANY THE WARM FRONT WITH ACTIVITY REACHING WNY LATER WEDNESDAY NIGHT AND THEN LIFTING ACROSS THE REGION ON THURSDAY. THUNDER WILL BECOME MORE PROBABLE THROUGH THE DAY ON THURSDAY WITH THE ADDITION OF DAYTIME INSTABILITY. FOR NOW THERE LOOKS TO BE SOME CLEARING BEHIND THE WARM FRONT...SUCH THAT SOME SUNSHINE WILL BREAK OUT FROM THE CLOUDS FROM THE STATE LINE TOWARD SOUTHERN LAKE ONTARIO SHORELINE THROUGH THE DAY THURSDAY. IF THIS SUNSHINE IS REALIZED A WARM AFTERNOON IS IN STORE...ALONG WITH A TOUCH OF HUMIDITY. EVENTUALLY THIS WARM FRONT WILL SLOW AND STALL WITH CLOUDS AND CONVECTIVE SHOWERS REMAINING ACROSS THE LAKE ONTARIO AND EASTERN LAKE ONTARIO REGION. THIS WILL LEAVE A CHANCE FOR ACTIVITY THROUGH THE NIGHT ON THURSDAY. A WEAKLY DEFINED COLD FRONT WILL SLOWLY PUSH EASTWARD INTO THE WARM AIRMASS FRIDAY. ALONG THIS FRONT SHOWERS AND PERHAPS A THUNDERSTORM WILL FORM. THERE IS SOME INDICATION THAT A SURFACE WAVE WILL FORM ON THIS FRONTAL BOUNDARY ACROSS THE TENNESSEE VALLEY. IF THIS OCCURS EXPECT THIS COLD FRONT TO BE EVEN SLOWER...WITH THE SURFACE WAVE POSSIBLY BRINGING ANOTHER ROUND OF SHOWERS TO THE REGION ON SATURDAY. TEMPERATURES WILL RISE ABOVE NORMAL...INTO THE 70S THURSDAY AND FRIDAY. THERE IS STILL UNCERTAINTY AS TO WHICH DAY WILL BE THE WARMEST AS CLOUDS MAY BE A LITTLE MORE ABUNDANT ON FRIDAY...WHICH EVEN THOUGH 850S HPA TEMPERATURES MAY BE A DEGREE OR TWO WARMER...THE CLOUDS WILL LIMIT SOLAR HEATING AND LEAVE FRIDAY SLIGHTLY COOLER THAN THURSDAY. ON SATURDAY BEHIND THE COLD FRONT COOLER AIR WILL ADVECT ACROSS THE REGION WITH TEMPERATURES DROPPING BACK INTO THE 60S. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... MID LEVEL TROUGH AXIS LINGERS ACROSS THE LOWER GREAT LAKES REGION THIS LATE THIS EVENING WHICH CONTINUES TO KICK UP SCT SHOWERS ACROSS WESTERN. EAST OF LAKE ONTARIO A MORE ORGANIZED BAND OF SHOWERS WILL SHIFT NORTH ACROSS THE NORTH COUNTY ALONG THE LEADING EDGE OF THE SUPPORTING MID LEVEL TROUGH AXIS. VFR CIGS/VIS WILL PREVAIL OVERNIGHT FOR KBUF/KROC/KIAG WITH JUST TEMPO REDUCTIONS TO MVFR POSSIBLE IN ANY SHRA. FOR KART AND KJHW EXPECT BETTER CHANCES OF MVFR LEVEL CIGS ESPECIALLY ACROSS THE HIGHER TERRAIN. ON SUNDAY A FEW MORE ROUNDS OF SHOWERS ARE LIKELY...ESPECIALLY DURING THE AFTERNOON ACROSS WNY AS ANOTHER MID LEVEL SHORTWAVE CROSSES THE LOWER GREAT LAKES REGION. WESTERLY UPSLOPE FLOW WILL ALLOW FOR CHANCES OF SHOWERS MOST OF THE DAY EAST OF LAKE ONTARIO. A FEW OF THE MORE PERSISTENT SHOWERS MAY PRODUCE SPOTTY/BRIEF MVFR VSBY. CIGS WILL BE MAINLY VFR ACROSS WNY...WITH MVFR MOST LIKELY AT KART EAST OF LAKE ONTARIO. OUTLOOK... MONDAY THROUGH WEDNESDAY...VFR. THURSDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS. && .MARINE... MARGINAL SMALL CRAFT ADVISORY CONDITIONS IN PLACE TONIGHT AS A SLIGHT PRESSURE GRADIENT HAS DEVELOPED ACROSS THE LOWER GREAT LAKES REGION. WEST WINDS WILL INCREASE FURTHER ON SUNDAY AND BRING SOLID SMALL CRAFT ADVISORY CONDITIONS TO LAKE ONTARIO WHICH WILL LAST THROUGH MUCH OF SUNDAY NIGHT. ON LAKE ERIE...SOMEWHAT LESSER WINDS WILL PRODUCE CHOPPY WAVES AT TIMES TONIGHT THROUGH SUNDAY BUT CONDITIONS ARE EXPECTED TO REMAIN JUST BELOW SMALL CRAFT ADVISORY CRITERIA. WINDS AND WAVES WILL DIMINISH ON MONDAY AS A RIDGE OF HIGH PRESSURE BUILDS INTO THE GREAT LAKES REGION. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR LOZ043-044. SMALL CRAFT ADVISORY UNTIL 5 AM EDT MONDAY FOR LOZ042. SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR LOZ045. && $$ SYNOPSIS...HITCHCOCK NEAR TERM...HITCHCOCK/SMITH SHORT TERM...THOMAS LONG TERM...THOMAS AVIATION...HITCHCOCK/SMITH MARINE...HITCHCOCK/SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1026 AM EDT FRI MAY 2 2014 .SYNOPSIS... A PARADE OF UPPER LEVEL DISTURBANCES WILL SWING ACROSS THE GREAT LAKE DURING THE NEXT FEW DAYS...AND THIS WILL CONTINUE TO PRODUCE TIMES OF UNSETTLED WEATHER RIGHT THROUGH THE WEEKEND. A RETURN TO TRUE FAIR WEATHER CAN BE EXPECTED EARLY NEXT WEEK WHEN CANADIAN HIGH PRESSURE WILL BUILD ACROSS OUR REGION. && .NEAR TERM /THROUGH TONIGHT/... RADAR IMAGERY THIS MORNING SHOWING A PERSISTENT AREA OF SHOWERS ACROSS THE HIGHER TERRAIN SOUTH OF BUFFALO AND ROCHESTER...AND ALSO ACROSS THE HIGHER TERRAIN EAST OF LAKE ONTARIO. THIS IS DUE TO COMBINED EFFECTS FROM UPSLOPE FLOW AND DPVA WITH THE PASSAGE OF A WELL DEFINED MID LEVEL SHORTWAVE NOTED IN WATER VAPOR IMAGERY AND OBJECTIVE RUC ANALYSIS. AS THE SHORTWAVE MOVES EAST OF THE AREA THIS AFTERNOON EXPECT COVERAGE OF SHOWERS TO DECREASE ACROSS THE HIGHER TERRAIN...ALTHOUGH IT MAY NOT GO AWAY ALTOGETHER WITH PLENTY OF LOW LEVEL MOISTURE AND DAYTIME HEATING. A FEW SPOTTY SHOWERS MAY ALSO DEVELOP THIS AFTERNOON JUST ABOUT ANYWHERE WITH DAYTIME HEATING AND VERY LIMITED SURFACE BASED INSTABILITY. SOME WEAK LAKE SHADOWS MAY TRY TO FORM NORTHEAST OF LAKES ERIE AND ONTARIO...BUT WITH THE WEALTH OF CLOUD COVER THE LAKE SHADOWS MAY NOT BECOME OVERLY APPARENT. SPEAKING OF CLOUD COVER...RECENT SATELLITE TRENDS AND SHORT TERM MODEL GUIDANCE SUGGEST LITTLE HOPE FOR MUCH IN THE WAY OF SUNSHINE TODAY. THE ONE POSSIBLE EXCEPTION WILL BE ACROSS CENTRAL NY UP TO WATERTOWN...WHERE ENOUGH BREAKS MAY DEVELOP TO ALLOW FOR SOME LIMITED SUNSHINE THIS AFTERNOON. HIGH TEMPS WILL ONLY TOP OUT IN THE LOW TO MID 50S IN MOST AREAS GIVEN THE COOL TEMPS ALOFT AND WEALTH OF CLOUD COVER. TONIGHT WILL THEN FEATURE GENERALLY DRY WEATHER AS THE SHORTWAVE RIDGING WILL GRADUALLY PUSH EAST TO THE ADIRONDACKS AND NEW ENGLAND. MEANWHILE ACROSS THE UPPER GREAT LAKES...THE NEXT ROBUST SHORTWAVE WILL BE TAKING AIM ON OUR REGION. THE LEADING EDGE OF THE PCPN ASSOCIATED WITH THIS FEATURE COULD REACH PARTS OF OUR REGION TOWARDS DAYBREAK. MINS TONIGHT WILL LARGELY BE IN THE LOWER 40S. && .SHORT TERM /SATURDAY THROUGH MONDAY/... IT WILL BE THE SAME OLD STORY THROUGH THE WEEKEND AS MID AND UPPER LEVEL TROUGHING WILL PERSIST ACROSS THE GREAT LAKES AND NORTHEAST... WITH THE RESULTANT LARGE-SCALE CYCLONIC FLOW SENDING ADDITIONAL SHORTWAVE IMPULSES SOUTHEASTWARD ACROSS OUR REGION. THE FIRST SUCH IMPULSE WILL ARRIVE SOMETIME DURING SATURDAY MORNING...WITH A SECOND AND STRONGER FEATURE WORKING INTO THE AREA DURING THE AFTERNOON. COUPLED WITH STEEPENING LAPSE RATES DUE TO DIURNAL WARMING OF OUR COOL AIRMASS...THESE FEATURES SHOULD BRING INCREASING CHANCES OF SHOWERS THROUGH THE DAY...WITH THESE PEAKING DURING THE AFTERNOON HOURS WITH THE APPROACH OF THE SECOND AND STRONGER SHORTWAVE...AND WHEN DIURNALLY-DRIVEN INSTABILITY WILL BE THE GREATEST. AT THIS POINT...IT APPEARS THERE MAY EVEN BE ENOUGH INSTABILITY PRESENT FOR SOME OF THE ACTIVITY TO GET STRONG ENOUGH TO PRODUCE SOME GRAUPEL AND POSSIBLY EVEN A LITTLE LIGHTNING AND THUNDER. WITH ALL OF THIS IN MIND...HAVE INSERTED A SLIGHT CHANCE OF THUNDER INTO THE GRIDS FOR SATURDAY AFTERNOON. LATER ON IN THE WEEKEND...A SIMILAR SCENARIO MAY WELL UNFOLD LATE SATURDAY NIGHT INTO SUNDAY AS AN EVEN STRONGER SHORTWAVE DROPS SOUTHEASTWARD ACROSS NEW YORK STATE...THOUGH THE VARIOUS GUIDANCE PACKAGES CONTINUE TO SHOW SOME SUBTLE DIFFERENCES ON THE EXACT TRACK OF THIS FEATURE...WHICH WILL HAVE AN INFLUENCE ON EXACTLY WHICH AREAS WILL BE MOST LIKELY TO SEE PRECIPITATION. AT THIS POINT...THE NORTH COUNTRY APPEARS TO BE THE AREA MOST PRONE TO ANOTHER ROUND OF SHOWERS...THOUGH MOST LOCATIONS SOUTH OF LAKE ONTARIO SHOULD ALSO SEE A LIKELIHOOD OF A FEW SHOWERS AT SOME POINT DURING THE DAY. AFTER THAT...EXPECT SHOWER CHANCES TO WANE FROM WEST TO EAST SUNDAY NIGHT WITH NOCTURNAL STABILIZATION OF THE LOWER LEVELS AND THE DEPARTURE OF THE SHORTWAVE TO OUR EAST...THOUGH SOME LEFTOVER SCATTERED ACTIVITY MAY WELL LINGER INTO MONDAY MORNING ACROSS THE NORTH COUNTRY THANKS TO LINGERING TROUGHING ALOFT. OTHERWISE... EXPECT MONDAY TO BE A GENERALLY DRY DAY AS SURFACE HIGH PRESSURE RIDGES SOUTHEASTWARD FROM ONTARIO PROVINCE. AS FOR TEMPS...THESE WILL CONTINUE TO AVERAGE A BIT BELOW NORMAL RIGHT THROUGH THE PERIOD GIVEN THE LINGERING TROUGHING ALOFT...AND THE RESULTANT PERSISTENT NORTHWESTERLY FLOW OF SEASONABLY COOL AIR ACROSS OUR REGION. && .LONG TERM /MONDAY NIGHT THROUGH THURSDAY/... THE LATEST MEDIUM RANGE GUIDANCE CONTINUES TO SUGGEST THAT LINGERING UPPER LEVEL TROUGHING OVER EASTERN NORTH AMERICA AT THE START OF THE PERIOD WILL GIVE WAY TO INCREASING RIDGING ALOFT AS A NEW LARGE- SCALE TROUGH DEVELOPS OVER THE WESTERN THIRD OF THE CONTINENT. THIS SHOULD RESULT IN OUR TEMPERATURES EVENTUALLY RETURNING BACK TO NEAR NORMAL LEVELS BY WEDNESDAY...THEN CLIMBING BACK ABOVE NORMAL ON THURSDAY AS A DEVELOPING CYCLONE OVER THE PLAINS STATES HELPS PUMP EVEN WARMER AIR NORTHEASTWARD INTO THE OHIO VALLEY AND NORTHEAST. IN TERMS OF PRECIPITATION CHANCES...PERSISTENT SURFACE-BASED RIDGING DRAPED FROM CENTRAL AND EASTERN CANADA SOUTHEASTWARD INTO THE GREAT LAKES AND NORTHEAST SHOULD KEEP MAINLY DRY CONDITIONS INTACT ACROSS OUR AREA THROUGH WEDNESDAY. AFTER THAT TIME...THE AFOREMENTIONED LOW PRESSURE SYSTEM OVER THE PLAINS WILL PUSH A WARM FRONT IN OUR DIRECTION WEDNESDAY NIGHT AND THURSDAY...WITH INCREASING WARMTH AND MOISTURE ALONG THIS FEATURE BRINGING A RENEWED RISK FOR SOME SHOWERS. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... MVFR CIGS WILL BE FAIRLY WIDESPREAD THROUGH MIDDAY...WITH A FEW HOURS OF IFR CIGS NOT OUT OF THE QUESTION ACROSS THE HIGHER TERRAIN OF THE SRN TIER. NUMEROUS SHOWERS ACROSS THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER LAKES AND ALSO EAST OF LAKE ONTARIO WITH LOCAL MVFR/IFR VSBY WILL BECOME MORE WIDELY SCATTERED THIS AFTERNOON...WITH ADDITIONAL WIDELY SCATTERED SHOWERS POSSIBLE JUST ABOUT ANYWHERE THIS AFTERNOON. CIGS WILL GRADUALLY LIFT DURING THE MIDDAY AND EARLY AFTERNOON...LEAVING VFR CIGS FOR THE BULK OF THE AFTERNOON INTO THE EVENING. LATER TONIGHT...CIGS WILL LIKELY RETURN TO MVFR LEVELS AS THE NEXT FEATURE WILL APPROACH FROM THE UPPER GREAT LAKES. OUTLOOK... SATURDAY AND SUNDAY...VFR/MVFR WITH SCATTERED TO OCCASIONALLY MORE NUMEROUS SHOWERS. MONDAY AND TUESDAY...VFR. && .MARINE... WHILE ONLY A MODESTLY STRONG SFC PRESSURE GRADIENT WILL BE IN PLACE ACROSS THE LOWER GREAT LAKES TODAY...THERE WILL BE ENOUGH DIURNAL MIXING TO TRANSPORT SOME OF THE STRONGER WINDS FROM ALOFT DOWN TO THE LK SFC. THIS WILL ESPECIALLY BE THE CASE OVER LAKE ERIE...WHERE WINDS WILL ONCE AGAIN REACH SMALL CRAFT ADVISORY CRITERIA. WILL ISSUE ANOTHER SCA FOR THE NEW YORK NEARSHORES OF LK ERIE ONLY...AS A FAIR AMOUNT OF ICE REMAINS IN BUF HARBOR. AS FOR LK ONTARIO... MODERATE SOUTHWESTERLIES SHOULD NOT GENERATE SIGNIFICANT WAVES SO NO FLAGS WILL BE NEEDED. WINDS AND WAVES WILL SUBSIDE TONIGHT GIVEN THE DIURNAL UNCOUPLING FROM WINDS ABV 1500 FT. ON SATURDAY...WHILE THE NEXT UPPER LEVEL DISTURBANCE WILL BRING ANOTHER ROUND OF SHOWERS TO THE LOWER GREAT LAKES...A RELATIVELY WEAK SOUTHERLY FLOW IS ANTICIPATED. WINDS WILL FRESHEN SIGNIFICANTLY SATURDAY NIGHT AND SUNDAY THOUGH...WHEN THE NEXT ROUND OF SMALL CRAFT ADVISORIES WILL LIKELY BE NEEDED. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR LEZ040- 041. && $$ SYNOPSIS...RSH NEAR TERM...HITCHCOCK/RSH SHORT TERM...JJR LONG TERM...JJR AVIATION...HITCHCOCK/RSH MARINE...RSH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
300 PM EDT FRI MAY 2 2014 .SYNOPSIS... AN IMPULSE ALOFT APPROACHING FROM THE SOUTHWEST PASS THROUGH THE AREA TONIGHT AND EARLY SATURDAY. SEASONABLE HIGH PRESSURE WILL BUILD IN THROUGH THE WEEKEND. A COLD FRONT WILL PRESS SOUTHWARD AND STALL OVER EASTERN NORTH CAROLINA EARLY NEXT WEEK. WARM HIGH PRESSURE WILL BUILD INTO THE REGION THROUGH THE END OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM FRIDAY...MOSAIC RADAR BEAMS ARE CATCHING WIDESPREAD ECHOS ACROSS THE FORECAST AREA...BUT OBSERVED HOURLY RAINFALL AMOUNTS PAINT A DRIER PICTURE THAN IS PRESENTED GRAPHICALLY BY THE SUITE OF LOCAL 88 DELTAS. OF INTEREST IS SHORT-WAVE ENERGY MOVING FROM THE NE GULF INTO GEORGIA THIS AFTERNOON. THIS FEATURE MAY AID IN STIRRING UPWARD VERTICAL MOTIONS...THROUGH MIDDLE INTO LATE AFTERNOON. THE MOST SIGNIFICANT RAIN AREA OFFSHORE OF N FL AND SC APPEARS ON A TRACK THAT WILL REMAIN OFFSHORE OF OUR COUNTY WARNING AREA. COMPOSITE/CONSENSUS PCPN FIELDS PULL ALL RAIN OFFSHORE BY 11PM EXCEPT FOR THE RAP-13...WHICH IS BIT UNSETTLING SINCE BY THEORY A RAPID UPDATE NEAR-TERM MODEL INGESTS THE LATEST AND GREATEST. THE RAP GENERATES A FEW SHOWERS IN THE PRE-DAWN HOURS ALONG THE COAST...APPARENTLY KEYING ON THE POTENT APPEARING VORT CAREENING INTO WESTERN TN AND WESTERN MS. THIS FEATURE IN FACT DOES IMPART A SURFACE REFLECTION IN THE FORM OF A MINOR AND SECONDARY COLD FRONT. WITH THIS IN MIND WILL KEEP ISOLATED SHOWERS AT THE COAST INTO THE DAYBREAK HOURS. MINIMUMS INTO THE 50S EXPECTED AREA-WIDE BUT COOLEST INLAND...AS A SECONDARY SURGE OF COOL AIR FILTERS INTO THE REGION AFTER 8-9 ZULU/4-5 AM. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...A COLD FRONT JUST OFF THE COAST SAT AM WILL MOVE OUT TO SEA OVER THE WEEKEND AS HIGH PRESSURE RIDGES INTO THE AREA. ANOTHER COLD FRONT WILL APPROACH FROM THE NORTH SUNDAY NIGHT AND MOVE INTO THE AREA LATE. AFTER SOME MORNING CLOUDS AND POSSIBLY A FEW LIGHT SHOWERS EARLY SATURDAY...EXPECT FAIR WEATHER THROUGH THE WEEKEND. MAX TEMPERATURES AWAY FROM THE BEACHES WILL BE IN THE MID TO UPPER 70S SATURDAY AND LOW TO MID 80S SUNDAY. MINS SATURDAY NIGHT WILL BE IN THE LOW TO MID 50S WITH UPPER 50S TO AROUND 60 EXPECTED SUNDAY NIGHT. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 3 PM FRIDAY...OVERALL THE LONG TERM LOOKS PRETTY QUIET. THERE IS SOME UNCERTAINTY AS TO HOW FAR SOUTH A BACKDOOR COLD FRONT PROGRESSES EARLY IN THE PERIOD. MODEL GUIDANCE HAS SHIFTED A BIT TO THE SOUTH AND THE BOUNDARY MAY ENTER NORTHERN ZONES. SOME VERY LOW POPS HAVE BEEN ADDED AS A RESULT. AS THE PARENT HIGH SHIFTS EASTWARD OFF THE MID ATLANTIC COAST THIS BOUNDARY WILL MOVE BACK TO THE NORTH IN A WEAKENING STATE AROUND WEDNESDAY. THE LATTER PART OF THE WEEK WILL BRING RISING HEIGHTS AS UPPER RIDGE BUILDS AND HIGHEST SFC PRESSURES OFF THE COAST. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... AS OF 18Z...CURRENT RADAR IMAGERY SHOWS PATCHES OF LIGHT RAIN MOVING OVER THE EASTERN CAROLINAS ASSOCIATED WITH AN UPPER DISTURBANCE. WILL INCLUDE VCSH FOR ALL TAF SITES THIS AFTERNOON...THOUGH VFR CONDITIONS WILL LIKELY PREVAIL EVEN IN AREAS OF PRECIP. LIGHT NORTHERLY WINDS FROM THIS MORNING WILL BECOME VRB AROUND 5 KTS AFTER 18Z AS A VERY WEAK GRADIENT EXISTS WITH THE FRONT STALLED OFFSHORE. MID LEVEL CIGS WILL PERSIST INTO TONIGHT AS UPPER TROUGH AXIS REMAINS TO OUR WEST. DESPITE THE LIGHT WINDS OVERNIGHT...CLOUD COVER SHOULD INHIBIT FOG DEVELOPMENT. CANNOT RULE OUT TEMPO MVFR CIGS AT KILM/KCRE/KMYR AFTER 06Z...BUT SREF OUTPUT INDICATES THE SUB-VFR CIGS WILL REMAIN OFF THE COAST. EXPECT DECREASING CLOUD COVER BY MIDDAY SATURDAY AS THE UPPER TROUGH FINALLY PUSHES EAST AND USHERS IN SOME DRIER AIR. EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS LATE MONDAY INTO EARLY TUESDAY ASSOCIATED WITH A STALLED FRONT TO OUR NORTH. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM FRIDAY...NO ADVISORIES OR EXERCISE CAUTION HEADLINES WILL BE NEEDED OVERNIGHT. WINDS WILL BE CHANGEABLE BUT NOT STRONG AS A SECONDARY BUT WEAK COLD FRONT PASSES ACROSS THE COAST INTO EARLY SATURDAY JUST PRIOR TO OR AROUND DAYBREAK. SEAS MAINLY 2-3 FEET IN A MIX OF 2-3 FT SSE WAVES EVERY 6-8 SECONDS AND A LIGHT CHOP. LIGHT S-SW WINDS TONIGHT WILL PREVAIL...FOLLOWED BY A WIND- SHIFT TO THE NW INTO FIRST LIGHT OF SATURDAY AS THE FRONT MOVES THROUGH. NO TSTMS EXPECTED OVER THE INSHORE WATERS...BUT A FEW STORMS MAY LIGHT UP THE GULF STREAM INTO EARLY SATURDAY. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 3 PM FRIDAY...LIGHT WEST TO SOUTHWEST FLOW AROUND 10 KT IS EXPECTED SATURDAY AND SATURDAY NIGHT BEFORE BECOMING SOLIDLY SW SUNDAY AND INCREASING TO 15 KT BY AFTERNOON AND CONTINUING INTO SUNDAY NIGHT. WINDS WILL BECOME MORE WESTERLY NORTHERN WATERS LATE AS A FRONT APPROACHES FROM THE NORTH. SEAS OF 2 TO 3 FT EARLY SATURDAY WILL SUBSIDE TO 2 FT OR LESS BY SATURDAY EVENING AND CONTINUE INTO SUNDAY BEFORE BUILDING TO 2 TO 3 FT BY SUNDAY NIGHT. LONG TERM /MONDAY THROUGH WEDNESDAY/... AS OF 3 PM FRIDAY...WITH A BACKDOOR COLD FRONT STALLED CLOSE TO IF NOT ACROSS THE REGION FOR MOST OF THE PERIOD WINDS AND SEAS WILL BOTH BE RATHER MINIMAL. THERE IS SOME UNCERTAINTY REGARDING HOW FAR SOUTH THE BOUNDARY WILL SAG HOWEVER AND THIS TRANSLATES TO SOME POSSIBLE ERROR IN WIND FCST OVER MAINLY NRN ZONES. SRN ZONES SHOULD REMAIN ON THE SOUTH SIDE OF THE BOUNDARY AND THUS KEEP A PREDOMINANTLY SOUTHWESTERN FLOW. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MJC SHORT TERM...31 LONG TERM...MBB AVIATION...BJR/8
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1003 PM CDT SAT MAY 3 2014 .UPDATE... ISSUED AT 1003 PM CDT SAT MAY 3 2014 LATEST MESOSCALE MODELS ARE NOT DOING A GREAT JOB WITH PRECIPITATION OVER NORTHEAST MONTANA THIS EVENING. THE 4 MAY 00 UTC NAM MAY HAVE BEST INITIALIZED THIS SHOWER ACTIVITY. THERE ARE ALSO STILL SOME SHOWERS LOCATED OVER SOUTHEAST MONTANA INTO SOUTHWEST NORTH DAKOTA. LATEST SATELLITE IMAGERY INDICATES SHORTWAVE RIDGE OVER CENTRAL MONTANA BEING FLATTENED WITH SHORTWAVE ENERGY. ALTHOUGH INDIVIDUAL IMPULSES ARE HARD TO DISCERN OVER MONTANA...A STRONGER IMPULSE CAN BE SEEN MOVING ACROSS OREGON. THE AFOREMENTIONED NAM INDICATES A NARROW BAND OF PRECIPITATION TRACKING FROM EASTERN MONTANA THIS EVENING TOWARD THE BISMARCK AREA AROUND 12 UTC SUNDAY. GLOBAL MODELS AND TO A CERTAIN EXTENT...LATEST HRRR/RAP ARE STILL INDICATING THE SOUTHWEST AS THE MORE FAVORED AREA FOR PRECIPITATION OVERNIGHT BEFORE A BETTER CHANCE MOVES INTO THE WEST SUNDAY LATE MORNING OR AFTERNOON. FOR THE EVENING UPDATE...DID GIVE THE NAM SOME CREDIT AND EXTENDED POPS A BIT FARTHER NORTH THAN PREVIOUSLY FORECAST. THIS BROUGHT SOME CHANCE POPS FARTHER NORTH FROM AROUND WATFORD CITY TO THE BISMARCK AREA...BUT STILL LEFT THE HIGHEST POPS ACROSS THE SOUTHWEST FOR NOW. HOPEFULLY WHEN THE 00 UTC GLOBAL MODELS COME IN THERE IS A BETTER CONSENSUS. UPDATE ISSUED AT 649 PM CDT SAT MAY 3 2014 LATEST RADAR IMAGERY CONTINUES TO INDICATED ISOLATED SHOWERS CLIPPING SOUTHWEST NORTH DAKOTA WITH A DIMINISHING STRATOCUMULUS DECK ELSEWHERE. UPDATED POP AND SKY GRIDS BASED ON LATEST RADAR AND SATELLITE IMAGERY AND 22 UTC RAP MESOSCALE OUTPUT. KEPT A SLIGHT CHANCE OF SHOWERS EARLY THIS EVENING OVER THE SOUTHWEST AND DECREASED CLOUDS NORTH WEST AND CENTRAL. BROUGHT SOME HIGHER POPS INTO THE SOUTHWEST LATER THIS EVENING BUT BACKED THIS DOWN A BIT FROM THE PREVIOUS FORECAST BASED ON AFOREMENTIONED RAP GUIDANCE. PRECIPITATION CHANCES THEN INCREASE AFTER MIDNIGHT WITH INCREASING CLOUDS FROM WEST TO EAST. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 THE MAIN CONCERN IN THE SHORT TERM FORECAST PERIOD WILL BE THE CHANCE OF PRECIPITATION TONIGHT AND SUNDAY. THE SHORT TERM MODELS GENERALLY AGREE A FRONTOGENETIC PRECIPITATION BAND WILL DEVELOP LATER TONIGHT ACROSS PARTS OF WESTERN INTO SOUTH CENTRAL NORTH DAKOTA. THERE ARE STILL DIFFERENCES REGARDING HOW MUCH PRECIPITATION WILL ACCUMULATE IN THE BAND...WITH THE GFS MORE AGGRESSIVE THAN MOST SOLUTIONS. WILL USE A BLEND WHICH FAVORS WPC AMOUNTS FOR TONIGHT INTO SUNDAY. THIS WILL BRING NEAR A QUARTER OF AN INCH OF PRECIPITATION ACROSS PARTS OF SOUTHWEST NORTH DAKOTA TONIGHT. FORECAST SOUNDINGS SUGGEST THE RAIN COULD MIX WITH OR CHANGE TO SNOW IN SOME AREAS...AND NAM BUFR SOUNDINGS SHOW AROUND HALF AN INCH OF SNOW POSSIBLE AT KDIK. HAVE INCREASED SNOW AMOUNTS JUST SLIGHTLY IN THE GRIDS IN THE HEART OF THE FRONTOGENETIC BAND...BUT STILL KEPT AMOUNTS LESS THAN AN INCH AND MAINLY EXPECT THOSE ON GRASSY TYPE SURFACES. LATER SHIFTS WILL HAVE TO MONITOR TRENDS SINCE SNOW ACCUMULATIONS WITH FRONTOGENETIC FORCING CAN BE TRICKY. THE INITIAL BAND OF PRECIPITATION SHOULD DIMINISH SUNDAY MORNING...BUT ANOTHER SHORTWAVE APPROACHES THE NORTHERN PLAINS ALREADY SUNDAY AFTERNOON. WILL INCREASE POPS ACROSS THE WEST WITH THE HIGHEST CHANCES NEAR THE MONTANA BORDER. DECIDED TO PULL MENTION OF THUNDER FOR SUNDAY AFTERNOON WITH THE LATEST SHORT TERM MODELS KEEPING THE MUCAPE AXIS WEST AND SOUTH OF NORTH DAKOTA THROUGH SUNDAY AFTERNOON. THE MODELS ALSO DO NOT SHOW ANY CONVECTIVE PRECIPITATION THROUGH 00Z MONDAY...BUT THAT CHANGES SUNDAY NIGHT. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD INCLUDE A CONTINUATION OF ACTIVE WEATHER THROUGH AT LEAST THURSDAY. THE PERIOD BEGINS WITH ZONAL WEST-TO-EAST FLOW ALOFT...THEN TRANSITIONS TO SOUTHWESTERLY FLOW ALOFT AS A LARGE-SCALE LONGWAVE TROUGH DEVELOPS AND DEEPENS OVER THE ROCKIES. THE ROCKIES TROUGH EVENTUALLY BEGINS MOVING OUT INTO THE PLAINS THURSDAY NIGHT...WITH MOST OF THE ENERGY IMPULSES FOR ENHANCED PRECIPITATION TO THE EAST OF THE FORECAST AREA. SUNDAY AFTERNOON AND NIGHT...THE FIRST IN A SERIES OF UPPER LEVEL SHORTWAVE ENERGY IMPULSES MOVES INTO THE STATE. KEPT A SLIGHT CHANCE OF THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. ON MONDAY...A SURFACE WARM FRONT ENTERS WESTERN NORTH DAKOTA AND REACHES THE CENTRAL PART OF THE STATE BY MONDAY EVENING. THIS WILL FOCUS THE LOW LEVEL CONVERGENCE AND PROVIDE GOOD INITIATION OF SHOWERS AND ENOUGH INSTABILITY FOR THUNDERSTORMS ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA. MONDAY NIGHT AND TUESDAY A MORE SIGNIFICANT UPPER LEVEL SHORTWAVE MOVES ACROSS THE STATE. THIS WILL RESULT IN INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS FOR THE FORECAST AREA. AT THIS TIME IT APPEARS THAT THE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT PERIOD SHOULD SEE THE CHANCE OF THUNDERSTORMS RESTRICTED TO SOUTHERN AND SOUTHEASTERN COUNTIES...BUT THE GOOD CHANCES OF SHOWERS REMAIN WITH THE INSTABILITY AND ENERGY IMPULSES IN THE SOUTHWEST FLOW ALOFT. RAINFALL AMOUNTS THROUGH THIS VERY ACTIVE PERIOD SUNDAY NIGHT THROUGH THURSDAY - SUPPORTED BY A CONSENSUS OF MODELS - RANGE FROM 0.5 INCHES TO AROUND 1.5 INCHES. SOME LOCALIZED AREAS MAY RECEIVE 2 INCHES - ESPECIALLY IN THUNDERSTORMS. RENEWED RISES ON AREAS RIVERS ARE LIKELY...BUT THERE IS STILL CONSIDERABLE UNCERTAINTY AS TO WHICH BASINS WILL RECEIVE THE BRUNT OF THE RAIN...AND THE SEVERITY OF THE IMPACTS. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 1003 PM CDT SAT MAY 3 2014 A BAND OF RAIN AND/OR SNOW SHOWERS IS EXPECTED TO MOVE INTO WESTERN NORTH DAKOTA TONIGHT AND SPREAD INTO THE SOUTH CENTRAL SUNDAY MORNING. BASED ON MODEL GUIDANCE KDIK LOOKS TO BE THE AERODROME MOST LIKELY AFFECTED BY MVFR CEILINGS AND VISIBILITIES IN RAIN AND SNOW...WITH KISN AND POSSIBLY RECEIVING A GLANCING BLOW WITH LOWER PROBABILITIES OF MVFR CEILINGS/VISIBILITIES. NORTHWEST FLOW THIS EVENING WILL SHIFT NORTH-NORTHEAST OVERNIGHT AND EVENTUALLY SOUTHEAST AT ALL TAF SITES. WILL MAINTAIN VFR CONDITIONS AT MINOT AND JAMESTOWN THROUGH THE TAF PERIOD. WILL BRING MVFR CEILINGS AND VISIBILITIES INTO DICKINSON AROUND 08 UTC AND CONTINUE THEN CONTINUE MVFR CEILINGS THROUGH THE REST OF THE FORECAST PERIOD. AT KISN WILL BRING A MENTION OF MVFR CEILINGS DURING SUNDAY MORNING. FOR NOW WILL KEEP LOW VFR CEILINGS AT BISMARCK WITH A PERIOD OF RAIN OR SNOW SHOWERS SUNDAY MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...CK LONG TERM...JV AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
659 PM CDT SAT MAY 3 2014 .UPDATE... ISSUED AT 649 PM CDT SAT MAY 3 2014 LATEST RADAR IMAGERY CONTINUES TO INDICATED ISOLATED SHOWERS CLIPPING SOUTHWEST NORTH DAKOTA WITH A DIMINISHING STRATOCUMULUS DECK ELSEWHERE. UPDATED POP AND SKY GRIDS BASED ON LATEST RADAR AND SATELLITE IMAGERY AND 22 UTC RAP MESOSCALE OUTPUT. KEPT A SLIGHT CHANCE OF SHOWERS EARLY THIS EVENING OVER THE SOUTHWEST AND DECREASED CLOUDS NORTH WEST AND CENTRAL. BROUGHT SOME HIGHER POPS INTO THE SOUTHWEST LATER THIS EVENING BUT BACKED THIS DOWN A BIT FROM THE PREVIOUS FORECAST BASED ON AFOREMENTIONED RAP GUIDANCE. PRECIPITATION CHANCES THEN INCREASE AFTER MIDNIGHT WITH INCREASING CLOUDS FROM WEST TO EAST. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 THE MAIN CONCERN IN THE SHORT TERM FORECAST PERIOD WILL BE THE CHANCE OF PRECIPITATION TONIGHT AND SUNDAY. THE SHORT TERM MODELS GENERALLY AGREE A FRONTOGENETIC PRECIPITATION BAND WILL DEVELOP LATER TONIGHT ACROSS PARTS OF WESTERN INTO SOUTH CENTRAL NORTH DAKOTA. THERE ARE STILL DIFFERENCES REGARDING HOW MUCH PRECIPITATION WILL ACCUMULATE IN THE BAND...WITH THE GFS MORE AGGRESSIVE THAN MOST SOLUTIONS. WILL USE A BLEND WHICH FAVORS WPC AMOUNTS FOR TONIGHT INTO SUNDAY. THIS WILL BRING NEAR A QUARTER OF AN INCH OF PRECIPITATION ACROSS PARTS OF SOUTHWEST NORTH DAKOTA TONIGHT. FORECAST SOUNDINGS SUGGEST THE RAIN COULD MIX WITH OR CHANGE TO SNOW IN SOME AREAS...AND NAM BUFR SOUNDINGS SHOW AROUND HALF AN INCH OF SNOW POSSIBLE AT KDIK. HAVE INCREASED SNOW AMOUNTS JUST SLIGHTLY IN THE GRIDS IN THE HEART OF THE FRONTOGENETIC BAND...BUT STILL KEPT AMOUNTS LESS THAN AN INCH AND MAINLY EXPECT THOSE ON GRASSY TYPE SURFACES. LATER SHIFTS WILL HAVE TO MONITOR TRENDS SINCE SNOW ACCUMULATIONS WITH FRONTOGENETIC FORCING CAN BE TRICKY. THE INITIAL BAND OF PRECIPITATION SHOULD DIMINISH SUNDAY MORNING...BUT ANOTHER SHORTWAVE APPROACHES THE NORTHERN PLAINS ALREADY SUNDAY AFTERNOON. WILL INCREASE POPS ACROSS THE WEST WITH THE HIGHEST CHANCES NEAR THE MONTANA BORDER. DECIDED TO PULL MENTION OF THUNDER FOR SUNDAY AFTERNOON WITH THE LATEST SHORT TERM MODELS KEEPING THE MUCAPE AXIS WEST AND SOUTH OF NORTH DAKOTA THROUGH SUNDAY AFTERNOON. THE MODELS ALSO DO NOT SHOW ANY CONVECTIVE PRECIPITATION THROUGH 00Z MONDAY...BUT THAT CHANGES SUNDAY NIGHT. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD INCLUDE A CONTINUATION OF ACTIVE WEATHER THROUGH AT LEAST THURSDAY. THE PERIOD BEGINS WITH ZONAL WEST-TO-EAST FLOW ALOFT...THEN TRANSITIONS TO SOUTHWESTERLY FLOW ALOFT AS A LARGE-SCALE LONGWAVE TROUGH DEVELOPS AND DEEPENS OVER THE ROCKIES. THE ROCKIES TROUGH EVENTUALLY BEGINS MOVING OUT INTO THE PLAINS THURSDAY NIGHT...WITH MOST OF THE ENERGY IMPULSES FOR ENHANCED PRECIPITATION TO THE EAST OF THE FORECAST AREA. SUNDAY AFTERNOON AND NIGHT...THE FIRST IN A SERIES OF UPPER LEVEL SHORTWAVE ENERGY IMPULSES MOVES INTO THE STATE. KEPT A SLIGHT CHANCE OF THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. ON MONDAY...A SURFACE WARM FRONT ENTERS WESTERN NORTH DAKOTA AND REACHES THE CENTRAL PART OF THE STATE BY MONDAY EVENING. THIS WILL FOCUS THE LOW LEVEL CONVERGENCE AND PROVIDE GOOD INITIATION OF SHOWERS AND ENOUGH INSTABILITY FOR THUNDERSTORMS ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA. MONDAY NIGHT AND TUESDAY A MORE SIGNIFICANT UPPER LEVEL SHORTWAVE MOVES ACROSS THE STATE. THIS WILL RESULT IN INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS FOR THE FORECAST AREA. AT THIS TIME IT APPEARS THAT THE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT PERIOD SHOULD SEE THE CHANCE OF THUNDERSTORMS RESTRICTED TO SOUTHERN AND SOUTHEASTERN COUNTIES...BUT THE GOOD CHANCES OF SHOWERS REMAIN WITH THE INSTABILITY AND ENERGY IMPULSES IN THE SOUTHWEST FLOW ALOFT. RAINFALL AMOUNTS THROUGH THIS VERY ACTIVE PERIOD SUNDAY NIGHT THROUGH THURSDAY - SUPPORTED BY A CONSENSUS OF MODELS - RANGE FROM 0.5 INCHES TO AROUND 1.5 INCHES. SOME LOCALIZED AREAS MAY RECEIVE 2 INCHES - ESPECIALLY IN THUNDERSTORMS. RENEWED RISES ON AREAS RIVERS ARE LIKELY...BUT THERE IS STILL CONSIDERABLE UNCERTAINTY AS TO WHICH BASINS WILL RECEIVE THE BRUNT OF THE RAIN...AND THE SEVERITY OF THE IMPACTS. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING) ISSUED AT 659 PM CDT SAT MAY 3 2014 A BAND OF RAIN AND/OR SNOW SHOWERS IS EXPECTED TO MOVE INTO WESTERN NORTH DAKOTA TONIGHT AND SPREAD INTO THE SOUTH CENTRAL SUNDAY MORNING. BASED ON MODEL GUIDANCE KDIK LOOKS TO BE THE AERODROME MOST LIKELY AFFECTED BY MVFR CEILINGS AND VISIBILITIES IN RAIN AND SNOW...WITH KISN AND POSSIBLY RECEIVING A GLANCING BLOW WITH LOWER PROBABILITIES OF MVFR CEILINGS/VISIBILITIES. NORTHWEST FLOW THIS EVENING WILL SHIFT NORTH-NORTHEAST OVERNIGHT AND EVENTUALLY SOUTHEAST AT ALL TAF SITES. WILL MAINTAIN VFR CONDITIONS AT MINOT AND JAMESTOWN THROUGH THE TAF PERIOD. WILL BRING MVFR CEILINGS AND VISIBILITIES INTO DICKINSON AROUND 08 UTC AND CONTINUE THEN CONTINUE MVFR CEILINGS THROUGH THE REST OF THE FORECAST PERIOD. AT KISN WILL BRING A MENTION OF MVFR CEILINGS DURING SUNDAY MORNING. FOR NOW WILL KEEP LOW VFR CEILINGS AT BISMARCK WITH A PERIOD OF RAIN OR SNOW SHOWERS SUNDAY MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...CK LONG TERM...JV AVIATION...TWH
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
403 PM MDT FRI MAY 2 2014 .SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT ISSUED AT 216 PM MDT FRI MAY 2 2014 20Z SURFACE ANALYSIS SHOWED COOL FRONT HAD STALLED FROM CENTRAL MT INTO WESTERN NE INTO NORTHWEST IA. WEAK HIGH PRESSURE BUILDING BEHIND IT. SHORTWAVE ENERGY OVER NORTHEAST MT/ND SUPPORTING BAND OF POST FRONTAL -SHRA FROM EASTERN MT INTO CENTRAL SD...BUT HAVING A BIT OF TROUBLE MAINTAINING THEMSELVES GIVEN DRIER AIR OVER THE CWA. ACTIVITY MAY YET EXPAND PER LOCAL WRF/18Z RAP LATE THIS AFTERNOON/EARLY THIS EVENING AS WEAK MLCAPE DEVELOPS AND SHORTWAVE ENERGY RUSHES PAST. LOWS TONIGHT WILL BE NEAR GUIDANCE. SATURDAY...FRONTAL BOUNDARY WILL MOVE LITTLE AS LOW LEVEL BAROCLINIC ZONE REMAINS STRETCHED FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA. COUPLE OF SHORTWAVES WILL MOVE NORTH OF CWA BRINGING JUST ENOUGH FORCING FOR A FEW -SHRA/DIURNALLY DRIVEN -TSRA GIVEN WEAK MLCAPE. ACTIVITY WILL HAVE BEST CHANCE OVER THE FAR NORTH SATURDAY NIGHT AS LOW LEVEL FLOW BECOMES UPSLOPE AND BEST WAVE MOVES ACROSS ND. TEMPERATURES WILL BE TRICKY GIVEN CLOUD COVER/TIGHT ISOTHERMS...SO TRENDED COOLISH IN THE NORTH AND WARMISH IN THE SOUTH/WEST. && .LONG TERM...SUNDAY THROUGH FRIDAY ISSUED AT 216 PM MDT FRI MAY 2 2014 WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP CHANCES TO THE AREA. FOR THE MID-WEEK...A SPLIT FLOW TROF IS PROGGED TO CROSS THE ROCKIES WITH STRONGER SWRLY FLOW DEVELOPING...BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. DRIER WEATHER MAY RETURN LATER IN THE WORK WEEK...BUT WILL LEAVE SLIGHT CHANCE POPS FOR NOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING) ISSUED AT 401 PM MDT FRI MAY 2 2014 SCT -SHRA WITH ISOLD -TSRA ARE EXPECTED THROUGH THIS EVENING. ISOLD -SHRA WILL BE POSSIBLE LATE TONIGHT THROUGH THE DAY TOMORROW ACROSS PORTIONS OF NE WY TO NW SD AND THE BLKHLS AREA. ISOLD -TSRA ARE POSSIBLE IN THE AFTERNOON. LCL MVFR CONDITIONS WILL BE POSSIBLE IN AND NEAR ANY PRECIP. THERE IS ALSO A CHANCE OF MVFR STRATUS DEVELOPING ACROSS PORTIONS OF NERN WY AND NWRN SD LATE TONIGHT AND SATURDAY MORNING. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...HELGESON LONG TERM...13 AVIATION...JOHNSON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
217 PM MDT FRI MAY 2 2014 .SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT ISSUED AT 216 PM MDT FRI MAY 2 2014 20Z SURFACE ANALYSIS SHOWED COOL FRONT HAD STALLED FROM CENTRAL MT INTO WESTERN NE INTO NORTHWEST IA. WEAK HIGH PRESSURE BUILDING BEHIND IT. SHORTWAVE ENERGY OVER NORTHEAST MT/ND SUPPORTING BAND OF POST FRONTAL -SHRA FROM EASTERN MT INTO CENTRAL SD...BUT HAVING A BIT OF TROUBLE MAINTAINING THEMSELVES GIVEN DRIER AIR OVER THE CWA. ACTIVITY MAY YET EXPAND PER LOCAL WRF/18Z RAP LATE THIS AFTERNOON/EARLY THIS EVENING AS WEAK MLCAPE DEVELOPS AND SHORTWAVE ENERGY RUSHES PAST. LOWS TONIGHT WILL BE NEAR GUIDANCE. SATURDAY...FRONTAL BOUNDARY WILL MOVE LITTLE AS LOW LEVEL BAROCLINIC ZONE REMAINS STRETCHED FROM NORTHWEST TO SOUTHEAST ACROSS THE CWA. COUPLE OF SHORTWAVES WILL MOVE NORTH OF CWA BRINGING JUST ENOUGH FORCING FOR A FEW -SHRA/DIURNALLY DRIVEN -TSRA GIVEN WEAK MLCAPE. ACTIVITY WILL HAVE BEST CHANCE OVER THE FAR NORTH SATURDAY NIGHT AS LOW LEVEL FLOW BECOMES UPSLOPE AND BEST WAVE MOVES ACROSS ND. TEMPERATURES WILL BE TRICKY GIVEN CLOUD COVER/TIGHT ISOTHERMS...SO TRENDED COOLISH IN THE NORTH AND WARMISH IN THE SOUTH/WEST. && .LONG TERM...SUNDAY THROUGH FRIDAY ISSUED AT 216 PM MDT FRI MAY 2 2014 WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP CHANCES TO THE AREA. FOR THE MID-WEEK...A SPLIT FLOW TROF IS PROGGED TO CROSS THE ROCKIES WITH STRONGER SWRLY FLOW DEVELOPING...BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. DRIER WEATHER MAY RETURN LATER IN THE WORK WEEK...BUT WILL LEAVE SLIGHT CHANCE POPS FOR NOW. && .AVIATION...FOR THE 18Z TAFS THROUGH 18Z SATURDAY ISSUED AT 216 PM MDT FRI MAY 2 2014 SCT -SHRA WITH ISOLD -TSRA ARE EXPECTED THROUGH THIS EVENING. ISOLD -SHRA WILL BE POSSIBLE LATE TONIGHT THROUGH THE DAY TOMORROW ACROSS PORTIONS OF NE WY TO NW SD AND THE BLKHLS AREA. ISOLD -TSRA ARE POSSIBLE IN THE AFTERNOON. LCL MVFR VIS/CIGS WILL BE POSSIBLE IN AND NEAR ANY PRECIP. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...HELGESON LONG TERM...13 AVIATION...13
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1128 AM MDT FRI MAY 2 2014 .UPDATE... ISSUED AT 903 AM MDT FRI MAY 2 2014 15Z SURFACE ANALYSIS HAD COOL FRONT FROM KBWP TO KCUT TO KBIL...SLOWLY SINKING SOUTH. SHORTWAVE ENERGY NOTED ON WATER VAPOUR ACROSS SOUTHERN AB/SK...SLINKING SOUTHEAST ON 90KT UPPER LEVEL JET. REGIONAL RADAR LOOP HAD POST FRONTAL SHRA ASSOCIATED WITH SHORTWAVE ENERGY AND STEEP LAPSE RATES PER 12Z KUNR SOUNDING AND SATURATED MID-LEVEL 12Z KGGW SOUNDING. 12Z RAP SHOWED CURRENT ACTIVITY WELL...AND IT SPREADS SHRA ACROSS THE MAJORITY OF THE CWA THROUGH THIS AFTERNOON/EARLY THIS EVENING AND HAVE ADJUSTED SCATTERED POPS TO MATCH. WHERE BETTER DIURNAL HEATING OCCURS...NORTHEAST WY/SOUTHWEST SD...HAVE KEPT TS MENTION GIVEN 250J/KG MUCAPE AVAILABLE DURING PEAK HEATING. HAVE ALSO ADJUSTED TEMPERATURES FOR HIGHER CLOUD COVER. && .SHORT TERM...TODAY THROUGH SATURDAY NIGHT ISSUED AT 303 AM MDT FRI MAY 2 2014 LEAD UPPER LEVEL IMPULSE IN NW FLOW...ADVECTING SE ACROSS THE NORTHERN HIGH PLAINS...WITH AN ASSOCIATED SFC TROUGH NOW ENTERING NW SD /08Z/. THIS SFC TROUGH WILL SAG SOUTH ACROSS THE FA TODAY...WITH IMPULSE LADED NW FLOW SUPPORTING CHANCES FOR SHRA ACROSS THE REGION. LL FRONTAL ZONE WILL WAVER N-S ACROSS THE REGION AS A SERIES OF IMPULSES ADVECT QUICKLY SE THROUGH THE FLOW. DEGREE OF CAA UNDER THE SOUTHERN CANADIAN HEIGHT ANOMALY LOOKS TO BE MUCH STRONGER THAN PREVIOUS MODEL RUNS HAVE INDICATED...SUPPORTING A SOUTH BIAS TO THE SFC COLD FRONT IN THE PERIOD. THIS WOULD TEND TO SUPPORT SLIGHTLY COOLER CONDITIONS ACROSS THE NW HALF...ESP SAT. TODAY/TONIGHT...SFC TROUGH WILL SAG SOUTH INTO THE FA...BEHIND THE LEAD IMPULSE. SECONDARY IMPULSE ON THE HEALS OF HE FIRST WILL SUPPORT A WEAK HIGH CENTERED FGEN RESPONSE WITH SHRA ACTIVITY SPREADING SOUTH INTO NW SD. FORECAST MODELS HAVE BEEN HIGHLY CHANGEABLE PER QPF AMOUNTS ACROSS THE NW...BACKING OFF SIG WITH THE LATEST RUNS TO MORE REASONABLE VALUES GIVEN LIFT PROFILES. COOLER TEMPS EXPECTED THERE GIVEN CLOUDS/PRECIP AND WEAK CAA. FURTHER SOUTH...DIURNAL HEATING WITH THE PASSING WEAK IMPULSE SHOULD BE ENOUGH FOR A FEW ISOLD SHRA/TS BY AFTERNOON. KEPT POPS GENERALLY LOW /SAVE THE FAR NW/ AS THE MAIN LOBE ASCENT WILL REMAIN NORTH OF THE REGION. RETAINED TS CHANCES OVER THE SW WHERE NEGATIVE LI/POS MU CAPE/AND DECENT HEATING IS EXPECTED. ANOTHER WEAK WAVE MAY SUPPORT A FEW SHOWERS OVERNIGHT...WITH LOW POPS RETAINED ACROSS THE NW. SATURDAY...LL BAROCLINIC ZONE WITH ACTIVE NW FLOW WILL PERSIST SUPPORTING LOW CHANCES FOR SHRA IN THE PERIOD. RETAINED LOW POPS...MAINLY NW AREAS FOR EXPECTED PASSING IMPULSES...OF WHICH TIMING/STRENGTH REMAIN MUDDLED. ADJUSTED TEMPS...WITH A STRONG NE/SW TEMP GRADIENT EXPECTED ACROSS THE FA. LOCATIONS NEAR THE GENERAL AREA OF THE FRONT WILL HAVE THE POTENTIAL TO SEE COOLER/WARMER TEMPS...WHICH WILL HINGE ON THE STRENGTH OF PASSING IMPULSES AND THEIR REFLECTED N-S FRONTAL PERTURBATION. && .LONG TERM...SUNDAY THROUGH THURSDAY ISSUED AT 303 AM MDT FRI MAY 2 2014 WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP CHANCES TO THE AREA. TOWARDS MID-WEEK DEEP TROF PUSHES TOWARDS THE ROCKIES WITH STRONGER SWRLY FLOW DEVELOPING BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY) ISSUED AT 1127 AM MDT FRI MAY 2 2014 SCT -SHRA WITH ISOLD AFTERNOON AND EVENING -TSRA ARE EXPECTED THRU THE FORECAST PERIOD. LCL MVFR VIS/CIGS WILL BE POSSIBLE IN PRECIP. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...JC LONG TERM...77 AVIATION...13
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
911 AM MDT FRI MAY 2 2014 .UPDATE... ISSUED AT 903 AM MDT FRI MAY 2 2014 15Z SURFACE ANALYSIS HAD COOL FRONT FROM KBWP TO KCUT TO KBIL...SLOWLY SINKING SOUTH. SHORTWAVE ENERGY NOTED ON WATER VAPOUR ACROSS SOUTHERN AB/SK...SLINKING SOUTHEAST ON 90KT UPPER LEVEL JET. REGIONAL RADAR LOOP HAD POST FRONTAL SHRA ASSOCIATED WITH SHORTWAVE ENERGY AND STEEP LAPSE RATES PER 12Z KUNR SOUNDING AND SATURATED MID-LEVEL 12Z KGGW SOUNDING. 12Z RAP SHOWED CURRENT ACTIVITY WELL...AND IT SPREADS SHRA ACROSS THE MAJORITY OF THE CWA THROUGH THIS AFTERNOON/EARLY THIS EVENING AND HAVE ADJUSTED SCATTERED POPS TO MATCH. WHERE BETTER DIURNAL HEATING OCCURS...NORTHEAST WY/SOUTHWEST SD...HAVE KEPT TS MENTION GIVEN 250J/KG MUCAPE AVAILABLE DURING PEAK HEATING. HAVE ALSO ADJUSTED TEMPERATURES FOR HIGHER CLOUD COVER. && .SHORT TERM...TODAY THROUGH SATURDAY NIGHT ISSUED AT 303 AM MDT FRI MAY 2 2014 LEAD UPPER LEVEL IMPULSE IN NW FLOW...ADVECTING SE ACROSS THE NORTHERN HIGH PLAINS...WITH AN ASSOCIATED SFC TROUGH NOW ENTERING NW SD /08Z/. THIS SFC TROUGH WILL SAG SOUTH ACROSS THE FA TODAY...WITH IMPULSE LADED NW FLOW SUPPORTING CHANCES FOR SHRA ACROSS THE REGION. LL FRONTAL ZONE WILL WAVER N-S ACROSS THE REGION AS A SERIES OF IMPULSES ADVECT QUICKLY SE THROUGH THE FLOW. DEGREE OF CAA UNDER THE SOUTHERN CANADIAN HEIGHT ANOMALY LOOKS TO BE MUCH STRONGER THAN PREVIOUS MODEL RUNS HAVE INDICATED...SUPPORTING A SOUTH BIAS TO THE SFC COLD FRONT IN THE PERIOD. THIS WOULD TEND TO SUPPORT SLIGHTLY COOLER CONDITIONS ACROSS THE NW HALF...ESP SAT. TODAY/TONIGHT...SFC TROUGH WILL SAG SOUTH INTO THE FA...BEHIND THE LEAD IMPULSE. SECONDARY IMPULSE ON THE HEALS OF HE FIRST WILL SUPPORT A WEAK HIGH CENTERED FGEN RESPONSE WITH SHRA ACTIVITY SPREADING SOUTH INTO NW SD. FORECAST MODELS HAVE BEEN HIGHLY CHANGEABLE PER QPF AMOUNTS ACROSS THE NW...BACKING OFF SIG WITH THE LATEST RUNS TO MORE REASONABLE VALUES GIVEN LIFT PROFILES. COOLER TEMPS EXPECTED THERE GIVEN CLOUDS/PRECIP AND WEAK CAA. FURTHER SOUTH...DIURNAL HEATING WITH THE PASSING WEAK IMPULSE SHOULD BE ENOUGH FOR A FEW ISOLD SHRA/TS BY AFTERNOON. KEPT POPS GENERALLY LOW /SAVE THE FAR NW/ AS THE MAIN LOBE ASCENT WILL REMAIN NORTH OF THE REGION. RETAINED TS CHANCES OVER THE SW WHERE NEGATIVE LI/POS MU CAPE/AND DECENT HEATING IS EXPECTED. ANOTHER WEAK WAVE MAY SUPPORT A FEW SHOWERS OVERNIGHT...WITH LOW POPS RETAINED ACROSS THE NW. SATURDAY...LL BAROCLINIC ZONE WITH ACTIVE NW FLOW WILL PERSIST SUPPORTING LOW CHANCES FOR SHRA IN THE PERIOD. RETAINED LOW POPS...MAINLY NW AREAS FOR EXPECTED PASSING IMPULSES...OF WHICH TIMING/STRENGTH REMAIN MUDDLED. ADJUSTED TEMPS...WITH A STRONG NE/SW TEMP GRADIENT EXPECTED ACROSS THE FA. LOCATIONS NEAR THE GENERAL AREA OF THE FRONT WILL HAVE THE POTENTIAL TO SEE COOLER/WARMER TEMPS...WHICH WILL HINGE ON THE STRENGTH OF PASSING IMPULSES AND THEIR REFLECTED N-S FRONTAL PERTURBATION. && .LONG TERM...SUNDAY THROUGH THURSDAY ISSUED AT 303 AM MDT FRI MAY 2 2014 WEST TO SWRLY FLOW OVER THE REGION WILL START THE WEEK WITH A VARIETY OF WEAK DISTURBANCES MOVING THROUGH...BRINGING PRECIP CHANCES TO THE AREA. TOWARDS MID-WEEK DEEP TROF PUSHES TOWARDS THE ROCKIES WITH STRONGER SWRLY FLOW DEVELOPING BRINGING GREATER SHOWER/THUNDERSTORM CHANCES. && .AVIATION...FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING ISSUED AT 303 AM MDT FRI MAY 2 2014 SCT -SHRA WITH ISOLD AFTERNOON AND EVENING -TSRA ARE EXPECTED THRU THE FORECAST PERIOD. LCL MVFR VIS WILL BE POSSIBLE IN PRECIP. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...HELGESON SHORT TERM...JC LONG TERM...77 AVIATION...77
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
235 PM CDT FRI MAY 2 2014 .SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT) ISSUED AT 235 PM CDT FRI MAY 2 2014 MAIN FORECAST CONCERNS THIS PERIOD...CLOUDS/TEMPERATURES...SMALL -SHRA CHANCES NORTHEAST OF I-94 SAT AND MAINLY NORTHEAST IA LATE SAT NIGHT. DATA ANALYSIS AT 18Z HAD A RATHER VIGOROUS MID LEVEL SHORTWAVE DROPPING SOUTHEAST ACROSS MN. STRONGEST 3HR PRESSURE FALLS OF 2-3MB WERE OVER CENTRAL MN WITH A SFC LOW/TROUGH AND COLD FRONT ALSO DROPPING SOUTHEAST ACROSS MN. FORCING/LIFT AHEAD OF THESE FEATURES RESPONSIBLE FOR A BAND OF -RA/-SHRA MOVING ACROSS WESTERN WI AND NORTHEAST IA WITH SPOTTY -SHRA ACROSS EAST-CENTRAL/SOUTHEAST MN BEHIND THE LEADING LINE. ANY RAIN AMOUNTS HAVE BEEN QUITE LIGHT. SOME DECREASE OF CLOUDS BEHIND THE LEADING -RA/-SHRA LINE...WITH MID-DAY TEMPS WARMING INTO THE 50S ACROSS CENTRAL IA TO CENTRAL MN. 02.12Z MODEL INITIALIZED QUITE WELL AND OFFER SIMILAR SOLUTIONS FOR TONIGHT THRU SAT NIGHT AS HGTS ALOFT SLOWLY RISE BUT NORTHWEST FLOW ALOFT PERSISTS OVER THE UPPER MIDWEST. TREND FAVORS STRONGER OF THE EARLIER SOLUTIONS WITH THE SHORTWAVE QUICKLY PASSING THIS AFTERNOON. TREND FOR SAT/SAT NIGHT FAVORS A COMPROMISE OF THE EARLIER RUNS AS RIDGING ALOFT BUILDS INTO THE NORTHERN PLAINS AND HGTS OVER THE REGION GRADUALLY START TO RISE. NO ONE DETERMINISTIC MODEL FAVORITE AND WITH THE TIGHT CONSENSUS...FAVORED THE MODEL/ ENSEMBLE COMPROMISE THIS CYCLE. SHORT TERM FCST CONFIDENCE IS GOOD THIS CYCLE. IN THE SHORT TERM...GENERALLY DRIER WEATHER IN STORE FOR THE FCST AREA TONIGHT THRU SAT NIGHT. SHORTWAVE WILL EXIT QUICKLY LATE THIS AFTERNOON/EARLY THIS EVENING WITH DEEP LAYERED SUBSIDENCE/ DRYING SPREADING ACROSS THE AREA. ANY SCT SHRA/ISOLATED TSRA FROM THIS AFTERNOON WILL DIMINISH/EXIT QUICKLY THIS EVENING WITH LOSS OF THE MOISTURE AND DIURNAL HEATING. WILL FINE TUNE -SHRA CHANCES FOR LATER THIS AFTERNOON/EARLY THIS EVENING BASED ON CURRENT CONDITIONS AT MID AFTERNOON. IN THE WAKE OF THE SFC-MID LEVEL TROUGH AND UNDER THE RISING HGTS ALOFT...WEAK CAN HIGH PRESSURE BUILDS INTO THE UPPER MIDWEST FOR LATER TONIGHT INTO SAT NIGHT. LATER THIS EVENING THRU SAT EVENING TRENDING DRY WITH THIS HIGH PRESSURE OVER ALL BUT THE NORTHEAST END OF THE FCST AREA SAT AFTERNOON. THIS DUE TO PROXIMITY OF A SHORTWAVE DROPPING SOUTHEAST ACROSS LK SUPERIOR...STEEPER SFC- 700MB LAPSE RATES/WEAK INSTABILITY AND A BIT MORE LINGERING 850-700MB MOISTURE. SMALL -SHRA CHANCE NORTHEAST OF I-94 SAT AFTERNOON REASONABLE FOR NOW. HIGH CONTINUES TO NOSE IN SAT NIGHT BUT SIGNAL REMAINS FOR A MDT/STRONG SURGE OF 700-500MB WARM ADVECTION/ ISENTROPIC LIFT/ MOISTURE TRANSPORT WITH PW/S TO AROUND 0.75 INCH TO OVER- RUN THE SOUTHWEST SIDE OF THE HIGH/COOL DOME LATE SAT NIGHT. THIS WITH SOME 700-500MB FN CONVERGENCE AND DIVERGENCE ALOFT IN THE RIGHT ENTRANCE REGION OF A 130KT 300MB JET MAX ACROSS WI. GIVEN THE PERSISTENCE/CONSENSUS FOR THIS MOISTURE/LIFT SIGNAL...CONTINUED THE SMALL -RA/-SHRA CHANCE ACROSS THE SOUTHWEST END OF THE FCST AREA LATE SAT NIGHT. COOLER NIGHT TONIGHT WITH A DECREASE OF CLOUDS FOR MUCH OF THE AREA AND A COOLER LOW LEVEL AIRMASS SETTLING INTO THE REGION WITH THE WEAK CAN HIGH PRESSURE. EVEN COOLER AIRMASS TO SETTLE IN FOR SAT NIGHT...WITH LOWS FOR SAT NIGHT LOOKING TO BE MOSTLY IN THE 30S. SOME FROST POSSIBLE ALONG/NORTHEAST OF I-94 SAT NIGHT BUT GIVEN THE LATENESS OF THE SPRING SEASON...IT IS A BIT EARLY TO BE ISSUING FROST ADVISORIES AT THIS POINT. PLAN IS TO START THOSE FOR MOST OF THE FCST AREA NEXT WEEK. WITH PARTLY TO MOSTLY SUNNY SKIES SAT... CONSENSUS HIGHS MOSTLY IN THE MID 50S TO LOW 60S LOOK GOOD. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 235 PM CDT FRI MAY 2 2014 MAIN FORECAST CONCERNS FOR SUNDAY THROUGH MONDAY NIGHT...-RA/-SHRA CHANCES SUN MORNING AND AGAIN MON...TEMPERATURES THRU THE PERIOD. MODELS IN DECENT AND IMPROVING AGREEMENT WITH SLOWLY RISING HGTS OVER THE NORTH-CENTRAL CONUS IN THE SUN THRU MON NIGHT PERIOD. LITTLE TREND FROM THE PREVIOUS RUNS IN THIS PERIOD AS FAR AS TIMING OF FEATURES...THUS FCST CONFIDENCE IN THE SUN THRU MON NIGHT PERIOD IS GENERALLY GOOD THIS CYCLE. FORCING/LIFT/MOISTURE SIGNAL FROM LATE SAT NIGHT TRANSLATES QUICKLY EAST/SOUTHEAST ACROSS THE SOUTHWEST 1/3 TO 1/2 OF THE FCST AREA SUN MORNING. RATHER CONSISTENT SIGNAL AMONG THE MODELS FOR THIS MAINLY 700-500MB LIFT/MOISTURE TO PRODUCE SOME LIGHT PRECIP ACROSS THE SOUTHWEST 1/2 OF THE FCST AREA WITH THE CONSENSUS 20-50 PERCENT -RA/ -SHRA CHANCES REASONABLE FOR NOW. TRENDED -RA CHANCES QUICKLY DOWN AND OUT FOR THE AFTERNOON WITH THE FAST EXIT OF THE FORCING. DRY SUN EVENING BUT ANOTHER ROUND OF MID LEVEL THERMO-DYNAMIC FORCING/LIFT ASSOCIATED WITH A SHORTWAVE SLIDING THRU THE MID LEVEL RIDGE ALREADY SPREADS INTO THE FCST AREA LATER SUN NIGHT. PW VALUES WITH THIS ROUND OF FORCING/LIFT...INCLUDING SOME 300MB JET MAX RIGHT ENTRANCE REGION DIVERGENCE...AGAIN IN THE 0.50 TO 0.75 INCH RANGE. GIVEN THE PERSISTENCE/AGREEMENT ON THE FORCING/LIFT SIGNAL...CONTINUED THE SMALL -RA CHANCE FOR MUCH OF THE FCST AREA LATER SUN NIGHT AND MON. DRY/QUIET MON NIGHT WITH MID LEVEL RIDGE AXIS BUILD OVER THE UPPER MIDWEST...NO 850-500MB FORCING/LIFT SEEN AND WEAK HIGH PRESSURE AT THE SFC. 850MB TEMPS OVER THE AREA PROGGED TO REMAIN 0.5 TO 1 STANDARD DEVIATION BELOW NORMAL THRU THIS PERIOD. WITH PERIODIC CLOUDS...SUN/MON HIGHS TO REMAIN ON THE SEASONABLY COOL SIDE. WITH A COOLER/MOSTLY CLOUDY DAY SUNDAY THEN LIGHT WINDS AND PARTLY CLOUDY SKIES MUCH OF SUN NIGHT...MOST MON MORNING LOWS LOOKING TO BE IN THE 30S. GENERALLY STAYED WITH THE MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR SUN THRU MON NIGHT. FOR TUESDAY THROUGH FRIDAY.../DAYS 4 TO 7/... MAIN CONCERNS ARE TEMPERATURES AND SHRA/TSRA CHANCES THRU THE PERIOD. MEDIUM RANGE MODEL RUNS OF 02.00Z AND 02.12Z IN GOOD AND IMPROVING AGREEMENT ON TUE...FOR STRONG TROUGHING TO DIG INTO THE ROCKIES AND RIDGING ALOFT TO BUILD ACROSS THE MID/UPPER MS VALLEY. ECMWF/GFS WITH SURPRISINGLY GOOD RUN-TO-RUN CONSISTENCY WITH THEIR 30.12Z AND 01.12Z RUNS ON TUE. 02.00Z ECMWF APPEARED AS AN OUTLIER WED/THU BUT ITS 02.12Z RUN IS MORE IN LINE WITH THE GFS/CAN-GEM AND PREVIOUS RUN CONSENSUS. SURPRISINGLY GOOD ECMWF/GFS AGREEMENT ON FRI WITH BROAD LONG-WAVE TROUGHING OVER CENTRAL NOAM. DAY 4-7 FCST CONFIDENCE IS GOOD TUE...THEN WITH SOME MODEL DETAIL DIFFERENCES HAVING IMPACTS ON THE SENSIBLE WEATHER FOR WED AND BEYOND...FCST CONFIDENCE FOR DAYS 5 THRU 7 IS AVERAGE. TUE CONTINUES TO TREND TOWARD A DRY DAY WITH THE MID LEVEL RIDGE AXIS MOVING ACROSS THE REGION....SFC HIGH PRESSURE OVER THE GREAT LAKES AND THE MAIN AXIS OF 850MB WARM ADVECTION/MOISTURE TRANSPORT WEST OF THE FCST AREA. WARMING 850MB TEMPS ON TUE SUPPORT HIGHS IN THE 60S. MID LEVEL RIDGE AXIS IS QUICKLY PUSHED EAST TUE NIGHT... WITH THE AREA UNDER SOUTHWEST FLOW ALOFT FOR WED-THU AS PIECES OF ENERGY EJECT OUT OF THE WESTERN CONUS TROUGH. THIS EJECTING ENERGY SENDS A RATHER STRONG COLORADO LEE LOW NORTHEAST ACROSS THE CENTRAL PLAINS TOWARD THE UPPER MIDWEST. DIFFERENCES WHERE THE SFC LOW AND ITS ASSOCIATED FRONTS AND WARM SECTOR END UP BY WED NIGHT/ THU. THIS HAS IMPACTS ON THE SENSIBLE WEATHER WED-THU AS FAR AS TEMPS AND SHRA/TSRA CHANCES...DEPENDING ON WHERE THIS LOW TRACKS AND THE FRONTS END UP. GIVEN THE AVERAGE CONFIDENCE BY WED/THU... FOLLOWED THE MODEL/ENSEMBLE CONSENSUS WHICH WOULD TRACK THE LOW INTO SOUTHERN MN BY EARLY THU. SHRA/TSRA CHANCES MOSTLY IN THE 30-50 PERCENT RANGE FOR TUE NIGHT THRU THU APPEAR REASONABLE AT THIS TIME. LOWER/DECREASING SHRA/TSRA CHANCES THU NIGHT/FRI ALSO APPEAR REASONABLE WITH THE MAIN SFC LOW/MID LEVEL TROUGH MOVING EAST OF THE AREA. HOWEVER THERE ARE DETAIL DIFFERENCES WITH SHORTWAVES IN THE WHAT WOULD BE BROAD TROUGHING OVER THE REGION LATE IN THE WEEK. MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS CLOSER TO NORMAL FOR TUE-FRI LOOK WELL TRENDED FOR NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1202 PM CDT FRI MAY 2 2014 WATER VAPOR SATELLITE LATE THIS MORNING SHOWS A SHORT WAVE TROUGH OVER CENTRAL MINNESOTA MOVING QUICKLY SOUTHEAST. AT THE SURFACE... LOW PRESSURE WAS ALSO OVER CENTRAL MINNESOTA BETWEEN KSAZ AND KJMR WITH A FRONT/WIND SHIFT LINE SOUTH INTO NORTHWEST IOWA. A FEW SHOWERS OUT AHEAD OF THE SURFACE LOW AND FRONT WITH VFR CEILINGS AND NO VISIBILITY RESTRICTION. EXPECT THAT THESE WILL PASS THROUGH EARLY THIS AFTERNOON AND THE QUESTION BECOMES IF MORE WILL DEVELOP WITH THE PASSAGE OF THE SURFACE LOW AND FRONT. BOTH THE 02.00Z HI- RES ARW AND 02.12Z NAM SUGGEST ADDITIONAL SCATTERED ACTIVITY COULD DEVELOP SO WILL HOLD ONTO THE VCSH THROUGH THE AFTERNOON. THE 02.15Z RAP KEEPS THE INSTABILITY PRETTY LIMITED WITH MAYBE 150 J/KG OF MU CAPE SO WILL CONTINUE TO NOT INCLUDE ANY THUNDER CHANCES UNLESS SOMETHING POPS UP. ONCE THE FRONT GOES THROUGH... LOOK FOR THE WINDS TO COME AROUND TO THE NORTHWEST AND THE VFR CEILINGS TO SCATTER OUT. VFR CONDITIONS THEN EXPECTED FOR THE REMAINDER OF THE PERIOD WITH SOME GUSTY NORTHWEST WINDS FOR KRST BY MID MORNING SATURDAY. && .HYDROLOGY... ISSUED AT 235 PM CDT FRI MAY 2 2014 RUNOFF FROM RECENT RAIN CONTINUES TO FLOW THROUGH THE MISSISSIPPI RIVER TRIBUTARIES AND THE MAIN CHANNEL. CURRENTLY ONLY THE MISSISSIPPI RIVER AT WABASHA IS IN FLOOD...BUT FORECASTS CONTINUE TO POINT TO THE MISSISSIPPI RIVER AT WINONA...LA CROSSE...MCGREGOR AND GUTTENBERG DAM 10 TO BEGIN MINOR FLOODING IN THE NEXT 1 TO 4 DAYS. IN ADDITION...THE BLACK RIVER NEAR GALESVILLE WI IS NEAR ITS CREST JUST ABOVE FLOOD STAGE AND WILL FALL BACK BELOW FLOOD STAGE ON SAT. NO MAJOR RAINS ARE ANTICIPATED OVER THE NEXT 5 DAYS SO RUNOFF ALREADY IN THE RIVER CHANNELS WILL BE THE MAIN CONTRIBUTING FACTOR TO RIVER LEVELS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RRS LONG TERM....RRS AVIATION.....04 HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1202 PM CDT FRI MAY 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 240 AM CDT FRI MAY 2 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO BRITISH COLUMBIA...AN UPPER LOW AND SHORTWAVE TROUGH OVER NORTHERN ALBERTA/SASKATCHEWAN... A SHORTWAVE TROUGH OVER SOUTHERN MANITOBA...AND AN ELONGATED LONG WAVE TROUGH FROM TEXAS INTO THE GREAT LAKES. THE FORECAST AREA LIES NOW IN SUBSIDENCE IN THE WAKE OF THE LONG WAVE TROUGH...PROMOTING DRY AIR ADVECTION FROM THE NORTHWEST. THIS CAN BE SEEN BY THE LOW STRATUS DECK CLEARING ACROSS MINNESOTA ON 11-3.9UM IMAGERY AND SURFACE OBSERVATIONS. 00Z BIS AND ABR SOUNDINGS WERE ALSO QUITE DRY WITH PRECIPITABLE WATER OF ONLY 0.3-0.4 INCHES. REPLACING THE STRATUS DECK HAS BEEN MID AND HIGH CLOUDS SPREADING SOUTHEAST ACROSS THE DAKOTAS AND MINNESOTA...AHEAD OF THE SHORTWAVE THERE. GRAND FORKS RADAR DISPLAYING SOME LIGHT RETURNS AS WELL...BUT SO FAR THE DRY AIR HAS BEEN WINNING OUT KEEPING THE PRECIPITATION AS VIRGA. AIRMASS OVER THE FORECAST AT 00Z WAS STILL UNSEASONABLY COOL WITH 925MB TEMPS AROUND 4C...BUT WARMER 9-13C READINGS WERE LURKING UPSTREAM AT ABR AND BIS. BEHIND THE SHORTWAVE TROUGH IN SOUTHERN MANITOBA...SKIES CLEAR OUT AND SURFACE PRESSURES WERE RISING ABOUT 1 MB/HR...PROMOTING GUSTY WINDS ACROSS NORTH DAKOTA. MODELS ARE IN GOOD AGREEMENT DROPPING THE SOUTHERN MANITOBA SHORTWAVE SOUTHEASTWARD THROUGH THE FORECAST AREA THIS AFTERNOON. MORE IMPORTANTLY...THERE IS A CONSISTENT SIGNAL FROM ALL MODELS FOR THE SHORTWAVE TO WEAKEN SOME. THIS WEAKENING COMBINED WITH THE DRY ADVECTION CURRENTLY TAKING PLACE FROM THE NORTHWEST BRINGS IN SOME CONCERN FOR PRECIPITATION CHANCES TODAY. HARD TO FIND A MODEL THAT DOESNT PRECIPITATE WITH THE SHORTWAVE...WHICH MAKES SENSE IN GENERAL GIVEN WE HAVE A SHORTWAVE TROUGH COMING THROUGH AT PEAK HEATING. BETWEEN DYNAMICS AND INSTABILITY FROM HEATING...SHOWERS DEVELOPING IS REASONABLE. HOWEVER...IT IS WORTH NOTING THAT 2 METER DEWPOINT GUIDANCE FROM THE BASE MODELS SUCH AS THE ECMWF...GFS...NAM AND REGIONAL CANADIAN ALL PUSH DEWPOINTS WELL INTO THE 40S...WITH EVEN THE GFS AND REGIONAL CANADIAN APPROACHING 50 BY 00Z. THIS SEEMS A BIT HIGH GIVEN CURRENT SURFACE DEWPOINTS IN THE UPPER 20S TO MID 30S OVER THE DAKOTAS. PERHAPS THE MODELS ARE THINKING GREEN-UP HAS ALREADY TAKEN PLACE BASED ON CLIMATOLOGY. WE DO HAVE WET SOILS SO THAT COULD PROMOTE SLIGHTLY HIGHER DEWPOINTS. IN SUMMARY...FEEL FAIRLY CONFIDENT THAT WE WILL SEE SHOWERS THIS AFTERNOON...BUT A LITTLE LESS CERTAIN ON IF THEY WILL BE WIDESPREAD. ANOTHER CHANGE WORTH NOTING IS THAT THE 02.00Z NAM MUCAPE THIS AFTERNOON HAS DROPPED FROM PREVIOUS RUNS...NOW BELOW 200 J/KG...WHICH MAKES SENSE. CONSIDERED DROPPING THE THUNDER MENTION ENTIRELY AS A RESULT...BUT THE RAP DOES DEPICT A ZONE OF 700-500MB LAPSE RATES APPROACHING 7 C/KM OVER THE FORECAST AREA DURING THE AFTERNOON. THEREFORE...HAVE LEFT THE THUNDER IN THE FORECAST FOR THE AFTERNOON. ANY SHOWER ACTIVITY SHOULD QUICKLY EXIT THE AREA BETWEEN 00-03Z WITH THE SHORTWAVE EXITING AND DIURNAL COOLING. AS WE APPROACH LATE TONIGHT...MORE SHOWER ACTIVITY LOOKS TO DROP DOWN INTO NORTHERN MN AND WI. THESE ARE AHEAD OF THE SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN... PROGGED TO BE OVER SOUTHERN MANITOBA AND NORTHERN MN BY 12Z SATURDAY. ITS POSSIBLE THIS SHOWER ACTIVITY COULD GET INTO TAYLOR COUNTY TOWARDS 12Z...BUT FOR NOW HAVE KEPT THE FORECAST DRY. 925MB TEMPERATURES ARE PROGGED A FEW DEGREES WARMER TODAY...BETWEEN 6-8C FOR THE AFTERNOON HOURS. THERE IS A CHANCE WE CAN SNEAK IN A LITTLE SUN AND WITH A WARM ADVECTING SOUTHWEST WIND...MOST LOCATIONS WILL CLIMB INTO THE 50S. THERES EVEN A CHANCE SOME SPOTS COULD PUSH 60...SUCH AS CHARLES CITY...WINONA...LA CROSSE AND BOSCOBEL. THIS ALL HINGES IF WE CAN GET MORE SUN...BUT THINK OVERALL WE WILL BE CLOUDY OR MOSTLY CLOUDY TODAY. COLD ADVECTION TONIGHT ON A NORTHWEST WIND...WHICH COULD BE BRISK IN THE EVENING WEST OF THE MS RIVER WITH THE PRESSURE RISE COMING THROUGH...WILL ALLOW TEMPERATURES TO DROP INTO THE 30S TO LOW 40S TONIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 240 AM CDT FRI MAY 2 2014 UPPER LEVEL PATTERN CHANGE REMAINS ON TRACK DURING THE LONG TERM PERIOD...WITH UPPER RIDGING CURRENTLY OVER THE WESTERN U.S. PROGGED TO BUILD OVER THE REGION LATE TUESDAY INTO WEDNESDAY. THIS IS ALL IN RESPONSE TO AN UPPER LOW CURRENTLY OFF THE PACIFIC NORTHWEST COAST SUGGESTED TO DIG INTO THE SOUTHWESTERN U.S.. THIS PATTERN CHANGE MEANS A GRADUAL MODERATION OF TEMPERATURES...ALONG WITH POTENTIAL FOR MORE ACTIVE WEATHER AS WE APPROACH THE MIDDLE OF NEXT WEEK. FIRST OFF...SATURDAY. THAT NEXT SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN WILL SLIDE ACROSS NORTHERN PORTIONS OF MN AND WI...ALONG WITH UPPER MI AND ONTARIO DURING THE DAY AND EVENING HOURS. THIS TRACK KEEPS THE BEST DPVA FORCING NORTH OF THE FORECAST AREA. THEREFORE...THINK MUCH OF THE PRECIPITATION WILL STAY NORTH AS WELL. HOWEVER...THERE WILL BE A SURFACE COLD FRONT ACCOMPANYING THE SHORTWAVE. THE 02.00Z GFS PRINTS OUT SOME LIGHT QPF OVER LA CROSSE AS THE FRONT COMES THROUGH... MOSTLY A RESULT OF THE MODEL DEVELOPING SOME WEAK CAPE. BELIEVE THE MODEL IS TOO FAR SOUTH AND OVERLY MOIST. HAVE DECIDED TO KEEP ANY LOW CHANCES OF PRECIPITATION NORTH OF I-94...CONSISTENT TOO WITH THE 02.00Z ECMWF. 925MB TEMPS REBOUND DECENTLY ON SATURDAY...6-9C... ALLOWING TEMPERATURES TO CLIMB SLIGHTLY HIGHER THAN THOSE TODAY. NEXT UP IS ON SUNDAY WHERE THE 02.00Z GFS/CANADIAN/ECMWF/NAM ALL DEVELOP A FRONTOGENETICAL BAND OF PRECIPITATION. THE BAND ALSO HAS SOME RIGHT ENTRANCE REGION FORCING FROM A JET STREAK FOLLOWING THE SATURDAY SHORTWAVE TROUGH. THE NAM IS THE ODD MODEL OUT ON LOCATION OF THE BAND...TRACKING IT FROM MINNEAPOLIS TO LA CROSSE AND THE DELLS...WHEREAS ALL OTHER MODELS SUGGEST SOUTHWEST MN INTO NORTHERN IA AND NORTHERN IL AS THE MORE LIKELY TRACK. GIVEN GOOD AGREEMENT ON THIS FRONTOGENETIC BAND FROM THE OTHER MODELS...HAVE RAISED PRECIPITATION CHANCES. MODEL CONSENSUS SUGGESTS 12-18Z SUNDAY IS THE MOST LIKELY TIME PERIOD FOR PRECIPITATION WITH THE PRECIPITATION EXITING RAPIDLY TO THE SOUTHEAST IN THE AFTERNOON. THERE IS SOME LOWER LEVEL DRY AIR PRESENT...WHICH IF THE PRECIPITATION WAS HEAVIER MIGHT CAUSE PRECIPITATION TYPE ISSUES FROM EVAPORATIVE COOLING. FOR NOW WILL KEEP THE PRECIPITATION TYPE AS RAIN GIVEN GENERALLY LIGHT QPF PROGGED BUT SOMETHING TO WATCH. WITH THIS FRONTOGENETICAL BAND GOING THROUGH AND A NORTHEAST BREEZE...TEMPERATURES ARE GOING TO TAKE A COOL DOWN. THIS IS ESPECIALLY TRUE UNDER THE PRECIPITATION. RAIN CHANCES COME BACK FOR MONDAY WHEN YET ANOTHER BAND OF FRONTOGENESIS AND ISENTROPIC LIFT MOVES ACROSS. THIS ONE LOOKS WEAKER THAN ON SUNDAY...THUS 02.00Z GFS/CANADIAN/ECMWF QPF IS LIGHTER AND MORE SPREAD OUT ACROSS THE FORECAST AREA. CONSENSUS 20 PERCENT CHANCES SEEM REASONABLE. COOLED HIGHS SLIGHTLY FROM THE PREVIOUS FORECAST DUE TO CLOUDS AND AN EAST WIND AROUND HIGH PRESSURE IN UPPER MI. THESE COULD NEED FURTHER COOLING IF A LITTLE MORE PRECIPITATION IS AROUND AS SUGGESTED BY THE 02.00Z ECMWF. AS THE UPPER RIDGE BUILDS INTO THE AREA LATE TUESDAY AND ESPECIALLY WEDNESDAY...THAT IS WHEN SOME BIGGER TEMPERATURE CHANGES TAKE PLACE...ALONG WITH INCREASING CONCERNS FOR CONVECTION AND POSSIBLE SEVERE WEATHER. 02.00Z GFS/ECMWF SUGGEST THAT BETWEEN 12Z WEDNESDAY AND 00Z THURSDAY...925MB TEMPS COULD CLIMB AS MUCH AS 10-15C RESULTING IN AN ALMOST SUMMER-LIKE AIRMASS COMING INTO LOCATIONS ALONG AND SOUTH OF I-90. WE WILL HAVE TO WAIT AND SEE HOW THIS PANS OUT. IN ANY EVENT...HAVE FOLLOWED CONSENSUS WITH 30-50 PERCENT CHANCES FOR TUESDAY NIGHT AND WEDNESDAY...WITH SLIGHTLY HIGHER CHANCES FOR WEDNESDAY NIGHT INTO THURSDAY RESULTING FROM A SHORTWAVE TROUGH COMING THROUGH THE UPPER MIDWEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1202 PM CDT FRI MAY 2 2014 WATER VAPOR SATELLITE LATE THIS MORNING SHOWS A SHORT WAVE TROUGH OVER CENTRAL MINNESOTA MOVING QUICKLY SOUTHEAST. AT THE SURFACE...LOW PRESSURE WAS ALSO OVER CENTRAL MINNESOTA BETWEEN KSAZ AND KJMR WITH A FRONT/WIND SHIFT LINE SOUTH INTO NORTHWEST IOWA. A FEW SHOWERS OUT AHEAD OF THE SURFACE LOW AND FRONT WITH VFR CEILINGS AND NO VISIBILITY RESTRICTION. EXPECT THAT THESE WILL PASS THROUGH EARLY THIS AFTERNOON AND THE QUESTION BECOMES IF MORE WILL DEVELOP WITH THE PASSAGE OF THE SURFACE LOW AND FRONT. BOTH THE 02.00Z HI-RES ARW AND 02.12Z NAM SUGGEST ADDITIONAL SCATTERED ACTIVITY COULD DEVELOP SO WILL HOLD ONTO THE VCSH THROUGH THE AFTERNOON. THE 02.15Z RAP KEEPS THE INSTABILITY PRETTY LIMITED WITH MAYBE 150 J/KG OF MU CAPE SO WILL CONTINUE TO NOT INCLUDE ANY THUNDER CHANCES UNLESS SOMETHING POPS UP. ONCE THE FRONT GOES THROUGH...LOOK FOR THE WINDS TO COME AROUND TO THE NORTHWEST AND THE VFR CEILINGS TO SCATTER OUT. VFR CONDITIONS THEN EXPECTED FOR THE REMAINDER OF THE PERIOD WITH SOME GUSTY NORTHWEST WINDS FOR KRST BY MID MORNING SATURDAY. && .HYDROLOGY... ISSUED AT 240 AM CDT FRI MAY 2 2014 RUNOFF FROM RECENT RAIN CONTINUES TO FLOW THROUGH THE MISSISSIPPI RIVER TRIBUTARIES AND THE MAIN CHANNEL. CURRENTLY ONLY THE MISSISSIPPI RIVER AT WABASHA IS IN FLOOD...BUT FORECASTS CONTINUE TO POINT TO THE MISSISSIPPI RIVER AT WINONA...LA CROSSE...MCGREGOR AND GUTTENBERG DAM 10 TO BEGIN MINOR FLOODING IN THE NEXT 1 TO 4.5 DAYS. IN ADDITION...THE BLACK RIVER AT GALESVILLE IS APPROACHING FLOOD STAGE...BUT SHOULD NOT CLIMB MUCH ABOVE MINOR FLOOD WITH FALLING RIVER LEVELS AT BLACK RIVER FALLS. NO MAJOR RAINS ARE ANTICIPATED OVER THE NEXT 5 DAYS SO RUNOFF WILL BE THE MAIN CONTRIBUTING FACTOR TO RIVER LEVELS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04 HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
644 AM CDT FRI MAY 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 240 AM CDT FRI MAY 2 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO BRITISH COLUMBIA...AN UPPER LOW AND SHORTWAVE TROUGH OVER NORTHERN ALBERTA/SASKATCHEWAN... A SHORTWAVE TROUGH OVER SOUTHERN MANITOBA...AND AN ELONGATED LONG WAVE TROUGH FROM TEXAS INTO THE GREAT LAKES. THE FORECAST AREA LIES NOW IN SUBSIDENCE IN THE WAKE OF THE LONG WAVE TROUGH...PROMOTING DRY AIR ADVECTION FROM THE NORTHWEST. THIS CAN BE SEEN BY THE LOW STRATUS DECK CLEARING ACROSS MINNESOTA ON 11-3.9UM IMAGERY AND SURFACE OBSERVATIONS. 00Z BIS AND ABR SOUNDINGS WERE ALSO QUITE DRY WITH PRECIPITABLE WATER OF ONLY 0.3-0.4 INCHES. REPLACING THE STRATUS DECK HAS BEEN MID AND HIGH CLOUDS SPREADING SOUTHEAST ACROSS THE DAKOTAS AND MINNESOTA...AHEAD OF THE SHORTWAVE THERE. GRAND FORKS RADAR DISPLAYING SOME LIGHT RETURNS AS WELL...BUT SO FAR THE DRY AIR HAS BEEN WINNING OUT KEEPING THE PRECIPITATION AS VIRGA. AIRMASS OVER THE FORECAST AT 00Z WAS STILL UNSEASONABLY COOL WITH 925MB TEMPS AROUND 4C...BUT WARMER 9-13C READINGS WERE LURKING UPSTREAM AT ABR AND BIS. BEHIND THE SHORTWAVE TROUGH IN SOUTHERN MANITOBA...SKIES CLEAR OUT AND SURFACE PRESSURES WERE RISING ABOUT 1 MB/HR...PROMOTING GUSTY WINDS ACROSS NORTH DAKOTA. MODELS ARE IN GOOD AGREEMENT DROPPING THE SOUTHERN MANITOBA SHORTWAVE SOUTHEASTWARD THROUGH THE FORECAST AREA THIS AFTERNOON. MORE IMPORTANTLY...THERE IS A CONSISTENT SIGNAL FROM ALL MODELS FOR THE SHORTWAVE TO WEAKEN SOME. THIS WEAKENING COMBINED WITH THE DRY ADVECTION CURRENTLY TAKING PLACE FROM THE NORTHWEST BRINGS IN SOME CONCERN FOR PRECIPITATION CHANCES TODAY. HARD TO FIND A MODEL THAT DOESNT PRECIPITATE WITH THE SHORTWAVE...WHICH MAKES SENSE IN GENERAL GIVEN WE HAVE A SHORTWAVE TROUGH COMING THROUGH AT PEAK HEATING. BETWEEN DYNAMICS AND INSTABILITY FROM HEATING...SHOWERS DEVELOPING IS REASONABLE. HOWEVER...IT IS WORTH NOTING THAT 2 METER DEWPOINT GUIDANCE FROM THE BASE MODELS SUCH AS THE ECMWF...GFS...NAM AND REGIONAL CANADIAN ALL PUSH DEWPOINTS WELL INTO THE 40S...WITH EVEN THE GFS AND REGIONAL CANADIAN APPROACHING 50 BY 00Z. THIS SEEMS A BIT HIGH GIVEN CURRENT SURFACE DEWPOINTS IN THE UPPER 20S TO MID 30S OVER THE DAKOTAS. PERHAPS THE MODELS ARE THINKING GREEN-UP HAS ALREADY TAKEN PLACE BASED ON CLIMATOLOGY. WE DO HAVE WET SOILS SO THAT COULD PROMOTE SLIGHTLY HIGHER DEWPOINTS. IN SUMMARY...FEEL FAIRLY CONFIDENT THAT WE WILL SEE SHOWERS THIS AFTERNOON...BUT A LITTLE LESS CERTAIN ON IF THEY WILL BE WIDESPREAD. ANOTHER CHANGE WORTH NOTING IS THAT THE 02.00Z NAM MUCAPE THIS AFTERNOON HAS DROPPED FROM PREVIOUS RUNS...NOW BELOW 200 J/KG...WHICH MAKES SENSE. CONSIDERED DROPPING THE THUNDER MENTION ENTIRELY AS A RESULT...BUT THE RAP DOES DEPICT A ZONE OF 700-500MB LAPSE RATES APPROACHING 7 C/KM OVER THE FORECAST AREA DURING THE AFTERNOON. THEREFORE...HAVE LEFT THE THUNDER IN THE FORECAST FOR THE AFTERNOON. ANY SHOWER ACTIVITY SHOULD QUICKLY EXIT THE AREA BETWEEN 00-03Z WITH THE SHORTWAVE EXITING AND DIURNAL COOLING. AS WE APPROACH LATE TONIGHT...MORE SHOWER ACTIVITY LOOKS TO DROP DOWN INTO NORTHERN MN AND WI. THESE ARE AHEAD OF THE SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN... PROGGED TO BE OVER SOUTHERN MANITOBA AND NORTHERN MN BY 12Z SATURDAY. ITS POSSIBLE THIS SHOWER ACTIVITY COULD GET INTO TAYLOR COUNTY TOWARDS 12Z...BUT FOR NOW HAVE KEPT THE FORECAST DRY. 925MB TEMPERATURES ARE PROGGED A FEW DEGREES WARMER TODAY...BETWEEN 6-8C FOR THE AFTERNOON HOURS. THERE IS A CHANCE WE CAN SNEAK IN A LITTLE SUN AND WITH A WARM ADVECTING SOUTHWEST WIND...MOST LOCATIONS WILL CLIMB INTO THE 50S. THERES EVEN A CHANCE SOME SPOTS COULD PUSH 60...SUCH AS CHARLES CITY...WINONA...LA CROSSE AND BOSCOBEL. THIS ALL HINGES IF WE CAN GET MORE SUN...BUT THINK OVERALL WE WILL BE CLOUDY OR MOSTLY CLOUDY TODAY. COLD ADVECTION TONIGHT ON A NORTHWEST WIND...WHICH COULD BE BRISK IN THE EVENING WEST OF THE MS RIVER WITH THE PRESSURE RISE COMING THROUGH...WILL ALLOW TEMPERATURES TO DROP INTO THE 30S TO LOW 40S TONIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 240 AM CDT FRI MAY 2 2014 UPPER LEVEL PATTERN CHANGE REMAINS ON TRACK DURING THE LONG TERM PERIOD...WITH UPPER RIDGING CURRENTLY OVER THE WESTERN U.S. PROGGED TO BUILD OVER THE REGION LATE TUESDAY INTO WEDNESDAY. THIS IS ALL IN RESPONSE TO AN UPPER LOW CURRENTLY OFF THE PACIFIC NORTHWEST COAST SUGGESTED TO DIG INTO THE SOUTHWESTERN U.S.. THIS PATTERN CHANGE MEANS A GRADUAL MODERATION OF TEMPERATURES...ALONG WITH POTENTIAL FOR MORE ACTIVE WEATHER AS WE APPROACH THE MIDDLE OF NEXT WEEK. FIRST OFF...SATURDAY. THAT NEXT SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN WILL SLIDE ACROSS NORTHERN PORTIONS OF MN AND WI...ALONG WITH UPPER MI AND ONTARIO DURING THE DAY AND EVENING HOURS. THIS TRACK KEEPS THE BEST DPVA FORCING NORTH OF THE FORECAST AREA. THEREFORE...THINK MUCH OF THE PRECIPITATION WILL STAY NORTH AS WELL. HOWEVER...THERE WILL BE A SURFACE COLD FRONT ACCOMPANYING THE SHORTWAVE. THE 02.00Z GFS PRINTS OUT SOME LIGHT QPF OVER LA CROSSE AS THE FRONT COMES THROUGH... MOSTLY A RESULT OF THE MODEL DEVELOPING SOME WEAK CAPE. BELIEVE THE MODEL IS TOO FAR SOUTH AND OVERLY MOIST. HAVE DECIDED TO KEEP ANY LOW CHANCES OF PRECIPITATION NORTH OF I-94...CONSISTENT TOO WITH THE 02.00Z ECMWF. 925MB TEMPS REBOUND DECENTLY ON SATURDAY...6-9C... ALLOWING TEMPERATURES TO CLIMB SLIGHTLY HIGHER THAN THOSE TODAY. NEXT UP IS ON SUNDAY WHERE THE 02.00Z GFS/CANADIAN/ECMWF/NAM ALL DEVELOP A FRONTOGENETICAL BAND OF PRECIPITATION. THE BAND ALSO HAS SOME RIGHT ENTRANCE REGION FORCING FROM A JET STREAK FOLLOWING THE SATURDAY SHORTWAVE TROUGH. THE NAM IS THE ODD MODEL OUT ON LOCATION OF THE BAND...TRACKING IT FROM MINNEAPOLIS TO LA CROSSE AND THE DELLS...WHEREAS ALL OTHER MODELS SUGGEST SOUTHWEST MN INTO NORTHERN IA AND NORTHERN IL AS THE MORE LIKELY TRACK. GIVEN GOOD AGREEMENT ON THIS FRONTOGENETIC BAND FROM THE OTHER MODELS...HAVE RAISED PRECIPITATION CHANCES. MODEL CONSENSUS SUGGESTS 12-18Z SUNDAY IS THE MOST LIKELY TIME PERIOD FOR PRECIPITATION WITH THE PRECIPITATION EXITING RAPIDLY TO THE SOUTHEAST IN THE AFTERNOON. THERE IS SOME LOWER LEVEL DRY AIR PRESENT...WHICH IF THE PRECIPITATION WAS HEAVIER MIGHT CAUSE PRECIPITATION TYPE ISSUES FROM EVAPORATIVE COOLING. FOR NOW WILL KEEP THE PRECIPITATION TYPE AS RAIN GIVEN GENERALLY LIGHT QPF PROGGED BUT SOMETHING TO WATCH. WITH THIS FRONTOGENETICAL BAND GOING THROUGH AND A NORTHEAST BREEZE...TEMPERATURES ARE GOING TO TAKE A COOL DOWN. THIS IS ESPECIALLY TRUE UNDER THE PRECIPITATION. RAIN CHANCES COME BACK FOR MONDAY WHEN YET ANOTHER BAND OF FRONTOGENESIS AND ISENTROPIC LIFT MOVES ACROSS. THIS ONE LOOKS WEAKER THAN ON SUNDAY...THUS 02.00Z GFS/CANADIAN/ECMWF QPF IS LIGHTER AND MORE SPREAD OUT ACROSS THE FORECAST AREA. CONSENSUS 20 PERCENT CHANCES SEEM REASONABLE. COOLED HIGHS SLIGHTLY FROM THE PREVIOUS FORECAST DUE TO CLOUDS AND AN EAST WIND AROUND HIGH PRESSURE IN UPPER MI. THESE COULD NEED FURTHER COOLING IF A LITTLE MORE PRECIPITATION IS AROUND AS SUGGESTED BY THE 02.00Z ECMWF. AS THE UPPER RIDGE BUILDS INTO THE AREA LATE TUESDAY AND ESPECIALLY WEDNESDAY...THAT IS WHEN SOME BIGGER TEMPERATURE CHANGES TAKE PLACE...ALONG WITH INCREASING CONCERNS FOR CONVECTION AND POSSIBLE SEVERE WEATHER. 02.00Z GFS/ECMWF SUGGEST THAT BETWEEN 12Z WEDNESDAY AND 00Z THURSDAY...925MB TEMPS COULD CLIMB AS MUCH AS 10-15C RESULTING IN AN ALMOST SUMMER-LIKE AIRMASS COMING INTO LOCATIONS ALONG AND SOUTH OF I-90. WE WILL HAVE TO WAIT AND SEE HOW THIS PANS OUT. IN ANY EVENT...HAVE FOLLOWED CONSENSUS WITH 30-50 PERCENT CHANCES FOR TUESDAY NIGHT AND WEDNESDAY...WITH SLIGHTLY HIGHER CHANCES FOR WEDNESDAY NIGHT INTO THURSDAY RESULTING FROM A SHORTWAVE TROUGH COMING THROUGH THE UPPER MIDWEST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 644 AM CDT FRI MAY 2 2014 THE MVFR CEILINGS ACROSS WEST-CENTRAL...CENTRAL...AND SOUTHWEST WISCONSIN AND PARTS OF NORTHEAST IOWA WILL BECOME VFR BETWEEN 02.13Z AND 02.15Z....AND THEN REMAIN VFR THROUGH THE REMAINDER OF THE PERIOD. A BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE THROUGH THE TAF SITES BETWEEN 02.18Z AND 03.02Z. THESE SHOWERS MAY BRIEFLY PRODUCE MVFR VISIBILITIES. AS THE COLD FRONT MOVES THROUGH THE AREA THIS EVENING...THE WINDS WILL SHIFT TO NORTHWEST. THIS WILL OCCUR AT KRST AROUND 03.02Z AND KLSE AROUND 03.03Z. SKIES WILL CLEAR ABOUT 2 TO 3 HOURS AFTER THE FRONTAL PASSAGE. && .HYDROLOGY... ISSUED AT 240 AM CDT FRI MAY 2 2014 RUNOFF FROM RECENT RAIN CONTINUES TO FLOW THROUGH THE MISSISSIPPI RIVER TRIBUTARIES AND THE MAIN CHANNEL. CURRENTLY ONLY THE MISSISSIPPI RIVER AT WABASHA IS IN FLOOD...BUT FORECASTS CONTINUE TO POINT TO THE MISSISSIPPI RIVER AT WINONA...LA CROSSE...MCGREGOR AND GUTTENBERG DAM 10 TO BEGIN MINOR FLOODING IN THE NEXT 1 TO 4.5 DAYS. IN ADDITION...THE BLACK RIVER AT GALESVILLE IS APPROACHING FLOOD STAGE...BUT SHOULD NOT CLIMB MUCH ABOVE MINOR FLOOD WITH FALLING RIVER LEVELS AT BLACK RIVER FALLS. NO MAJOR RAINS ARE ANTICIPATED OVER THE NEXT 5 DAYS SO RUNOFF WILL BE THE MAIN CONTRIBUTING FACTOR TO RIVER LEVELS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
240 AM CDT FRI MAY 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 240 AM CDT FRI MAY 2 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S. INTO BRITISH COLUMBIA...AN UPPER LOW AND SHORTWAVE TROUGH OVER NORTHERN ALBERTA/SASKATCHEWAN... A SHORTWAVE TROUGH OVER SOUTHERN MANITOBA...AND AN ELONGATED LONG WAVE TROUGH FROM TEXAS INTO THE GREAT LAKES. THE FORECAST AREA LIES NOW IN SUBSIDENCE IN THE WAKE OF THE LONG WAVE TROUGH...PROMOTING DRY AIR ADVECTION FROM THE NORTHWEST. THIS CAN BE SEEN BY THE LOW STRATUS DECK CLEARING ACROSS MINNESOTA ON 11-3.9UM IMAGERY AND SURFACE OBSERVATIONS. 00Z BIS AND ABR SOUNDINGS WERE ALSO QUITE DRY WITH PRECIPITABLE WATER OF ONLY 0.3-0.4 INCHES. REPLACING THE STRATUS DECK HAS BEEN MID AND HIGH CLOUDS SPREADING SOUTHEAST ACROSS THE DAKOTAS AND MINNESOTA...AHEAD OF THE SHORTWAVE THERE. GRAND FORKS RADAR DISPLAYING SOME LIGHT RETURNS AS WELL...BUT SO FAR THE DRY AIR HAS BEEN WINNING OUT KEEPING THE PRECIPITATION AS VIRGA. AIRMASS OVER THE FORECAST AT 00Z WAS STILL UNSEASONABLY COOL WITH 925MB TEMPS AROUND 4C...BUT WARMER 9-13C READINGS WERE LURKING UPSTREAM AT ABR AND BIS. BEHIND THE SHORTWAVE TROUGH IN SOUTHERN MANITOBA...SKIES CLEAR OUT AND SURFACE PRESSURES WERE RISING ABOUT 1 MB/HR...PROMOTING GUSTY WINDS ACROSS NORTH DAKOTA. MODELS ARE IN GOOD AGREEMENT DROPPING THE SOUTHERN MANITOBA SHORTWAVE SOUTHEASTWARD THROUGH THE FORECAST AREA THIS AFTERNOON. MORE IMPORTANTLY...THERE IS A CONSISTENT SIGNAL FROM ALL MODELS FOR THE SHORTWAVE TO WEAKEN SOME. THIS WEAKENING COMBINED WITH THE DRY ADVECTION CURRENTLY TAKING PLACE FROM THE NORTHWEST BRINGS IN SOME CONCERN FOR PRECIPITATION CHANCES TODAY. HARD TO FIND A MODEL THAT DOESNT PRECIPITATE WITH THE SHORTWAVE...WHICH MAKES SENSE IN GENERAL GIVEN WE HAVE A SHORTWAVE TROUGH COMING THROUGH AT PEAK HEATING. BETWEEN DYNAMICS AND INSTABILITY FROM HEATING...SHOWERS DEVELOPING IS REASONABLE. HOWEVER...IT IS WORTH NOTING THAT 2 METER DEWPOINT GUIDANCE FROM THE BASE MODELS SUCH AS THE ECMWF...GFS...NAM AND REGIONAL CANADIAN ALL PUSH DEWPOINTS WELL INTO THE 40S...WITH EVEN THE GFS AND REGIONAL CANADIAN APPROACHING 50 BY 00Z. THIS SEEMS A BIT HIGH GIVEN CURRENT SURFACE DEWPOINTS IN THE UPPER 20S TO MID 30S OVER THE DAKOTAS. PERHAPS THE MODELS ARE THINKING GREEN-UP HAS ALREADY TAKEN PLACE BASED ON CLIMATOLOGY. WE DO HAVE WET SOILS SO THAT COULD PROMOTE SLIGHTLY HIGHER DEWPOINTS. IN SUMMARY...FEEL FAIRLY CONFIDENT THAT WE WILL SEE SHOWERS THIS AFTERNOON...BUT A LITTLE LESS CERTAIN ON IF THEY WILL BE WIDESPREAD. ANOTHER CHANGE WORTH NOTING IS THAT THE 02.00Z NAM MUCAPE THIS AFTERNOON HAS DROPPED FROM PREVIOUS RUNS...NOW BELOW 200 J/KG...WHICH MAKES SENSE. CONSIDERED DROPPING THE THUNDER MENTION ENTIRELY AS A RESULT...BUT THE RAP DOES DEPICT A ZONE OF 700-500MB LAPSE RATES APPROACHING 7 C/KM OVER THE FORECAST AREA DURING THE AFTERNOON. THEREFORE...HAVE LEFT THE THUNDER IN THE FORECAST FOR THE AFTERNOON. ANY SHOWER ACTIVITY SHOULD QUICKLY EXIT THE AREA BETWEEN 00-03Z WITH THE SHORTWAVE EXITING AND DIURNAL COOLING. AS WE APPROACH LATE TONIGHT...MORE SHOWER ACTIVITY LOOKS TO DROP DOWN INTO NORTHERN MN AND WI. THESE ARE AHEAD OF THE SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN... PROGGED TO BE OVER SOUTHERN MANITOBA AND NORTHERN MN BY 12Z SATURDAY. ITS POSSIBLE THIS SHOWER ACTIVITY COULD GET INTO TAYLOR COUNTY TOWARDS 12Z...BUT FOR NOW HAVE KEPT THE FORECAST DRY. 925MB TEMPERATURES ARE PROGGED A FEW DEGREES WARMER TODAY...BETWEEN 6-8C FOR THE AFTERNOON HOURS. THERE IS A CHANCE WE CAN SNEAK IN A LITTLE SUN AND WITH A WARM ADVECTING SOUTHWEST WIND...MOST LOCATIONS WILL CLIMB INTO THE 50S. THERES EVEN A CHANCE SOME SPOTS COULD PUSH 60...SUCH AS CHARLES CITY...WINONA...LA CROSSE AND BOSCOBEL. THIS ALL HINGES IF WE CAN GET MORE SUN...BUT THINK OVERALL WE WILL BE CLOUDY OR MOSTLY CLOUDY TODAY. COLD ADVECTION TONIGHT ON A NORTHWEST WIND...WHICH COULD BE BRISK IN THE EVENING WEST OF THE MS RIVER WITH THE PRESSURE RISE COMING THROUGH...WILL ALLOW TEMPERATURES TO DROP INTO THE 30S TO LOW 40S TONIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 240 AM CDT FRI MAY 2 2014 UPPER LEVEL PATTERN CHANGE REMAINS ON TRACK DURING THE LONG TERM PERIOD...WITH UPPER RIDGING CURRENTLY OVER THE WESTERN U.S. PROGGED TO BUILD OVER THE REGION LATE TUESDAY INTO WEDNESDAY. THIS IS ALL IN RESPONSE TO AN UPPER LOW CURRENTLY OFF THE PACIFIC NORTHWEST COAST SUGGESTED TO DIG INTO THE SOUTHWESTERN U.S.. THIS PATTERN CHANGE MEANS A GRADUAL MODERATION OF TEMPERATURES...ALONG WITH POTENTIAL FOR MORE ACTIVE WEATHER AS WE APPROACH THE MIDDLE OF NEXT WEEK. FIRST OFF...SATURDAY. THAT NEXT SHORTWAVE TROUGH AND UPPER LOW CURRENTLY IN NORTHERN ALBERTA/SASKATCHEWAN WILL SLIDE ACROSS NORTHERN PORTIONS OF MN AND WI...ALONG WITH UPPER MI AND ONTARIO DURING THE DAY AND EVENING HOURS. THIS TRACK KEEPS THE BEST DPVA FORCING NORTH OF THE FORECAST AREA. THEREFORE...THINK MUCH OF THE PRECIPITATION WILL STAY NORTH AS WELL. HOWEVER...THERE WILL BE A SURFACE COLD FRONT ACCOMPANYING THE SHORTWAVE. THE 02.00Z GFS PRINTS OUT SOME LIGHT QPF OVER LA CROSSE AS THE FRONT COMES THROUGH... MOSTLY A RESULT OF THE MODEL DEVELOPING SOME WEAK CAPE. BELIEVE THE MODEL IS TOO FAR SOUTH AND OVERLY MOIST. HAVE DECIDED TO KEEP ANY LOW CHANCES OF PRECIPITATION NORTH OF I-94...CONSISTENT TOO WITH THE 02.00Z ECMWF. 925MB TEMPS REBOUND DECENTLY ON SATURDAY...6-9C... ALLOWING TEMPERATURES TO CLIMB SLIGHTLY HIGHER THAN THOSE TODAY. NEXT UP IS ON SUNDAY WHERE THE 02.00Z GFS/CANADIAN/ECMWF/NAM ALL DEVELOP A FRONTOGENETICAL BAND OF PRECIPITATION. THE BAND ALSO HAS SOME RIGHT ENTRANCE REGION FORCING FROM A JET STREAK FOLLOWING THE SATURDAY SHORTWAVE TROUGH. THE NAM IS THE ODD MODEL OUT ON LOCATION OF THE BAND...TRACKING IT FROM MINNEAPOLIS TO LA CROSSE AND THE DELLS...WHEREAS ALL OTHER MODELS SUGGEST SOUTHWEST MN INTO NORTHERN IA AND NORTHERN IL AS THE MORE LIKELY TRACK. GIVEN GOOD AGREEMENT ON THIS FRONTOGENETIC BAND FROM THE OTHER MODELS...HAVE RAISED PRECIPITATION CHANCES. MODEL CONSENSUS SUGGESTS 12-18Z SUNDAY IS THE MOST LIKELY TIME PERIOD FOR PRECIPITATION WITH THE PRECIPITATION EXITING RAPIDLY TO THE SOUTHEAST IN THE AFTERNOON. THERE IS SOME LOWER LEVEL DRY AIR PRESENT...WHICH IF THE PRECIPITATION WAS HEAVIER MIGHT CAUSE PRECIPITATION TYPE ISSUES FROM EVAPORATIVE COOLING. FOR NOW WILL KEEP THE PRECIPITATION TYPE AS RAIN GIVEN GENERALLY LIGHT QPF PROGGED BUT SOMETHING TO WATCH. WITH THIS FRONTOGENETICAL BAND GOING THROUGH AND A NORTHEAST BREEZE...TEMPERATURES ARE GOING TO TAKE A COOL DOWN. THIS IS ESPECIALLY TRUE UNDER THE PRECIPITATION. RAIN CHANCES COME BACK FOR MONDAY WHEN YET ANOTHER BAND OF FRONTOGENESIS AND ISENTROPIC LIFT MOVES ACROSS. THIS ONE LOOKS WEAKER THAN ON SUNDAY...THUS 02.00Z GFS/CANADIAN/ECMWF QPF IS LIGHTER AND MORE SPREAD OUT ACROSS THE FORECAST AREA. CONSENSUS 20 PERCENT CHANCES SEEM REASONABLE. COOLED HIGHS SLIGHTLY FROM THE PREVIOUS FORECAST DUE TO CLOUDS AND AN EAST WIND AROUND HIGH PRESSURE IN UPPER MI. THESE COULD NEED FURTHER COOLING IF A LITTLE MORE PRECIPITATION IS AROUND AS SUGGESTED BY THE 02.00Z ECMWF. AS THE UPPER RIDGE BUILDS INTO THE AREA LATE TUESDAY AND ESPECIALLY WEDNESDAY...THAT IS WHEN SOME BIGGER TEMPERATURE CHANGES TAKE PLACE...ALONG WITH INCREASING CONCERNS FOR CONVECTION AND POSSIBLE SEVERE WEATHER. 02.00Z GFS/ECMWF SUGGEST THAT BETWEEN 12Z WEDNESDAY AND 00Z THURSDAY...925MB TEMPS COULD CLIMB AS MUCH AS 10-15C RESULTING IN AN ALMOST SUMMER-LIKE AIRMASS COMING INTO LOCATIONS ALONG AND SOUTH OF I-90. WE WILL HAVE TO WAIT AND SEE HOW THIS PANS OUT. IN ANY EVENT...HAVE FOLLOWED CONSENSUS WITH 30-50 PERCENT CHANCES FOR TUESDAY NIGHT AND WEDNESDAY...WITH SLIGHTLY HIGHER CHANCES FOR WEDNESDAY NIGHT INTO THURSDAY RESULTING FROM A SHORTWAVE TROUGH COMING THROUGH THE UPPER MIDWEST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1110 PM CDT THU MAY 1 2014 THE MVFR CLOUD DECK HAS BEEN WORKING STEADILY EAST THIS EVENING AS THE STORM SYSTEM THAT PLAGUED THE AREA THE PAST FEW DAYS CONTINUES TO MOVE AWAY FROM THE REGION. THESE MVFR CLOUDS HAVE ALREADY MOVED EAST OF KRST AND WILL DO THE SAME AT KLSE BY 09Z OR 10Z. EXPECT THAT THE CEILINGS WILL POP UP TO AROUND 10 THOUSAND FEET OR SO FOR A SHORT PERIOD FRIDAY MORNING AHEAD OF THE NEXT SYSTEM THAT IS ALREADY QUICKLY APPROACHING FROM THE NORTHWEST. THIS SHORT WAVE TROUGH IS SHOWN BY THE 02.00Z NAM TO MOVE ACROSS THE REGION FRIDAY AFTERNOON BUT LOOKS TO BE WEAKENING AS IT DOES...WHICH IS SHOWN BY THE DIMINISHING PV ADVECTION SIGNAL IN THE 500-300 MB LAYER. EARLIER RUNS HAD SUGGESTED THAT THE LEFT EXIT REGION OF THE 300 MB JET WOULD ACCOMPANY THE SHORT WAVE TROUGH...BUT THE NAM HAS BACKED AWAY FROM THIS HOLDING THE JET BACK UNTIL THE NEXT SYSTEM COMES OUT OF CANADA FOR SATURDAY. THE DEEPEST MOISTURE LOOKS TO BE OVER WISCONSIN WITH NOT MUCH OF SIGNAL FOR MOISTURE TO RETURN WITH JUST A WEAK MOISTURE TRANSPORT SIGNAL OFF THE THE HIGH PLAINS AND NOT FROM THE GULF REGION. THE NAM ALSO SHOWS LESS CAPE THAN PREVIOUS RUNS WITH LESS THAN 100 J/KG OF ML CAPE AND ONLY AROUND 200 J/KG OF MU CAPE. HAVE STAYED WITH THE IDEA OF JUST SHOWING SOME VICINITY SHOWERS FOR BOTH TAF SITES FRIDAY AFTERNOON AS EXPECTING THE BETTER COVERAGE TO BE TO THE EAST. WITH THE LIMITED CAPE...DID NOT INTRODUCE ANY THUNDER EITHER. THE THREAT FOR SHOWERS SHOULD END LATE IN THE AFTERNOON OR EARLY IN THE EVENING WITH SUBSIDENCE SETTING IN ALLOWING THE CLOUDS TO SCATTER OUT. && .HYDROLOGY... ISSUED AT 240 AM CDT FRI MAY 2 2014 RUNOFF FROM RECENT RAIN CONTINUES TO FLOW THROUGH THE MISSISSIPPI RIVER TRIBUTARIES AND THE MAIN CHANNEL. CURRENTLY ONLY THE MISSISSIPPI RIVER AT WABASHA IS IN FLOOD...BUT FORECASTS CONTINUE TO POINT TO THE MISSISSIPPI RIVER AT WINONA...LA CROSSE...MCGREGOR AND GUTTENBERG DAM 10 TO BEGIN MINOR FLOODING IN THE NEXT 1 TO 4.5 DAYS. IN ADDITION...THE BLACK RIVER AT GALESVILLE IS APPROACHING FLOOD STAGE...BUT SHOULD NOT CLIMB MUCH ABOVE MINOR FLOOD WITH FALLING RIVER LEVELS AT BLACK RIVER FALLS. NO MAJOR RAINS ARE ANTICIPATED OVER THE NEXT 5 DAYS SO RUNOFF WILL BE THE MAIN CONTRIBUTING FACTOR TO RIVER LEVELS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04 HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS DES MOINES IA
329 AM CDT SUN MAY 4 2014 .SHORT TERM /TODAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST CONCERN FOR TODAY WILL BE PRECIPITATION CHANCES IN THE MORNING HOURS. CURRENTLY...PRECIPITATION IS BEGINNING TO FILL IN AND EXPAND IN CENTRAL SD/NORTHERN NE AS SHORTWAVE PUSHES SE. HIGH RES MODELS HAVE THE BEST HANDLE ON ONGOING PRECIPITATION...AND HAVE TRENDED TOWARDS HRRR AND CONSSHORT AND HAVE EXTENDED POPS FURTHER SOUTH AND WEST. HOWEVER...HAVE NOT BEEN AS AGGRESSIVE AS MODELS INDICATE GIVEN LARGE AMOUNT OF LOW LEVEL DRY AIR. SOUNDINGS STILL INDICATING MOISTURE SOMEWHAT LACKING IN CENTRAL CWA. THEREFORE...HAVE ALSO KEPT PRECIP MENTION SCATTERED/ISOLATED. SYSTEM WILL PUSH QUICKLY EAST/NORTHEAST WITH DRY CONDITIONS IN STORE FOR REMAINDER OF AFTERNOON AS WEAK RIDGE PUSHES IN. HAVE INCREASED TEMPERATURES WITH DECENT WAA...ESPECIALLY IN THE SOUTH. .LONG TERM /TONIGHT THROUGH FRIDAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 LONG TERM FORECAST WILL BE DOMINATED BY LARGE WESTERN TROF THAT EVENTUALLY TRACKS EASTWARD THROUGH THE REGION BY LATE IN THE WORK WEEK. PRIOR TO THE ARRIVAL HOWEVER...THE WEATHER WILL BE RELATIVELY TRANQUIL FROM TONIGHT INTO TUESDAY. SURFACE BOUNDARY WILL SET UP ACROSS MISSOURI DURING THIS TIME WITH DRY EASTERLY LOW-LEVEL FLOW ACROSS IOWA. WILL SEE WARM ADVECTION GETTING PROGRESSIVELY STRONGER THROUGH MONDAY INTO TUESDAY WITH HIGHS BY TUESDAY AFTERNOON GETTING CLOSE TO NORMAL. FRONT WILL BEGIN TO LIFT NORTHWARD INTO THE STATE TUESDAY NIGHT INTO WEDNESDAY IN RESPONSE TO DEVELOPING SURFACE LOW ACROSS THE PLAINS. INCREASING THETA-E ADVECTION ON TUESDAY NIGHT SHOULD LEAD TO DEVELOPMENT OF SCATTERED CONVECTION IN NORTHERN IOWA LATE. THIS CONVECTION MAY LINGER INTO WEDNESDAY MORNING IN THE FAR NORTH AS THERMAL RIDGE BUILDS INTO THE STATE. BY WEDNESDAY AFTERNOON... HIGHS WELL INTO THE 80S ARE EXPECTED WITH DEEP MIXING AND STRONG SOUTHERLY FLOW INTO THE STATE. WHILE SOME CONVECTION WILL OCCUR ON WEDNESDAY NIGHT...IT IS LIKELY THE BULK OF ANY PRECIPITATION WILL BE NORTHWEST OF THE FORECAST AREA CLOSER TO THE SURFACE BOUNDARY. THIS BOUNDARY WILL SAG INTO STATE ON THURSDAY WITH CONVECTION LIKELY TO BECOME WIDESPREAD BY AFTERNOON IN MOST LOCATIONS. A FEW SEVERE STORMS WILL ALSO BE POSSIBLE WITH THIS CONVECTION. THE STORMS ARE EXPECTED TO CONTINUE INTO THURSDAY NIGHT BUT WITH PROGRESSION TO THE EAST AS THE BOUNDARY SLIDES THROUGH THE STATE. SOME LINGERING PCPN IS FORECAST ON FRIDAY BEFORE ENDING WITH DRIER CONDITIONS INTO FRIDAY NIGHT. && .AVIATION...04/06Z ISSUED AT 1145 PM CDT SAT MAY 3 2014 SOME MID CLOUDS STREAMING ACROSS THE NORTHERN TAF SITES...WITH CLOUDS EXPECTED TO INCREASE ACROSS THE NORTH TOWARD 12Z WITH SOME LIGHT SHOWERS POSSIBLE AT KMCW AND KALO. STILL EXPECT MAJORITY OF ACTIVITY TO STAY NORTH AND EAST OF KFOD. WINDS TO SHIFT AROUND TO THE EAST THROUGH THE PERIOD. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...AWB LONG TERM...COGIL AVIATION...BEERENDS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1144 PM CDT SAT MAY 3 2014 .UPDATE... ISSUED AT 543 PM CDT SAT MAY 3 2014 BASED ON RADAR AND OBS I HAVE UPDATED FORECAST TO RAISE POPS ACROSS W/SW PORTIONS OF CWA INTO EARLY EVE FOR BAND OF SHOWERS ATTENDANT TO MID LEVEL FRONTOGENETICAL FORCING. WITH CONSIDERABLE T/TD SPREADS NOT EXPECTING MUCH MORE THAN A TRACE TO A COUPLE HUNDREDTHS OF AN INCH. && .SYNOPSIS... ISSUED AT 312 PM CDT SAT MAY 3 2014 SPRAWLING LOW PRESSURE OVER HUDSON BAY WAS PROVIDING THE MID MISSISSIPPI VALLEY WITH A BREEZY AND RELATIVELY MILD SATURDAY. FOR THE MOST PART THE REGION WAS DRY WITH THE EXCEPTION OF A NARROW BAND OF RAIN FROM SOUTHEAST SOUTH DAKOTA INTO SOUTH CENTRAL IOWA. THE RAIN WAS COMING FROM A MID CLOUD DECK WITH A DEEP AND DRY SUB CLOUD LAYER WHICH WAS CAUSING MOST OF THE RAIN TO EVAPORATE BEFORE REACHING THE GROUND. THE RAIN AND MID CLOUDS WERE OCCURRING IN A REGION OF MID LEVEL FGEN ON THE SOUTHWEST FLANK OF A 120KT H3 JET STREAK OVER THE NORTH CENTRAL U.S. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 312 PM CDT SAT MAY 3 2014 THE REGION WILL REMAIN IN NORTHWEST FLOW THROUGH SUNDAY AS AN UPPER RIDGE MOVES INTO THE HIGH PLAINS AND AN UPPER LOW OVER ONTARIO WEAKENS. AS THE UPPER RIDGE MOVES EAST...SURFACE HIGH PRESSURE WILL BUILD INTO THE WESTERN GREAT LAKES WHILE A WARM FRONT SETS UP FROM CENTRAL PLAINS INTO THE LOWER OHIO VALLEY. THE FIRST CONCERN WILL BE THE HIGH BASED RAIN OVER THE WESTERN HALF OF IOWA. THE HRRR HAS BEEN CONSISTENT IN BRINGING THE RAIN ACROSS THE DVN CWFA LATE THIS AFTERNOON AND EARLY THIS EVENING. HOWEVER THE HRRR HAS ALSO BEEN CONSISTENTLY TO FAR NORTHEAST WITH THE PRECIPITATION. ALSO THE RAIN SEEMS TO CORRELATE WELL WITH FGEN IN THE 700-500MB LAYER WHICH THE RAP SHOWS WEAKENING WITH TIME. FOR NOW WILL GO WITH SOME SPRINKLES IN THE SOUTH THIS EVENING...THINKING THAT MOST OF THE PRECIPITATION WILL DISSIPATE BEFORE REACHING THE GROUND. LATER TONIGHT AND SUNDAY MORNING MODELS SHOW THE RIGHT ENTRANCE REGION OF THE NORTH CENTRAL U.S. H3 JET MOVING THROUGH THE REGION. MID/LOW LEVEL FGEN AND UPPER DIVERGENCE ASSOCIATED WITH THE JET ARE PROGGED TO SUPPORT ANOTHER BAND OF RAIN THAT SHOULD IMPACT AREAS MAINLY NORTH OF I80 SUNDAY MORNING. GIVEN THE CONSISTENCY BETWEEN THE MODELS WITH THIS FEATURE...HAVE INCREASED POPS TO LIKELY FOR AREAS MAINLY NORTH OF HIGHWAY 30. THE RAIN SHOULD BE EAST OF THE FORECAST AREA BY EARLY AFTERNOON WITH DRY WEATHER EXPECTED THE REST OF THE DAY. WITH INCREASING MID CLOUDS OVERNIGHT TONIGHT TEMPERATURES WERE KEPT ON THE MILDER SIDE OF GUIDANCE MAINLY IN THE 40S. SUNDAY WITH THE SURFACE HIGH SETTING UP TO OUR NORTH AND THE DEVELOPING WARM FRONT SOUTH...A DECENT THERMAL GRADIENT WILL DEVELOP ACROSS THE REGION. HIGHS SHOULD RANGE FROM NEAR 70 IN THE FAR SOUTH TO THE MIDDLE 50S NORTH. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 312 PM CDT SAT MAY 3 2014 FORECAST FOCUS IS ON WELCOMED WARMING TREND NEXT WEEK AND ON PCPN CHANCES MID TO LATE WEEK. SUNDAY NIGHT...WEAK DISTURBANCE TO HAVE EXITED THE AREA WITH HIGH PRESSURE BUILDING INTO THE GREAT LAKES REGION. WITH A STATIONARY BOUNDARY WELL TO OUR SOUTH AND EASTERLY FLOW OFF THE GREAT LAKES... WILL SEE TEMPS DROP INTO THE UPPER 30S/LOW 40S UNDER PARTLY CLOUDY SKIES. MONDAY-TUESDAY...EASTERLY LOW LEVEL FLOW AND SOME MID-HIGH LEVEL CLOUDS WILL BE THE NORM AS HIGH PRESSURE DRIFTS OVER THE GREAT LAKES AND A FRONTAL BOUNDARY REMAINS SOUTH OF THE AREA DRAPED OVER MISSOURI AND SOUTHERN ILLINOIS. HIGHS WILL REACH THE LOWER 60S NORTH TO LOWER 70S IN THE FAR SOUTH WHICH IS NEAR NORMAL FOR EARLY MAY. TUESDAY NIGHT-WEDNESDAY...WARM FRONT PROGGED TO LIFT NORTH INTO NORTHEAST IOWA AND SOUTHERN WISCONSIN BY EARLY EVENING WEDNESDAY. CONVERGENCE ALONG THE FRONT COUPLED WITH A 40KT LLJ SHOULD ALLOW FOR SOME OVERNIGHT ELEVATED SHOWERS AND THUNDERSTORMS TO DEVELOP MAINLY ACROSS THE NORTHERN HALF OF THE CWA. MUCAPES BETWEEN 1500-2000 J/KG AND PROGGED 40KT 0-6KM SHEAR VALUES SUGGEST SMALL SEVERE THREAT WITH ANY STRONG STORM THAT WOULD DEVELOP TO PRODUCE MARGINAL SEVERE HAIL. OVERNIGHT LOW TEMPERATURES WILL DEPEND LARGELY ON SPEED OF WARM FRONT LIFTING NORTH. FOR NOW WILL GO WITH LOWER 50S NORTH TO THE LOWER 60S SOUTH. CWA TO BE COMPLETELY IN THE WARM SECTOR BY WEDNESDAY AFTERNOON WITH TEMPERATURES SOARING INTO THE UPPER 70S/MIDDLE 80S AND A STRONG CAP IN PLACE OVER THE AREA. IT WILL ALSO FEEL HUMID...WITH DEWPOINTS IN THE UPPER 50S AND LOWER 60S. WEDNESDAY NIGHT...STRONG LLJ TO ONCE AGAIN DEVELOP OVERNIGHT OVER THE PLAINS WITH STORMS DEVELOPING ON THE NOSE OF JET ACROSS CENTRAL IOWA. LATEST MODELS TRACK THESE STORMS EAST AND WEAKEN AS THEY NEAR THE CWA. NONETHELESS HAVE MAINTAINED HIGH CHANCE POPS ACROSS THE WEST FOR THIS BUT MAY NEED TO BE LOWERED IF MODELS CONTINUE TO SHOW WEAKER FORCING. STEEP MID LEVEL LAPSE RATES ALSO SUGGEST A FEW RUMBLES OF THUNDER WILL BE POSSIBLE AS WELL. TEMPERATURES WILL BE VERY MILD WEDNESDAY NIGHT DUE TO REGION IN THE WARM SECTOR WITH LOWS ONLY DROPPING INTO THE LOWER 60S. THURSDAY...WARM AND HUMID CONDITIONS WILL BE COMMON AS STRONG SOUTHERLY FLOW CONTINUES AHEAD OF SURFACE LOW IN THE PLAINS. LATEST 12Z MODEL SUITE HAS SLOWED THE PROGRESSION OF THE COLD FRONT SOME WITH IT NOT ARRIVING INTO THE WESTERN PART OF THE CWA UNTIL EARLY FRIDAY. THIS SLOWER FRONT WILL HELP BOOST TEMPERATURES AND HAVE RAISED READINGS A FEW DEGREES WITH FORECAST HIGHS SIMILAR TO WEDNESDAY. STRONG DAYTIME HEATING WILL DESTABILIZE THE ATMOSPHERE DURING THE DAY AND COMBINED WITH A FAVORABLE JET AXIS/STRONG SHEAR PROFILE SUGGESTS STRONG TO SEVERE STORMS WILL BE POSSIBLE DURING THE LATE AFTERNOON AND EVENING HOURS. SPC CURRENTLY HAS THE AREA OUTLINED FOR THIS IN ITS DAY 4-8 OUTLOOK AND WILL CONTINUE TO MONITOR CLOSELY THIS TIME FRAME BY LATER SHIFTS. REST OF EXTENDED...COLD FRONT TO PUSH THROUGH THE AREA FRIDAY MORNING WITH CLEARING SKIES AND MORE COMFORTABLE CONDITIONS AS DEW POINTS DROP INTO THE LOWER 50S. DRY CONDITIONS AND SEASONABLE TEMPERATURES WILL END THE WORK WEEK WITH HIGHS IN THE UPPER 60S/LOW 70S AND LOWS IN THE UPPER 40S/LOWER 50S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1133 PM CDT SAT MAY 3 2014 VFR CONDITIONS WILL PERSIST THROUGH SUNDAY EVENING. A HIGH PRESSURE RIDGE WILL SHIFT FROM THE UPPER MIDWEST TO THE GREAT LAKES. NORTHWEST WINDS WILL TURN TO NORTHEAST AND EAST ON SUNDAY AT AROUND 10 KTS TO 15 KTS. PERIODS OF MID LEVEL CLOUDINESS WILL BE FOUND THROUGH THE TAF CYCLE... WITH POTENTIAL FOR SOME SPRINKLES AND A FEW HIGH BASED LIGHT SHOWERS ON SUNDAY AS WEAK DISTURBANCE RIPPLES DOWN ALONG MID LEVEL BAROCLINIC ZONE. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...05 SYNOPSIS...DLF SHORT TERM...DLF LONG TERM...GROSS AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1124 PM MDT SAT MAY 3 2014 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 206 PM MDT SAT MAY 3 2014 FRONT CURRENTLY DRAPE ACROSS THE FORECAST AREA. 70S ARE OVER THE NORTHEAST HALF WITH 80S OVER THE SOUTHWEST HALF. THIS BOUNDARY WILL MAKE FOR A DIFFICULT WIND AND TEMPERATURE FORECAST THROUGH TOMORROW. TEMPERATURES SHOULD STAY WARM WHERE THE WINDS STAY UP. SOME LOCATIONS ON BOTH SIDES WILL HAVE LIGHTER WINDS SO COULD SEE SOME LOCATIONS BEING ABLE TO DROP. AS TODAY...MODELS DIFFER ON THE POSITION OF WHERE THE FRONT IS DURING THE DAY. THE ECMWF IS FURTHER WEST WITH FRONT AND IS THE COOLEST. OF THE MODELS THAT GO OUT LONG ENOUGH...THE NAM IS CLOSER TO THE RAP AND HRRR WHICH ARE DOING WELL RIGHT NOW. MOST OF THE OUTPUT HOW MORE OF THE FORECAST ON THE WARM SIDE...AND WILL BE GOING THAT DIRECTION. AT THIS TIME THE NORTHEAST CORNER LOOKS TO BE THE COOLEST WITH SUMMER-LIKE TEMPERATURES EXPECTED OVER TO THE WEST OF THE FRONT. REFER TO THE CLIMATE SECTION BELOW. ALSO REFER TO THE FIRE SECTION BELOW FOR TOMORROWS FIRE WEATHER DISCUSSION. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 258 PM MDT SAT MAY 3 2014 MAIN CONCERNS WITH THE EXTENDED FORECAST ARE POSSIBLE FIRE WEATHER CONDITIONS AND PRECIPITATION ASSOCIATED WITH A PASSING LONGWAVE TROUGH. WARM AND DRY CONDITIONS ARE ANTICIPATED INTO THE BEGINNING OF NEXT WEEK. A SLOW COOLING TREND SHOULD BEGIN MONDAY WITH COOLING 850 MB TEMPERATURES AND A WEAK COLD FRONT LINGERING. MUCH HIGHER DEWPOINTS AND HUMIDITY SHOULD POOL ALONG AND BEHIND THE COLD FRONT...ALLOWING FOR A CHANCE OF FOG BOTH SUNDAY NIGHT AND MONDAY NIGHT. DURING THE DAYLIGHT HOURS...CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE SOUTH OF THE FRONT WHERE SOUTHWEST WINDS INCREASE AND VERY DRY AIR REMAINS. FUEL STATUS REMAINS THE MAIN ISSUE WITH GREEN-UP ONGOING ACROSS THE TRI-STATE AREA. A STRONG LONGWAVE TROUGH SWINGS ACROSS THE HIGH PLAINS DURING THE MIDDLE OF THE WEEK...BRINGING THE ONLY CHANCES FOR PRECIPITATION IN THE LONG TERM FORECAST. DUE TO DRY AIR REMAINING ACROSS PORTIONS OF THE TRI-STATE AREA...PRECIPITATION CHANCES WILL BE CONFINED TO LOCATIONS ALONG AND BEHIND THE FRONT WHERE AVAILABLE MOISTURE IS HIGHER. THE DRYLINE REMAINS WELL TO THE EAST DURING PERIODS OF BEST ATMOSPHERIC LIFT AND INSTABILITY SO BEST CHANCES FOR SEVERE WEATHER SHOULD BE CONFINED TO EASTERN KANSAS AND OKLAHOMA. WITH INCREASING SHEAR AND INSTABILITY...CAN NOT RULE OUT A FEW STRONG TO SEVERE STORMS BUT DO NOT THINK A WIDESPREAD OUTBREAK IS LIKELY AT THIS TIME. PRECIPITATION SHOULD BE SPORADIC SO NOT EVERYBODY WILL RECEIVE A NEEDED RAINFALL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1123 PM MDT SAT MAY 3 2014 VFR EXPECTED AT BOTH KGLD AND KMCK THROUGH THE TAF PERIOD. UPPER RIDGE WILL SUPPRESS ANY CHANCES FOR PRECIPITATION. A FRONTAL BOUNDARY STALLED OUT ACROSS THE AREA SEPARATES A HOT DRY AIR MASS TO THE WEST AND A WARM SLIGHTLY MORE MOIST AIR MASS TO THE EAST. KMCK WILL LIE NEAR OR JUST ON THE COOL SIDE OF THE FRONT SUNDAY MORNING. AS A RESULT...THERE IS A LOW PROBABILITY...LESS THAN 10 PERCENT...OF FOG FORMING AROUND SUNRISE. VISIBILITIES MAY BRIEFLY BE REDUCED TO MVFR IF IT WERE TO OCCUR...BUT CONFIDENCE IS LOW AND WILL NOT INCLUDE IN THE KMCK TAF ATTM. && .FIRE WEATHER... ISSUED AT 206 PM MDT SAT MAY 3 2014 LIKE TODAY...THE RELATIVE HUMIDITIES WILL DEFINITELY REACH CRITICAL FIRE WEATHER CONDITIONS. HOWEVER...THERE IS SOME UNCERTAINTY ON FUEL STATUS AND ON THE WINDS. WHAT DATA CAN BE FOUND WOULD INDICATE THAT WE ARE IN GREEN-UP BUT THAT MAY BE MOSTLY FOR GROWING CROPS. WINDS TO THE WEST OF THE FRONT COULD BE GUSTY AND REACH THE NEEDED CRITERIA. HOWEVER...THERE IS A DECENT SPREAD IN THE MODEL OUTPUT ON THE POSITION OF THE FRONT AND RESULTANT WIND SPEEDS. IF THE STRONGER NAM WINDS WORK OUT...THEN SOME LOCATION IN THE SOUTHWEST HALF OF THE AREA COULD REACH CRITICAL FIRE WEATHER CONDITIONS. AT THIS TIME...TOO MUCH UNCERTAINTY TO ISSUE A WATCH WITH THE OVERNIGHT SHIFT NEEDING TO TAKE ANOTHER LOOK AT THIS. && .CLIMATE... ISSUED AT 206 PM MDT SAT MAY 3 2014 MOST OF THE AREA WILL HAVE A CHANCE TO BREAK DAILY RECORDS FOR MAY 4. THE FOLLOWING ARE THE RECORDS FOR SUNDAY. GOODLAND.....91 IN 2012 MCCOOK.......94 IN 2012 BURLINGTON...92 IN 1963 HILL CITY....93 IN 2012 COLBY........92 IN 1924 TRIBUNE......94 IN 1952 YUMA.........89 IN 1962 && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...BULLER LONG TERM...RRH AVIATION...024 FIRE WEATHER...BULLER CLIMATE...BULLER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
333 AM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 AS ADVERTISED BY THE NAM...STRONG MIDLEVEL FRONTOGENESIS HAS SPAWNED AN AREA OF SHOWERS AND THUNDERSTORMS ACROSS SD THIS MORNING. THE RAP SHOWS THIS FORCING MECHANISM MOVING QUICKLY EAST AWAY FROM THE FCST AREA BY 12Z THIS MORNING AND THIS IS CONSISTENT WITH THE LATEST RADAR TRENDS. THE RAP AND NAM GENERATE A FEW HUNDRED JOULES OF ELEVATED INSTABILITY THIS AFTN ACROSS PINE RIDGE SUGGESTING THE POTENTIAL FOR ISOLATED TSTM DEVELOPMENT. THE FORECAST IS DRY AS NEITHER MODEL IS GENERATING AND QPF IN THAT AREA. THE TEMPERATURE FORECAST TODAY HAS HIGHS RANGING FROM THE 60S NORTH TO UPPER 80S IN THE FAR SOUTHWEST. THE CANADIAN HIGH PRESSURE SYSTEM WILL CONTINUE TO RIDGE THRU MUCH OF THE FCST AREA TODAY SUPPORTING THIS TEMPERATURE FORECAST WHICH IS CONSISTENT WITH THE 07Z RUN OF THE RAP. ALL MODELS EXCEPT THE GEM SUGGEST THE POTENTIAL FOR STRATUS DEVELOPMENT TONIGHT BUT THE NAM AND ECM ONLY SHOW 85 PERCENT RH IN THE 500M AGL LEVEL VS THE GFS AROUND 98 PERCENT. THE BEST APPROACH AT THIS TIME WOULD BE TO WAIT FOR LATER MODEL DATA. A SMALL PATCH OF STRATUS HAS WORKED INTO PINE RIDGE THIS MORNING WHICH SHOULD BURN OFF BY NOON TIME ACCORDING TO THE RAP MODEL. LOWS TONIGHT FALL INTO THE 40S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MONDAY BEGINS WITH A BROAD RIDGE ACROSS MOST OF THE CONUS...WITH A TROUGH DIGGING INTO THE PAC NW AND ONE OFF THE NEW ENGLAND COAST. AT THE SFC A LEE SIDE TROUGH MEANDERS ACROSS THE FRONT RANGE FROM A LOW IN S CENTRAL CANADA TO A LOW IN KANSAS. DURING THE AFTERNOON SUNNY SKIES WILL MIX MID AND UPPER TEENS 850 MB TEMPS AND HIGHS IN THE 70S AND LOWER 80S. OVERNIGHT AN UPPER LEVEL DISTURBANCE WILL RIDE THE RIDGE ACROSS THE DAKOTAS. THIS WILL COMBINE WITH A LL JET TO PRODUCE SOME SHOWERS AND A FEW THUNDERSTORMS. MAJORITY OF THE ACTIVITY TO THE NORTH...HOWEVER THE NAM AND THE GFS SUPPORT SOME BUILDING SOUTH WHERE THERE IS SLIGHTLY BETTER MOISTURE. THE MOISTURE IS ONLY SLIGHTLY BETTER AND HAVE CONCERNS THE ACTIVITY WILL NOT DEVELOP THIS FAR SOUTH...AWAY FROM THE MAIN DISTURBANCE. MILD LOWS EXPECTED IN THE UPPER 40S TO AROUND 50. TUESDAY THE UPPER LEVEL TROUGH DIGS TOWARDS THE DESERT SOUTHWEST WITH THE RIDGE TO AMPLIFY OVER THE MISS RVR VALLEY. THIS WILL BEGIN THE TRANSITION TO MORE SW FLOW OVER THE HIGH PLAINS. TUESDAY STILL LOOKS DRY...THEN ANOTHER DISTURBANCE TO PUSH ACROSS THE AREA TUESDAY EVENING. MODELS INITIATE ACTIVITY TO THE WEST...WHICH SHOULD THEN PUSH NE ACROSS THE AREA. DRY AIR WILL BE TOUGH TO OVERCOME...ESPECIALLY IN THE SW...SO POPS CONFINED TO THE NW ZONES TUESDAY NIGHT. BY WEDNESDAY AND THURSDAY THE UPPER LEVEL TROUGH WILL BE CROSSING THE CENTRAL ROCKIES WHILE A COLD FRONT DRIFTS IN FROM THE NW. MEANWHILE SFC LOW STRENGTHEN OVER E CENTRAL COLORADO. THE LOW WILL THEN LIFT NE ACROSS NEB. TIMING STILL OFF A LITTLE BETWEEN THE MODELS...AND THE SLOWER GFS AND GEM HAVE A MORE PRONOUNCED DRY SLOT INTO SW AND S CENTRAL NEB. ANOTHER CONCERN IS THURSDAY NIGHT AS THE SYSTEM PUSHES EAST. THE EC DRAWS DOWN SOME COOLER AIR INTO FAR NW NEB...COLD ENOUGH FOR POSSIBLY A MIX. CURRENT THOUGH IS THE TEMPS TO NOT FALL FAST ENOUGH INTO THE MID 30S FOR ANY MIX AT THIS POINT AND NO MENTION OF SNOW. THE CLOUDS AND COOLER AIR BEHIND THE FRONT WILL RESULT IN 60S AND 70S ON WED AND 50S AND 60S FOR THURS. BY FRIDAY THE SYSTEM IS EAST WITH SLIGHT RIDGING OVER THE WEST. 850 MB TEMPS SLOWLY REBOUND AND A WARM UP IS EXPECTED. AFTER 60S ON FRIDAY...MORE 70S ARE FORECAST FOR SATURDAY. A LOW WILL PUSH ACROSS THE DAKOTAS IN THE ZONAL TO NW WEST FLOW. MOISTURE IS LIMITED TO BASICALLY THE PACIFIC AND WILL KEEP FORECAST DRY FOR NOW. WILL MONITOR AS WE MAY NEED TO ADD SOME ISOLATED SPRINKLES OR LIGHT SHOWERS IN THE COMING DAYS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1220 AM CDT SUN MAY 4 2014 UNLIMITED CEILING AND VISIBILITY IS EXPECTED TONIGHT IN MOST OF CENTRAL AND WESTERN NEBRASKA. EAST WIND IN THE WEST MAY PRODUCE LOCALIZED FOG/MIST IN THE WEST SOUTH AND WEST OF IEN. WIND IN NORTHERN NEBRASKA IS EXPECTED TO BE 070-100 AT 10-14KT. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1140 PM CDT SAT MAY 3 2014 .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 330 PM CDT SAT MAY 3 2014 THE MAIN FORECAST CONCERNS THROUGH THE SHORT TERM WILL BE TEMPERATURES...THEN SMALL PRECIPITATION CHANCES TONIGHT AND EARLY SUNDAY...LATE SUNDAY NIGHT AND ALSO TUESDAY. THIS MORNING/S UPPER AIR MAPS SHOWED A CLOSED H5 LOW PRESSURE SYSTEM APPROACHING THE PACIFIC NORTHWEST WITH 100M+ HT FALLS. A NARROW RIDGE EXTENDED FROM WESTERN MONTANA TOWARD ARIZONA. CLOSED H5 LOW PRESSURE WAS ALSO CENTERED OVER MANITOBA WITH IT/S TROF STRETCHING SOUTHEAST INTO THE GREAT LAKES AND MID ATLANTIC STATES. THIS MID LEVEL TROF HAS RESULTED IN A PUSH OF THE SURFACE FRONT TO SOUTH OF MANHATTAN KS TOWARD EMPORIA AND SOUTH OF HAYS KS. THERE WAS NORTHWEST FLOW ALOFT OVER THE PLAINS AND A RIBBON OF MOISTURE WAS NOTED AT THE MID LEVELS AND ALSO AT H85 ACROSS WESTERN SD AND WESTERN NEBRASKA. MID LEVEL WARM AIR ADVECTION AND FRONTOGENESIS ALONG WITH STEEP LAPSE RATES RESULTED IN A SMALL AREA OF SHOWERS/SPRINKLES FROM SD INTO NEBRASKA AND WESTERN IOWA. THROUGH THE SHORT TERM...THERE WILL BE THESE SUBTLE FEATURES THAT WILL BRING SOME PRECIP CHANCES TO THE AREA...HOWEVER ANY WIDESPREAD PRECIPITATION LOOKS TO HOLD OFF UNTIL LATER IN THE WEEK. WARMER AIR WILL BE LIFTING NORTHWARD LATER THIS AFTERNOON AND TONIGHT WITH STRENGTHENING H85 WINDS AND SOME MOISTURE ALONG AND NORTH OF THE H85 WARM FRONT. MEANWHILE...FRONTOGENESIS INCREASES AS WELL NEAR THE SD/NEBRASKA BORDERS. SOME OF THE SHORT RANGE HIGH RES MODELS SHOW ECHOES ALOFT IN SOUTHEAST NEBRASKA AS EARLY AS LATE THIS AFTERNOON. THE RAP AND 4KM WRF HAVE PRECIP DEVELOPING IN NORTHEAST NEBRASKA AFTER 09Z...THE NAM BETWEEN 06Z- 09...AND THE GFS BETWEEN 06Z-12Z. ALTHOUGH THERE MAY BE SOME SPRINKLES OR ISOLATED SHOWERS FARTHER SOUTH...HOWEVER DUE TO LOW CONFIDENCE...HAVE ONLY MAINTAINED ISOLATED SHOWERS AND A POSSIBLE RUMBLE OF THUNDER FOR NORTHEAST NEBRASKA BETWEEN 06Z AND 12Z. SOME OF THESE SHOWERS MAY LINGER IN THE NORTHEAST SUNDAY MORNING. SUNDAY...THE SURFACE FRONT WILL STILL BE TO THE SOUTH OF THE FORECAST AREA WITH A BRISK EAST SURFACE FLOW. THIS SHOULD HOLD TEMPERATURES IN THE 60S...WITH 70S FOR SOUTHEAST NEBRASKA. TEMPERATURES NEAR THE KS BORDER WILL NEED TO BE MONITORED DUE TO THE FRONT NEARBY. THERE IS SOME WEAK LIFT...HOWEVER MOISTURE APPEARS LIMITED...THUS HAVE LEFT DRY. SUNDAY NIGHT...ANOTHER WEAK SHORTWAVE PASS THROUGH THE NORTHWEST FLOW ALOFT AND AGAIN...THERE MAY BE ISOLATED SHOWERS...HOWEVER THE COVERAGE IS TOO LOW TO MENTION AT THIS TIME. THE FLOW ALOFT TRANSITIONS TO SOUTHWEST FLOW AND A WEAK IMPULSE COULD BRING ISOLATED SHOWERS TUESDAY. WARM MID LEVEL TEMPERATURES ARE IN PLACE AND THE CURRENT FORECAST IS DRY...HOWEVER THIS WILL NEED TO BE WATCHED AS INSTABILITY INCREASES. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 PM CDT SAT MAY 3 2014 STILL SOME SIGNIFICANT MODEL DIFFERENCES FOR TEMPERATURES WED. TRENDED WITH THE EC THAT HAS THE HOTTER TEMPERATURES ACROSS THE SOUTHERN PART OF THE FORECAST ARE COMPARED TO THE COOLER GFS. SHOWER AND THUNDERSTORM CHANCES INCREASE FOR WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WITH MUCH DEEPER MOISTURE RETURNING TO THE REGION...A SURFACE FRONT IN THE AREA AND THE LONG WAVE TROF MOVING TO THE PLAINS. NUDGED RAIN CHANCES UP FOR THURSDAY/THURSDAY NIGHT.SHEAR AND INSTABILITY INCREASE...HOWEVER FRONTAL PLACEMENT FOR THURSDAY WILL BE A KEY FACTOR FOR SEVERE WEATHER POTENTIAL THURSDAY/THURSDAY NIGHT. SOME ENERGY MAY LAG AND MAY HAVE TO INCLUDE PRECIP CHANCES INTO FRIDAY...BUT FOR NOW FRI/SAT ARE DRY. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1140 PM CDT SAT MAY 3 2014 VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD WITH ANY CEILINGS ABOVE 9000 FEET. EAST WINDS WILL INCREASE TO OVER 10 KNOTS MID TO LATE MORNING SUNDAY WITH SOME GUSTS NEAR 20 KNOTS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...ZAPOTOCNY LONG TERM...ZAPOTOCNY AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
109 AM EDT SUN MAY 4 2014 .SYNOPSIS... HIGH PRESSURE WILL BRING PLEASANT EARLY MAY WEATHER ACROSS THE REGION THROUGH MONDAY. A WEAK COLD FRONT FROM THE NORTH WILL STALL OVER OR JUST NORTH OF THE AREA LATE MONDAY THROUGH WEDNESDAY. A BUILDING UPPER LEVEL RIDGE OF HIGH PRESSURE WILL BRING VERY WARM CONDITIONS LATE IN THE WEEK. THERE IS LITTLE CHANCE FOR RAIN THROUGH THE PERIOD. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 100 AM SUNDAY...A MODERATE NORTHWEST WIND IN THE 2500-10000 FOOT LAYER IS BEING PRODUCED BY HIGH PRESSURE OVER THE WESTERN GULF OF MEXICO. THIS LAYER IS BONE-DRY AND CLEAR SKIES SHOULD PERSIST THROUGH (AND BEYOND) DAYBREAK. WHILE MOST AREAS STILL HAVE 3-6 MPH WINDS THERE ARE TWO EXCEPTIONS: STRONGER WEST-SOUTHWEST WINDS ALONG THE BRUNSWICK COUNTY COAST HAVE GUSTED OVER 20 MPH AT OCEAN CREST PIER AND ON BALD HEAD ISLAND WITHIN THE PAST FEW HOURS. THIS MARINE EFFECT SHOULD WANE GRADUALLY OVER THE NEXT FEW HOURS AS SURFACE WINDS VEER MORE NORTHWESTERLY. ALSO...WINDS HAVE BECOME DEAD CALM AT THE LBT AIRPORT WITH TEMPERATURES PLUNGING INTO THE LOWER 50S AT 1 AM. UNLESS WINDS "RECOUPLE" HERE WE COULD SEE UPPER 40S BY MORNING! LOW TEMPERATURES SHOULD END UP IN THE LOWER TO MIDDLE 50S FOR MOST AREAS...WITH LOCAL VARIATIONS DEPENDING ON HOW MUCH WIND CONTINUES THROUGH DAYBREAK. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 230 PM SATURDAY...THE MID LEVEL TROUGH WILL SHARPEN EVER SO SLIGHTLY THROUGH THE PERIOD AS RIDGING BUILDS ACROSS THE CENTRAL PLAINS. AT THE SURFACE...A WEAK FRONT WILL MOVE SLOWLY ACROSS THE AREA FROM EARLY MONDAY UNTIL EARLY TUESDAY. THE 1200 UTC GFS IS A LITTLE DRIER WITH ANY ACTIVITY JUST TO THE NORTHEAST LATE IN THE PERIOD BUT I WILL HOLD ON TO THE SLIGHT CHANCE POPS AS THIS IS LIKELY WAIVER BACK AND FORTH. THIS LEAVES ESSENTIALLY A TEMPERATURE FORECAST AND RATHER WARM ONE AT THAT. WITH DOWNSLOPE FLOW PREVAILING FROM ABOUT 850MB AND ABOVE THE WARMER NAM/MET NUMBERS SHOULD WORK BETTER. THIS LEADS TO LOWER TO MIDDLE 80S SUNDAY AND EVEN WARMER MONDAY...POSSIBLY ECLIPSING 90 EXTREME SOUTHWEST AREAS. OVERNIGHT LOWS MODIFY FROM AROUND 60 MONDAY MORNING TO THE LOWER 60S TUESDAY. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 230 PM SATURDAY...TOUGH CALL ON WHERE BACK DOOR COLD FRONT WILL BE ON TUESDAY WITH MAIN IMPACTS WITH RESPECT TO TEMPS. ANYWHERE SOUTH OF THE BOUNDARY SHOULD GET QUITE WARM WHILE MORE SEASONABLE WEATHER EXPECTED TO ITS NORTH BOTH AS A FUNCTION OF A LITTLE CAA AND SOME ADDITIONAL CLOUDS COVER. PRECIP CHANCES APPEAR TO REMAIN CONFINED NEAR THE UPPER LEVEL FRONT WHICH WILL STAY NORTH OF THE AREA. TEMPS MAY TAKE A DIP BACK TO SEASONABLE AREA- WIDE ON WED AS THE BOUNDARY SAGS...BUT IT BOTH WEAKENS AND LIFTS BACK TO THE NORTH THEREAFTER. BUILDING UPPER RIDGE TO BRING A LATE WEEK RETURN OF UNSEASONABLE WARMTH. THE LOW LEVEL RIDGE REMAINS CLOSE ENOUGH TO THE COASTLINE TO KEEP THE BEST MOISTURE ADVECTION TO OUR WEST PRECLUDING ANY CONVECTION. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AS OF 06Z...VFR WILL PREVAIL THROUGH THIS TAF PERIOD. CANNOT RULE OUT BRIEF TEMPO MVFR VSBYS AT KLBT GIVEN THE CALM WINDS AND LOW DEW POINT DEPRESSION...BUT OTHERWISE DO NOT ANTICIPATE ANY FOG ISSUES THROUGH DAYBREAK. TODAY WILL BE SUNNY AS NORTHWEST WINDS AOB 10 KTS EARLY BECOME SOUTHWEST 10-12 KTS IN THE AFTERNOON. WE COULD SEE INCREASING CIRRUS AFTER 00Z MONDAY AS A COLD FRONT SAGS SOUTHWARD AND STALLS ACROSS THE MID-ATLANTIC. EXTENDED OUTLOOK...A COLD FRONT WILL STALL NORTH OF THE AREA EARLY THIS WEEK...BRINGING A SLIGHT CHANCE OF SHOWERS LATE MONDAY/EARLY TUESDAY. ISOLATED SHOWERS POSSIBLE WEDNESDAY AS WELL...ALONG WITH MVFR/IFR CIGS WEDNESDAY AND THURSDAY MORNING. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 100 AM SUNDAY...A WEST-SOUTHWEST JET OF STRONGER WINDS IS SHOWING UP ON MULTIPLE MESONET AND COASTAL OBSERVATIONS ALONG THE BRUNSWICK COUNTY COAST. WIND GUSTS AT BOTH OCEAN CREST PIER AND BALD HEAD ISLAND HAVE APPROACHED 20 KNOTS IN THE PAST COUPLE OF HOURS. THE LATEST SEVERAL HRRR MODEL RUNS SHOW THIS JET OF STRONGER WINDS QUITE WELL...AND THE 00Z HRRR MODEL WAS USED TO REDRAW WIND FORECASTS OVER THE NEXT 10 HOURS. BASED ON LOCAL BUOY WAVE OBSERVATIONS I HAVE INCREASED NEAR-TERM SEA HEIGHT FORECASTS BY HALF A FOOT EAST OF CAPE FEAR...WITH LESSER CHANGES BY DAYBREAK. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 230 PM SATURDAY...MANAGEABLE CONDITIONS FOR THE MARINE COMMUNITY THROUGH THE PERIOD. SUNDAY WILL FEATURE ESSENTIALLY LIGHT AND VARIABLE WINDS UNDER A WEAK PRESSURE PATTERN. LATE SUNDAY/EARLY MONDAY A BRIEF PERIOD OF BETTER DEFINED SOUTHWESTERLY WINDS WILL DEVELOP AHEAD OF A BACKDOOR FRONT. THIS FRONT WILL MOVE ACROSS LATER MONDAY MORNING WITH ABOUT 12 HOURS OF NORTHWEST WINDS DEVELOPING. FINALLY...WINDS WILL TURN BACK TO THE SOUTHWEST AND INCREASE TO 15-20 KNOTS VERY LATE IN THE PERIOD. SIGNIFICANT SEAS WILL MOSTLY HOVER IN A NARROW RANGE OF 2-3 FEET WITH THE LIGHT WINDS AND WIND SHIFT. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 230 PM SATURDAY...BACKDOOR COLD FRONT SINKING INTO THE REGION ON TUESDAY AND MAY VERY WELL END UP BISECTING THE FORECAST ZONES NORTH TO SOUTH. A N TO NE WIND WILL OVERSPREAD ANY REGIONS THAT EXPERIENCE FROPA WHILE SRN ZONES LIKELY KEEP A LIGHT SWRLY FLOW. WIND AND SEAS BOTH MINIMAL DUE TO THE PRESENCE OF THE BOUNDARY AND NO REAL SWELL COMPONENT. THE FRONT WILL SAG A BIT FURTHER TO THE SOUTH ON WEDNESDAY AND MOST IF NOT ALL ZONES SHOULD SEE THE POST FRONTAL NRLY WIND COMPONENT AND POSSIBLY AN INCREASE IN SPEED OF JUST A FEW KT. WAVE FACES MAY STEEPEN SLIGHTLY BUT PREDOMINANT PD PROBABLY DOESN`T CHANGE. WEAKENING FRONT LIFTS BACK TO THE NORTH LATE WED NIGHT INTO THURSDAY ALLOWING FOR A RETURN OF LIGHT SWLY FLOW. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...SHK/TRA NEAR TERM...TRA SHORT TERM...SHK LONG TERM...MBB AVIATION...BJR/TRA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
409 AM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OFF THE WASHINGTON COAST WITH ADDITIONAL SHORTWAVES FARTHER UPSTREAM YET TO ROUND THE BASE OF THE TROUGH. A COUPLE OF SHORTWAVES WILL PEEL OFF THE MAIN UPPER LOW/TROUGH AND EJECT INTO NORTH DAKOTA THROUGH THE SHORT TERM PERIOD. FOR THE NEAR TERM/EARLY THIS MORNING...MONITORING THE NARROW BANDS OF PRECIPITATION ON THE BOWMAN AND BISMARCK RADARS. NOTHING SIGNIFICANT ON AMOUNTS VIA SURFACE REPORTS OR WEB CAMS...BUT AMOUNTS MAY BE FALLING IN BETWEEN ABOVE MENTIONED DATA POINTS. LATEST HRRR AND RAP BOTH LIFT THE NARROW BAND OF PRECIPITATION WEAKLY TO THE NORTHEAST THROUGH THE MORNING. THE ECMWF KEEPS THE BRUNT OF THE PRECIPITATION AMOUNTS IN THE FAR SOUTH...WHILE THE NAM/GFS SHOW A NARROW SWATH OF DECENT QPF WEST INTO SOUTH CENTRAL. WILL CONTINUE WITH A CHANCE TO LIKELY POPS MENTIONING SNOW/RAIN THROUGH MID MORNING BEFORE TRENDING DOWNWARD. LATER TODAY...CONSENSUS IS FOR THE NEXT SHORTWAVE TO MOVE FROM THE CENTRAL IDAHO PANHANDLE INTO NORTHERN NORTH DAKOTA BETWEEN 18Z SUNDAY AND 06Z MONDAY. THIS WILL RESULT IN CATEGORICAL POPS FOR THE NORTH DURING THIS TIME AND A CHANCE OF SHOWERS ELSEWHERE. TOWARD 00Z MONDAY...WEAK INSTABILITY PUSHES CLOSE TO OUR SOUTHWEST BORDER AND HAVE MAINTAINED A SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH AT LEAST MID WEEK. MEDIUM RANGE MODELS ARE STARTING TO COAL ESE AROUND A SIMILAR PROGRESSION OF A LARGE WESTERN CONUS TROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE MONDAY NIGHT...WITH PERIODS OF SHOWERS AND ISOLATED CONVECTION CONTINUING THROUGH WEDNESDAY NIGHT BEFORE TAPERING OFF THURSDAY. CONSENSUS QPF AMONGST THE GFS/ECMWF/GEM NOW SUPPORTS WIDESPREAD TOTAL RAINFALL OF 0.33 TO 1 INCH...LESS BULLISH THAN PREVIOUS DAYS. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. ANOTHER STORM SYSTEM COULD BRING ADDITIONAL SHOWERS TO THE FORECAST AREA ON SATURDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1206 AM CDT SUN MAY 4 2014 RAIN WILL MIX WITH AND CHANGE TO SNOW AT KISN/KDIK/KBIS OVERNIGHT AND CONTINUE THROUGH 17Z SUNDAY. EXPECT MVFR CIGS AT KISN/KDIK/KBIS...WITH CIGS LIFTING TO LOW VFR AT KBIS BY 17Z...WHILE KDIK/KISN WILL MAINTAIN MVFR CIGS INTO THE MID AFTERNOON HOURS SUNDAY. KJMS WILL CONTINUE WITH VFR CIGS THROUGH THE TAF PERIOD. ANOTHER ROUND OF PRECIPITATION IS EXPECTED SUNDAY EVENING RESULTING IN MVFR CIGS AND -RA AT KMOT/KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KS LONG TERM...RP KINNEY AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1206 AM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 1206 AM CDT SUN MAY 4 2014 LATEST BOWMAN RADAR SHOWS FRONTOGENESIS INITIATING AS NARROW INTENSIFYING BANDS OF PRECIPITATION HAVE DEVELOPED OVER SLOPE AND HETTINGER COUNTIES. BEST MODEL GUIDANCE ON THIS DEVELOPMENT IS A BLEND OF THE NAM/GFS...AS THE HIGHER RESOLUTION HRRR/RAP MODELS MISSING CURRENT PRECIPITATION AREA. INCREASED POPS FROM LIKELY TO CATEGORICAL WHERE PRECIPITATION BANDING HAS DEVELOPED. WILL MONITOR FOR SNOW ACCUMULATIONS OVERNIGHT...AS RAIN WILL INITIALLY BE THE PRIMARY FORM OF PRECIPITATION BUT WITH DYNAMIC COOLING BECOMING DOMINATE...EXPECT A CHANGEOVER TO SNOW IN THE NEXT FEW HOURS. UPDATE ISSUED AT 1003 PM CDT SAT MAY 3 2014 LATEST MESOSCALE MODELS ARE NOT DOING A GREAT JOB WITH PRECIPITATION OVER NORTHEAST MONTANA THIS EVENING. THE 4 MAY 00 UTC NAM MAY HAVE BEST INITIALIZED THIS SHOWER ACTIVITY. THERE ARE ALSO STILL SOME SHOWERS LOCATED OVER SOUTHEAST MONTANA INTO SOUTHWEST NORTH DAKOTA. LATEST SATELLITE IMAGERY INDICATES SHORTWAVE RIDGE OVER CENTRAL MONTANA BEING FLATTENED WITH SHORTWAVE ENERGY. ALTHOUGH INDIVIDUAL IMPULSES ARE HARD TO DISCERN OVER MONTANA...A STRONGER IMPULSE CAN BE SEEN MOVING ACROSS OREGON. THE AFOREMENTIONED NAM INDICATES A NARROW BAND OF PRECIPITATION TRACKING FROM EASTERN MONTANA THIS EVENING TOWARD THE BISMARCK AREA AROUND 12 UTC SUNDAY. GLOBAL MODELS AND TO A CERTAIN EXTENT...LATEST HRRR/RAP ARE STILL INDICATING THE SOUTHWEST AS THE MORE FAVORED AREA FOR PRECIPITATION OVERNIGHT BEFORE A BETTER CHANCE MOVES INTO THE WEST SUNDAY LATE MORNING OR AFTERNOON. FOR THE EVENING UPDATE...DID GIVE THE NAM SOME CREDIT AND EXTENDED POPS A BIT FARTHER NORTH THAN PREVIOUSLY FORECAST. THIS BROUGHT SOME CHANCE POPS FARTHER NORTH FROM AROUND WATFORD CITY TO THE BISMARCK AREA...BUT STILL LEFT THE HIGHEST POPS ACROSS THE SOUTHWEST FOR NOW. HOPEFULLY WHEN THE 00 UTC GLOBAL MODELS COME IN THERE IS A BETTER CONSENSUS. UPDATE ISSUED AT 649 PM CDT SAT MAY 3 2014 LATEST RADAR IMAGERY CONTINUES TO INDICATED ISOLATED SHOWERS CLIPPING SOUTHWEST NORTH DAKOTA WITH A DIMINISHING STRATOCUMULUS DECK ELSEWHERE. UPDATED POP AND SKY GRIDS BASED ON LATEST RADAR AND SATELLITE IMAGERY AND 22 UTC RAP MESOSCALE OUTPUT. KEPT A SLIGHT CHANCE OF SHOWERS EARLY THIS EVENING OVER THE SOUTHWEST AND DECREASED CLOUDS NORTH WEST AND CENTRAL. BROUGHT SOME HIGHER POPS INTO THE SOUTHWEST LATER THIS EVENING BUT BACKED THIS DOWN A BIT FROM THE PREVIOUS FORECAST BASED ON AFOREMENTIONED RAP GUIDANCE. PRECIPITATION CHANCES THEN INCREASE AFTER MIDNIGHT WITH INCREASING CLOUDS FROM WEST TO EAST. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 THE MAIN CONCERN IN THE SHORT TERM FORECAST PERIOD WILL BE THE CHANCE OF PRECIPITATION TONIGHT AND SUNDAY. THE SHORT TERM MODELS GENERALLY AGREE A FRONTOGENETIC PRECIPITATION BAND WILL DEVELOP LATER TONIGHT ACROSS PARTS OF WESTERN INTO SOUTH CENTRAL NORTH DAKOTA. THERE ARE STILL DIFFERENCES REGARDING HOW MUCH PRECIPITATION WILL ACCUMULATE IN THE BAND...WITH THE GFS MORE AGGRESSIVE THAN MOST SOLUTIONS. WILL USE A BLEND WHICH FAVORS WPC AMOUNTS FOR TONIGHT INTO SUNDAY. THIS WILL BRING NEAR A QUARTER OF AN INCH OF PRECIPITATION ACROSS PARTS OF SOUTHWEST NORTH DAKOTA TONIGHT. FORECAST SOUNDINGS SUGGEST THE RAIN COULD MIX WITH OR CHANGE TO SNOW IN SOME AREAS...AND NAM BUFR SOUNDINGS SHOW AROUND HALF AN INCH OF SNOW POSSIBLE AT KDIK. HAVE INCREASED SNOW AMOUNTS JUST SLIGHTLY IN THE GRIDS IN THE HEART OF THE FRONTOGENETIC BAND...BUT STILL KEPT AMOUNTS LESS THAN AN INCH AND MAINLY EXPECT THOSE ON GRASSY TYPE SURFACES. LATER SHIFTS WILL HAVE TO MONITOR TRENDS SINCE SNOW ACCUMULATIONS WITH FRONTOGENETIC FORCING CAN BE TRICKY. THE INITIAL BAND OF PRECIPITATION SHOULD DIMINISH SUNDAY MORNING...BUT ANOTHER SHORTWAVE APPROACHES THE NORTHERN PLAINS ALREADY SUNDAY AFTERNOON. WILL INCREASE POPS ACROSS THE WEST WITH THE HIGHEST CHANCES NEAR THE MONTANA BORDER. DECIDED TO PULL MENTION OF THUNDER FOR SUNDAY AFTERNOON WITH THE LATEST SHORT TERM MODELS KEEPING THE MUCAPE AXIS WEST AND SOUTH OF NORTH DAKOTA THROUGH SUNDAY AFTERNOON. THE MODELS ALSO DO NOT SHOW ANY CONVECTIVE PRECIPITATION THROUGH 00Z MONDAY...BUT THAT CHANGES SUNDAY NIGHT. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 341 PM CDT SAT MAY 3 2014 FORECAST HIGHLIGHTS IN THE LONG TERM PERIOD INCLUDE A CONTINUATION OF ACTIVE WEATHER THROUGH AT LEAST THURSDAY. THE PERIOD BEGINS WITH ZONAL WEST-TO-EAST FLOW ALOFT...THEN TRANSITIONS TO SOUTHWESTERLY FLOW ALOFT AS A LARGE-SCALE LONGWAVE TROUGH DEVELOPS AND DEEPENS OVER THE ROCKIES. THE ROCKIES TROUGH EVENTUALLY BEGINS MOVING OUT INTO THE PLAINS THURSDAY NIGHT...WITH MOST OF THE ENERGY IMPULSES FOR ENHANCED PRECIPITATION TO THE EAST OF THE FORECAST AREA. SUNDAY AFTERNOON AND NIGHT...THE FIRST IN A SERIES OF UPPER LEVEL SHORTWAVE ENERGY IMPULSES MOVES INTO THE STATE. KEPT A SLIGHT CHANCE OF THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. ON MONDAY...A SURFACE WARM FRONT ENTERS WESTERN NORTH DAKOTA AND REACHES THE CENTRAL PART OF THE STATE BY MONDAY EVENING. THIS WILL FOCUS THE LOW LEVEL CONVERGENCE AND PROVIDE GOOD INITIATION OF SHOWERS AND ENOUGH INSTABILITY FOR THUNDERSTORMS ACROSS MUCH OF WESTERN AND CENTRAL NORTH DAKOTA. MONDAY NIGHT AND TUESDAY A MORE SIGNIFICANT UPPER LEVEL SHORTWAVE MOVES ACROSS THE STATE. THIS WILL RESULT IN INCREASED CHANCES OF SHOWERS AND THUNDERSTORMS FOR THE FORECAST AREA. AT THIS TIME IT APPEARS THAT THE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT PERIOD SHOULD SEE THE CHANCE OF THUNDERSTORMS RESTRICTED TO SOUTHERN AND SOUTHEASTERN COUNTIES...BUT THE GOOD CHANCES OF SHOWERS REMAIN WITH THE INSTABILITY AND ENERGY IMPULSES IN THE SOUTHWEST FLOW ALOFT. RAINFALL AMOUNTS THROUGH THIS VERY ACTIVE PERIOD SUNDAY NIGHT THROUGH THURSDAY - SUPPORTED BY A CONSENSUS OF MODELS - RANGE FROM 0.5 INCHES TO AROUND 1.5 INCHES. SOME LOCALIZED AREAS MAY RECEIVE 2 INCHES - ESPECIALLY IN THUNDERSTORMS. RENEWED RISES ON AREAS RIVERS ARE LIKELY...BUT THERE IS STILL CONSIDERABLE UNCERTAINTY AS TO WHICH BASINS WILL RECEIVE THE BRUNT OF THE RAIN...AND THE SEVERITY OF THE IMPACTS. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1206 AM CDT SUN MAY 4 2014 RAIN WILL MIX WITH AND CHANGE TO SNOW AT KISN/KDIK/KBIS OVERNIGHT AND CONTINUE THROUGH 17Z SUNDAY. EXPECT MVFR CIGS AT KISN/KDIK/KBIS...WITH CIGS LIFTING TO LOW VFR AT KBIS BY 17Z...WHILE KDIK/KISN WILL MAINTAIN MVFR CIGS INTO THE MID AFTERNOON HOURS SUNDAY. KJMS WILL CONTINUE WITH VFR CIGS THROUGH THE TAF PERIOD. ANOTHER ROUND OF PRECIPITATION IS EXPECTED SUNDAY EVENING RESULTING IN MVFR CIGS AND -RA AT KMOT/KISN. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...CK LONG TERM...JV AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
425 AM EDT SUN MAY 4 2014 .SYNOPSIS... A WEAK TROF WILL MOVE ACROSS THE AREA TODAY. HIGH PRESSURE WILL BUILD SOUTHEAST INTO THE REGION TONIGHT AND WILL REMAIN NEARLY STATIONARY OVER THE LAKES THROUGH TUESDAY AND BEGIN TO MOVE EAST OF THE REGION TUESDAY NIGHT. A WARM FRONT WILL LIFT NORTH ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... NOT A CLEAR CUT FORECAST FOR TODAY...ESPECIALLY OVER THE EASTERN PORTION OF THE FORECAST AREA. SOME LIGHT SHOWERS ARE STILL MOVING ACROSS THE AREA...THEY ARE ASSOCIATED WITH AN UPPER JET THAT IS STILL ACROSS THE AREA AND A WEAK SURFACE TROF THAT WILL MOVE THROUGH THIS MORNING. LATE THIS MORNING AND AFTERNOON IS TOUGH. AN UPPER LOW OVER THE NORTHERN LAKES EARLY THIS MORNING WILL MOVE TOWARD WESTERN NEW YORK STATE FOR THE AFTERNOON...SO WENT WITH LIKELY POPS FOR NW PA. THE QUESTION IS HOW FAR WEST AND SOUTH SHOULD THE CHANCE BE. PLENTY OF DRY AIR WILL BE MOVING IN...SO TRIED TO LIMIT THE SHOWERS TO NE OH. THE HRRR MODEL HAS SOME SHOWERS NEAR THE SOUTHERN PORTION OF THE FORECAST AREA THIS AFTERNOON AND THIS IS ASSOCIATED WITH THE FRONT THAT MOVED ACROSS THE AREA SATURDAY NIGHT AND WAS NEAR THE OHIO RIVER THIS MORNING. WITH COLDER AIR ALOFT AND SOME CLOUDS WENT COOLER THAN YESTERDAY. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... THE FORECAST IS STILL NOT CLEAR CUT. TONIGHT WILL BE DRY WITH LIGHT WINDS AND MOSTLY CLEAR SKIES TO START AS HIGH PRESSURE WILL BE OVER THE AREA. THE CLOUDS WILL BE ON THE INCREASE DURING THE OVERNIGHT AND THE QUESTION IS HOW FAR EAST WILL THEY GET AND THE IMPACT ON FROST AND FREEZE. AT THIS TIME WITH CONFIDENCE LOW WILL ONLY MENTION PATCHY FROST FOR EXTREME NE OH AND NW PA. THE NEXT SHIFT WILL HAVE TO WATCH THE SKY COVER. IF CLOUDS DON`T COME IN...SOME LOCATIONS MAY HAVE TEMPERATURES BELOW FREEZING...WHILE IF THIN CLOUDS COME IN THEY MAY LIMIT THE PROBLEM TO SOME FROST. WILL MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK. FOR MONDAY A CHANCE OF SHOWERS AS A SHORT WAVE MOVES THROUGH EVEN WITH HIGH PRESSURE AT THE SURFACE OVER NE OH AND NW PA. DRY MONDAY NIGHT THROUGH TUESDAY NIGHT AND THEN A CHANCE WEDNESDAY INTO WEDNESDAY NIGHT AS A WARM FRONT MOVES ACROSS THE AREA. LOWEST CONFIDENCE IS IN THE FORECAST FOR MONDAY BECAUSE OF HIGH PRESSURE AT THE SURFACE BUT A FAIR AMOUNT OF OMEGA. A WARM TREND STARTING MID WEEK. WITH SOME QUESTIONS ABOUT THE CHANCES OF RAIN...THIS COULD CAUSE PROBLEMS WITH THE TEMPERATURE FORECAST...USED A BLEND OF GUIDANCE. && .LONG TERM /THURSDAY THROUGH SATURDAY/... MODELS INDICATE THE WARM FRONT WILL BE NORTH OF THE AREA ON THURSDAY WITH BREEZY SOUTHWEST WINDS PUSHING TEMPERATURES TO NEAR 80 DEGREES. REMOVED CHANCES OF PRECIPITATION FROM THE FORECAST WITH THE RIDGE AXIS OVERHEAD AND A CAP IN PLACE. MODELS SHOW SOME MOISTURE NEAR 850MB SO KEPT THE FORECAST AS PARTLY SUNNY...BUT WONT BE SURPRISED IF WE REALLY END UP BEING MOSTLY SUNNY. LOW PRESSURE WILL TRACK FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST ON THURSDAY NIGHT. MOISTURE ADVECTION DOES NOT REALLY RAMP UP UNTIL FRIDAY SO ONLY INCLUDED A LOW CHANCE POP IN A FEW OF THE WESTERN COUNTIES ON THURSDAY NIGHT. MOISTURE WILL OVERSPREAD THE AREA IN ADVANCE OF THE FRONT ON FRIDAY/FRIDAY NIGHT AND RAISED POPS TO NEAR 50 PERCENT. CHANCES OF PRECIPITATION ON SATURDAY WILL DEPEND ON WHERE THE FRONT STALLS AND IF IT PUSHES SOUTH OF THE FORECAST AREA. ENOUGH UNCERTAINTY TO CONTINUE WITH A CHANCE OF SHOWERS/THUNDERSTORMS AT THIS POINT WITH BEST CHANCES ACROSS THE SOUTHERN COUNTIES. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... RADAR IMAGERY SHOWING SCATTERED LIGHT SHOWERS MOVING EAST ACROSS THE AREA EARLY THIS MORNING. CONDITIONS WILL GENERALLY BE VFR BUT VISIBILITIES COULD BRIEFLY DROP TO 5SM OR SO IN SOME OF THE MODERATE SHOWERS WITH BEST CHANCES AT CAK/YNG. LIGHT SOUTHWEST WINDS WILL BECOME GUSTY AS THEY SHIFT TO WEST NORTHWEST BETWEEN 14-16Z ON SUNDAY MORNING. ANOTHER PUSH OF MOISTURE WILL MOVE SE OUT OF CANADA TOWARDS ERI...POSSIBLY EXTENDING AS FAR WEST AS YNG...WITH LIGHT SHOWERS POSSIBLE AGAIN EARLY THIS AFTERNOON. WINDS ARE EXPECTED TO DROP OFF TOWARDS 00Z AND BECOME LIGHT AND VARIABLE MOST LOCATIONS OVERNIGHT. .OUTLOOK...NON VFR MAY OCCUR WEDNESDAY NIGHT AS A WARM FRONT LIFTS ACROSS THE REGION WITH SHOWERS. && .MARINE... WEST TO SOUTHWEST WINDS WILL START THE DAY ON LAKE ERIE. WINDS ARE LIGHT ON THE WEST HALF OF THE LAKE BUT HOLDING IN THE 10-20 KNOT RANGE ON THE EAST HALF OF THE LAKE. A COLD FRONT WILL PUSH SOUTH ACROSS THE LAKE TODAY BUT APPEARS WEAKER THAN PREVIOUSLY THOUGHT. WINDS WILL VEER TO WEST NORTHWEST WITH THE PASSAGE OF THE FRONT EARLY THIS AFTERNOON. WAVES WILL INCREASE AS THE FLOW BECOMES MORE ONSHORE ON THE EAST HALF OF THE LAKE...INCREASING TO 2 TO 5 FEET FOR A WINDOW LATE THIS AFTERNOON. WE ALREADY HAVE A SMALL CRAFT ADVISORY IN EFFECT. CONDITIONS MAY END UP BEING MARGINAL FOR THE SMALL CRAFT ADVISORY AND WE MAY BE ABLE TO CANCEL IT EARLY IF MODELS CONTINUE TO TREND LIGHTER WITH THE WINDS. CONDITIONS WILL IMPROVE QUICKLY TONIGHT AS HIGH PRESSURE BUILDS IN FROM THE WEST. WINDS WILL HAVE A EAST TO NORTHEAST DIRECTION THROUGH WEDNESDAY AS HIGH PRESSURE PASSES NORTH OF THE LAKE. A WARM FRONT WILL LIFT NORTH ACROSS THE LAKE ON WEDNESDAY NIGHT WITH A WARM AND STABLE SOUTHERLY FLOW EXPECTED BY THURSDAY. ACTIVE WEATHER TO FINISH THE WEEK WITH PERIODS OF SHOWERS AND THUNDERSTORMS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ146>149. && $$ SYNOPSIS...KIELTYKA NEAR TERM...KIELTYKA SHORT TERM...KIELTYKA LONG TERM...KEC AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
354 AM CDT SUN MAY 4 2014 .SHORT TERM...TODAY THROUGH TUESDAY CURRENT RADAR IMAGERY SHOWING SCT SHOWERS AND EVEN A FEW THUNDERSHOWERS ACROSS CENTRAL SD AS MID LEVEL IMPULSE MOVES THROUGH. FURTHER EAST IN THE COLDER AIR...A MIX OF RAIN/SLEET/SNOW WAS OBSERVED AT ABR. HAVE ADJUSTED POP/WX GRIDS ACCORDINGLY AND WILL LIKELY NEED ADDITIONAL UPDATES IN A COUPLE HOURS. THE PAST SEVERAL RUNS OF THE HRRR AND THE 00Z EC HANDLED THIS SITUATION THE BEST...WITH THE 00Z GFS AND NAM WAY TOO FAR NORTH WITH THE PRECIPITATION. EXPECT THIS ACTIVITY TO CONTINUE SLIDING EAST THROUGH THE MORNING...MAINLY AFFECTING AREAS EAST OF THE MISSOURI RIVER. WITH COOL EASTERLY SFC FLOW DEVELOPING ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES...WILL BE A COOL DAY TODAY WITH HIGHS ONLY IN THE LOW TO MID 50S FOR MOST AREAS. WILL SEE ANOTHER WAVE OF ENERGY TACK EAST ACROSS THE AREA OVERNIGHT...AND A SLIGHTLY STRONGER ONE MONDAY NIGHT INTO TUESDAY. ALTHOUGH THE LATTER SYSTEM LOOKS TO BRING BEST PRECIP CHANCES TO THE WESTERN CWA AT THIS TIME. AS FAR AS INSTABILITY GOES...IT APPEARS WESTERN AND CENTRAL SD STAND THE BEST CHANCE TO SEE ANY CONVECTION WITH THESE COMING WAVES OF ENERGY. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY AN AREA OF LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS AT THE START OF THE PERIOD. THIS SYSTEM COMBINED WITH UPPER LEVEL SOUTHWEST FLOW WILL BRING INSTABILITY AND TSTORM CHANCES TO THE NORTHERN PLAINS THROUGH WED NIGHT. AN UPPER LOW WILL THEN TRANSITION OVER SD/NE BRINGING CONTINUED STORM CHANCES THURSDAY. BY FRIDAY SFC HIGH PRESSURE WILL BRIEFLY BUILD IN TO THE PLAINS BRINGING DRIER WEATHER. THEN A TROUGH MOVES THROUGH ON SAT EVEN AS ANOTHER LONG WAVE TROF TO THE WEST BEGINS TO EJECT UPPER LEVEL ENERGY INTO THE DAKOTAS. THIS MEANS TSTORMS WILL BE BACK IN THE FORECAST FOR THE WEEKEND. TEMPERATURES WILL BE NEAR OR BELOW NORMAL THROUGH THE PERIOD DUE TO RAIN AND CLOUD COVER. GOOD MIXING ON MOST DAYS EXCEPT FRIDAY WILL PUSH HIGHS INTO THE 60S. && .AVIATION... 06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS EXPECT VFR CEILINGS THROUGH THE NIGHT AND SUNDAY AT ALL LOCATIONS. ALSO...EXPECT SOME LIGHT RAIN SHOWERS WITH A SHORT WAVE TROUGH MOVING IN FROM THE NORTHWEST LATER TONIGHT AND SUNDAY MORNING. THESE COULD AFFECT MBG...ABR AND ATY AND STAY NORTH OF PIR. DONT EXPECT ANY BIG REDUCTION IN VISIBILITY. THE WINDS COULD GET A LITTLE BREEZY ON SUNDAY OUT OF THE SOUTHEAST AT 15 TO 25 KNOTS. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...TMT LONG TERM...WISE AVIATION...WISE WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
508 AM EDT SUN MAY 4 2014 .SYNOPSIS... A FRONT WILL BECOME STATIONARY FROM VIRGINIA TO THE MID MISSISSIPPI VALLEY BY LATE TODAY. THIS BOUNDARY WILL REMAIN IN THE AREA THROUGH WEDNESDAY...THEN LIFT NORTH INTO NEW ENGLAND. THURSDAY AND FRIDAY HIGH PRESSURE ALOFT AND UNSEASONABLY WARM AIR BUILD OVER THE MID ATLANTIC REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 400 AM EDT SUNDAY... CLOSED UPPER LOW OVER THE GREAT LAKES MOVES ACROSS NEW ENGLAND BY THIS AFTERNOON. THIS KEEPS THE FORECAST AREA IN DEEP NORTHWEST FLOW THROUGH TONIGHT. WEAK STATIONARY FRONT WITH AXIS OF DEEPER MOISTURE SETS UP FROM SOUTHERN INDIANA TO CENTRAL VIRGINIA TODAY. MODELS STILL DIFFER IN EXACT ALIGNMENT OF WHERE PRECIPITATION MAY ENTER THE COUNTY WARNING AREA LATE THIS AFTERNOON. BETTER INSTABILITY REMAINS JUST WEST OF THE FORECAST AREA THROUGH MID AFTERNOON. THUNDERSTORMS THAT DEVELOP TO THE WEST WILL TRACK INTO THE AREA LATE TODAY. RAP GUIDANCE HAS PRECIPITATION AFTER 2PM AS FAR NORTHERN AS GREENBRIER COUNTY...WHILE THE NAM AND GFS WERE POINTING MORE TOWARD TAZEWELL AND SMYTH COUNTIES. PLENTY OF SUNSHINE THIS MORNING TO PRODUCE DEEP MIXING. WINDS WILL BE GUSTING OUT OF THE NORTHWEST SO COVERAGE OF ANY SHOWERS OR THUNDERSTORMS THAT GET ACROSS THE BLUE RIDGE WILL BE LIMITED. BUFKIT SUPPORTED WIND GUSTS OF 30 TO 40 MPH ABOVE 3000 FEET THIS AFTERNOON AND EARLY EVENING WITH WIND SPEEDS DROPPING OFF QUICKLY WITH THE LOSS OF HEATING. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM EDT SUNDAY... AN UPPER TROUGH BUILDING ALONG THE WEST COAST WILL EVENTUALLY CARVE A CLOSED UPPER LOW OVER SOUTHERN CALIFORNIA BY TUESDAY. IN RESPONSE...HEIGHTS WILL BUILD THROUGH THE MISSISSIPPI RIVER VALLEY AND GREAT LAKES. CONFLUENCE OVER NEW ENGLAND WILL PRODUCE A SURFACE HIGH WHICH WILL WEDGE INTO VIRGINIA...PERHAPS SENDING SLIGHTLY COOLER AND DRIER AIR INTO SW VA. THE STRENGTH AND POSITION OF THIS DIFFUSE BOUNDARY WILL DETERMINE CHANCES FOR PRECIP TUESDAY AND WEDNESDAY. MONDAY HOLDS THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS...MAINLY RT 460 AND POINTS NORTH. ALTHOUGH SOME SREF MEMBERS ARE SENDING PRECIP SOUTH OF THIS LINE...THE OP GFS SEEMS TO CONTAIN CONVECTIVE FEEDBACK WITH A SPURIOUS VORT MAX OVER WESTERN NORTH CAROLINA AT 0Z TUES. HOWEVER...CAN`T TOTALLY RULE OUT SHOWERS AND A FEW STORMS NEAR THE NC/VA BORDER MONDAY. INSTABILITY DEFINITELY EXISTS ON MONDAY...AND OF COURSE WITH THE POSITION OF THE STATIONARY BOUNDARY...GOOD LLVL SHEAR IS ALSO A FACTOR. THE MISSING INGREDIENT IN THE STEW IS FORCING...AS THERE DOESN`T SEEM TO BE MUCH OF A TRIGGER FOR SURFACE PARCELS. PERHAPS A CLEARER SKY AND MORE SUNSHINE MONDAY MORNING WILL PROVIDE THAT EXTRA NUDGE NECESSARY. COULD BE AN ISOLATED STRONG STORM RT 460 AND NORTH MONDAY. SOME EASTERLY COMPONENT AND THE POSITION OF THE BOUNDARY OVER SW VA COULD KEEP LYH/ROA COOLER THAN BLF/JFZ/MKJ CORRIDOR BOTH TUESDAY AND WEDNESDAY. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 345 PM EDT SATURDAY... PROGRESSIVE PATTERN WILL BECOME MORE AMPLIFIED DURING THE PERIOD AS DEEP UPPER TROUGH DEVELOPS IN THE WESTERN U.S. AND TROUGHING DEEPENS OVER THE NORTHERN ATLANTIC. THIS WILL RESULT IN AN AMPLIFYING MID-LEVEL RIDGE THROUGH THE OH/TN VALLEY. THE LONG STANDING BAROCLINIC ZONE OF THE FIRST HALF OF THE WEEK WILL BEGIN TO LIFT NORTH OF THE REGION WEDNESDAY...BUT MODELS NOW INDICATING THAT IT WILL BE AT LEAST ONE DAY SLOWER TO EXIST TO THE NORTHEAST THAN EARLIER INDICATED. THUS...THERE REMAINS THE POTENTIAL FOR SHRA/TSRA TO AGAIN DEVELOP WED AFTERNOON. BY THIS TIME...THE BEST SUPPORT WILL BE ACROSS THE ALLEGHANY HIGHLANDS AND SHENANDOAH VALLEY NORTHWARD...OR MAINLY NORTH OF I-64. HAVE TAILORED POPS ACCORDINGLY. THU STILL LIKES A DRY AND WARM DAY AS THE UPPER RIDGE DRIFTS OVER THE REGION. FOR FRI-SAT...THE MODELS HAVE COME INTO BETTER AGREEMENT ON THE MOVEMENT OF THE CENTRAL U.S. TROUGH INTO THE EASTERN U.S. THE MAJORITY OF THE PCPN WILL REMAIN WEST OF THE CWA THROUGH FRI...BUT BY SAT LIKELY POPS APPEAR IN ORDER FOR THE WV COUNTIES DOWN THROUGH SW VA/NW NC. THIS SYSTEM STILL OFFERS THE NEXT BEST CHANCE FOR WIDESPREAD RAINFALL FOR THE CWA. TOO FAR OUT TO GET INTO ANY SPECIFIC DETAILS...BUT HIGH CHC TO LOW LIKELY POPS IN ORDER FOR WESTERN AREAS AS INDICATED AND IN AGREEMENT WITH OUR WESTERN NEIGHBORS FOR NEXT SAT. MODELS SHOW A DISTINCT COOLING TREND FOR WED THAT APPEARS CONTRARY TO THE AMPLIFYING RIDGE. HOWEVER...A WEAK WEDGE PATTERN APPEARS EVIDENT UNDER THE AMPLIFYING RIDGE...WHICH COULD TEMPER THE WARMING ALOFT. AGAIN...HAVE GONE WITH A GENERAL MODEL BLEND. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... AS OF 135 AM EDT SUNDAY... ONLY SCATTERED CLOUDS ARE EXPECTED THROUGH MID MORNING WITH NO REDUCTION IN VISIBILITY. A WEAK COLD FRONT WILL SINK SOUTH THIS MORNING AND WILL EXTEND ACROSS KENTUCKY INTO WESTERN VIRGINIA TODAY AND TONIGHT. THIS BOUNDARY WILL PROVIDE SOME LOW LEVEL CONVERGENCE...ENOUGH TO DEVELOP SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. HAVE KEPT SHOWERS IN THE BCB/BLF/LWB AND ROA TAFS AFTER 20Z/4PM TODAY BUT REMOVED THUNDERSTORMS SINCE THE PROBABILITY OF A STORM AT THESE AIRPORTS IS VERY LOW. WINDS WILL BEGIN GUSTING ONCE MORNING INVERSION MIXES OUT...AROUND 13-14Z/9-10AM. HIGH CONFIDENCE THAT WINDS GUSTS FROM 25 TO 30 KNOTS WILL BE COMMON THIS AFTERNOON. WINDS WILL DIMINISH THIS EVENING AROUND SUNSET. TONIGHT INTO WEDNESDAY...THE FRONT WILL STALL NEAR THE VICINITY OF THE FORECAST REGION. IMPULSES ALONG THIS BOUNDARY WILL BRING AN INCREASING CHANCE FOR SUB-VFR CEILINGS AND PERIODS OF SHRA/TSRA. THURSDAY THE FRONT LIFTS NORTH WITH DRIER WX AND WARMER AIR MOVING INTO THE REGION. && .FIRE WEATHER... IN COORDINATION WITH NC FORESTRY OFFICIALS AND SURROUNDING NATIONAL WEATHER SERVICE OFFICES...HAVE ISSUED A SPECIAL WEATHER STATEMENT FOR ENHANCED FIRE DANGER THIS AFTERNOON IN THE NORTH CAROLINA FOOTHILLS. MOST CRITICAL CONDITIONS WILL BE FROM NOON THROUGH 8PM WHEN HUMIDITIES WILL BE AS LOW AS 25 PERCENT AND WIND WILL BE GUSTING FROM THE NORTHWEST AT 20 TO 30 MPH. OVERALL THESE COUNTIES DID NOT RECEIVE HIGH RAINFALL AMOUNTS FROM THE STORM SYSTEM LAST WEEK SO FUELS HAVE BECOME DRY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...KM LONG TERM...RAB AVIATION...AMS FIRE WEATHER...AMS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
230 AM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN MAY 4 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST...RIDGING DOWNSTREAM OVER THE ROCKIES AND WESTERN PLAINS...AND MORE TROUGHING OVER THE GREAT LAKES. ON THE SOUTHWEST SIDE OF THIS GREAT LAKES TROUGH...A 100 KT JET STREAK NEAR 250MB EXTENDED FROM INTERNATIONAL FALLS MN TO TRAVERSE CITY MI PER RAP ANALYSIS. THIS JET STREAK WAS AIDING IN A MID LEVEL FRONTOGENESIS ZONE TO ITS SOUTHWEST OVER THE EASTERN DAKOTAS INTO SOUTHERN MN. EXTENSIVE MID CLOUDS FROM SOUTH DAKOTA EASTWARD TO LOCATIONS SOUTHWEST OF I-94 IN THE FORECAST AREA EXIST AS A RESULT OF THIS FRONTOGENESIS ZONE. RADAR IMAGERY DEPICTS TWO BANDS OF SHOWER ACTIVITY ACROSS SOUTH DAKOTA BUT NO PRECIPITATION HAS BEEN REPORTED DUE TO DRY LOW LEVEL AIR. BANDS ACROSS SOUTHERN SOUTH DAKOTA ACTUALLY PRODUCING SOME LIGHTNING FROM STEEPER MID LEVEL LAPSE RATES COMING OFF THE ROCKIES. 925MB DEWPOINT DEPRESSIONS WERE 10-15C AT 00Z AT BIS...ABR AND MPX...HELPING TO PREVENT RAIN FROM REACHING THE GROUND. ALONG WITH THE DRY AIR...COOLER AIR WAS ADVECTING SOUTHEASTWARD FROM CANADA INTO THE FORECAST AREA. 925MB TEMPS AT BIS AND ABR FELL 5-6C OVER THE PAST 24 HOURS. UPPER RIDGING OVER THE ROCKIES IS PROGGED TO SLIDE FULLY OVER THE PLAINS BY 12Z MONDAY...PUSHED AHEAD BY THE DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST. WITH THE FORECAST AREA STAYING ON THE EAST SIDE OF THE RIDGE AXIS...THIS FAVORS SUBSIDENCE AND DRYING WITH HIGH PRESSURE AT THE SURFACE. HOWEVER...THERE ARE TWO CAVEATS TO THIS GENERALITY. 1. THIS MORNING WITH THE MID-LEVEL FRONTOGENESIS ZONE AND RIGHT ENTRANCE REGION OF THE JET STREAK. MODELS HAVE DEFINITELY TRENDED WEAKER WITH THIS FRONTOGENESIS...EVEN JUST BETWEEN THE 03.18Z AND 04.00Z NAM. AS A RESULT...THE 04.00Z GFS/NAM/REGIONAL CANADIAN HAVE REALLY BACKED OFF ON THE IDEA OF RAIN ACROSS SOUTHERN MN...NORTHERN IA...SOUTHERN WI AND NORTHERN IL THIS MORNING. 04.06Z RAP AND 04.04Z HRRR...WHICH ARE MIMICKING NICELY WHAT HAS BEEN GOING ON IN THE DAKOTAS...ALSO ARE DRIER. THEREFORE...HAVE FOLLOWED SUIT AND REALLY LOWERED PRECIPITATION CHANCES. 2. 04.00Z NAM/REGIONAL CANADIAN/GFS/ECMWF DEPICT ANOTHER BAND OF MID LEVEL FRONTOGENESIS TO TRACK OUT OF NORTH DAKOTA THIS AFTERNOON AND ACROSS LOCATIONS MAINLY NORTH OF I-94 BETWEEN 06-12Z MONDAY. THERE WERE INDICATIONS IN PAST RUNS OF POSSIBLE PRECIPITATION FROM THIS BAND...BUT THE 04.00Z ARE THE MOST IMPRESSIVE THUS FAR. THEREFORE...HAVE ADDED 20 PERCENT CHANCES. STILL HAVE SOME CONCERNS FOR PRECIPITATION GIVEN HIGH PRESSURE PROGGED OVER UPPER MI...WHICH WOULD PROVIDE A FEED OF DRY LOW LEVEL AIR TO COUNTERACT RAIN FALLING TO THE SURFACE. COOLER TEMPERATURES ARE EXPECTED TODAY GIVEN 18Z 925MB TEMPS PROGGED AROUND 4C COMPARED TO 7-10C AT 18Z YESTERDAY. HIGHS SHOULD BE AT LEAST 5 IF NOT 10 DEGREES COOLER...COOLEST OVER NORTHEAST IOWA WITH MOST CLOUD COVER. BATCH OF MID CLOUDS COMING THROUGH WITH THE FRONTOGENESIS ZONE TONIGHT COMBINED WITH AN INCREASING SOUTHEAST 925MB WIND SHOULD HELP TEMPERATURES FROM BOTTOMING OUT TOO MUCH. GUIDANCE LOWS IN THE 30S SEEM REASONABLE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 230 AM CDT SUN MAY 4 2014 BAND OF MID LEVEL FRONTOGENESIS ALONG/NORTH OF I-94 LATE TONIGHT LOOKS TO QUICKLY MOVE OFF TO THE EAST MONDAY MORNING. ONLY THE 04.00Z NAM LINGERS SOME LIGHT RAIN OVER TAYLOR/CLARK COUNTIES AFTER 12Z MONDAY. THEREFORE...HAVE FOLLOWED THE PREVIOUS FORECAST AND KEPT MONDAY DRY FOR NOW. DRY WEATHER IN FACT SHOULD PREVAIL ACROSS MUCH OF THE FORECAST AREA THROUGH TUESDAY AS THE AREA REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE OVER THE WESTERN GREAT LAKES. THE MODERATING TREND IN TEMPERATURES FOR MONDAY THROUGH TUESDAY REMAINS CONSISTENT WITH 925MB READINGS CLIMBING TO 6-8C AT 18Z MONDAY AND 8- 10C AT 18Z TUESDAY. WITH SOME SUN...ESPECIALLY ON TUESDAY...SHOULD SEE HIGHS CLIMB INTO THE MID 50S/LOW 60S ON MONDAY AND LOW TO MID 60S ON TUESDAY. MONDAY NIGHT COULD BE RELATIVELY CHILLY ACROSS CENTRAL WISCONSIN WITH CALM WINDS AND DRY AIR IN PLACE. LOWS THERE MAY DIP CLOSE TO FREEZING. MODELS CONTINUE TO FORECAST AN ACTIVE WEATHER PATTERN FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT...IN RESPONSE TO A BIG PORTION OF A LONG WAVE UPPER TROUGH OVER THE WESTERN U.S. AT 00Z WEDNESDAY LIFTING NORTHEAST INTO THE REGION. THE BIGGEST CHANGE OVER THE LAST 24 HOURS WITH THIS PERIOD OF THE FORECAST IS THAT THE ASSOCIATED LOW PRESSURE SYSTEM LIFTING OUT OF THE CENTRAL PLAINS IS MUCH SLOWER TO CROSS THE AREA THURSDAY INTO THURSDAY NIGHT. A LOT OF THIS SLOWING APPEARS TO BE RELATED TO THE PORTION OF THE LONG WAVE TROUGH TAKING A MORE NORTHWESTWARD TRACK. HIGHLIGHTS... 1. ELEVATED CONVECTION TUESDAY NIGHT / WEDNESDAY MORNING. THIS SIGNAL HAS BEEN VERY CONSISTENT FOR THE PAST COUPLE OF DAYS. INCREASING 850MB MOISTURE TRANSPORT AND CAPE ARE PROGGED TO OCCUR OVER IOWA THROUGH THE NIGHT...NOSING INTO THE FORECAST AREA. SEEMS LIKELY TO AT LEAST GET ELEVATED CONVECTION AND POSSIBLY EVEN AN MCS. SHOULD AN MCS FORM...CORFIDI VECTORS WOULD SUPPORT THE IDEA OF THE 04.00Z NAM OF AN MCS TRACKING EAST-SOUTHEASTWARD ACROSS IOWA. IN ANY EVENT...GIVEN THE CONSISTENT SIGNAL...FELT INCREASE IN PRECIPITATION CHANCES SEEMS WARRANTED. WILL HAVE TO WATCH FOR POTENTIAL SEVERE WEATHER WITH LARGE HAIL THE MOST LIKELY CONCERN. 2. DURING THE DAY WEDNESDAY...04.00Z GFS/ECMWF DEPICT A LOT OF LIGHT PRECIP...MAINLY ALONG AND NORTH OF I-90 WHICH IS ALSO NORTH OF A WARM FRONT. SOUNDINGS SUGGEST THIS IS LOW LEVEL ISENTROPIC LIFT INDUCED BELOW A STRONG CAP...SO PERHAPS AFTER SOME MORNING STORMS WE END UP WITH A BUNCH OF DRIZZLE. THIS IDEA SEEMS REASONABLE WHICH ALSO MEANS A DECENT TEMPERATURE GRADIENT COULD SET UP OVER THE FORECAST AREA. 3. ANOTHER ROUND OF ELEVATED CONVECTION WEDNESDAY NIGHT IF THE 04.00Z GFS IS CORRECT...THOUGH THE 04.00Z ECMWF/CANADIAN SUGGEST THIS CONVECTION WOULD TAKE PLACE WELL NORTH OF THE FORECAST AREA WITH THE AREA UNDER THE 850MB MOISTURE TRANSPORT STREAM. FOR NOW MAINTAINED 20-50 PERCENT CHANCES. WEDNESDAY NIGHT IS LOOKING WARM AND HUMID AS WELL...ESPECIALLY COMPARED TO WHAT WE HAVE SEEN. 4. THURSDAY IS LOOKING MORE MESSY...ESPECIALLY FORECASTING THE HIGH TEMP. MODELS AGREE THE FORECAST AREA IS IN THE WARM SECTOR...WHICH NORMALLY SUGGESTS A CAPPED ATMOSPHERE. HOWEVER...THE 04.00Z ECMWF/CANADIAN/GFS ARE ALL POINTING TO A WARM CONVEYOR BELT OF SHOWERS AND STORMS ACROSS MUCH OF THE FORECAST AREA AHEAD OF THE SHORTWAVE TROUGH LIFTING THROUGH THE PLAINS. 04.00Z ECMWF HAS CUT HIGHS 5-8 DEGREES AS A RESULT. THUS...FOR NOW HAVE LEFT A CONSENSUS HIGH IN THE 70S. STILL...THIS IS MUCH WARMER THAN WHERE WE HAVE BEEN. 5. POSSIBLE SEVERE WEATHER LATE THURSDAY/THURSDAY NIGHT. GIVEN THE NORTHWESTWARD TREND OF THE PLAINS TROUGH...SLOWER COLD FRONTAL TIMING AND THAT WARM CONVEYOR BELT ON THURSDAY LIMITING DAYTIME INSTABILITY...VERY UNCLEAR ON HOW THURSDAY NIGHT WILL PLAY OUT. WOULDNT DOUBT THE FORECAST AREA IS IMPACTED BY STORMS...AND THUS HAVE 50-60 PERCENT CHANCES GOING. HOWEVER...THE TIMING MAY KEEP THE SEVERE CONCERN WEST OF THE AREA. MANY DAYS TO WORK OUT THE DETAILS. MAINTAINED SOME CHANCES FOR FRIDAY WITH POTENTIAL LINGERING SHOWERS ON THE WRAP AROUND OF THE SYSTEM. MUCH COOLER TEMPS FOR FRIDAY TOO. DRIER WEATHER FOLLOWS FOR FRIDAY NIGHT WITH HIGH PRESSURE SLIDING THROUGH...THEN A COLD FRONT LOOKS TO APPROACH FOR SATURDAY TO BRING THE NEXT CHANCE OF RAIN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1149 PM CDT SAT MAY 3 2014 THE 04.00Z NAM STILL SHOWS A WEAK SHORT WAVE TROUGH WILL PASS ACROSS THE AREA SUNDAY. HOWEVER...IT HAS SHIFTED THIS WAVE FARTHER NORTH THAN WHAT THE 03.18Z RUN INDICATED. WATER VAPOR SATELLITE WOULD SUGGEST THE WAVE IS OVER SOUTHEAST MONTANA...WHICH IS FARTHER SOUTH THAN WHAT THE NAM WOULD SUGGEST. THE NAM ALSO TRENDED MUCH WEAKER WITH THE MID LEVEL FRONTOGENESIS THAT DEVELOPS WITH THE PASSAGE OF THE WAVE TO THE POINT THAT ANY SHOWERS WITH THE WAVE MAY NOT EVEN MAKE IT INTO WISCONSIN BEFORE DISSIPATING. THE 04.00Z GFS HAS COME IN WITH A VERY SIMILAR TRACK TO WHAT IT SHOWED WITH ITS 03.18Z RUN AND ALSO WOULD SUGGEST THE SHOWERS WOULD BE DISSIPATING AS THEY COME IN. COULD SEE THESE AS JUST ENOUGH TO WET THE PAVEMENT WET OR SOME SPRINKLES SO HAVE LEFT IN THE VCSH AT BOTH SITES. CEILINGS DURING THE DAY AND INTO SUNDAY EVENING LOOK TO BE VFR WITH A MID LEVEL DECK. && .HYDROLOGY... ISSUED AT 230 AM CDT SUN MAY 4 2014 FLOODING CONTINUES ALONG THE MAINSTEM MISSISSIPPI RIVER AS RUNOFF FROM MELTING SNOW AND ALL OF THE RAINFALL OVER THE PAST 7-10 DAYS MOVES THROUGH THE WATERSHED. MOST OF THE TRIBUTARIES ARE FALLING AND SHOULD CONTINUE TO DO SO THE NEXT FEW DAYS. FOR THE MISSISSIPPI... CRESTS ARE EXPECTED FROM LAKE CITY THROUGH WABASHA AND ALMA ON MONDAY...AND ON TUESDAY FOR WINONA TO LA CROSSE. CRESTS WILL BE WEDNESDAY OR THURSDAY FROM GENOA THROUGH GUTTENBERG. FLOODING WILL REMAIN MINOR...THOUGH WINONA COULD GET CLOSE TO MODERATE FLOOD STAGE. REFER TO THE LATEST FLOOD STATEMENTS FOR DETAILS. NO LARGE RAIN AMOUNTS ARE ANTICIPATED UNTIL PERHAPS LATE TUESDAY NIGHT THROUGH THURSDAY NIGHT. THIS RAIN COULD SLOW THE RATE OF FALL OF THE MISSISSIPPI...BUT AT THIS TIME DOES NOT APPEAR AS IF IT WILL HAVE MUCH INFLUENCE ON THE CREST LEVEL. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04 HYDROLOGY...MW/AJ
AREA FORECAST DISCUSSION...CORRECTED
NWS NEW YORK NY
1114 AM EDT SUN MAY 4 2014 .SYNOPSIS... COLD FRONT APPROACHES AND PASSES THROUGH THE REGION THIS AFTERNOON. HIGH PRESSURE THEN BUILDS DOWN SLOWLY FROM SOUTHERN CANADA THROUGH THE MIDDLE OF NEXT WEEK. A WARM FRONT WILL SLOWLY APPROACH FROM THE SOUTHWEST THURSDAY INTO FRIDAY...THEN LIFT TO THE NORTH FRIDAY NIGHT. A COLD FRONT APPROACHES FROM THE WEST ON SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MADE SOME CHANGES WITH THIS UPDATE. FIRST REGARDING CLOUD COVER...TRICKY TO DEPICT TRENDS IN THE CLOUD COVER GRIDS ACROSS THE AREA AS GENERALLY VARYING AMOUNTS OF CLOUDS WILL BE SEEN THROUGH THE DAY. BIGGEST ADJUSTMENT WAS TO BUMP UP CLOUD COVER TO MOSTLY CLOUDY FOR SOUTHERN ZONES FOR THE DURATION OF THIS MORNING BASED ON LATEST SATELLITE TRENDS. FOR TEMPERATURES...ADJUSTED HIGHS UPWARD A COUPLE OF DEGREES MAINLY ACROSS LONG ISLAND AND PARTS OF SE CT BASED ON CURRENT 850MB TEMP AND A MODERATE WESTERLY FLOW. DEWPOINTS NEEDED TO BE ADJUSTED DOWNWARD AS DRIER AIR FROM ALOFT MIXES DOWN...NOTING FALLING DEWPOINTS AT 850MB AS WELL. AS FOR POPS...A FEW FACTORS COME INTO PLAY...AND AM NOT CONFIDENT ENOUGH THAT ALL INGREDIENTS COME TOGETHER AT ANY LOCATION AT ANY POINT IN TIME TO WARRANT LIKELY POPS. THEREFORE HAVE THE ENTIRE AREA AT HIGHER-END CHANCE POPS THIS AFTERNOON. LIFT WILL BE GOOD AS A COLD FRONT/SURFACE TROUGH MOVES THROUGH THIS AFTERNOON. AT THE SAME TIME...PVA FROM AN APPROACHING SHORTWAVE ALOFT AND SYNOPTIC LIFT FROM A JET STREAK WILL ENHANCE OVERALL LIFT. THE PROBLEM IS THAT THERE APPEARS TO BE SHORT WINDOW THIS AFTERNOON WHERE THIS LIFT WILL BE ABLE TO WORK WITH SUFFICIENT MOISTURE TO PRODUCE SHOWERS. DEW POINTS WILL BE IN THE 30S AND CAPE WILL BE VERY LOW...BUT SINCE THE AFOREMENTIONED LIFT WILL BE OCCURRING AT A TIME WHERE MID LEVEL LAPSE RATES WILL BE CONDITIONALLY UNSTABLE...AND ALMOST STRONGLY UNSTABLE FOR SOME SPOTS (MAINLY EASTERN ZONES WHERE COLD POOL ALOFT WILL BE MORE SIGNIFICANT)...WILL KEEP IN AN ISOLATED THUNDERSTORM IN THE FORECAST. THE PAST FEW RUNS OF HRRR AND RAP13 HAVE BEEN KEYING IN ON THE SOUTHERN ZONES FOR THE BEST CHANCES OF SHOWERS...APPARENTLY DUE TO MOISTURE CONVERGENCE ALONG THE COLD FRONT/TROUGH. WITH THE RELATIVELY DRY LOWER LEVELS...AND A MEAN OF AROUND 30KT WINDS IN THE BOUNDARY LAYER...ANY HEAVIER SHOWERS COULD PRODUCE WIND GUSTS PERHAPS AS HIGH AS AROUND 50MPH. OUTSIDE OF SHOWERS...DEEP MIXING WILL ALLOW FOR WESTERLY GUSTS OF 30-40 MPH. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... COLD FRONT CLEARS THE REGION BY THIS EVENING...TAPERING OFF ANY PRECIPITATION CHANCES BY THE END OF THE EVENING. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE BEFORE 00Z...WITH INSTABILITY DIMINISHING AND THE UPPER LEVEL FORCING PUSHING ON TO THE SOUTH. THE UPPER LEVEL CLOSED LOW PUSHES OFF TO THE EAST...BUT KEEPS THE REGION UNDER A BROAD TROUGH AND CYCLONIC FLOW ON THROUGH MONDAY. THIS WILL DO LITTLE MORE THAN KEEP THE MENTION OF PARTLY CLOUDY SKIES IN THE FORECAST AS HIGH PRESSURE BUILDING IN FROM THE NORTH WILL HELP TO DRY THE REGION. AS THE HIGH BUILDS IN...PRESSURE GRADIENT REMAINS TIGHT TONIGHT...AND COMBINING WITH A SHOT OF CAA WITH THE NORTHWESTERLY FLOW...WILL HELP TO KEEP WINDS ELEVATED THROUGH THE NIGHT. AS THE GRADIENT SLACKENS MONDAY WITH THE HIGH BECOMING THE MORE DOMINATING FEATURE...WINDS WILL DIMINISH. DESPITE COOLER TEMPERATURES MOVING IN...STILL EXPECTING TEMPS TO REMAIN NEAR NORMAL IN THE 60S FOR THE AREA. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... CLOSED LOW SLOWLY DEPARTS TO THE E FROM THE CANADIAN MARITIMES MONDAY-TUESDAY. WILL HAVE DOWNSLOPE NW FLOW...BUT CYCLONIC CURVATURE AROUND DEPARTING CUTOFF SHOULD ALLOW FOR A FEW CLOUDS. DEEP LAYERED RIDGE BUILDS TOWARDS THE AREA FROM TUESDAY NIGHT- FRIDAY...THEN SLIDES TO THE EAST INTO SATURDAY. ASSOCIATED SUBSIDENCE SHOULD KEEP THINGS DRY...AND WITH MINIMAL CLOUD COVER TUESDAY NIGHT-WEDNESDAY. FORECAST THEN BECOMES A BIT TRICKY WEDNESDAY NIGHT-SATURDAY. A STALLED FRONTAL BOUNDARY OVER THE MID-SOUTH AND SOUTHEAST IN THE MIDDLE OF THE WEEK...LIFTS NE AS A WARM FRONT STARTING WEDNESDAY NIGHT...AS ONSHORE RETURN FLOW DEVELOPS OVER THE AREA. SO SHOULD BEGIN TO SEE INCREASE IN CLOUDS AHEAD OF THE WARM FRONT FROM SW TO NE WEDNESDAY NIGHT. MODELS DIFFER OVER HOW QUICKLY TO BRING IN ANY RAIN ON THURSDAY - FIGURE THAT SUBSIDENCE UNDER THE BUILDING RIDGE SHOULD SERVE AS A LIMITING FACTOR. SO HAVE RESTRICTED CHANCE POPS TO THE AFTERNOON...AND THEN ONLY OVER THE SW 2/3 OF THE CWA. DOES APPEAR SOLID AGREEMENT THAT SHOULD SEE SOME RAIN THURSDAY NIGHT - SO HAVE CHANCE POPS THROUGHOUT. ECMWF AND GFS BOTH HAVE WARM FRONT STAYING TO THE S THROUGH THE DAY ON FRIDAY...SO SHOULD BE A GREY DAMP/POSSIBLY WET DAY - WITH SUBSIDENCE UNDER THE RIDGE A MITIGATING FACTOR - PLUS SHOULD BE ON THE COOL SIDE DUE TO CLOUD COVER/PRECIP AND E LOW LEVEL FLOW. CONTINUE TO FOLLOW CONSENSUS IDEA OF WARM FRONT LIFTING TO THE N FRIDAY NIGHT...LIKE THE LAST SYSTEM...BUT WOULD NOT BE SURPRISED IF IT ENDED UP DELAYING UNTIL SATURDAY MORNING. COLD FRONT STAYS TO THE WEST THROUGH THE DAY ON SATURDAY...SO SHOULD BE SOLIDLY IN THE WARM SECTOR THEN. NOTING IN WARM SECTOR ON SATURDAY...PLUS FORECAST SHOWALTER INDICES NEAR TO BELOW ZERO FRIDAY NIGHT AND SATURDAY - HAVE PUT A SLIGHT CHANCE OF THUNDER IN BOTH PERIODS TO GO WITH THE CHANCE OF SHOWERS. FOR TEMPERATURES TUESDAY NIGHT-SATURDAY USED A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE. ALSO BLENDED IN ECMWF 2-METER TEMPERATURES ON FRIDAY TO REFLECT IMPACT OF ONSHORE FLOW/CLOUD COVER/PRECIP. HAVE A FEELING THAT IF THINGS PLAY OUT AS CURRENTLY FORECAST...THAT WILL ULTIMATELY END UP STRUGGLING TO GET TEMPERATURES OUT OF THE 50S ON FRIDAY - FOR NOW WENT MAINLY IN THE 60S. FOR NOW GOING WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TUESDAY NIGHT-FRIDAY (WITH CAVEAT FOR FRIDAY AS STATED ABOVE)...THEN ABOVE NORMAL TEMPERATURES FRIDAY NIGHT AND SATURDAY. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... A COLD FRONT WILL MOVE ACROSS BY THIS EVENING. CU ARE STARTING TO DEVELOP AHEAD OF THE FRONT OVER THE LOWER HUDSON VALLEY AND CT...AND IT APPEARS A BKN LINE OF SHOWERS AND ISOLD TSTMS SHOULD DEVELOP OVER OR JUST NORTH OF THE NYC METRO AND LONG ISLAND TERMINALS BY ABOUT 18Z...AND SLOWLY SPREAD SOUTH THROUGH THE REST OF THE AFTERNOON. CONFIDENT ENOUGH TO CONTINUE MENTION OF TEMPO MVFR CONDS...BUT IMPACTS COULD INCLUDE STRONG WIND GUSTS TO 40-45 KT IF A STRONGER CELL MOVES DIRECTLY OVERHEAD. IMPACTS FROM SHOWERS NOW LOOK LOWER TO THE NORTH ACROSS THE LOWER HUDSON VALLEY AND CT...BUT CANNOT RULE OUT WIDELY SCT ACTIVITY THERE ESPECIALLY ACROSS CT. W FLOW GUSTING AT OR JUST OVER 30 KT AT THE NYC METRO TERMINALS...AND 25-30 KT ELSEWHERE...SHOULD BACK NW THIS EVENING AFTER COLD FROPA...REMAINING LEFT OF 310 MAGNETIC. WINDS ONLY SLIGHTLY WEAKEN TONIGHT WITH GUSTS REMAINING. .OUTLOOK FOR 12Z MON THROUGH THU... .MON...VFR. NW WINDS G25KT...DIMINISHING IN THE AFTERNOON/EVENING. .MON NIGHT-WED NIGHT...VFR. .THU...CHANCE OF MVFR CONDS IN ANY RAIN. && .MARINE... WINDS AND WAVE FORECAST REMAIN ON TRACK. MINIMAL MIXING ON THE WATERS WILL HELP TO MINIMIZE THE GUSTS FARTHER OFFSHORE...WITH THE HIGHER GUSTS EXPECTED ALONG THE COASTS AND ACROSS THE BAYS OF LONG ISLAND WHERE BETTER MIXING WILL OCCUR. OVERALL...EXPECTING GUSTS TO 25 KT EVERYWHERE...WITH POSSIBLE 30 KT RIGHT AT THE COAST THROUGH TONIGHT. SEAS WILL BUILD ON THE OCEAN WATERS TO BETWEEN 4 AND 6 FT. THE SCA CONDITIONS ARE EXPECTED TO DIMINISH BY MONDAY MORNING AS THE PRESSURE GRADIENT RELAXES WITH THE HIGH BUILDING IN. FORECAST KEEPS ALL WATERS THEN BELOW SCA CONDITIONS FOR THE REMAINDER OF THE WEEK. && .HYDROLOGY... NO SIGNIFICANT RAINFALL IS EXPECTED THROUGH THU. THERE IS THE POSSIBILITY OF SIGNIFICANT RAINFALL FROM THURSDAY NIGHT INTO SATURDAY. AT THIS TIME...THERE IS TOO MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR POTENTIAL IMPACTS. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ330-335-338- 340-345-355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT/SEARS NEAR TERM...JC/SEARS SHORT TERM...SEARS LONG TERM...MALOIT/SEARS AVIATION...GOODMAN/JM MARINE...SEARS/PW HYDROLOGY...SEARS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1028 AM EDT SUN MAY 4 2014 .SYNOPSIS... COLD FRONT APPROACHES AND PASSES THROUGH THE REGION THIS AFTERNOON. HIGH PRESSURE THEN BUILDS DOWN SLOWLY FROM SOUTHERN CANADA THROUGH THE MIDDLE OF NEXT WEEK. A WARM FRONT WILL SLOWLY APPROACH FROM THE SOUTHWEST THURSDAY INTO FRIDAY...THEN LIFT TO THE NORTH FRIDAY NIGHT. A COLD FRONT APPROACHES FROM THE WEST ON SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MADE SOME CHANGES WITH THIS UPDATE. FIRST REGARDING CLOUD COVER...TRICKY TO DEPICT TRENDS IN THE CLOUD COVER GRIDS ACROSS THE AREA AS GENERALLY VARYING AMOUNTS OF CLOUDS WILL BE SEEN THROUGH THE DAY. BIGGEST ADJUSTMENT WAS TO BUMP UP CLOUD COVER TO MOSTLY CLOUDY FOR SOUTHERN ZONES FOR THE DURATION OF THIS MORNING BASED ON LATEST SATELLITE TRENDS. FOR TEMPERATURES...ADJUSTED HIGHS UPWARD A COUPLE OF DEGREES MAINLY ACROSS LONG ISLAND AND PARTS OF SE CT BASED ON CURRENT 850MB TEMP AND A MODERATE WESTERLY FLOW. DEWPOINTS NEEDED TO BE ADJUSTED DOWNWARD AS DRIER AIR FROM ALOFT MIXES DOWN...NOTING FALLING DEWPOINTS AT 850MB AS WELL. AS FOR POPS...A FEW FACTORS COME INTO PLAY...AND AM NOT CONFIDENT ENOUGH THAT ALL INGREDIENTS COME TOGETHER AT ANY LOCATION AT ANY POINT IN TIME TO WARRANT LIKELY POPS. THEREFORE HAVE THE ENTIRE AREA AT HIGHER-END CHANCE POPS THIS AFTERNOON. LIFT WILL BE GOOD AS A COLD FRONT/SURFACE TROUGH MOVES THROUGH THIS AFTERNOON. AT THE SAME TIME...PVA FROM AN APPROACHING SHORTWAVE ALOFT AND SYNOPTIC LIFT FROM A JET STREAK WILL ENHANCE OVERALL LIFT. THE PROBLEM IS THAT THERE APPEARS TO BE SHORT WINDOW THIS AFTERNOON WHERE THIS LIFT WILL BE ABLE TO WORK WITH SUFFICIENT MOISTURE TO PRODUCE SHOWERS. DEW POINTS WILL BE IN THE 30S AND CAPE WILL BE VERY LOW...BUT SINCE THE AFOREMENTIONED LIFT WILL BE OCCURRING AT A TIME WHERE MID LEVEL LAPSE RATES WILL BE CONDITIONALLY UNSTABLE...AND ALMOST STRONGLY UNSTABLE FOR SOME SPOTS (MAINLY EASTERN ZONES WHERE COLD POOL ALOFT WILL BE MORE SIGNIFICANT)...WILL KEEP IN AN ISOLATED THUNDERSTORM IN THE FORECAST. THE PAST FEW RUNS OF HRRR AND RAP13 HAVE BEEN KEYING IN ON THE SOUTHERN ZONES FOR THE BEST CHANCES OF SHOWERS...APPARENTLY DUE TO MOISTURE CONVERGENCE ALONG THE COLD FRONT/TROUGH. WITH THE RELATIVELY DRY LOWER LEVELS...AND A MEAN OF AROUND 30KT WINDS IN THE BOUNDARY LAYER...ANY HEAVIER SHOWERS COULD PRODUCE WIND GUSTS PERHAPS AS HIGH AS AROUND 50MPH. OUTSIDE OF SHOWERS...DEEP MIXING WILL ALLOW FOR WESTERLY GUSTS OF 30-40 MPH. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... COLD FRONT CLEARS THE REGION BY THIS EVENING...TAPERING OFF ANY PRECIPITATION CHANCES BY THE END OF THE EVENING. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE BEFORE 00Z...WITH INSTABILITY DIMINISHING AND THE UPPER LEVEL FORCING PUSHING ON TO THE SOUTH. THE UPPER LEVEL CLOSED LOW PUSHES OFF TO THE EAST...BUT KEEPS THE REGION UNDER A BROAD TROUGH AND CYCLONIC FLOW ON THROUGH MONDAY. THIS WILL DO LITTLE MORE THAN KEEP THE MENTION OF PARTLY CLOUDY SKIES IN THE FORECAST AS HIGH PRESSURE BUILDING IN FROM THE NORTH WILL HELP TO DRY THE REGION. AS THE HIGH BUILDS IN...PRESSURE GRADIENT REMAINS TIGHT TONIGHT...AND COMBINING WITH A SHOT OF CAA WITH THE NORTHWESTERLY FLOW...WILL HELP TO KEEP WINDS ELEVATED THROUGH THE NIGHT. AS THE GRADIENT SLACKENS MONDAY WITH THE HIGH BECOMING THE MORE DOMINATING FEATURE...WINDS WILL DIMINISH. DESPITE COOLER TEMPERATURES MOVING IN...STILL EXPECTING TEMPS TO REMAIN NEAR NORMAL IN THE 60S FOR THE AREA. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... CLOSED LOW SLOWLY DEPARTS TO THE E FROM THE CANADIAN MARITIMES MONDAY-TUESDAY. WILL HAVE DOWNSLOPE NW FLOW...BUT CYCLONIC CURVATURE AROUND DEPARTING CUTOFF SHOULD ALLOW FOR A FEW CLOUDS. DEEP LAYERED RIDGE BUILDS TOWARDS THE AREA FROM TUESDAY NIGHT- FRIDAY...THEN SLIDES TO THE EAST INTO SATURDAY. ASSOCIATED SUBSIDENCE SHOULD KEEP THINGS DRY...AND WITH MINIMAL CLOUD COVER TUESDAY NIGHT-WEDNESDAY. FORECAST THEN BECOMES A BIT TRICKY WEDNESDAY NIGHT-SATURDAY. A STALLED FRONTAL BOUNDARY OVER THE MID-SOUTH AND SOUTHEAST IN THE MIDDLE OF THE WEEK...LIFTS NE AS A WARM FRONT STARTING WEDNESDAY NIGHT...AS ONSHORE RETURN FLOW DEVELOPS OVER THE AREA. SO SHOULD BEGIN TO SEE INCREASE IN CLOUDS AHEAD OF THE WARM FRONT FROM SW TO NE WEDNESDAY NIGHT. MODELS DIFFER OVER HOW QUICKLY TO BRING IN ANY RAIN ON THURSDAY - FIGURE THAT SUBSIDENCE UNDER THE BUILDING RIDGE SHOULD SERVE AS A LIMITING FACTOR. SO HAVE RESTRICTED CHANCE POPS TO THE AFTERNOON...AND THEN ONLY OVER THE SW 2/3 OF THE CWA. DOES APPEAR SOLID AGREEMENT THAT SHOULD SEE SOME RAIN THURSDAY NIGHT - SO HAVE CHANCE POPS THROUGHOUT. ECMWF AND GFS BOTH HAVE WARM FRONT STAYING TO THE S THROUGH THE DAY ON FRIDAY...SO SHOULD BE A GREY DAMP/POSSIBLY WET DAY - WITH SUBSIDENCE UNDER THE RIDGE A MITIGATING FACTOR - PLUS SHOULD BE ON THE COOL SIDE DUE TO CLOUD COVER/PRECIP AND E LOW LEVEL FLOW. CONTINUE TO FOLLOW CONSENSUS IDEA OF WARM FRONT LIFTING TO THE N FRIDAY NIGHT...LIKE THE LAST SYSTEM...BUT WOULD NOT BE SURPRISED IF IT ENDED UP DELAYING UNTIL SATURDAY MORNING. COLD FRONT STAYS TO THE WEST THROUGH THE DAY ON SATURDAY...SO SHOULD BE SOLIDLY IN THE WARM SECTOR THEN. NOTING IN WARM SECTOR ON SATURDAY...PLUS FORECAST SHOWALTER INDICES NEAR TO BELOW ZERO FRIDAY NIGHT AND SATURDAY - HAVE PUT A SLIGHT CHANCE OF THUNDER IN BOTH PERIODS TO GO WITH THE CHANCE OF SHOWERS. FOR TEMPERATURES TUESDAY NIGHT-SATURDAY USED A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE. ALSO BLENDED IN ECMWF 2-METER TEMPERATURES ON FRIDAY TO REFLECT IMPACT OF ONSHORE FLOW/CLOUD COVER/PRECIP. HAVE A FEELING THAT IF THINGS PLAY OUT AS CURRENTLY FORECAST...THAT WILL ULTIMATELY END UP STRUGGLING TO GET TEMPERATURES OUT OF THE 50S ON FRIDAY - FOR NOW WENT MAINLY IN THE 60S. FOR NOW GOING WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TUESDAY NIGHT-FRIDAY (WITH CAVEAT FOR FRIDAY AS STATED ABOVE)...THEN ABOVE NORMAL TEMPERATURES FRIDAY NIGHT AND SATURDAY. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... A COLD FRONT MOVES ACROSS BY THIS EVENING. MAINLY VFR EXPECTED THROUGH TAF PERIOD WITH ONLY EXCEPTION BEING IN ANY SHRA/TSRA THIS AFTERNOON INTO EARLY EVE WITH POSSIBLE BRIEF REDUCTION DOWN TO MVFR. TEMPO GROUP PLACED DURING TIMEFRAME OF HIGHEST CHANCE...GENERALLY 18-22Z WHICH COULD BE A FEW HRS OFF. THE COVERAGE OF SHRA EXPECTED TO BE MAINLY SCATTERED COVERAGE WITH NUMEROUS COVERAGE FOR WESTERN TERMINALS. TSRA COVERAGE EXPECTED TO REMAIN ISOLATED. DIFFICULT TO PINPOINT EXACTLY WHERE ANY TSRA WOULD FORM...BUT ANY TSRA FORMING COULD ALSO BRING BRIEF GUSTY WINDS HIGHER THAN FCST. A WESTERLY FLOW GRADUALLY INCREASES THROUGH THE TAF PERIOD AND BECOMES MORE NORTHWEST TONIGHT. WINDS INCREASE TO 15-20 KT DURING THE DAY WITH GUSTS NEAR 30 KT...POSSIBLY HIGHER IN ANY TSRA. WINDS ONLY SLIGHTLY WEAKEN TONIGHT WITH GUSTS REMAINING. .OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY... .MON...VFR. NW GUSTS AROUND 25 KT LOWERING MON AFTN-MON EVE. .MON NIGHT-WED NIGHT...VFR. .THU...MOSTLY VFR. CHC -RA/MVFR. && .MARINE... WINDS AND WAVE FORECAST REMAIN ON TRACK. MINIMAL MIXING ON THE WATERS WILL HELP TO MINIMIZE THE GUSTS FARTHER OFFSHORE...WITH THE HIGHER GUSTS EXPECTED ALONG THE COASTS AND ACROSS THE BAYS OF LONG ISLAND WHERE BETTER MIXING WILL OCCUR. OVERALL...EXPECTING GUSTS TO 25 KTS EVERYWHERE...WITH POSSIBLE 30 KTS RIGHT AT THE COAST THROUGH TONIGHT. SEAS WILL BUILD ON THE OCEAN WATERS TO BETWEEN 4 AND 6 FT. THE SCA CONDITIONS ARE EXPECTED TO DIMINISH BY MONDAY MORNING AS THE PRESSURE GRADIENT RELAXES WITH THE HIGH BUILDING IN. FORECAST KEEPS ALL WATERS THEN BELOW SCA CONDITIONS FOR THE REMAINDER OF THE WEEK. && .HYDROLOGY... NO SIGNIFICANT RAINFALL IS EXPECTED THROUGH THU. THERE IS THE POSSIBILITY OF SIGNIFICANT RAINFALL FROM THURSDAY NIGHT INTO SATURDAY. AT THIS TIME...THERE IS TOO MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR POTENTIAL IMPACTS. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ330-335-338- 340-345-355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT/SEARS NEAR TERM...JC/SEARS SHORT TERM...SEARS LONG TERM...MALOIT/SEARS AVIATION...JM MARINE...SEARS/PW HYDROLOGY...SEARS
AREA FORECAST DISCUSSION
NWS ALBANY NY
633 AM EDT SUN MAY 4 2014 .SYNOPSIS... ANOTHER COOL AND UNSETTLED WEATHER REGIME TODAY AS AN UPPER LEVEL LOW PRESSURE SYSTEM IMPACTS THE REGION. A GRADUAL IMPROVEMENT IN THE WEATHER AND MODERATING TEMPERATURES ARE EXPECTED THROUGH THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM EDT...SHOWERS HAVE QUICKLY INCREASED IN COVERAGE AND INTENSITY ACROSS THE DACKS AS UPPER LOW WAS CENTERED IN THE VICINITY OF THE TUG HILL PLATEAU. HRRR AND LOCAL HIRESWRF REFLECTIVITY FORECASTS CONTINUE TO SUGGEST A RAPID INCREASE IN SHOWER ACTIVITY THROUGH THE MORNING HOURS WITH THE HIGHEST CONCENTRATION REMAINING ACROSS THE DACKS. LATEST IR AND 11U-3.9U SATELLITE IMAGERY SUGGEST SOME BREAKS IN THE OVERCAST ACROSS THE SOUTHERN TIER OF NY WHICH WAS ADVANCING INTO THE CATSKILLS...CAPITAL REGION AND PORTIONS OF THE MID HUDSON RIVER VALLEY. HOWEVER...AS SEEN IN THE H2O VAPOR IMAGERY THIS MORNING...AN ELONGATED AND DOUBLE BARREL UPPER LOWS WILL KEEP THE CYCLONIC FLOW ACROSS THE REGION THROUGH THE NEAR TERM. THIS SHOULD RESULT IN SUNSHINE QUICKLY BEING FILLED IN WITH CLOUD COVER AND THE PROBABILITIES OF SHOWERS INCREASING. LATEST SHORT TERM HI-RES MODEL OUTPUTS SUGGEST MOST OF THE PRECIP TODAY WILL OCCUR ACROSS THE ADIRONDACKS...LAKE GEORGE SARATOGA REGION AND INTO SOUTHERN VERMONT. THIS WILL BE A COMBINATION OF FAVORABLE UPSLOPE CONDITIONS AND HIGHER THETA-E AIR WRAPPING AROUND THIS UPPER LOW. AS FOR CHANCE OF THUNDER...WITH THE UPPER LOW TRACKING NORTH AND EAST AWAY FROM THE REGION AND INCREASING SHOWALTER VALUES...SEEMS THE POTENTIAL FOR THUNDER IS DIMINISHING. HOWEVER...WITH SUCH COLDER TEMPERATURES ALOFT /H500 TEMPS DOWN WELL INTO THE NEGATIVE 20S/ AND THAT MAY SUN ANGLE...CHANCE STILL EXISTS WITHIN DEEPER CONVECTIVE ELEMENTS FOR SOME GRAUPAL/SMALL- HAIL AS WE WILL RETAIN THE PREVIOUS FORECAST TO ACCOUNT FOR THIS POSSIBILITY. OTHERWISE...SURFACE GRADIENT INCREASES WITH WIND MAGNITUDES ON THE INCREASE. PER FORECAST MIXING LAYER HEIGHTS...WINDS ACROSS THE HIGHER TERRAIN WILL BE PUSHING UP TO ADVISORY LEVELS. PER COORDINATION...WE WILL WITHHOLD ANY HEADLINES AND MONITOR TRENDS CLOSELY. EITHER WAY...A COOL AND DAMP DAY IS SETTING UP WITH THE BEST CHANCE FOR RAIN ALONG AND NORTH OF I90. DIURNALLY DRIVEN SHOWER ACTIVITY WILL DIMINISH WITH SUNSET...WITH THE EXCEPTION OF THE DACKS EXTENDING INTO THE SOUTHERN GREENS WHERE FAVORABLE UPSLOPE CONDITIONS WITH DEEPER MOISTURE PROFILES TO KEEP THE MENTION OF SHOWERS IN THE FORECAST. IN FACT...AS THE THERMAL PROFILES COOL WITH H850 TEMPS DROPPING BACK AT OR BELOW 0C...COULD SEE SOME SNOW MIXING IN ACROSS THE HIGHER TERRAIN. HIGHS TODAY WILL AVERAGE A GOOD FIVE DEGREES COOLER THAN SATURDAYS WITH TONIGHTS LOWS DROPPING DOWN INTO THE 30S FOR THE HIGHER TERRAIN AND LOWER 40S FOR VALLEY LOCATIONS. OUR NORMAL HIGHS SHOULD BE WELL INTO THE 50S FOR THE TERRAIN AND MID 60S FOR VALLEY LOCATIONS WITH OVERNIGHT LOWS INTO THE UPPER 30S AND MIDDLE 40S. && .SHORT TERM /MONDAY THROUGH TUESDAY/... THIS CYCLONIC FLOW AND UPPER LOW IS RATHER PROGRESSIVE AND WILL DEPART OUR REGION DURING MONDAY. SOME RESIDUAL UPSLOPE CLOUDS AND ISOLATED SHOWERS MAY LINGER...BUT IMPROVEMENTS ARE EXPECTED DURING THE SHORT TERM. THERE WILL BE A VARIABLE AMOUNT OF CLOUD COVER WITH THE COMBINATION OF DIURNALLY DRIVEN AND ANOTHER SHORT WAVE FORECAST TO MOVE ACROSS THE REGION MONDAY NIGHT. HOWEVER...LOWER LEVELS ARE EXPECTED TO DRY OUT WHICH WILL LIMIT ANY ADDITIONAL POTENTIAL FOR SHOWERS. AS SOME PARTIAL SUNSHINE RETURNS ON MONDAY...THE H850 TEMPS ARE FORECAST TO HOVER CLOSE TO 0C. THIS WILL RESULT IN HIGH TEMPERATURES STILL BELOW NORMAL FOR THIS TIME OF THE YEAR WITH 50S FOR THE TERRAIN AND LOWER 60S FOR THE VALLEY LOCATIONS. AS NORTHWEST FLOW REGIME REMAINS IN PLACE...MOISTURE PROFILES CONTINUE TO DRY OUT AS SURFACE PRESSURES CONTINUE TO CLIMB. THIS SHOULD RESULT IN A NICE SPRING DAY FOR THE REGION WITH INCREASING AMOUNTS OF SUNSHINE AND A NEAR RETURN TO SEASONABLE TEMPERATURES. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AT THE START OF THE PERIOD...AN AREA OF HIGH PRESSURE WILL BE PASSING OVER THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. WITH CLEAR SKIES AND LIGHT WINDS...GOOD RADIATIONAL COOLING WILL TAKE PLACE ON TUESDAY NIGHT...ALLOWING FOR A CHILLY NIGHT. MIN TEMPS LOOK TO DROP INTO THE 30S ACROSS THE ENTIRE AREA...WITH SOME UPPER 20S POSSIBLE OVER THE ADIRONDACKS. WITH THE GROWING SEASON HAVING ALREADY STARTED IN THE HUDSON VALLEY ON MONDAY...FROST OR FREEZE HEADLINES COULD BE NEEDED FOR SOME OF THE TYPICAL COOLER SPOTS IN THE HUDSON VALLEY FOR TUESDAY NIGHT. DRY AND PLEASANT WEATHER WILL BE IN PLACE FOR WEDNESDAY. WITH THE SFC HIGH PRESSURE AREA STARTING TO SHIFT EASTWARD...AND 850 HPA TEMPS RISING TO AS HIGH AS 6 DEGREES C...TEMPS ON WEDNESDAY WILL BE WARMER THAN RECENT DAYS...WITH MID TO UPPER 60S FOR VALLEY AREAS /UPPER 50S TO LOW 60S FOR THE HIGH TERRAIN/. IT WILL REMAIN DRY INTO WEDNESDAY NIGHT. HOWEVER...WITH A SOUTHERLY FLOW IN PLACE AND SOME CLOUDS STARTING TO ARRIVE FROM THE SOUTH AND WEST...WED NIGHT MINS WON/T BE AS COOL...WITH UPPER 30S TO MID 40S OVER THE REGION. ALONG WITH RISING 500 HPA HEIGHTS AND WARMING TEMPS ALOFT...A SFC WARM FRONT WILL BE APPROACHING FOR THURSDAY AND INTO FRIDAY. THIS WILL START TO INTRODUCE THE CHANCE FOR SOME RAIN SHOWERS...ESP BY THURS NIGHT INTO FRIDAY. THIS FRONT MAY GET HUNG UP OVER THE AREA BEFORE THE STORM/S COLD FRONT PASSES OVER THE REGION DURING THE WEEKEND...SO IT/S POSSIBLE THAT THE THREAT FOR SHOWERS WILL LINGER INTO THE WEEKEND AS WELL. HOWEVER...THE WARMER TEMPS ALOFT /850 HPA TEMPS OF 10-11 DEGREES C BY FRIDAY AND SATURDAY/ AND SOUTHERLY FLOW AT LOW LEVELS WILL ALLOW FOR WARMER TEMPS THAN RECENT DAYS...ESP IF ANY BREAKS IN THE CLOUDS OCCUR. MAX TEMPS FOR VALLEY AREAS FOR THURS THROUGH SATURDAY LOOK TO REACH INTO THE UPPER 60S TO LOW 70S...WITH MID 60S FOR THE HILLS AND MOUNTAINS. OVERNIGHT LOWS WILL RANGE FROM THE MID 40S TO MID 50S FOR THURS/FRI NIGHTS AS WELL. AT THIS POINT...WE EXPECT CLOUDS AND POSSIBLE PRECIP TO LIMIT THE FULL POTENTIAL OF WARMING...BUT IF THE REGION WERE TO TRULY WARM SECTOR...IT COULD BE EVEN WARMER THAN CURRENTLY FORECAST. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... DURING THE DAY TODAY...A POTENT UPPER LEVEL SHORTWAVE TROUGH WILL MOVE JUST NORTH OF THE AREA. WITH COOL TEMPS ALOFT...THIS WILL ALLOW FOR THE THREAT OF A SHOWER DURING THE DAY...ESP FOR KGFL. ALTHOUGH CIGS EARLY THIS MORNING WILL BE SCT...DAYTIME HEATING WILL CAUSE CLOUDS TO DEVELOP...WITH BKN CIGS AROUND 4-6 KFT BY LATER THIS MORNING. ALTHOUGH FLYING CONDITIONS WILL GENERALLY BE VFR THROUGHOUT THE DAY...A BRIEF REDUCTION TO MVFR CANNOT BE RULED OUT WITHIN ANY RAIN SHOWER...AND A TEMPO TO ACCOUNT FOR THIS HAS BEEN INCLUDED AT KGFL...WHERE IT IS MORE LIKELY TO OCCUR. ELSEWHERE...VCSH WILL BE MENTIONED AT THE OTHER TAF SITES TO ACCOUNT FOR THE POSSIBILITY OF A BRIEF RAIN SHOWER NEARBY. IN ADDITION...THE COOL TEMPS ALOFT WILL PROMOTE GOOD MIXING...WHICH WILL ALLOW FOR GUSTY WINDS. WESTERLY WINDS WILL BE AROUND 15-20 KTS BY LATE THIS MORNING AND INTO THIS AFTN...WITH A FEW GUTS AS HIGH AS 30 KTS AT KALB. WINDS WILL DIMINISH SLIGHTLY BY SUNSET...WITH IT WILL REMAIN BREEZY INTO TONIGHT WITH A CONTINUED THREAT FOR A RAIN SHOWER THROUGH THE LATE EVENING HOURS AND BKN-CIGS REMAINING AROUND 5 KFT. THE THREAT FOR SHOWERS WILL END BY LATE TONIGHT...AS THE UPPER LEVEL SHORTWAVE MOVES AWAY FROM THE AREA. OUTLOOK... MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. TUESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... ANOTHER COOL AND UNSETTLED CONDITIONS ARE FORECAST TODAY...AS A SERIES OF UPPER LEVEL DISTURBANCES MOVES ACROSS THE REGION.THIS WILL BRING AN INCREASED CHANCE FOR SHOWERS AND POSSIBLE THUNDERSTORM...ESPECIALLY DURING THE AFTERNOON AND EVENING HOURS. DRIER WEATHER RETURNS FOR EARLY THIS WEEK. && .HYDROLOGY... NO HYDROLOGIC PROBLEMS ARE EXPECTED DURING THE NEXT 5 DAYS. SCATTERED RAIN SHOWERS ARE FORECAST TO PRODUCE A TENTH TO A HALF INCH BASIN AVERAGE OF RAINFALL DURING THE NEXT 3 TO 4 DAYS. THE NEXT CHANCE FOR APPRECIABLE RAINFALL ARRIVES DURING THE SECOND HALF OF THE WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...BGM NEAR TERM...BGM SHORT TERM...BGM LONG TERM...FRUGIS AVIATION...FRUGIS FIRE WEATHER...BGM HYDROLOGY...BGM
AREA FORECAST DISCUSSION
NWS DES MOINES IA
813 AM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 812 AM CDT SUN MAY 4 2014 UPDATED ZONES TO INCLUDE SHOWER/SLEET MIX ACROSS THE FAR NORTH NEAR HANCOCK/WORTH/CERRO GORDO COUNTIES. RECENT REPORT OF MIXTURE IN THE PAST 30 MINUTES./REV && .SHORT TERM /TODAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST CONCERN FOR TODAY WILL BE PRECIPITATION CHANCES IN THE MORNING HOURS. CURRENTLY...PRECIPITATION IS BEGINNING TO FILL IN AND EXPAND IN CENTRAL SD/NORTHERN NE AS SHORTWAVE PUSHES SE. HIGH RES MODELS HAVE THE BEST HANDLE ON ONGOING PRECIPITATION...AND HAVE TRENDED TOWARDS HRRR AND CONSSHORT AND HAVE EXTENDED POPS FURTHER SOUTH AND WEST. HOWEVER...HAVE NOT BEEN AS AGGRESSIVE AS MODELS INDICATE GIVEN LARGE AMOUNT OF LOW LEVEL DRY AIR. SOUNDINGS STILL INDICATING MOISTURE SOMEWHAT LACKING IN CENTRAL CWA. THEREFORE...HAVE ALSO KEPT PRECIP MENTION SCATTERED/ISOLATED. SYSTEM WILL PUSH QUICKLY EAST/NORTHEAST WITH DRY CONDITIONS IN STORE FOR REMAINDER OF AFTERNOON AS WEAK RIDGE PUSHES IN. HAVE INCREASED TEMPERATURES WITH DECENT WAA...ESPECIALLY IN THE SOUTH. .LONG TERM /TONIGHT THROUGH FRIDAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 LONG TERM FORECAST WILL BE DOMINATED BY LARGE WESTERN TROF THAT EVENTUALLY TRACKS EASTWARD THROUGH THE REGION BY LATE IN THE WORK WEEK. PRIOR TO THE ARRIVAL HOWEVER...THE WEATHER WILL BE RELATIVELY TRANQUIL FROM TONIGHT INTO TUESDAY. SURFACE BOUNDARY WILL SET UP ACROSS MISSOURI DURING THIS TIME WITH DRY EASTERLY LOW-LEVEL FLOW ACROSS IOWA. WILL SEE WARM ADVECTION GETTING PROGRESSIVELY STRONGER THROUGH MONDAY INTO TUESDAY WITH HIGHS BY TUESDAY AFTERNOON GETTING CLOSE TO NORMAL. FRONT WILL BEGIN TO LIFT NORTHWARD INTO THE STATE TUESDAY NIGHT INTO WEDNESDAY IN RESPONSE TO DEVELOPING SURFACE LOW ACROSS THE PLAINS. INCREASING THETA-E ADVECTION ON TUESDAY NIGHT SHOULD LEAD TO DEVELOPMENT OF SCATTERED CONVECTION IN NORTHERN IOWA LATE. THIS CONVECTION MAY LINGER INTO WEDNESDAY MORNING IN THE FAR NORTH AS THERMAL RIDGE BUILDS INTO THE STATE. BY WEDNESDAY AFTERNOON... HIGHS WELL INTO THE 80S ARE EXPECTED WITH DEEP MIXING AND STRONG SOUTHERLY FLOW INTO THE STATE. WHILE SOME CONVECTION WILL OCCUR ON WEDNESDAY NIGHT...IT IS LIKELY THE BULK OF ANY PRECIPITATION WILL BE NORTHWEST OF THE FORECAST AREA CLOSER TO THE SURFACE BOUNDARY. THIS BOUNDARY WILL SAG INTO STATE ON THURSDAY WITH CONVECTION LIKELY TO BECOME WIDESPREAD BY AFTERNOON IN MOST LOCATIONS. A FEW SEVERE STORMS WILL ALSO BE POSSIBLE WITH THIS CONVECTION. THE STORMS ARE EXPECTED TO CONTINUE INTO THURSDAY NIGHT BUT WITH PROGRESSION TO THE EAST AS THE BOUNDARY SLIDES THROUGH THE STATE. SOME LINGERING PCPN IS FORECAST ON FRIDAY BEFORE ENDING WITH DRIER CONDITIONS INTO FRIDAY NIGHT. && .AVIATION...04/12Z ISSUED AT 627 AM CDT SUN MAY 4 2014 BRIEF CHANCE FOR SHRA TO AFFECT NORTHERN SITES...KMCW/KALO AT BEGINNING OF PERIOD. HOWEVER...CONDITIONS WILL REMAIN VFR THROUGH PERIOD. WINDS WILL BECOME MORE EASTERLY THROUGH DAY...WITH GUSTS POSSIBLE IN AFTERNOON. WINDS WILL DIMINISH AFTER 00Z. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...REV SHORT TERM...AWB LONG TERM...COGIL AVIATION...AWB
AREA FORECAST DISCUSSION
NWS DES MOINES IA
629 AM CDT SUN MAY 4 2014 .SHORT TERM /TODAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST CONCERN FOR TODAY WILL BE PRECIPITATION CHANCES IN THE MORNING HOURS. CURRENTLY...PRECIPITATION IS BEGINNING TO FILL IN AND EXPAND IN CENTRAL SD/NORTHERN NE AS SHORTWAVE PUSHES SE. HIGH RES MODELS HAVE THE BEST HANDLE ON ONGOING PRECIPITATION...AND HAVE TRENDED TOWARDS HRRR AND CONSSHORT AND HAVE EXTENDED POPS FURTHER SOUTH AND WEST. HOWEVER...HAVE NOT BEEN AS AGGRESSIVE AS MODELS INDICATE GIVEN LARGE AMOUNT OF LOW LEVEL DRY AIR. SOUNDINGS STILL INDICATING MOISTURE SOMEWHAT LACKING IN CENTRAL CWA. THEREFORE...HAVE ALSO KEPT PRECIP MENTION SCATTERED/ISOLATED. SYSTEM WILL PUSH QUICKLY EAST/NORTHEAST WITH DRY CONDITIONS IN STORE FOR REMAINDER OF AFTERNOON AS WEAK RIDGE PUSHES IN. HAVE INCREASED TEMPERATURES WITH DECENT WAA...ESPECIALLY IN THE SOUTH. .LONG TERM /TONIGHT THROUGH FRIDAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 LONG TERM FORECAST WILL BE DOMINATED BY LARGE WESTERN TROF THAT EVENTUALLY TRACKS EASTWARD THROUGH THE REGION BY LATE IN THE WORK WEEK. PRIOR TO THE ARRIVAL HOWEVER...THE WEATHER WILL BE RELATIVELY TRANQUIL FROM TONIGHT INTO TUESDAY. SURFACE BOUNDARY WILL SET UP ACROSS MISSOURI DURING THIS TIME WITH DRY EASTERLY LOW-LEVEL FLOW ACROSS IOWA. WILL SEE WARM ADVECTION GETTING PROGRESSIVELY STRONGER THROUGH MONDAY INTO TUESDAY WITH HIGHS BY TUESDAY AFTERNOON GETTING CLOSE TO NORMAL. FRONT WILL BEGIN TO LIFT NORTHWARD INTO THE STATE TUESDAY NIGHT INTO WEDNESDAY IN RESPONSE TO DEVELOPING SURFACE LOW ACROSS THE PLAINS. INCREASING THETA-E ADVECTION ON TUESDAY NIGHT SHOULD LEAD TO DEVELOPMENT OF SCATTERED CONVECTION IN NORTHERN IOWA LATE. THIS CONVECTION MAY LINGER INTO WEDNESDAY MORNING IN THE FAR NORTH AS THERMAL RIDGE BUILDS INTO THE STATE. BY WEDNESDAY AFTERNOON... HIGHS WELL INTO THE 80S ARE EXPECTED WITH DEEP MIXING AND STRONG SOUTHERLY FLOW INTO THE STATE. WHILE SOME CONVECTION WILL OCCUR ON WEDNESDAY NIGHT...IT IS LIKELY THE BULK OF ANY PRECIPITATION WILL BE NORTHWEST OF THE FORECAST AREA CLOSER TO THE SURFACE BOUNDARY. THIS BOUNDARY WILL SAG INTO STATE ON THURSDAY WITH CONVECTION LIKELY TO BECOME WIDESPREAD BY AFTERNOON IN MOST LOCATIONS. A FEW SEVERE STORMS WILL ALSO BE POSSIBLE WITH THIS CONVECTION. THE STORMS ARE EXPECTED TO CONTINUE INTO THURSDAY NIGHT BUT WITH PROGRESSION TO THE EAST AS THE BOUNDARY SLIDES THROUGH THE STATE. SOME LINGERING PCPN IS FORECAST ON FRIDAY BEFORE ENDING WITH DRIER CONDITIONS INTO FRIDAY NIGHT. && .AVIATION...04/12Z ISSUED AT 627 AM CDT SUN MAY 4 2014 BRIEF CHANCE FOR SHRA TO AFFECT NORTHERN SITES...KMCW/KALO AT BEGINNING OF PERIOD. HOWEVER...CONDITIONS WILL REMAIN VFR THROUGH PERIOD. WINDS WILL BECOME MORE EASTERLY THROUGH DAY...WITH GUSTS POSSIBLE IN AFTERNOON. WINDS WILL DIMINISH AFTER 00Z. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AWB LONG TERM...COGIL AVIATION...AWB
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
625 AM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 AS ADVERTISED BY THE NAM...STRONG MIDLEVEL FRONTOGENESIS HAS SPAWNED AN AREA OF SHOWERS AND THUNDERSTORMS ACROSS SD THIS MORNING. THE RAP SHOWS THIS FORCING MECHANISM MOVING QUICKLY EAST AWAY FROM THE FCST AREA BY 12Z THIS MORNING AND THIS IS CONSISTENT WITH THE LATEST RADAR TRENDS. THE RAP AND NAM GENERATE A FEW HUNDRED JOULES OF ELEVATED INSTABILITY THIS AFTN ACROSS PINE RIDGE SUGGESTING THE POTENTIAL FOR ISOLATED TSTM DEVELOPMENT. THE FORECAST IS DRY AS NEITHER MODEL IS GENERATING AND QPF IN THAT AREA. THE TEMPERATURE FORECAST TODAY HAS HIGHS RANGING FROM THE 60S NORTH TO UPPER 80S IN THE FAR SOUTHWEST. THE CANADIAN HIGH PRESSURE SYSTEM WILL CONTINUE TO RIDGE THRU MUCH OF THE FCST AREA TODAY SUPPORTING THIS TEMPERATURE FORECAST WHICH IS CONSISTENT WITH THE 07Z RUN OF THE RAP. ALL MODELS EXCEPT THE GEM SUGGEST THE POTENTIAL FOR STRATUS DEVELOPMENT TONIGHT BUT THE NAM AND ECM ONLY SHOW 85 PERCENT RH IN THE 500M AGL LEVEL VS THE GFS AROUND 98 PERCENT. THE BEST APPROACH AT THIS TIME WOULD BE TO WAIT FOR LATER MODEL DATA. A SMALL PATCH OF STRATUS HAS WORKED INTO PINE RIDGE THIS MORNING WHICH SHOULD BURN OFF BY NOON TIME ACCORDING TO THE RAP MODEL. LOWS TONIGHT FALL INTO THE 40S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MONDAY BEGINS WITH A BROAD RIDGE ACROSS MOST OF THE CONUS...WITH A TROUGH DIGGING INTO THE PAC NW AND ONE OFF THE NEW ENGLAND COAST. AT THE SFC A LEE SIDE TROUGH MEANDERS ACROSS THE FRONT RANGE FROM A LOW IN S CENTRAL CANADA TO A LOW IN KANSAS. DURING THE AFTERNOON SUNNY SKIES WILL MIX MID AND UPPER TEENS 850 MB TEMPS AND HIGHS IN THE 70S AND LOWER 80S. OVERNIGHT AN UPPER LEVEL DISTURBANCE WILL RIDE THE RIDGE ACROSS THE DAKOTAS. THIS WILL COMBINE WITH A LL JET TO PRODUCE SOME SHOWERS AND A FEW THUNDERSTORMS. MAJORITY OF THE ACTIVITY TO THE NORTH...HOWEVER THE NAM AND THE GFS SUPPORT SOME BUILDING SOUTH WHERE THERE IS SLIGHTLY BETTER MOISTURE. THE MOISTURE IS ONLY SLIGHTLY BETTER AND HAVE CONCERNS THE ACTIVITY WILL NOT DEVELOP THIS FAR SOUTH...AWAY FROM THE MAIN DISTURBANCE. MILD LOWS EXPECTED IN THE UPPER 40S TO AROUND 50. TUESDAY THE UPPER LEVEL TROUGH DIGS TOWARDS THE DESERT SOUTHWEST WITH THE RIDGE TO AMPLIFY OVER THE MISS RVR VALLEY. THIS WILL BEGIN THE TRANSITION TO MORE SW FLOW OVER THE HIGH PLAINS. TUESDAY STILL LOOKS DRY...THEN ANOTHER DISTURBANCE TO PUSH ACROSS THE AREA TUESDAY EVENING. MODELS INITIATE ACTIVITY TO THE WEST...WHICH SHOULD THEN PUSH NE ACROSS THE AREA. DRY AIR WILL BE TOUGH TO OVERCOME...ESPECIALLY IN THE SW...SO POPS CONFINED TO THE NW ZONES TUESDAY NIGHT. BY WEDNESDAY AND THURSDAY THE UPPER LEVEL TROUGH WILL BE CROSSING THE CENTRAL ROCKIES WHILE A COLD FRONT DRIFTS IN FROM THE NW. MEANWHILE SFC LOW STRENGTHEN OVER E CENTRAL COLORADO. THE LOW WILL THEN LIFT NE ACROSS NEB. TIMING STILL OFF A LITTLE BETWEEN THE MODELS...AND THE SLOWER GFS AND GEM HAVE A MORE PRONOUNCED DRY SLOT INTO SW AND S CENTRAL NEB. ANOTHER CONCERN IS THURSDAY NIGHT AS THE SYSTEM PUSHES EAST. THE EC DRAWS DOWN SOME COOLER AIR INTO FAR NW NEB...COLD ENOUGH FOR POSSIBLY A MIX. CURRENT THOUGH IS THE TEMPS TO NOT FALL FAST ENOUGH INTO THE MID 30S FOR ANY MIX AT THIS POINT AND NO MENTION OF SNOW. THE CLOUDS AND COOLER AIR BEHIND THE FRONT WILL RESULT IN 60S AND 70S ON WED AND 50S AND 60S FOR THURS. BY FRIDAY THE SYSTEM IS EAST WITH SLIGHT RIDGING OVER THE WEST. 850 MB TEMPS SLOWLY REBOUND AND A WARM UP IS EXPECTED. AFTER 60S ON FRIDAY...MORE 70S ARE FORECAST FOR SATURDAY. A LOW WILL PUSH ACROSS THE DAKOTAS IN THE ZONAL TO NW WEST FLOW. MOISTURE IS LIMITED TO BASICALLY THE PACIFIC AND WILL KEEP FORECAST DRY FOR NOW. WILL MONITOR AS WE MAY NEED TO ADD SOME ISOLATED SPRINKLES OR LIGHT SHOWERS IN THE COMING DAYS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 625 AM CDT SUN MAY 4 2014 VFR IS EXPECTED TODAY AND TONIGHT. SOME MODELS ARE SUGGESTING THE POTENTIAL FOR MVFR CIGS IN STRATUS TONIGHT BUT THIS HAS BEEN SET ASIDE FOR THE TIME BEING. ONCE THE MODELS COME INTO REASONABLY SOLID AGREEMENT A FORECAST CAN BE MADE. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1004 AM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 1002 AM CDT SUN MAY 4 2014 LATEST RUC AND NAM FOCUSING ON A VORT MAX MOVING ACROSS MAINLY THE NORTHERN HALF OF THE CWA THIS EVENING AND TONIGHT...WITH BEST CHANCES FOR PRECIP MAINLY NORTH OF THE I 94 CORRIDOR. WILL USE NAM GUIDANCE THROUGH ABOUT 09Z AND THEN NAM GUIDANCE THROUGH 12Z. SHOULD SEE MOST ACTIVITY ENDING BY MID MORNING MONDAY. CURRENT RADAR IS BEGINNING TO SHOW ECHOES ACROSS CENTRAL NORTH DAKOTA WITH MINIMAL GROUND TRUTH...MAINLY MID LEVEL DECK. THE NAM HAS DRIED THAT OUT IN THE EVENING HOURS...SO WILL NEED TO MONITOR OVER NEXT COUPLE OF HOURS AND SEE HOW THINGS EVOLVE AS THESE INITIAL (WEAK) ECHOES DRIFT EAST...AND WILL SPEED THINGS UP AS NECESSARY WITH 18Z UPDATE UPDATE ISSUED AT 709 AM CDT SUN MAY 4 2014 BAND OF LIGHT RAIN SHOWERS REMAINING JUST SOUTH OF THE AREA AND MOVING INTO SW MN ATTM. OTHERWISE EXTENSIVE MID AND HIGH LEVEL MOISTURE MOVING INTO ERN ND SO UPPED SKY COVER SOME FOR TODAY. OTHERWISE NO CHANGES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 347 AM CDT SUN MAY 4 2014 BAND OF SHOWERS FROM DICKINSON ND AREA TO SOUTH OF BISMARCK TO ABERDEEN SD MOVING SOUTHEAST. LOOKS LIKE THIS BAND WILL STAY JUST SOUTH OF OUR FCST AREA. THIS ASSOCIATED WITH MID LEVEL FRONTOGENESIS. FARTHER SOUTH ACTUALLY A FEW HIGH BASED THUNDERSTORMS IN CENTRAL SD EAST OF PIERRE TOWARD HURON. THIS FORCING WILL EXIT SOUTHEAST THIS MORNING. OTHERWISE...SKIES CLEAR NE 1/2 OF FCST AREA ALONG AND NORTH OF CANDO-GRAND FORKS-PARK RAPIDS LINE. EXPECT GENERAL INCREASE IN HIGH CLOUDS TO SPREAD EAST THIS MORNING WITH THICKER CLOUD COVER SPREADING OVER MUCH OF THE AREA THIS AFTN/EVE AHEAD OF UPSTREAM SHORTWAVE IN MONTANA. THE UPSTREAM SHORT WAVE WILL MOVE INTO WRN ND TODAY AND THRU ERN ND/NW MN TONIGHT. WEAK FRONTOGENTICAL FORCING BUT SOME MID LEVEL WARM ADVECTION ASSOCIATED WITH THIS WAVE AND WITH SHOWERS ON RADARS TO OUR WEST WENT ALONG WITH WFO BIS AND INCREASED POPS IN NE ND INTO THE CNTRL RRV TONIGHT. MONDAY WILL SEE ANY PRECIP EXIT THE MN FCST AREA EARLY...BUT CONSIDERABLE MID AND HIGH LEVEL MOISTURE REMAINING. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN MAY 4 2014 WILL MAINTAIN A LOW POP IN FAR WRN FCST AREA MON NIGHT AS MOISTURE RETURNS NORTHEAST AHEAD OF NEXT LARGER SYSTEM. THEN INCREASING PRECIP CHANCES TO SPREAD INTO THE AREA DAYTIME TUESDAY AS 850-700 MB WARM/MOIST ADVECTION RETURNS AHEAD OF LARGE SCALE 500 MB TROUGH THAT WILL BE MOVING INTO THE ROCKIES. FOR WEDNESDAY THROUGH SUNDAY...CONSISTENCY THIS PERIOD CONTINUES WITH LATEST SUITE OF MODELS AS IT RELATES TO THE LARGE SCALE. QUESTIONS ABOUND REGARDING THE AMOUNT OF QPF THAT WILL DEVELOP OVER THE NORTHWEST HALF OF THE CWFA BEHIND INVERTED TROUGH WEDNESDAY. CONVECTION FORECAST SOUTH AND EAST OF OUR CWFA MAY BLOCK THE DEEPER MOISTURE REDUCING OVERALL QPF. ECMWF AND NAM12/DGEX SUGGEST SAID CONVECTION BRUSHING THE SOUTHEAST PART OF THE FA WEDNESDAY. GFS IS FARTHEST NORTH AND WEST WITH INSTABILITY AFT 00Z THU. GEM-NH...ECMWF AND DGEX FARTHER SOUTHEAST SUGGEST TSRA RISK FOR OUR AREA IS PRETTY LOW. BEST TIMING WOULD BE IN THE 12Z WED - 06Z THU AND SHOULD BE ISOLD AT BEST. FOR THURSDAY THE MODELS ARE IN FAIR AGREEMENT WITH SURFACE LOW OVER CENTRAL PLAINS AND TROUGH APPROX FSD-DLH LINE. ISENTROPIC UPGLIDE... 850-500 DIV Q...700 FRONTOGEN AND COUPLED JET SUPPLYING THE LIFT FOR -RASH/-RA OVER MUCH OF THE CWFA. QUESTION AGAIN IS HOW MUCH PLAINS CONVECTION INTERFERES WITH MOISTURE TRANSPORT AND RESULTANT QPF. ON FRIDAY LOW WRAPS UP INTO WESTERN GREAT LAKES/SOUTHERN ONTARIO TAKING MOISTURE AND LIFT WITH IT. COLDER AIR ALOFT MAY YIELD TO SOME -RASH LATE FRIDAY. THIS DEPARTING SYSTEM QUICKLY FOLLOWED BY WAVES ROTATING AROUND BASE OF UPPER LOW OVER MANITOBA/SASKATCHEWAN BORDER REGION. THUS UNSETTLED...SHOWERY WEATHER IS SUGGESTED INTO THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 709 AM CDT SUN MAY 4 2014 VFR TODAY AND TONIGHT. LOOK FOR INCREASING HIGH AND MID LEVEL MOISTURE TODAY WITH MID LEVEL MOISTURE OVER THE AREA TONIGHT ALONG WITH SOME RAIN SHOWERS...ESP NR HIGHWAY TWO CORRIDOR. WINDS LIGHT THIS MORNING TURNING MORE EAST-NORTHEAST AT 10 KTS OR LESS THIS AFTN-TONIGHT. && .HYDROLOGY... ISSUED AT 1150 PM CDT SAT MAY 3 2014 OVER THE NEXT 3 DAYS LESS THAN ONE QUARTER OF AN INCH OF RAIN IS EXPECTED. AMOUNTS THAT LIGHT WILL HAVE NO IMPACT TO CURRENT RIVER FORECASTS. FARGO IS THE ONLY FORECAST POINT CURRENT ABOVE MODERATE FLOOD STAGE AND IS FALLING...PROBABLY GOING BELOW MODERATE LEVELS LATE TODAY OR TONIGHT. HALSTAD...EAST GRAND FORKS AND OSLO ARE AT OR PAST THEIR BROAD CRESTS AND SHOULD FALL VERY SLOWLY THE NEXT FEW DAYS. DOWNSTREAM AT DRAYTON AND PEMBINA BOTH ARE JUST ABOVE FIS AND SLOW RISES ARE INDICATED THE NEXT FEW DAYS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...SPEICHER SHORT TERM...RIDDLE LONG TERM...EWENS/RIDDLE AVIATION...RIDDLE HYDROLOGY...EWENS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
952 AM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 951 AM CDT SUN MAY 4 2014 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE FOR THE REMAINDER OF THE MORNING AND EARLY AFTERNOON. THE BIGGEST QUESTION IS SNOWFALL POTENTIAL THIS EVENING AND TONIGHT ALONG AND NORTH OF US HIGHWAY 2...WHERE THE INCOMING 12 UTC DETERMINISTIC GUIDANCE CONTINUES THE TREND OF THE 06 UTC SUITE OF THE POTENTIAL FOR ONE TO THREE INCHES OF SNOW. SURFACE TEMPERATURES WILL BE CRITICAL FOR PRECIPITATION TYPE...AND AFTERNOON WARMING WILL HAVE TO BE CLOSELY MONITORED TO DETERMINE THE TIMING OF CHANGE OVER TO SNOW. UPDATE ISSUED AT 612 AM CDT SUN MAY 4 2014 EARLY MORNING UPDATE FOR MINOR CHANGES TO TEMPERATURE TRENDS AND POPS. A NARROW BAND OF LIGHT SNOW AND MIXED PRECIPITATION CONTINUES FROM THE DICKINSON AREA...THROUGH MORTON COUNTY...INTO THE JAMES RIVER VALLEY. ANY ACCUMULATIONS OF GRASSY AREAS SHOULD MELT QUICKLY TODAY. ADDITIONAL PRECIPITATION EXPECTED TO MOVE INTO NORTHWEST ND AROUND MIDDAY AND CONTINUE PUSHING EAST THROUGH THE AFTERNOON. TEMPS EXPECTED TO BE WARM ENOUGH FOR ALL RAIN THERE...ALTHOUGH THAT WOULD NOT BE THE CASE GIVEN THE 06Z NAM WHICH INDICATES MORE QPF THIS MORNING. WILL PASS CONCERNS ALONG TO THE DAY SHIFT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OFF THE WASHINGTON COAST WITH ADDITIONAL SHORTWAVES FARTHER UPSTREAM YET TO ROUND THE BASE OF THE TROUGH. A COUPLE OF SHORTWAVES WILL PEEL OFF THE MAIN UPPER LOW/TROUGH AND EJECT INTO NORTH DAKOTA THROUGH THE SHORT TERM PERIOD. FOR THE NEAR TERM/EARLY THIS MORNING...MONITORING THE NARROW BANDS OF PRECIPITATION ON THE BOWMAN AND BISMARCK RADARS. NOTHING SIGNIFICANT ON AMOUNTS VIA SURFACE REPORTS OR WEB CAMS...BUT AMOUNTS MAY BE FALLING IN BETWEEN ABOVE MENTIONED DATA POINTS. LATEST HRRR AND RAP BOTH LIFT THE NARROW BAND OF PRECIPITATION WEAKLY TO THE NORTHEAST THROUGH THE MORNING. THE ECMWF KEEPS THE BRUNT OF THE PRECIPITATION AMOUNTS IN THE FAR SOUTH...WHILE THE NAM/GFS SHOW A NARROW SWATH OF DECENT QPF WEST INTO SOUTH CENTRAL. WILL CONTINUE WITH A CHANCE TO LIKELY POPS MENTIONING SNOW/RAIN THROUGH MID MORNING BEFORE TRENDING DOWNWARD. LATER TODAY...CONSENSUS IS FOR THE NEXT SHORTWAVE TO MOVE FROM THE CENTRAL IDAHO PANHANDLE INTO NORTHERN NORTH DAKOTA BETWEEN 18Z SUNDAY AND 06Z MONDAY. THIS WILL RESULT IN CATEGORICAL POPS FOR THE NORTH DURING THIS TIME AND A CHANCE OF SHOWERS ELSEWHERE. TOWARD 00Z MONDAY...WEAK INSTABILITY PUSHES CLOSE TO OUR SOUTHWEST BORDER AND HAVE MAINTAINED A SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH AT LEAST MID WEEK. MEDIUM RANGE MODELS ARE STARTING TO COAL ESE AROUND A SIMILAR PROGRESSION OF A LARGE WESTERN CONUS TROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE MONDAY NIGHT...WITH PERIODS OF SHOWERS AND ISOLATED CONVECTION CONTINUING THROUGH WEDNESDAY NIGHT BEFORE TAPERING OFF THURSDAY. CONSENSUS QPF AMONGST THE GFS/ECMWF/GEM NOW SUPPORTS WIDESPREAD TOTAL RAINFALL OF 0.33 TO 1 INCH...LESS BULLISH THAN PREVIOUS DAYS. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. ANOTHER STORM SYSTEM COULD BRING ADDITIONAL SHOWERS TO THE FORECAST AREA ON SATURDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 951 AM CDT SUN MAY 4 2014 VFR CONDITIONS THIS MORNING AND AFTERNOON WILL TREND TOWARDS MVFR/IFR AT KISN AND KMOT LATE THIS AFTERNOON AND INTO THE EVENING IN STRATUS AND RAIN POSSIBLY MIXING WITH SNOW AFTER SUNSET. ELSEWHERE...VFR CONDITIONS ARE FORECAST FOR THE 12 UTC TAF CYCLE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
648 AM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 612 AM CDT SUN MAY 4 2014 EARLY MORNING UPDATE FOR MINOR CHANGES TO TEMPERATURE TRENDS AND POPS. A NARROW BAND OF LIGHT SNOW AND MIXED PRECIPITATION CONTINUES FROM THE DICKINSON AREA...THROUGH MORTON COUNTY...INTO THE JAMES RIVER VALLEY. ANY ACCUMULATIONS OF GRASSY AREAS SHOULD MELT QUICKLY TODAY. ADDITIONAL PRECIPITATION EXPECTED TO MOVE INTO NORTHWEST ND AROUND MIDDAY AND CONTINUE PUSHING EAST THROUGH THE AFTERNOON. TEMPS EXPECTED TO BE WARM ENOUGH FOR ALL RAIN THERE...ALTHOUGH THAT WOULD NOT BE THE CASE GIVEN THE 06Z NAM WHICH INDICATES MORE QPF THIS MORNING. WILL PASS CONCERNS ALONG TO THE DAY SHIFT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OFF THE WASHINGTON COAST WITH ADDITIONAL SHORTWAVES FARTHER UPSTREAM YET TO ROUND THE BASE OF THE TROUGH. A COUPLE OF SHORTWAVES WILL PEEL OFF THE MAIN UPPER LOW/TROUGH AND EJECT INTO NORTH DAKOTA THROUGH THE SHORT TERM PERIOD. FOR THE NEAR TERM/EARLY THIS MORNING...MONITORING THE NARROW BANDS OF PRECIPITATION ON THE BOWMAN AND BISMARCK RADARS. NOTHING SIGNIFICANT ON AMOUNTS VIA SURFACE REPORTS OR WEB CAMS...BUT AMOUNTS MAY BE FALLING IN BETWEEN ABOVE MENTIONED DATA POINTS. LATEST HRRR AND RAP BOTH LIFT THE NARROW BAND OF PRECIPITATION WEAKLY TO THE NORTHEAST THROUGH THE MORNING. THE ECMWF KEEPS THE BRUNT OF THE PRECIPITATION AMOUNTS IN THE FAR SOUTH...WHILE THE NAM/GFS SHOW A NARROW SWATH OF DECENT QPF WEST INTO SOUTH CENTRAL. WILL CONTINUE WITH A CHANCE TO LIKELY POPS MENTIONING SNOW/RAIN THROUGH MID MORNING BEFORE TRENDING DOWNWARD. LATER TODAY...CONSENSUS IS FOR THE NEXT SHORTWAVE TO MOVE FROM THE CENTRAL IDAHO PANHANDLE INTO NORTHERN NORTH DAKOTA BETWEEN 18Z SUNDAY AND 06Z MONDAY. THIS WILL RESULT IN CATEGORICAL POPS FOR THE NORTH DURING THIS TIME AND A CHANCE OF SHOWERS ELSEWHERE. TOWARD 00Z MONDAY...WEAK INSTABILITY PUSHES CLOSE TO OUR SOUTHWEST BORDER AND HAVE MAINTAINED A SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH AT LEAST MID WEEK. MEDIUM RANGE MODELS ARE STARTING TO COAL ESE AROUND A SIMILAR PROGRESSION OF A LARGE WESTERN CONUS TROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE MONDAY NIGHT...WITH PERIODS OF SHOWERS AND ISOLATED CONVECTION CONTINUING THROUGH WEDNESDAY NIGHT BEFORE TAPERING OFF THURSDAY. CONSENSUS QPF AMONGST THE GFS/ECMWF/GEM NOW SUPPORTS WIDESPREAD TOTAL RAINFALL OF 0.33 TO 1 INCH...LESS BULLISH THAN PREVIOUS DAYS. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. ANOTHER STORM SYSTEM COULD BRING ADDITIONAL SHOWERS TO THE FORECAST AREA ON SATURDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 640 AM CDT SUN MAY 4 2014 AN AREA OF MVFR CIGS IN -SN WILL CONTINUE TO SLIDE ACROSS KDIK AND INTO KBIS THROUGH 15Z SUNDAY. OTHERWISE ATTENTION WILL TURN TOWARD KISN AND KMOT WHERE AN AREA OF PRECIPITATION WILL EXPAND OVER EASTERN MONTANA INTO NORTHERN NORTH DAKOTA TODAY INTO TONIGHT. EXPECT MVFR CIGS AT KISN/KMOT WITH -SN IN THE MORNING MIXING WITH AND CHANGING TO -RA BY THE AFTERNOON. KJMS WILL REMAIN DRY WITH VFR CIGS THROUGH THE TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE/LONG TERM...RP KINNEY SHORT TERM/AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
749 AM EDT SUN MAY 4 2014 .SYNOPSIS... A WEAK TROF WILL MOVE ACROSS THE AREA TODAY. HIGH PRESSURE WILL BUILD SOUTHEAST INTO THE REGION TONIGHT AND WILL REMAIN NEARLY STATIONARY OVER THE LAKES THROUGH TUESDAY AND BEGIN TO MOVE EAST OF THE REGION TUESDAY NIGHT. A WARM FRONT WILL LIFT NORTH ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED TO ADJUST THE POPS FOR TODAY MAINLY OVER THE EASTERN PORTION OF THE FORECAST AREA. THE HRRR MODEL SEEMS TO HAVE A GOOD HANDLE ON THE WEATHER. THIS FIRST WAVE OF SHOWERS IS AFFECT NE OH AND NW PA AND THEN ANOTHER WAVE OF SHOWERS AROUND NOON WILL MAINLY AFFECT EXTREME NE OH AND NW PA. NW OH WILL HAVE A MIX OF CLOUDS AND SUNSHINE. PREVIOUS DISCUSSION... NOT A CLEAR CUT FORECAST FOR TODAY...ESPECIALLY OVER THE EASTERN PORTION OF THE FORECAST AREA. SOME LIGHT SHOWERS ARE STILL MOVING ACROSS THE AREA...THEY ARE ASSOCIATED WITH AN UPPER JET THAT IS STILL ACROSS THE AREA AND A WEAK SURFACE TROF THAT WILL MOVE THROUGH THIS MORNING. LATE THIS MORNING AND AFTERNOON IS TOUGH. AN UPPER LOW OVER THE NORTHERN LAKES EARLY THIS MORNING WILL MOVE TOWARD WESTERN NEW YORK STATE FOR THE AFTERNOON...SO WENT WITH LIKELY POPS FOR NW PA. THE QUESTION IS HOW FAR WEST AND SOUTH SHOULD THE CHANCE BE. PLENTY OF DRY AIR WILL BE MOVING IN...SO TRIED TO LIMIT THE SHOWERS TO NE OH. THE HRRR MODEL HAS SOME SHOWERS NEAR THE SOUTHERN PORTION OF THE FORECAST AREA THIS AFTERNOON AND THIS IS ASSOCIATED WITH THE FRONT THAT MOVED ACROSS THE AREA SATURDAY NIGHT AND WAS NEAR THE OHIO RIVER THIS MORNING. WITH COLDER AIR ALOFT AND SOME CLOUDS WENT COOLER THAN YESTERDAY. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... THE FORECAST IS STILL NOT CLEAR CUT. TONIGHT WILL BE DRY WITH LIGHT WINDS AND MOSTLY CLEAR SKIES TO START AS HIGH PRESSURE WILL BE OVER THE AREA. THE CLOUDS WILL BE ON THE INCREASE DURING THE OVERNIGHT AND THE QUESTION IS HOW FAR EAST WILL THEY GET AND THE IMPACT ON FROST AND FREEZE. AT THIS TIME WITH CONFIDENCE LOW WILL ONLY MENTION PATCHY FROST FOR EXTREME NE OH AND NW PA. THE NEXT SHIFT WILL HAVE TO WATCH THE SKY COVER. IF CLOUDS DON`T COME IN...SOME LOCATIONS MAY HAVE TEMPERATURES BELOW FREEZING...WHILE IF THIN CLOUDS COME IN THEY MAY LIMIT THE PROBLEM TO SOME FROST. WILL MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK. FOR MONDAY A CHANCE OF SHOWERS AS A SHORT WAVE MOVES THROUGH EVEN WITH HIGH PRESSURE AT THE SURFACE OVER NE OH AND NW PA. DRY MONDAY NIGHT THROUGH TUESDAY NIGHT AND THEN A CHANCE WEDNESDAY INTO WEDNESDAY NIGHT AS A WARM FRONT MOVES ACROSS THE AREA. LOWEST CONFIDENCE IS IN THE FORECAST FOR MONDAY BECAUSE OF HIGH PRESSURE AT THE SURFACE BUT A FAIR AMOUNT OF OMEGA. A WARM TREND STARTING MID WEEK. WITH SOME QUESTIONS ABOUT THE CHANCES OF RAIN...THIS COULD CAUSE PROBLEMS WITH THE TEMPERATURE FORECAST...USED A BLEND OF GUIDANCE. && .LONG TERM /THURSDAY THROUGH SATURDAY/... MODELS INDICATE THE WARM FRONT WILL BE NORTH OF THE AREA ON THURSDAY WITH BREEZY SOUTHWEST WINDS PUSHING TEMPERATURES TO NEAR 80 DEGREES. REMOVED CHANCES OF PRECIPITATION FROM THE FORECAST WITH THE RIDGE AXIS OVERHEAD AND A CAP IN PLACE. MODELS SHOW SOME MOISTURE NEAR 850MB SO KEPT THE FORECAST AS PARTLY SUNNY...BUT WONT BE SURPRISED IF WE REALLY END UP BEING MOSTLY SUNNY. LOW PRESSURE WILL TRACK FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST ON THURSDAY NIGHT. MOISTURE ADVECTION DOES NOT REALLY RAMP UP UNTIL FRIDAY SO ONLY INCLUDED A LOW CHANCE POP IN A FEW OF THE WESTERN COUNTIES ON THURSDAY NIGHT. MOISTURE WILL OVERSPREAD THE AREA IN ADVANCE OF THE FRONT ON FRIDAY/FRIDAY NIGHT AND RAISED POPS TO NEAR 50 PERCENT. CHANCES OF PRECIPITATION ON SATURDAY WILL DEPEND ON WHERE THE FRONT STALLS AND IF IT PUSHES SOUTH OF THE FORECAST AREA. ENOUGH UNCERTAINTY TO CONTINUE WITH A CHANCE OF SHOWERS/THUNDERSTORMS AT THIS POINT WITH BEST CHANCES ACROSS THE SOUTHERN COUNTIES. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... SCATTERED LIGHT SHOWERS WILL MOVE ACROSS EXTREME NE OHIO/NW PA THROUGH 21Z. CONDITIONS ARE EXPECTED TO REMAIN VFR UNLESS VISIBILITIES BRIEFLY DROP IN ANY MORE MODERATE SHOWERS. LIGHT SOUTHWEST WINDS WILL INCREASE WITH GUSTS TO 25 KNOTS AS THEY SHIFT TO WEST BETWEEN 14-16Z...THEN NORTHWEST BY 20Z. WINDS ARE EXPECTED TO DROP OFF TOWARDS 00Z AND BECOME LIGHT AND VARIABLE OVERNIGHT AS HIGH PRESSURE BUILDS SOUTHEAST OVER THE REGION. .OUTLOOK...NON VFR MAY OCCUR WEDNESDAY NIGHT AS A WARM FRONT LIFTS ACROSS THE REGION WITH SHOWERS. && .MARINE... WEST TO SOUTHWEST WINDS WILL START THE DAY ON LAKE ERIE. WINDS ARE LIGHT ON THE WEST HALF OF THE LAKE BUT HOLDING IN THE 10-20 KNOT RANGE ON THE EAST HALF OF THE LAKE. A COLD FRONT WILL PUSH SOUTH ACROSS THE LAKE TODAY BUT APPEARS WEAKER THAN PREVIOUSLY THOUGHT. WINDS WILL VEER TO WEST NORTHWEST WITH THE PASSAGE OF THE FRONT EARLY THIS AFTERNOON. WAVES WILL INCREASE AS THE FLOW BECOMES MORE ONSHORE ON THE EAST HALF OF THE LAKE...INCREASING TO 2 TO 5 FEET FOR A WINDOW LATE THIS AFTERNOON. WE ALREADY HAVE A SMALL CRAFT ADVISORY IN EFFECT. CONDITIONS MAY END UP BEING MARGINAL FOR THE SMALL CRAFT ADVISORY AND WE MAY BE ABLE TO CANCEL IT EARLY IF MODELS CONTINUE TO TREND LIGHTER WITH THE WINDS. CONDITIONS WILL IMPROVE QUICKLY TONIGHT AS HIGH PRESSURE BUILDS IN FROM THE WEST. WINDS WILL HAVE A EAST TO NORTHEAST DIRECTION THROUGH WEDNESDAY AS HIGH PRESSURE PASSES NORTH OF THE LAKE. A WARM FRONT WILL LIFT NORTH ACROSS THE LAKE ON WEDNESDAY NIGHT WITH A WARM AND STABLE SOUTHERLY FLOW EXPECTED BY THURSDAY. ACTIVE WEATHER TO FINISH THE WEEK WITH PERIODS OF SHOWERS AND THUNDERSTORMS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ146>149. && $$ SYNOPSIS...KIELTYKA NEAR TERM...KIELTYKA SHORT TERM...KIELTYKA LONG TERM...KEC AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
647 AM EDT SUN MAY 4 2014 .SYNOPSIS... A WEAK TROF WILL MOVE ACROSS THE AREA TODAY. HIGH PRESSURE WILL BUILD SOUTHEAST INTO THE REGION TONIGHT AND WILL REMAIN NEARLY STATIONARY OVER THE LAKES THROUGH TUESDAY AND BEGIN TO MOVE EAST OF THE REGION TUESDAY NIGHT. A WARM FRONT WILL LIFT NORTH ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED TO ADJUST THE POPS FOR TODAY MAINLY OVER THE EASTERN PORTION OF THE FORECAST AREA. THE HRRR MODEL SEEMS TO HAVE A GOOD HANDLE ON THE WEATHER. THIS FIRST WAVE OF SHOWERS IS AFFECT NE OH AND NW PA AND THEN ANOTHER WAVE OF SHOWERS AROUND NOON WILL MAINLY AFFECT EXTREME NE OH AND NW PA. NW OH WILL HAVE A MIX OF CLOUDS AND SUNSHINE. PREVIOUS DISCUSSION... NOT A CLEAR CUT FORECAST FOR TODAY...ESPECIALLY OVER THE EASTERN PORTION OF THE FORECAST AREA. SOME LIGHT SHOWERS ARE STILL MOVING ACROSS THE AREA...THEY ARE ASSOCIATED WITH AN UPPER JET THAT IS STILL ACROSS THE AREA AND A WEAK SURFACE TROF THAT WILL MOVE THROUGH THIS MORNING. LATE THIS MORNING AND AFTERNOON IS TOUGH. AN UPPER LOW OVER THE NORTHERN LAKES EARLY THIS MORNING WILL MOVE TOWARD WESTERN NEW YORK STATE FOR THE AFTERNOON...SO WENT WITH LIKELY POPS FOR NW PA. THE QUESTION IS HOW FAR WEST AND SOUTH SHOULD THE CHANCE BE. PLENTY OF DRY AIR WILL BE MOVING IN...SO TRIED TO LIMIT THE SHOWERS TO NE OH. THE HRRR MODEL HAS SOME SHOWERS NEAR THE SOUTHERN PORTION OF THE FORECAST AREA THIS AFTERNOON AND THIS IS ASSOCIATED WITH THE FRONT THAT MOVED ACROSS THE AREA SATURDAY NIGHT AND WAS NEAR THE OHIO RIVER THIS MORNING. WITH COLDER AIR ALOFT AND SOME CLOUDS WENT COOLER THAN YESTERDAY. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... THE FORECAST IS STILL NOT CLEAR CUT. TONIGHT WILL BE DRY WITH LIGHT WINDS AND MOSTLY CLEAR SKIES TO START AS HIGH PRESSURE WILL BE OVER THE AREA. THE CLOUDS WILL BE ON THE INCREASE DURING THE OVERNIGHT AND THE QUESTION IS HOW FAR EAST WILL THEY GET AND THE IMPACT ON FROST AND FREEZE. AT THIS TIME WITH CONFIDENCE LOW WILL ONLY MENTION PATCHY FROST FOR EXTREME NE OH AND NW PA. THE NEXT SHIFT WILL HAVE TO WATCH THE SKY COVER. IF CLOUDS DON`T COME IN...SOME LOCATIONS MAY HAVE TEMPERATURES BELOW FREEZING...WHILE IF THIN CLOUDS COME IN THEY MAY LIMIT THE PROBLEM TO SOME FROST. WILL MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK. FOR MONDAY A CHANCE OF SHOWERS AS A SHORT WAVE MOVES THROUGH EVEN WITH HIGH PRESSURE AT THE SURFACE OVER NE OH AND NW PA. DRY MONDAY NIGHT THROUGH TUESDAY NIGHT AND THEN A CHANCE WEDNESDAY INTO WEDNESDAY NIGHT AS A WARM FRONT MOVES ACROSS THE AREA. LOWEST CONFIDENCE IS IN THE FORECAST FOR MONDAY BECAUSE OF HIGH PRESSURE AT THE SURFACE BUT A FAIR AMOUNT OF OMEGA. A WARM TREND STARTING MID WEEK. WITH SOME QUESTIONS ABOUT THE CHANCES OF RAIN...THIS COULD CAUSE PROBLEMS WITH THE TEMPERATURE FORECAST...USED A BLEND OF GUIDANCE. && .LONG TERM /THURSDAY THROUGH SATURDAY/... MODELS INDICATE THE WARM FRONT WILL BE NORTH OF THE AREA ON THURSDAY WITH BREEZY SOUTHWEST WINDS PUSHING TEMPERATURES TO NEAR 80 DEGREES. REMOVED CHANCES OF PRECIPITATION FROM THE FORECAST WITH THE RIDGE AXIS OVERHEAD AND A CAP IN PLACE. MODELS SHOW SOME MOISTURE NEAR 850MB SO KEPT THE FORECAST AS PARTLY SUNNY...BUT WONT BE SURPRISED IF WE REALLY END UP BEING MOSTLY SUNNY. LOW PRESSURE WILL TRACK FROM THE CENTRAL PLAINS TO THE UPPER MIDWEST ON THURSDAY NIGHT. MOISTURE ADVECTION DOES NOT REALLY RAMP UP UNTIL FRIDAY SO ONLY INCLUDED A LOW CHANCE POP IN A FEW OF THE WESTERN COUNTIES ON THURSDAY NIGHT. MOISTURE WILL OVERSPREAD THE AREA IN ADVANCE OF THE FRONT ON FRIDAY/FRIDAY NIGHT AND RAISED POPS TO NEAR 50 PERCENT. CHANCES OF PRECIPITATION ON SATURDAY WILL DEPEND ON WHERE THE FRONT STALLS AND IF IT PUSHES SOUTH OF THE FORECAST AREA. ENOUGH UNCERTAINTY TO CONTINUE WITH A CHANCE OF SHOWERS/THUNDERSTORMS AT THIS POINT WITH BEST CHANCES ACROSS THE SOUTHERN COUNTIES. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... RADAR IMAGERY SHOWING SCATTERED LIGHT SHOWERS MOVING EAST ACROSS THE AREA EARLY THIS MORNING. CONDITIONS WILL GENERALLY BE VFR BUT VISIBILITIES COULD BRIEFLY DROP TO 5SM OR SO IN SOME OF THE MODERATE SHOWERS WITH BEST CHANCES AT CAK/YNG. LIGHT SOUTHWEST WINDS WILL BECOME GUSTY AS THEY SHIFT TO WEST NORTHWEST BETWEEN 14-16Z ON SUNDAY MORNING. ANOTHER PUSH OF MOISTURE WILL MOVE SE OUT OF CANADA TOWARDS ERI...POSSIBLY EXTENDING AS FAR WEST AS YNG...WITH LIGHT SHOWERS POSSIBLE AGAIN EARLY THIS AFTERNOON. WINDS ARE EXPECTED TO DROP OFF TOWARDS 00Z AND BECOME LIGHT AND VARIABLE MOST LOCATIONS OVERNIGHT. .OUTLOOK...NON VFR MAY OCCUR WEDNESDAY NIGHT AS A WARM FRONT LIFTS ACROSS THE REGION WITH SHOWERS. && .MARINE... WEST TO SOUTHWEST WINDS WILL START THE DAY ON LAKE ERIE. WINDS ARE LIGHT ON THE WEST HALF OF THE LAKE BUT HOLDING IN THE 10-20 KNOT RANGE ON THE EAST HALF OF THE LAKE. A COLD FRONT WILL PUSH SOUTH ACROSS THE LAKE TODAY BUT APPEARS WEAKER THAN PREVIOUSLY THOUGHT. WINDS WILL VEER TO WEST NORTHWEST WITH THE PASSAGE OF THE FRONT EARLY THIS AFTERNOON. WAVES WILL INCREASE AS THE FLOW BECOMES MORE ONSHORE ON THE EAST HALF OF THE LAKE...INCREASING TO 2 TO 5 FEET FOR A WINDOW LATE THIS AFTERNOON. WE ALREADY HAVE A SMALL CRAFT ADVISORY IN EFFECT. CONDITIONS MAY END UP BEING MARGINAL FOR THE SMALL CRAFT ADVISORY AND WE MAY BE ABLE TO CANCEL IT EARLY IF MODELS CONTINUE TO TREND LIGHTER WITH THE WINDS. CONDITIONS WILL IMPROVE QUICKLY TONIGHT AS HIGH PRESSURE BUILDS IN FROM THE WEST. WINDS WILL HAVE A EAST TO NORTHEAST DIRECTION THROUGH WEDNESDAY AS HIGH PRESSURE PASSES NORTH OF THE LAKE. A WARM FRONT WILL LIFT NORTH ACROSS THE LAKE ON WEDNESDAY NIGHT WITH A WARM AND STABLE SOUTHERLY FLOW EXPECTED BY THURSDAY. ACTIVE WEATHER TO FINISH THE WEEK WITH PERIODS OF SHOWERS AND THUNDERSTORMS. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ146>149. && $$ SYNOPSIS...KIELTYKA NEAR TERM...KIELTYKA SHORT TERM...KIELTYKA LONG TERM...KEC AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
954 AM CDT SUN MAY 4 2014 .UPDATE... ANOTHER QUICK UPDATE THIS MORNING TO COOL TEMPERATURES DOWN A FEW DEGREES MAINLY ALONG AND NORTH OF A LINE FROM TIMBER LAKE TO HAYTI...GIVEN EXPECTED DURATION OF CLOUDINESS AND ONGOING LOW LEVEL CAA ACROSS THE NORTHEASTERN HALF OF THE CWA ON EAST-SOUTHEASTERLY WINDS TODAY. DID NUDGE THE SOUTHWESTERN FORECAST ZONES UP A FEW DEGREES AS THAT AREA IS EXPECTED TO SEE SOME SUNSHINE BY EARLY THIS AFTERNOON. ALSO UPDATING THIS MORNING TO SCALE BACK POPS AND WIND DOWN THE POPS/WX MENTION SOONER...AND ELIMINATED THE LATE AFTERNOON POPS/WX MENTION ALTOGETHER...AS IT APPEARS THE NEXT AREA OF LOW PRESSURE MAY BE DELAYED A BIT AND PERHAPS MORE FOCUSED NORTH OF THIS CWA LATER TONIGHT. UPDATES ARE OUT. HYDROLOGY...WITH RECENT RAINFALL AND ONGOING UPSTREAM WATER RELEASES...THE JAMES RIVER IS JUST ABOUT TO HIT FLOOD STAGE...WHICH IS 13 FEET. THE LATEST RIVER FORECAST GUIDANCE CALLS FOR THE JAMES RIVER NEAR COLUMBIA TO RISE ABOVE FLOOD STAGE BY LATE THIS AFTERNOON...CRESTING AT APPX 13.5 FEET BY LATE MONDAY NIGHT. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH TUESDAY CURRENT RADAR IMAGERY SHOWING SCT SHOWERS AND EVEN A FEW THUNDERSHOWERS ACROSS CENTRAL SD AS MID LEVEL IMPULSE MOVES THROUGH. FURTHER EAST IN THE COLDER AIR...A MIX OF RAIN/SLEET/SNOW WAS OBSERVED AT ABR. HAVE ADJUSTED POP/WX GRIDS ACCORDINGLY AND WILL LIKELY NEED ADDITIONAL UPDATES IN A COUPLE HOURS. THE PAST SEVERAL RUNS OF THE HRRR AND THE 00Z EC HANDLED THIS SITUATION THE BEST...WITH THE 00Z GFS AND NAM WAY TOO FAR NORTH WITH THE PRECIPITATION. EXPECT THIS ACTIVITY TO CONTINUE SLIDING EAST THROUGH THE MORNING...MAINLY AFFECTING AREAS EAST OF THE MISSOURI RIVER. WITH COOL EASTERLY SFC FLOW DEVELOPING ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES...WILL BE A COOL DAY TODAY WITH HIGHS ONLY IN THE LOW TO MID 50S FOR MOST AREAS. WILL SEE ANOTHER WAVE OF ENERGY TACK EAST ACROSS THE AREA OVERNIGHT...AND A SLIGHTLY STRONGER ONE MONDAY NIGHT INTO TUESDAY. ALTHOUGH THE LATTER SYSTEM LOOKS TO BRING BEST PRECIP CHANCES TO THE WESTERN CWA AT THIS TIME. AS FAR AS INSTABILITY GOES...IT APPEARS WESTERN AND CENTRAL SD STAND THE BEST CHANCE TO SEE ANY CONVECTION WITH THESE COMING WAVES OF ENERGY. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY AN AREA OF LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS AT THE START OF THE PERIOD. THIS SYSTEM COMBINED WITH UPPER LEVEL SOUTHWEST FLOW WILL BRING INSTABILITY AND TSTORM CHANCES TO THE NORTHERN PLAINS THROUGH WED NIGHT. AN UPPER LOW WILL THEN TRANSITION OVER SD/NE BRINGING CONTINUED STORM CHANCES THURSDAY. BY FRIDAY SFC HIGH PRESSURE WILL BRIEFLY BUILD IN TO THE PLAINS BRINGING DRIER WEATHER. THEN A TROUGH MOVES THROUGH ON SAT EVEN AS ANOTHER LONG WAVE TROF TO THE WEST BEGINS TO EJECT UPPER LEVEL ENERGY INTO THE DAKOTAS. THIS MEANS TSTORMS WILL BE BACK IN THE FORECAST FOR THE WEEKEND. TEMPERATURES WILL BE NEAR OR BELOW NORMAL THROUGH THE PERIOD DUE TO RAIN AND CLOUD COVER. GOOD MIXING ON MOST DAYS EXCEPT FRIDAY WILL PUSH HIGHS INTO THE 60S. && .AVIATION... 12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS EXPECT VFR CEILINGS THROUGH TODAY AND TONIGHT AT ALL LOCATIONS. ALSO...EXPECT SOME LIGHT RAIN SHOWERS WITH A SHORT WAVE TROUGH MOVING THROUGH THE REGION. SHOWERS WILL AFFECT KATY AND KABR THIS MORNING BEFORE EXITING. BREEZY SOUTHEAST WINDS WILL DEVELOP THIS MORNING NEAR KPIR AND KMBG. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...DORN SHORT TERM...TMT LONG TERM...WISE AVIATION...WISE WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
738 AM CDT SUN MAY 4 2014 .UPDATE... TEMPERATURES ACROSS THE SOUTHEASTERN CWA ARE HOVERING RIGHT AROUND FREEZING THIS MORNING. WENT AHEAD AND ADDED IN SOME LIGHT FREEZING RAIN FOR CODINGTON..DEUEL AND HAMLIN COUNTIES THIS MORNING. NO ACCUMULATIONS ARE EXPECTED ON ROADS AND ANY PRECIP SHOULD CHANGE TO ALL RAIN BY MID MORNING. ALSO TRIMMED BACK ON POPS WEST RIVER AS ALL PRECIP APPEARS TO HAVE SHIFTED EAST ALREADY. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH TUESDAY CURRENT RADAR IMAGERY SHOWING SCT SHOWERS AND EVEN A FEW THUNDERSHOWERS ACROSS CENTRAL SD AS MID LEVEL IMPULSE MOVES THROUGH. FURTHER EAST IN THE COLDER AIR...A MIX OF RAIN/SLEET/SNOW WAS OBSERVED AT ABR. HAVE ADJUSTED POP/WX GRIDS ACCORDINGLY AND WILL LIKELY NEED ADDITIONAL UPDATES IN A COUPLE HOURS. THE PAST SEVERAL RUNS OF THE HRRR AND THE 00Z EC HANDLED THIS SITUATION THE BEST...WITH THE 00Z GFS AND NAM WAY TOO FAR NORTH WITH THE PRECIPITATION. EXPECT THIS ACTIVITY TO CONTINUE SLIDING EAST THROUGH THE MORNING...MAINLY AFFECTING AREAS EAST OF THE MISSOURI RIVER. WITH COOL EASTERLY SFC FLOW DEVELOPING ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES...WILL BE A COOL DAY TODAY WITH HIGHS ONLY IN THE LOW TO MID 50S FOR MOST AREAS. WILL SEE ANOTHER WAVE OF ENERGY TACK EAST ACROSS THE AREA OVERNIGHT...AND A SLIGHTLY STRONGER ONE MONDAY NIGHT INTO TUESDAY. ALTHOUGH THE LATTER SYSTEM LOOKS TO BRING BEST PRECIP CHANCES TO THE WESTERN CWA AT THIS TIME. AS FAR AS INSTABILITY GOES...IT APPEARS WESTERN AND CENTRAL SD STAND THE BEST CHANCE TO SEE ANY CONVECTION WITH THESE COMING WAVES OF ENERGY. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY AN AREA OF LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS AT THE START OF THE PERIOD. THIS SYSTEM COMBINED WITH UPPER LEVEL SOUTHWEST FLOW WILL BRING INSTABILITY AND TSTORM CHANCES TO THE NORTHERN PLAINS THROUGH WED NIGHT. AN UPPER LOW WILL THEN TRANSITION OVER SD/NE BRINGING CONTINUED STORM CHANCES THURSDAY. BY FRIDAY SFC HIGH PRESSURE WILL BRIEFLY BUILD IN TO THE PLAINS BRINGING DRIER WEATHER. THEN A TROUGH MOVES THROUGH ON SAT EVEN AS ANOTHER LONG WAVE TROF TO THE WEST BEGINS TO EJECT UPPER LEVEL ENERGY INTO THE DAKOTAS. THIS MEANS TSTORMS WILL BE BACK IN THE FORECAST FOR THE WEEKEND. TEMPERATURES WILL BE NEAR OR BELOW NORMAL THROUGH THE PERIOD DUE TO RAIN AND CLOUD COVER. GOOD MIXING ON MOST DAYS EXCEPT FRIDAY WILL PUSH HIGHS INTO THE 60S. && .AVIATION... 12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS EXPECT VFR CEILINGS THROUGH TODAY AND TONIGHT AT ALL LOCATIONS. ALSO...EXPECT SOME LIGHT RAIN SHOWERS WITH A SHORT WAVE TROUGH MOVING THROUGH THE REGION. SHOWERS WILL AFFECT KATY AND KABR THIS MORNING BEFORE EXITING. BREEZY SOUTHEAST WINDS WILL DEVELOP THIS MORNING NEAR KPIR AND KMBG. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...TMT LONG TERM...WISE AVIATION...WISE WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
956 AM EDT SUN MAY 4 2014 .SYNOPSIS... A FRONT WILL BECOME STATIONARY FROM VIRGINIA TO THE MID MISSISSIPPI VALLEY BY LATE TODAY. THIS BOUNDARY WILL REMAIN IN THE AREA THROUGH WEDNESDAY...THEN LIFT NORTH INTO NEW ENGLAND. THURSDAY AND FRIDAY HIGH PRESSURE ALOFT AND UNSEASONABLY WARM AIR BUILD OVER THE MID ATLANTIC REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 952 AM EDT... ADJUSTED TEMPERATURES AND DEW POINTS ACCORDING TO LATEST OBS AND MODEL TRENDS. SHORTWAVE TROUGH WILL PIVOT ACROSS THE REGION AROUND 00Z AND PUSHES OFFSHORE OVERNIGHT. THE SWODY1 BRINGS A CHANCE OF THUNDERSTORMS INTO WESTERN PORTIONS OF CWA. THE NAM...GFS AND ECMWF SUPPORT THE MENTION OF ISOLATED THUNDERSTORMS IN THE WEST. THE LOCAL RNK WRF ARW KEPT THE THUNDERSTORM AND SHOWER THREAT NORTH OF CWA THROUGH THIS AFTERNOON. WINDS WILL BE GUSTING OUT OF THE NORTHWEST THIS AFTERNOON...THIS WILL HINDER COVERAGE OF ANY SHOWERS OR THUNDERSTORMS EAST OF THE BLUE RIDGE. HELD ON TO CURRENT FORECAST HIGHS FROM THE UPPER 60S IN THE NORTHWEST MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT. AS OF 400 AM EDT SUNDAY... CLOSED UPPER LOW OVER THE GREAT LAKES MOVES ACROSS NEW ENGLAND BY THIS AFTERNOON. THIS KEEPS THE FORECAST AREA IN DEEP NORTHWEST FLOW THROUGH TONIGHT. WEAK STATIONARY FRONT WITH AXIS OF DEEPER MOISTURE SETS UP FROM SOUTHERN INDIANA TO CENTRAL VIRGINIA TODAY. MODELS STILL DIFFER IN EXACT ALIGNMENT OF WHERE PRECIPITATION MAY ENTER THE COUNTY WARNING AREA LATE THIS AFTERNOON. BETTER INSTABILITY REMAINS JUST WEST OF THE FORECAST AREA THROUGH MID AFTERNOON. THUNDERSTORMS THAT DEVELOP TO THE WEST WILL TRACK INTO THE AREA LATE TODAY. RAP GUIDANCE HAS PRECIPITATION AFTER 2PM AS FAR NORTHERN AS GREENBRIER COUNTY...WHILE THE NAM AND GFS WERE POINTING MORE TOWARD TAZEWELL AND SMYTH COUNTIES. PLENTY OF SUNSHINE THIS MORNING TO PRODUCE DEEP MIXING. WINDS WILL BE GUSTING OUT OF THE NORTHWEST SO COVERAGE OF ANY SHOWERS OR THUNDERSTORMS THAT GET ACROSS THE BLUE RIDGE WILL BE LIMITED. BUFKIT SUPPORTED WIND GUSTS OF 30 TO 40 MPH ABOVE 3000 FEET THIS AFTERNOON AND EARLY EVENING WITH WIND SPEEDS DROPPING OFF QUICKLY WITH THE LOSS OF HEATING. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM EDT SUNDAY... AN UPPER TROUGH BUILDING ALONG THE WEST COAST WILL EVENTUALLY CARVE A CLOSED UPPER LOW OVER SOUTHERN CALIFORNIA BY TUESDAY. IN RESPONSE...HEIGHTS WILL BUILD THROUGH THE MISSISSIPPI RIVER VALLEY AND GREAT LAKES. CONFLUENCE OVER NEW ENGLAND WILL PRODUCE A SURFACE HIGH WHICH WILL WEDGE INTO VIRGINIA...PERHAPS SENDING SLIGHTLY COOLER AND DRIER AIR INTO SW VA. THE STRENGTH AND POSITION OF THIS DIFFUSE BOUNDARY WILL DETERMINE CHANCES FOR PRECIP TUESDAY AND WEDNESDAY. MONDAY HOLDS THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS...MAINLY RT 460 AND POINTS NORTH. ALTHOUGH SOME SREF MEMBERS ARE SENDING PRECIP SOUTH OF THIS LINE...THE OP GFS SEEMS TO CONTAIN CONVECTIVE FEEDBACK WITH A SPURIOUS VORT MAX OVER WESTERN NORTH CAROLINA AT 0Z TUES. HOWEVER...CAN`T TOTALLY RULE OUT SHOWERS AND A FEW STORMS NEAR THE NC/VA BORDER MONDAY. INSTABILITY DEFINITELY EXISTS ON MONDAY...AND OF COURSE WITH THE POSITION OF THE STATIONARY BOUNDARY...GOOD LLVL SHEAR IS ALSO A FACTOR. THE MISSING INGREDIENT IN THE STEW IS FORCING...AS THERE DOESN`T SEEM TO BE MUCH OF A TRIGGER FOR SURFACE PARCELS. PERHAPS A CLEARER SKY AND MORE SUNSHINE MONDAY MORNING WILL PROVIDE THAT EXTRA NUDGE NECESSARY. COULD BE AN ISOLATED STRONG STORM RT 460 AND NORTH MONDAY. SOME EASTERLY COMPONENT AND THE POSITION OF THE BOUNDARY OVER SW VA COULD KEEP LYH/ROA COOLER THAN BLF/JFZ/MKJ CORRIDOR BOTH TUESDAY AND WEDNESDAY. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 345 PM EDT SATURDAY... PROGRESSIVE PATTERN WILL BECOME MORE AMPLIFIED DURING THE PERIOD AS DEEP UPPER TROUGH DEVELOPS IN THE WESTERN U.S. AND TROUGHING DEEPENS OVER THE NORTHERN ATLANTIC. THIS WILL RESULT IN AN AMPLIFYING MID-LEVEL RIDGE THROUGH THE OH/TN VALLEY. THE LONG STANDING BAROCLINIC ZONE OF THE FIRST HALF OF THE WEEK WILL BEGIN TO LIFT NORTH OF THE REGION WEDNESDAY...BUT MODELS NOW INDICATING THAT IT WILL BE AT LEAST ONE DAY SLOWER TO EXIST TO THE NORTHEAST THAN EARLIER INDICATED. THUS...THERE REMAINS THE POTENTIAL FOR SHRA/TSRA TO AGAIN DEVELOP WED AFTERNOON. BY THIS TIME...THE BEST SUPPORT WILL BE ACROSS THE ALLEGHANY HIGHLANDS AND SHENANDOAH VALLEY NORTHWARD...OR MAINLY NORTH OF I-64. HAVE TAILORED POPS ACCORDINGLY. THU STILL LIKES A DRY AND WARM DAY AS THE UPPER RIDGE DRIFTS OVER THE REGION. FOR FRI-SAT...THE MODELS HAVE COME INTO BETTER AGREEMENT ON THE MOVEMENT OF THE CENTRAL U.S. TROUGH INTO THE EASTERN U.S. THE MAJORITY OF THE PCPN WILL REMAIN WEST OF THE CWA THROUGH FRI...BUT BY SAT LIKELY POPS APPEAR IN ORDER FOR THE WV COUNTIES DOWN THROUGH SW VA/NW NC. THIS SYSTEM STILL OFFERS THE NEXT BEST CHANCE FOR WIDESPREAD RAINFALL FOR THE CWA. TOO FAR OUT TO GET INTO ANY SPECIFIC DETAILS...BUT HIGH CHC TO LOW LIKELY POPS IN ORDER FOR WESTERN AREAS AS INDICATED AND IN AGREEMENT WITH OUR WESTERN NEIGHBORS FOR NEXT SAT. MODELS SHOW A DISTINCT COOLING TREND FOR WED THAT APPEARS CONTRARY TO THE AMPLIFYING RIDGE. HOWEVER...A WEAK WEDGE PATTERN APPEARS EVIDENT UNDER THE AMPLIFYING RIDGE...WHICH COULD TEMPER THE WARMING ALOFT. AGAIN...HAVE GONE WITH A GENERAL MODEL BLEND. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... AS OF 730 AM EDT SUNDAY... ONLY SCATTERED CLOUDS ARE EXPECTED THROUGH MID MORNING WITH NO REDUCTION IN VISIBILITY. A WEAK FRONT WILL EXTEND ACROSS KENTUCKY INTO WESTERN VIRGINIA THIS AFTERNOON AND TONIGHT. THIS BOUNDARY WILL PROVIDE SOME LOW LEVEL CONVERGENCE...ENOUGH TO DEVELOP SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. HAVE KEPT SHOWERS IN THE BCB/BLF/LWB AND ROA TAFS AFTER 20Z/4PM TODAY BUT REMOVED THUNDERSTORMS SINCE THE PROBABILITY OF A STORM AT THESE AIRPORTS IS VERY LOW. WINDS WILL BEGIN GUSTING ONCE MORNING INVERSION MIXES OUT...AROUND 15Z/11AM. HIGH CONFIDENCE THAT WINDS GUSTS FROM 25 TO 30 KNOTS WILL BE COMMON THIS AFTERNOON. WINDS WILL DIMINISH THIS EVENING AROUND SUNSET. TONIGHT INTO WEDNESDAY...THE FRONT WILL STALL OVER THE FORECAST AREA. IMPULSES ALONG THIS BOUNDARY WILL BRING AN INCREASING CHANCE FOR SUB-VFR CEILINGS AND PERIODS OF SHRA/TSRA. THURSDAY THE FRONT LIFTS NORTH WITH DRIER WEATHER AND WARMER AIR MOVING INTO THE REGION. && .FIRE WEATHER... IN COORDINATION WITH NC FORESTRY OFFICIALS AND SURROUNDING NATIONAL WEATHER SERVICE OFFICES...HAVE ISSUED A SPECIAL WEATHER STATEMENT FOR ENHANCED FIRE DANGER THIS AFTERNOON IN THE NORTH CAROLINA FOOTHILLS. MOST CRITICAL CONDITIONS WILL BE FROM NOON THROUGH 8PM WHEN HUMIDITIES WILL BE AS LOW AS 25 PERCENT AND WIND WILL BE GUSTING FROM THE NORTHWEST AT 20 TO 30 MPH. OVERALL THESE COUNTIES DID NOT RECEIVE HIGH RAINFALL AMOUNTS FROM THE STORM SYSTEM LAST WEEK SO FUELS HAVE BECOME DRY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/KK SHORT TERM...KM LONG TERM...RAB AVIATION...AMS FIRE WEATHER...AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
732 AM EDT SUN MAY 4 2014 .SYNOPSIS... A FRONT WILL BECOME STATIONARY FROM VIRGINIA TO THE MID MISSISSIPPI VALLEY BY LATE TODAY. THIS BOUNDARY WILL REMAIN IN THE AREA THROUGH WEDNESDAY...THEN LIFT NORTH INTO NEW ENGLAND. THURSDAY AND FRIDAY HIGH PRESSURE ALOFT AND UNSEASONABLY WARM AIR BUILD OVER THE MID ATLANTIC REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 400 AM EDT SUNDAY... CLOSED UPPER LOW OVER THE GREAT LAKES MOVES ACROSS NEW ENGLAND BY THIS AFTERNOON. THIS KEEPS THE FORECAST AREA IN DEEP NORTHWEST FLOW THROUGH TONIGHT. WEAK STATIONARY FRONT WITH AXIS OF DEEPER MOISTURE SETS UP FROM SOUTHERN INDIANA TO CENTRAL VIRGINIA TODAY. MODELS STILL DIFFER IN EXACT ALIGNMENT OF WHERE PRECIPITATION MAY ENTER THE COUNTY WARNING AREA LATE THIS AFTERNOON. BETTER INSTABILITY REMAINS JUST WEST OF THE FORECAST AREA THROUGH MID AFTERNOON. THUNDERSTORMS THAT DEVELOP TO THE WEST WILL TRACK INTO THE AREA LATE TODAY. RAP GUIDANCE HAS PRECIPITATION AFTER 2PM AS FAR NORTHERN AS GREENBRIER COUNTY...WHILE THE NAM AND GFS WERE POINTING MORE TOWARD TAZEWELL AND SMYTH COUNTIES. PLENTY OF SUNSHINE THIS MORNING TO PRODUCE DEEP MIXING. WINDS WILL BE GUSTING OUT OF THE NORTHWEST SO COVERAGE OF ANY SHOWERS OR THUNDERSTORMS THAT GET ACROSS THE BLUE RIDGE WILL BE LIMITED. BUFKIT SUPPORTED WIND GUSTS OF 30 TO 40 MPH ABOVE 3000 FEET THIS AFTERNOON AND EARLY EVENING WITH WIND SPEEDS DROPPING OFF QUICKLY WITH THE LOSS OF HEATING. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM EDT SUNDAY... AN UPPER TROUGH BUILDING ALONG THE WEST COAST WILL EVENTUALLY CARVE A CLOSED UPPER LOW OVER SOUTHERN CALIFORNIA BY TUESDAY. IN RESPONSE...HEIGHTS WILL BUILD THROUGH THE MISSISSIPPI RIVER VALLEY AND GREAT LAKES. CONFLUENCE OVER NEW ENGLAND WILL PRODUCE A SURFACE HIGH WHICH WILL WEDGE INTO VIRGINIA...PERHAPS SENDING SLIGHTLY COOLER AND DRIER AIR INTO SW VA. THE STRENGTH AND POSITION OF THIS DIFFUSE BOUNDARY WILL DETERMINE CHANCES FOR PRECIP TUESDAY AND WEDNESDAY. MONDAY HOLDS THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS...MAINLY RT 460 AND POINTS NORTH. ALTHOUGH SOME SREF MEMBERS ARE SENDING PRECIP SOUTH OF THIS LINE...THE OP GFS SEEMS TO CONTAIN CONVECTIVE FEEDBACK WITH A SPURIOUS VORT MAX OVER WESTERN NORTH CAROLINA AT 0Z TUES. HOWEVER...CAN`T TOTALLY RULE OUT SHOWERS AND A FEW STORMS NEAR THE NC/VA BORDER MONDAY. INSTABILITY DEFINITELY EXISTS ON MONDAY...AND OF COURSE WITH THE POSITION OF THE STATIONARY BOUNDARY...GOOD LLVL SHEAR IS ALSO A FACTOR. THE MISSING INGREDIENT IN THE STEW IS FORCING...AS THERE DOESN`T SEEM TO BE MUCH OF A TRIGGER FOR SURFACE PARCELS. PERHAPS A CLEARER SKY AND MORE SUNSHINE MONDAY MORNING WILL PROVIDE THAT EXTRA NUDGE NECESSARY. COULD BE AN ISOLATED STRONG STORM RT 460 AND NORTH MONDAY. SOME EASTERLY COMPONENT AND THE POSITION OF THE BOUNDARY OVER SW VA COULD KEEP LYH/ROA COOLER THAN BLF/JFZ/MKJ CORRIDOR BOTH TUESDAY AND WEDNESDAY. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 345 PM EDT SATURDAY... PROGRESSIVE PATTERN WILL BECOME MORE AMPLIFIED DURING THE PERIOD AS DEEP UPPER TROUGH DEVELOPS IN THE WESTERN U.S. AND TROUGHING DEEPENS OVER THE NORTHERN ATLANTIC. THIS WILL RESULT IN AN AMPLIFYING MID-LEVEL RIDGE THROUGH THE OH/TN VALLEY. THE LONG STANDING BAROCLINIC ZONE OF THE FIRST HALF OF THE WEEK WILL BEGIN TO LIFT NORTH OF THE REGION WEDNESDAY...BUT MODELS NOW INDICATING THAT IT WILL BE AT LEAST ONE DAY SLOWER TO EXIST TO THE NORTHEAST THAN EARLIER INDICATED. THUS...THERE REMAINS THE POTENTIAL FOR SHRA/TSRA TO AGAIN DEVELOP WED AFTERNOON. BY THIS TIME...THE BEST SUPPORT WILL BE ACROSS THE ALLEGHANY HIGHLANDS AND SHENANDOAH VALLEY NORTHWARD...OR MAINLY NORTH OF I-64. HAVE TAILORED POPS ACCORDINGLY. THU STILL LIKES A DRY AND WARM DAY AS THE UPPER RIDGE DRIFTS OVER THE REGION. FOR FRI-SAT...THE MODELS HAVE COME INTO BETTER AGREEMENT ON THE MOVEMENT OF THE CENTRAL U.S. TROUGH INTO THE EASTERN U.S. THE MAJORITY OF THE PCPN WILL REMAIN WEST OF THE CWA THROUGH FRI...BUT BY SAT LIKELY POPS APPEAR IN ORDER FOR THE WV COUNTIES DOWN THROUGH SW VA/NW NC. THIS SYSTEM STILL OFFERS THE NEXT BEST CHANCE FOR WIDESPREAD RAINFALL FOR THE CWA. TOO FAR OUT TO GET INTO ANY SPECIFIC DETAILS...BUT HIGH CHC TO LOW LIKELY POPS IN ORDER FOR WESTERN AREAS AS INDICATED AND IN AGREEMENT WITH OUR WESTERN NEIGHBORS FOR NEXT SAT. MODELS SHOW A DISTINCT COOLING TREND FOR WED THAT APPEARS CONTRARY TO THE AMPLIFYING RIDGE. HOWEVER...A WEAK WEDGE PATTERN APPEARS EVIDENT UNDER THE AMPLIFYING RIDGE...WHICH COULD TEMPER THE WARMING ALOFT. AGAIN...HAVE GONE WITH A GENERAL MODEL BLEND. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AS OF 730 AM EDT SUNDAY... ONLY SCATTERED CLOUDS ARE EXPECTED THROUGH MID MORNING WITH NO REDUCTION IN VISIBILITY. A WEAK FRONT WILL EXTEND ACROSS KENTUCKY INTO WESTERN VIRGINIA THIS AFTERNOON AND TONIGHT. THIS BOUNDARY WILL PROVIDE SOME LOW LEVEL CONVERGENCE...ENOUGH TO DEVELOP SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. HAVE KEPT SHOWERS IN THE BCB/BLF/LWB AND ROA TAFS AFTER 20Z/4PM TODAY BUT REMOVED THUNDERSTORMS SINCE THE PROBABILITY OF A STORM AT THESE AIRPORTS IS VERY LOW. WINDS WILL BEGIN GUSTING ONCE MORNING INVERSION MIXES OUT...AROUND 15Z/11AM. HIGH CONFIDENCE THAT WINDS GUSTS FROM 25 TO 30 KNOTS WILL BE COMMON THIS AFTERNOON. WINDS WILL DIMINISH THIS EVENING AROUND SUNSET. TONIGHT INTO WEDNESDAY...THE FRONT WILL STALL OVER THE FORECAST AREA. IMPULSES ALONG THIS BOUNDARY WILL BRING AN INCREASING CHANCE FOR SUB-VFR CEILINGS AND PERIODS OF SHRA/TSRA. THURSDAY THE FRONT LIFTS NORTH WITH DRIER WEATHER AND WARMER AIR MOVING INTO THE REGION. && .FIRE WEATHER... IN COORDINATION WITH NC FORESTRY OFFICIALS AND SURROUNDING NATIONAL WEATHER SERVICE OFFICES...HAVE ISSUED A SPECIAL WEATHER STATEMENT FOR ENHANCED FIRE DANGER THIS AFTERNOON IN THE NORTH CAROLINA FOOTHILLS. MOST CRITICAL CONDITIONS WILL BE FROM NOON THROUGH 8PM WHEN HUMIDITIES WILL BE AS LOW AS 25 PERCENT AND WIND WILL BE GUSTING FROM THE NORTHWEST AT 20 TO 30 MPH. OVERALL THESE COUNTIES DID NOT RECEIVE HIGH RAINFALL AMOUNTS FROM THE STORM SYSTEM LAST WEEK SO FUELS HAVE BECOME DRY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...KM LONG TERM...RAB AVIATION...AMS FIRE WEATHER...AMS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
702 AM CDT SUN MAY 4 2014 .UPDATE...THIS MORNING ISSUED AT 702 AM CDT SUN MAY 4 2014 A BAND OF STRONG 900 TO 500 MB FRONTOGENESIS WILL BRUSH NORTHEAST IOWA AND A SMALL PART OF SOUTHEAST MINNESOTA THIS MORNING. THIS BAND IS CURRENTLY PRODUCING A BAND OF RAIN ACROSS SOUTHWEST MINNESOTA AND NORTH CENTRAL IOWA. THE HRRR SEEMS TO HAVE THE BEST HANDLE ON THIS AND SHOWS THE BAND MOVING THROUGH OUR 5 WESTERN COUNTIES IN NORTHEAST IOWA. DUE TO THIS...RAISED THE RAIN CHANCES UP TO 50 PERCENT FROM 04.13Z TO 04.16Z. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN MAY 4 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST...RIDGING DOWNSTREAM OVER THE ROCKIES AND WESTERN PLAINS...AND MORE TROUGHING OVER THE GREAT LAKES. ON THE SOUTHWEST SIDE OF THIS GREAT LAKES TROUGH...A 100 KT JET STREAK NEAR 250MB EXTENDED FROM INTERNATIONAL FALLS MN TO TRAVERSE CITY MI PER RAP ANALYSIS. THIS JET STREAK WAS AIDING IN A MID LEVEL FRONTOGENESIS ZONE TO ITS SOUTHWEST OVER THE EASTERN DAKOTAS INTO SOUTHERN MN. EXTENSIVE MID CLOUDS FROM SOUTH DAKOTA EASTWARD TO LOCATIONS SOUTHWEST OF I-94 IN THE FORECAST AREA EXIST AS A RESULT OF THIS FRONTOGENESIS ZONE. RADAR IMAGERY DEPICTS TWO BANDS OF SHOWER ACTIVITY ACROSS SOUTH DAKOTA BUT NO PRECIPITATION HAS BEEN REPORTED DUE TO DRY LOW LEVEL AIR. BANDS ACROSS SOUTHERN SOUTH DAKOTA ACTUALLY PRODUCING SOME LIGHTNING FROM STEEPER MID LEVEL LAPSE RATES COMING OFF THE ROCKIES. 925MB DEWPOINT DEPRESSIONS WERE 10-15C AT 00Z AT BIS...ABR AND MPX...HELPING TO PREVENT RAIN FROM REACHING THE GROUND. ALONG WITH THE DRY AIR...COOLER AIR WAS ADVECTING SOUTHEASTWARD FROM CANADA INTO THE FORECAST AREA. 925MB TEMPS AT BIS AND ABR FELL 5-6C OVER THE PAST 24 HOURS. UPPER RIDGING OVER THE ROCKIES IS PROGGED TO SLIDE FULLY OVER THE PLAINS BY 12Z MONDAY...PUSHED AHEAD BY THE DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST. WITH THE FORECAST AREA STAYING ON THE EAST SIDE OF THE RIDGE AXIS...THIS FAVORS SUBSIDENCE AND DRYING WITH HIGH PRESSURE AT THE SURFACE. HOWEVER...THERE ARE TWO CAVEATS TO THIS GENERALITY. 1. THIS MORNING WITH THE MID-LEVEL FRONTOGENESIS ZONE AND RIGHT ENTRANCE REGION OF THE JET STREAK. MODELS HAVE DEFINITELY TRENDED WEAKER WITH THIS FRONTOGENESIS...EVEN JUST BETWEEN THE 03.18Z AND 04.00Z NAM. AS A RESULT...THE 04.00Z GFS/NAM/REGIONAL CANADIAN HAVE REALLY BACKED OFF ON THE IDEA OF RAIN ACROSS SOUTHERN MN...NORTHERN IA...SOUTHERN WI AND NORTHERN IL THIS MORNING. 04.06Z RAP AND 04.04Z HRRR...WHICH ARE MIMICKING NICELY WHAT HAS BEEN GOING ON IN THE DAKOTAS...ALSO ARE DRIER. THEREFORE...HAVE FOLLOWED SUIT AND REALLY LOWERED PRECIPITATION CHANCES. 2. 04.00Z NAM/REGIONAL CANADIAN/GFS/ECMWF DEPICT ANOTHER BAND OF MID LEVEL FRONTOGENESIS TO TRACK OUT OF NORTH DAKOTA THIS AFTERNOON AND ACROSS LOCATIONS MAINLY NORTH OF I-94 BETWEEN 06-12Z MONDAY. THERE WERE INDICATIONS IN PAST RUNS OF POSSIBLE PRECIPITATION FROM THIS BAND...BUT THE 04.00Z ARE THE MOST IMPRESSIVE THUS FAR. THEREFORE...HAVE ADDED 20 PERCENT CHANCES. STILL HAVE SOME CONCERNS FOR PRECIPITATION GIVEN HIGH PRESSURE PROGGED OVER UPPER MI...WHICH WOULD PROVIDE A FEED OF DRY LOW LEVEL AIR TO COUNTERACT RAIN FALLING TO THE SURFACE. COOLER TEMPERATURES ARE EXPECTED TODAY GIVEN 18Z 925MB TEMPS PROGGED AROUND 4C COMPARED TO 7-10C AT 18Z YESTERDAY. HIGHS SHOULD BE AT LEAST 5 IF NOT 10 DEGREES COOLER...COOLEST OVER NORTHEAST IOWA WITH MOST CLOUD COVER. BATCH OF MID CLOUDS COMING THROUGH WITH THE FRONTOGENESIS ZONE TONIGHT COMBINED WITH AN INCREASING SOUTHEAST 925MB WIND SHOULD HELP TEMPERATURES FROM BOTTOMING OUT TOO MUCH. GUIDANCE LOWS IN THE 30S SEEM REASONABLE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 230 AM CDT SUN MAY 4 2014 BAND OF MID LEVEL FRONTOGENESIS ALONG/NORTH OF I-94 LATE TONIGHT LOOKS TO QUICKLY MOVE OFF TO THE EAST MONDAY MORNING. ONLY THE 04.00Z NAM LINGERS SOME LIGHT RAIN OVER TAYLOR/CLARK COUNTIES AFTER 12Z MONDAY. THEREFORE...HAVE FOLLOWED THE PREVIOUS FORECAST AND KEPT MONDAY DRY FOR NOW. DRY WEATHER IN FACT SHOULD PREVAIL ACROSS MUCH OF THE FORECAST AREA THROUGH TUESDAY AS THE AREA REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE OVER THE WESTERN GREAT LAKES. THE MODERATING TREND IN TEMPERATURES FOR MONDAY THROUGH TUESDAY REMAINS CONSISTENT WITH 925MB READINGS CLIMBING TO 6-8C AT 18Z MONDAY AND 8- 10C AT 18Z TUESDAY. WITH SOME SUN...ESPECIALLY ON TUESDAY...SHOULD SEE HIGHS CLIMB INTO THE MID 50S/LOW 60S ON MONDAY AND LOW TO MID 60S ON TUESDAY. MONDAY NIGHT COULD BE RELATIVELY CHILLY ACROSS CENTRAL WISCONSIN WITH CALM WINDS AND DRY AIR IN PLACE. LOWS THERE MAY DIP CLOSE TO FREEZING. MODELS CONTINUE TO FORECAST AN ACTIVE WEATHER PATTERN FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT...IN RESPONSE TO A BIG PORTION OF A LONG WAVE UPPER TROUGH OVER THE WESTERN U.S. AT 00Z WEDNESDAY LIFTING NORTHEAST INTO THE REGION. THE BIGGEST CHANGE OVER THE LAST 24 HOURS WITH THIS PERIOD OF THE FORECAST IS THAT THE ASSOCIATED LOW PRESSURE SYSTEM LIFTING OUT OF THE CENTRAL PLAINS IS MUCH SLOWER TO CROSS THE AREA THURSDAY INTO THURSDAY NIGHT. A LOT OF THIS SLOWING APPEARS TO BE RELATED TO THE PORTION OF THE LONG WAVE TROUGH TAKING A MORE NORTHWESTWARD TRACK. HIGHLIGHTS... 1. ELEVATED CONVECTION TUESDAY NIGHT / WEDNESDAY MORNING. THIS SIGNAL HAS BEEN VERY CONSISTENT FOR THE PAST COUPLE OF DAYS. INCREASING 850MB MOISTURE TRANSPORT AND CAPE ARE PROGGED TO OCCUR OVER IOWA THROUGH THE NIGHT...NOSING INTO THE FORECAST AREA. SEEMS LIKELY TO AT LEAST GET ELEVATED CONVECTION AND POSSIBLY EVEN AN MCS. SHOULD AN MCS FORM...CORFIDI VECTORS WOULD SUPPORT THE IDEA OF THE 04.00Z NAM OF AN MCS TRACKING EAST-SOUTHEASTWARD ACROSS IOWA. IN ANY EVENT...GIVEN THE CONSISTENT SIGNAL...FELT INCREASE IN PRECIPITATION CHANCES SEEMS WARRANTED. WILL HAVE TO WATCH FOR POTENTIAL SEVERE WEATHER WITH LARGE HAIL THE MOST LIKELY CONCERN. 2. DURING THE DAY WEDNESDAY...04.00Z GFS/ECMWF DEPICT A LOT OF LIGHT PRECIP...MAINLY ALONG AND NORTH OF I-90 WHICH IS ALSO NORTH OF A WARM FRONT. SOUNDINGS SUGGEST THIS IS LOW LEVEL ISENTROPIC LIFT INDUCED BELOW A STRONG CAP...SO PERHAPS AFTER SOME MORNING STORMS WE END UP WITH A BUNCH OF DRIZZLE. THIS IDEA SEEMS REASONABLE WHICH ALSO MEANS A DECENT TEMPERATURE GRADIENT COULD SET UP OVER THE FORECAST AREA. 3. ANOTHER ROUND OF ELEVATED CONVECTION WEDNESDAY NIGHT IF THE 04.00Z GFS IS CORRECT...THOUGH THE 04.00Z ECMWF/CANADIAN SUGGEST THIS CONVECTION WOULD TAKE PLACE WELL NORTH OF THE FORECAST AREA WITH THE AREA UNDER THE 850MB MOISTURE TRANSPORT STREAM. FOR NOW MAINTAINED 20-50 PERCENT CHANCES. WEDNESDAY NIGHT IS LOOKING WARM AND HUMID AS WELL...ESPECIALLY COMPARED TO WHAT WE HAVE SEEN. 4. THURSDAY IS LOOKING MORE MESSY...ESPECIALLY FORECASTING THE HIGH TEMP. MODELS AGREE THE FORECAST AREA IS IN THE WARM SECTOR...WHICH NORMALLY SUGGESTS A CAPPED ATMOSPHERE. HOWEVER...THE 04.00Z ECMWF/CANADIAN/GFS ARE ALL POINTING TO A WARM CONVEYOR BELT OF SHOWERS AND STORMS ACROSS MUCH OF THE FORECAST AREA AHEAD OF THE SHORTWAVE TROUGH LIFTING THROUGH THE PLAINS. 04.00Z ECMWF HAS CUT HIGHS 5-8 DEGREES AS A RESULT. THUS...FOR NOW HAVE LEFT A CONSENSUS HIGH IN THE 70S. STILL...THIS IS MUCH WARMER THAN WHERE WE HAVE BEEN. 5. POSSIBLE SEVERE WEATHER LATE THURSDAY/THURSDAY NIGHT. GIVEN THE NORTHWESTWARD TREND OF THE PLAINS TROUGH...SLOWER COLD FRONTAL TIMING AND THAT WARM CONVEYOR BELT ON THURSDAY LIMITING DAYTIME INSTABILITY...VERY UNCLEAR ON HOW THURSDAY NIGHT WILL PLAY OUT. WOULDNT DOUBT THE FORECAST AREA IS IMPACTED BY STORMS...AND THUS HAVE 50-60 PERCENT CHANCES GOING. HOWEVER...THE TIMING MAY KEEP THE SEVERE CONCERN WEST OF THE AREA. MANY DAYS TO WORK OUT THE DETAILS. MAINTAINED SOME CHANCES FOR FRIDAY WITH POTENTIAL LINGERING SHOWERS ON THE WRAP AROUND OF THE SYSTEM. MUCH COOLER TEMPS FOR FRIDAY TOO. DRIER WEATHER FOLLOWS FOR FRIDAY NIGHT WITH HIGH PRESSURE SLIDING THROUGH...THEN A COLD FRONT LOOKS TO APPROACH FOR SATURDAY TO BRING THE NEXT CHANCE OF RAIN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 637 AM CDT SUN MAY 4 2014 A SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH SOUTHWEST MINNESOTA...AND WESTERN AND SOUTHERN IOWA THIS MORNING. HRRR SUGGESTS THAT THE BEST CHANCE OF RAIN WITH THIS SYSTEM WILL BE IN NORTHEAST IOWA BETWEEN 04.13 AND 04.17Z. HOWEVER THE RAP AND NAM BUFKIT SOUNDINGS STILL SUGGEST THAT THERE MAY BE SPRINKLE AT KRST BETWEEN 04.16Z AND 04.20Z...SO KEPT THE VCSH IN THE TAF. FURTHER EAST...IT WILL BE JUST TOO DRY FOR ANY PRECIPITATION SO KEPT THE KLSE TAF DRY. CEILINGS WILL RISE INTO THE 9 TO 13K IN THE WAKE OF THIS SYSTEM THIS AFTERNOON...AND THEN LOWER ONCE AGAIN INTO THE 5 TO 10K FOOT RANGE FOR TONIGHT AS YET ANOTHER WAVE PASSES TO OUR SOUTHWEST. && .HYDROLOGY... ISSUED AT 230 AM CDT SUN MAY 4 2014 FLOODING CONTINUES ALONG THE MAINSTEM MISSISSIPPI RIVER AS RUNOFF FROM MELTING SNOW AND ALL OF THE RAINFALL OVER THE PAST 7-10 DAYS MOVES THROUGH THE WATERSHED. MOST OF THE TRIBUTARIES ARE FALLING AND SHOULD CONTINUE TO DO SO THE NEXT FEW DAYS. FOR THE MISSISSIPPI... CRESTS ARE EXPECTED FROM LAKE CITY THROUGH WABASHA AND ALMA ON MONDAY...AND ON TUESDAY FOR WINONA TO LA CROSSE. CRESTS WILL BE WEDNESDAY OR THURSDAY FROM GENOA THROUGH GUTTENBERG. FLOODING WILL REMAIN MINOR...THOUGH WINONA COULD GET CLOSE TO MODERATE FLOOD STAGE. REFER TO THE LATEST FLOOD STATEMENTS FOR DETAILS. NO LARGE RAIN AMOUNTS ARE ANTICIPATED UNTIL PERHAPS LATE TUESDAY NIGHT THROUGH THURSDAY NIGHT. THIS RAIN COULD SLOW THE RATE OF FALL OF THE MISSISSIPPI...BUT AT THIS TIME DOES NOT APPEAR AS IF IT WILL HAVE MUCH INFLUENCE ON THE CREST LEVEL. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BOYNE SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE HYDROLOGY...MW/AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
638 AM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN MAY 4 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST...RIDGING DOWNSTREAM OVER THE ROCKIES AND WESTERN PLAINS...AND MORE TROUGHING OVER THE GREAT LAKES. ON THE SOUTHWEST SIDE OF THIS GREAT LAKES TROUGH...A 100 KT JET STREAK NEAR 250MB EXTENDED FROM INTERNATIONAL FALLS MN TO TRAVERSE CITY MI PER RAP ANALYSIS. THIS JET STREAK WAS AIDING IN A MID LEVEL FRONTOGENESIS ZONE TO ITS SOUTHWEST OVER THE EASTERN DAKOTAS INTO SOUTHERN MN. EXTENSIVE MID CLOUDS FROM SOUTH DAKOTA EASTWARD TO LOCATIONS SOUTHWEST OF I-94 IN THE FORECAST AREA EXIST AS A RESULT OF THIS FRONTOGENESIS ZONE. RADAR IMAGERY DEPICTS TWO BANDS OF SHOWER ACTIVITY ACROSS SOUTH DAKOTA BUT NO PRECIPITATION HAS BEEN REPORTED DUE TO DRY LOW LEVEL AIR. BANDS ACROSS SOUTHERN SOUTH DAKOTA ACTUALLY PRODUCING SOME LIGHTNING FROM STEEPER MID LEVEL LAPSE RATES COMING OFF THE ROCKIES. 925MB DEWPOINT DEPRESSIONS WERE 10-15C AT 00Z AT BIS...ABR AND MPX...HELPING TO PREVENT RAIN FROM REACHING THE GROUND. ALONG WITH THE DRY AIR...COOLER AIR WAS ADVECTING SOUTHEASTWARD FROM CANADA INTO THE FORECAST AREA. 925MB TEMPS AT BIS AND ABR FELL 5-6C OVER THE PAST 24 HOURS. UPPER RIDGING OVER THE ROCKIES IS PROGGED TO SLIDE FULLY OVER THE PLAINS BY 12Z MONDAY...PUSHED AHEAD BY THE DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST. WITH THE FORECAST AREA STAYING ON THE EAST SIDE OF THE RIDGE AXIS...THIS FAVORS SUBSIDENCE AND DRYING WITH HIGH PRESSURE AT THE SURFACE. HOWEVER...THERE ARE TWO CAVEATS TO THIS GENERALITY. 1. THIS MORNING WITH THE MID-LEVEL FRONTOGENESIS ZONE AND RIGHT ENTRANCE REGION OF THE JET STREAK. MODELS HAVE DEFINITELY TRENDED WEAKER WITH THIS FRONTOGENESIS...EVEN JUST BETWEEN THE 03.18Z AND 04.00Z NAM. AS A RESULT...THE 04.00Z GFS/NAM/REGIONAL CANADIAN HAVE REALLY BACKED OFF ON THE IDEA OF RAIN ACROSS SOUTHERN MN...NORTHERN IA...SOUTHERN WI AND NORTHERN IL THIS MORNING. 04.06Z RAP AND 04.04Z HRRR...WHICH ARE MIMICKING NICELY WHAT HAS BEEN GOING ON IN THE DAKOTAS...ALSO ARE DRIER. THEREFORE...HAVE FOLLOWED SUIT AND REALLY LOWERED PRECIPITATION CHANCES. 2. 04.00Z NAM/REGIONAL CANADIAN/GFS/ECMWF DEPICT ANOTHER BAND OF MID LEVEL FRONTOGENESIS TO TRACK OUT OF NORTH DAKOTA THIS AFTERNOON AND ACROSS LOCATIONS MAINLY NORTH OF I-94 BETWEEN 06-12Z MONDAY. THERE WERE INDICATIONS IN PAST RUNS OF POSSIBLE PRECIPITATION FROM THIS BAND...BUT THE 04.00Z ARE THE MOST IMPRESSIVE THUS FAR. THEREFORE...HAVE ADDED 20 PERCENT CHANCES. STILL HAVE SOME CONCERNS FOR PRECIPITATION GIVEN HIGH PRESSURE PROGGED OVER UPPER MI...WHICH WOULD PROVIDE A FEED OF DRY LOW LEVEL AIR TO COUNTERACT RAIN FALLING TO THE SURFACE. COOLER TEMPERATURES ARE EXPECTED TODAY GIVEN 18Z 925MB TEMPS PROGGED AROUND 4C COMPARED TO 7-10C AT 18Z YESTERDAY. HIGHS SHOULD BE AT LEAST 5 IF NOT 10 DEGREES COOLER...COOLEST OVER NORTHEAST IOWA WITH MOST CLOUD COVER. BATCH OF MID CLOUDS COMING THROUGH WITH THE FRONTOGENESIS ZONE TONIGHT COMBINED WITH AN INCREASING SOUTHEAST 925MB WIND SHOULD HELP TEMPERATURES FROM BOTTOMING OUT TOO MUCH. GUIDANCE LOWS IN THE 30S SEEM REASONABLE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 230 AM CDT SUN MAY 4 2014 BAND OF MID LEVEL FRONTOGENESIS ALONG/NORTH OF I-94 LATE TONIGHT LOOKS TO QUICKLY MOVE OFF TO THE EAST MONDAY MORNING. ONLY THE 04.00Z NAM LINGERS SOME LIGHT RAIN OVER TAYLOR/CLARK COUNTIES AFTER 12Z MONDAY. THEREFORE...HAVE FOLLOWED THE PREVIOUS FORECAST AND KEPT MONDAY DRY FOR NOW. DRY WEATHER IN FACT SHOULD PREVAIL ACROSS MUCH OF THE FORECAST AREA THROUGH TUESDAY AS THE AREA REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE OVER THE WESTERN GREAT LAKES. THE MODERATING TREND IN TEMPERATURES FOR MONDAY THROUGH TUESDAY REMAINS CONSISTENT WITH 925MB READINGS CLIMBING TO 6-8C AT 18Z MONDAY AND 8- 10C AT 18Z TUESDAY. WITH SOME SUN...ESPECIALLY ON TUESDAY...SHOULD SEE HIGHS CLIMB INTO THE MID 50S/LOW 60S ON MONDAY AND LOW TO MID 60S ON TUESDAY. MONDAY NIGHT COULD BE RELATIVELY CHILLY ACROSS CENTRAL WISCONSIN WITH CALM WINDS AND DRY AIR IN PLACE. LOWS THERE MAY DIP CLOSE TO FREEZING. MODELS CONTINUE TO FORECAST AN ACTIVE WEATHER PATTERN FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT...IN RESPONSE TO A BIG PORTION OF A LONG WAVE UPPER TROUGH OVER THE WESTERN U.S. AT 00Z WEDNESDAY LIFTING NORTHEAST INTO THE REGION. THE BIGGEST CHANGE OVER THE LAST 24 HOURS WITH THIS PERIOD OF THE FORECAST IS THAT THE ASSOCIATED LOW PRESSURE SYSTEM LIFTING OUT OF THE CENTRAL PLAINS IS MUCH SLOWER TO CROSS THE AREA THURSDAY INTO THURSDAY NIGHT. A LOT OF THIS SLOWING APPEARS TO BE RELATED TO THE PORTION OF THE LONG WAVE TROUGH TAKING A MORE NORTHWESTWARD TRACK. HIGHLIGHTS... 1. ELEVATED CONVECTION TUESDAY NIGHT / WEDNESDAY MORNING. THIS SIGNAL HAS BEEN VERY CONSISTENT FOR THE PAST COUPLE OF DAYS. INCREASING 850MB MOISTURE TRANSPORT AND CAPE ARE PROGGED TO OCCUR OVER IOWA THROUGH THE NIGHT...NOSING INTO THE FORECAST AREA. SEEMS LIKELY TO AT LEAST GET ELEVATED CONVECTION AND POSSIBLY EVEN AN MCS. SHOULD AN MCS FORM...CORFIDI VECTORS WOULD SUPPORT THE IDEA OF THE 04.00Z NAM OF AN MCS TRACKING EAST-SOUTHEASTWARD ACROSS IOWA. IN ANY EVENT...GIVEN THE CONSISTENT SIGNAL...FELT INCREASE IN PRECIPITATION CHANCES SEEMS WARRANTED. WILL HAVE TO WATCH FOR POTENTIAL SEVERE WEATHER WITH LARGE HAIL THE MOST LIKELY CONCERN. 2. DURING THE DAY WEDNESDAY...04.00Z GFS/ECMWF DEPICT A LOT OF LIGHT PRECIP...MAINLY ALONG AND NORTH OF I-90 WHICH IS ALSO NORTH OF A WARM FRONT. SOUNDINGS SUGGEST THIS IS LOW LEVEL ISENTROPIC LIFT INDUCED BELOW A STRONG CAP...SO PERHAPS AFTER SOME MORNING STORMS WE END UP WITH A BUNCH OF DRIZZLE. THIS IDEA SEEMS REASONABLE WHICH ALSO MEANS A DECENT TEMPERATURE GRADIENT COULD SET UP OVER THE FORECAST AREA. 3. ANOTHER ROUND OF ELEVATED CONVECTION WEDNESDAY NIGHT IF THE 04.00Z GFS IS CORRECT...THOUGH THE 04.00Z ECMWF/CANADIAN SUGGEST THIS CONVECTION WOULD TAKE PLACE WELL NORTH OF THE FORECAST AREA WITH THE AREA UNDER THE 850MB MOISTURE TRANSPORT STREAM. FOR NOW MAINTAINED 20-50 PERCENT CHANCES. WEDNESDAY NIGHT IS LOOKING WARM AND HUMID AS WELL...ESPECIALLY COMPARED TO WHAT WE HAVE SEEN. 4. THURSDAY IS LOOKING MORE MESSY...ESPECIALLY FORECASTING THE HIGH TEMP. MODELS AGREE THE FORECAST AREA IS IN THE WARM SECTOR...WHICH NORMALLY SUGGESTS A CAPPED ATMOSPHERE. HOWEVER...THE 04.00Z ECMWF/CANADIAN/GFS ARE ALL POINTING TO A WARM CONVEYOR BELT OF SHOWERS AND STORMS ACROSS MUCH OF THE FORECAST AREA AHEAD OF THE SHORTWAVE TROUGH LIFTING THROUGH THE PLAINS. 04.00Z ECMWF HAS CUT HIGHS 5-8 DEGREES AS A RESULT. THUS...FOR NOW HAVE LEFT A CONSENSUS HIGH IN THE 70S. STILL...THIS IS MUCH WARMER THAN WHERE WE HAVE BEEN. 5. POSSIBLE SEVERE WEATHER LATE THURSDAY/THURSDAY NIGHT. GIVEN THE NORTHWESTWARD TREND OF THE PLAINS TROUGH...SLOWER COLD FRONTAL TIMING AND THAT WARM CONVEYOR BELT ON THURSDAY LIMITING DAYTIME INSTABILITY...VERY UNCLEAR ON HOW THURSDAY NIGHT WILL PLAY OUT. WOULDNT DOUBT THE FORECAST AREA IS IMPACTED BY STORMS...AND THUS HAVE 50-60 PERCENT CHANCES GOING. HOWEVER...THE TIMING MAY KEEP THE SEVERE CONCERN WEST OF THE AREA. MANY DAYS TO WORK OUT THE DETAILS. MAINTAINED SOME CHANCES FOR FRIDAY WITH POTENTIAL LINGERING SHOWERS ON THE WRAP AROUND OF THE SYSTEM. MUCH COOLER TEMPS FOR FRIDAY TOO. DRIER WEATHER FOLLOWS FOR FRIDAY NIGHT WITH HIGH PRESSURE SLIDING THROUGH...THEN A COLD FRONT LOOKS TO APPROACH FOR SATURDAY TO BRING THE NEXT CHANCE OF RAIN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 637 AM CDT SUN MAY 4 2014 A SHORT WAVE TROUGH WILL MOVE SOUTHEAST THROUGH SOUTHWEST MINNESOTA...AND WESTERN AND SOUTHERN IOWA THIS MORNING. HRRR SUGGESTS THAT THE BEST CHANCE OF RAIN WITH THIS SYSTEM WILL BE IN NORTHEAST IOWA BETWEEN 04.13 AND 04.17Z. HOWEVER THE RAP AND NAM BUFKIT SOUNDINGS STILL SUGGEST THAT THERE MAY BE SPRINKLE AT KRST BETWEEN 04.16Z AND 04.20Z...SO KEPT THE VCSH IN THE TAF. FURTHER EAST...IT WILL BE JUST TOO DRY FOR ANY PRECIPITATION SO KEPT THE KLSE TAF DRY. CEILINGS WILL RISE INTO THE 9 TO 13K IN THE WAKE OF THIS SYSTEM THIS AFTERNOON...AND THEN LOWER ONCE AGAIN INTO THE 5 TO 10K FOOT RANGE FOR TONIGHT AS YET ANOTHER WAVE PASSES TO OUR SOUTHWEST. && .HYDROLOGY... ISSUED AT 230 AM CDT SUN MAY 4 2014 FLOODING CONTINUES ALONG THE MAINSTEM MISSISSIPPI RIVER AS RUNOFF FROM MELTING SNOW AND ALL OF THE RAINFALL OVER THE PAST 7-10 DAYS MOVES THROUGH THE WATERSHED. MOST OF THE TRIBUTARIES ARE FALLING AND SHOULD CONTINUE TO DO SO THE NEXT FEW DAYS. FOR THE MISSISSIPPI... CRESTS ARE EXPECTED FROM LAKE CITY THROUGH WABASHA AND ALMA ON MONDAY...AND ON TUESDAY FOR WINONA TO LA CROSSE. CRESTS WILL BE WEDNESDAY OR THURSDAY FROM GENOA THROUGH GUTTENBERG. FLOODING WILL REMAIN MINOR...THOUGH WINONA COULD GET CLOSE TO MODERATE FLOOD STAGE. REFER TO THE LATEST FLOOD STATEMENTS FOR DETAILS. NO LARGE RAIN AMOUNTS ARE ANTICIPATED UNTIL PERHAPS LATE TUESDAY NIGHT THROUGH THURSDAY NIGHT. THIS RAIN COULD SLOW THE RATE OF FALL OF THE MISSISSIPPI...BUT AT THIS TIME DOES NOT APPEAR AS IF IT WILL HAVE MUCH INFLUENCE ON THE CREST LEVEL. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE HYDROLOGY...MW/AJ
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
406 PM MDT SUN MAY 4 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 405 PM MDT SUN MAY 4 2014 MODERATE WESTERLY FLOW ALOFT ROUNDING THE TOP OF A FLAT UPPER RIDGE UPPER LEVEL RIDGE WAS OVER COLORADO AT THIS TIME. AT THE SFC...LOW PRESSURE TROUGH SITS EAST OF THE MOUNTAINS WITH ITS AXIS STRADDLING THE NORTHEAST CORNER OF THE STATE. WEST OF THIS AXIS...GUSTY WEST-SOUTHWEST WINDS...VERY WARM TEMPERATURES AND DEWPOINTS IN THE SINGLE DIGITS AND TEENS PREVAIL. EAST OF THIS LINE...TEMPERATURES AS MUCH AS 10 DEGS COOLER...DEWPOINTS WERE IN THE 40S AND WINDS WERE GENERALLY EAST-SOUTHEAST IN DIRECTION. MOISTURE OUT THERE APPEARS SHALLOW AND THE LAYER ABOVE THIS WAS BECOMING INCREASINGLY DRIER WITH WESTERLY FLOW. DRY LINE ENVIRONMENT LOOKS TOO DRY AND STABLE FOR ANY CONVECTION/T-STORMS. DURING THE REMAINDER OF THE AFTERNOON...LATEST RAP SHOWS WEST- SOUTHWEST WINDS AND LOWER DEWPOINTS SPREADING EAST WITH THE SFC TROUGH ACROSS THE NORTHEAST CORNER. MEANWHILE WARM AND GUSTY SOUTHWEST WINDS WERE OCCURRING IN THE MTNS AND HIGH VALLEYS. WIND SPEEDS AND RH VALUES ACROSS SOUTH PARK...FIREWEATHER ZONE 241...MET RED FLAG WARNING CRITERIA A FEW HOURS AGO. THESE CONDITIONS SHOULD PERSIST THROUGH EARLY THIS EVENING. OVERNIGHT...SHOULD AGAIN SEE VERY MILD TEMPERATURES...PARTICULARLY IN AND NEAR THE FRONT RANGE...THOUGH NOT AS WARM AS LAST NIGHT. NAM SYNTHETIC IR SATELLITE IMAGERY ONCE AGAIN SHOWS A THICK MTN WAVE CLOUD FORMING ALONG THE FRONT RANGE LATER TONIGHT. SEE NO REASON TO DOUBT THIS WITH THE LONG FETCH OF HIGH ALTITUDE WATER VAPOR STREAMING EASTWARD ACROSS THE STATE. MONDAY SHOULD START OUT MOSTLY CLOUDY OVER AND ALONG THE FRONT RANGE WITH A THICK MTN WAVE CLOUD HANGING OVERHEAD. MODELS...NOTABLY THE RAP...SHOWS THE SFC TROUGH BACKING UP THE SOUTH PLATTE VALLEY...POSSIBLY AS FAR WEST AS GREELEY AND PLATTEVILLE BY MID- MORNING. MAY SEE PATCHY FOG WITH LOW 40S DEWPTS AND LIGHT EASTERLY WINDS BEHIND THIS WEAK SURGE. NAM SHOWS THE MTN WAVE CLOUD MOVING NORTH UP INTO WYOMING AROUND MIDDAY WITH CLEARING THROUGH THE AFTERNOON. HIGHS TOMORROW ARE FORECAST TO BE 1-3 DEG C LOWER THAN THOSE TODAY. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 405 PM MDT SUN MAY 4 2014 THE FLAT RIDGE OF HIGH PRESSURE WILL SHIFT EAST OF COLORADO ON MONDAY NIGHT IN RESPONSE TO DEEPENING TROF INTO THE GREAT BASIN. THE FLOW ALOFT WILL SHIFT TO THE SOUTHWEST ON TUESDAY WITH ONE MORE UNSEASONABLY WARM DAY WITH HIGHS AROUND 80 ACROSS LOWER ELEVATIONS. THE UPPER TROF WILL APPROACH COLORADO ON WEDNESDAY WHILE ASSOCIATED COLD FRONT DROPS SOUTHWARD OVER NORTHEAST COLORADO. EXPECT COOLER TEMPS ON WEDNESDAY AND EARLY THURSDAY WITH INCREASING CHANCES OF SHOWERS AND STORMS. AS THE LOW PULLS OUT ACROSS CENTRAL COLORADO THE LOW LEVEL FLOW SHIFTS NORTHWEST WHICH MAY LIMIT THE AMOUNT OF PRECIP POTENTIAL WITH DOWNSLOPE FLOW. A DRIER AND COOLER AIRMASS WILL SWEEP OVER COLORADO ON LATE THURSDAY AND FRIDAY AS THE FLOW ALOFT SHIFTS NORTHWEST. THERE STILL WILL BE SOME LINGERING MOISTURE FOR ISOLATED AFTERNOON AND EVENING THUNDERSTORMS. && .AVIATION...(FOR THE TAFS THROUGH 00Z MONDAY LATE AFTERNOON) ISSUED AT 405 PM MDT SUN MAY 4 2014 VFR CONDITIONS WILL PREVAIL NEXT 24 HOURS. WEST-SOUTHWEST WINDS OF 10-15KTS CAN BE EXPECTED AT DENVER AREA TERMINALS. ALTHOUGH RECENT WINDS AT KDEN HAVE BEEN FROM A NORTH-NORTHEAST DIRECTION. NOT SURE WE`LL SEE WEST-SOUTHWEST WINDS AT DIA...EVEN THOUGH THEY ARE VERY CLOSE BY. OVERNIGHT...WINDS WILL GO DRAINAGE AT 7-12KTS AS ANOTHER THICK MTN WAVE CLOUD FORMS ALONG THE FRONT RANGE. ON MONDAY...LOOK FOR SOUTH-SOUTHEAST WINDS OF 5-10KTS IN THE MORNING AND SOUTH TO SOUTHWEST WINDS OF 8-15KTS IN THE AFTERNOON UNDER CLEAR TO PARTLY CLOUDY SKIES. && .BOU WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL 7 PM MDT THIS EVENING FOR COZ214. && $$ SHORT TERM...BAKER LONG TERM...ENTREKIN AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS NEW YORK NY
220 PM EDT SUN MAY 4 2014 .SYNOPSIS... A COLD FRONT WILL APPROACH AND PASS THROUGH THIS AFTERNOON. HIGH PRESSURE WILL THEN BUILD DOWN FROM SOUTHERN CANADA THROUGH THE MIDDLE OF NEXT WEEK. A WARM FRONT WILL APPROACH FROM THE SOUTHWEST THURSDAY INTO FRIDAY...THEN LIFT TO THE NORTH FRIDAY NIGHT. A COLD FRONT WILL APPROACH FROM THE WEST ON SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... PREVIOUS UPDATE PRETTY MUCH ON TRACK. JUST MADE SLIGHT CHANGES TO HOURLY GRIDS BASED ON RECENT TRENDS. REGARDING CLOUD COVER...TRICKY TO DEPICT TRENDS IN THE CLOUD COVER GRIDS ACROSS THE AREA AS GENERALLY VARYING AMOUNTS OF CLOUDS WILL BE SEEN THROUGH THE DAY. AS FOR POPS...A FEW FACTORS COME INTO PLAY...AND AM NOT CONFIDENT ENOUGH THAT ALL INGREDIENTS COME TOGETHER AT ANY LOCATION AT ANY POINT IN TIME TO WARRANT LIKELY POPS. THEREFORE HAVE THE ENTIRE AREA AT HIGHER-END CHANCE POPS THIS AFTERNOON. THIS MIGHT EVEN BE TOO HIGH FOR SOME SPOTS...ESPECIALLY FOR THE NW ZONES. LIFT WILL BE GOOD AS A COLD FRONT/SURFACE TROUGH MOVES THROUGH THIS AFTERNOON. AT THE SAME TIME...PVA FROM AN APPROACHING SHORTWAVE ALOFT AND SYNOPTIC LIFT FROM A JET STREAK WILL ENHANCE OVERALL LIFT. THE PROBLEM IS THAT THERE APPEARS TO BE SHORT WINDOW THIS AFTERNOON WHERE THIS LIFT WILL BE ABLE TO WORK WITH SUFFICIENT MOISTURE TO PRODUCE SHOWERS. DEW POINTS WILL BE IN THE 30S AND CAPE WILL BE VERY LOW...BUT SINCE THE AFOREMENTIONED LIFT WILL BE OCCURRING AT A TIME WHERE MID LEVEL LAPSE RATES WILL BE CONDITIONALLY UNSTABLE...AND ALMOST STRONGLY UNSTABLE FOR SOME SPOTS (MAINLY EASTERN ZONES WHERE COLD POOL ALOFT WILL BE MORE SIGNIFICANT)...WILL KEEP IN AN ISOLATED THUNDERSTORM IN THE FORECAST. RUNS OF HRRR AND RAP13 SINCE THIS MORNING HAVE BEEN KEYING IN ON THE SOUTHERN ZONES FOR THE BEST CHANCES OF SHOWERS...APPARENTLY DUE TO MOISTURE CONVERGENCE ALONG THE COLD FRONT/TROUGH. WITH THE RELATIVELY DRY LOWER LEVELS...AND A MEAN OF AROUND 30KT WINDS IN THE BOUNDARY LAYER...ANY HEAVIER SHOWERS COULD PRODUCE WIND GUSTS PERHAPS AS HIGH AS AROUND 50MPH. OUTSIDE OF SHOWERS...DEEP MIXING WILL ALLOW FOR WESTERLY GUSTS OF 30-40 MPH. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... COLD FRONT CLEARS THE REGION BY THIS EVENING...TAPERING OFF ANY PRECIPITATION CHANCES BY THE END OF THE EVENING. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE BEFORE 00Z...WITH INSTABILITY DIMINISHING AND THE UPPER LEVEL FORCING PUSHING ON TO THE SOUTH. THE UPPER LEVEL CLOSED LOW PUSHES OFF TO THE EAST...BUT KEEPS THE REGION UNDER A BROAD TROUGH AND CYCLONIC FLOW ON THROUGH MONDAY. THIS WILL DO LITTLE MORE THAN KEEP THE MENTION OF PARTLY CLOUDY SKIES IN THE FORECAST AS HIGH PRESSURE BUILDING IN FROM THE NORTH WILL HELP TO DRY THE REGION. AS THE HIGH BUILDS IN...PRESSURE GRADIENT REMAINS TIGHT TONIGHT...AND COMBINING WITH A SHOT OF CAA WITH THE NORTHWESTERLY FLOW...WILL HELP TO KEEP WINDS ELEVATED THROUGH THE NIGHT. AS THE GRADIENT SLACKENS MONDAY WITH THE HIGH BECOMING THE MORE DOMINATING FEATURE...WINDS WILL DIMINISH. DESPITE COOLER TEMPERATURES MOVING IN...STILL EXPECTING TEMPS TO REMAIN NEAR NORMAL IN THE 60S FOR THE AREA. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... CLOSED LOW SLOWLY DEPARTS TO THE E FROM THE CANADIAN MARITIMES MONDAY-TUESDAY. WILL HAVE DOWNSLOPE NW FLOW...BUT CYCLONIC CURVATURE AROUND DEPARTING CUTOFF SHOULD ALLOW FOR A FEW CLOUDS. DEEP LAYERED RIDGE BUILDS TOWARDS THE AREA FROM TUESDAY NIGHT- FRIDAY...THEN SLIDES TO THE EAST INTO SATURDAY. ASSOCIATED SUBSIDENCE SHOULD KEEP THINGS DRY...AND WITH MINIMAL CLOUD COVER TUESDAY NIGHT-WEDNESDAY. FORECAST THEN BECOMES A BIT TRICKY WEDNESDAY NIGHT-SATURDAY. A STALLED FRONTAL BOUNDARY OVER THE MID-SOUTH AND SOUTHEAST IN THE MIDDLE OF THE WEEK...LIFTS NE AS A WARM FRONT STARTING WEDNESDAY NIGHT...AS ONSHORE RETURN FLOW DEVELOPS OVER THE AREA. SO SHOULD BEGIN TO SEE INCREASE IN CLOUDS AHEAD OF THE WARM FRONT FROM SW TO NE WEDNESDAY NIGHT. MODELS DIFFER OVER HOW QUICKLY TO BRING IN ANY RAIN ON THURSDAY - FIGURE THAT SUBSIDENCE UNDER THE BUILDING RIDGE SHOULD SERVE AS A LIMITING FACTOR. SO HAVE RESTRICTED CHANCE POPS TO THE AFTERNOON...AND THEN ONLY OVER THE SW 2/3 OF THE CWA. DOES APPEAR SOLID AGREEMENT THAT SHOULD SEE SOME RAIN THURSDAY NIGHT - SO HAVE CHANCE POPS THROUGHOUT. ECMWF AND GFS BOTH HAVE WARM FRONT STAYING TO THE S THROUGH THE DAY ON FRIDAY...SO SHOULD BE A GREY DAMP/POSSIBLY WET DAY - WITH SUBSIDENCE UNDER THE RIDGE A MITIGATING FACTOR - PLUS SHOULD BE ON THE COOL SIDE DUE TO CLOUD COVER/PRECIP AND E LOW LEVEL FLOW. CONTINUE TO FOLLOW CONSENSUS IDEA OF WARM FRONT LIFTING TO THE N FRIDAY NIGHT...LIKE THE LAST SYSTEM...BUT WOULD NOT BE SURPRISED IF IT ENDED UP DELAYING UNTIL SATURDAY MORNING. COLD FRONT STAYS TO THE WEST THROUGH THE DAY ON SATURDAY...SO SHOULD BE SOLIDLY IN THE WARM SECTOR THEN. NOTING IN WARM SECTOR ON SATURDAY...PLUS FORECAST SHOWALTER INDICES NEAR TO BELOW ZERO FRIDAY NIGHT AND SATURDAY - HAVE PUT A SLIGHT CHANCE OF THUNDER IN BOTH PERIODS TO GO WITH THE CHANCE OF SHOWERS. FOR TEMPERATURES TUESDAY NIGHT-SATURDAY USED A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE. ALSO BLENDED IN ECMWF 2-METER TEMPERATURES ON FRIDAY TO REFLECT IMPACT OF ONSHORE FLOW/CLOUD COVER/PRECIP. HAVE A FEELING THAT IF THINGS PLAY OUT AS CURRENTLY FORECAST...THAT WILL ULTIMATELY END UP STRUGGLING TO GET TEMPERATURES OUT OF THE 50S ON FRIDAY - FOR NOW WENT MAINLY IN THE 60S. FOR NOW GOING WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TUESDAY NIGHT-FRIDAY (WITH CAVEAT FOR FRIDAY AS STATED ABOVE)...THEN ABOVE NORMAL TEMPERATURES FRIDAY NIGHT AND SATURDAY. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... A COLD FRONT WILL MOVE ACROSS BY THIS EVENING. ACCOMPANYING SHOWERS OVER NORTHEAST PA AND NORTHWEST NJ AS OF 18Z SHOULD SLIDE E-SE TOWARD THE LOWER HUDSON VALLEY AND NYC METRO...WITH THE MAIN IMPACTS TO THE NYC METRO TERMINALS BETWEEN 1930Z-2200Z. MVFR VSBY IS POSSIBLE...AND STRONG SFC WIND GUSTS TO 40-45 KT IF A STRONGER CELL MOVES DIRECTLY OVERHEAD. IMPACTS FROM SHOWERS SHOULD BE LOWER TO THE NORTH/EAST AT KSWF/KBDR/KGON...BUT CANNOT RULE OUT ISOLD TO WIDELY SCT ACTIVITY THERE. W FLOW GUSTING AT OR JUST OVER 30 KT AT THE NYC METRO TERMINALS/KSWF...AND 25-30 KT ELSEWHERE...SHOULD BACK NW THIS EVENING AFTER COLD FROPA...REMAINING LEFT OF 310 MAGNETIC UNTIL LATE TONIGHT OR EARLY MON MORNING. WINDS/GUSTS ONLY WEAKEN SLIGHTLY TONIGHT. .OUTLOOK FOR 18Z MON THROUGH THU... .MON AFTERNOON...VFR. NW WINDS G20KT...COULD BE ON TOP OF 310 MAGNETIC UNTIL LATE DAY. .MON NIGHT-WED NIGHT...VFR. .THU-FRI...CHANCE OF RAIN WITH MVFR OR LOWER CONDS. && .MARINE... WINDS AND WAVE FORECAST REMAIN ON TRACK. MINIMAL MIXING ON THE WATERS WILL HELP TO MINIMIZE THE GUSTS FARTHER OFFSHORE...WITH THE HIGHER GUSTS EXPECTED ALONG THE COASTS AND ACROSS THE BAYS OF LONG ISLAND WHERE BETTER MIXING WILL OCCUR. OVERALL...EXPECTING GUSTS TO 25 KT EVERYWHERE...AND AROUND 30 KT RIGHT AT THE COAST INTO TONIGHT. SEAS WILL BUILD ON THE OCEAN WATERS TO BETWEEN 4 AND 6 FT. THE SCA CONDITIONS ARE EXPECTED TO DIMINISH BY MONDAY MORNING AS THE PRESSURE GRADIENT RELAXES WITH THE HIGH BUILDING IN. FORECAST KEEPS ALL WATERS THEN BELOW SCA CONDITIONS FOR THE REMAINDER OF THE WEEK. && .HYDROLOGY... NO SIGNIFICANT RAINFALL IS EXPECTED THROUGH THU. THERE IS THE POSSIBILITY OF SIGNIFICANT RAINFALL FROM THURSDAY NIGHT INTO SATURDAY. AT THIS TIME...THERE IS TOO MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR POTENTIAL IMPACTS. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ330-335-338- 340-345-355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT/SEARS NEAR TERM...JC SHORT TERM...SEARS LONG TERM...MALOIT/SEARS AVIATION...GOODMAN MARINE...SEARS/PW HYDROLOGY...SEARS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1240 PM EDT SUN MAY 4 2014 .SYNOPSIS... COLD FRONT APPROACHES AND PASSES THROUGH THE REGION THIS AFTERNOON. HIGH PRESSURE THEN BUILDS DOWN SLOWLY FROM SOUTHERN CANADA THROUGH THE MIDDLE OF NEXT WEEK. A WARM FRONT WILL SLOWLY APPROACH FROM THE SOUTHWEST THURSDAY INTO FRIDAY...THEN LIFT TO THE NORTH FRIDAY NIGHT. A COLD FRONT APPROACHES FROM THE WEST ON SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... PREVIOUS UPDATE PRETTY MUCH ON TRACK. JUST MADE SLIGHT CHANGES TO HOURLY GRIDS BASED ON RECENT TRENDS. REGARDING CLOUD COVER...TRICKY TO DEPICT TRENDS IN THE CLOUD COVER GRIDS ACROSS THE AREA AS GENERALLY VARYING AMOUNTS OF CLOUDS WILL BE SEEN THROUGH THE DAY. AS FOR POPS...A FEW FACTORS COME INTO PLAY...AND AM NOT CONFIDENT ENOUGH THAT ALL INGREDIENTS COME TOGETHER AT ANY LOCATION AT ANY POINT IN TIME TO WARRANT LIKELY POPS. THEREFORE HAVE THE ENTIRE AREA AT HIGHER-END CHANCE POPS THIS AFTERNOON. THIS MIGHT EVEN BE TOO HIGH FOR SOME SPOTS...ESPECIALLY FOR THE NW ZONES. LIFT WILL BE GOOD AS A COLD FRONT/SURFACE TROUGH MOVES THROUGH THIS AFTERNOON. AT THE SAME TIME...PVA FROM AN APPROACHING SHORTWAVE ALOFT AND SYNOPTIC LIFT FROM A JET STREAK WILL ENHANCE OVERALL LIFT. THE PROBLEM IS THAT THERE APPEARS TO BE SHORT WINDOW THIS AFTERNOON WHERE THIS LIFT WILL BE ABLE TO WORK WITH SUFFICIENT MOISTURE TO PRODUCE SHOWERS. DEW POINTS WILL BE IN THE 30S AND CAPE WILL BE VERY LOW...BUT SINCE THE AFOREMENTIONED LIFT WILL BE OCCURRING AT A TIME WHERE MID LEVEL LAPSE RATES WILL BE CONDITIONALLY UNSTABLE...AND ALMOST STRONGLY UNSTABLE FOR SOME SPOTS (MAINLY EASTERN ZONES WHERE COLD POOL ALOFT WILL BE MORE SIGNIFICANT)...WILL KEEP IN AN ISOLATED THUNDERSTORM IN THE FORECAST. RUNS OF HRRR AND RAP13 SINCE THIS MORNING HAVE BEEN KEYING IN ON THE SOUTHERN ZONES FOR THE BEST CHANCES OF SHOWERS...APPARENTLY DUE TO MOISTURE CONVERGENCE ALONG THE COLD FRONT/TROUGH. WITH THE RELATIVELY DRY LOWER LEVELS...AND A MEAN OF AROUND 30KT WINDS IN THE BOUNDARY LAYER...ANY HEAVIER SHOWERS COULD PRODUCE WIND GUSTS PERHAPS AS HIGH AS AROUND 50MPH. OUTSIDE OF SHOWERS...DEEP MIXING WILL ALLOW FOR WESTERLY GUSTS OF 30-40 MPH. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... COLD FRONT CLEARS THE REGION BY THIS EVENING...TAPERING OFF ANY PRECIPITATION CHANCES BY THE END OF THE EVENING. AN ISOLATED THUNDERSTORM WILL BE POSSIBLE BEFORE 00Z...WITH INSTABILITY DIMINISHING AND THE UPPER LEVEL FORCING PUSHING ON TO THE SOUTH. THE UPPER LEVEL CLOSED LOW PUSHES OFF TO THE EAST...BUT KEEPS THE REGION UNDER A BROAD TROUGH AND CYCLONIC FLOW ON THROUGH MONDAY. THIS WILL DO LITTLE MORE THAN KEEP THE MENTION OF PARTLY CLOUDY SKIES IN THE FORECAST AS HIGH PRESSURE BUILDING IN FROM THE NORTH WILL HELP TO DRY THE REGION. AS THE HIGH BUILDS IN...PRESSURE GRADIENT REMAINS TIGHT TONIGHT...AND COMBINING WITH A SHOT OF CAA WITH THE NORTHWESTERLY FLOW...WILL HELP TO KEEP WINDS ELEVATED THROUGH THE NIGHT. AS THE GRADIENT SLACKENS MONDAY WITH THE HIGH BECOMING THE MORE DOMINATING FEATURE...WINDS WILL DIMINISH. DESPITE COOLER TEMPERATURES MOVING IN...STILL EXPECTING TEMPS TO REMAIN NEAR NORMAL IN THE 60S FOR THE AREA. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... CLOSED LOW SLOWLY DEPARTS TO THE E FROM THE CANADIAN MARITIMES MONDAY-TUESDAY. WILL HAVE DOWNSLOPE NW FLOW...BUT CYCLONIC CURVATURE AROUND DEPARTING CUTOFF SHOULD ALLOW FOR A FEW CLOUDS. DEEP LAYERED RIDGE BUILDS TOWARDS THE AREA FROM TUESDAY NIGHT- FRIDAY...THEN SLIDES TO THE EAST INTO SATURDAY. ASSOCIATED SUBSIDENCE SHOULD KEEP THINGS DRY...AND WITH MINIMAL CLOUD COVER TUESDAY NIGHT-WEDNESDAY. FORECAST THEN BECOMES A BIT TRICKY WEDNESDAY NIGHT-SATURDAY. A STALLED FRONTAL BOUNDARY OVER THE MID-SOUTH AND SOUTHEAST IN THE MIDDLE OF THE WEEK...LIFTS NE AS A WARM FRONT STARTING WEDNESDAY NIGHT...AS ONSHORE RETURN FLOW DEVELOPS OVER THE AREA. SO SHOULD BEGIN TO SEE INCREASE IN CLOUDS AHEAD OF THE WARM FRONT FROM SW TO NE WEDNESDAY NIGHT. MODELS DIFFER OVER HOW QUICKLY TO BRING IN ANY RAIN ON THURSDAY - FIGURE THAT SUBSIDENCE UNDER THE BUILDING RIDGE SHOULD SERVE AS A LIMITING FACTOR. SO HAVE RESTRICTED CHANCE POPS TO THE AFTERNOON...AND THEN ONLY OVER THE SW 2/3 OF THE CWA. DOES APPEAR SOLID AGREEMENT THAT SHOULD SEE SOME RAIN THURSDAY NIGHT - SO HAVE CHANCE POPS THROUGHOUT. ECMWF AND GFS BOTH HAVE WARM FRONT STAYING TO THE S THROUGH THE DAY ON FRIDAY...SO SHOULD BE A GREY DAMP/POSSIBLY WET DAY - WITH SUBSIDENCE UNDER THE RIDGE A MITIGATING FACTOR - PLUS SHOULD BE ON THE COOL SIDE DUE TO CLOUD COVER/PRECIP AND E LOW LEVEL FLOW. CONTINUE TO FOLLOW CONSENSUS IDEA OF WARM FRONT LIFTING TO THE N FRIDAY NIGHT...LIKE THE LAST SYSTEM...BUT WOULD NOT BE SURPRISED IF IT ENDED UP DELAYING UNTIL SATURDAY MORNING. COLD FRONT STAYS TO THE WEST THROUGH THE DAY ON SATURDAY...SO SHOULD BE SOLIDLY IN THE WARM SECTOR THEN. NOTING IN WARM SECTOR ON SATURDAY...PLUS FORECAST SHOWALTER INDICES NEAR TO BELOW ZERO FRIDAY NIGHT AND SATURDAY - HAVE PUT A SLIGHT CHANCE OF THUNDER IN BOTH PERIODS TO GO WITH THE CHANCE OF SHOWERS. FOR TEMPERATURES TUESDAY NIGHT-SATURDAY USED A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE. ALSO BLENDED IN ECMWF 2-METER TEMPERATURES ON FRIDAY TO REFLECT IMPACT OF ONSHORE FLOW/CLOUD COVER/PRECIP. HAVE A FEELING THAT IF THINGS PLAY OUT AS CURRENTLY FORECAST...THAT WILL ULTIMATELY END UP STRUGGLING TO GET TEMPERATURES OUT OF THE 50S ON FRIDAY - FOR NOW WENT MAINLY IN THE 60S. FOR NOW GOING WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TUESDAY NIGHT-FRIDAY (WITH CAVEAT FOR FRIDAY AS STATED ABOVE)...THEN ABOVE NORMAL TEMPERATURES FRIDAY NIGHT AND SATURDAY. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... A COLD FRONT WILL MOVE ACROSS BY THIS EVENING. CU ARE STARTING TO DEVELOP AHEAD OF THE FRONT OVER THE LOWER HUDSON VALLEY AND CT...AND IT APPEARS A BKN LINE OF SHOWERS AND ISOLD TSTMS SHOULD DEVELOP OVER OR JUST NORTH OF THE NYC METRO AND LONG ISLAND TERMINALS BY ABOUT 18Z...AND SLOWLY SPREAD SOUTH THROUGH THE REST OF THE AFTERNOON. CONFIDENT ENOUGH TO CONTINUE MENTION OF TEMPO MVFR CONDS...BUT IMPACTS COULD INCLUDE STRONG WIND GUSTS TO 40-45 KT IF A STRONGER CELL MOVES DIRECTLY OVERHEAD. IMPACTS FROM SHOWERS NOW LOOK LOWER TO THE NORTH ACROSS THE LOWER HUDSON VALLEY AND CT...BUT CANNOT RULE OUT WIDELY SCT ACTIVITY THERE ESPECIALLY ACROSS CT. W FLOW GUSTING AT OR JUST OVER 30 KT AT THE NYC METRO TERMINALS...AND 25-30 KT ELSEWHERE...SHOULD BACK NW THIS EVENING AFTER COLD FROPA...REMAINING LEFT OF 310 MAGNETIC. WINDS ONLY SLIGHTLY WEAKEN TONIGHT WITH GUSTS REMAINING. .OUTLOOK FOR 12Z MON THROUGH THU... .MON...VFR. NW WINDS G25KT...DIMINISHING IN THE AFTERNOON/EVENING. .MON NIGHT-WED NIGHT...VFR. .THU...CHANCE OF MVFR CONDS IN ANY RAIN. && .MARINE... WINDS AND WAVE FORECAST REMAIN ON TRACK. MINIMAL MIXING ON THE WATERS WILL HELP TO MINIMIZE THE GUSTS FARTHER OFFSHORE...WITH THE HIGHER GUSTS EXPECTED ALONG THE COASTS AND ACROSS THE BAYS OF LONG ISLAND WHERE BETTER MIXING WILL OCCUR. OVERALL...EXPECTING GUSTS TO 25 KT EVERYWHERE...AND AROUND 30 KT RIGHT AT THE COAST INTO TONIGHT. SEAS WILL BUILD ON THE OCEAN WATERS TO BETWEEN 4 AND 6 FT. THE SCA CONDITIONS ARE EXPECTED TO DIMINISH BY MONDAY MORNING AS THE PRESSURE GRADIENT RELAXES WITH THE HIGH BUILDING IN. FORECAST KEEPS ALL WATERS THEN BELOW SCA CONDITIONS FOR THE REMAINDER OF THE WEEK. && .HYDROLOGY... NO SIGNIFICANT RAINFALL IS EXPECTED THROUGH THU. THERE IS THE POSSIBILITY OF SIGNIFICANT RAINFALL FROM THURSDAY NIGHT INTO SATURDAY. AT THIS TIME...THERE IS TOO MUCH UNCERTAINTY TO SPECIFY EXACT AMOUNTS OR POTENTIAL IMPACTS. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ330-335-338- 340-345-355. SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT/SEARS NEAR TERM...JC SHORT TERM...SEARS LONG TERM...MALOIT/SEARS AVIATION...GOODMAN/JM MARINE...SEARS/PW HYDROLOGY...SEARS
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
623 PM EDT SUN MAY 4 2014 .SYNOPSIS... HIGH PRESSURE WILL PREVAIL THIS WEEK. A COLD FRONT COULD APPROACH THE REGION NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... HIGH PRESSURE WILL EXTEND ACROSS THE AREA TONIGHT. A BACKDOOR COLD FRONT WILL APPROACH FROM THE NORTH EARLY MONDAY...BUT IS EXPECTED TO REMAIN NORTH OF THE SOUTH SANTEE RIVER. KCLX REFLECTIVITY PRODUCTS SHOW A WELL-DEFINED SEA BREEZE MOVING INLAND AT 5-10 KT. THIS FEATURE WILL EVENTUALLY CLEAR THE FAR WESTERN AREAS LATER THIS EVENING BEFORE THE THERMALLY DIRECT CIRCULATION DISSIPATES. FOR THE EARLY EVENING UPDATE... 1. ADJUSTED HOURLY TEMPERATURES THROUGH 9 PM...INITIALIZING WITH THE 04/22Z OBSERVATIONS AND EXPECTED MOVEMENT OF THE RESULTANT SEA BREEZE. 2. INCREASED OVERNIGHT LOWS IN DOWNTOWN CHARLESTON BY SEVERAL DEGREES. 3. LOWERED WIND SPEEDS TO CALM WEST OF I-95 WHERE THE BOUNDARY LAYER IS EXPECTED TO DECOUPLE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... ONGOING FORECASTS FOR MONDAY THROUGH WEDNESDAY REMAIN ON TRACK...WITH ONLY MINOR ADJUSTMENTS WITHIN THE SUNDAY AFTERNOON PACKAGE. DEEP LAYER HIGH PRESSURE CENTERED S/SW OF THE REGION WILL MAINTAIN A SYNOPTIC DOWNSLOPE/OFFSHORE FLOW...PINNING THE AFTERNOON SEA BREEZE CLOSE TO THE COAST MONDAY AND TUESDAY. HIGH TEMPS IN THE LOWER 90S WILL BE COMMON...AND HIGHS WELL INTO THE 80S WILL LIKELY PUSH TO THE BEACHES BEFORE THE SEA BREEZE DEVELOPS. A COLD FRONT WILL STALL OVER N/NE SC WEDNESDAY...AND THE CENTER OF SURFACE HIGH PRESSURE WILL SHIFT OFFSHORE. THUS...THE SEA BREEZE WILL DEVELOP EARLIER AND WILL PUSH INLAND. THE MARINE INFLUENCE WILL LIMIT HIGH TEMPERATURES ON AREA BEACHES TO THE 70S AND SHOULD TRANSLATE INTO SLIGHTLY LOWER INLAND TEMPERATURES AS COMPARED WITH HIGHS EXPECTED MONDAY-TUESDAY. HOWEVER...GIVEN THE BUILDING UPPER RIDGE OVER THE REGION...HIGHS CLOSE TO 90F WILL STILL PREVAIL AWAY FROM THE COAST. LOW TEMPERATURES IN THE LOWER TO MIDDLE 60S INLAND AND AROUND 70F ON THE BEACHES WILL BE COMMON. NO PRECIPITATION IS EXPECTED AND POPS REMAIN VIRTUALLY ZERO THROUGH THE PERIOD. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... DRY AND UNSEASONABLY WARM WEATHER WILL PERSIST THROUGH FRIDAY AS THE DEEP LAYERED RIDGE REMAINS IN PLACE. A DE-AMPLIFYING UPPER TROUGH WILL SHIFT INTO THE EASTERN UNITED STATES NEXT WEEKEND...PUSHING A A COLD FRONT TOWARD THE REGION FROM THE WEST. PROGRESS OF THE FRONT IS UNCERTAIN AND COULD BE SLOWED IF DEEP LAYER RIDGING PERSISTS ALONG THE SOUTHEAST COAST. EVEN SO...MOISTURE SHOULD INCREASE SUFFICIENTLY TO MAINTAIN ONGOING SLIGHT CHANCE POPS SATURDAY NIGHT AND SUNDAY. WEEKEND HIGH TEMPS WILL COOL SLIGHTLY INTO THE LOWER TO MIDDLE 80S. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... VFR. EXTENDED AVIATION OUTLOOK...THERE ARE NO CONCERNS. && .MARINE... TONIGHT...LOWERED OVERNIGHT. WIND SPEEDS SLIGHTLY BASED ON 18Z MODEL AND SHORT TERM RAP MODEL DATA. EXPECT PEAK WINDS OF 10-15 KT...EXCEPT 15 KT CHARLESTON COUNTY WATERS AND PARTS OF THE GEORGIA OFFSHORE WATERS. SEAS 2-3 FT. MONDAY THROUGH TUESDAY...HIGH PRESSURE WILL BE CENTERED S/SW OF THE WATERS. AS A RESULT...DEEP LAYER OFFSHORE FLOW WILL DOMINATE MONDAY AND TUESDAY...AND THE SEA BREEZE CIRCULATION WILL CAUSE WINDS TO BACK TOWARD THE SW BOTH AFTERNOON. ALSO...04/12Z GUIDANCE SUGGEST THAT A MODEST NOCTURNAL SURGE OF SW WINDS WILL OCCUR EACH NIGHT...PERHAPS ACCOMPANIED BY OCCASIONAL GUSTS AS HIGH AS 20 KT ESPECIALLY MONDAY NIGHT. HOWEVER...WINDS WILL REMAIN BELOW SMALL CRAFT ADVISORY STRENGTH THROUGH THE FORECAST PERIOD. HIGH PRESSURE WILL SHIFT INTO THE WESTERN ATLANTIC MID TO LATE WEEK. AS A RESULT...SYNOPTIC SOUTHERLY FLOW WILL DEVELOP AND WILL SUPPORT AN ACTIVE SEA BREEZE CIRCULATION EACH MIDDAY THROUGH EARLY EVENING MID TO LATE WEEK. SEAS THROUGH THE PERIOD WILL RANGE FROM 1-3 FT WITHIN NEARSHORE WATERS TO AS HIGH AS 3-4 FT BEYOND 20 NM. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1233 PM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 812 AM CDT SUN MAY 4 2014 UPDATED ZONES TO INCLUDE SHOWER/SLEET MIX ACROSS THE FAR NORTH NEAR HANCOCK/WORTH/CERRO GORDO COUNTIES. RECENT REPORT OF MIXTURE IN THE PAST 30 MINUTES./REV && .SHORT TERM /TODAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST CONCERN FOR TODAY WILL BE PRECIPITATION CHANCES IN THE MORNING HOURS. CURRENTLY...PRECIPITATION IS BEGINNING TO FILL IN AND EXPAND IN CENTRAL SD/NORTHERN NE AS SHORTWAVE PUSHES SE. HIGH RES MODELS HAVE THE BEST HANDLE ON ONGOING PRECIPITATION...AND HAVE TRENDED TOWARDS HRRR AND CONSSHORT AND HAVE EXTENDED POPS FURTHER SOUTH AND WEST. HOWEVER...HAVE NOT BEEN AS AGGRESSIVE AS MODELS INDICATE GIVEN LARGE AMOUNT OF LOW LEVEL DRY AIR. SOUNDINGS STILL INDICATING MOISTURE SOMEWHAT LACKING IN CENTRAL CWA. THEREFORE...HAVE ALSO KEPT PRECIP MENTION SCATTERED/ISOLATED. SYSTEM WILL PUSH QUICKLY EAST/NORTHEAST WITH DRY CONDITIONS IN STORE FOR REMAINDER OF AFTERNOON AS WEAK RIDGE PUSHES IN. HAVE INCREASED TEMPERATURES WITH DECENT WAA...ESPECIALLY IN THE SOUTH. .LONG TERM /TONIGHT THROUGH FRIDAY/... ISSUED AT 330 AM CDT SUN MAY 4 2014 LONG TERM FORECAST WILL BE DOMINATED BY LARGE WESTERN TROF THAT EVENTUALLY TRACKS EASTWARD THROUGH THE REGION BY LATE IN THE WORK WEEK. PRIOR TO THE ARRIVAL HOWEVER...THE WEATHER WILL BE RELATIVELY TRANQUIL FROM TONIGHT INTO TUESDAY. SURFACE BOUNDARY WILL SET UP ACROSS MISSOURI DURING THIS TIME WITH DRY EASTERLY LOW-LEVEL FLOW ACROSS IOWA. WILL SEE WARM ADVECTION GETTING PROGRESSIVELY STRONGER THROUGH MONDAY INTO TUESDAY WITH HIGHS BY TUESDAY AFTERNOON GETTING CLOSE TO NORMAL. FRONT WILL BEGIN TO LIFT NORTHWARD INTO THE STATE TUESDAY NIGHT INTO WEDNESDAY IN RESPONSE TO DEVELOPING SURFACE LOW ACROSS THE PLAINS. INCREASING THETA-E ADVECTION ON TUESDAY NIGHT SHOULD LEAD TO DEVELOPMENT OF SCATTERED CONVECTION IN NORTHERN IOWA LATE. THIS CONVECTION MAY LINGER INTO WEDNESDAY MORNING IN THE FAR NORTH AS THERMAL RIDGE BUILDS INTO THE STATE. BY WEDNESDAY AFTERNOON... HIGHS WELL INTO THE 80S ARE EXPECTED WITH DEEP MIXING AND STRONG SOUTHERLY FLOW INTO THE STATE. WHILE SOME CONVECTION WILL OCCUR ON WEDNESDAY NIGHT...IT IS LIKELY THE BULK OF ANY PRECIPITATION WILL BE NORTHWEST OF THE FORECAST AREA CLOSER TO THE SURFACE BOUNDARY. THIS BOUNDARY WILL SAG INTO STATE ON THURSDAY WITH CONVECTION LIKELY TO BECOME WIDESPREAD BY AFTERNOON IN MOST LOCATIONS. A FEW SEVERE STORMS WILL ALSO BE POSSIBLE WITH THIS CONVECTION. THE STORMS ARE EXPECTED TO CONTINUE INTO THURSDAY NIGHT BUT WITH PROGRESSION TO THE EAST AS THE BOUNDARY SLIDES THROUGH THE STATE. SOME LINGERING PCPN IS FORECAST ON FRIDAY BEFORE ENDING WITH DRIER CONDITIONS INTO FRIDAY NIGHT. && .AVIATION...04/18Z ISSUED AT 1232 PM CDT SUN MAY 4 2014 BAND OF SHOWERS TIED TO UPPER LEVEL BOUNDARY EXITING FAR NORTHEAST IOWA. ANOTHER ROUND OF THETAE ADVECTION ARRIVES THIS EVENING AND OVERNIGHT...INTERACTING WITH THE BOUNDARY MAY CREATE ADDITIONAL LIGHT SHOWERS NORTH OVERNIGHT. OVERALL...CIGS TO REMAIN VFR AND WINDS TO REMAIN EASTERLY WITH LITTLE CHANGE IN THE NEXT 24 HOURS. SOUTHERN SITES WILL SEE LITTLE EXCEPT SOME PASSING MID LEVEL CLOUDS THROUGH 18Z MON. /REV && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...REV SHORT TERM...AWB LONG TERM...COGIL AVIATION...REV
AREA FORECAST DISCUSSION
NWS CARIBOU ME
507 PM EDT SUN MAY 4 2014 .SYNOPSIS... LOW PRESSURE WILL CONTINUE MOVING EAST TROUGH THE MARITIMES TONIGHT AND MONDAY. AN UPPER LEVEL TROUGH WILL REMAIN OVER THE AREA TUESDAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST ON WEDNESDAY. && .NEAR TERM /THROUGH MONDAY/... 500 PM UPDATE...ADJUSTED AREAL COVERAGE OF RAINFALL MORE ACROSS THE CENTRAL PORTION OF THE CWA AS EVIDENT BY THE LATEST RADAR LOOP. THIS IS ALSO SUPPORTED BY THE GRADIENT BETWEEN MAXES/MINS ON THE THETA E ANALYSIS. SOME HEAVIER RAINFALL CAN BE EXPECTED IN THIS AREA THROUGH THE EVENING HRS. LIGHTNING DETECTION SHOWED SOME STRIKES ACROSS THE DOWNEAST REGION SOUTH OF THE BANGOR AREA OVER THE LAST HR(20Z), BUT SINCE THEN ACTIVITY HAS DIMINISHED. THE LATEST LAPS SOUNDINGS SUPPORTED BY THE RAP SHOWED SOME INSTABILITY ESPECIALLY W/ELEVATED CAPES IN THIS REGION. KEPT THE MENTION OF TSTMS IN THERE THROUGH THE EVENING FOR THE DOWNEAST AND THE COAST. PREVIOUS DISCUSSION...SURFACE LOW PRESSURE ACCOMPANIED BY UPPER LEVEL LOW PRESSURE WILL MOVE ACROSS THE MAINE COAST THIS EVENING THEN EASTWARD ACROSS NOVA SCOTIA TONIGHT THEN INTO THE ATLANTIC MONDAY. AREA OF THUNDER APPROACHING FROM THE WEST SO WILL PUT IN AREA OF ISOLATED THUNDER ACROSS COASTAL AREAS INTO THE EARLY EVENING. FOR POPS HAVE BLENDED THE NAM12... GFS40...SREF AND ECMWF. FOR SUSTAINED WINDS HAVE USED THE MOSG25. MAXIMUM TEMPERATURE GENERATED FROM BIAS CORRECTED CONSENSUS ALL BASED ON LATEST VERIFICATION. FOR MINIMUM TEMPERATURE WILL USE THE SUPPER BLEND. QPF GRIDS GENERATED FROM A BLEND OF THE NAM12... GFS40 AND ECMWF. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... LLVL MOISTURE LEFT OVR FROM THE DEPARTING ERN MARITIMES SFC/UPPER LVL LOW PRES SYS WILL REMAIN MSLY IN THE FORM OF CLDNSS OVR THE N PTN OF THE FA...WITH ANY EVE SHWRS MSLY OVR THE NW. THERE MAY BE ENOUGH WRLY DOWNSLOPE FOR THE S HLF OF THE FA FOR PARTIAL CLRG LATE MON NGT. ANY CLRG FOR SRN PTNS OF THE FA WILL BE SHORT LIVED GOING INTO TUE AS AN E...W UPPER TROF N OF OUR REGION SWINGS SWRD INTO THE FA BY TUE AFTN...DESTABILIZING THE LOWER TO MID LAYERS OF THE ATMOSPHERE AND CAUSING SCT SHWRS BY MIDDAY ACROSS THE N...WHICH WILL WORK SWRD INTO SRN PTNS OF THE FA BY MID AFTN. OVERALL...BASIN WIDE 6 HRLY QPFS WILL BE LGT...LESS THAN 0.05 INCHES...WITH THIS FEATURE...BUT WE CANNOT RULE OUT LCLZD RNFL OF 0.10 TO 0.20 INCHES WITH ANY HEAVIER SHWRS TUE AFTN...SPCLY CNTRL AND INTERIOR DOWNEAST PTNS OF THE FA TUE AFTN. ONCE THIS UPPER TROF PIVOTS SE OF THE REGION TUE EVE...MORE GENERAL CLRG SHOULD OCCUR FOR ALL OF THE FA LATE TUE NGT... WITH WED LOOKING MUCH DRIER...WITH THE ONLY SLGT CHC OF AFTN SHWRS OVR ERN PTNS OF THE REGION AS A VERY WEAK S/WV ALF FROM CNTRL QB MOVES ESE OVR NRN/ERN PTNS OF THE FA. HIGH TEMPS TUE WILL BE BELOW SEASONAL AVGS FOR THIS TM OF SPRING DUE TO MORE CLD AND SHWR CVRG COMPARED TO WED...WHICH SHOULD SEE HI TEMPS RECOVERING TO NEAR NORMAL VALUES. OVRNGT LOWS BOTH MON NGT AND TUE NGT WILL MSLY BE ABV FZG FOR ALL OF THE REGION DUE TO CLD CVR AND SFC DWPTS FCST TO BE AOA FZG. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A HIGH PRESSURE RIDGE WILL BE CENTERED ACROSS THE REGION AT THE START OF THE PERIOD AND WILL REMAIN OVER THE AREA UNTIL MID DAY FRIDAY. A DEEPENING LOW OVER THE GREAT PLAINS WITH A WARM FRONT EXTENDING EAST INTO THE ERN GREAT LAKES AT THE START OF THE PERIOD... WILL CONTINUE TO DEEPEN AND MOVE NE INTO THE NRN GREAT LAKES REGION. BY FRIDAY AFTERNOON THE WARM FRONT WILL MOVE INTO THE SW COAST OF MAINE. BY SAT MRNG THE COLD FRONT MOVES INTO CENTRAL MAINE. BY SAT EVNG THE GFS AND ECMWF DIFFER A BIT ON THEIR SOLUTIONS. THE ECMWF MOVE THE COLD FRONT EAST OF MAINE AND BUILDS HIGHER PRESSURE INTO WRN MAINE. THE GFS MOVES A NEW LOW INTO THE SW COAST...SLOWING THE FORWARD MOVEMENT OF THE COLD FRONT...KEEPING IT ACROSS CENTRAL MAINE. THESE DIFFERENCES CONTINUE INTO SUN MRNG. THE GFS MOVES THE NEW LOW THROUGH MAINE...AND BEGINS TO BUILD HIGHER PRESSURE...THE ECMWF MOVES A NEW LOW INTO NRN NY...SHIFTS THE HIGH TO THE EAST...AND MOVES A WARM FRONT INTO THE SW COAST OF MAINE. THE GFS MAINTAINS THE HIGH PRESSURE RIDGE ACROSS MAINE SUN EVNG...WITH A NEW LOW PRESSURE SYSTEM EXTENDING N/S FROM WEST OF JAMES BAY TO ERN TX...WITH SEVERAL MINOR LOW ALONG THE BOUNDARY. THE ECMWF MOVES THE LOW INTO NRN NH/WRN ME BORDER WITH A WARM FRONT EXTENDING ACROSS TO THE SE COAST OF MAINE. BY THE END OF THE PERIOD THE GFS MOVES THE NEW FRONTAL BOUNDARY TO ERN NH/WRN ME...THE ECMWF MOVES THE LOW INTO THE CANADIAN MARITIMES...BUILDS HIGHER PRESSURE ACROSS MAINE. SO THE MODELS ARE IN GOOD AGREEMENT THROUGH THE MID PORTIONS OF THE EXTENDED...THEN THOUGH THE TIMING DIFFER...GENERALLY UNSETTLED CONDITIONS WILL PREVAIL FROM THE MID POINT THROUGH THE END OF THE PERIOD. LOADED THE SUPERBLEND THROUGH THE EXTENDED PERIOD. LOADED NAWAVE 4 FOR SEAS IN THE COASTAL WATERS...ADDED 15 PERCENT TO WINDS FOR GUSTS OVER LAND AND 30 PERCENT FOR GUSTS OVER THE COASTAL WATERS. && .AVIATION /21Z SUNDAY THROUGH FRIDAY/... NEAR TERM: EXPECT IFR/MVFR TONIGHT IMPROVING TO VFR MONDAY MORNING. SHORT TO LONG TERM: MSLY MVFR CLGS...AND ATTMS VSBYS WITH BKN-OVC SC CLD CVR AND OCNL SHWRS CAN BE XPCTD ACROSS ALL THE TAF SITES MON NGT THRU TUE...WITH CONDITIONS IMPROVING TO VFR TUE NGT. VFR CONDITIONS THEN SHOULD CONT WED THRU FRI. && .MARINE... NEAR TERM: HAVE BLENDED THE SREF AND THE GFS40 FOR SUSTAINED WINDS. FOR WAVES: CURRENT WNA/4 WIND TOO STRONG IN GULF OF MAINE SO HAVE USED THE SWAN/NAM TO POPULATE GRIDS. PRIMARY WAVE SYSTEM GENERATED IN SOUTHERLY FETCH FURTHER TO THE SOUTH 3 FEET/8 SECONDS... HOWEVER EXPECT THIS GROUP TO STAY BELOW SCA. FETCH DIRECTION SHIFTS OFF-SHORE EARLY MONDAY BUT WITH LIMITED FETCH DISTANCE WAVE HEIGHTS CLOSE TO COAST MINIMAL. SHORT TERM: NO HDLNS LOOK TO BE NEEDED FOR OUR MZS...WITH WINDS MSLY BLO 15 KTS...AND WVS MSLY BLO 3 FT OVR THE OUTER MZS050-051 AND 2 FT OVR THE INNER HARBOR/BAY MZ052. USED A MODEL/MOS BLEND FOR WINDS AND WENT WITH OR SLIGHTLY BLO WW3 WV GUIDANCE FOR WV HTS. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...NONE. && $$ NEAR TERM...HEWITT/MIGNONE SHORT TERM...VJN LONG TERM...NORTON AVIATION...HEWITT/MIGNONE/VJN MARINE...HEWITT/MIGNONE/VJN
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
541 PM CDT Sun May 4 2014 .SHORT TERM: (Through Late Tonight) Issued at 239 PM CDT Sun May 4 2014 Frontal boundary remains stalled along I-70 corridor. So main forecast issues in the short term are the winds and low temps for tonight. East winds to prevail north of front, while south winds to expected over southern MO and far southern IL. Some mid and high clouds north of front, but no precipitation expected as low and mid levels remain rather dry. Towards daybreak frontal boundary will begin to slowly move to the north as a warm front. As for low temps, will range from the upper 40s far north to the upper 50s over central and southern MO. Could see a pocket of colder temps over eastern Ozarks, so lowered temps a bit there. Byrd .LONG TERM: (Monday through Next Sunday) Issued at 239 PM CDT Sun May 4 2014 The main issue for at least the next several days will be the location of the east-west quasi-stationary front and resultant impact on temperatures. Guidance is good agreement moving the boundary northward on Monday morning to around a Moberly-Matoon line by early afternoon. While there will be a few more clouds around on Monday, the character of the air mass and low level flow regime is not expected to change. Thus it appears highs in the 80s to lower 90s will be the norm within the warm sector, and in the 70s to the north of the front. The front then sags south again on Monday night as surface high pressure builds southeastward from the Great Lakes region. This southward position doesn`t appear to last long however as the front is forecast to retreat northward again on Tuesday, draped across northern MO into central IL by late afternoon and exiting the CWA by late evening. This northward retreat is in response to falling pressures across the Plains and the movement of an initial low pressure wave into eastern Nebraska. The entire region will be well within the warm sector on Wednesday with highs area-wide in the 80s. The models have been overforecasting the surface dew points recently and this trend will persist for the next several days as high pressure in the northern Gulf is inhibiting southerly return flow. The combination of warm temps aloft and limited low level moisture will result in an air mass capped to surface-based convection through Wednesday. I think Wednesday night will remain quiet and mild with a general increase in clouds. Things begin to change on Thursday with shower and thunderstorm chances ramping up, especially Thursday night into Friday. We should see a more robust return of low level moisture as the Gulf opens up, and the western U.S. upper trof ejects northeastward across the Rockies and Plains into the upper MS valley sending a cold front into the area Thursday night. This front will temporarily stall across portions of southern MO and southern IL late Friday into Friday night, before lifting back northward on Saturday. Glass && .AVIATION: (For the 00z TAFs through 00z Monday Evening) Issued at 431 PM CDT Sun May 4 2014 VFR through the period with occasional mid and high clouds. The primary forecast issue is the prevailing wind direction because a stalled frontal boundary will continue to waver across the region over the next few days. Winds will be easterly on the north side of the front, lgt/var along the front, and southerly to southwesterly on the south side of the front. Precipitation is very unlikely due to strong capping and lack of moisture. Local WRF and RAP forecasts in BUFKIT both show strong southwest winds above KCOU tonight at around 1000 ft during a time when surface winds should be from the south. Local WRF and RAP models also show fairly strong winds above KUIN at around 1000 ft, but the winds are more unidirectional with height through that layer compared to winds at KCOU. LLWS has been added to the TAFs for KCOU and KUIN. Specifics for KSTL: VFR through the period with occasional mid and high clouds. The prevailing wind direction will depend on the location of a quasistationary frontal boundary (easterly winds on the north side of the front and south to southwest winds on the south side of the front). Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
128 PM CDT SUN MAY 4 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 AS ADVERTISED BY THE NAM...STRONG MIDLEVEL FRONTOGENESIS HAS SPAWNED AN AREA OF SHOWERS AND THUNDERSTORMS ACROSS SD THIS MORNING. THE RAP SHOWS THIS FORCING MECHANISM MOVING QUICKLY EAST AWAY FROM THE FCST AREA BY 12Z THIS MORNING AND THIS IS CONSISTENT WITH THE LATEST RADAR TRENDS. THE RAP AND NAM GENERATE A FEW HUNDRED JOULES OF ELEVATED INSTABILITY THIS AFTN ACROSS PINE RIDGE SUGGESTING THE POTENTIAL FOR ISOLATED TSTM DEVELOPMENT. THE FORECAST IS DRY AS NEITHER MODEL IS GENERATING AND QPF IN THAT AREA. THE TEMPERATURE FORECAST TODAY HAS HIGHS RANGING FROM THE 60S NORTH TO UPPER 80S IN THE FAR SOUTHWEST. THE CANADIAN HIGH PRESSURE SYSTEM WILL CONTINUE TO RIDGE THRU MUCH OF THE FCST AREA TODAY SUPPORTING THIS TEMPERATURE FORECAST WHICH IS CONSISTENT WITH THE 07Z RUN OF THE RAP. ALL MODELS EXCEPT THE GEM SUGGEST THE POTENTIAL FOR STRATUS DEVELOPMENT TONIGHT BUT THE NAM AND ECM ONLY SHOW 85 PERCENT RH IN THE 500M AGL LEVEL VS THE GFS AROUND 98 PERCENT. THE BEST APPROACH AT THIS TIME WOULD BE TO WAIT FOR LATER MODEL DATA. A SMALL PATCH OF STRATUS HAS WORKED INTO PINE RIDGE THIS MORNING WHICH SHOULD BURN OFF BY NOON TIME ACCORDING TO THE RAP MODEL. LOWS TONIGHT FALL INTO THE 40S. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MONDAY BEGINS WITH A BROAD RIDGE ACROSS MOST OF THE CONUS...WITH A TROUGH DIGGING INTO THE PAC NW AND ONE OFF THE NEW ENGLAND COAST. AT THE SFC A LEE SIDE TROUGH MEANDERS ACROSS THE FRONT RANGE FROM A LOW IN S CENTRAL CANADA TO A LOW IN KANSAS. DURING THE AFTERNOON SUNNY SKIES WILL MIX MID AND UPPER TEENS 850 MB TEMPS AND HIGHS IN THE 70S AND LOWER 80S. OVERNIGHT AN UPPER LEVEL DISTURBANCE WILL RIDE THE RIDGE ACROSS THE DAKOTAS. THIS WILL COMBINE WITH A LL JET TO PRODUCE SOME SHOWERS AND A FEW THUNDERSTORMS. MAJORITY OF THE ACTIVITY TO THE NORTH...HOWEVER THE NAM AND THE GFS SUPPORT SOME BUILDING SOUTH WHERE THERE IS SLIGHTLY BETTER MOISTURE. THE MOISTURE IS ONLY SLIGHTLY BETTER AND HAVE CONCERNS THE ACTIVITY WILL NOT DEVELOP THIS FAR SOUTH...AWAY FROM THE MAIN DISTURBANCE. MILD LOWS EXPECTED IN THE UPPER 40S TO AROUND 50. TUESDAY THE UPPER LEVEL TROUGH DIGS TOWARDS THE DESERT SOUTHWEST WITH THE RIDGE TO AMPLIFY OVER THE MISS RVR VALLEY. THIS WILL BEGIN THE TRANSITION TO MORE SW FLOW OVER THE HIGH PLAINS. TUESDAY STILL LOOKS DRY...THEN ANOTHER DISTURBANCE TO PUSH ACROSS THE AREA TUESDAY EVENING. MODELS INITIATE ACTIVITY TO THE WEST...WHICH SHOULD THEN PUSH NE ACROSS THE AREA. DRY AIR WILL BE TOUGH TO OVERCOME...ESPECIALLY IN THE SW...SO POPS CONFINED TO THE NW ZONES TUESDAY NIGHT. BY WEDNESDAY AND THURSDAY THE UPPER LEVEL TROUGH WILL BE CROSSING THE CENTRAL ROCKIES WHILE A COLD FRONT DRIFTS IN FROM THE NW. MEANWHILE SFC LOW STRENGTHEN OVER E CENTRAL COLORADO. THE LOW WILL THEN LIFT NE ACROSS NEB. TIMING STILL OFF A LITTLE BETWEEN THE MODELS...AND THE SLOWER GFS AND GEM HAVE A MORE PRONOUNCED DRY SLOT INTO SW AND S CENTRAL NEB. ANOTHER CONCERN IS THURSDAY NIGHT AS THE SYSTEM PUSHES EAST. THE EC DRAWS DOWN SOME COOLER AIR INTO FAR NW NEB...COLD ENOUGH FOR POSSIBLY A MIX. CURRENT THOUGH IS THE TEMPS TO NOT FALL FAST ENOUGH INTO THE MID 30S FOR ANY MIX AT THIS POINT AND NO MENTION OF SNOW. THE CLOUDS AND COOLER AIR BEHIND THE FRONT WILL RESULT IN 60S AND 70S ON WED AND 50S AND 60S FOR THURS. BY FRIDAY THE SYSTEM IS EAST WITH SLIGHT RIDGING OVER THE WEST. 850 MB TEMPS SLOWLY REBOUND AND A WARM UP IS EXPECTED. AFTER 60S ON FRIDAY...MORE 70S ARE FORECAST FOR SATURDAY. A LOW WILL PUSH ACROSS THE DAKOTAS IN THE ZONAL TO NW WEST FLOW. MOISTURE IS LIMITED TO BASICALLY THE PACIFIC AND WILL KEEP FORECAST DRY FOR NOW. WILL MONITOR AS WE MAY NEED TO ADD SOME ISOLATED SPRINKLES OR LIGHT SHOWERS IN THE COMING DAYS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 118 PM CDT SUN MAY 4 2014 A NEARLY STATIONARY FRONT WILL REMAIN ACROSS NORTHERN KANSAS...WESTWARD INTO NORTHEAST COLORADO THROUGH TONIGHT. PERSISTENT EAST TO SOUTHEAST WINDS TO THE NORTH OF THE FRONT WILL SLOWLY ADVECT MOISTER AIR WEST INTO SOUTHWEST AND WESTERN NEBRASKA. AS MOISTURE POOLS TONIGHT TO THE NORTH OF THE FRONT...SOME STRATUS MAY DEVELOP BY 12Z MONDAY MORNING ACROSS CENTRAL AND SOUTHWEST NEBRASKA. HAVE INTRODUCED A SCATTERED DECK AT 1000FT AT KLBF TO HINT AT THE POSSIBILITY OF STRATUS. MODELS ARE GIVING MIXED SIGNALS REGARDING THE EXTENT OF THE STRATUS...SO WASN/T CONFIDENT ENOUGH TO GO WITH A BROKEN OR OVERCAST CEILING AT THIS POINT. OUTSIDE OF ANY STRATUS DEVELOPMENT...EXPECT VFR CONDITIONS WITH SCATTERED TO BROKEN MID AND HIGH LEVEL CLOUDS. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...TAYLOR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
544 PM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 544 PM CDT SUN MAY 4 2014 PRECIPITATION CONTINUES TO MOVE QUICKLY EAST ACROSS NORTHWEST AND NORTH CENTRAL NORTH DAKOTA. LOOKS LIKE PREVIOUS FORECAST HAD A GOOD HANDLE ON POPS BASED ON HRRR/RAP OUTPUT. ONLY SOME MINOR TWEAKS TO POPS BASED ON LATEST RADAR. DID UPDATE TEMPERATURES WITH LOWER 30S ACROSS THE FAR NORTHWEST AND NORTH CENTRAL. HERE WILL LIKELY SEE ALL SNOW. WEATHER CAMERAS FROM RAY...PORTAL AND CARPIO INDICATE LIGHT ACCUMULATIONS ON GRASSY SURFACES. HEAVIEST PRECIPITATION AMOUNTS THROUGH EARLY EVENING LOOK WILL BE OVER THE FAR NORTH CENTRAL...ALONG THE CANADIAN BORDER. AS YOU MOVE FARTHER EAST INTO THE BOTTINEAU...ROLLA AND RUGBY AREAS...PREVIOUS INSOLATION HAS PUSHED TEMPERATURES INTO THE LOW TO MID 40S SO WE WILL LIKELY SEE A LITTLE RAIN BEFORE PRECIPITATION CHANGES TO SNOW. WITH THE BACK EDGE ALREADY MOVING INTO THE FAR NORTHWEST...THINK 1 TO 2 INCHES ON GRASSY SURFACES WILL BE THE EXTENT TO ANY ACCUMULATIONS. WILL SEND UPDATED TEXT PRODUCTS SHORTLY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 339 PM CDT SUN MAY 4 2014 SNOWFALL POTENTIAL LATE THIS AFTERNOON AND EVENING WILL HIGHLIGHT THE SHORT TERM FORECAST. WILL FOLLOW CLOSELY TO THE 18 UTC RAP/HRRR WHOSE PREVIOUS RUNS HAVE HAD A GOOD HANDLE ON THE PRECIPITATION EXTENT AND TYPE ACROSS NORTHEAST MONTANA AND INTO FAR NORTHWEST NORTH DAKOTA THIS AFTERNOON. AS OF 20 UTC...SNOW IS BEING REPORTED FROM ESTEVAN AND CROSBY THROUGH TIOGA. AS LIFTING INCREASES ACROSS NORTHWEST AND FAR NORTH CENTRAL NORTH DAKOTA LATE THIS AFTERNOON AND EARLY EVENING...AND AIDED BY DECREASING INSOLATION...RAIN IS EXPECTED TO MIX WITH OR CHANGE TO ALL SNOW AS SURFACE TEMPERATURES DROP INTO THE 32-35 F RANGE WHICH IS CURRENTLY SUPPORTING SNOW. ONE TO TWO INCHES OF SNOW IS POSSIBLE FOR US HIGHWAY 2 AND POINTS NORTH...MOSTLY ON GRASSY SURFACES...WITH PERHAPS UP TO THREE INCHES ACROSS DIVIDE COUNTY WHICH THE RAP HAS CONSISTENTLY HIGHLIGHTED FOR THE GREATEST TOTALS IN NORTH DAKOTA. FOR NOW...HAVE AN SPS OUT TO COVER THE THREAT AND WILL MONITOR CONDITIONS CLOSELY SHOULD A WINTER WEATHER ADVISORY BECOME NECESSARY. THE PRECIPITATION BAND IS EXPECTED TO BECOME FOCUSED PRIMARILY ACROSS NORTHEAST NORTH DAKOTA AND NORTHWEST MINNESOTA AFTER 06 UTC. FOR MONDAY...A WARMER DAY IS EXPECTED WITH PLENTIFUL INSOLATION AND LOW LEVEL WARM AIR ADVECTION AHEAD OF A LEE SURFACE TROUGH WITH WIDESPREAD HIGHS IN THE 60S. DID MAINTAIN SLIGHT CHANCE POPS FOR THUNDERSTORMS GENERALLY WEST OF HIGHWAY 83 MONDAY AFTERNOON WITH 200-400 J/KG OF ML CAPE FORECAST WITH WEAK IMPULSES CRESTING THE BROAD UPPER LEVEL RIDGE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 339 PM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH THE UPCOMING WEEK. BY MONDAY NIGHT A LARGE-SCALE LONGWAVE TROUGH IS FORECAST TO HAVE SET UP OVER THE WEST COAST...AND EMERGE INTO THE CENTRAL PART OF NORTH AMERICA BY THURSDAY- EXTENDING FROM NORTH CENTRAL CANADA TO THE SOUTHERN US PLAINS. THIS WILL BRING A PERIOD OF GOOD CHANCES OF SHOWERS AND THUNDERSTORMS TO THE REGION...WITH CHANCES OF RAIN EACH DAY AND NIGHT THROUGH THURSDAY. TOTAL RAINFALL ESTIMATES DURING THE MONDAY NIGHT THROUGH THURSDAY PERIOD RANGE FROM 1/4 INCH TO 1 1/4 INCHES OVER A WIDESPREAD AREA OF WESTERN AND CENTRAL NORTH DAKOTA. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. BY FRIDAY A SEMI-PERMANENT LOW OVER NORTH CENTRAL CANADA REMAINS IN PLACE...AS THE SOUTHERN EXTENSION OF THE LARGE-SCALE TROUGH LIFTS NORTHEASTWARD THROUGH THE GREAT LAKES TOWARDS HUDSON BAY. THIS WILL LOWER THE CHANCES OF SHOWERS TO THE FORECAST AREA...AND ALLOW TEMPERATURES TO CLIMB BACK INTO THE 60S ON FRIDAY. THE CHANCES OF SHOWERS RETURN ON SATURDAY AS THE NEXT UPPER LEVEL SHORTWAVE IS FORECAST TO MOVE EAST ACROSS THE NORTHERN US ROCKIES AND INTO THE NORTH CENTRAL STATES. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 544 PM CDT SUN MAY 4 2014 CONDITIONS AT KISN AND KMOT WILL REMAIN IN MVFR/IFR IN STRATUS WITH RAIN AND SNOW THROUGH EARLY EVENING. ELSEWHERE...VFR CONDITIONS ARE FORECAST FOR THE 00 UTC TAF CYCLE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...AYD LONG TERM...JV AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
339 PM CDT SUN MAY 4 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 339 PM CDT SUN MAY 4 2014 SNOWFALL POTENTIAL LATE THIS AFTERNOON AND EVENING WILL HIGHLIGHT THE SHORT TERM FORECAST. WILL FOLLOW CLOSELY TO THE 18 UTC RAP/HRRR WHOSE PREVIOUS RUNS HAVE HAD A GOOD HANDLE ON THE PRECIPITATION EXTENT AND TYPE ACROSS NORTHEAST MONTANA AND INTO FAR NORTHWEST NORTH DAKOTA THIS AFTERNOON. AS OF 20 UTC...SNOW IS BEING REPORTED FROM ESTEVAN AND CROSBY THROUGH TIOGA. AS LIFTING INCREASES ACROSS NORTHWEST AND FAR NORTH CENTRAL NORTH DAKOTA LATE THIS AFTERNOON AND EARLY EVENING...AND AIDED BY DECREASING INSOLATION...RAIN IS EXPECTED TO MIX WITH OR CHANGE TO ALL SNOW AS SURFACE TEMPERATURES DROP INTO THE 32-35 F RANGE WHICH IS CURRENTLY SUPPORTING SNOW. ONE TO TWO INCHES OF SNOW IS POSSIBLE FOR US HIGHWAY 2 AND POINTS NORTH...MOSTLY ON GRASSY SURFACES...WITH PERHAPS UP TO THREE INCHES ACROSS DIVIDE COUNTY WHICH THE RAP HAS CONSISTENTLY HIGHLIGHTED FOR THE GREATEST TOTALS IN NORTH DAKOTA. FOR NOW...HAVE AN SPS OUT TO COVER THE THREAT AND WILL MONITOR CONDITIONS CLOSELY SHOULD A WINTER WEATHER ADVISORY BECOME NECESSARY. THE PRECIPITATION BAND IS EXPECTED TO BECOME FOCUSED PRIMARILY ACROSS NORTHEAST NORTH DAKOTA AND NORTHWEST MINNESOTA AFTER 06 UTC. FOR MONDAY...A WARMER DAY IS EXPECTED WITH PLENTIFUL INSOLATION AND LOW LEVEL WARM AIR ADVECTION AHEAD OF A LEE SURFACE TROUGH WITH WIDESPREAD HIGHS IN THE 60S. DID MAINTAIN SLIGHT CHANCE POPS FOR THUNDERSTORMS GENERALLY WEST OF HIGHWAY 83 MONDAY AFTERNOON WITH 200-400 J/KG OF ML CAPE FORECAST WITH WEAK IMPULSES CRESTING THE BROAD UPPER LEVEL RIDGE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 339 PM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH THE UPCOMING WEEK. BY MONDAY NIGHT A LARGE-SCALE LONGWAVE TROUGH IS FORECAST TO HAVE SET UP OVER THE WEST COAST...AND EMERGE INTO THE CENTRAL PART OF NORTH AMERICA BY THURSDAY- EXTENDING FROM NORTH CENTRAL CANADA TO THE SOUTHERN US PLAINS. THIS WILL BRING A PERIOD OF GOOD CHANCES OF SHOWERS AND THUNDERSTORMS TO THE REGION...WITH CHANCES OF RAIN EACH DAY AND NIGHT THROUGH THURSDAY. TOTAL RAINFALL ESTIMATES DURING THE MONDAY NIGHT THROUGH THURSDAY PERIOD RANGE FROM 1/4 INCH TO 1 1/4 INCHES OVER A WIDESPREAD AREA OF WESTERN AND CENTRAL NORTH DAKOTA. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. BY FRIDAY A SEMI-PERMANENT LOW OVER NORTH CENTRAL CANADA REMAINS IN PLACE...AS THE SOUTHERN EXTENSION OF THE LARGE-SCALE TROUGH LIFTS NORTHEASTWARD THROUGH THE GREAT LAKES TOWARDS HUDSON BAY. THIS WILL LOWER THE CHANCES OF SHOWERS TO THE FORECAST AREA...AND ALLOW TEMPERATURES TO CLIMB BACK INTO THE 60S ON FRIDAY. THE CHANCES OF SHOWERS RETURN ON SATURDAY AS THE NEXT UPPER LEVEL SHORTWAVE IS FORECAST TO MOVE EAST ACROSS THE NORTHERN US ROCKIES AND INTO THE NORTH CENTRAL STATES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 339 PM CDT SUN MAY 4 2014 CONDITIONS AT KISN AND KMOT WILL TREND TOWARDS MVFR/IFR IN STRATUS AND RAIN MIXING WITH SNOW LATE THIS AFTERNOON AND EVENING. ELSEWHERE...VFR CONDITIONS ARE FORECAST FOR THE 18 UTC TAF CYCLE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AYD LONG TERM...JV AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
319 PM CDT SUN MAY 4 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 318 PM CDT SUN MAY 4 2014 LATEST RADAR IMAGE FROM KMBX (MINOT...ND) IS SHOWING MID LEVEL MOISTURE CURRENTLY SPREADING ACROSS SOURIS RIVER BASIN...HOWEVER GROUND TRUTH AS FAR AS PRECIP REPORTS IS FURTHER WEST...ROUGHLY ALONG A WILLISTON TO ESTEVAN (SASK) LINE. HAVE BEEN GOING WITH A RUC/NAM SOLUTION...PRIMARILY USING RUC AS GUIDANCE THROUGH 09Z THEN TRENDING TOWARD NAM FOR MONDAY. TONIGHT...A VORT MAX EMBEDDED IN ZONAL UPPER LEVEL FLOR...CURRENTLY OVER NORTHWESTERN ND...WILL MOVE ACROSS THE STATE AND INTO W CNTRL MN TONIGHT. WEAK ADIABATIC OMEGA AND H700 FG FORCING WILL PROVIDE SOME FORCING TO GENERATE SHOWERS AS THE VORT MAX MOVES ACROSS THE STATE. CIGS HAVE DROPPED DOWN TO 4K FT IN PORTIONS OF NW ND...GIVING MORE CONFIDENCE RAIN WILL MAKE IT TO THE SFC. OVERALL...HOWEVER...MODELS APPEAR A BIT BULLISH ON MOISTURE AND EXPECTING ONLY TEN TO TWENTY HUNDREDTHS OVER DVL BASIN. DO HAVE CATEGORICAL POPS OVER THIS REGION WITH LIKELIES IN THE NORTH CENTRAL VALLEY...TAPERING OFF TO HIGH CHANCE POPS AS ACTIVITY GETS TO THE EASTERN ZONES...MAINLY DUE TO LESS CONFIDENCE ON TIMING. BY 12Z...NAM SHOWING DOWNWARD VERTICAL MOTION ACROSS MAJORITY OF AREA AND DRYING THINGS UP SHORTLY AFT 12Z. AGAIN...HAVE USED RUC AS GUIDANCE FOR HOURLY POPS THROUGH 09Z WITH NAM FOR THE 09Z TO 12Z TIMEFRAME...THEN DRY ON MONDAY. ONE CAVEAT...RUC DOES HOLD ON TO SHOWERS IN THE NORTHWESTERN ZONES...AND TRENDED TOWARD A DRIER SOLUTION IN THIS AREA (MORE IN LINE WITH NAM). OVERNIGHT LOWS IN THE NORTHWEST AND NORTHEAST WILL BE IN THE LOWER 30S AND DID MENTION SNOW FOR THESE AREAS BUT NO ACCUMULATION EXPECTED IF THERE IS A CHANGE OVER BEFORE SHOWERS MOVE OUT OF AREA. MONDAY AND MONDAY NIGHT...BROAD WEAK RIDGING ALOFT WILL KEEP MONDAY DRY. RETURN FLOW WILL INCREASE THROUGHOUT THE DAY AND INCREASED SOLAR WILL ALLOW TEMP TO CLING INTO THE MID 50S TO MID 60S...WITH WARMEST TEMPS ACROSS SOUTHEASTERN ND. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 318 PM CDT SUN MAY 4 2014 MONDAY NIGHT THROUGH TUESDAY NIGHT...UPPER RIDGE WILL SHIFT EAST AND SW FLOW PATTERN WILL SET UP ALOFT...WITH A WAVE DEVELOPING AND EJECTING OUT OF CNTRL ROCKIES EARLY TUES MORNING. PRECIP WILL DEVELOP OVER WRN DAKOTAS TUE MORNING. SFC LOW OVER SOUTHERN PLAINS WILL STRENGTHEN AND HELP PUMP GULF MOISTURE UP INTO EASTERN DAKOTAS. 12Z GFS SHOWING INCREASING H850 MOISTURE FLUX INTO CNTRL DAKOTAS...WITH PWATS REACHING AROUND ONE INCH BY 18Z. GFS ALSO SHOWS BAND OF MID LEVEL FRONTOGENESIS FORMING MID DAY TUESDAY. WILL KEEP INHERITED LIKELIES IN FOR TUESDAY. ECMWF AND GFS IN DECENT AGREEMENT WITH MOST PRECIP FALLING ALONG AND NORTH OF HIGHWAY 200 CORRIDOR...WITH NAM FOCUSING ON DVL BASIN...WHICH IS WHERE I WILL LIMIT LIKELIES FOR TUE AFTN. CURRENT QPF VALUES APPROACHING ONE HALF INCH FOR PORTIONS OF N CNTRL ND...BUT PLENTY OF TIME TO WORK OUT THOSE DETAILS. WED...INVERTED TROUGH SHIFTS OFF TO EAST DURING DAY WED...WITH NORTH TO NORTHEAST FLOW SETTING UP. SHOULD SEE PORTIONS OF THE NORTHWESTERN CWA DRY UP...HOWEVER MODELS ALL OVER THE PLACE WITH MOISTURE FOR WEDNESDAY. GENERALLY LIKE THE GFS SOLUTION OF DRYING OUT THE DVL LAKE BASIN...BUT THE ECMWF CONTINUES RATHER BULLISH MOISTURE OVER THE AREA AND EVEN THE NAM SHOWS SOME POPS OVER THE AREA. INHERITED CHANCE POPS THEREFORE SEEMS REASONABLE...SUPPORTED BY CONSALL..AND NOT ENOUGH CONFIDENCE AT THIS POINT TO TRY AND TIME CLEARING FOR WED AFTN. WED NIGHT THROUGH SUNDAY...ACTIVE ZONAL/SW FLOW ALOFT DEPICTED BY ALL THE MODELS. THE MAIN CHALLENGE WILL BE TIMING OF INDIVIDUAL WAVES WITHIN THIS FLOW. THE BEST CONSENSUS FOR HIGHER SHOWER CHANCES APPEARS TO BE WED NIGHT INTO THUR NIGHT...AND THEN AGAIN ON SATURDAY. DURING THIS ENTIRE PERIOD...IT APPEARS THAT 1-2 INCHES OF RAINFALL IS PROBABLE. TEMPERATURES WILL BE DEPENDENT ON CLOUDS COVER AND ACTUAL TIMING OF SHOWERS...BUT GENERALLY NEAR OR SLIGHTLY BELOW NORMAL VALUES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 108 PM CDT SUN MAY 4 2014 MAINLY VFR TODAY AND TONIGHT. HIGH AND MID LEVEL MOISTURE WILL CONTINUE TO INCREASE TODAY FROM WEST TO EAST. A BAND OF RAIN SHOWERS WILL OCCUR TONIGHT...ESPECIALLY NEAR THE HIGHWAY TWO CORRIDOR. A BRIEF PERIOD OF MVFR CIGS WILL BE POSSIBLE DURING THE RAINFALL...BUT THE PROBABILITY FOR THESE CIGS IS LOW AT THIS POINT. WINDS ARE EXPECTED TO BECOME EAST/SOUTHEAST...BELOW 12 KNOTS. && .HYDROLOGY... ISSUED AT 108 PM CDT SAT MAY 3 2014 TRIBUTARIES INTO THE MAINSTEM RED CONTINUE TO SEE FALLING STAGES. THE RED RIVER AT FARGO IS FORECAST TO FALL BELOW MODERATE FLOOD STAGE OVERNIGHT TONIGHT. FARTHER NORTH...A BROAD FLAT CREST HAS OCCURRED ACROSS CENTRAL INTO NORTHERN SECTIONS OF THE RED. A VERY GRADUAL RECESSION IN STAGES IS FORECAST FROM EAST GRAND FORKS TO OSLO...WITH SOME GRADUAL RISES ANTICIPATED TO CONTINUE FROM DRAYTON NORTHWARD TO PEMBINA BELOW FLOOD STAGE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...SPEICHER LONG TERM...TG/SPEICHER AVIATION...TG HYDROLOGY...MAKOWSKI
AREA FORECAST DISCUSSION
NWS BISMARCK ND
147 PM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 146 PM CDT SUN MAY 4 2014 THE HIGHLIGHT OF THE NEAR TERM CONTINUES TO BE SNOWFALL POTENTIAL ACROSS THE NORTHWEST AND NORTH CENTRAL LATE THIS AFTERNOON AND EVENING. AS OF 1845 UTC...A BAND OF LIGHT TO MODERATE PRECIPITATION WAS IN PLACE ACROSS NORTHEAST MONTANA. BASED UPON DUAL POL SIGNATURES AND SURFACE OBSERVATIONS...MOSTLY RAIN APPEARS TO BE FALLING FROM PLENTYWOOD...TO GLASGOW AND SOUTH WITH SNOW TO THE NORTH. THIS IS IN LINE WITH THE 15 UTC RAP/HRRR. THUS WILL FOLLOW THEIR SOLUTIONS FOR POPS AND PRECIPITATION TYPE AS THE BAND PROPAGATES INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA WHERE TEMPERATURES ARE IN THE 35-40F RANGE. THUS...EXPECT RAIN TO MIX WITH SNOW OR BECOME ALL SNOW AT TIMES NORTHWEST AND NORTH CENTRAL LATE THIS AFTERNOON AND EVENING. THE BIGGEST UNCERTAINTY IS IN HOW WELL SNOW MAY ACCUMULATE. AT THIS TIME...ONE TO TWO INCHES MAY ACCUMULATE ON GRASSY SURFACES FOLLOWING THE RAP SNOWFALL FORECAST. ISSUED AN SPS FOR THE NORTHWEST AND NORTH CENTRAL TO DESCRIBE THE THREAT. UPDATE ISSUED AT 951 AM CDT SUN MAY 4 2014 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE FOR THE REMAINDER OF THE MORNING AND EARLY AFTERNOON. THE BIGGEST QUESTION IS SNOWFALL POTENTIAL THIS EVENING AND TONIGHT ALONG AND NORTH OF US HIGHWAY 2...WHERE THE INCOMING 12 UTC DETERMINISTIC GUIDANCE CONTINUES THE TREND OF THE 06 UTC SUITE OF THE POTENTIAL FOR ONE TO THREE INCHES OF SNOW. SURFACE TEMPERATURES WILL BE CRITICAL FOR PRECIPITATION TYPE...AND AFTERNOON WARMING WILL HAVE TO BE CLOSELY MONITORED TO DETERMINE THE TIMING OF CHANGE OVER TO SNOW. UPDATE ISSUED AT 612 AM CDT SUN MAY 4 2014 EARLY MORNING UPDATE FOR MINOR CHANGES TO TEMPERATURE TRENDS AND POPS. A NARROW BAND OF LIGHT SNOW AND MIXED PRECIPITATION CONTINUES FROM THE DICKINSON AREA...THROUGH MORTON COUNTY...INTO THE JAMES RIVER VALLEY. ANY ACCUMULATIONS OF GRASSY AREAS SHOULD MELT QUICKLY TODAY. ADDITIONAL PRECIPITATION EXPECTED TO MOVE INTO NORTHWEST ND AROUND MIDDAY AND CONTINUE PUSHING EAST THROUGH THE AFTERNOON. TEMPS EXPECTED TO BE WARM ENOUGH FOR ALL RAIN THERE...ALTHOUGH THAT WOULD NOT BE THE CASE GIVEN THE 06Z NAM WHICH INDICATES MORE QPF THIS MORNING. WILL PASS CONCERNS ALONG TO THE DAY SHIFT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT SUN MAY 4 2014 LATEST WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL LOW OFF THE WASHINGTON COAST WITH ADDITIONAL SHORTWAVES FARTHER UPSTREAM YET TO ROUND THE BASE OF THE TROUGH. A COUPLE OF SHORTWAVES WILL PEEL OFF THE MAIN UPPER LOW/TROUGH AND EJECT INTO NORTH DAKOTA THROUGH THE SHORT TERM PERIOD. FOR THE NEAR TERM/EARLY THIS MORNING...MONITORING THE NARROW BANDS OF PRECIPITATION ON THE BOWMAN AND BISMARCK RADARS. NOTHING SIGNIFICANT ON AMOUNTS VIA SURFACE REPORTS OR WEB CAMS...BUT AMOUNTS MAY BE FALLING IN BETWEEN ABOVE MENTIONED DATA POINTS. LATEST HRRR AND RAP BOTH LIFT THE NARROW BAND OF PRECIPITATION WEAKLY TO THE NORTHEAST THROUGH THE MORNING. THE ECMWF KEEPS THE BRUNT OF THE PRECIPITATION AMOUNTS IN THE FAR SOUTH...WHILE THE NAM/GFS SHOW A NARROW SWATH OF DECENT QPF WEST INTO SOUTH CENTRAL. WILL CONTINUE WITH A CHANCE TO LIKELY POPS MENTIONING SNOW/RAIN THROUGH MID MORNING BEFORE TRENDING DOWNWARD. LATER TODAY...CONSENSUS IS FOR THE NEXT SHORTWAVE TO MOVE FROM THE CENTRAL IDAHO PANHANDLE INTO NORTHERN NORTH DAKOTA BETWEEN 18Z SUNDAY AND 06Z MONDAY. THIS WILL RESULT IN CATEGORICAL POPS FOR THE NORTH DURING THIS TIME AND A CHANCE OF SHOWERS ELSEWHERE. TOWARD 00Z MONDAY...WEAK INSTABILITY PUSHES CLOSE TO OUR SOUTHWEST BORDER AND HAVE MAINTAINED A SLIGHT CHANCE FOR THUNDERSTORMS IN THE SOUTHWEST SUNDAY NIGHT. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 330 AM CDT SUN MAY 4 2014 MAIN FORECAST ISSUES IN THE LONG TERM PERIOD INCLUDE PRECIPITATION TRENDS/COVERAGE/AMOUNTS THROUGH AT LEAST MID WEEK. MEDIUM RANGE MODELS ARE STARTING TO COAL ESE AROUND A SIMILAR PROGRESSION OF A LARGE WESTERN CONUS TROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE EXPECTED TO INCREASE IN COVERAGE MONDAY NIGHT...WITH PERIODS OF SHOWERS AND ISOLATED CONVECTION CONTINUING THROUGH WEDNESDAY NIGHT BEFORE TAPERING OFF THURSDAY. CONSENSUS QPF AMONGST THE GFS/ECMWF/GEM NOW SUPPORTS WIDESPREAD TOTAL RAINFALL OF 0.33 TO 1 INCH...LESS BULLISH THAN PREVIOUS DAYS. RENEWED RISES ON AREAS RIVERS ARE POSSIBLE...THESE TYPE OF AMOUNTS WOULD NOT CAUSE ANY SIGNIFICANT FLOODING ISSUES. ABUNDANT CLOUD COVER WILL HELP SUPPRESS TEMPS AND INSTABILITY...SO THE OVERALL SEVERE WEATHER THREAT THROUGH THE PERIOD IS LOW. ANOTHER STORM SYSTEM COULD BRING ADDITIONAL SHOWERS TO THE FORECAST AREA ON SATURDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 146 PM CDT SUN MAY 4 2014 CONDITIONS AT KISN AND KMOT WILL TREND TOWARDS MVFR/IFR IN STRATUS AND RAIN MIXING WITH SNOW LATE THIS AFTERNOON AND EVENING. ELSEWHERE...VFR CONDITIONS ARE FORECAST FOR THE 18 UTC TAF CYCLE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
108 PM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 108 PM CDT SUN MAY 4 2014 NO CHANGES TO PUBLISHED GRIDS AT THIS TIME. 18Z DISCUSSION INCLUDED UPDATED AVIATION AND HYDRO SECTIONS BELOW. UPDATE ISSUED AT 1002 AM CDT SUN MAY 4 2014 LATEST RUC AND NAM FOCUSING ON A VORT MAX MOVING ACROSS MAINLY THE NORTHERN HALF OF THE CWA THIS EVENING AND TONIGHT...WITH BEST CHANCES FOR PRECIP MAINLY NORTH OF THE I 94 CORRIDOR. WILL USE NAM GUIDANCE THROUGH ABOUT 09Z AND THEN NAM GUIDANCE THROUGH 12Z. SHOULD SEE MOST ACTIVITY ENDING BY MID MORNING MONDAY. CURRENT RADAR IS BEGINNING TO SHOW ECHOES ACROSS CENTRAL NORTH DAKOTA WITH MINIMAL GROUND TRUTH...MAINLY MID LEVEL DECK. THE NAM HAS DRIED THAT OUT IN THE EVENING HOURS...SO WILL NEED TO MONITOR OVER NEXT COUPLE OF HOURS AND SEE HOW THINGS EVOLVE AS THESE INITIAL (WEAK) ECHOES DRIFT EAST...AND WILL SPEED THINGS UP AS NECESSARY WITH 18Z UPDATE UPDATE ISSUED AT 709 AM CDT SUN MAY 4 2014 BAND OF LIGHT RAIN SHOWERS REMAINING JUST SOUTH OF THE AREA AND MOVING INTO SW MN ATTM. OTHERWISE EXTENSIVE MID AND HIGH LEVEL MOISTURE MOVING INTO ERN ND SO UPPED SKY COVER SOME FOR TODAY. OTHERWISE NO CHANGES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 347 AM CDT SUN MAY 4 2014 BAND OF SHOWERS FROM DICKINSON ND AREA TO SOUTH OF BISMARCK TO ABERDEEN SD MOVING SOUTHEAST. LOOKS LIKE THIS BAND WILL STAY JUST SOUTH OF OUR FCST AREA. THIS ASSOCIATED WITH MID LEVEL FRONTOGENESIS. FARTHER SOUTH ACTUALLY A FEW HIGH BASED THUNDERSTORMS IN CENTRAL SD EAST OF PIERRE TOWARD HURON. THIS FORCING WILL EXIT SOUTHEAST THIS MORNING. OTHERWISE...SKIES CLEAR NE 1/2 OF FCST AREA ALONG AND NORTH OF CANDO-GRAND FORKS-PARK RAPIDS LINE. EXPECT GENERAL INCREASE IN HIGH CLOUDS TO SPREAD EAST THIS MORNING WITH THICKER CLOUD COVER SPREADING OVER MUCH OF THE AREA THIS AFTN/EVE AHEAD OF UPSTREAM SHORTWAVE IN MONTANA. THE UPSTREAM SHORT WAVE WILL MOVE INTO WRN ND TODAY AND THRU ERN ND/NW MN TONIGHT. WEAK FRONTOGENTICAL FORCING BUT SOME MID LEVEL WARM ADVECTION ASSOCIATED WITH THIS WAVE AND WITH SHOWERS ON RADARS TO OUR WEST WENT ALONG WITH WFO BIS AND INCREASED POPS IN NE ND INTO THE CNTRL RRV TONIGHT. MONDAY WILL SEE ANY PRECIP EXIT THE MN FCST AREA EARLY...BUT CONSIDERABLE MID AND HIGH LEVEL MOISTURE REMAINING. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 347 AM CDT SUN MAY 4 2014 WILL MAINTAIN A LOW POP IN FAR WRN FCST AREA MON NIGHT AS MOISTURE RETURNS NORTHEAST AHEAD OF NEXT LARGER SYSTEM. THEN INCREASING PRECIP CHANCES TO SPREAD INTO THE AREA DAYTIME TUESDAY AS 850-700 MB WARM/MOIST ADVECTION RETURNS AHEAD OF LARGE SCALE 500 MB TROUGH THAT WILL BE MOVING INTO THE ROCKIES. FOR WEDNESDAY THROUGH SUNDAY...CONSISTENCY THIS PERIOD CONTINUES WITH LATEST SUITE OF MODELS AS IT RELATES TO THE LARGE SCALE. QUESTIONS ABOUND REGARDING THE AMOUNT OF QPF THAT WILL DEVELOP OVER THE NORTHWEST HALF OF THE CWFA BEHIND INVERTED TROUGH WEDNESDAY. CONVECTION FORECAST SOUTH AND EAST OF OUR CWFA MAY BLOCK THE DEEPER MOISTURE REDUCING OVERALL QPF. ECMWF AND NAM12/DGEX SUGGEST SAID CONVECTION BRUSHING THE SOUTHEAST PART OF THE FA WEDNESDAY. GFS IS FARTHEST NORTH AND WEST WITH INSTABILITY AFT 00Z THU. GEM-NH...ECMWF AND DGEX FARTHER SOUTHEAST SUGGEST TSRA RISK FOR OUR AREA IS PRETTY LOW. BEST TIMING WOULD BE IN THE 12Z WED - 06Z THU AND SHOULD BE ISOLD AT BEST. FOR THURSDAY THE MODELS ARE IN FAIR AGREEMENT WITH SURFACE LOW OVER CENTRAL PLAINS AND TROUGH APPROX FSD-DLH LINE. ISENTROPIC UPGLIDE... 850-500 DIV Q...700 FRONTOGEN AND COUPLED JET SUPPLYING THE LIFT FOR -RASH/-RA OVER MUCH OF THE CWFA. QUESTION AGAIN IS HOW MUCH PLAINS CONVECTION INTERFERES WITH MOISTURE TRANSPORT AND RESULTANT QPF. ON FRIDAY LOW WRAPS UP INTO WESTERN GREAT LAKES/SOUTHERN ONTARIO TAKING MOISTURE AND LIFT WITH IT. COLDER AIR ALOFT MAY YIELD TO SOME -RASH LATE FRIDAY. THIS DEPARTING SYSTEM QUICKLY FOLLOWED BY WAVES ROTATING AROUND BASE OF UPPER LOW OVER MANITOBA/SASKATCHEWAN BORDER REGION. THUS UNSETTLED...SHOWERY WEATHER IS SUGGESTED INTO THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 108 PM CDT SUN MAY 4 2014 MAINLY VFR TODAY AND TONIGHT. HIGH AND MID LEVEL MOISTURE WILL CONTINUE TO INCREASE TODAY FROM WEST TO EAST. A BAND OF RAIN SHOWERS WILL OCCUR TONIGHT...ESPECIALLY NEAR THE HIGHWAY TWO CORRIDOR. A BRIEF PERIOD OF MVFR CIGS WILL BE POSSIBLE DURING THE RAINFALL...BUT THE PROBABILITY FOR THESE CIGS IS LOW AT THIS POINT. WINDS ARE EXPECTED TO BECOME EAST/SOUTHEAST...BELOW 12 KNOTS. && .HYDROLOGY... ISSUED AT 108 PM CDT SAT MAY 3 2014 TRIBUTARIES INTO THE MAINSTEM RED CONTINUE TO SEE FALLING STAGES. THE RED RIVER AT FARGO IS FORECAST TO FALL BELOW MODERATE FLOOD STAGE OVERNIGHT TONIGHT. FARTHER NORTH...A BROAD FLAT CREST HAS OCCURRED ACROSS CENTRAL INTO NORTHERN SECTIONS OF THE RED. A VERY GRADUAL RECESSION IN STAGES IS FORECAST FROM EAST GRAND FORKS TO OSLO...WITH SOME GRADUAL RISES ANTICIPATED TO CONTINUE FROM DRAYTON NORTHWARD TO PEMBINA BELOW FLOOD STAGE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...SPEICHER SHORT TERM...RIDDLE LONG TERM...EWENS/RIDDLE AVIATION...TG HYDROLOGY...MAKOWSKI
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1223 PM CDT SUN MAY 4 2014 .UPDATE... SEE THE UPDATED AVIATION DISCUSSION BELOW. ANOTHER QUICK UPDATE THIS MORNING TO COOL TEMPERATURES DOWN A FEW DEGREES MAINLY ALONG AND NORTH OF A LINE FROM TIMBER LAKE TO HAYTI...GIVEN EXPECTED DURATION OF CLOUDINESS AND ONGOING LOW LEVEL CAA ACROSS THE NORTHEASTERN HALF OF THE CWA ON EAST-SOUTHEASTERLY WINDS TODAY. DID NUDGE THE SOUTHWESTERN FORECAST ZONES UP A FEW DEGREES AS THAT AREA IS EXPECTED TO SEE SOME SUNSHINE BY EARLY THIS AFTERNOON. ALSO UPDATING THIS MORNING TO SCALE BACK POPS AND WIND DOWN THE POPS/WX MENTION SOONER...AND ELIMINATED THE LATE AFTERNOON POPS/WX MENTION ALTOGETHER...AS IT APPEARS THE NEXT AREA OF LOW PRESSURE MAY BE DELAYED A BIT AND PERHAPS MORE FOCUSED NORTH OF THIS CWA LATER TONIGHT. UPDATES ARE OUT. HYDROLOGY...WITH RECENT RAINFALL AND ONGOING UPSTREAM WATER RELEASES...THE JAMES RIVER IS JUST ABOUT TO HIT FLOOD STAGE...WHICH IS 13 FEET. THE LATEST RIVER FORECAST GUIDANCE CALLS FOR THE JAMES RIVER NEAR COLUMBIA TO RISE ABOVE FLOOD STAGE BY LATE THIS AFTERNOON...CRESTING AT APPX 13.5 FEET BY LATE MONDAY NIGHT. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH TUESDAY CURRENT RADAR IMAGERY SHOWING SCT SHOWERS AND EVEN A FEW THUNDERSHOWERS ACROSS CENTRAL SD AS MID LEVEL IMPULSE MOVES THROUGH. FURTHER EAST IN THE COLDER AIR...A MIX OF RAIN/SLEET/SNOW WAS OBSERVED AT ABR. HAVE ADJUSTED POP/WX GRIDS ACCORDINGLY AND WILL LIKELY NEED ADDITIONAL UPDATES IN A COUPLE HOURS. THE PAST SEVERAL RUNS OF THE HRRR AND THE 00Z EC HANDLED THIS SITUATION THE BEST...WITH THE 00Z GFS AND NAM WAY TOO FAR NORTH WITH THE PRECIPITATION. EXPECT THIS ACTIVITY TO CONTINUE SLIDING EAST THROUGH THE MORNING...MAINLY AFFECTING AREAS EAST OF THE MISSOURI RIVER. WITH COOL EASTERLY SFC FLOW DEVELOPING ALONG WITH PARTLY TO MOSTLY CLOUDY SKIES...WILL BE A COOL DAY TODAY WITH HIGHS ONLY IN THE LOW TO MID 50S FOR MOST AREAS. WILL SEE ANOTHER WAVE OF ENERGY TACK EAST ACROSS THE AREA OVERNIGHT...AND A SLIGHTLY STRONGER ONE MONDAY NIGHT INTO TUESDAY. ALTHOUGH THE LATTER SYSTEM LOOKS TO BRING BEST PRECIP CHANCES TO THE WESTERN CWA AT THIS TIME. AS FAR AS INSTABILITY GOES...IT APPEARS WESTERN AND CENTRAL SD STAND THE BEST CHANCE TO SEE ANY CONVECTION WITH THESE COMING WAVES OF ENERGY. .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY AN AREA OF LOW PRESSURE WILL MOVE INTO THE CENTRAL PLAINS AT THE START OF THE PERIOD. THIS SYSTEM COMBINED WITH UPPER LEVEL SOUTHWEST FLOW WILL BRING INSTABILITY AND TSTORM CHANCES TO THE NORTHERN PLAINS THROUGH WED NIGHT. AN UPPER LOW WILL THEN TRANSITION OVER SD/NE BRINGING CONTINUED STORM CHANCES THURSDAY. BY FRIDAY SFC HIGH PRESSURE WILL BRIEFLY BUILD IN TO THE PLAINS BRINGING DRIER WEATHER. THEN A TROUGH MOVES THROUGH ON SAT EVEN AS ANOTHER LONG WAVE TROF TO THE WEST BEGINS TO EJECT UPPER LEVEL ENERGY INTO THE DAKOTAS. THIS MEANS TSTORMS WILL BE BACK IN THE FORECAST FOR THE WEEKEND. TEMPERATURES WILL BE NEAR OR BELOW NORMAL THROUGH THE PERIOD DUE TO RAIN AND CLOUD COVER. GOOD MIXING ON MOST DAYS EXCEPT FRIDAY WILL PUSH HIGHS INTO THE 60S. && .AVIATION... 18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. STRATUS WILL REMAIN OVER THE REGION FOR MUCH OF THE DAY...HOWEVER CIGS ARE EXPECTED TO REMAIN AT OR ABOVE 5000 FT. ALSO...THE PRESSURE GRADIENT WILL INCREASE AS AN AREA OF LOW PRESSURE MOVES EAST. THE RESULT WILL BE INCREASING EAST SOUTHEAST WINDS...WITH GUSTS UP TO 20 KTS POSSIBLE ACROSS WESTERN SOUTH DAKOTA THIS AFTERNOON. THERE IS A SLIGHT CHANCE OF SHOWERS ACROSS CENTRAL SOUTH DAKOTA BY MONDAY MORNING...HOWEVER DID NOT MENTION IN THE TAFS AT THIS TIME. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...DORN SHORT TERM...TMT LONG TERM...WISE AVIATION...SERR WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
132 PM EDT SUN MAY 4 2014 .SYNOPSIS... A FRONT WILL BECOME STATIONARY FROM VIRGINIA TO THE MID MISSISSIPPI VALLEY BY LATE TODAY. THIS BOUNDARY WILL REMAIN IN THE AREA THROUGH WEDNESDAY...THEN LIFT NORTH INTO NEW ENGLAND. THURSDAY AND FRIDAY HIGH PRESSURE ALOFT AND UNSEASONABLY WARM AIR BUILD OVER THE MID ATLANTIC REGION. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1228 PM EDT SUNDAY... MODIFIED TEMPERATURES AND HIGH TEMPERATURES UP A FEW DEGREES IN THE EAST. RUC13 AND NAM12 SHOWED INCREASE IN WINDS 18-21Z THIS AFTERNOON. WITH 10 HOUR FUELS DRYING THIS AFTERNOON...EXPANDED ENHANCE FIRE STATEMENT NORTHWARD ALONG THE BLUE RIDGE. AS OF 952 AM EDT SUNDAY... ADJUSTED TEMPERATURES AND DEW POINTS ACCORDING TO LATEST OBS AND MODEL TRENDS. SHORTWAVE TROUGH WILL PIVOT ACROSS THE REGION AROUND 00Z AND PUSHES OFFSHORE OVERNIGHT. THE SWODY1 BRINGS A CHANCE OF THUNDERSTORMS INTO WESTERN PORTIONS OF CWA. THE NAM...GFS AND ECMWF SUPPORT THE MENTION OF ISOLATED THUNDERSTORMS IN THE WEST. THE LOCAL RNK WRF ARW KEPT THE THUNDERSTORM AND SHOWER THREAT NORTH OF CWA THROUGH THIS AFTERNOON. WINDS WILL BE GUSTING OUT OF THE NORTHWEST THIS AFTERNOON...THIS WILL HINDER COVERAGE OF ANY SHOWERS OR THUNDERSTORMS EAST OF THE BLUE RIDGE. HELD ON TO CURRENT FORECAST HIGHS FROM THE UPPER 60S IN THE NORTHWEST MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT. AS OF 400 AM EDT SUNDAY... CLOSED UPPER LOW OVER THE GREAT LAKES MOVES ACROSS NEW ENGLAND BY THIS AFTERNOON. THIS KEEPS THE FORECAST AREA IN DEEP NORTHWEST FLOW THROUGH TONIGHT. WEAK STATIONARY FRONT WITH AXIS OF DEEPER MOISTURE SETS UP FROM SOUTHERN INDIANA TO CENTRAL VIRGINIA TODAY. MODELS STILL DIFFER IN EXACT ALIGNMENT OF WHERE PRECIPITATION MAY ENTER THE COUNTY WARNING AREA LATE THIS AFTERNOON. BETTER INSTABILITY REMAINS JUST WEST OF THE FORECAST AREA THROUGH MID AFTERNOON. THUNDERSTORMS THAT DEVELOP TO THE WEST WILL TRACK INTO THE AREA LATE TODAY. RAP GUIDANCE HAS PRECIPITATION AFTER 2PM AS FAR NORTHERN AS GREENBRIER COUNTY...WHILE THE NAM AND GFS WERE POINTING MORE TOWARD TAZEWELL AND SMYTH COUNTIES. PLENTY OF SUNSHINE THIS MORNING TO PRODUCE DEEP MIXING. WINDS WILL BE GUSTING OUT OF THE NORTHWEST SO COVERAGE OF ANY SHOWERS OR THUNDERSTORMS THAT GET ACROSS THE BLUE RIDGE WILL BE LIMITED. BUFKIT SUPPORTED WIND GUSTS OF 30 TO 40 MPH ABOVE 3000 FEET THIS AFTERNOON AND EARLY EVENING WITH WIND SPEEDS DROPPING OFF QUICKLY WITH THE LOSS OF HEATING. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM EDT SUNDAY... AN UPPER TROUGH BUILDING ALONG THE WEST COAST WILL EVENTUALLY CARVE A CLOSED UPPER LOW OVER SOUTHERN CALIFORNIA BY TUESDAY. IN RESPONSE...HEIGHTS WILL BUILD THROUGH THE MISSISSIPPI RIVER VALLEY AND GREAT LAKES. CONFLUENCE OVER NEW ENGLAND WILL PRODUCE A SURFACE HIGH WHICH WILL WEDGE INTO VIRGINIA...PERHAPS SENDING SLIGHTLY COOLER AND DRIER AIR INTO SW VA. THE STRENGTH AND POSITION OF THIS DIFFUSE BOUNDARY WILL DETERMINE CHANCES FOR PRECIP TUESDAY AND WEDNESDAY. MONDAY HOLDS THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS...MAINLY RT 460 AND POINTS NORTH. ALTHOUGH SOME SREF MEMBERS ARE SENDING PRECIP SOUTH OF THIS LINE...THE OP GFS SEEMS TO CONTAIN CONVECTIVE FEEDBACK WITH A SPURIOUS VORT MAX OVER WESTERN NORTH CAROLINA AT 0Z TUES. HOWEVER...CAN`T TOTALLY RULE OUT SHOWERS AND A FEW STORMS NEAR THE NC/VA BORDER MONDAY. INSTABILITY DEFINITELY EXISTS ON MONDAY...AND OF COURSE WITH THE POSITION OF THE STATIONARY BOUNDARY...GOOD LLVL SHEAR IS ALSO A FACTOR. THE MISSING INGREDIENT IN THE STEW IS FORCING...AS THERE DOESN`T SEEM TO BE MUCH OF A TRIGGER FOR SURFACE PARCELS. PERHAPS A CLEARER SKY AND MORE SUNSHINE MONDAY MORNING WILL PROVIDE THAT EXTRA NUDGE NECESSARY. COULD BE AN ISOLATED STRONG STORM RT 460 AND NORTH MONDAY. SOME EASTERLY COMPONENT AND THE POSITION OF THE BOUNDARY OVER SW VA COULD KEEP LYH/ROA COOLER THAN BLF/JFZ/MKJ CORRIDOR BOTH TUESDAY AND WEDNESDAY. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 345 PM EDT SATURDAY... PROGRESSIVE PATTERN WILL BECOME MORE AMPLIFIED DURING THE PERIOD AS DEEP UPPER TROUGH DEVELOPS IN THE WESTERN U.S. AND TROUGHING DEEPENS OVER THE NORTHERN ATLANTIC. THIS WILL RESULT IN AN AMPLIFYING MID-LEVEL RIDGE THROUGH THE OH/TN VALLEY. THE LONG STANDING BAROCLINIC ZONE OF THE FIRST HALF OF THE WEEK WILL BEGIN TO LIFT NORTH OF THE REGION WEDNESDAY...BUT MODELS NOW INDICATING THAT IT WILL BE AT LEAST ONE DAY SLOWER TO EXIST TO THE NORTHEAST THAN EARLIER INDICATED. THUS...THERE REMAINS THE POTENTIAL FOR SHRA/TSRA TO AGAIN DEVELOP WED AFTERNOON. BY THIS TIME...THE BEST SUPPORT WILL BE ACROSS THE ALLEGHANY HIGHLANDS AND SHENANDOAH VALLEY NORTHWARD...OR MAINLY NORTH OF I-64. HAVE TAILORED POPS ACCORDINGLY. THU STILL LIKES A DRY AND WARM DAY AS THE UPPER RIDGE DRIFTS OVER THE REGION. FOR FRI-SAT...THE MODELS HAVE COME INTO BETTER AGREEMENT ON THE MOVEMENT OF THE CENTRAL U.S. TROUGH INTO THE EASTERN U.S. THE MAJORITY OF THE PCPN WILL REMAIN WEST OF THE CWA THROUGH FRI...BUT BY SAT LIKELY POPS APPEAR IN ORDER FOR THE WV COUNTIES DOWN THROUGH SW VA/NW NC. THIS SYSTEM STILL OFFERS THE NEXT BEST CHANCE FOR WIDESPREAD RAINFALL FOR THE CWA. TOO FAR OUT TO GET INTO ANY SPECIFIC DETAILS...BUT HIGH CHC TO LOW LIKELY POPS IN ORDER FOR WESTERN AREAS AS INDICATED AND IN AGREEMENT WITH OUR WESTERN NEIGHBORS FOR NEXT SAT. MODELS SHOW A DISTINCT COOLING TREND FOR WED THAT APPEARS CONTRARY TO THE AMPLIFYING RIDGE. HOWEVER...A WEAK WEDGE PATTERN APPEARS EVIDENT UNDER THE AMPLIFYING RIDGE...WHICH COULD TEMPER THE WARMING ALOFT. AGAIN...HAVE GONE WITH A GENERAL MODEL BLEND. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 130 PM EDT SUNDAY... A WEAK FRONT WILL EXTEND ACROSS KENTUCKY INTO WESTERN VIRGINIA THIS AFTERNOON AND TONIGHT. THIS BOUNDARY WILL PROVIDE SOME LOW LEVEL CONVERGENCE...ENOUGH TO DEVELOP A FEW SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. HAVE KEPT VICINITY SHOWERS IN THE BCB/BLF/LWB AND ROA TAFS AFTER 20Z/4PM TODAY BUT REMOVED THUNDERSTORMS SINCE THE PROBABILITY OF A STORM AT THESE AIRPORTS IS VERY LOW. HIGH TO MEDIUM CONFIDENCE IN CEILINGS AND VISIBILITIES DURING THE TAF PERIOD. HIGH CONFIDENCE THAT WINDS GUSTS FROM 25 TO 30 KNOTS WILL BE COMMON THIS AFTERNOON. WINDS WILL DIMINISH THIS EVENING AROUND SUNSET. TONIGHT INTO WEDNESDAY...THE FRONT WILL STALL OVER THE FORECAST AREA. IMPULSES ALONG THIS BOUNDARY WILL BRING AN INCREASING CHANCE FOR SUB-VFR CEILINGS AND PERIODS OF SHRA/TSRA. THURSDAY THE FRONT LIFTS NORTH WITH DRIER WEATHER AND WARMER AIR MOVING INTO THE REGION. && .FIRE WEATHER... AS OF 1228 PM EDT SUNDAY... IN COORDINATION WITH FORESTRY OFFICIALS AND SURROUNDING NATIONAL WEATHER SERVICE OFFICES...HAVE EXPANDED THE SPECIAL WEATHER STATEMENT FOR ENHANCED FIRE DANGER NORTHWARD ALONG AND EAST OF THE BLUE RIDGE FOR THIS AFTERNOON INTO THIS EVENING. MOST CRITICAL CONDITIONS WILL BE FROM NOON THROUGH 8PM WHEN HUMIDITIES WILL BE AS LOW AS 25 PERCENT AND WIND WILL BE GUSTING FROM THE NORTHWEST AT 20 TO 30 MPH. WESTERN COUNTIES RECEIVE MORE RAINFALL FROM THE STORM SYSTEM LAST WEEK AND FUEL LEVELS ARE HIGHER. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/KK SHORT TERM...KM LONG TERM...RAB AVIATION...AMS/KK FIRE WEATHER...AMS/KK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1228 PM EDT SUN MAY 4 2014 .SYNOPSIS... A FRONT WILL BECOME STATIONARY FROM VIRGINIA TO THE MID MISSISSIPPI VALLEY BY LATE TODAY. THIS BOUNDARY WILL REMAIN IN THE AREA THROUGH WEDNESDAY...THEN LIFT NORTH INTO NEW ENGLAND. THURSDAY AND FRIDAY HIGH PRESSURE ALOFT AND UNSEASONABLY WARM AIR BUILD OVER THE MID ATLANTIC REGION. && .NEAR TERM /THROUGH TONIGHT/... MODIFIED TEMPERATURES AND HIGH TEMPERATURES UP A FEW DEGREES IN THE EAST. RUC13 AND NAM12 SHOWED INCREASE IN WINDS 18-21Z THIS AFTERNOON. WITH 10 HOUR FUELS DRYING THIS AFTERNOON...EXPANDED ENHANCE FIRE STATEMENT NORTHWARD ALONG THE BLUE RIDGE. AS OF 952 AM EDT... ADJUSTED TEMPERATURES AND DEW POINTS ACCORDING TO LATEST OBS AND MODEL TRENDS. SHORTWAVE TROUGH WILL PIVOT ACROSS THE REGION AROUND 00Z AND PUSHES OFFSHORE OVERNIGHT. THE SWODY1 BRINGS A CHANCE OF THUNDERSTORMS INTO WESTERN PORTIONS OF CWA. THE NAM...GFS AND ECMWF SUPPORT THE MENTION OF ISOLATED THUNDERSTORMS IN THE WEST. THE LOCAL RNK WRF ARW KEPT THE THUNDERSTORM AND SHOWER THREAT NORTH OF CWA THROUGH THIS AFTERNOON. WINDS WILL BE GUSTING OUT OF THE NORTHWEST THIS AFTERNOON...THIS WILL HINDER COVERAGE OF ANY SHOWERS OR THUNDERSTORMS EAST OF THE BLUE RIDGE. HELD ON TO CURRENT FORECAST HIGHS FROM THE UPPER 60S IN THE NORTHWEST MOUNTAINS TO THE LOWER 80S IN THE PIEDMONT. AS OF 400 AM EDT SUNDAY... CLOSED UPPER LOW OVER THE GREAT LAKES MOVES ACROSS NEW ENGLAND BY THIS AFTERNOON. THIS KEEPS THE FORECAST AREA IN DEEP NORTHWEST FLOW THROUGH TONIGHT. WEAK STATIONARY FRONT WITH AXIS OF DEEPER MOISTURE SETS UP FROM SOUTHERN INDIANA TO CENTRAL VIRGINIA TODAY. MODELS STILL DIFFER IN EXACT ALIGNMENT OF WHERE PRECIPITATION MAY ENTER THE COUNTY WARNING AREA LATE THIS AFTERNOON. BETTER INSTABILITY REMAINS JUST WEST OF THE FORECAST AREA THROUGH MID AFTERNOON. THUNDERSTORMS THAT DEVELOP TO THE WEST WILL TRACK INTO THE AREA LATE TODAY. RAP GUIDANCE HAS PRECIPITATION AFTER 2PM AS FAR NORTHERN AS GREENBRIER COUNTY...WHILE THE NAM AND GFS WERE POINTING MORE TOWARD TAZEWELL AND SMYTH COUNTIES. PLENTY OF SUNSHINE THIS MORNING TO PRODUCE DEEP MIXING. WINDS WILL BE GUSTING OUT OF THE NORTHWEST SO COVERAGE OF ANY SHOWERS OR THUNDERSTORMS THAT GET ACROSS THE BLUE RIDGE WILL BE LIMITED. BUFKIT SUPPORTED WIND GUSTS OF 30 TO 40 MPH ABOVE 3000 FEET THIS AFTERNOON AND EARLY EVENING WITH WIND SPEEDS DROPPING OFF QUICKLY WITH THE LOSS OF HEATING. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 330 AM EDT SUNDAY... AN UPPER TROUGH BUILDING ALONG THE WEST COAST WILL EVENTUALLY CARVE A CLOSED UPPER LOW OVER SOUTHERN CALIFORNIA BY TUESDAY. IN RESPONSE...HEIGHTS WILL BUILD THROUGH THE MISSISSIPPI RIVER VALLEY AND GREAT LAKES. CONFLUENCE OVER NEW ENGLAND WILL PRODUCE A SURFACE HIGH WHICH WILL WEDGE INTO VIRGINIA...PERHAPS SENDING SLIGHTLY COOLER AND DRIER AIR INTO SW VA. THE STRENGTH AND POSITION OF THIS DIFFUSE BOUNDARY WILL DETERMINE CHANCES FOR PRECIP TUESDAY AND WEDNESDAY. MONDAY HOLDS THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS...MAINLY RT 460 AND POINTS NORTH. ALTHOUGH SOME SREF MEMBERS ARE SENDING PRECIP SOUTH OF THIS LINE...THE OP GFS SEEMS TO CONTAIN CONVECTIVE FEEDBACK WITH A SPURIOUS VORT MAX OVER WESTERN NORTH CAROLINA AT 0Z TUES. HOWEVER...CAN`T TOTALLY RULE OUT SHOWERS AND A FEW STORMS NEAR THE NC/VA BORDER MONDAY. INSTABILITY DEFINITELY EXISTS ON MONDAY...AND OF COURSE WITH THE POSITION OF THE STATIONARY BOUNDARY...GOOD LLVL SHEAR IS ALSO A FACTOR. THE MISSING INGREDIENT IN THE STEW IS FORCING...AS THERE DOESN`T SEEM TO BE MUCH OF A TRIGGER FOR SURFACE PARCELS. PERHAPS A CLEARER SKY AND MORE SUNSHINE MONDAY MORNING WILL PROVIDE THAT EXTRA NUDGE NECESSARY. COULD BE AN ISOLATED STRONG STORM RT 460 AND NORTH MONDAY. SOME EASTERLY COMPONENT AND THE POSITION OF THE BOUNDARY OVER SW VA COULD KEEP LYH/ROA COOLER THAN BLF/JFZ/MKJ CORRIDOR BOTH TUESDAY AND WEDNESDAY. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 345 PM EDT SATURDAY... PROGRESSIVE PATTERN WILL BECOME MORE AMPLIFIED DURING THE PERIOD AS DEEP UPPER TROUGH DEVELOPS IN THE WESTERN U.S. AND TROUGHING DEEPENS OVER THE NORTHERN ATLANTIC. THIS WILL RESULT IN AN AMPLIFYING MID-LEVEL RIDGE THROUGH THE OH/TN VALLEY. THE LONG STANDING BAROCLINIC ZONE OF THE FIRST HALF OF THE WEEK WILL BEGIN TO LIFT NORTH OF THE REGION WEDNESDAY...BUT MODELS NOW INDICATING THAT IT WILL BE AT LEAST ONE DAY SLOWER TO EXIST TO THE NORTHEAST THAN EARLIER INDICATED. THUS...THERE REMAINS THE POTENTIAL FOR SHRA/TSRA TO AGAIN DEVELOP WED AFTERNOON. BY THIS TIME...THE BEST SUPPORT WILL BE ACROSS THE ALLEGHANY HIGHLANDS AND SHENANDOAH VALLEY NORTHWARD...OR MAINLY NORTH OF I-64. HAVE TAILORED POPS ACCORDINGLY. THU STILL LIKES A DRY AND WARM DAY AS THE UPPER RIDGE DRIFTS OVER THE REGION. FOR FRI-SAT...THE MODELS HAVE COME INTO BETTER AGREEMENT ON THE MOVEMENT OF THE CENTRAL U.S. TROUGH INTO THE EASTERN U.S. THE MAJORITY OF THE PCPN WILL REMAIN WEST OF THE CWA THROUGH FRI...BUT BY SAT LIKELY POPS APPEAR IN ORDER FOR THE WV COUNTIES DOWN THROUGH SW VA/NW NC. THIS SYSTEM STILL OFFERS THE NEXT BEST CHANCE FOR WIDESPREAD RAINFALL FOR THE CWA. TOO FAR OUT TO GET INTO ANY SPECIFIC DETAILS...BUT HIGH CHC TO LOW LIKELY POPS IN ORDER FOR WESTERN AREAS AS INDICATED AND IN AGREEMENT WITH OUR WESTERN NEIGHBORS FOR NEXT SAT. MODELS SHOW A DISTINCT COOLING TREND FOR WED THAT APPEARS CONTRARY TO THE AMPLIFYING RIDGE. HOWEVER...A WEAK WEDGE PATTERN APPEARS EVIDENT UNDER THE AMPLIFYING RIDGE...WHICH COULD TEMPER THE WARMING ALOFT. AGAIN...HAVE GONE WITH A GENERAL MODEL BLEND. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 730 AM EDT SUNDAY... ONLY SCATTERED CLOUDS ARE EXPECTED THROUGH MID MORNING WITH NO REDUCTION IN VISIBILITY. A WEAK FRONT WILL EXTEND ACROSS KENTUCKY INTO WESTERN VIRGINIA THIS AFTERNOON AND TONIGHT. THIS BOUNDARY WILL PROVIDE SOME LOW LEVEL CONVERGENCE...ENOUGH TO DEVELOP SHOWERS AND ISOLATED THUNDERSTORMS THIS AFTERNOON. HAVE KEPT SHOWERS IN THE BCB/BLF/LWB AND ROA TAFS AFTER 20Z/4PM TODAY BUT REMOVED THUNDERSTORMS SINCE THE PROBABILITY OF A STORM AT THESE AIRPORTS IS VERY LOW. WINDS WILL BEGIN GUSTING ONCE MORNING INVERSION MIXES OUT...AROUND 15Z/11AM. HIGH CONFIDENCE THAT WINDS GUSTS FROM 25 TO 30 KNOTS WILL BE COMMON THIS AFTERNOON. WINDS WILL DIMINISH THIS EVENING AROUND SUNSET. TONIGHT INTO WEDNESDAY...THE FRONT WILL STALL OVER THE FORECAST AREA. IMPULSES ALONG THIS BOUNDARY WILL BRING AN INCREASING CHANCE FOR SUB-VFR CEILINGS AND PERIODS OF SHRA/TSRA. THURSDAY THE FRONT LIFTS NORTH WITH DRIER WEATHER AND WARMER AIR MOVING INTO THE REGION. && .FIRE WEATHER... IN COORDINATION WITH FORESTRY OFFICIALS AND SURROUNDING NATIONAL WEATHER SERVICE OFFICES...HAVE EXPANDED THE SPECIAL WEATHER STATEMENT FOR ENHANCED FIRE DANGER NORTHWARD ALONG AND EAST OF THE BLUE RIDGE FOR THIS AFTERNOON INTO THIS EVENING. MOST CRITICAL CONDITIONS WILL BE FROM NOON THROUGH 8PM WHEN HUMIDITIES WILL BE AS LOW AS 25 PERCENT AND WIND WILL BE GUSTING FROM THE NORTHWEST AT 20 TO 30 MPH. WESTERN COUNTIES RECIEVE MORE RAINFALL FROM THE STORM SYSTEM LAST WEEK AND FUEL LEVELS ARE HIGHER. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...AMS/KK SHORT TERM...KM LONG TERM...RAB AVIATION...AMS FIRE WEATHER...AMS/KK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1231 PM CDT SUN MAY 4 2014 .UPDATE... ISSUED AT 702 AM CDT SUN MAY 4 2014 A BAND OF STRONG 900 TO 500 MB FRONTOGENESIS WILL BRUSH NORTHEAST IOWA AND A SMALL PART OF SOUTHEAST MINNESOTA THIS MORNING. THIS BAND IS CURRENTLY PRODUCING A BAND OF RAIN ACROSS SOUTHWEST MINNESOTA AND NORTH CENTRAL IOWA. THE HRRR SEEMS TO HAVE THE BEST HANDLE ON THIS AND SHOWS THE BAND MOVING THROUGH OUR 5 WESTERN COUNTIES IN NORTHEAST IOWA. DUE TO THIS...RAISED THE RAIN CHANCES UP TO 50 PERCENT FROM 04.13Z TO 04.16Z. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 230 AM CDT SUN MAY 4 2014 CURRENTLY AS OF 07Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED A DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST...RIDGING DOWNSTREAM OVER THE ROCKIES AND WESTERN PLAINS...AND MORE TROUGHING OVER THE GREAT LAKES. ON THE SOUTHWEST SIDE OF THIS GREAT LAKES TROUGH...A 100 KT JET STREAK NEAR 250MB EXTENDED FROM INTERNATIONAL FALLS MN TO TRAVERSE CITY MI PER RAP ANALYSIS. THIS JET STREAK WAS AIDING IN A MID LEVEL FRONTOGENESIS ZONE TO ITS SOUTHWEST OVER THE EASTERN DAKOTAS INTO SOUTHERN MN. EXTENSIVE MID CLOUDS FROM SOUTH DAKOTA EASTWARD TO LOCATIONS SOUTHWEST OF I-94 IN THE FORECAST AREA EXIST AS A RESULT OF THIS FRONTOGENESIS ZONE. RADAR IMAGERY DEPICTS TWO BANDS OF SHOWER ACTIVITY ACROSS SOUTH DAKOTA BUT NO PRECIPITATION HAS BEEN REPORTED DUE TO DRY LOW LEVEL AIR. BANDS ACROSS SOUTHERN SOUTH DAKOTA ACTUALLY PRODUCING SOME LIGHTNING FROM STEEPER MID LEVEL LAPSE RATES COMING OFF THE ROCKIES. 925MB DEWPOINT DEPRESSIONS WERE 10-15C AT 00Z AT BIS...ABR AND MPX...HELPING TO PREVENT RAIN FROM REACHING THE GROUND. ALONG WITH THE DRY AIR...COOLER AIR WAS ADVECTING SOUTHEASTWARD FROM CANADA INTO THE FORECAST AREA. 925MB TEMPS AT BIS AND ABR FELL 5-6C OVER THE PAST 24 HOURS. UPPER RIDGING OVER THE ROCKIES IS PROGGED TO SLIDE FULLY OVER THE PLAINS BY 12Z MONDAY...PUSHED AHEAD BY THE DEEP TROUGH COMING INTO THE PACIFIC NORTHWEST. WITH THE FORECAST AREA STAYING ON THE EAST SIDE OF THE RIDGE AXIS...THIS FAVORS SUBSIDENCE AND DRYING WITH HIGH PRESSURE AT THE SURFACE. HOWEVER...THERE ARE TWO CAVEATS TO THIS GENERALITY. 1. THIS MORNING WITH THE MID-LEVEL FRONTOGENESIS ZONE AND RIGHT ENTRANCE REGION OF THE JET STREAK. MODELS HAVE DEFINITELY TRENDED WEAKER WITH THIS FRONTOGENESIS...EVEN JUST BETWEEN THE 03.18Z AND 04.00Z NAM. AS A RESULT...THE 04.00Z GFS/NAM/REGIONAL CANADIAN HAVE REALLY BACKED OFF ON THE IDEA OF RAIN ACROSS SOUTHERN MN...NORTHERN IA...SOUTHERN WI AND NORTHERN IL THIS MORNING. 04.06Z RAP AND 04.04Z HRRR...WHICH ARE MIMICKING NICELY WHAT HAS BEEN GOING ON IN THE DAKOTAS...ALSO ARE DRIER. THEREFORE...HAVE FOLLOWED SUIT AND REALLY LOWERED PRECIPITATION CHANCES. 2. 04.00Z NAM/REGIONAL CANADIAN/GFS/ECMWF DEPICT ANOTHER BAND OF MID LEVEL FRONTOGENESIS TO TRACK OUT OF NORTH DAKOTA THIS AFTERNOON AND ACROSS LOCATIONS MAINLY NORTH OF I-94 BETWEEN 06-12Z MONDAY. THERE WERE INDICATIONS IN PAST RUNS OF POSSIBLE PRECIPITATION FROM THIS BAND...BUT THE 04.00Z ARE THE MOST IMPRESSIVE THUS FAR. THEREFORE...HAVE ADDED 20 PERCENT CHANCES. STILL HAVE SOME CONCERNS FOR PRECIPITATION GIVEN HIGH PRESSURE PROGGED OVER UPPER MI...WHICH WOULD PROVIDE A FEED OF DRY LOW LEVEL AIR TO COUNTERACT RAIN FALLING TO THE SURFACE. COOLER TEMPERATURES ARE EXPECTED TODAY GIVEN 18Z 925MB TEMPS PROGGED AROUND 4C COMPARED TO 7-10C AT 18Z YESTERDAY. HIGHS SHOULD BE AT LEAST 5 IF NOT 10 DEGREES COOLER...COOLEST OVER NORTHEAST IOWA WITH MOST CLOUD COVER. BATCH OF MID CLOUDS COMING THROUGH WITH THE FRONTOGENESIS ZONE TONIGHT COMBINED WITH AN INCREASING SOUTHEAST 925MB WIND SHOULD HELP TEMPERATURES FROM BOTTOMING OUT TOO MUCH. GUIDANCE LOWS IN THE 30S SEEM REASONABLE. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 230 AM CDT SUN MAY 4 2014 BAND OF MID LEVEL FRONTOGENESIS ALONG/NORTH OF I-94 LATE TONIGHT LOOKS TO QUICKLY MOVE OFF TO THE EAST MONDAY MORNING. ONLY THE 04.00Z NAM LINGERS SOME LIGHT RAIN OVER TAYLOR/CLARK COUNTIES AFTER 12Z MONDAY. THEREFORE...HAVE FOLLOWED THE PREVIOUS FORECAST AND KEPT MONDAY DRY FOR NOW. DRY WEATHER IN FACT SHOULD PREVAIL ACROSS MUCH OF THE FORECAST AREA THROUGH TUESDAY AS THE AREA REMAINS UNDER THE INFLUENCE OF HIGH PRESSURE OVER THE WESTERN GREAT LAKES. THE MODERATING TREND IN TEMPERATURES FOR MONDAY THROUGH TUESDAY REMAINS CONSISTENT WITH 925MB READINGS CLIMBING TO 6-8C AT 18Z MONDAY AND 8- 10C AT 18Z TUESDAY. WITH SOME SUN...ESPECIALLY ON TUESDAY...SHOULD SEE HIGHS CLIMB INTO THE MID 50S/LOW 60S ON MONDAY AND LOW TO MID 60S ON TUESDAY. MONDAY NIGHT COULD BE RELATIVELY CHILLY ACROSS CENTRAL WISCONSIN WITH CALM WINDS AND DRY AIR IN PLACE. LOWS THERE MAY DIP CLOSE TO FREEZING. MODELS CONTINUE TO FORECAST AN ACTIVE WEATHER PATTERN FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT...IN RESPONSE TO A BIG PORTION OF A LONG WAVE UPPER TROUGH OVER THE WESTERN U.S. AT 00Z WEDNESDAY LIFTING NORTHEAST INTO THE REGION. THE BIGGEST CHANGE OVER THE LAST 24 HOURS WITH THIS PERIOD OF THE FORECAST IS THAT THE ASSOCIATED LOW PRESSURE SYSTEM LIFTING OUT OF THE CENTRAL PLAINS IS MUCH SLOWER TO CROSS THE AREA THURSDAY INTO THURSDAY NIGHT. A LOT OF THIS SLOWING APPEARS TO BE RELATED TO THE PORTION OF THE LONG WAVE TROUGH TAKING A MORE NORTHWESTWARD TRACK. HIGHLIGHTS... 1. ELEVATED CONVECTION TUESDAY NIGHT / WEDNESDAY MORNING. THIS SIGNAL HAS BEEN VERY CONSISTENT FOR THE PAST COUPLE OF DAYS. INCREASING 850MB MOISTURE TRANSPORT AND CAPE ARE PROGGED TO OCCUR OVER IOWA THROUGH THE NIGHT...NOSING INTO THE FORECAST AREA. SEEMS LIKELY TO AT LEAST GET ELEVATED CONVECTION AND POSSIBLY EVEN AN MCS. SHOULD AN MCS FORM...CORFIDI VECTORS WOULD SUPPORT THE IDEA OF THE 04.00Z NAM OF AN MCS TRACKING EAST-SOUTHEASTWARD ACROSS IOWA. IN ANY EVENT...GIVEN THE CONSISTENT SIGNAL...FELT INCREASE IN PRECIPITATION CHANCES SEEMS WARRANTED. WILL HAVE TO WATCH FOR POTENTIAL SEVERE WEATHER WITH LARGE HAIL THE MOST LIKELY CONCERN. 2. DURING THE DAY WEDNESDAY...04.00Z GFS/ECMWF DEPICT A LOT OF LIGHT PRECIP...MAINLY ALONG AND NORTH OF I-90 WHICH IS ALSO NORTH OF A WARM FRONT. SOUNDINGS SUGGEST THIS IS LOW LEVEL ISENTROPIC LIFT INDUCED BELOW A STRONG CAP...SO PERHAPS AFTER SOME MORNING STORMS WE END UP WITH A BUNCH OF DRIZZLE. THIS IDEA SEEMS REASONABLE WHICH ALSO MEANS A DECENT TEMPERATURE GRADIENT COULD SET UP OVER THE FORECAST AREA. 3. ANOTHER ROUND OF ELEVATED CONVECTION WEDNESDAY NIGHT IF THE 04.00Z GFS IS CORRECT...THOUGH THE 04.00Z ECMWF/CANADIAN SUGGEST THIS CONVECTION WOULD TAKE PLACE WELL NORTH OF THE FORECAST AREA WITH THE AREA UNDER THE 850MB MOISTURE TRANSPORT STREAM. FOR NOW MAINTAINED 20-50 PERCENT CHANCES. WEDNESDAY NIGHT IS LOOKING WARM AND HUMID AS WELL...ESPECIALLY COMPARED TO WHAT WE HAVE SEEN. 4. THURSDAY IS LOOKING MORE MESSY...ESPECIALLY FORECASTING THE HIGH TEMP. MODELS AGREE THE FORECAST AREA IS IN THE WARM SECTOR...WHICH NORMALLY SUGGESTS A CAPPED ATMOSPHERE. HOWEVER...THE 04.00Z ECMWF/CANADIAN/GFS ARE ALL POINTING TO A WARM CONVEYOR BELT OF SHOWERS AND STORMS ACROSS MUCH OF THE FORECAST AREA AHEAD OF THE SHORTWAVE TROUGH LIFTING THROUGH THE PLAINS. 04.00Z ECMWF HAS CUT HIGHS 5-8 DEGREES AS A RESULT. THUS...FOR NOW HAVE LEFT A CONSENSUS HIGH IN THE 70S. STILL...THIS IS MUCH WARMER THAN WHERE WE HAVE BEEN. 5. POSSIBLE SEVERE WEATHER LATE THURSDAY/THURSDAY NIGHT. GIVEN THE NORTHWESTWARD TREND OF THE PLAINS TROUGH...SLOWER COLD FRONTAL TIMING AND THAT WARM CONVEYOR BELT ON THURSDAY LIMITING DAYTIME INSTABILITY...VERY UNCLEAR ON HOW THURSDAY NIGHT WILL PLAY OUT. WOULDNT DOUBT THE FORECAST AREA IS IMPACTED BY STORMS...AND THUS HAVE 50-60 PERCENT CHANCES GOING. HOWEVER...THE TIMING MAY KEEP THE SEVERE CONCERN WEST OF THE AREA. MANY DAYS TO WORK OUT THE DETAILS. MAINTAINED SOME CHANCES FOR FRIDAY WITH POTENTIAL LINGERING SHOWERS ON THE WRAP AROUND OF THE SYSTEM. MUCH COOLER TEMPS FOR FRIDAY TOO. DRIER WEATHER FOLLOWS FOR FRIDAY NIGHT WITH HIGH PRESSURE SLIDING THROUGH...THEN A COLD FRONT LOOKS TO APPROACH FOR SATURDAY TO BRING THE NEXT CHANCE OF RAIN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1230 PM CDT SUN MAY 4 2014 FRONTOGENETIC BAND OF PRECIPITATION JUST TO THE SOUTH OF THE TAF LOCATIONS AT MID-DAY CONTINUES TO MAINTAIN MID CLOUD IN THE AREA. THIS GENERAL AREA OF FORCING...ALTHOUGH WEAKENING...WILL CONTINUE TO MAINTAIN THIS CLOUD COVER INTO TONIGHT. MEANWHILE...THE NEXT ROUND OF FRONTOGENETIC FORCING WILL MOVE INTO NORTHERN MN/WI TONIGHT...WITH ANOTHER BAND DEVELOPING ACROSS NORTHERN IL. TAF LOCATIONS LOOK TO BE BETWEEN THESE BANDS...SO DO NOT ANTICIPATE ANY PRECIPITATION...BUT MORE MID CLOUD AND PERHAPS SOME HIGH STRATO-CU WILL CONTINUE TO IMPACT THE TAF LOCATIONS. OTHER AVIATION CONCERN WILL BE WINDS AS HIGH PRESSURE MOVES OVERHEAD. LOW LEVEL WIND SWITCHING FROM NORTHEAST TO EAST AND THEN SOUTHEAST WITH TIME...WHILE UPPER LEVEL FLOW REMAINS WEST TO NORTHWEST. WHILE SPEEDS ARE NOT TERRIBLY HIGH...DIRECTION CHANGE WITH HEIGHT MAY BE OF INTEREST TO SOME AIRCRAFT. && .HYDROLOGY... ISSUED AT 230 AM CDT SUN MAY 4 2014 FLOODING CONTINUES ALONG THE MAINSTEM MISSISSIPPI RIVER AS RUNOFF FROM MELTING SNOW AND ALL OF THE RAINFALL OVER THE PAST 7-10 DAYS MOVES THROUGH THE WATERSHED. MOST OF THE TRIBUTARIES ARE FALLING AND SHOULD CONTINUE TO DO SO THE NEXT FEW DAYS. FOR THE MISSISSIPPI... CRESTS ARE EXPECTED FROM LAKE CITY THROUGH WABASHA AND ALMA ON MONDAY...AND ON TUESDAY FOR WINONA TO LA CROSSE. CRESTS WILL BE WEDNESDAY OR THURSDAY FROM GENOA THROUGH GUTTENBERG. FLOODING WILL REMAIN MINOR...THOUGH WINONA COULD GET CLOSE TO MODERATE FLOOD STAGE. REFER TO THE LATEST FLOOD STATEMENTS FOR DETAILS. NO LARGE RAIN AMOUNTS ARE ANTICIPATED UNTIL PERHAPS LATE TUESDAY NIGHT THROUGH THURSDAY NIGHT. THIS RAIN COULD SLOW THE RATE OF FALL OF THE MISSISSIPPI...BUT AT THIS TIME DOES NOT APPEAR AS IF IT WILL HAVE MUCH INFLUENCE ON THE CREST LEVEL. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...BOYNE SHORT TERM...AJ LONG TERM...AJ AVIATION...MW HYDROLOGY...MW/AJ