Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/08/14


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
855 PM MDT MON APR 7 2014 .UPDATE...MOST SHOWERS AND WINDS DECREASING AS EXPECTED WITH LOSS OF THE SUNS ENERGY...ONLY EXCEPTION IS OVER THE HIGH MOUNTAINS WHERE FAVORED NORTHWEST FLOW KEEPS SQUEEZING OUT MOISTURE. HAVE INCREASED POPS OF THE MOUNTAIN THROUGH MIDNIGHT WITH LESS THAN AN INCH ADDITIONAL ACCUMULATION. OTHERWISE...HAVE BLENDED IN OBSERVATIONS WITH FORECAST AND DECREASED SOME CLOUD COVER OVERNIGHT OVER THE PLAINS. && .AVIATION...WINDS EXPECTED TO CONTINUE TO VEER TO DRAINAGE DIRECTIONS WITHIN THE NEXT FEW HOURS. VFR CONDITIONS EXPECTED FOR THE NEXT 30 HOURS WITH NORTHWEST WINDS EXPECTED AGAIN TOMORROW...HOWEVER SPEEDS WILL STAY BELOW 10 KTS. && .PREV DISCUSSION... /ISSUED 341 PM MDT MON APR 7 2014/ SHORT TERM...FAIRLY STRONG NORTH NORTHWEST FLOW ALOFT CURRENTLY OVER THE REGION WITH UPPER TROUGH ACROSS THE NORTHERN AND CENTRAL PLAINS STATES AND UPPER RIDGE OVER THE GREAT BASIN. COMBINATION OF FAIRLY TIGHT NORTHERLY SURFACE GRADIENT AND GOOD MIXING CREATING STRONG WINDS ACROSS MUCH OF THE PLAINS...WITH SOME GUSTS TO 50 MPH FAR NORTHEAST CORNER. MOISTURE CONTINUES TO STREAM SOUTH OVER THE AREA...WITH RADAR SHOWING ISOLATED SHOWERS ACROSS THE PLAINS. AIRMASS UNSTABLE ENOUGH FOR FEW LIGHTNING STRIKES OVER EASTERN LINCOLN COUNTY DURING THE PAST HOUR. ACROSS MOUNTAINS...WEB CAMS INDICATING SCATTERED SNOW SHOWERS ALONG THE CONTINENTAL DIVIDE OF SUMMIT AND GRAND COUNTIES. MOISTURE TO DECREASE DURING THE EVENING AS DRIER SUBSIDENT AIR SPREADS INTO THE REGION. WITH THE AIRMASS STABILIZING AND BECOMING DRIER...THE ISOLATED SHOWERS ACROSS THE PLAINS SHOULD COME TO AN END SHORTLY AFTER SUNSET. LATEST RAP CROSS SECTIONS STILL INDICATE ENOUGH MOISTURE ACROSS THE MOUNTAINS THIS EVENING FOR A FEW LINGERING SNOW SHOWERS...BUT THESE SHOULD COME TO AN END BY MIDNIGHT. SURFACE GRADIENT WEAKENS DURING THE EVENING AS HIGH PRESSURE PUSHES SOUTH ONTO THE PLAINS. WITH THE AIRMASS STABILIZING...WINDS SHOULD BE ON THE DECREASE THOUGH IT WILL REMAIN A BIT GUSTY AT TIMES FAR EASTERN PLAINS. SKIES TO GRADUALLY CLEAR OVERNIGHT. ON TUESDAY...UPPER RIDGE OVER THE GREAT BASIN WILL BUILD INTO COLORADO WITH NORTHWEST FLOW ALOFT PREVAILING. THIS WILL BRING WARMER AND DRIER AIR INTO NORTHEAST AND NORTHCENTRAL COLORADO. TEMPERATURES TO WARM INTO THE 60S ACROSS THE PLAINS. LONG TERM...HIGH PRESSURE RIDGE...QG SUBSIDENCE AND GENERALLY DRY CONDITIONS WILL BE THE RULE TUESDAY NIGHT AND WEDNESDAY. LEE TROUGHING WILL BE GETTING UNDERWAY AS WELL DURING THIS TIME FRAME LEADING TO WARMER CONDITIONS EAST OF THE DIVIDE...ELEVATING FIRE DANGER WEDNESDAY AFTERNOON. NOT PLANNING ON HOISTING A FIRE WEATHER WATCH AT THIS TIME BUT CONDITIONS OVER THE NORTHEAST ZONES WILL NEED TO BE WATCHED FOR THIS. MODELS STILL WANT TO DRAG AN UPPER LEVEL TROUGH BY...MOSTLY TO OUR NORTH...FLATTENING THE RIDGE AND INCREASING THE GRADIENT ALOFT OVER COLORADO THURSDAY. ALL OF THIS SHOULD SERVE TO INCREASE THE WINDS A BIT...COOL TEMPERATURES SLIGHTLY AND BRING AN INCREASED THREAT OF PRECIPITATION TO THE AREA ON THURSDAY. THERE IS A BIT OF CAPE FORECAST IN THE MODELS THURSDAY AFTERNOON SO A RUMBLE OR TWO OF THUNDER IS NOT COMPLETELY OUT OF THE QUESTION THEN. MODERATE NORTHWEST FLOW ALOFT TO COVER COLORADO ON FRIDAY WITH A BIT OF AFTERNOON CONVECTION POSSIBLE OVER THE HIGH COUNTRY. ALL OF THE LONGER RANGE MODELS ARE STILL SUGGESTING A DECENT PRECIPITATION POTENTIAL FOR SOMETIME IN THE SATURDAY NIGHT TO SUNDAY TIME FRAME. AS PER USUAL THE DEVIL IS IN THE DETAILS. THERE ARE PLENTY OF TIMING AND STRENGTH DIFFERENCES IN THE MASS AND QG VERTICAL VELOCITY FIELDS BETWEEN THE CANADIAN...EUROPEAN ..DGEX AND GFS TO KEEP THE FORECAST PRETTY BROAD BRUSHED AT THIS POINT FOR THE WEEKEND. ODDLY ENOUGH THE SURFACE PRESSURE PATTERNS AMONGST THE AFOREMENTIONED MODELS ARE RATHER CONSISTENT WITH FRONTAL PASSAGE PERHAPS DURING THE DAY SATURDAY WITH A STRONG SHOT OF UPSLOPE THEREAFTER INTO SUNDAY. DEPENDING ON HOW THINGS EVENTUALLY PAN OUT...EFFECTS OF THIS SYSTEM COULD LINGER INTO MONDAY. AVIATION...GUSTY NORTHERLY WINDS CONTINUING ACROSS THE AREA AIRPORTS...A BIT MORE NORTHWEST AT KBJC. GUSTS AROUND 30 KTS COMMON...MAINLY AT KDEN. VFR CONDITIONS PREVAILING UNLIMITED CEILINGS AS SHOWERS WELL EAST OF DENVER. WINDS TO DECREASE BY 00Z THEN GRADUALLY SHIFT COUNTERCLOCKWISE WITH DRAINAGE PREVAILING BY 04Z. LATEST RAP IS HINTING THE WINDS WILL SHIFT CLOCKWISE TO THE SOUTHEAST BEFORE GOING TO DRAINAGE. FOR NOW WILL CONTINUE TO TREND CLOCKWISE TREND. WINDS TO THEN SHIFT TO THE NORTHWEST AFTER 15Z TUESDAY WITH SPEEDS AROUND 8 KTS. VFR TO CONTINUE. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...D-L LONG TERM....ET UPDATE/AVIATION...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1134 AM MDT SUN APR 6 2014 .UPDATE... ISSUED AT 901 AM MDT SUN APR 6 2014 ADJUSTED MOST POPS DOWNWARD FOR THE REMAINDER OF THE MORNING...ESPECIALLY OVER THE SOUTHEAST PLAINS...TO BETTER MATCH CURRENT RADAR TRENDS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 319 AM MDT SUN APR 6 2014 OUR CURRENT UPPER LEVEL SYSTEM IS NOW MOVING THROUGH NM...AND WILL SLOWLY MOVE EWD TODAY. SOME WEAK ENERGY ON THE BACKSIDE OF THE TROUGH WILL KEEP THE THREAT OF SHOWERS GOING THROUGH TONIGHT. SNOW SHOWERS CONTINUE THIS MORNING OVER THE ERN RANGES...WHILE SCT RAIN SHOWERS ARE STILL DEVELOPING OVER THE SERN PLAINS. SHORT TERM MODELS ARE IN DISAGREEMENT WITH HOW EXTENSIVE SHOWER ACTIVITY WILL BE THIS MORNING OVER OUR SERN CORNER...THE NAM HOLDS ON TO EXTENSIVE PRECIP WHILE THE HRRR DRIES THINGS OUT PRETTY QUICKLY. THE HRRR APPEARS TO BE A BIT TOO DRY WHILE THE NAM AND WRF MAY BE OVERDONE. WILL KEEP HIGH POPS OVER PROWERS...BACA...AND ERN LAS ANIMAS THIS MORNING...BUT AMTS DO NOT LOOK TOO IMPRESSIVE. SNOW LEVELS ARE CURRENTLY 6000-6500 FEET AND SHOULD REMAIN IN THE 7K FOOT RANGE TODAY. COLD AIR CONTINUES TO FILTER IN AND H7 TEMPS WILL FALL FROM AROUND MINUS 4 TO MINUS 8 OR SO BY MONDAY MORNING. BUT...PRECIP WILL BE WINDING DOWN OVERNIGHT...SO LOW ELEVATION SNOW POTENTIAL DOES NOT LOOK THAT GREAT. OVER THE MTS...PERSISTENT SHSN CONTINUE TODAY...AND WILL PICK UP IN INTENSITY AND COVERAGE THIS AFTERNOON AS INSTABILITY PEAKS. AMOUNTS GENERALLY LOOK UNDER ADVISORY LEVELS...SO WILL CANCEL THE CURRENT HIGHLIGHTS WITH THE MORNING ZONE PACKAGE. ANOTHER TWO TO FIVE INCHES POSSIBLE FOR THE HIGHER PEAKS THROUGH MONDAY MORNING. SOME ISOLD SHOWERS WILL CONTINUE THROUGH MONDAY MORNING...BUT WOULD NOT BE SURPRISED TO SEE SOME OVERNIGHT BREAKS IN THE CLOUDS...WHICH COULD LEAD TO SOME COLD MORNING LOWS LATER TONIGHT. ROSE .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 319 AM MDT SUN APR 6 2014 ON MONDAY...NORTHERLY FLOW WL BE FOUND OVR THE AREA. A PASSING DISTURBANCE AND SOME LINGERING MSTR WL MEAN POTENTIAL FOR ISOLD TO SCT SHOWERS ACRS MUCH OF THE AREA. HIGH TEMPS ON MON WL LIKELY BE A LITTLE BELOW AVERAGE. UPR RIDGING IS THEN EXPECTED OVR THE AREA FOR TUE AND WED...WITH DRY WEATHER AND WARMING TEMPS WITH MUCH ABOVE AVERAGE HIGHS BOTH DAYS. THE RIDGE GETS FLATTENED OVR THE AREA ON THU AS AN UPR TROF MOVES FROM THE NRN ROCKIES INTO THE NRN PLAINS STATES. SFC HIGH PRESSURE BACKS INTO THE SERN CO PLAINS ON THU...BRINGING LOW LEVEL UPSLOPE FLOW. THERE IS EXPECTED TO BE AN INCREASE IN MSTR OVR THE AREA...WITH THE POTENTIAL FOR SOME SHOWERS OVR THE MTNS AND ALONG THE I-25 CORRIDOR AND LOWER EAST SLOPES OF THE EASTERN MTNS WHERE THE UPSLOPE WL BE MOST PRONOUNCED. MAINLY DRY WEATHER IS THEN EXPECTED FOR FRI AS A WEAK UPR RIDGE MOVES OVR THE AREA. UNSETTLED WEATHER IS THEN EXPECTED FOR NEXT WEEKEND AS A BROAD UPR TROF MOVES OVR THE ROCKIES. THERE ARE SOME MODEL DIFFERENCES WITH REGARDS TO THE EXACT TRACK OF THE UPR TROF...BUT BOTH THE GFS AND ECMWF ARE SHOWING THE SYSTEM BRINGING PCPN AND COOLER TEMPS TO MOST OF THE AREA THRU THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1130 AM MDT SUN APR 6 2014 AFTER A SHORT LULL THIS MORNING...WILL SEE ISOLATED TO SCATTERED SHOWER ACTIVITY PICK UP AGAIN THIS AFTERNOON...THEN WIND DOWN SLOWLY OVERNIGHT. FZG LEVELS WILL GENERALLY 7500-8000 FEET TODAY...AND THE MTS WILL BECOME OBSCURED WITH SCT-NMRS SHOWERS. THERE COULD BE SOME SHOWERS NEAR THE TAF SITES TODAY...BUT THEY ARE NOT EXPECTED TO AFFECT FLIGHT CATEGORIES IN THE TAFS. ON MON...STILL SOME ISOLATED SHOWERS POSSIBLE OVER THE AREA IN THE MORNING BEFORE PRECIP SHIFTS EAST INTO KS DURING THE AFTERNOON. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PETERSEN SHORT TERM...ROSE LONG TERM...28 AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
904 AM MDT SUN APR 6 2014 .UPDATE... ISSUED AT 901 AM MDT SUN APR 6 2014 ADJUSTED MOST POPS DOWNWARD FOR THE REMAINDER OF THE MORNING...ESPECIALLY OVER THE SOUTHEAST PLAINS...TO BETTER MATCH CURRENT RADAR TRENDS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 319 AM MDT SUN APR 6 2014 OUR CURRENT UPPER LEVEL SYSTEM IS NOW MOVING THROUGH NM...AND WILL SLOWLY MOVE EWD TODAY. SOME WEAK ENERGY ON THE BACKSIDE OF THE TROUGH WILL KEEP THE THREAT OF SHOWERS GOING THROUGH TONIGHT. SNOW SHOWERS CONTINUE THIS MORNING OVER THE ERN RANGES...WHILE SCT RAIN SHOWERS ARE STILL DEVELOPING OVER THE SERN PLAINS. SHORT TERM MODELS ARE IN DISAGREEMENT WITH HOW EXTENSIVE SHOWER ACTIVITY WILL BE THIS MORNING OVER OUR SERN CORNER...THE NAM HOLDS ON TO EXTENSIVE PRECIP WHILE THE HRRR DRIES THINGS OUT PRETTY QUICKLY. THE HRRR APPEARS TO BE A BIT TOO DRY WHILE THE NAM AND WRF MAY BE OVERDONE. WILL KEEP HIGH POPS OVER PROWERS...BACA...AND ERN LAS ANIMAS THIS MORNING...BUT AMTS DO NOT LOOK TOO IMPRESSIVE. SNOW LEVELS ARE CURRENTLY 6000-6500 FEET AND SHOULD REMAIN IN THE 7K FOOT RANGE TODAY. COLD AIR CONTINUES TO FILTER IN AND H7 TEMPS WILL FALL FROM AROUND MINUS 4 TO MINUS 8 OR SO BY MONDAY MORNING. BUT...PRECIP WILL BE WINDING DOWN OVERNIGHT...SO LOW ELEVATION SNOW POTENTIAL DOES NOT LOOK THAT GREAT. OVER THE MTS...PERSISTENT SHSN CONTINUE TODAY...AND WILL PICK UP IN INTENSITY AND COVERAGE THIS AFTERNOON AS INSTABILITY PEAKS. AMOUNTS GENERALLY LOOK UNDER ADVISORY LEVELS...SO WILL CANCEL THE CURRENT HIGHLIGHTS WITH THE MORNING ZONE PACKAGE. ANOTHER TWO TO FIVE INCHES POSSIBLE FOR THE HIGHER PEAKS THROUGH MONDAY MORNING. SOME ISOLD SHOWERS WILL CONTINUE THROUGH MONDAY MORNING...BUT WOULD NOT BE SURPRISED TO SEE SOME OVERNIGHT BREAKS IN THE CLOUDS...WHICH COULD LEAD TO SOME COLD MORNING LOWS LATER TONIGHT. ROSE .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 319 AM MDT SUN APR 6 2014 ON MONDAY...NORTHERLY FLOW WL BE FOUND OVR THE AREA. A PASSING DISTURBANCE AND SOME LINGERING MSTR WL MEAN POTENTIAL FOR ISOLD TO SCT SHOWERS ACRS MUCH OF THE AREA. HIGH TEMPS ON MON WL LIKELY BE A LITTLE BELOW AVERAGE. UPR RIDGING IS THEN EXPECTED OVR THE AREA FOR TUE AND WED...WITH DRY WEATHER AND WARMING TEMPS WITH MUCH ABOVE AVERAGE HIGHS BOTH DAYS. THE RIDGE GETS FLATTENED OVR THE AREA ON THU AS AN UPR TROF MOVES FROM THE NRN ROCKIES INTO THE NRN PLAINS STATES. SFC HIGH PRESSURE BACKS INTO THE SERN CO PLAINS ON THU...BRINGING LOW LEVEL UPSLOPE FLOW. THERE IS EXPECTED TO BE AN INCREASE IN MSTR OVR THE AREA...WITH THE POTENTIAL FOR SOME SHOWERS OVR THE MTNS AND ALONG THE I-25 CORRIDOR AND LOWER EAST SLOPES OF THE EASTERN MTNS WHERE THE UPSLOPE WL BE MOST PRONOUNCED. MAINLY DRY WEATHER IS THEN EXPECTED FOR FRI AS A WEAK UPR RIDGE MOVES OVR THE AREA. UNSETTLED WEATHER IS THEN EXPECTED FOR NEXT WEEKEND AS A BROAD UPR TROF MOVES OVR THE ROCKIES. THERE ARE SOME MODEL DIFFERENCES WITH REGARDS TO THE EXACT TRACK OF THE UPR TROF...BUT BOTH THE GFS AND ECMWF ARE SHOWING THE SYSTEM BRINGING PCPN AND COOLER TEMPS TO MOST OF THE AREA THRU THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 319 AM MDT SUN APR 6 2014 ISOLD TO SCT SHOWERS WILL CONTINUE TODAY OVER MUCH OF SERN CO. AFTER A SHORT LULL THIS MORNING...WILL SEE SHOWER ACTIVITY PICK UP AGAIN FOR THE AFTERNOON...THEN WIND DOWN SLOWLY OVERNIGHT. FZG LEVELS WILL GENERALLY 7500-8000 FEET TODAY...AND THE MTS WILL CONTINUE TO BE OBSCD WITH SCT-NRMS SHOWERS. THERE COULD BE SOME SHOWERS VC THE TAF SITES TODAY...BUT THEY ARE NOT EXPECTED TO AFFECT FLIGHT CATEGORIES IN THE TAFS. MAIN SHORT TERM CONCERN WILL BE AT KALS...WHICH SAW SOME LIGHT SHSN OVERNIGHT...AND THIS COULD LEAD TO SOME PC MORNING FG OR BR FOR THE EARLY MORNING HOURS. ROSE && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PETERSEN SHORT TERM...ROSE LONG TERM...28 AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
322 AM MDT SUN APR 6 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 319 AM MDT SUN APR 6 2014 OUR CURRENT UPPER LEVEL SYSTEM IS NOW MOVING THROUGH NM...AND WILL SLOWLY MOVE EWD TODAY. SOME WEAK ENERGY ON THE BACKSIDE OF THE TROUGH WILL KEEP THE THREAT OF SHOWERS GOING THROUGH TONIGHT. SNOW SHOWERS CONTINUE THIS MORNING OVER THE ERN RANGES...WHILE SCT RAIN SHOWERS ARE STILL DEVELOPING OVER THE SERN PLAINS. SHORT TERM MODELS ARE IN DISAGREEMENT WITH HOW EXTENSIVE SHOWER ACTIVITY WILL BE THIS MORNING OVER OUR SERN CORNER...THE NAM HOLDS ON TO EXTENSIVE PRECIP WHILE THE HRRR DRIES THINGS OUT PRETTY QUICKLY. THE HRRR APPEARS TO BE A BIT TOO DRY WHILE THE NAM AND WRF MAY BE OVERDONE. WILL KEEP HIGH POPS OVER PROWERS...BACA...AND ERN LAS ANIMAS THIS MORNING...BUT AMTS DO NOT LOOK TOO IMPRESSIVE. SNOW LEVELS ARE CURRENTLY 6000-6500 FEET AND SHOULD REMAIN IN THE 7K FOOT RANGE TODAY. COLD AIR CONTINUES TO FILTER IN AND H7 TEMPS WILL FALL FROM AROUND MINUS 4 TO MINUS 8 OR SO BY MONDAY MORNING. BUT...PRECIP WILL BE WINDING DOWN OVERNIGHT...SO LOW ELEVATION SNOW POTENTIAL DOES NOT LOOK THAT GREAT. OVER THE MTS...PERSISTENT SHSN CONTINUE TODAY...AND WILL PICK UP IN INTENSITY AND COVERAGE THIS AFTERNOON AS INSTABILITY PEAKS. AMOUNTS GENERALLY LOOK UNDER ADVISORY LEVELS...SO WILL CANCEL THE CURRENT HIGHLIGHTS WITH THE MORNING ZONE PACKAGE. ANOTHER TWO TO FIVE INCHES POSSIBLE FOR THE HIGHER PEAKS THROUGH MONDAY MORNING. SOME ISOLD SHOWERS WILL CONTINUE THROUGH MONDAY MORNING...BUT WOULD NOT BE SURPRISED TO SEE SOME OVERNIGHT BREAKS IN THE CLOUDS...WHICH COULD LEAD TO SOME COLD MORNING LOWS LATER TONIGHT. ROSE .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 319 AM MDT SUN APR 6 2014 ON MONDAY...NORTHERLY FLOW WL BE FOUND OVR THE AREA. A PASSING DISTURBANCE AND SOME LINGERING MSTR WL MEAN POTENTIAL FOR ISOLD TO SCT SHOWERS ACRS MUCH OF THE AREA. HIGH TEMPS ON MON WL LIKELY BE A LITTLE BELOW AVERAGE. UPR RIDGING IS THEN EXPECTED OVR THE AREA FOR TUE AND WED...WITH DRY WEATHER AND WARMING TEMPS WITH MUCH ABOVE AVERAGE HIGHS BOTH DAYS. THE RIDGE GETS FLATTENED OVR THE AREA ON THU AS AN UPR TROF MOVES FROM THE NRN ROCKIES INTO THE NRN PLAINS STATES. SFC HIGH PRESSURE BACKS INTO THE SERN CO PLAINS ON THU...BRINGING LOW LEVEL UPSLOPE FLOW. THERE IS EXPECTED TO BE AN INCREASE IN MSTR OVR THE AREA...WITH THE POTENTIAL FOR SOME SHOWERS OVR THE MTNS AND ALONG THE I-25 CORRIDOR AND LOWER EAST SLOPES OF THE EASTERN MTNS WHERE THE UPSLOPE WL BE MOST PRONOUNCED. MAINLY DRY WEATHER IS THEN EXPECTED FOR FRI AS A WEAK UPR RIDGE MOVES OVR THE AREA. UNSETTLED WEATHER IS THEN EXPECTED FOR NEXT WEEKEND AS A BROAD UPR TROF MOVES OVR THE ROCKIES. THERE ARE SOME MODEL DIFFERENCES WITH REGARDS TO THE EXACT TRACK OF THE UPR TROF...BUT BOTH THE GFS AND ECMWF ARE SHOWING THE SYSTEM BRINGING PCPN AND COOLER TEMPS TO MOST OF THE AREA THRU THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 319 AM MDT SUN APR 6 2014 ISOLD TO SCT SHOWERS WILL CONTINUE TODAY OVER MUCH OF SERN CO. AFTER A SHORT LULL THIS MORNING...WILL SEE SHOWER ACTIVITY PICK UP AGAIN FOR THE AFTERNOON...THEN WIND DOWN SLOWLY OVERNIGHT. FZG LEVELS WILL GENERALLY 7500-8000 FEET TODAY...AND THE MTS WILL CONTINUE TO BE OBSCD WITH SCT-NRMS SHOWERS. THERE COULD BE SOME SHOWERS VC THE TAF SITES TODAY...BUT THEY ARE NOT EXPECTED TO AFFECT FLIGHT CATEGORIES IN THE TAFS. MAIN SHORT TERM CONCERN WILL BE AT KALS...WHICH SAW SOME LIGHT SHSN OVERNIGHT...AND THIS COULD LEAD TO SOME PC MORNING FG OR BR FOR THE EARLY MORNING HOURS. ROSE && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ROSE LONG TERM...28 AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS ALBANY NY
951 PM EDT MON APR 7 2014 .SYNOPSIS... AS A STORM SYSTEM MOVES ACROSS THE REGION...A STEADY LIGHT RAIN IS EXPECTED THIS EVENING THROUGH THE OVERNIGHT HOURS. WINDS WILL BE GUSTY AT TIMES...ESPECIALLY IN THE HUDSON VALLEY AND ACROSS WESTERN NEW ENGLAND. ALTHOUGH STEADY RAIN WILL END BY TOMORROW MORNING...THERE WILL CONTINUE TO BE A CHANCE FOR SHOWERS THROUGH THE DAY TOMORROW...ESPECIALLY ACROSS THE HIGH TERRAIN...ALONG WITH GUSTY WESTERLY WINDS. DRY WEATHER WILL RETURN FOR WEDNESDAY AND THURSDAY WITH MILD TEMPERATURES ALSO RETURNING BY LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 945 PM EDT... RAIN SHOWERS AND DRIZZLE IMPACT AREAS AROUND THE IMMEDIATE CAPITAL REGION AND POINTS NORTH AND EAST OF THE IMMEDIATE CAPITAL REGION AS THE RAINFALL AHEAD OF A NORTHWARD MOVING COLD FRONT EXITS THE REGION. IN CONJUNCTION WITH THE PROGRESSION OF THE WARM FRONT...THE UPPER LEVELS SHOW A NARROW DRY SLOT MOVING NORTHEAST INTO THE REGION FROM CENTRAL PENNSYLVANIA THAT WILL TEMPORARILY PROVIDE ISOLATED SHOWERS AND DRIZZLE ACROSS THE REGION. MORE WIDELY SCATTERED SHOWERS WILL MOVE THROUGH AFTER 06Z AS THE UPPER LEVEL ENERGY MOVES EAST INTO THE REGION. LOW TEMPERATURES BASED OFF OF 9 PM OBSERVATIONS HAVE TEMPERATURES ALREADY IN THE MID 30S ACROSS THE WESTERN AREAS AS SHALLOW COLD AIR AHEAD OF THE WARM FRONT HAS BEEN IN PLACE ACROSS THE REGION. WE HAVE ADJUSTED LOW TEMPERATURES BASED OFF OF THESE TRENDS...HOWEVER AS THE WARM FRONT APPROACHES...TEMPERATURES WILL BEGIN TO RISE INTO THE MID 40S ACROSS THE REGION DURING THE OVERNIGHT HOURS. A STEADY SOUTH TO SOUTHEASTERLY FLOW ALONG THE INFLUX OF MOISTURE AHEAD OF THE UPPER LEVEL ENERGY WILL CAUSE WINDS TO GUST NEAR 30 TO 35 KNOTS AT TIMES AS WE GO INTO THE OVERNIGHT HOURS...ESPECIALLY AS WE GO INTO THE HIGHEST TERRAIN OF WESTERN NEW ENGLAND. FOR NOW...NO HEADLINES FOR WINDS BUT DID INCREASE GUST POTENTIAL INTO THESE AREAS. PREV DISC... AS OF 426 PM EDT...A SIGNIFICANT STORM IS IN PROGRESS ACROSS THE EASTERN HALF OF THE COUNTRY WITH WIDESPREAD SEVERE WEATHER AND FLASH FLOODING ACROSS THE SOUTHEAST AND GULF COAST REGION. SFC LOW PRESSURE WAS SITUATED NEAR LOUISVILLE KENTUCKY...AND WAS CONTINUING TO RAPIDLY MOVE NORTHEAST TOWARDS THE EASTERN GREAT LAKES. AT THE SAME TIME...A SURFACE WARM FRONT WAS DRAPED ACROSS THE MID ATLANTIC REGION. THIS WARM FRONT WAS MOVING NORTHWARD...AS DEPICTED BY THE 3 HR PRESSURE FALLS OF NEARLY 7 MB OVER THE NORTHERN CHESAPEAKE BAY REGION. STRONG ISENTROPIC LIFT WAS ALLOWING FOR AN AREA OF LIGHT RAIN OVER MUCH OF CENTRAL PA AND WESTERN/CENTRAL NY. ANOTHER ORGANIZED AREA OF RAINFALL WAS NEAR THE STORM/S TRIPLE POINT...AIDED BY A COASTAL FRONT...ACROSS THE MID ATLANTIC REGION. BOTH OF THESE AREAS OF RAINFALL WILL MOVE NORTHEAST THROUGH THE EVENING HOURS. AS A RESULT...LIGHT RAIN WILL BREAK OUT ACROSS OUR ENTIRE AREA BY LATER THIS EVENING...WITH THE STEADIEST RAINFALL ACROSS BOTH THE NORTHWESTERN AND SOUTHEASTERN CORNERS OF THE AREA DUE TO TWO AFOREMENTIONED AREAS OF RAINFALL. WHILE EVERYWHERE IS EXPECTED TO SEE SOME RAIN TONIGHT...THE HEAVIEST TOTALS WILL BE ACROSS THE WESTERN ADIRONDACKS...AS WELL AS THE EASTERN CATSKILLS...MID HUDSON VALLEY...NW CT...AND BERKSHIRES. PLEASE SEE OUR HYDRO DISCUSSION ON HOW WE EXPECT THIS RAINFALL TO IMPACT OUR HSA. THE 17Z 3KM HRRR SHOWS MOST OF THIS RAINFALL BEFORE 2 AM...BEFORE IT STARTS TO BECOME MORE SHOWERY IN NATURE. ANOTHER COMPONENT TO THIS SYSTEM WILL BE THE POTENTIAL FOR STRONG GUSTY WINDS. THE LOW LEVEL FLOW CONTINUES TO BE OUT OF THE S-SE AND RATHER GUSTY AT TIMES. THERE ARE SOME STRONG WINDS NOT FAR OFF THE SURFACE...AS BOTH THE NAM/GFS SHOW 925 HPA WINDS OF 35-55 KTS FOR A BRIEF PERIOD THIS EVENING IN ADVANCE OF THE STORM. WHILE IT WILL PROBABLY BE TOUGH TO MIX THESE DOWN CONSIDERING THE EXPECTED RAINFALL...ELEVATED AREAS...SUCH AS ACROSS THE TACONICS AND MOUNTAINS OF WESTERN NEW ENGLAND HAVE THE POTENTIAL TO SEE SOME GUSTY WINDS. THIS IS ESPECIALLY TRUE BETWEEN THE SRN GREENS AND NORTHERN BERKSHIRES...WHERE E-SE FLOW HAS BEEN KNOWN TO CHANNEL EASILY AND PRODUCE STRONG WINDS. AT THIS POINT...THERE STILL IS TOO MUCH UNCERTAINTY REGARDING THE EXTENT/COVERAGE OF ANY STRONG WINDS TO ISSUE A WIND ADVISORY OR HIGH WIND WARNING...BUT WE WILL MENTION IT IN OUR HWO STATEMENT...AND HAVE COVERED FOR WIND GUSTS OF 35-40 MPH IN OUR CURRENT FORECAST. TOWARDS DAYBREAK...THE STORM/S OCCLUDED FRONT WILL BE NEARING OUR REGION FROM THE WEST. WE PROBABLY WON/T MAKE IT INTO THE STORM/S WARM SECTOR AS THE TRIPLE POINT WILL REMAIN TO OUR SOUTH. STILL...SHOWALTER VALUES WILL BE CLOSE TO ZERO...SO AN ISOLATED RUMBLE OF THUNDER DUE TO SOME ELEVATED CONVECTION CANNOT TOTALLY BE RULED OUT. MIN TEMPS TONIGHT WILL LIKELY BE DURING THE LATE EVENING...AS TEMPS WET BULB DUE TO THE RAINFALL...AND THEN HOLD STEADY OR EVEN RISE SLIGHTLY FOR THE LATE NIGHT HOURS. MOST AREAS WILL FALL INTO THE UPPER 30S TO MID 40S. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE STORM/S OCCLUDED FRONT WILL BE MOVING THROUGH EARLY IN THE DAY WITH A BAND OF RAIN SHOWERS. AFTER THAT...WINDS WILL SWITCH TO A W-SW DIRECTION DURING THE MORNING HOURS...AS THE SFC LOW PASSES NORTH OF THE REGION ACROSS THE ST. LAWRENCE VALLEY. DESPITE BEING BEHIND THE STORM...COOLER AIR MOVING IN ALOFT WILL ALLOW FOR GOOD MIXING...WHICH WILL ALLOW FOR TEMPS TO BE MILD ON TUESDAY. TEMPS WILL RANGE FROM THE UPPER 40S IN THE ADIRONDACKS AND CATSKILLS TO THE MID 50S TO MID 60S FOR VALLEY AREAS. WITH THE UPPER LEVEL SHORTWAVE STILL MOVING ACROSS THE REGION...THERE WILL CONTINUE TO BE A GOOD AMOUNT OF CLOUDS AROUND...ESP FOR CENTRAL/NORTHERN PARTS OF THE AREA. SOME BREAKS OF SUN LOOK POSSIBLE BY LATE IN THE DAY. THERE MAY EVEN BE A FEW LINGERING RAIN SHOWERS...MAINLY FOR THE MOHAWK VALLEY/ADIRONDACKS AND SOUTHERN VERMONT...ALTHOUGH THESE SHOULD BE RATHER LIGHT. THE GOOD MIXING /TO ABOUT 800-850 HPA BASED ON THE LATEST 12Z GFS/NAM BUFKIT SOUNDINGS/ WILL ALLOW FOR SOME GUSTY WEST TO SOUTHWEST WINDS...ESP FOR THE MOHAWK VALLEY...CAPITAL REGION AND BERKSHIRES. WINDS MAY GUST 25-35 MPH AT TIMES DURING THE AFTN AND EARLY EVENING HOURS. WINDS WILL START TO DIMINISH FOR TUESDAY NIGHT BUT LIKELY STILL BE RATHER BRISK. OTHERWISE...SKIES WILL BE PARTLY TO MOSTLY CLOUDY...WITH THE MOST CLOUDS ACROSS THE ADIRONDACKS AND SRN GREENS. THERE MAY BE SOME RAIN OR SNOW SHOWERS OVER THE HIGH TERRAIN AS ANOTHER FAST MOVING UPPER LEVEL SHORTWAVE MOVES ACROSS SOUTHERN CANADA...BUT VALLEY AREAS SHOULD BE FAIRLY QUIET. MIN TEMPS WILL RANGE FROM THE MID 20S TO THE MID 30S. ASIDE FROM A MORNING SNOW/RAIN SHOWER OVER THE WESTERN ADIRONDACKS...IT LOOKS DRY FOR WEDNESDAY INTO WEDNESDAY NIGHT...AS HIGH PRESSURE BUILDS INTO THE EASTERN PORTION OF THE CONUS FROM THE PLAINS. IT STILL MAY BE A LITTLE BREEZY DURING DAYTIME MIXING ON WEDNESDAY AFTN. BEHIND THE DEPARTING SHORTWAVE...TEMPS ALOFT WILL BE A LITTLE COOLER FOR WEDNESDAY /850 HPA TEMPS AROUND -4 TO -8 DEGREES C/...SO MAX TEMPS WILL ONLY REACH THE UPPER 30S TO MID 50S OVER THE REGION. CLEAR SKIES AND LIGHT WINDS WILL ALLOW FOR COOL TEMPS ON WED NIGHT...WITH 20S EVERYWHERE. && .LONG TERM /THURSDAY THROUGH MONDAY/... DURING MOST OF THIS LONG TERM PERIOD OF THE FORECAST...THE WESTERLIES ARE EXPECTED TO BE QUITE ACTIVE AND REMAIN ALONG OR JUST NORTH OF THE U.S./CANADIAN BORDER. THE RESULT FOR OUR REGION WILL BE A GRADUAL INCREASE IN TEMPERATURES THROUGH THE PERIOD. THURSDAY INTO THURSDAY NIGHT... A RATHER STRONG UPPER LEVEL JET AND SURFACE CYCLONE WILL TRACK JUST NORTH OF THE U.S./CANADIAN BORDER WITH ITS ASSOCIATED COLD FRONT TRAILING ACROSS THE GREAT LAKES REGION AND MIGRATING EASTWARD. DUE TO THE UPPER JET CURVATURE...SEEMS MOST OF THE PRECIP THAT DOES OCCUR WILL BE POST-FRONTAL WHILE THE MAIN SUPPORT BECOMES FURTHER REMOVED. WE WILL KEEP POPS INTO THE CHC-SCT VALUES AND BLEND THE LATEST MOS VALUES FROM THE ECMWF/GFS. FRIDAY... THERE IS A TENDENCY FROM THE GLOBAL MODELS THAT ANOTHER UPPER LEVEL WAVE WILL INTERACT WITH THE SURFACE COLD FRONT ACROSS THE OHIO VALLEY. EITHER A WEAK WAVE DEVELOPS ALONG THE BOUNDARY /AS SUGGESTED BY THE THE GFS/ OR A MORE PROGRESSIVE NATURE AS SUGGESTED BY THE ECMWF/GGEM WHICH WOULD KEEP OUR SOUTHERN ZONES DRY. FOR NOW...WE WILL LEAN TOWARD THE DRIER SCENARIO FOR OUR SOUTHERN ZONES. SEASONABLE TEMPERATURES ARE EXPECTED WITH SLIGHTLY COOLER VALUES ACROSS THE ADIRONDACKS. FRIDAY NIGHT INTO SUNDAY... GLOBAL MODELS CONTINUE TO INCREASE CONFIDENCE THAT A SUBTROPICAL RIDGE WILL STRENGTHEN OFF THE SOUTHEAST CONUS WHILE A TROUGH AMPLIFIES OVER THE CENTER OF THE NATION AS A POTENT WAVES DIVES SOUTHWARD ACROSS THE BRITISH COLUMBIA COAST. THE NET RESULT WOULD BE TO SLOW DOWN THE FORWARD PROGRESS OF SURFACE FEATURES AND ALLOW WARM ADVECTION TO OVERSPREAD MOST OF THE EASTERN CONUS. AS H850 TEMPS CLIMB TOWARD +10C AND STRENGTHEN SOUTHWEST FLOW...AFTERNOON HIGH TEMPERATURES SHOULD EASILY CLIMB WELL INTO THE 60S WITH A GRADUAL INCREASE OF OVERNIGHT LOWS FROM THE 30S FRIDAY NIGHT AND WELL INTO THE 40S FOR MANY LOCATIONS SATURDAY NIGHT. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... RAIN SHOWERS AND LOWERING CIGS WILL CONTINUE THROUGH THE NIGHT. MAIN CHALLENGE WILL BE LLWS AS LATEST HI-RESOLUTION MODELS SUGGEST AT OR ABOVE 2K FEET THOSE WIND MAGNITUDES INCREASE TO BETWEEN 40-50KTS. SO WE WILL EXPAND THE LLWS FORECAST TO ALL TAF LOCATIONS TONIGHT. OTHERWISE...MAINLY MVFR CONDITIONS ARE EXPECTED IN BOTH VISIBILITY AND CIGS. CONDITIONS IMPROVE TOWARD SUNRISE TUESDAY AS DRY SLOT BECOMES WELL ENTRENCHED ACROSS THE REGION. COLD FRONT REMAINS UPSTREAM AS ADDITIONAL SHOWERS ARE EXPECTED BUT THE PROBABILITIES AT THIS TIME SEEM A BIT LOW...HENCE THE PROB30 FOR THE AFTERNOON HOURS. WINDS WILL HAVE SHIFTED TOWARD THE SOUTH TO SOUTHWEST AND AN INCREASE IN SUSTAINED WINDS AT OR JUST ABOVE 10KTS WITH GUSTS NEAR 20KTS ARE EXPECTED...ESPECIALLY IN SHOWERS. OUTLOOK... TUESDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. WEDNESDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... STRONG WINDS ARE EXPECTED OVER THE NEXT SEVERAL DAYS... RH VALUES WILL BE BELOW 30 PERCENT ON WEDNESDAY AND THURSDAY... AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE REGION TONIGHT INTO TOMORROW...BRINGING A WIDESPREAD WETTING RAIN TO THE REGION. THE HEAVIEST RAINFALL WILL BE ACROSS THE ADIRONDACKS AND ACROSS FAR SOUTHEASTERN PARTS OF THE AREA. MANY HIGH TERRAIN AREAS CONTINUE TO HAVE A SNOW PACK IN PLACE. ALTHOUGH RH VALUES WILL BE HIGH THIS EVENING INTO TONIGHT...RH VALUES WILL LOWER TO 35 TO 50 PERCENT BEHIND THE STORM FOR TOMORROW. RH VALUES WILL BE AS LOW AS 25 PERCENT DURING THE AFTERNOON HOURS ON WEDNESDAY AND THURSDAY. WINDS WILL BE SIGNIFICANT OVER THE NEXT SEVERAL DAYS. S-SE WINDS WILL BE GUSTY THIS EVENING INTO TONIGHT..ESP ACROSS WESTERN NEW ENGLAND WITH GUSTS OVER 40 MPH POSSIBLE. BEHIND THE STORM SYSTEM...W-NW WINDS WILL BE VERY STRONG DURING DAYTIME MIXING TOMORROW AFTN...WITH GUSTS OVER 25 MPH POSSIBLE...ESP IN AREAS THAT CHANNEL WESTERLY FLOW. WINDS WILL CONTINUE BE GUSTY DURING DAYTIME MIXING ON WEDNESDAY WITH GUSTS AROUND 25 MPH POSSIBLE...INCLUDING DURING THE TIME WHEN RH VALUES ARE EXPECTED TO BE VERY LOW. && .HYDROLOGY... RIVER FLOODING CANNOT BE RULED OUT OVER THE NEXT FEW DAYS... AN AREA OF LOW PRESSURE WILL BRING A STEADY LIGHT TO MODERATE RAINFALL TO THE REGION TONIGHT INTO TOMORROW MORNING. THE HEAVIEST RAINFALL WILL BE ACROSS THE ADIRONDACKS...AND ACROSS FAR SOUTHEASTERN PARTS OF THE AREA. WITHIN THESE AREAS...RAINFALL AMOUNTS OF THREE QUARTERS OF AN INCH TO AN INCH AND A QUARTER LOOK TO OCCUR...WITH LOCALLY HIGHER TOTALS POSSIBLE. ELSEWHERE...BASIN RAINFALL AMOUNTS WILL BE A QUARTER TO THREE QUARTERS OF AN INCH. WITH SNOW CONTINUING TO MELT OUT OF THE HIGHEST TERRAIN...THIS WILL LEAD TO SIGNIFICANT RUNOFF...RESULTING IN SHARP RISES ON RIVERS AND STREAMS. WITH THE STEADY RAINFALL LATER THIS EVENING INTO TONIGHT...PONDING OF WATER ON ROADWAYS IS LIKELY...WITH SOME MINOR FLOODING OF POOR DRAINAGE OR URBAN AREAS POSSIBLE AS WELL. THE NERFC CURRENTLY SHOWS SEVERAL RIVERS COMING CLOSE TO BANKFULL BY LATE TONIGHT AND INTO THE DAY ON TUESDAY. IF MORE RAINFALL THAN ANTICIPATED OCCURS OR IF MORE SNOWMELT HAPPENS...THIS COULD RESULT IN MINOR FLOODING ON SOME RIVERS...SUCH AS THE SACANDAGA RIVER IN THE ADIRONDACKS...AS WELL AS PARTS OF THE HOOSIC...METTAWEE...AND HOUSATONIC RIVERS. IN ADDITION...SOME RESERVOIRS AND LAKE WILL BE FILLING UP...AND MINOR FLOODING IS POSSIBLE BY THE MID WEEK PERIOD AT DELTA RESERVOIR ON THE FAR UPPER MOHAWK RIVER. ALTHOUGH MOST RIVERS AND STREAMS ARE FREE OF ICE...THERE ARE SOME RIVERS AND STREAMS ACROSS THE ADIRONDACKS THAT ARE STILL ICE COVERED. WITH RISING LEVELS DUE TO THE RAINFALL AND SNOW MELT...THIS COULD RESULT IN AN ISOLATED ICE JAM BETWEEN TONIGHT AND TOMORROW. RIVERS SHOULD START TO RECEDE DURING THE MID WEEK PERIOD WITH DRY WEATHER ANTICIPATED FOR WEDNESDAY AND THURSDAY. HOWEVER...AN APPROACHING COLD FRONT WILL RETURN THE THREAT OF LIGHT RAIN SHOWERS TO THE REGION FOR FRIDAY. 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...FRUGIS NEAR TERM...FRUGIS/LFM/BGM SHORT TERM...FRUGIS LONG TERM...BGM AVIATION...IAA/BGM FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
827 PM EDT MON APR 7 2014 .SYNOPSIS... AS A STORM SYSTEM MOVES ACROSS THE REGION...A STEADY LIGHT RAIN IS EXPECTED THIS EVENING THROUGH THE OVERNIGHT HOURS. WINDS WILL BE GUSTY AT TIMES...ESPECIALLY IN THE HUDSON VALLEY AND ACROSS WESTERN NEW ENGLAND. ALTHOUGH STEADY RAIN WILL END BY TOMORROW MORNING...THERE WILL CONTINUE TO BE A CHANCE FOR SHOWERS THROUGH THE DAY TOMORROW...ESPECIALLY ACROSS THE HIGH TERRAIN...ALONG WITH GUSTY WESTERLY WINDS. DRY WEATHER WILL RETURN FOR WEDNESDAY AND THURSDAY WITH MILD TEMPERATURES ALSO RETURNING BY LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 800 PM EDT... RAIN CONTINUES TO OVERSPREAD THE REGION WITH STRONG ISENTROPIC ASCENT. HOWEVER...SEEMS THE DRIER AIR IS WINNING OUT BOTH AT THE SURFACE AND ALOFT WITH RADAR IMAGERY NOW REVEALING A BIT MORE SHOWERY SO IT SEEMS THIS MAY BE A QUICKER EVENT UNFOLDING. DUE TO THE QUICK NATURE...WE CONTINUE TO MONITOR THE WINDS ALOFT AND ITS IMPACTS INTO THE BERKS AND TACONICS. FOR NOW...NO HEADLINES FOR WINDS BUT DID INCREASE GUST POTENTIAL INTO THESE AREAS. PREV DISC... AS OF 426 PM EDT...A SIGNIFICANT STORM IS IN PROGRESS ACROSS THE EASTERN HALF OF THE COUNTRY WITH WIDESPREAD SEVERE WEATHER AND FLASH FLOODING ACROSS THE SOUTHEAST AND GULF COAST REGION. SFC LOW PRESSURE WAS SITUATED NEAR LOUISVILLE KENTUCKY...AND WAS CONTINUING TO RAPIDLY MOVE NORTHEAST TOWARDS THE EASTERN GREAT LAKES. AT THE SAME TIME...A SURFACE WARM FRONT WAS DRAPED ACROSS THE MID ATLANTIC REGION. THIS WARM FRONT WAS MOVING NORTHWARD...AS DEPICTED BY THE 3 HR PRESSURE FALLS OF NEARLY 7 MB OVER THE NORTHERN CHESAPEAKE BAY REGION. STRONG ISENTROPIC LIFT WAS ALLOWING FOR AN AREA OF LIGHT RAIN OVER MUCH OF CENTRAL PA AND WESTERN/CENTRAL NY. ANOTHER ORGANIZED AREA OF RAINFALL WAS NEAR THE STORM/S TRIPLE POINT...AIDED BY A COASTAL FRONT...ACROSS THE MID ATLANTIC REGION. BOTH OF THESE AREAS OF RAINFALL WILL MOVE NORTHEAST THROUGH THE EVENING HOURS. AS A RESULT...LIGHT RAIN WILL BREAK OUT ACROSS OUR ENTIRE AREA BY LATER THIS EVENING...WITH THE STEADIEST RAINFALL ACROSS BOTH THE NORTHWESTERN AND SOUTHEASTERN CORNERS OF THE AREA DUE TO TWO AFOREMENTIONED AREAS OF RAINFALL. WHILE EVERYWHERE IS EXPECTED TO SEE SOME RAIN TONIGHT...THE HEAVIEST TOTALS WILL BE ACROSS THE WESTERN ADIRONDACKS...AS WELL AS THE EASTERN CATSKILLS...MID HUDSON VALLEY...NW CT...AND BERKSHIRES. PLEASE SEE OUR HYDRO DISCUSSION ON HOW WE EXPECT THIS RAINFALL TO IMPACT OUR HSA. THE 17Z 3KM HRRR SHOWS MOST OF THIS RAINFALL BEFORE 2 AM...BEFORE IT STARTS TO BECOME MORE SHOWERY IN NATURE. ANOTHER COMPONENT TO THIS SYSTEM WILL BE THE POTENTIAL FOR STRONG GUSTY WINDS. THE LOW LEVEL FLOW CONTINUES TO BE OUT OF THE S-SE AND RATHER GUSTY AT TIMES. THERE ARE SOME STRONG WINDS NOT FAR OFF THE SURFACE...AS BOTH THE NAM/GFS SHOW 925 HPA WINDS OF 35-55 KTS FOR A BRIEF PERIOD THIS EVENING IN ADVANCE OF THE STORM. WHILE IT WILL PROBABLY BE TOUGH TO MIX THESE DOWN CONSIDERING THE EXPECTED RAINFALL...ELEVATED AREAS...SUCH AS ACROSS THE TACONICS AND MOUNTAINS OF WESTERN NEW ENGLAND HAVE THE POTENTIAL TO SEE SOME GUSTY WINDS. THIS IS ESPECIALLY TRUE BETWEEN THE SRN GREENS AND NORTHERN BERKSHIRES...WHERE E-SE FLOW HAS BEEN KNOWN TO CHANNEL EASILY AND PRODUCE STRONG WINDS. AT THIS POINT...THERE STILL IS TOO MUCH UNCERTAINTY REGARDING THE EXTENT/COVERAGE OF ANY STRONG WINDS TO ISSUE A WIND ADVISORY OR HIGH WIND WARNING...BUT WE WILL MENTION IT IN OUR HWO STATEMENT...AND HAVE COVERED FOR WIND GUSTS OF 35-40 MPH IN OUR CURRENT FORECAST. TOWARDS DAYBREAK...THE STORM/S OCCLUDED FRONT WILL BE NEARING OUR REGION FROM THE WEST. WE PROBABLY WON/T MAKE IT INTO THE STORM/S WARM SECTOR AS THE TRIPLE POINT WILL REMAIN TO OUR SOUTH. STILL...SHOWALTER VALUES WILL BE CLOSE TO ZERO...SO AN ISOLATED RUMBLE OF THUNDER DUE TO SOME ELEVATED CONVECTION CANNOT TOTALLY BE RULED OUT. MIN TEMPS TONIGHT WILL LIKELY BE DURING THE LATE EVENING...AS TEMPS WET BULB DUE TO THE RAINFALL...AND THEN HOLD STEADY OR EVEN RISE SLIGHTLY FOR THE LATE NIGHT HOURS. MOST AREAS WILL FALL INTO THE UPPER 30S TO MID 40S. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE STORM/S OCCLUDED FRONT WILL BE MOVING THROUGH EARLY IN THE DAY WITH A BAND OF RAIN SHOWERS. AFTER THAT...WINDS WILL SWITCH TO A W-SW DIRECTION DURING THE MORNING HOURS...AS THE SFC LOW PASSES NORTH OF THE REGION ACROSS THE ST. LAWRENCE VALLEY. DESPITE BEING BEHIND THE STORM...COOLER AIR MOVING IN ALOFT WILL ALLOW FOR GOOD MIXING...WHICH WILL ALLOW FOR TEMPS TO BE MILD ON TUESDAY. TEMPS WILL RANGE FROM THE UPPER 40S IN THE ADIRONDACKS AND CATSKILLS TO THE MID 50S TO MID 60S FOR VALLEY AREAS. WITH THE UPPER LEVEL SHORTWAVE STILL MOVING ACROSS THE REGION...THERE WILL CONTINUE TO BE A GOOD AMOUNT OF CLOUDS AROUND...ESP FOR CENTRAL/NORTHERN PARTS OF THE AREA. SOME BREAKS OF SUN LOOK POSSIBLE BY LATE IN THE DAY. THERE MAY EVEN BE A FEW LINGERING RAIN SHOWERS...MAINLY FOR THE MOHAWK VALLEY/ADIRONDACKS AND SOUTHERN VERMONT...ALTHOUGH THESE SHOULD BE RATHER LIGHT. THE GOOD MIXING /TO ABOUT 800-850 HPA BASED ON THE LATEST 12Z GFS/NAM BUFKIT SOUNDINGS/ WILL ALLOW FOR SOME GUSTY WEST TO SOUTHWEST WINDS...ESP FOR THE MOHAWK VALLEY...CAPITAL REGION AND BERKSHIRES. WINDS MAY GUST 25-35 MPH AT TIMES DURING THE AFTN AND EARLY EVENING HOURS. WINDS WILL START TO DIMINISH FOR TUESDAY NIGHT BUT LIKELY STILL BE RATHER BRISK. OTHERWISE...SKIES WILL BE PARTLY TO MOSTLY CLOUDY...WITH THE MOST CLOUDS ACROSS THE ADIRONDACKS AND SRN GREENS. THERE MAY BE SOME RAIN OR SNOW SHOWERS OVER THE HIGH TERRAIN AS ANOTHER FAST MOVING UPPER LEVEL SHORTWAVE MOVES ACROSS SOUTHERN CANADA...BUT VALLEY AREAS SHOULD BE FAIRLY QUIET. MIN TEMPS WILL RANGE FROM THE MID 20S TO THE MID 30S. ASIDE FROM A MORNING SNOW/RAIN SHOWER OVER THE WESTERN ADIRONDACKS...IT LOOKS DRY FOR WEDNESDAY INTO WEDNESDAY NIGHT...AS HIGH PRESSURE BUILDS INTO THE EASTERN PORTION OF THE CONUS FROM THE PLAINS. IT STILL MAY BE A LITTLE BREEZY DURING DAYTIME MIXING ON WEDNESDAY AFTN. BEHIND THE DEPARTING SHORTWAVE...TEMPS ALOFT WILL BE A LITTLE COOLER FOR WEDNESDAY /850 HPA TEMPS AROUND -4 TO -8 DEGREES C/...SO MAX TEMPS WILL ONLY REACH THE UPPER 30S TO MID 50S OVER THE REGION. CLEAR SKIES AND LIGHT WINDS WILL ALLOW FOR COOL TEMPS ON WED NIGHT...WITH 20S EVERYWHERE. && .LONG TERM /THURSDAY THROUGH MONDAY/... DURING MOST OF THIS LONG TERM PERIOD OF THE FORECAST...THE WESTERLIES ARE EXPECTED TO BE QUITE ACTIVE AND REMAIN ALONG OR JUST NORTH OF THE U.S./CANADIAN BORDER. THE RESULT FOR OUR REGION WILL BE A GRADUAL INCREASE IN TEMPERATURES THROUGH THE PERIOD. THURSDAY INTO THURSDAY NIGHT... A RATHER STRONG UPPER LEVEL JET AND SURFACE CYCLONE WILL TRACK JUST NORTH OF THE U.S./CANADIAN BORDER WITH ITS ASSOCIATED COLD FRONT TRAILING ACROSS THE GREAT LAKES REGION AND MIGRATING EASTWARD. DUE TO THE UPPER JET CURVATURE...SEEMS MOST OF THE PRECIP THAT DOES OCCUR WILL BE POST-FRONTAL WHILE THE MAIN SUPPORT BECOMES FURTHER REMOVED. WE WILL KEEP POPS INTO THE CHC-SCT VALUES AND BLEND THE LATEST MOS VALUES FROM THE ECMWF/GFS. FRIDAY... THERE IS A TENDENCY FROM THE GLOBAL MODELS THAT ANOTHER UPPER LEVEL WAVE WILL INTERACT WITH THE SURFACE COLD FRONT ACROSS THE OHIO VALLEY. EITHER A WEAK WAVE DEVELOPS ALONG THE BOUNDARY /AS SUGGESTED BY THE THE GFS/ OR A MORE PROGRESSIVE NATURE AS SUGGESTED BY THE ECMWF/GGEM WHICH WOULD KEEP OUR SOUTHERN ZONES DRY. FOR NOW...WE WILL LEAN TOWARD THE DRIER SCENARIO FOR OUR SOUTHERN ZONES. SEASONABLE TEMPERATURES ARE EXPECTED WITH SLIGHTLY COOLER VALUES ACROSS THE ADIRONDACKS. FRIDAY NIGHT INTO SUNDAY... GLOBAL MODELS CONTINUE TO INCREASE CONFIDENCE THAT A SUBTROPICAL RIDGE WILL STRENGTHEN OFF THE SOUTHEAST CONUS WHILE A TROUGH AMPLIFIES OVER THE CENTER OF THE NATION AS A POTENT WAVES DIVES SOUTHWARD ACROSS THE BRITISH COLUMBIA COAST. THE NET RESULT WOULD BE TO SLOW DOWN THE FORWARD PROGRESS OF SURFACE FEATURES AND ALLOW WARM ADVECTION TO OVERSPREAD MOST OF THE EASTERN CONUS. AS H850 TEMPS CLIMB TOWARD +10C AND STRENGTHEN SOUTHWEST FLOW...AFTERNOON HIGH TEMPERATURES SHOULD EASILY CLIMB WELL INTO THE 60S WITH A GRADUAL INCREASE OF OVERNIGHT LOWS FROM THE 30S FRIDAY NIGHT AND WELL INTO THE 40S FOR MANY LOCATIONS SATURDAY NIGHT. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... RAIN SHOWERS AND LOWERING CIGS WILL CONTINUE THROUGH THE NIGHT. MAIN CHALLENGE WILL BE LLWS AS LATEST HI-RESOLUTION MODELS SUGGEST AT OR ABOVE 2K FEET THOSE WIND MAGNITUDES INCREASE TO BETWEEN 40-50KTS. SO WE WILL EXPAND THE LLWS FORECAST TO ALL TAF LOCATIONS TONIGHT. OTHERWISE...MAINLY MVFR CONDITIONS ARE EXPECTED IN BOTH VISIBILITY AND CIGS. CONDITIONS IMPROVE TOWARD SUNRISE TUESDAY AS DRY SLOT BECOMES WELL ENTRENCHED ACROSS THE REGION. COLD FRONT REMAINS UPSTREAM AS ADDITIONAL SHOWERS ARE EXPECTED BUT THE PROBABILITIES AT THIS TIME SEEM A BIT LOW...HENCE THE PROB30 FOR THE AFTERNOON HOURS. WINDS WILL HAVE SHIFTED TOWARD THE SOUTH TO SOUTHWEST AND AN INCREASE IN SUSTAINED WINDS AT OR JUST ABOVE 10KTS WITH GUSTS NEAR 20KTS ARE EXPECTED...ESPECIALLY IN SHOWERS. OUTLOOK... TUESDAY NIGHT: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. WEDNESDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT.BREEZY NO SIG WX. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. SCATTERED SHRA. FRIDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... STRONG WINDS ARE EXPECTED OVER THE NEXT SEVERAL DAYS... RH VALUES WILL BE BELOW 30 PERCENT ON WEDNESDAY AND THURSDAY... AN AREA OF LOW PRESSURE WILL MOVE ACROSS THE REGION TONIGHT INTO TOMORROW...BRINGING A WIDESPREAD WETTING RAIN TO THE REGION. THE HEAVIEST RAINFALL WILL BE ACROSS THE ADIRONDACKS AND ACROSS FAR SOUTHEASTERN PARTS OF THE AREA. MANY HIGH TERRAIN AREAS CONTINUE TO HAVE A SNOW PACK IN PLACE. ALTHOUGH RH VALUES WILL BE HIGH THIS EVENING INTO TONIGHT...RH VALUES WILL LOWER TO 35 TO 50 PERCENT BEHIND THE STORM FOR TOMORROW. RH VALUES WILL BE AS LOW AS 25 PERCENT DURING THE AFTERNOON HOURS ON WEDNESDAY AND THURSDAY. WINDS WILL BE SIGNIFICANT OVER THE NEXT SEVERAL DAYS. S-SE WINDS WILL BE GUSTY THIS EVENING INTO TONIGHT..ESP ACROSS WESTERN NEW ENGLAND WITH GUSTS OVER 40 MPH POSSIBLE. BEHIND THE STORM SYSTEM...W-NW WINDS WILL BE VERY STRONG DURING DAYTIME MIXING TOMORROW AFTN...WITH GUSTS OVER 25 MPH POSSIBLE...ESP IN AREAS THAT CHANNEL WESTERLY FLOW. WINDS WILL CONTINUE BE GUSTY DURING DAYTIME MIXING ON WEDNESDAY WITH GUSTS AROUND 25 MPH POSSIBLE...INCLUDING DURING THE TIME WHEN RH VALUES ARE EXPECTED TO BE VERY LOW. && .HYDROLOGY... RIVER FLOODING CANNOT BE RULED OUT OVER THE NEXT FEW DAYS... AN AREA OF LOW PRESSURE WILL BRING A STEADY LIGHT TO MODERATE RAINFALL TO THE REGION TONIGHT INTO TOMORROW MORNING. THE HEAVIEST RAINFALL WILL BE ACROSS THE ADIRONDACKS...AND ACROSS FAR SOUTHEASTERN PARTS OF THE AREA. WITHIN THESE AREAS...RAINFALL AMOUNTS OF THREE QUARTERS OF AN INCH TO AN INCH AND A QUARTER LOOK TO OCCUR...WITH LOCALLY HIGHER TOTALS POSSIBLE. ELSEWHERE...BASIN RAINFALL AMOUNTS WILL BE A QUARTER TO THREE QUARTERS OF AN INCH. WITH SNOW CONTINUING TO MELT OUT OF THE HIGHEST TERRAIN...THIS WILL LEAD TO SIGNIFICANT RUNOFF...RESULTING IN SHARP RISES ON RIVERS AND STREAMS. WITH THE STEADY RAINFALL LATER THIS EVENING INTO TONIGHT...PONDING OF WATER ON ROADWAYS IS LIKELY...WITH SOME MINOR FLOODING OF POOR DRAINAGE OR URBAN AREAS POSSIBLE AS WELL. THE NERFC CURRENTLY SHOWS SEVERAL RIVERS COMING CLOSE TO BANKFULL BY LATE TONIGHT AND INTO THE DAY ON TUESDAY. IF MORE RAINFALL THAN ANTICIPATED OCCURS OR IF MORE SNOWMELT HAPPENS...THIS COULD RESULT IN MINOR FLOODING ON SOME RIVERS...SUCH AS THE SACANDAGA RIVER IN THE ADIRONDACKS...AS WELL AS PARTS OF THE HOOSIC...METTAWEE...AND HOUSATONIC RIVERS. IN ADDITION...SOME RESERVOIRS AND LAKE WILL BE FILLING UP...AND MINOR FLOODING IS POSSIBLE BY THE MID WEEK PERIOD AT DELTA RESERVOIR ON THE FAR UPPER MOHAWK RIVER. ALTHOUGH MOST RIVERS AND STREAMS ARE FREE OF ICE...THERE ARE SOME RIVERS AND STREAMS ACROSS THE ADIRONDACKS THAT ARE STILL ICE COVERED. WITH RISING LEVELS DUE TO THE RAINFALL AND SNOW MELT...THIS COULD RESULT IN AN ISOLATED ICE JAM BETWEEN TONIGHT AND TOMORROW. RIVERS SHOULD START TO RECEDE DURING THE MID WEEK PERIOD WITH DRY WEATHER ANTICIPATED FOR WEDNESDAY AND THURSDAY. HOWEVER...AN APPROACHING COLD FRONT WILL RETURN THE THREAT OF LIGHT RAIN SHOWERS TO THE REGION FOR FRIDAY. 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...FRUGIS NEAR TERM...FRUGIS/BGM SHORT TERM...FRUGIS LONG TERM...BGM AVIATION...IAA/BGM FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
934 PM EDT MON APR 7 2014 .SYNOPSIS... LOW PRESSURE IN THE OHIO VALLEY WILL MOVE NORTHEASTWARD INTO EASTERN CANADA ON TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS LOW WILL MOVE THROUGH THE REGION ON TUESDAY. HIGH PRESSURE WILL THEN BUILD SOUTH OF THE AREA FOR MOST OF THE WEEK. A SLOW MOVING COLD FRONT IS EXPECTED TO APPROACH THE REGION ON FRIDAY AND THEN STALL ACROSS THE REGION AS LOW PRESSURE MOVES ACROSS IT ON SATURDAY. HIGH PRESSURE SHOULD RETURN FOR SUNDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... LOOKING AT THE MODELS PREDICTED FIELDS VS OBSERVATIONS THRU 00Z, THE ECMWF QPF WI OUR CWA VERIFIED THE CLOSEST, GFS NOT THAT FAR BEHIND. WOULD PLACE THE CANADIANS IN THE MIDDLE AND NAM LAST. LOOKING FORWARD, ALL THE MODELS HAVE A PRETTY GOOD HANDLE OF THE INSTABILITY POCKET OVER WRN PA NEAR THE TROF, BUT ARE OVERDOING THE PREDICTED CONVECTION OVER THE INTERIOR SOUTHEAST. IF ANYTHING, THAT CONVECTION HAS BEEN SWEPT OFFSHORE. THE MODELS CONGEAL THESE TWO AREAS OVER US OVERNIGHT WHICH MAY BE OVERDONE. THE LATEST RAP CONTINUES THIS IDEA, BUT LIKE THE MORE SUBDUED LOOK OF THE LAST HRRR AND ITS SFC BASED L.I. ARE ABOUT 1 TO 2C TOO UNSTABLE. WE UPDATED THE GRIDS TO HAVE THE MENTION OF SOME PATCHY FOG AND THE DRIZZLE THIS EVENING. OTHERWISE WE NARROWED THE WINDOW OF THUNDER MENTION OVERNIGHT. A WAVE ON THE WARM FRONT HAS NUDGED INTO DELMARVA, BUT THINK AT THIS POINT ITS GOING TO MEET PLENTY OF CHILLY RAIN COOLED AIR RESISTANCE AND DONT EXPECT MUCH MORE NORTHWARD PROGRESSION. TEMPS WERE NUDGED UPWARD WELL SOUTH, THE REST HAVE REMAINED CLOSE TO SCHEDULE, NON-DIURNAL AND JUST HOLDING IN PLACE. A SHARPENING UPPER-LEVEL TROUGH WILL SWING ACROSS THE GREAT LAKES LATER TONIGHT. THIS WILL DRIVE A SURFACE LOW UP ACROSS THE EASTERN GREAT LAKES OVERNIGHT. AS THIS OCCURS, THE FLOW ON THE EAST SIDE OF THE TROUGH WILL STRENGTHEN WHICH WILL HELP TO TRANSPORT DEEP MOISTURE NORTHWARD. THE PW VALUES ARE FORECAST TO RISE TO ABOUT 1.0 AND 1.5 INCHES THROUGH THE NIGHT AHEAD OF THE OCCLUDING FRONTAL BOUNDARY. IT APPEARS THAT THE WARM FRONT DOES NOT LIFT NORTH OF OUR ENTIRE AREA AS AN OCCLUSION TAKES PLACE AND RAIN COOLED AIR MAY HANG ON NORTH AND WEST OF THE FALL LINE ESPECIALLY. THERE IS THE POTENTIAL FOR A WARMER AIRMASS TO ADVECT IN ESPECIALLY FROM ABOUT INTERSTATE 95 ON SOUTH AND EASTWARD PRIOR TO DAYBREAK. THIS IS A FORECAST CHALLENGE, AND WE HELD TEMPERATURES EITHER NEARLY STEADY OR EVEN SHOWED SOME RISE THROUGH THE NIGHT. WE DID NOT GO AS ROBUST AS SOME OF THE GUIDANCE SHOWS WITH RESPECT TO THE WARMING DUE TO LOWER CONFIDENCE. THE LARGE SCALE LIFT SHOULD CONTINUE TO STRENGTHEN THROUGH THIS EVENING, PRODUCING PERIODS OF RAIN AS THE WAA AND LOW-LEVEL JET PROVIDE PLENTY OF ISENTROPIC LIFT. THE RAIN COULD BECOME HEAVY AT TIMES FOR SOME AREAS TONIGHT, HOWEVER THE OVERALL SYSTEM LOOKS PROGRESSIVE ENOUGH. DESPITE THE HIGH PW VALUES ANY FLOODING SHOULD BE MINOR AND LOCALIZED. THEREFORE. NO FLOOD WATCH ATTM. WE SHOULD TRANSITION TO MORE OF A SHOWERY REGIME OVERNIGHT AS THE INITIAL LOW-LEVEL INDUCED OVERRUNNING STARTS TO SHIFT TO OUR NORTHEAST AND SOME INSTABILITY MAY ARRIVE. AS THE UPPER-LEVEL TROUGH NEARS OVERNIGHT ALONG WITH THE OCCLUSION, THE FORECAST SOUNDINGS ARE SHOWING AT LEAST SOME ELEVATED INSTABILITY DEVELOPING AND SPREADING NORTHWARD. THIS MAY BE ENOUGH TO PRODUCE SOME ISOLATED THUNDER, HOWEVER GIVEN THE LOW ENOUGH INSTABILITY WE ARE NOT ANTICIPATING ORGANIZED CONVECTION. THE THUNDER POTENTIAL MAY END UP HAVING THE BEST SHOT WITH THE ACTUAL FRONT OVERNIGHT. DESPITE THE SHEAR, THE LOWER INSTABILITY SHOULD KEEP ANY CONVECTION SUB-SEVERE /SLIGHT RISK OF SEVERE STORMS TO OUR SOUTH/. THE SOUNDINGS OVERALL SUGGEST THAT ANY THUNDER WOULD BE ELEVATED, THEREFORE NO ENHANCED WORDING IS BEING CARRIED. THE SOUTHEASTERLY SURFACE FLOW AHEAD OF THE FRONT MAY STRENGTH SOME OVERNIGHT, HOWEVER IF THIS REMAINS ON THE LOW ENOUGH SIDE THEN THERE COULD BE SOME FOG DEVELOPMENT LATE GIVEN THE INCREASED MOISTURE. LOW TEMPERATURES WERE A NAM/GFS MOS BLEND WITH SOME ADJUSTMENT BASED ON FORECAST TEMPERATURES TO START TONIGHT, THEN A NON-DIURNAL WAS USED THROUGH THE NIGHT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... LOW PRESSURE IS FORECAST TO TRACK TO OUR NORTH DURING THE DAY TUESDAY. THIS WILL DRIVE A FRONTAL BOUNDARY THROUGH OUR AREA IN THE MORNING, WITH THE BULK OF THE LIFT SHIFTING FAIRLY QUICKLY OFFSHORE. THEREFORE, ANY SHOWERS ARE EXPECTED TO BE ENDING BY LATE MORNING. THE ENTIRE UPPER-LEVEL TROUGH HOWEVER HANGS BACK TO THE WEST AS ADDITIONAL ENERGY DIVES THROUGH THE BASE OF THE TROUGH NEAR THE CENTRAL GULF COAST. THIS MAY END UP SLOWING THE EASTWARD MOTION OF THE SURFACE FRONT OFFSHORE AS THE UPPER-LEVEL FLOW BECOMES PARALLEL TO IT, HOWEVER THE LATEST THINKING IS THE SHOWERS CLEAR THE COAST BY LATE MORNING. THE HANGING BACK OF THE UPPER-LEVEL TROUGH WILL ALSO DELAY THE COOLING ALOFT ARRIVING ACROSS OUR AREA. THE COMBINATION OF A TIGHTENED PRESSURE GRADIENT AND A WARMING BOUNDARY LAYER WILL TEAM UP WITH DEEPER MIXING, ALLOWING FOR A BREEZY DAY. SINCE THE UPPER-LEVEL TROUGH IS FORECAST TO BE TO OUR WEST DURING THE DAY AND WITH SOME SHORT WAVES MOVING THROUGH, SOME CLOUDINESS MAY HANG ON FOR MUCH OF THE DAY. THERE IS DECENT DRY AIR ADVECTION, HOWEVER ENOUGH LOW-LEVEL MOISTURE HANGING ON MAY CONTRIBUTE TO ATTAINABLE CONVECTIVE TEMPERATURES TO BE REACHED BY MIDDAY. AS FOR HIGH TEMPERATURES, WE USED A NAM/GFS MOS BLEND OVERALL BUT DID MAKE SOME LOCAL TWEAKS && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... HIGH PRESSURE WILL BUILD TO THE SOUTH BEHIND A CFP AND BE THE DOMINANT WX FEATURE FOR MOST OF THE WEEK. EXPECT DRY WX AND WITH NWLY FLOW WED BECOMING W AND SWLY FLOW AT THE SFC THU AND FRI, TEMPS SHUD BE ABV NRML BY THU AND FRI WITH MANY AREAS FLIRTING WITH 70 DEGREES. BY FRI, A CDFNT WILL APPROACH FROM THE NW. THIS FRONT IS SLOW MOVG AND AT LEAST SOME GUID INDICATES THAT A WAVE COULD FORM ON IT AS WELL INTO SAT. SO THE HIGHEST POPS LOOK TO BE FRI NIGHT INTO ERLY SAT. THE SECOND HALF OF SAT SHOULD MARK A RETURN TO DRY WX AND THEN HIGH PRES MOVES IN FOR SUN. ANOTHER MORE POTENT LOW AND CDFNT WILL DEVELOP ACRS THE PLAINS AND APPROACH ON MON. THE GFS IS MUCH FASTER WITH THIS SYS THAN THE ECMWF, WHICH IS NOT A SURPRISE, BUT FOR NOW, AT THIS TIME SCALE WILL JUST CARRY SOME LOW POPS. TEMPS WILL AVERAGE AOA NRML THRU THE PD. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. TONIGHT...IFR AND LIFR CEILINGS WITH VISIBILITIES MVFR/IFR. THE VISIBILITIES WILL MAINLY DEPEND ON THE INTENSITY OF THE RAIN AND DRIZZLE WHICH IS ANTICIPATED AT TIMES. SOME ISOLATED THUNDER CANNOT BE RULED OUT OVERNIGHT WITH THE APPROACHING COLD FRONT, HOWEVER SINCE THIS IS ANTICIPATED TO NOT BE WIDESPREAD IT WAS NOT INCLUDED IN THE TAFS. A LOW-LEVEL JET OF 40-50 KNOTS AT 2,000 FEET IS FORECAST TO SLIDE ACROSS MUCH OF THE AREA, WITH EVEN ABOUT 60 KNOTS AT AND ABOVE 3,000 FEET. THE PLACEMENT OF THE LOW-LEVEL JET LOOKS TO MAINLY BE EAST OF KABE AND KRDG, THEREFORE LOW-LEVEL WIND SHEAR WAS NOT CARRIED HERE. SOUTHEAST SURFACE WINDS GENERALLY AROUND 10 KNOTS WILL THEN SHIFT TO THE SOUTH AND SOUTHWEST LATE. IT IS POSSIBLE ESPECIALLY FROM NEAR THE KPHL METRO ON SOUTH AND EAST, THE WINDS TURN GUSTY AT THE SURFACE FOR A TIME OVERNIGHT. TUESDAY...SUB-VFR EXPECTED TO IMPROVE FAIRLY QUICKLY TO VFR BY MID MORNING AS ANY SHOWERS QUICKLY SHIFT OFFSHORE WITH A COLD FRONT. THE WINDS WILL SHIFT TO A WESTERLY DIRECTION AND INCREASE TO AROUND 15 KNOTS WITH GUSTS TO ABOUT 25 KNOTS. OUTLOOK... TUE NIGHT THRU WED...GENERALLY VFR. BREEZY NW WIND 15 TO 20 KT POSSIBLE DURING THE AFTERNOON. HIGH CONFIDENCE. THU..VFR. HIGH CONFIDENCE. FRI...VFR CONDITIONS EXPECTED EARLY, BUT MAY DETERIORATE TO MVFR WITH -SHRA DURING THE DAY. A SLOW MOVING COLD FRONT COULD ARRIVE DURING FRI OR FRI NIGHT, BRINGING A WIND SHIFT TO NW. THERE ARE SOME TIMING DIFFS WRT THE CFP. LOW TO MDT CONFIDENCE. && .MARINE... A LOW-LEVEL JET WILL SLIDE ACROSS THE AREA TONIGHT AHEAD OF AN OCCLUDING STORM SYSTEM. THIS STORM SYSTEM WILL TRACK TO OUR NORTHWEST OVERNIGHT AND NORTH ON TUESDAY. A SOUTHEASTERLY FLOW WILL INCREASE THROUGH TONIGHT, HOWEVER GIVEN THE WAA OCCURRING OVER THE COLDER WATERS THE FORECAST SOUNDINGS CONTINUE TO SHOW A VERY PRONOUNCED LOW-LEVEL INVERSION. THE STRONGEST WINDS ARE ANTICIPATED TO REMAIN ABOVE THIS INVERSION, AND THEREFORE THE CHC FOR SOME GALES FORCE GUSTS APPEARS TO BE LOW. AS A RESULT, THE SMALL CRAFT ADVISORY REMAINS IN EFFECT. THE SEAS WILL RESPOND TO THE INCREASING WINDS, HOWEVER WE DID SLOW THE BUILDING OF THEM THROUGH THIS EVENING SOME GIVEN A SLOWER START SO FAR. FOR TUESDAY, A FRONTAL BOUNDARY WILL MOVE THROUGH OUR REGION IN THE MORNING BUT MAY SLOW AS IT JUST SHIFTS TO OUR EAST. THE WINDS WILL THEREFORE SHIFT FROM THE SOUTH TO THE WEST BEHIND THE FRONT. DESPITE ENOUGH WIND ABOVE THE SURFACE, THERE APPEARS TO BE MUCH BETTER MIXING OVER LAND GIVEN A WARMER BOUNDARY. THIS WOULD TEND TO KEEP THE STRONGER GUSTINESS NEARSHORE. THEREFORE, WE DID NOT EXTEND THE SMALL CRAFT ADVISORY BEYOND TONIGHT FOR DELAWARE BAY. THIS CAN BE RE-EXAMINED AGAIN TONIGHT. AS THE FLOW TURNS OFFSHORE, THE SEAS WILL GRADUALLY SUBSIDE. OUTLOOK... TUE NIGHT...WINDS AND SEAS WILL DECREASE. EXPECT TO BE BELOW SCA CRITERIA BY DURG THE EVE HOURS IF NOT BEFORE. WED...NO MARINE HEADLINES ANTICIPATED. THU AND FRI...SEAS AND SOUTHWESTERLY WINDS WILL INCREASE THROUGH THE DAY THU AND COULD BE ABOVE SCA CRITERIA BY THU EVE. SCA CONDITIONS SHOULD CONTINUE THU NIGHT THROUGH FRI. A SLOW MOVING COLD FRONT COULD ARRIVE AS EARLY AS FRI EVE, BRINGING SHIFT TO NW WIND. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TUESDAY NIGHT FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ430-431. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GIGI/GORSE SHORT TERM...GORSE LONG TERM...NIERENBERG AVIATION...GORSE/NIERENBERG/PO MARINE...GORSE/NIERENBERG/PO
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
920 PM EDT MON APR 7 2014 .SYNOPSIS... LOW PRESSURE IN THE OHIO VALLEY WILL MOVE NORTHEASTWARD INTO EASTERN CANADA ON TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS LOW WILL MOVE THROUGH THE REGION ON TUESDAY. HIGH PRESSURE WILL THEN BUILD SOUTH OF THE AREA FOR MOST OF THE WEEK. A SLOW MOVING COLD FRONT IS EXPECTED TO APPROACH THE REGION ON FRIDAY AND THEN STALL ACROSS THE REGION AS LOW PRESSURE MOVES ACROSS IT ON SATURDAY. HIGH PRESSURE SHOULD RETURN FOR SUNDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... LOOKING AT THE MODELS PREDICTED FIELDS VS OBSERVATIONS THRU 00Z, THE ECMWF QPF WI OUR CWA VERIFIED THE CLOSEST, GFS NOT THAT FAR BEHIND. WOULD PLACE THE CANADIANS IN THE MIDDLE AND NAM LAST. LOOKING FORWARD, ALL THE MODELS HAVE A PRETTY GOOD HANDLE OF THE INSTABILITY POCKET OVER WRN PA NEAR THE TROF, BUT ARE OVERDOING THE PREDICTED CONVECTION OVER THE INTERIOR SOUTHEAST. IF ANYTHING, THAT CONVECTION HAS BEEN SWEPT OFFSHORE. THE MODELS CONGEAL THESE TWO AREAS OVER US OVERNIGHT WHICH MAY BE OVERDONE. THE LATEST RAP CONTINUES THIS IDEA, BUT LIKE THE MORE SUBDUED LOOK OF THE LAST HRRR AND ITS SFC BASED L.I. ARE ABOUT 1 TO 2C TOO UNSTABLE. WE UPDATED THE GRIDS TO HAVE THE MENTION OF SOME PATCHY FOG AND THE DRIZZLE THIS EVENING. OTHERWISE WE NARROWED THE WINDOW OF THUNDER MENTION OVERNIGHT. A WAVE ON THE WARM FRONT HAS NUDGED INTO DELMARVA, BUT THINK AT THIS POINT ITS GOING TO MEET PLENTY OF CHILLY RAIN COOLED AIR RESISTANCE AND DONT EXPECT MUCH MORE NORTHWARD PROGRESSION. TEMPS WERE NUDGED UPWARD WELL SOUTH, THE REST HAVE REMAINED CLOSE TO SCHEDULE, NON-DIURNAL AND JUST HOLDING IN PLACE. A SHARPENING UPPER-LEVEL TROUGH WILL SWING ACROSS THE GREAT LAKES LATER TONIGHT. THIS WILL DRIVE A SURFACE LOW UP ACROSS THE EASTERN GREAT LAKES OVERNIGHT. AS THIS OCCURS, THE FLOW ON THE EAST SIDE OF THE TROUGH WILL STRENGTHEN WHICH WILL HELP TO TRANSPORT DEEP MOISTURE NORTHWARD. THE PW VALUES ARE FORECAST TO RISE TO ABOUT 1.0 AND 1.5 INCHES THROUGH THE NIGHT AHEAD OF THE OCCLUDING FRONTAL BOUNDARY. IT APPEARS THAT THE WARM FRONT DOES NOT LIFT NORTH OF OUR ENTIRE AREA AS AN OCCLUSION TAKES PLACE AND RAIN COOLED AIR MAY HANG ON NORTH AND WEST OF THE FALL LINE ESPECIALLY. THERE IS THE POTENTIAL FOR A WARMER AIRMASS TO ADVECT IN ESPECIALLY FROM ABOUT INTERSTATE 95 ON SOUTH AND EASTWARD PRIOR TO DAYBREAK. THIS IS A FORECAST CHALLENGE, AND WE HELD TEMPERATURES EITHER NEARLY STEADY OR EVEN SHOWED SOME RISE THROUGH THE NIGHT. WE DID NOT GO AS ROBUST AS SOME OF THE GUIDANCE SHOWS WITH RESPECT TO THE WARMING DUE TO LOWER CONFIDENCE. THE LARGE SCALE LIFT SHOULD CONTINUE TO STRENGTHEN THROUGH THIS EVENING, PRODUCING PERIODS OF RAIN AS THE WAA AND LOW-LEVEL JET PROVIDE PLENTY OF ISENTROPIC LIFT. THE RAIN COULD BECOME HEAVY AT TIMES FOR SOME AREAS TONIGHT, HOWEVER THE OVERALL SYSTEM LOOKS PROGRESSIVE ENOUGH. DESPITE THE HIGH PW VALUES ANY FLOODING SHOULD BE MINOR AND LOCALIZED. THEREFORE. NO FLOOD WATCH ATTM. WE SHOULD TRANSITION TO MORE OF A SHOWERY REGIME OVERNIGHT AS THE INITIAL LOW-LEVEL INDUCED OVERRUNNING STARTS TO SHIFT TO OUR NORTHEAST AND SOME INSTABILITY MAY ARRIVE. AS THE UPPER-LEVEL TROUGH NEARS OVERNIGHT ALONG WITH THE OCCLUSION, THE FORECAST SOUNDINGS ARE SHOWING AT LEAST SOME ELEVATED INSTABILITY DEVELOPING AND SPREADING NORTHWARD. THIS MAY BE ENOUGH TO PRODUCE SOME ISOLATED THUNDER, HOWEVER GIVEN THE LOW ENOUGH INSTABILITY WE ARE NOT ANTICIPATING ORGANIZED CONVECTION. THE THUNDER POTENTIAL MAY END UP HAVING THE BEST SHOT WITH THE ACTUAL FRONT OVERNIGHT. DESPITE THE SHEAR, THE LOWER INSTABILITY SHOULD KEEP ANY CONVECTION SUB-SEVERE /SLIGHT RISK OF SEVERE STORMS TO OUR SOUTH/. THE SOUNDINGS OVERALL SUGGEST THAT ANY THUNDER WOULD BE ELEVATED, THEREFORE NO ENHANCED WORDING IS BEING CARRIED. THE SOUTHEASTERLY SURFACE FLOW AHEAD OF THE FRONT MAY STRENGTH SOME OVERNIGHT, HOWEVER IF THIS REMAINS ON THE LOW ENOUGH SIDE THEN THERE COULD BE SOME FOG DEVELOPMENT LATE GIVEN THE INCREASED MOISTURE. LOW TEMPERATURES WERE A NAM/GFS MOS BLEND WITH SOME ADJUSTMENT BASED ON FORECAST TEMPERATURES TO START TONIGHT, THEN A NON-DIURNAL WAS USED THROUGH THE NIGHT. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... LOW PRESSURE IS FORECAST TO TRACK TO OUR NORTH DURING THE DAY TUESDAY. THIS WILL DRIVE A FRONTAL BOUNDARY THROUGH OUR AREA IN THE MORNING, WITH THE BULK OF THE LIFT SHIFTING FAIRLY QUICKLY OFFSHORE. THEREFORE, ANY SHOWERS ARE EXPECTED TO BE ENDING BY LATE MORNING. THE ENTIRE UPPER-LEVEL TROUGH HOWEVER HANGS BACK TO THE WEST AS ADDITIONAL ENERGY DIVES THROUGH THE BASE OF THE TROUGH NEAR THE CENTRAL GULF COAST. THIS MAY END UP SLOWING THE EASTWARD MOTION OF THE SURFACE FRONT OFFSHORE AS THE UPPER-LEVEL FLOW BECOMES PARALLEL TO IT, HOWEVER THE LATEST THINKING IS THE SHOWERS CLEAR THE COAST BY LATE MORNING. THE HANGING BACK OF THE UPPER-LEVEL TROUGH WILL ALSO DELAY THE COOLING ALOFT ARRIVING ACROSS OUR AREA. THE COMBINATION OF A TIGHTENED PRESSURE GRADIENT AND A WARMING BOUNDARY LAYER WILL TEAM UP WITH DEEPER MIXING, ALLOWING FOR A BREEZY DAY. SINCE THE UPPER-LEVEL TROUGH IS FORECAST TO BE TO OUR WEST DURING THE DAY AND WITH SOME SHORT WAVES MOVING THROUGH, SOME CLOUDINESS MAY HANG ON FOR MUCH OF THE DAY. THERE IS DECENT DRY AIR ADVECTION, HOWEVER ENOUGH LOW-LEVEL MOISTURE HANGING ON MAY CONTRIBUTE TO ATTAINABLE CONVECTIVE TEMPERATURES TO BE REACHED BY MIDDAY. AS FOR HIGH TEMPERATURES, WE USED A NAM/GFS MOS BLEND OVERALL BUT DID MAKE SOME LOCAL TWEAKS && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... HIGH PRESSURE WILL BUILD TO THE SOUTH BEHIND A CFP AND BE THE DOMINANT WX FEATURE FOR MOST OF THE WEEK. EXPECT DRY WX AND WITH NWLY FLOW WED BECOMING W AND SWLY FLOW AT THE SFC THU AND FRI, TEMPS SHUD BE ABV NRML BY THU AND FRI WITH MANY AREAS FLIRTING WITH 70 DEGREES. BY FRI, A CDFNT WILL APPROACH FROM THE NW. THIS FRONT IS SLOW MOVG AND AT LEAST SOME GUID INDICATES THAT A WAVE COULD FORM ON IT AS WELL INTO SAT. SO THE HIGHEST POPS LOOK TO BE FRI NIGHT INTO ERLY SAT. THE SECOND HALF OF SAT SHOULD MARK A RETURN TO DRY WX AND THEN HIGH PRES MOVES IN FOR SUN. ANOTHER MORE POTENT LOW AND CDFNT WILL DEVELOP ACRS THE PLAINS AND APPROACH ON MON. THE GFS IS MUCH FASTER WITH THIS SYS THAN THE ECMWF, WHICH IS NOT A SURPRISE, BUT FOR NOW, AT THIS TIME SCALE WILL JUST CARRY SOME LOW POPS. TEMPS WILL AVERAGE AOA NRML THRU THE PD. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF THIS AFTERNOON...MVFR CEILINGS CONTINUE TO OVERSPREAD THE AREA FROM THE SOUTH, WITH EVEN SOME IFR CEILINGS DEVELOPING. PERIODS OF MAINLY LIGHT RAIN WILL OCCUR, HOWEVER SOME MODERATE RAIN MAY DEVELOP TOWARD EVENING. EAST TO SOUTHEAST WINDS GENERALLY IN THE 10 TO 15 KNOT RANGE, WITH SOME GUSTINESS AT TIMES. ANY ISOLATED THUNDER THAT DEVELOPS IS EXPECTED TO BE WELL TO OUR SOUTH. TONIGHT...IFR CEILINGS /POSSIBLY LIFR/ WITH VISIBILITIES MVFR/IFR. THE VISIBILITIES WILL MAINLY DEPEND ON THE INTENSITY OF THE RAIN AS SOME MODERATE TO HEAVY RAIN IS ANTICIPATED AT TIMES. SOME ISOLATED THUNDER CANNOT BE RULED ESPECIALLY FROM LATER THIS EVENING ONWARD AND WITH THE COLD FRONT, HOWEVER SINCE THIS IS ANTICIPATED TO NOT BE WIDESPREAD IT WAS NOT INCLUDED IN THE TAFS. A LOW-LEVEL JET OF 40-50 KNOTS AT 2,000 FEET IS FORECAST TO SLIDE ACROSS MUCH OF THE AREA, WITH EVEN ABOUT 60 KNOTS AT AND ABOVE 3,000 FEET. THE PLACEMENT OF THE LOW-LEVEL JET LOOKS TO MAINLY BE EAST OF KABE AND KRDG, THEREFORE LOW-LEVEL WIND SHEAR WAS NOT CARRIED HERE. SOUTHEAST SURFACE WINDS GENERALLY AROUND 10 KNOTS WILL THEN SHIFT TO THE SOUTH AND SOUTHWEST LATE. IT IS POSSIBLE ESPECIALLY FROM NEAR THE KPHL METRO ON SOUTH AND EAST, THE WINDS TURN GUSTY AT THE SURFACE FOR A TIME OVERNIGHT. TUESDAY...SUB-VFR EXPECTED TO IMPROVE FAIRLY QUICKLY TO VFR BY MID MORNING AS ANY SHOWERS QUICKLY SHIFT OFFSHORE WITH A COLD FRONT. THE WINDS WILL SHIFT TO A WESTERLY DIRECTION AND INCREASE TO AROUND 15 KNOTS WITH GUSTS TO ABOUT 25 KNOTS. OUTLOOK... TUE NIGHT THRU WED...GENERALLY VFR. BREEZY NW WIND 15 TO 20 KT POSSIBLE DURING THE AFTERNOON. HIGH CONFIDENCE. THU..VFR. HIGH CONFIDENCE. FRI...VFR CONDITIONS EXPECTED EARLY, BUT MAY DETERIORATE TO MVFR WITH -SHRA DURING THE DAY. A SLOW MOVING COLD FRONT COULD ARRIVE DURING FRI OR FRI NIGHT, BRINGING A WIND SHIFT TO NW. THERE ARE SOME TIMING DIFFS WRT THE CFP. LOW TO MDT CONFIDENCE. && .MARINE... A LOW-LEVEL JET WILL SLIDE ACROSS THE AREA TONIGHT AHEAD OF AN OCCLUDING STORM SYSTEM. THIS STORM SYSTEM WILL TRACK TO OUR NORTHWEST OVERNIGHT AND NORTH ON TUESDAY. A SOUTHEASTERLY FLOW WILL INCREASE THROUGH TONIGHT, HOWEVER GIVEN THE WAA OCCURRING OVER THE COLDER WATERS THE FORECAST SOUNDINGS CONTINUE TO SHOW A VERY PRONOUNCED LOW-LEVEL INVERSION. THE STRONGEST WINDS ARE ANTICIPATED TO REMAIN ABOVE THIS INVERSION, AND THEREFORE THE CHC FOR SOME GALES FORCE GUSTS APPEARS TO BE LOW. AS A RESULT, THE SMALL CRAFT ADVISORY REMAINS IN EFFECT. THE SEAS WILL RESPOND TO THE INCREASING WINDS, HOWEVER WE DID SLOW THE BUILDING OF THEM THROUGH THIS EVENING SOME GIVEN A SLOWER START SO FAR. FOR TUESDAY, A FRONTAL BOUNDARY WILL MOVE THROUGH OUR REGION IN THE MORNING BUT MAY SLOW AS IT JUST SHIFTS TO OUR EAST. THE WINDS WILL THEREFORE SHIFT FROM THE SOUTH TO THE WEST BEHIND THE FRONT. DESPITE ENOUGH WIND ABOVE THE SURFACE, THERE APPEARS TO BE MUCH BETTER MIXING OVER LAND GIVEN A WARMER BOUNDARY. THIS WOULD TEND TO KEEP THE STRONGER GUSTINESS NEARSHORE. THEREFORE, WE DID NOT EXTEND THE SMALL CRAFT ADVISORY BEYOND TONIGHT FOR DELAWARE BAY. THIS CAN BE RE-EXAMINED AGAIN TONIGHT. AS THE FLOW TURNS OFFSHORE, THE SEAS WILL GRADUALLY SUBSIDE. OUTLOOK... TUE NIGHT...WINDS AND SEAS WILL DECREASE. EXPECT TO BE BELOW SCA CRITERIA BY DURG THE EVE HOURS IF NOT BEFORE. WED...NO MARINE HEADLINES ANTICIPATED. THU AND FRI...SEAS AND SOUTHWESTERLY WINDS WILL INCREASE THROUGH THE DAY THU AND COULD BE ABOVE SCA CRITERIA BY THU EVE. SCA CONDITIONS SHOULD CONTINUE THU NIGHT THROUGH FRI. A SLOW MOVING COLD FRONT COULD ARRIVE AS EARLY AS FRI EVE, BRINGING SHIFT TO NW WIND. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TUESDAY NIGHT FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 5 AM EDT TUESDAY FOR ANZ430-431. && $$ SYNOPSIS...NIERENBERG NEAR TERM...GIGI/GORSE SHORT TERM...GORSE LONG TERM...NIERENBERG AVIATION...GORSE/NIERENBERG MARINE...GORSE/NIERENBERG
AREA FORECAST DISCUSSION...UPDATED
NWS MELBOURNE FL
440 AM EDT SUN APR 6 2014 .DISCUSSION... ...ABOVE NORMAL TEMPERATURES INTO MONDAY... ...INCREASED CHANCE FOR SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY AHEAD OF A COLD FRONT... TODAY...A WEAK MID LVL DISTURBANCE AT 500 MBS WILL PASS OFFSHORE THIS MORNING. LOW LVL SOUTHERLY FLOW IS EXPECTED TODAY WITH A STATIONARY FRONTAL BOUNDARY NEAR THE FL-GA BORDER LIFTING SLOWLY NWD LATER THIS AFTERNOON AS A WARM FRONT. CONSIDERABLE UPPER LEVEL CIRRUS IS EXPECTED TO AFFECT NRN SECTIONS TODAY BUT SOME THINNING IN THE AFTERNOON AND AFTERNOON SEA BREEZE CONVERGENCE WITH RECOVERING PRECIPITABLE WATER VALUES TO 1.4 TO 1.5 INCHES SHOULD ALLOW SOME ISOLATED CONVECTION ACROSS VOLUSIA COUNTY BY MID TO LATE AFTERNOON. FURTHER SOUTH...LESS CLOUD COVER AND SOUTHERLY FLOW WILL ALLOW HIGHS TO WARM INTO THE MID 80S COASTAL COUNTIES AND UPPER 80S ACROSS THE INTERIOR. TONIGHT...UPPER LEVEL CLOUDINESS WILL CONTINUE TO AFFECT NRN AREAS OVERNIGHT WITH INCREASING LOW LVL SOUTHERLY WINDS TO 20-25 KNOTS AT 925 MBS LATE TONIGHT ALLOWING S WINDS TO STAY UP IN THE 5-10 MPH RANGE. OVERALL AIRMASS WILL REMAIN DRY IN THE H8-H5 LAYER PREFRONTAL SHOWER ACTIVITY IS NOT EXPECTED. LOWS IN THE MID TO UPPER 60S. MON-TUE...THE SRN BRANCH OF THE H30-H20 JET STREAM HAS EXPANDED ACRS THE NA CONTINENT WITH THE 100KT ISOTACH EXTENDING FROM THE CAPE HATTERAS TO THE BAJA PENINSULA...WITH A 120KT CORE EXTENDING FROM THE LWR MS VALLEY TO THE RIO GRANDE VALLEY. THE RIGHT REAR QUAD OF THIS JET IS POSITIONED OVER A STALLED FRONTAL BNDRY OVER THE NRN GULF COAST AND WILL INDUCE A NEW STORM SYSTEM OUT OF A BROAD AREA OF LOW PRES OVER W TX. THE SRN BRANCH OF THE JET STREAM WILL AMPLIFY IN RESPONSE TO A 100KT NRN STREAM JET DIGGING INTO THE PAC NW...FORCING THE SRN STREAM TO SHIFT OF A LIFTING ORIENTATION BY DAYBREAK MON BEFORE STRENGTHENING TO A 140-150KT CORE BY DAYBREAK TUE. THIS WILL ALLOW THE STORM SYSTEM LIFT RAPIDLY NE WHILE DVLPG INTO A RATHER POTENT 980MB LOW AS IT PASSES OVER NEW ENGLAND EN ROUTE TO THE CANADIAN MARITIMES LATE TUE NIGHT. MODEL GUIDANCE HAS BEEN CONSISTENT OVER THE PAST SEVERAL RUNS WITH THE PASSING OF A COLD FRONT/SQUALL LINE THRU CENTRAL FL MON NIGHT THRU TUE. LATEST RUC ANALYSIS SHOWS THE NRN STREAM JET HAS PLENTY OF UPSTREAM ENERGY LEFT TO FEED INTO THE AMPLIFYING PATTERN...CAN SEE NO REASON TO DEVIATE FROM THE PRESENT FCST REASONING AS RESULTING W/NWRLY FLOW BEHIND THE STORM SYSTEM SHOULD BE ENOUGH TO SHUNT A LATE SEASON COLD FRONT THRU CENTRAL FL BY BY SUNSET TUE. MID/UPR LVL DYNAMIC HAS CONSOLIDATED SOMEWHAT OVER THE PAST 24HRS WITH A GOOD UPR LVL DIVERGENCE COUPLET COINCIDENT WITH MID LVL OMEGA LIFT... WITH A TRAILING MID VORT MAX INDICATING SUSTAINED MID LVL SUPPORT. WX WILL BE DRY TO START AFT SUNRISE MON AS SUBSTANTIAL MID LVL DRY AIR REMAIN IN PLACE. ALSO...MODELS CONTINUE TO INDICATE A DENSE FIELD OF MID/UPR LVL DEBRIS CLOUDS WILL PRECEDE THE FROPA THAT WILL HAMPER SFC HEATING/DESTABILIZATION. EVEN SO...THE DYNAMIC SUPPORT APPEARS SUFFICIENT ENOUGH TO KEEP CHC/SLGT CHC OF AFTN POPS IN THE FCST AFT 18Z MON. PRECIP CHANCES BCMG LIKELY AREAWIDE BTWN 00Z TUE AND 00Z WED WITH INTENSITY OF AND CONVECTION REMAINING THE BIG QUESTION. MODEL SOUNDINGS INCREASE PWAT VALUES AT KMCO TO ARND 1.7" BY 06Z TUE WITH 0-3KM HELICITY INCREASING TO BTWN 300-350 M2/S2...CAPE VALUES CLIMBING OVER 2000 J/KG...ARND 1500...ACCOMPANIED BY 45KT-50KT SW WINDS THRU THE H95-H70 LYR BY DAYBREAK TUE. GFS/ECMWF TIMING FOR THE SQUALL LINE IT PRETTY CLOSE...PUSHING IT THRU CENTRAL FL BTWN 12Z TUE AND 00Z WED. A DISTINCT POTENTIAL FOR STRONG TO SVR WX REMAINS IN PLAY. HODOGRAPHS INDICATE PRIMARY THREAT WILL BE STRAIGHT LINE WINDS...THOUGH THE INCREASING HELICITY SUGGESTS ROTATING STORMS CANNOT BE RULED OUT. H50 TEMPS ARND -8C INDICATES LARGE HAIL THREAT WILL BE MARGINAL AT BEST. THE PERSISTENT S/SWRLY FLOW WILL PUSH MON AFTN TEMPS INTO THE M80S ALONG THE COAST AND U80S/L90S INTERIOR WHILE HOLDING OVERNIGHT MIN TEMPS IN THE U60S/L70S INTERIOR...L/M70S ALONG THE COAST. AS THE FRONT PUSHES THRU...RAIN COOLED AIR AND WEAK COOL AIR ADVECTION WILL ALLOW TUE MAX/MIN TEMPS TO DROP BACK INTO THE U70S/L80S ALONG AND N OF I-4...L/M80S TO THE S. POST FRONTAL COOL AIR ADVECTION TUE NIGHT WILL DROP TEMPS INTO THE L/M50S ALONG AND N OF I-4...U50S/L60S ALONG THE TREASURE COAST. WED-SAT... SEASONABLE WX CONDITIONS THRU THE LATTER HALF OF THE WEEK AS A STRONG POST FRONTAL HI PRES RIDGE BUILDS ACRS THE GOMEX AND INTO THE W ATLC. POST FRONTAL COOL DOWN WILL BE LIMITED TO WED WITH MAX TEMPS DIPPING INTO THE L/M70S N OF I-4...HOLDING IN THE M/U70S TO THE S... MIN TEMPS HOLDING IN THE L/M50S OVER MOST OF THE CWA EXCEPT U50S ALONG THE IMMEDIATE TREASURE COAST. THE COOL AIRMASS WILL MODIFY THRU LATE WEEK AS THE RIDGE PUSHES OFFSHORE AND ALLOWS AN ONSHORE FLOW TO DVLP. MAX/MIN TEMPS ON THU WILL RECOVER TO WITHIN 5F OF CLIMO AVG (U70S/L80S AND U50S/L60S RESPECTIVELY) AND HOLD STEADY THRU THE END OF THE WEEK. EXTENDED MOS GUIDANCE SUGGESTS ISOLD COASTAL SHRAS BY THE END OF THE WEEK IN THE DEEPENING ERLY FLOW...BUT THESE WOULD HAVE MINIMAL IMPACT AND WILL NOT BE INCLUDED IN THE FCST. && .AVIATION...MAINLY VFR THROUGH 07/06Z. A SMALL AFTERNOON SHOWER CHC AT KDAB AND HAVE INCLUDED VCSH AFT 19Z. UPPER LVL CIRRUS WILL AFFECT NRN TERMINALS INTO TONIGHT. && .MARINE...S WINDS AROUND 10 KNOTS TODAY WILL BECOME SSE/SE THIS AFTERNOON AND INCREASE TO 10-15 KNOTS. SEAS 2-3 FT NEAR SHORE AND 3-4 FT WELL OFFSHORE. S WINDS WILL INCREASE TO AROUND 15 KNOTS TONIGHT WITH SEAS BUILDING TO 4-5 FT LATE ACROSS THE OFFSHORE WATERS. MON-MON NIGHT...STORM SYSTEM LIFTING FROM THE MS/TN RIVER VALLEYS INTO THE GREAT LAKES REGION WILL RIDE UP THE BACK SIDE OF THE THE ATLC HIGH PRES RIDGE...SUPPRESSING IT INTO THE FL STRAITS. INTERACTION BTWN THESE TWO SYSTEMS WILL GENERATE A MODERATE TO FRESH SRLY BREEZE THRU THE DAY...BCMG FRESH TO STRONG AFT MIDNIGHT MON INTO TUE AS A SQUALL LINE PRESSES INTO THE I-4 CORRIDOR. SEAS BUILDING TO 3-5FT NEARSHORE AND 5-7FT OFFSHORE. TUE-TUE NIGHT...FRESH TO STRONG SWRLY BREEZE WILL PREVAIL AS THE SQUALL LINE PRESSES THRU CENTRAL FL. WINDS MAY BRIEFLY DIMINISH BEHIND THE SQUALL LINE BUT ARE EXPECTED TO PICKUP OUT OF THE W/NW AFT SUNSET AS A POST FRONTAL WIND SURGE BOOSTS SUSTAINED SPEEDS INTO THE 20-25KT RANGE. THE OFFSHORE WIND COMPONENT WILL LEAVE THE LCL ATLC FETCH PROTECTED...LIMITING SEAS TO 3-5FT NEARSHORE AND 5-7FT OFFSHORE. EVEN SO...THESE WILL CONSIST OF ROUGH SHORT PD WIND WAVES THAT WILL MAKE LOCAL BOATING CONDITIONS QUITE HAZARDOUS. WED-NIGHT...CONDITIONS WILL GRADUALLY IMPROVE THRU THE DAY AS A LARGE HIGH PRES RIDGE BUILDS INTO GOMEX/DEEP SOUTH. EVEN SO... OVERALL BOATING CONDITIONS WILL REMAIN HAZARDOUS THRU LATE AFTN AS WINDS SPIN DOWN...DIMINISHING TO 10-15KTS BY SUNSET WHILE VEERING THRU DUE N. THE OPPOSING WIND/GULFSTREAM DIRECTIONS WILL MAINTAIN ROUGH SEAS OVER MUCH OF THE AREA. SEAS 3-5FT NEARSHORE AND 5-7FT OFFSHORE TO START THE DAY...SUBSIDING TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE OVERNIGHT. THU-THU NIGHT...HI PRES WILL BUILD INTO THE W ATLC AND GENERATE A GENTLE TO MODERATE NE BREEZE THRU THE DAY...VEERING TO DUE E BY SUNSET AND CONTG OVERNIGHT. SEAS 2-3FT NEARSHORE AND 3-4FT OFFSHORE. && .FIRE WEATHER...MIN RHS AROUND 40 PCT ACROSS THE INTERIOR WITH SOUTHERLY WINDS AND A SE WIND DEVELOPING ALONG THE COAST WITH THE AFTERNOON SEA BREEZE BY EARLY TO MID AFTERNOON TODAY. DRIER AIR AND CRITICAL MIN RH LEVELS EXPECTED BEHIND THE NEXT FRONT ON WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... DAB 83 66 84 69 / 20 10 40 60 MCO 87 66 88 69 / 10 10 40 60 MLB 84 68 84 72 / 10 10 20 50 VRB 84 67 84 73 / 10 10 20 40 LEE 85 67 87 69 / 10 10 40 60 SFB 87 67 87 70 / 10 10 40 60 ORL 87 68 87 71 / 10 10 40 60 FPR 83 68 84 74 / 10 10 20 30 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM/AVIATION...VOLKMER LONG TERM....BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
420 AM EDT SUN APR 6 2014 .DISCUSSION... ...ABOVE NORMAL TEMPERATURES INTO MONDAY... ...INCREASED CHANCE FOR SHOWERS AND THUNDERSTORMS MONDAY NIGHT INTO TUESDAY AHEAD OF A COLD FRONT... TODAY...A WEAK MID LVL DISTURBANCE AT 500 MBS WILL PASS OFFSHORE THIS MORNING. LOW LVL SOUTHERLY FLOW IS EXPECTED TODAY WITH A STATIONARY FRONTAL BOUNDARY NEAR THE FL-GA BORDER LIFTING SLOWLY NWD LATER THIS AFTERNOON AS A WARM FRONT. CONSIDERABLE UPPER LEVEL CIRRUS IS EXPECTED TO AFFECT NRN SECTIONS TODAY BUT SOME THINNING IN THE AFTERNOON AND AFTERNOON SEA BREEZE CONVERGENCE WITH RECOVERING PRECIPITABLE WATER VALUES TO 1.4 TO 1.5 INCHES SHOULD ALLOW SOME ISOLATED CONVECTION ACROSS VOLUSIA COUNTY BY MID TO LATE AFTERNOON. FURTHER SOUTH...LESS CLOUD COVER AND SOUTHERLY FLOW WILL ALLOW HIGHS TO WARM INTO THE MID 80S COASTAL COUNTIES AND UPPER 80S ACROSS THE INTERIOR. TONIGHT...UPPER LEVEL CLOUDINESS WILL CONTINUE TO AFFECT NRN AREAS OVERNIGHT WITH INCREASING LOW LVL SOUTHERLY WINDS TO 20-25 KNOTS AT 925 MBS LATE TONIGHT ALLOWING S WINDS TO STAY UP IN THE 5-10 MPH RANGE. OVERALL AIRMASS WILL REMAIN DRY IN THE H8-H5 LAYER PREFRONTAL SHOWER ACTIVITY IS NOT EXPECTED. LOWS IN THE MID TO UPPER 60S. MON-TUE...THE SRN BRANCH OF THE H30-H20 JET STREAM HAS EXPANDED ACRS THE NA CONTINENT WITH THE 100KT ISOTACH EXTENDING FROM THE CAPE HATTERAS TO THE BAJA PENINSULA...WITH A 120KT CORE EXTENDING FROM THE LWR MS VALLEY TO THE RIO GRANDE VALLEY. THE RIGHT REAR QUAD OF THIS JET IS POSITIONED OVER A STALLED FRONTAL BNDRY OVER THE NRN GULF COAST AND WILL INDUCE A NEW STORM SYSTEM OUT OF A BROAD AREA OF LOW PRES OVER W TX. THE SRN BRANCH OF THE JET STREAM WILL AMPLIFY IN RESPONSE TO A 100KT NRN STREAM JET DIGGING INTO THE PAC NW...FORCING THE SRN STREAM TO SHIFT OF A LIFTING ORIENTATION BY DAYBREAK MON BEFORE STRENGTHENING TO A 140-150KT CORE BY DAYBREAK TUE. THIS WILL ALLOW THE STORM SYSTEM LIFT RAPIDLY NE WHILE DVLPG INTO A RATHER POTENT 980MB LOW AS IT PASSES OVER NEW ENGLAND EN ROUTE TO THE CANADIAN MARITIMES LATE TUE NIGHT. MODEL GUIDANCE HAS BEEN CONSISTENT OVER THE PAST SEVERAL RUNS WITH THE PASSING OF A COLD FRONT/SQUALL LINE THRU CENTRAL FL MON NIGHT THRU TUE. LATEST RUC ANALYSIS SHOWS THE NRN STREAM JET HAS PLENTY OF UPSTREAM ENERGY LEFT TO FEED INTO THE AMPLIFYING PATTERN...CAN SEE NO REASON TO DEVIATE FROM THE PRESENT FCST REASONING AS RESULTING W/NWRLY FLOW BEHIND THE STORM SYSTEM SHOULD BE ENOUGH TO SHUNT A LATE SEASON COLD FRONT THRU CENTRAL FL BY BY SUNSET TUE. MID/UPR LVL DYNAMIC HAS CONSOLIDATED SOMEWHAT OVER THE PAST 24HRS WITH A GOOD UPR LVL DIVERGENCE COUPLET COINCIDENT WITH MID LVL OMEGA LIFT... WITH A TRAILING MID VORT MAX INDICATING SUSTAINED MID LVL SUPPORT. WX WILL BE DRY TO START AFT SUNRISE MON AS SUBSTANTIAL MID LVL DRY AIR REMAIN IN PLACE. ALSO...MODELS CONTINUE TO INDICATE A DENSE FIELD OF MID/UPR LVL DEBRIS CLOUDS WILL PRECEDE THE FROPA THAT WILL HAMPER SFC HEATING/DESTABILIZATION. EVEN SO...THE DYNAMIC SUPPORT APPEARS SUFFICIENT ENOUGH TO KEEP CHC/SLGT CHC OF AFTN POPS IN THE FCST AFT 18Z MON. PRECIP CHANCES BCMG LIKELY AREAWIDE BTWN 00Z TUE AND 00Z WED WITH INTENSITY OF AND CONVECTION REMAINING THE BIG QUESTION. MODEL SOUNDINGS INCREASE PWAT VALUES AT KMCO TO ARND 1.7" BY 06Z TUE WITH 0-3KM HELICITY INCREASING TO BTWN 300-350 M2/S2...CAPE VALUES CLIMBING OVER 2000 J/KG...ARND 1500...ACCOMPANIED BY 45KT-50KT SW WINDS THRU THE H95-H70 LYR BY DAYBREAK TUE. GFS/ECMWF TIMING FOR THE SQUALL LINE IT PRETTY CLOSE...PUSHING IT THRU CENTRAL FL BTWN 12Z TUE AND 00Z WED. A DISTINCT POTENTIAL FOR STRONG TO SVR WX REMAINS IN PLAY. HODOGRAPHS INDICATE PRIMARY THREAT WILL BE STRAIGHT LINE WINDS...THOUGH THE INCREASING HELICITY SUGGESTS ROTATING STORMS CANNOT BE RULED OUT. H50 TEMPS ARND -8C INDICATES LARGE HAIL THREAT WILL BE MARGINAL AT BEST. THE PERSISTENT S/SWRLY FLOW WILL PUSH MON AFTN TEMPS INTO THE M80S ALONG THE COAST AND U80S/L90S INTERIOR WHILE HOLDING OVERNIGHT MIN TEMPS IN THE U60S/L70S INTERIOR...L/M70S ALONG THE COAST. AS THE FRONT PUSHES THRU...RAIN COOLED AIR AND WEAK COOL AIR ADVECTION WILL ALLOW TUE MAX/MIN TEMPS TO DROP BACK INTO THE U70S/L80S ALONG AND N OF I-4...L/M80S TO THE S. POST FRONTAL COOL AIR ADVECTION TUE NIGHT WILL DROP TEMPS INTO THE L/M50S ALONG AND N OF I-4...U50S/L60S ALONG THE TREASURE COAST. WED-SAT... UPDATE TO FOLLOW. && .AVIATION...MAINLY VFR THROUGH 07/06Z. A SMALL AFTERNOON SHOWER CHC AT KDAB AND HAVE INCLUDED VCSH AFT 19Z. UPPER LVL CIRRUS WILL AFFECT NRN TERMINALS INTO TONIGHT. && .MARINE...S WINDS AROUND 10 KNOTS TODAY WILL BECOME SSE/SE THIS AFTERNOON AND INCREASE TO 10-15 KNOTS. SEAS 2-3 FT NEAR SHORE AND 3-4 FT WELL OFFSHORE. S WINDS WILL INCREASE TO AROUND 15 KNOTS TONIGHT WITH SEAS BUILDING TO 4-5 FT LATE ACROSS THE OFFSHORE WATERS. MON-MON NIGHT...STORM SYSTEM LIFTING FROM THE MS/TN RIVER VALLEYS INTO THE GREAT LAKES REGION WILL RIDE UP THE BACK SIDE OF THE THE ATLC HIGH PRES RIDGE...SUPPRESSING IT INTO THE FL STRAITS. INTERACTION BTWN THESE TWO SYSTEMS WILL GENERATE A MODERATE TO FRESH SRLY BREEZE THRU THE DAY...BCMG FRESH TO STRONG AFT MIDNIGHT MON INTO TUE AS A SQUALL LINE PRESSES INTO THE I-4 CORRIDOR. SEAS BUILDING TO 3-5FT NEARSHORE AND 5-7FT OFFSHORE. TUE-TUE NIGHT...FRESH TO STRONG SWRLY BREEZE WILL PREVAIL AS THE SQUALL LINE PRESSES THRU CENTRAL FL. WINDS MAY BRIEFLY DIMINISH BEHIND THE SQUALL LINE BUT ARE EXPECTED TO PICKUP OUT OF THE W/NW AFT SUNSET AS A POST FRONTAL WIND SURGE BOOSTS SUSTAINED SPEEDS INTO THE 20-25KT RANGE. THE OFFSHORE WIND COMPONENT WILL LEAVE THE LCL ATLC FETCH PROTECTED...LIMITING SEAS TO 3-5FT NEARSHORE AND 5-7FT OFFSHORE. EVEN SO...THESE WILL CONSIST OF ROUGH SHORT PD WIND WAVES THAT WILL MAKE LOCAL BOATING CONDITIONS QUITE HAZARDOUS. WED-NIGHT...CONDITIONS WILL GRADUALLY IMPROVE THRU THE DAY AS A LARGE HIGH PRES RIDGE BUILDS INTO GOMEX/DEEP SOUTH. EVEN SO... OVERALL BOATING CONDITIONS WILL REMAIN HAZARDOUS THRU LATE AFTN AS WINDS SPIN DOWN...DIMINISHING TO 10-15KTS BY SUNSET WHILE VEERING THRU DUE N. THE OPPOSING WIND/GULFSTREAM DIRECTIONS WILL MAINTAIN ROUGH SEAS OVER MUCH OF THE AREA. SEAS 3-5FT NEARSHORE AND 5-7FT OFFSHORE TO START THE DAY...SUBSIDING TO 2-4FT NEARSHORE AND 3-5FT OFFSHORE OVERNIGHT. THU-THU NIGHT...HI PRES WILL BUILD INTO THE W ATLC AND GENERATE A GENTLE TO MODERATE NE BREEZE THRU THE DAY...VEERING TO DUE E BY SUNSET AND CONTG OVERNIGHT. SEAS 2-3FT NEARSHORE AND 3-4FT OFFSHORE. && .FIRE WEATHER...MIN RHS AROUND 40 PCT ACROSS THE INTERIOR WITH SOUTHERLY WINDS AND A SE WIND DEVELOPING ALONG THE COAST WITH THE AFTERNOON SEA BREEZE BY EARLY TO MID AFTERNOON TODAY. DRIER AIR AND CRITICAL MIN RH LEVELS EXPECTED BEHIND THE NEXT FRONT ON WEDNESDAY. && .PRELIMINARY POINT TEMPS/POPS... DAB 83 66 84 69 / 20 10 40 60 MCO 87 66 88 69 / 10 10 40 60 MLB 84 68 84 72 / 10 10 20 50 VRB 84 67 84 73 / 10 10 20 40 LEE 85 67 87 69 / 10 10 40 60 SFB 87 67 87 70 / 10 10 40 60 ORL 87 68 87 71 / 10 10 40 60 FPR 83 68 84 74 / 10 10 20 30 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM/AVIATION...VOLKMER LONG TERM....BRAGAW
AREA FORECAST DISCUSSION...UPDATED
NWS COLUMBIA SC
1034 PM EDT MON APR 7 2014 .SYNOPSIS... A COLD FRONT APPROACHING FROM THE WEST WILL MOVE THROUGH THE FORECAST AREA LATE TONIGHT. A LINGERING TROUGH IN THE FORECAST AREA WILL MOVE OUT OF THE AREA WEDNESDAY WITH HIGH PRESSURE DOMINATING DURING THE REST OF THE WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... SCATTERED SHOWERS CONTINUE TO DEVELOP IN THE REGION BETWEEN THE DEPARTING STRONG CONVECTION OFF THE COAST AND THE COLD FRONT TO THE WEST. SLIGHTLY DIFFLUENT FLOW AT 500MB AND MODERATE SOUTHWESTERLY LOW LEVEL FLOW CONTINUE TO PROVIDE LIFT AND MOISTURE FOR ADDITIONAL SHOWERS. THE COLD FRONT WILL PUSH THROUGH THE FORECAST AREA DURING THE 09Z-12Z TIME FRAME AND PRECIPITATION WILL END FROM WEST TO EAST AS THE FRONT PASSES. TEMPERATURES CONTINUE TO WARM AHEAD OF THE FRONT AS THE WEDGE ERODES AND SOUTHERLY FLOW PERSISTS. OVERNIGHT LOWS WILL BE HIGHLY DEPENDENT ON HOW FAR EAST THE FRONT GETS BY 12Z AND HAVE LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60 EAST. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE COLD FRONT WILL BE EAST OF THE FORECAST AREA BY SUNRISE TUESDAY. HOWEVER...THE DEEP UPPER-LEVEL TROUGH IS NOT FORECAST TO SWING THROUGH THE AREA UNTIL TUESDAY NIGHT AND WEDNESDAY. THE COLD AIR ALOFT ASSOCIATED WITH THE TROUGH AND ITS WEAK SURFACE REFLECTION MAY HELP CAUSE SCATTERED SHOWERS TUESDAY INTO WEDNESDAY. AN AVERAGE OF THE GFS AND NAM MOS SUPPORT POPS AROUND 20 PERCENT. WE USED THE COOLER HIGH TEMPERATURE GUIDANCE BECAUSE OF THE SHARP UPPER-LEVEL TROUGH TUESDAY. STRONG NET RADIATIONAL COOLING SUPPORTED THE COLDER TEMPERATURE GUIDANCE WEDNESDAY NIGHT. && .LONG TERM /THURSDAY THROUGH MONDAY/... THE GFS AND ECMWF INDICATE A DRY PATTERN WITH HIGH PRESSURE DOMINATING THROUGH THE WEEKEND. THE MODELS SHOW ANOTHER COLD FRONT AND ASSOCIATED MOISTURE AFFECTING THE AREA MONDAY. THE GFS AND ECMWF MOS SUPPORT NEAR- NORMAL TEMPERATURES THURSDAY AND FRIDAY...WITH ABOVE NORMAL READINGS SATURDAY AND SUNDAY. THE GFS AND ECMWF MOS SUPPORT POPS OF 30 TO 40 PERCENT MONDAY. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... BULK OF SHOWERS ARE SLOWLY MOVING EAST AND EXITING THE FORECAST AREA LATE THIS EVENING. SOME VFR CONDITIONS LATE IN THE EVENING...BUT IFR TO MVFR CIGS ARE EXPECTED TO RETURN FOR MUCH OF THE OVERNIGHT HOURS. LAMP GUIDANCE AND HRRR LEANING TOWARDS IFR/POSSIBLE LIFR CIGS OVERNIGHT. HAVE LEANED TOWARDS IFR CIGS THROUGH 12Z TUESDAY AT ALL TAF SITES. FRONTAL BOUNDARY EXPECTED TO MOVE THROUGH AROUND 09Z TO 12Z. RADAR TRENDS INDICATING A FEW SHOWERS AHEAD OF THE COLD FRONT. WILL HANDLE WITH A -SHRA OR A VCSH UNTIL THE PRE-DAWN HOURS. EXPECT IMPROVING CONDITIONS AND A WIND SHIFT TO THE WEST TOWARDS DAYBREAK...THOUGH MVFR CIG RESTRICTIONS MAY CONTINUE UNTIL LATE TUESDAY MORNING. CIGS SHOULD BECOME VFR AT ALL TAF SITES BY TUESDAY AFTERNOON. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
729 AM EDT SUN APR 6 2014 .SYNOPSIS... A WEAK BACKDOOR COLD FRONT WILL STALL SOUTH OF THE AREA TODAY THEN LIFT NORTH AS A WARM FRONT LATER TONIGHT AND MONDAY MORNING. A STRONGER COLD FRONT WILL MOVE THROUGH THE REGION MONDAY NIGHT FOLLOWED BY AN UPPER LEVEL DISTURBANCE TUESDAY NIGHT. COOLER AND DRIER HIGH PRESSURE WILL THEN PREVAIL THROUGH THURSDAY BEFORE MILDER WEATHER RETURNS AS THE HIGH MOVES OFFSHORE. && .NEAR TERM /THROUGH TONIGHT/... NEAR DAYBREAK...UPDATED TO LOWER SOME OF MORNING RAIN CHANCES NORTH OF A LINE FROM HAMPTON TO CHARLESTON. LATEST NAM/HRRR SUGGESTS RAINS COULD HOLD OFF UNTIL LATER THIS MORNING AS THE DEEP LAYERED AIR MASS IS DRIER AND LOW LEVEL DEW POINTS HAVE FALLEN WELL BELOW FORECASTED VALUES AT 11Z. TODAY...QUITE A COMPLEX FORECAST SCENARIO BUT THE OVERALL PICTURE REMAINS UNCHANGED AS DEEP MOISTURE ADVECTS E AND ENE FROM THE NORTHERN GULF COAST ACROSS SE GEORGIA AND EXTREME SOUTHERN SOUTH CAROLINA TODAY. PWATS IN EXCESS OF 1.5 INCHES WILL ACCOMPANY AN ENERGETIC MID LEVEL SHORT WAVE WHICH HAS BEEN PRODUCING COPIOUS ELEVATED CONVECTIVE RAINS OVERNIGHT ACROSS THE LOWER GULF COAST REGION. INCREASING ISENTROPIC ASCENT AND UPPER FORCING/DIFLUENCE PROGGED TO FOCUS A REGION OF MODERATE RAINS WITH LOCALLY HEAVY ELEVATED CONVECTIVE RAINS ALONG AND SOUTH OF I-16 LATER THIS MORNING INTO AT LEAST MID AFTERNOON. MANY OF THE 00Z MODELS SPIT OUT OVER AN INCH OF RAIN FROM METTER TO STATESBORO AND SAVANNAH/BEAUFORT WITH THE 00Z ECMWF THE OUTLIER MODEL WITH THE LOWEST QPF TALLIES ACROSS OUR REGION...AROUND 1/2 INCH IN GEORGIA. CATEGORICAL POPS MOST AREAS TODAY WITH SOME DRIER AIR HANGING TOUGH ACROSS THE NORTHERN HALF OF THE CHARLESTON TRI-COUNTY AREA MAYBE KEEPING RAIN COVERAGE/AMOUNTS LOWER FROM ABOUT ST. GEORGE TO JAMESTOWN. MODELS DO NOT SHOW MUCH ELEVATED INSTABILITY BUT GIVEN ONGOING UPSTREAM TRENDS AND RAP ANALYSIS...WE FELT THAT A SLIGHT CHANCE OF ELEVATED TSTMS WAS WORTH A MENTION S OF I-16. WITH THE WEDGE PATTERN DIGGING IN AND PLENTY OF RAINFALL...TEMPS WILL LIKELY BE LOWER MUCH OF THE DAY THAN CURRENT READINGS WE ARE SEEING OVERNIGHT WHICH MAKES FOR PROBLEMATIC TEMP FORECASTING AS ATYPICAL DIURNAL CURVES AND STEADY READINGS LIKELY THE STORY FOR THE LATE MORNING AND AFTERNOON HOURS. THE BULK OF THE UPPER FORCING WILL SHIFT OFF THE COAST LATE TODAY AND TONIGHT WITH LOWER CHANCES FOR SOME SHOWERS WITH THE WARM FRONT AND PERHAPS SOME DRIZZLY WEATHER AT TIMES. LOW STRATUS WILL LIKELY EXPAND UNDER THE WEDGE INVERSION WITH LOW TEMPS IN THE MID 50S NORTH TO LOWER 60S ALONG THE SE GEORGIA COAST. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... MONDAY...A WARM FRONT WILL SHIFT NORTH THROUGH THE AREA MONDAY MORNING PLACING THE FORECAST AREA IN THE WARM SECTOR OF THE STRENGTHENING STORM SYSTEM MOVING NORTHEAST INTO THE OHIO VALLEY. ABUNDANT MOISTURE WILL BE MOVING INTO THE AREA AHEAD OF THE TRAILING COLD FRONT. MOSTLY EXPECT SOME MORNING SHOWERS NEAR THE WARM FRONT ACROSS SOUTHERN SOUTH CAROLINA WITH RAIN CHANCES INCREASING FROM THE WEST DURING THE AFTERNOON. THERE SHOULD BE A GOOD BIT OF HIGH CLOUDS WHICH WILL LIMIT HEATING SOMEWHAT AND THIS WILL LIKELY PLAY INTO THE AMOUNT OF INSTABILITY AND VERTICAL MIXING THAT WILL OCCUR. WE REMAIN IN A SLIGHT RISK AREA FOR SEVERE STORMS SO WILL NEED TO MONITOR CLOSELY. THE MAIN HAZARD WOULD BE DAMAGING WINDS BUT ISOLATED TORNADOES CAN/T BE RULED OUT EITHER AS HELICITY LOOKS TO INCREASE DURING THE DAY AS A SECONDARY WAVE OF LOW PRESSURE TRIES TO DEVELOP ACROSS NORTHEAST GA/UPSTATE SC. THE SEVERE THREAT COULD LINGER INTO THE EVENING AS WELL BEFORE THE TRAILING COLD FRONT PUSHES TOWARD THE COAST AROUND DAYBREAK TUESDAY. EVEN OUTSIDE ANY STORMS IT WILL BE BREEZY MONDAY AFTERNOON GIVEN THE STRENGTH OF THE PRESSURE GRADIENT AND LOW-LEVEL JET /AROUND 45 TO 50 MPH AT ABOUT 2K FT/. THERE IS THE POTENTIAL FOR WINDS TO BE NEAR ADVISORY LEVELS...ESPECIALLY ALONG THE SC COAST. LAKE WINDS...BREEZY CONDITIONS EXPECTED MONDAY AHEAD OF A COLD FRONT. MIXING SHOULD BE MAXIMIZED ALONG THE LAKE SHORES CLOSER TO THE WARMER LAND AREAS. A LAKE WIND ADVISORY MAY EVENTUALLY BE NEEDED TO ACCOUNT FOR SUSTAINED WINDS AROUND 20 KT AND/OR GUSTS TO 25-30 KT. TUESDAY AND WEDNESDAY...COULD SEE SOME SHOWERS LINGER NEAR THE COAST EARLY TUESDAY MORNING DEPENDING ON HOW QUICKLY THE FRONT PASSES...THEN SOME ADDITIONAL SHOWERS COULD DEVELOP DURING THE AFTERNOON AND/OR EVENING AS THE DEEP UPPER TROUGH APPROACHES ALONG WITH FAVORABLE JET FORCING. TEMPERATURES SHOULD REACH THE LOWER TO MID 70S TUESDAY BUT ONLY BE AROUND 70 WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... SURFACE HIGH PRESSURE WILL SLIDE OVER THE AREA WEDNESDAY NIGHT SETTING UP PRETTY GOOD RADIATIONAL COOLING CONDITIONS AND INLAND LOCALES SHOULD DROP INTO THE LOWER TO MID 40S...POSSIBLY SOME UPPER 30S IN THE NORMALLY COLDER SPOTS. A WARMING TREND WILL THEN SET UP THROUGH THE END OF THE WEEK AS THE HIGH SHIFTS EASTWARD INTO THE ATLANTIC SETTING UP A MORE SOUTHERLY FLOW. NO SIGNIFICANT RAIN CHANCES ARE EXPECTED THROUGH THE WEEKEND. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... CONDITIONS EXPECTED TO DETERIORATE TODAY...WITH LOWER CIGS AND VSBYS IN SUBSTANTIAL RAINS AT KSAV. WE MAINTAINED SIMILAR TAF TRENDS TO MVFR/IFR CIGS DEVELOPING AT THE TERMINALS LATER THIS MORNING AS RAINS BECOME MORE PREVALENT. LATEST MODELS SUGGESTING KCHS MAY BE SLOW TO BOTH PRECIPITATE...BUT ALREADY WE ARE SEEING LOW CLOUDS DEVELOPING WITH MOISTURE CONVERGENCE INCREASING. WE TRENDED KCHS A BIT MORE OPTIMISTIC WITH RESPECT TO PREVAILING RAINS FOR SEVERAL HOURS. MODELS CONTINUE TO SUGGEST STRATUS SHOULD BUILD-DOWN IN THE WAKE OF THE MID LEVEL SHORT WAVE AND WE HAVE TRENDED IFR IN THE TONIGHT PERIOD AT BOTH TERMINALS WITH HIGHER CONFIDENCE FROM FORECAST SOUNDINGS AT KSAV. EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CEILINGS AND/OR VISIBILITIES EXPECTED INTO MONDAY AS PLENTY OF LOW-LEVEL MOISTURE REMAINS IN PLACE. SOME IMPROVEMENT WILL OCCUR MONDAY AS A WARM FRONT SHIFTS NORTHWARD THROUGH THE AREA. HOWEVER...IT WILL ONLY BE TEMPORARY AS MOISTURE INCREASES AGAIN LATE MONDAY INTO TUESDAY MORNING AHEAD OF A COLD FRONT. THERE WILL ALSO BE A RISK FOR HEAVY SHOWERS AND A FEW TSTMS...AS WELL AS BREEZY CONDS MONDAY AFTERNOON INTO TUESDAY. GENERALLY VFR WED-FRI. && .MARINE... BACKDOOR COLD FRONT NOSING OUT OF THE PEE DEE INTO THE CHARLESTON COUNTY WATERS EARLY THIS MORNING BUT UPSTREAM PINCHING AND SURGING HAS BEEN SOMEWHAT LESS THAN EXPECTED TO THIS POINT. SMALL CRAFT ADVISORIES FOR SOUTH CAROLINA WATERS WILL STILL BEGIN AT 12Z THIS MORNING BUT THE ONSET OF BETTER PINCHING WITH THE THERMAL/MOISTURE GRADIENT AND DEVELOPING SURFACE WEDGE MAY HOLD OFF UNTIL LATE MORNING OR EVEN THIS AFTERNOON. MARGINAL SCA CONDITIONS WERE MAINTAINED INTO THIS EVENING ALONG COASTAL CHARLESTON COUNTY. THE MESOSCALE GRADIENT LOOKS VERY TRICKY FOR THIS PARTICULAR EVENT AND WE MADE ONLY SLIGHT OVERALL ADJUSTMENTS TO THE PREVIOUS FORECAST. WINDS WILL REMAIN ONSHORE TONIGHT WITH SEAS 3-5 FT ON AVERAGE. MONDAY THROUGH FRIDAY...A WARM FRONT WILL LIFT NORTHWARD THROUGH THE WATERS MONDAY MORNING. STRENGTHENING LOW PRESSURE SHIFTING NORTHEAST INTO THE OHIO VALLEY WILL CAUSE WINDS TO PICK UP LOCALLY WITH ADVISORIES LIKELY FOR AT LEAST THE WATERS BEYOND 20 NM AND IN CHARLESTON HARBOR. THE FRONT WILL PUSH OFFSHORE TUESDAY MORNING WITH WINDS REMAINING ELEVATED INTO WEDNESDAY GIVEN THE PRESSURE GRADIENT AND COLD ADVECTION...LIKELY PEAKING TUESDAY NIGHT. IMPROVING CONDITIONS THEN ON TAP LATER WEDNESDAY AND CONTINUING THROUGH FRIDAY WITH NO HEADLINES EXPECTED. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR AMZ352. SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR AMZ350. && $$ SYNOPSIS... NEAR TERM... SHORT TERM...RJB LONG TERM...RJB AVIATION... MARINE...RJB
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
424 AM EDT SUN APR 6 2014 .SYNOPSIS... A WEAK BACKDOOR COLD FRONT WILL STALL SOUTH OF THE AREA TODAY THEN LIFT NORTH AS A WARM FRONT LATER TONIGHT AND MONDAY MORNING. A STRONGER COLD FRONT WILL MOVE THROUGH THE REGION MONDAY NIGHT FOLLOWED BY AN UPPER LEVEL DISTURBANCE TUESDAY NIGHT. COOLER AND DRIER HIGH PRESSURE WILL THEN PREVAIL THROUGH THURSDAY BEFORE MILDER WEATHER RETURNS AS THE HIGH MOVES OFFSHORE. && .NEAR TERM /THROUGH TONIGHT/... PRE-DAWN...WEAK SURFACE FRONT STALLED ACROSS THE NORTHERN TIER OF SOUTHERN SOUTH CAROLINA AT 07Z WILL BEGIN TO SAG SOUTH BY DAYBREAK AS HIGH PRES BUILDS INTO THE MID ATLC REGION SETTING UP A WEDGE PATTERN...ESPECIALLY SINCE RAINFALL IS EXPECTED TO EXPAND OVER THE COOLER LOW LEVEL AIR SPILLING SOUTH TO THE LEE OF THE MOUNTAINS. A LEAD BATCH OF RAINS ALONG THE ALTAMAHA RIVER REGION A PRE-CURSOR OF MORE SIGNIFICANT RAINS ON THE WAY TODAY FOR SE GEORGIA. AS THE FRONT SINKS S...MILDER TEMPS SHOULD FINALLY BEGIN TO FALL...MOST NOTICEABLY OVER INLAND SE SOUTH CAROLINA. TODAY...QUITE A COMPLEX FORECAST SCENARIO TODAY BUT THE OVERALL PICTURE REMAINS UNCHANGED AS DEEP MOISTURE ADVECTS E AND ENE FROM THE NORTHERN GULF COAST ACROSS SE GEORGIA AND EXTREME SOUTHERN SOUTH CAROLINA TODAY. PWATS IN EXCESS OF 1.5 INCHES WILL ACCOMPANY AN ENERGETIC MID LEVEL SHORT WAVE WHICH HAS BEEN PRODUCING COPIOUS ELEVATED CONVECTIVE RAINS OVERNIGHT ACROSS THE LOWER GULF COAST REGION. INCREASING ISENTROPIC ASCENT AND UPPER FORCING/DIFLUENCE PROGGED TO FOCUS A REGION OF MODERATE RAINS WITH LOCALLY HEAVY ELEVATED CONVECTIVE RAINS ALONG AND SOUTH OF I-16 LATER THIS MORNING INTO AT LEAST MID AFTERNOON. MANY OF THE 00Z MODELS SPIT OUT OVER AN INCH OF RAIN FROM METTER TO STATESBORO AND SAVANNAH/BEAUFORT WITH THE 00Z ECMWF THE OUTLIER MODEL WITH THE LOWEST QPF TALLIES ACROSS OUR REGION...AROUND 1/2 INCH IN GEORGIA. CATEGORICAL POPS MOST AREAS TODAY WITH SOME DRIER AIR HANGING TOUGH ACROSS THE NORTHERN HALF OF THE CHARLESTON TRI-COUNTY AREA MAYBE KEEPING RAIN COVERAGE/AMOUNTS LOWER FROM ABOUT ST. GEORGE TO JAMESTOWN. MODELS DO NOT SHOW MUCH ELEVATED INSTABILITY BUT GIVEN ONGOING UPSTREAM TRENDS AND RAP ANALYSIS...WE FELT THAT A SLIGHT CHANCE OF ELEVATED TSTMS WAS WORTH A MENTION S OF I-16. WITH THE WEDGE PATTERN DIGGING IN AND PLENTY OF RAINFALL...TEMPS WILL LIKELY BE LOWER MUCH OF THE DAY THAN CURRENT READINGS WE ARE SEEING OVERNIGHT WHICH MAKES FOR PROBLEMATIC TEMP FORECASTING AS ATYPICAL DIURNAL CURVES AND STEADY READINGS LIKELY THE STORY FOR THE LATE MORNING AND AFTERNOON HOURS. THE BULK OF THE UPPER FORCING WILL SHIFT OFF THE COAST LATE TODAY AND TONIGHT WITH LOWER CHANCES FOR SOME SHOWERS WITH THE WARM FRONT AND PERHAPS SOME DRIZZLY WEATHER AT TIMES. LOW STRATUS WILL LIKELY EXPAND UNDER THE WEDGE INVERSION WITH LOW TEMPS IN THE MID 50S NORTH TO LOWER 60S ALONG THE SE GEORGIA COAST. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... MONDAY...A WARM FRONT WILL SHIFT NORTH THROUGH THE AREA MONDAY MORNING PLACING THE FORECAST AREA IN THE WARM SECTOR OF THE STRENGTHENING STORM SYSTEM MOVING NORTHEAST INTO THE OHIO VALLEY. ABUNDANT MOISTURE WILL BE MOVING INTO THE AREA AHEAD OF THE TRAILING COLD FRONT. MOSTLY EXPECT SOME MORNING SHOWERS NEAR THE WARM FRONT ACROSS SOUTHERN SOUTH CAROLINA WITH RAIN CHANCES INCREASING FROM THE WEST DURING THE AFTERNOON. THERE SHOULD BE A GOOD BIT OF HIGH CLOUDS WHICH WILL LIMIT HEATING SOMEWHAT AND THIS WILL LIKELY PLAY INTO THE AMOUNT OF INSTABILITY AND VERTICAL MIXING THAT WILL OCCUR. WE REMAIN IN A SLIGHT RISK AREA FOR SEVERE STORMS SO WILL NEED TO MONITOR CLOSELY. THE MAIN HAZARD WOULD BE DAMAGING WINDS BUT ISOLATED TORNADOES CAN/T BE RULED OUT EITHER AS HELICITY LOOKS TO INCREASE DURING THE DAY AS A SECONDARY WAVE OF LOW PRESSURE TRIES TO DEVELOP ACROSS NORTHEAST GA/UPSTATE SC. THE SEVERE THREAT COULD LINGER INTO THE EVENING AS WELL BEFORE THE TRAILING COLD FRONT PUSHES TOWARD THE COAST AROUND DAYBREAK TUESDAY. EVEN OUTSIDE ANY STORMS IT WILL BE BREEZY MONDAY AFTERNOON GIVEN THE STRENGTH OF THE PRESSURE GRADIENT AND LOW-LEVEL JET /AROUND 45 TO 50 MPH AT ABOUT 2K FT/. THERE IS THE POTENTIAL FOR WINDS TO BE NEAR ADVISORY LEVELS...ESPECIALLY ALONG THE SC COAST. LAKE WINDS...BREEZY CONDITIONS EXPECTED MONDAY AHEAD OF A COLD FRONT. MIXING SHOULD BE MAXIMIZED ALONG THE LAKE SHORES CLOSER TO THE WARMER LAND AREAS. A LAKE WIND ADVISORY MAY EVENTUALLY BE NEEDED TO ACCOUNT FOR SUSTAINED WINDS AROUND 20 KT AND/OR GUSTS TO 25-30 KT. TUESDAY AND WEDNESDAY...COULD SEE SOME SHOWERS LINGER NEAR THE COAST EARLY TUESDAY MORNING DEPENDING ON HOW QUICKLY THE FRONT PASSES...THEN SOME ADDITIONAL SHOWERS COULD DEVELOP DURING THE AFTERNOON AND/OR EVENING AS THE DEEP UPPER TROUGH APPROACHES ALONG WITH FAVORABLE JET FORCING. TEMPERATURES SHOULD REACH THE LOWER TO MID 70S TUESDAY BUT ONLY BE AROUND 70 WEDNESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... SURFACE HIGH PRESSURE WILL SLIDE OVER THE AREA WEDNESDAY NIGHT SETTING UP PRETTY GOOD RADIATIONAL COOLING CONDITIONS AND INLAND LOCALES SHOULD DROP INTO THE LOWER TO MID 40S...POSSIBLY SOME UPPER 30S IN THE NORMALLY COLDER SPOTS. A WARMING TREND WILL THEN SET UP THROUGH THE END OF THE WEEK AS THE HIGH SHIFTS EASTWARD INTO THE ATLANTIC SETTING UP A MORE SOUTHERLY FLOW. NO SIGNIFICANT RAIN CHANCES ARE EXPECTED THROUGH THE WEEKEND. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... CONDITIONS EXPECTED TO DETERIORATE TOWARD DAYBREAK...IF NOT A BIT SOONER AT KSAV WHERE RAINS WILL BE DEVELOPING AFTER 09Z. WE MAINTAINED SIMILAR TRENDS TO MVFR/IFR CIGS DEVELOPING AT THE TERMINALS THIS MORNING AS RAINS BECOME MORE PREVALENT. MODELS IN GOOD AGREEMENT IN STEADIEST/HEAVIER RAINS AT KSAV AND THAT IS WHERE WE INTRO IFR CIGS INITIALLY TODAY. BY LATE AFTERNOON AND THROUGH THIS EVENING...MODELS SUGGEST STRATUS SHOULD BUILD-DOWN IN THE WAKE OF THE MID LEVEL SHORT WAVE AND WE HAVE TRENDED IFR IN THE LATER PART OF 06Z TAF CYCLE. EXTENDED AVIATION OUTLOOK...MVFR OR LOWER CEILINGS AND/OR VISIBILITIES EXPECTED INTO MONDAY AS PLENTY OF LOW-LEVEL MOISTURE REMAINS IN PLACE. SOME IMPROVEMENT WILL OCCUR MONDAY AS A WARM FRONT SHIFTS NORTHWARD THROUGH THE AREA. HOWEVER...IT WILL ONLY BE TEMPORARY AS MOISTURE INCREASES AGAIN LATE MONDAY INTO TUESDAY MORNING AHEAD OF A COLD FRONT. THERE WILL ALSO BE A RISK FOR HEAVY SHOWERS AND A FEW TSTMS...AS WELL AS BREEZY CONDS MONDAY AFTERNOON INTO TUESDAY. GENERALLY VFR WED-FRI. && .MARINE... BACKDOOR COLD FRONT NOSING OUT OF THE PEE DEE INTO THE CHARLESTON COUNTY WATERS EARLY THIS MORNING BUT UPSTREAM PINCHING AND SURGING HAS BEEN SOMEWHAT LESS THAN EXPECTED TO THIS POINT. SMALL CRAFT ADVISORIES FOR SOUTH CAROLINA WATERS WILL STILL BEGIN AT 12Z THIS MORNING BUT THE ONSET OF BETTER PINCHING WITH THE THERMAL/MOISTURE GRADIENT AND DEVELOPING SURFACE WEDGE MAY HOLD OFF UNTIL LATE MORNING OR EVEN THIS AFTERNOON. MARGINAL SCA CONDITIONS WERE MAINTAINED INTO THIS EVENING ALONG COASTAL CHARLESTON COUNTY. THE MESOSCALE GRADIENT LOOKS VERY TRICKY FOR THIS PARTICULAR EVENT AND WE MADE ONLY SLIGHT OVERALL ADJUSTMENTS TO THE PREVIOUS FORECAST. WINDS WILL REMAIN ONSHORE TONIGHT WITH SEAS 3-5 FT ON AVERAGE. MONDAY THROUGH FRIDAY...A WARM FRONT WILL LIFT NORTHWARD THROUGH THE WATERS MONDAY MORNING. STRENGTHENING LOW PRESSURE SHIFTING NORTHEAST INTO THE OHIO VALLEY WILL CAUSE WINDS TO PICK UP LOCALLY WITH ADVISORIES LIKELY FOR AT LEAST THE WATERS BEYOND 20 NM AND IN CHARLESTON HARBOR. THE FRONT WILL PUSH OFFSHORE TUESDAY MORNING WITH WINDS REMAINING ELEVATED INTO WEDNESDAY GIVEN THE PRESSURE GRADIENT AND COLD ADVECTION...LIKELY PEAKING TUESDAY NIGHT. IMPROVING CONDITIONS THEN ON TAP LATER WEDNESDAY AND CONTINUING THROUGH FRIDAY WITH NO HEADLINES EXPECTED. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 5 PM EDT THIS AFTERNOON FOR AMZ352. SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 11 PM EDT THIS EVENING FOR AMZ350. && $$ SYNOPSIS... NEAR TERM... SHORT TERM...RJB LONG TERM...RJB AVIATION... MARINE...RJB
AREA FORECAST DISCUSSION
NWS POCATELLO ID
901 AM MDT SUN APR 6 2014 .UPDATE...SHOWERS CONTINUE THIS MORNING MAINLY ACROSS HIGHER ELEVATIONS. AREA WEB CAMS SHOWING LIGHT SNOWFALL BUT NO ACCUMULATIONS ON ROADWAYS. THIS TREND SHOULD CONTINUE THROUGH THE DAY AS SHORTWAVE CROSSING NORTHERN PANHANDLE INTO WESTERN MONTANA. AIR MASS WEAKLY UNSTABLE BUT NOT ENOUGH TO WARRANT ADDING ISOLATED THUNDER TO GRIDS FOR THIS AFTERNOON. TIMING OF SHORTWAVE STILL LOOKS TO MOSTLY EXIT EASTERN IDAHO THIS EVENING THOUGH LATEST NAM RUN HOLDING ON TO WEAK POCKETS OF QPF ALONG DIVIDE AND WYOMING BORDER AFTER 06Z. WINDS STILL MAIN CONCERN TODAY THOUGH EVEN RECENT GUIDANCE BACKING OFF BELOW ADVISORY CRITERIA FOR THIS AFTERNOON. HAVE NUDGED WINDS TOWARD LATEST HRRR WITH GOOD REPRESENTATION OF CANYON OUTFLOW FROM CENTRAL MOUNTAINS TO UPPER SNAKE PLAIN THIS AFTERNOON AND STRONGEST WINDS IN THE MAGIC VALLEY AND SOUTHERN HIGHLANDS...STILL WELL BELOW ADVISORY CRITERIA. REMAINDER OF GRID PACKAGE REASONABLE FOR TODAY. NO OTHER UPDATES ANTICIPATED AT THIS TIME. DMH && .PREV DISCUSSION... /ISSUED 314 AM MDT SUN APR 6 2014/ SHORT TERM...TODAY THROUGH TUESDAY NIGHT. UPPER LEVEL SHORT WAVE IN NORTHWEST FLOW DROPPING SOUTH TODAY AND EXPECT SHOWERS MAINLY IN THE MOUNTAINS TODAY. SNOW ACCUMULATIONS MAINLY IN THE 1 TO 2 INCH RANGE IN CENTRAL MOUNTAINS AND EASTERN HIGHLANDS. WEAK COLD FRONT PUSHING THROUGH AS WELL AND EXPECT BREEZY CONDITIONS TODAY AS WELL BEHIND FRONT MAINLY IN SNAKE RIVER PLAIN. THINK FOR THE MOST PART IT WILL STAY UNDER ADVISORY LEVELS IN MOST AREAS. UPPER RIDGE BUILDS IN MONDAY THROUGH TUESDAY WITH DRY CONDITIONS EXPECTED WITH TEMPERATURES WARMING TO WELL ABOVE SEASONAL NORMALS MONDAY THROUGH TUESDAY WITH WINDS NOR NEARLY AS STRONG AS TODAY. GK LONG TERM...WEDNESDAY THROUGH NEXT SUNDAY. GFS/ECMWF SUGGEST THAT A PASSING DISTURBANCE WILL CLIP THE REGION WEDNESDAY SUPPORTING A CHANCE/SLIGHT CHANCE MENTION OF THUNDERSTORMS FAVORING THE CNTRL AND NE MOUNTAINS. LINGERING SHOWERS WILL PERSIST ACROSS THE MOUNTAINS IN THE MOIST WNW FLOW ALOFT THURSDAY FOLLOWED BY YET ANOTHER PACIFIC DISTURBANCE EITHER FRIDAY (GFS) OR FRIDAY NIGHT/SATURDAY (ECMWF) WHICH LINGERS THROUGH THE WEEKEND. BOTH MODELS SHOW AN AMPLIFYING RIDGE ALONG THE COAST SATURDAY/SUNDAY WITH THE GFS FAVORING A BACKDOOR TROUGH ROTATING INTO THE DAKOTAS AND BANKING UP AGAINST THE MONTANA/WYOMING DIVIDE IN A NE UPSLOPE LOW LEVEL FLOW. THE ECMWF ON THE OTHER HAND IS FURTHER WEST WITH THE BACKDOOR TROUGH AND CONSEQUENTLY IS ADVERTISING A BROAD AREA OF SHOWERS ACROSS SRN IDAHO SATURDAY/SATURDAY NIGHT BEFORE A COLD AND DRY NORTH FLOW SPREADS OVER THE AREA SUNDAY. PREFERENCE HERE IS THE WARMER/DRIER GFS. HUSTON AVIATION...A PACIFIC DISTURBANCE WAS NOTED DIGGING SE INTO THE NRN ROCKIES EARLY THIS MORNING. NUMERICAL MODELS SUGGEST AN INCREASING POTENTIAL FOR SHOWERS FAVORING THE ERN MOUNTAINS THIS AFTERNOON AS THE WAVE SHEARS THROUGH THE REGION. DRIER CONDITIONS FOLLOW OVERNIGHT AS A RIDGE POSITIONED ALONG THE COAST EDGES INLAND. MODEL CROSS SECTIONS SUGGEST THE POTENTIAL FOR MVFR CIGS AT THE TERMINAL SITES...BELIEVE KIDA/KPIH AND KBYI MAY BE MOST AT RISK FOR THIS WITH UPSLOPE WNW FLOW THIS AFTERNOON...ALTHOUGH KSUN NOT TOTALLY OUT OF THE MIX. MESO-SCALE WRF MODEL SUGGESTS THE POTENTIAL FOR A CONVERGENCE SNOW EVENT WORKING OUT OF THE ARCO REGION AROUND 19Z AND SPREADING INTO KIDA AND KPIH 20-23Z WITH ENHANCED SHOWER ACTIVITY/LOWER CIGS. ACCOMPANYING INSTABILITY MAY BOOST THE POTENTIAL FOR A FEW LIGHTNING STRIKES AND SNOW SHOWERS WITH THE CONVERGENCE AREA. HUSTON && .PIH WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
638 PM CDT MON APR 7 2014 .SHORT TERM /TONIGHT/... ISSUED AT 347 PM CDT MON APR 7 2014 WEAKENING TROUGH MOVING INTO THE STATE HAS ALL BUT DISSIPATED AS A NEW TROUGH HAS DEVELOPED FROM SURFACE LOW IN SRN INDIANA. WEAK SHEAR IN PLACE...BUT ABOUT 500 J/KG HAS BEEN ENOUGH TO SET OFF A FEW THUNDERSTORMS. HAIL CAPE IN THE 100 TO 200 J/KG RANGE. WITH LOW FREEZING LEVELS HAVE HAD HAIL UP TO DIME SIZE IN CARROLL COUNTY THIS AFTERNOON AND A QUICK 0.7 INCHES OF RAIN IN THE JEFFERSON AREA. EXPECT THESE TO DISSIPATE WITH SUNSET. SKIES GRADUALLY CLEARING OUT FOR A WHILE BEFORE SOME STRATUS DEVELOPS LATE TONIGHT. .LONG TERM /TUESDAY THROUGH MONDAY/... ISSUED AT 347 PM CDT MON APR 7 2014 LITTLE CHANGES IN THE OVERALL FORECAST WITH LATEST TRENDS ALREADY CAPTURED WELL IN THE PREVIOUS FORECAST PACKAGE. STILL LOOKING SLIGHTLY COOLER FOR TUESDAY...WITH SOME HIGHER CLOUD COVER INITIALLY AS A WEAK SHORTWAVE IS QUICKLY EXITING THE STATE INITIALLY. SFC HIGH PRESSURE TO BUILD INTO THE AREA LATE TUESDAY INTO TUESDAY NIGHT...WITH STRONG WAA STILL ON TAP FOR WEDNESDAY WITH TEMPS IN THE 70S STILL EXPECTED ACROSS MUCH OF THE STATE. BIGGEST ISSUE WEDNESDAY IS WINDS WILL BE BREEZY WITH SUSTAINED WINDS AROUND 20 MPH OR SLIGHTLY HIGHER...AND HIGHER GUSTS. SOME DRIER AIR ALSO EXPECTED TO MIX DOWN TO THE SURFACE IN THE AFTERNOON...SUGGESTING RH VALUES COULD DROP INTO THE 25 TO 35 PERCENT RANGE ACROSS PORTIONS OF THE CWA. THIS WILL CREATE MARGINAL ELEVATED FIRE WEATHER DANGER...SO THESE CONDITIONS WILL CONTINUE TO BE MONITORED. FRONTAL BOUNDARY TO DROP THROUGH THE STATE LATE WEDNESDAY NIGHT INTO EARLY THURSDAY AS THE MAIN BROAD UPPER LEVEL TROUGH SWINGS THROUGH THE GREAT LAKES REGION. BEST FORCING WILL BE CLOSER TO THE UPPER LEVEL SYSTEM AND MOISTURE IS VERY LIMITED...SO ONLY HAVE SOME SLIGHT CHANCE POPS FOR LATE WEDNESDAY NIGHT/EARLY THURSDAY ACROSS THE NORTH/NORTHEASTERN CWA. REMAINDER OF CWA MAY ONLY SEE SOME INCREASED MID/HIGH CLOUDS WITH THE FRONTAL PASSAGE. SOUTHERLY FLOW TO QUICKLY KICK BACK IN BY LATE THURSDAY INTO FRIDAY AHEAD OF A STRONGER UPPER LEVEL TROUGH EXPECTED TO DIG INTO THE REGION SATURDAY INTO SUNDAY. THIS SYSTEM TO BRING THE BEST CHANCE OF PRECIP TO MUCH OF THE CWA INTO THE WEEKEND AS THETA-E ADVECTION ORIENTED RIGHT INTO THE CWA SATURDAY INTO SATURDAY EVENING AS THE ASSOCIATED SFC TROUGH AXIS/COLD FRONT DROPS INTO IOWA. SCATTERED TO WIDESPREAD THUNDERSTORM ACTIVITY EXPECTED SATURDAY EVENING INTO THE OVERNIGHT...AND WILL HAVE TO MONITOR FOR SEVERE POTENTIAL AS THE DAY APPROACHES AS WELL. GFS REMAINS MORE PROGRESSIVE WITH THIS SYSTEM SHOVING THE FRONT WELL SOUTH OF THE CWA SUNDAY WITH MUCH COLDER AIR PUSHING INTO THE REGION FOR EARLY NEXT WEEK. EC REMAINS SLOWER WITH THE SYSTEM...AND KEEPS THE FRONT STRETCHED ACROSS THE CWA INTO SUNDAY WITH IT PUSHING SOUTH OF THE CWA BY LATE SUNDAY NIGHT. THIS SCENARIO HAS ENERGY DIGGING INTO THE BACKSIDE OF THE TROUGH TO CONTINUE PRECIP CHANCES ALONG THE FRONT WITH POSSIBILITY OF A LARGE AREA OF STRATIFORM RAIN TO REMAIN ACROSS THE AREA SUNDAY...WITH SOME RAIN MIXING WITH SNOW AS COLDER AIR MOVES INTO THE AREA SUNDAY NIGHT. FOR NOW HAVE SPLIT THE SCENARIOS...WITH SOME CHANCE POPS LINGERING INTO SUNDAY/SUNDAY NIGHT WITH THE HIGHEST POPS SATURDAY NIGHT AS THE FRONT ENTERS THE CWA. TEMPS LOOK TO FALL TO NEAR OR SLIGHTLY COOLER THAN THE SEASONAL AVERAGES INTO EARLY NEXT WEEK AS H85 TEMPS FALL BELOW FREEZING AGAIN. && .AVIATION...08/00Z ISSUED AT 634 PM CDT MON APR 7 2014 BAND OF SHOWERS WILL DEPART THIS EVENING WITH GENERALLY VFR CONDITIONS OVERNIGHT. RAP AND NAM WERE SUGGESTING LOW LEVEL MVFR CLOUDS MOVING INTO FAR NORTHWEST IOWA AFTER 09Z AND SPREADING SOUTHEAST AHEAD OF SECONDARY UPPER TROF INTO TUESDAY MORNING. HAVE INCLUDED SOME OF THIS IN THE TAFS...BUT HAVE LEFT CEILING VFR AT THIS TIME. WINDS WILL INCREASE FROM THE NORTHWEST ONCE AGAIN ON TUESDAY AS DAYTIME LOW LEVEL MIXING INCREASES. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...MS APR 14 LONG TERM...BEERENDS AVIATION...COGIL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1224 PM CDT SUN APR 6 2014 .SYNOPSIS... ISSUED AT 250 AM CDT SUN APR 6 2014 MID AND HIGH CLOUDS ARE SPREADING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH MOVING INTO THE PLAINS. LOW-LEVEL FLOW CONTINUES TO PUSH WARMER AIR INTO THE CWA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 250 AM CDT SUN APR 6 2014 LOOKS LIKE A GENERALLY DRY PERIOD THROUGH THIS TIME FRAME DESPITE THE OUTLIER GFS FORECAST OF PRECIP. LOW-LEVEL DRY AIR APPARENT ON THE 00Z OUN AND DDC SOUNDINGS IS INDICATIVE OF THE LOW-LEVEL DRY AIR THAT WILL NEED TO BE OVERCOME BEFORE ANY PRECIP DEVELOPS. IN ADDITION...THE SYNOPTIC MODELS...AND IN PARTICULAR THE GFS...ARE TOO HIGH WITH THEIR SURFACE DEW POINT INITIALIZATIONS IN THE CENTRAL PLAINS. ALSO HRRR AND HOPWRF REFLECTIVITY PROGS SUGGEST ANY PRECIP THAT WOULD DEVELOP WOULD BE SPRINKLES...IF INDEED ANYTHING WERE TO EVEN DEVELOP IN THE CWA AT ALL. CONTINUING WARM ADVECTION OVERNIGHT SHOULD BALANCE LOSS OF FULL SUNSHINE WITH INCREASING CLOUDS TODAY SUCH THAT TEMPS WILL BE SEVERAL DEGREES WARMER THAN SATURDAY. DOWNSTREAM TEMPS AND FORECAST SOUNDINGS INDICATE SOME SPOTS IN THE SOUTHWEST PORTION OF THE CWA COULD EXCEED 60 DEGREES. WITH THE EXTENSIVE CLOUD COVER...LOWS TONIGHT WILL MODERATE OVER THIS MORNING`S READINGS WITH MOSTLY 40S AND A FEW UPPER 30S ACROSS THE CWA. WOLF .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 250 AM CDT SUN APR 6 2014 FORECAST FOCUS ON NICE WARM-UP THIS UPCOMING WEEK WITH NO SIGNIFICANT RAIN. GFS CONTINUES TO BE THE OUTLIER FOR THE STORM SYSTEM ON MONDAY. MODELS ARE TOO HIGH WITH DEW POINTS IN THIS CURRENT REGIME COMPARED TO REALITY AND HAVE LOWERED VALUES SOMEWHAT THROUGHOUT THIS EXTENDED PERIOD. MONDAY AND MONDAY NIGHT...THE GFS IS THE FARTHEST NORTHWEST WITH THE INTENSIFYING CYCLONE TRACKING OUT OF THE WESTERN GULF AND INTO THE OHIO VALLEY. FOR NOW THIS HAS BEEN DISCOUNTED AS OTHER MODELS AGREE ON KEEPING THE SIGNIFICANT RAIN EAST AND SOUTH OF THE DVN CWA. WILL CONTINUE WITH SMALL POPS AS NORTHERN STREAM UPPER LEVEL TROUGH SWINGS ACROSS THE AREA...BUT LOW LEVEL MOISTURE WILL BE LIMITED. WITH EXTENSIVE CLOUD COVER TEMPERATURES WILL BE IN THE 50S. MID TO LATE WEEK...MODELS HAVE BEEN CONSISTENT SHOWING A STRONG STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA. THIS WILL PULL MILD TO WARM AIR INTO THE MIDWEST ON GUSTY SOUTHWEST WINDS. AFTERNOON TEMPERATURES WILL PUSH WELL INTO THE 60S TO LOWER 70S...AND COMBINED WITH LOW RELATIVE HUMIDITY AND DRY VEGETATION...THERE WILL BE AN ENHANCED RISK FOR GRASS FIRES. WILL BEGIN TO HIGHLIGHT THIS THREAT IN THE HWO PRODUCT EARLY THIS MORNING. WEAK COLD FRONT WILL ARRIVE BY THURSDAY EVENING AND MAY PRODUCE A FEW SHOWERS BUT MOISTURE WILL BE LIMITED. MILD TEMPERATURES IN THE 60S WILL CONTINUE FRIDAY AND SATURDAY AHEAD OF THE NEXT SIGNIFICANT AND INTERESTING STORM SYSTEM. HAASE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1215 PM CDT SUN APR 6 2014 VFR CONDITIONS EXPECTED TO PERSIST THROUGH 18Z MONDAY WITH MOST OF THE AREA RESIDING IN LOW LEVEL DRY WEDGE AND SUBSIDENCE IN BETWEEN PCPN AREAS TO OUR NORTHWEST WITH WEAK FRONTAL ZONE...AND TO OUR SOUTHEAST WITH STORM SYSTEM TRACKING FROM THE TX GULF COAST TO THE OHIO VLY. S/SE WINDS WILL BE NEAR TO JUST ABOVE 10 KTS THIS AFTN THEN DROP BLO 10KTS TNGT INTO MONDAY AM WHILE BACKING TO THE N/NE. MCCLURE && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...WOLF SHORT TERM...WOLF LONG TERM...HAASE AVIATION...MCCLURE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
621 AM CDT SUN APR 6 2014 .SYNOPSIS... ISSUED AT 250 AM CDT SUN APR 6 2014 MID AND HIGH CLOUDS ARE SPREADING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH MOVING INTO THE PLAINS. LOW-LEVEL FLOW CONTINUES TO PUSH WARMER AIR INTO THE CWA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 250 AM CDT SUN APR 6 2014 LOOKS LIKE A GENERALLY DRY PERIOD THROUGH THIS TIME FRAME DESPITE THE OUTLIER GFS FORECAST OF PRECIP. LOW-LEVEL DRY AIR APPARENT ON THE 00Z OUN AND DDC SOUNDINGS IS INDICATIVE OF THE LOW-LEVEL DRY AIR THAT WILL NEED TO BE OVERCOME BEFORE ANY PRECIP DEVELOPS. IN ADDITION...THE SYNOPTIC MODELS...AND IN PARTICULAR THE GFS...ARE TOO HIGH WITH THEIR SURFACE DEW POINT INITIALIZATIONS IN THE CENTRAL PLAINS. ALSO HRRR AND HOPWRF REFLECTIVITY PROGS SUGGEST ANY PRECIP THAT WOULD DEVELOP WOULD BE SPRINKLES...IF INDEED ANYTHING WERE TO EVEN DEVELOP IN THE CWA AT ALL. CONTINUING WARM ADVECTION OVERNIGHT SHOULD BALANCE LOSS OF FULL SUNSHINE WITH INCREASING CLOUDS TODAY SUCH THAT TEMPS WILL BE SEVERAL DEGREES WARMER THAN SATURDAY. DOWNSTREAM TEMPS AND FORECAST SOUNDINGS INDICATE SOME SPOTS IN THE SOUTHWEST PORTION OF THE CWA COULD EXCEED 60 DEGREES. WITH THE EXTENSIVE CLOUD COVER...LOWS TONIGHT WILL MODERATE OVER THIS MORNING`S READINGS WITH MOSTLY 40S AND A FEW UPPER 30S ACROSS THE CWA. WOLF .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 250 AM CDT SUN APR 6 2014 FORECAST FOCUS ON NICE WARM-UP THIS UPCOMING WEEK WITH NO SIGNIFICANT RAIN. GFS CONTINUES TO BE THE OUTLIER FOR THE STORM SYSTEM ON MONDAY. MODELS ARE TOO HIGH WITH DEW POINTS IN THIS CURRENT REGIME COMPARED TO REALITY AND HAVE LOWERED VALUES SOMEWHAT THROUGHOUT THIS EXTENDED PERIOD. MONDAY AND MONDAY NIGHT...THE GFS IS THE FARTHEST NORTHWEST WITH THE INTENSIFYING CYCLONE TRACKING OUT OF THE WESTERN GULF AND INTO THE OHIO VALLEY. FOR NOW THIS HAS BEEN DISCOUNTED AS OTHER MODELS AGREE ON KEEPING THE SIGNIFICANT RAIN EAST AND SOUTH OF THE DVN CWA. WILL CONTINUE WITH SMALL POPS AS NORTHERN STREAM UPPER LEVEL TROUGH SWINGS ACROSS THE AREA...BUT LOW LEVEL MOISTURE WILL BE LIMITED. WITH EXTENSIVE CLOUD COVER TEMPERATURES WILL BE IN THE 50S. MID TO LATE WEEK...MODELS HAVE BEEN CONSISTENT SHOWING A STRONG STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA. THIS WILL PULL MILD TO WARM AIR INTO THE MIDWEST ON GUSTY SOUTHWEST WINDS. AFTERNOON TEMPERATURES WILL PUSH WELL INTO THE 60S TO LOWER 70S...AND COMBINED WITH LOW RELATIVE HUMIDITY AND DRY VEGETATION...THERE WILL BE AN ENHANCED RISK FOR GRASS FIRES. WILL BEGIN TO HIGHLIGHT THIS THREAT IN THE HWO PRODUCT EARLY THIS MORNING. WEAK COLD FRONT WILL ARRIVE BY THURSDAY EVENING AND MAY PRODUCE A FEW SHOWERS BUT MOISTURE WILL BE LIMITED. MILD TEMPERATURES IN THE 60S WILL CONTINUE FRIDAY AND SATURDAY AHEAD OF THE NEXT SIGNIFICANT AND INTERESTING STORM SYSTEM. HAASE && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 617 AM CDT SUN APR 6 2014 VFR CONDITIONS WILL PREVAIL THROUGH 12Z MONDAY...AND RAIN CHANCES SHOULD HOLD OFF UNTIL THAT TIME. UPPER LEVEL TROUGH MOVING INTO THE PLAINS IS PUSHING AN EXTENSIVE AREA OF MID AND HIGH CLOUDS ACROSS THE MIDWEST...BUT NO IMPACT TO AIRPORT OPS IS EXPECTED. SOUTH WINDS WILL EQUAL OR SLIGHTLY EXCEED 10 KTS TODAY...THEN DROP BELOW THAT THRESHOLD AND BACK SLIGHTLY TO SOUTHEAST THIS EVENING. WOLF && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...WOLF SHORT TERM...WOLF LONG TERM...HAASE AVIATION...WOLF
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
311 AM CDT SUN APR 6 2014 .SYNOPSIS... ISSUED AT 250 AM CDT SUN APR 6 2014 MID AND HIGH CLOUDS ARE SPREADING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH MOVING INTO THE PLAINS. LOW-LEVEL FLOW CONTINUES TO PUSH WARMER AIR INTO THE CWA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 250 AM CDT SUN APR 6 2014 LOOKS LIKE A GENERALLY DRY PERIOD THROUGH THIS TIME FRAME DESPITE THE OUTLIER GFS FORECAST OF PRECIP. LOW-LEVEL DRY AIR APPARENT ON THE 00Z OUN AND DDC SOUNDINGS IS INDICATIVE OF THE LOW-LEVEL DRY AIR THAT WILL NEED TO BE OVERCOME BEFORE ANY PRECIP DEVELOPS. IN ADDITION...THE SYNOPTIC MODELS...AND IN PARTICULAR THE GFS...ARE TOO HIGH WITH THEIR SURFACE DEW POINT INITIALIZATIONS IN THE CENTRAL PLAINS. ALSO HRRR AND HOPWRF REFLECTIVITY PROGS SUGGEST ANY PRECIP THAT WOULD DEVELOP WOULD BE SPRINKLES...IF INDEED ANYTHING WERE TO EVEN DEVELOP IN THE CWA AT ALL. CONTINUING WARM ADVECTION OVERNIGHT SHOULD BALANCE LOSS OF FULL SUNSHINE WITH INCREASING CLOUDS TODAY SUCH THAT TEMPS WILL BE SEVERAL DEGREES WARMER THAN SATURDAY. DOWNSTREAM TEMPS AND FORECAST SOUNDINGS INDICATE SOME SPOTS IN THE SOUTHWEST PORTION OF THE CWA COULD EXCEED 60 DEGREES. WITH THE EXTENSIVE CLOUD COVER...LOWS TONIGHT WILL MODERATE OVER THIS MORNING`S READINGS WITH MOSTLY 40S AND A FEW UPPER 30S ACROSS THE CWA. WOLF .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 250 AM CDT SUN APR 6 2014 FORECAST FOCUS ON NICE WARM-UP THIS UPCOMING WEEK WITH NO SIGNIFICANT RAIN. GFS CONTINUES TO BE THE OUTLIER FOR THE STORM SYSTEM ON MONDAY. MODELS ARE TOO HIGH WITH DEW POINTS IN THIS CURRENT REGIME COMPARED TO REALITY AND HAVE LOWERED VALUES SOMEWHAT THROUGHOUT THIS EXTENDED PERIOD. MONDAY AND MONDAY NIGHT...THE GFS IS THE FARTHEST NORTHWEST WITH THE INTENSIFYING CYCLONE TRACKING OUT OF THE WESTERN GULF AND INTO THE OHIO VALLEY. FOR NOW THIS HAS BEEN DISCOUNTED AS OTHER MODELS AGREE ON KEEPING THE SIGNIFICANT RAIN EAST AND SOUTH OF THE DVN CWA. WILL CONTINUE WITH SMALL POPS AS NORTHERN STREAM UPPER LEVEL TROUGH SWINGS ACROSS THE AREA...BUT LOW LEVEL MOISTURE WILL BE LIMITED. WITH EXTENSIVE CLOUD COVER TEMPERATURES WILL BE IN THE 50S. MID TO LATE WEEK...MODELS HAVE BEEN CONSISTENT SHOWING A STRONG STORM SYSTEM TRACKING ACROSS SOUTHERN CANADA. THIS WILL PULL MILD TO WARM AIR INTO THE MIDWEST ON GUSTY SOUTHWEST WINDS. AFTERNOON TEMPERATURES WILL PUSH WELL INTO THE 60S TO LOWER 70S...AND COMBINED WITH LOW RELATIVE HUMIDITY AND DRY VEGETATION...THERE WILL BE AN ENHANCED RISK FOR GRASS FIRES. WILL BEGIN TO HIGHLIGHT THIS THREAT IN THE HWO PRODUCT EARLY THIS MORNING. WEAK COLD FRONT WILL ARRIVE BY THURSDAY EVENING AND MAY PRODUCE A FEW SHOWERS BUT MOISTURE WILL BE LIMITED. MILD TEMPERATURES IN THE 60S WILL CONTINUE FRIDAY AND SATURDAY AHEAD OF THE NEXT SIGNIFICANT AND INTERESTING STORM SYSTEM. HAASE && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 1120 PM CDT SAT APR 5 2014 PLEASANTLY VFR WEATHER WILL LAST THROUGH THE NEXT 24 HOURS PLUS...AS HIGH PRESSURE OVER ILLINOIS SLOWLY MOVES EAST. AS THE HIGH MOVES EAST...WINDS WILL BECOME PREDOMINANTLY SOUTHERLY...WITH SOME HOURS OF SOUTHEASTERLY WINDS POSSIBLE AS WELL THROUGH MID MORNING SUNDAY. ALL CIGS WILL BE 10 KFT OR HIGHER...AS CIRRUS AND MID CLOUDS PASS OVER THE REGION...BUT WITH DRY AIR BELOW THIS LEVEL...NO LOWER CLOUDS OR VISIBILITY RESTRICTIONS ARE EXPECTED. ERVIN && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...WOLF SHORT TERM...WOLF LONG TERM...HAASE AVIATION...ERVIN
AREA FORECAST DISCUSSION
NWS GOODLAND KS
206 PM MDT SUN APR 6 2014 .UPDATE... ISSUED AT 1022 AM MDT SUN APR 6 2014 MODELS PLAYING CATCHUP THIS MORNING. SYSTEM THAT WAS EXPECTED TO BRING RAIN TO THE AREA LAST NIGHT INTO THIS MORNING IS MUCH FURTHER SOUTH THAN ANTICIPATED BY MYSELF AND MODEL OUTPUT. MAIN CHANCE FOR RAINFALL IS SOUTH OF MY AREA WITH A LITTLE BIT OF A CHANCE IN MY FAR SOUTHERN LOCATIONS FOR THE REST OF THIS MORNING. BECAUSE OF THE FURTHER SOUTH SOLUTION THERE IS A LOT LESS CLOUD COVER THAN THE MODELS THOUGHT THERE WOULD BE WHICH WILL ALLOW THE TEMPERATURES TO GET WARMER THAN EXPECTED. RAP WAS DOING A DECENT JOB WITH THIS AND USED FOR THE UPDATE. ALSO DRAMATICALLY REDUCED SKY COVER PER LATEST SATELLITE WITH MODEL OUTPUT HAVING TOO MUCH. SATELLITE AND PV ANALYSIS INDICATE A FAIRLY STRONG SHORTWAVE TROUGH MOVING TOWARD THE AREA FROM THE NORTHWEST. UPSTREAM 12Z SOUNDINGS DO SHOW SOME CAPE IN THIS AIR MASS. ALL MODEL OUTPUT IS SHOWING NEGATIVE THETA-E LAPSE RATES THROUGH MID LEVELS INTO THIS EVENING IN ADDITION TO KEEPING AROUND SURFACE AND ELEVATED CAPE. ALSO A SURFACE TROUGH IS PUSHING THE AREA AND IS ABOUT HALF WAY THROUGH THE AREA AT THIS TIME. SMALL SCALE OUTPUT IS INDICATING THAT THIS BOUNDARY WILL END UP BEING DRAPED OVER SOUTHERN AND EASTERN AREAS BY LATE THIS MORNING. SMALL SCALE OUTPUT IS ALSO GENERATING CONVECTIVE PRECIPITATION. SO ADJUSTED POPS THIS AFTERNOON AND EVENING ACCOUNTING FOR THE ABOVE MENTIONED PARAMETERS. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 303 AM MDT SUN APR 6 2014 AS OF 4 AM CDT...3 AM MDT...SKIES ACROSS THE TRI-STATE AREA WERE MOSTLY CLOUDY. TEMPERATURES HAVE BEEN SLOW TO FALL TONIGHT...COOLING INTO THE UPPER 30S TO MID 40S FOR MOST LOCATIONS. WINDS WERE FROM THE SOUTH AT 10 TO 20 MPH. A DEEP LONGWAVE TROUGH WAS LOCATED OVER THE FOUR CORNERS REGION WITH A SHORTWAVE TROUGH MOVING THROUGH WYOMING AND UTAH. A WEAK SURFACE LOW PRESSURE WAS LOCATED OVER WESTERN NEBRASKA. FOR TODAY...MAIN CONCERNS WITH THE FORECAST ARE THE CHANCES FOR PRECIPITATION AND POSSIBLE THUNDERSTORMS. SHOWERS HAVE DEVELOPED THIS MORNING ALONG A WEAK ELEVATED FRONTAL BAND THAT STRETCHES FROM NEAR PUEBLO...COLORADO TO HAYS...KANSAS. THIS TREND SHOULD CONTINUE THROUGH THE MORNING HOURS. ACTIVITY SO FAR HAS NOT BEEN IMPRESSIVE DUE TO A MORE STABLE ATMOSPHERE THAN PREVIOUSLY EXPECTED SO LOWERED POPS AND QPF FOR THIS MORNING. LATER TODAY...THE SHORTWAVE TROUGH MOVES THROUGH. WITH WARMER TEMPERATURES AND SOME WEAK INSTABILITY... EXPECTING A ROUND OF SHOWERS WITH ISOLATED THUNDERSTORMS TO DEVELOP OVER NORTHEAST COLORADO AND HEAD EAST. OVERALL...CAPE...SHEAR AND LAPSE RATES ARE MEAGER AT BEST. CONSIDERED REMOVING THE MENTION OF ISOLATED THUNDERSTORMS BUT DECIDED TO LEAVE IT IN AS A RUMBLE OF THUNDER OR TWO CAN NOT BE RULED OUT. WITH DENSE CLOUD COVER EXPECTED TODAY...THINK THAT INSTABILITY WILL BE LIMITED SO WIDESPREAD STORMS ARE NOT EXPECTED. FOR TONIGHT...A COLD FRONT PASSES THROUGH. BEHIND THIS FRONT...WINDY CONDITIONS CAN BE EXPECTED THROUGH MONDAY EVENING. MODELS SEEM TO HAVE COME DOWN ON THE POTENTIAL FOR STRONGER GUSTS AS THE WIND FIELD ALOFT IS WEAKER THAN IN PREVIOUS RUNS. HAVE NUDGED WINDS DOWN A COUPLE KNOTS BUT AM STILL FLIRTING WITH WIND ADVISORY CRITERIA. WILL NOT ISSUE A WIND ADVISORY WITH THIS FORECAST RUN AND ONE MAY NOT BE NEEDED AT ALL BASED ON THE LATEST MODEL TRENDS. SO FAR...THE LACK OF PRECIPITATION WOULD MEAN AN INCREASED THREAT OF BLOWING DUST. HOWEVER...WITH WEAKER WINDS EXPECTED...BLOWING DUST WOULD NOT BE A MAJOR THREAT FOR OUR REGION. AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS OVER THE ROCKIES ON MONDAY NIGHT...BRINGING QUIET WEATHER BACK TO THE TRI-STATE AREA. WARMER WEATHER IS ANTICIPATED TO RETURN WITH WARMER 850 MB TEMPS ADVECTING IN FROM THE SOUTHWEST. RELATIVE HUMIDITY VALUES DROP INTO THE 20 TO 25 PERCENT RANGE DUE TO DRY AIR IN PLACE AND WARMER WEATHER ON TUESDAY. HOWEVER...LIGHT WINDS WILL MITIGATE ANY THREAT OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 147 PM MDT SUN APR 6 2014 UPPER RIDGE WILL BEGIN BUILDING OVER THE CENTRAL HIGH PLAINS MONDAY NIGHT AND DOMINATE THROUGH WEDNESDAY. IT WILL BE WARM AND DRY DURING THAT PERIOD. RELATIVE HUMIDITY WILL APPROACH CRITICAL VALUES WEDNESDAY AFTERNOON BUT WINDS WILL BE TOO LIGHT FOR FIRE WEATHER CONCERNS. RIDGE GETS FLATTENED WEDNESDAY NIGHT BY A NORTHERN STREAM SHORTWAVE TROUGH WITH ASSOCIATED SURFACE COLD FRONT MOVING THROUGH DURING THE OVERNIGHT TO EARLY THURSDAY MORNING TIMEFRAME. DO NOT SEE ANY PRECIPITATION WITH THE FRONT. TEMPERATURES ON THURSDAY WILL BE AROUND 10 DEGREES COOLER THAN WEDNESDAY BUT STILL ABOVE NORMAL. RETURN FLOW GETS UNDERWAY BY THURSDAY AFTERNOON AND COULD SEE AN ISOLATED THUNDERSTORM DEVELOP OVER THE HIGHER TERRAIN TO THE WEST IN THE LOW LEVEL UPSLOPE BUT WILL LIKELY BE FADING BY THE TIME IT REACHES YUMA COUNTY IN THE LATE AFTERNOON OR EVENING HOURS WITH LOSS OF SURFACE HEATING. SHORTWAVE RIDGING RETURNS FOR FRIDAY WITH ANOTHER DRY DAY AND ABOVE NORMAL TEMPERATURES. THE WEEKEND WILL PROVIDE THE NEXT OPPORTUNITY FOR SIGNIFICANT PRECIPITATION CHANCES AS A SOUTHERN STREAM SYSTEM GETS ORGANIZED IN THE FOUR CORNERS AND MOVES ACROSS THE CENTRAL PLAINS. SATURDAY MAY PROVIDE THE FIRST REAL OPPORTUNITY FOR SEVERE WEATHER WITH DECENT MOISTURE RETURN...COOLING ALOFT AND WEAK LEAD SHORTWAVE EJECTING AHEAD OF THE MAIN TROUGH. INSTABILITY AXIS WILL SET UP OVER THE EASTERN HALF OF THE LOCAL AREA WITH HIGHEST VALUES FROM HILL CITY TO GOVE BY THE AFTERNOON WITH GFS CURRENTLY SHOWING UP TO 2000 J/KG. HOWEVER...DEEP LAYER SHEAR IS ONLY FORECAST AT AROUND 25KT WHICH WOULD LIMIT STORM ORGANIZATION. STILL A WEEK AWAY BUT MID APRIL TYPICALLY SEES SEVERE WEATHER THREAT INCREASING. SUNDAY PRESENTS YET ANOTHER CONCERN...WITH THE ECMWF AND TO A LESSER EXTENT THE GFS SHOWING MUCH COLDER AIR WRAPPING AROUND THE BACKSIDE AND PRECIPITATION IN THE FORM OF RAIN OR SNOW. ANTECEDENT WARM GROUND CONDITIONS WOULD PROBABLY LIMIT ACCUMULATION POTENTIAL...BUT THEN AGAIN MID APRIL SNOW STORMS ARE NOT UNHEARD OF IN THE HIGH PLAINS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1134 AM MDT SUN APR 6 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. ISOLATED TO POSSIBLY SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS THE AREA THIS AFTERNOON AND CONTINUE INTO EARLY THIS EVENING. DID CHOOSE TO PUT -TSRA AT BOTH SITES BUT IT DOES LOOK LIKE KMCK WILL HAVE THE BEST CHANCE AND THAT IS WHY I PUT IN A MINOR VISIBILITY RESTRICTION. LATER ON TONIGHT...A SURFACE TROUGH FOLLOWED BY A STRONG COLD FRONT WILL PUSH THROUGH THE AREA. NORTH TO NORTHWEST WINDS WILL BE SUSTAINED NEAR 25 KNOTS WITH GUSTS TO NEAR 35 KNOTS FROM NEAR 12Z TO THE END OF THE PERIOD. THESE GUSTY WINDS WILL LAST BEYOND THIS PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...RRH LONG TERM...024 AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1137 AM MDT SUN APR 6 2014 .UPDATE... ISSUED AT 1022 AM MDT SUN APR 6 2014 MODELS PLAYING CATCHUP THIS MORNING. SYSTEM THAT WAS EXPECTED TO BRING RAIN TO THE AREA LAST NIGHT INTO THIS MORNING IS MUCH FURTHER SOUTH THAN ANTICIPATED BY MYSELF AND MODEL OUTPUT. MAIN CHANCE FOR RAINFALL IS SOUTH OF MY AREA WITH A LITTLE BIT OF A CHANCE IN MY FAR SOUTHERN LOCATIONS FOR THE REST OF THIS MORNING. BECAUSE OF THE FURTHER SOUTH SOLUTION THERE IS A LOT LESS CLOUD COVER THAN THE MODELS THOUGHT THERE WOULD BE WHICH WILL ALLOW THE TEMPERATURES TO GET WARMER THAN EXPECTED. RAP WAS DOING A DECENT JOB WITH THIS AND USED FOR THE UPDATE. ALSO DRAMATICALLY REDUCED SKY COVER PER LATEST SATELLITE WITH MODEL OUTPUT HAVING TOO MUCH. SATELLITE AND PV ANALYSIS INDICATE A FAIRLY STRONG SHORTWAVE TROUGH MOVING TOWARD THE AREA FROM THE NORTHWEST. UPSTREAM 12Z SOUNDINGS DO SHOW SOME CAPE IN THIS AIR MASS. ALL MODEL OUTPUT IS SHOWING NEGATIVE THETA-E LAPSE RATES THROUGH MID LEVELS INTO THIS EVENING IN ADDITION TO KEEPING AROUND SURFACE AND ELEVATED CAPE. ALSO A SURFACE TROUGH IS PUSHING THE AREA AND IS ABOUT HALF WAY THROUGH THE AREA AT THIS TIME. SMALL SCALE OUTPUT IS INDICATING THAT THIS BOUNDARY WILL END UP BEING DRAPED OVER SOUTHERN AND EASTERN AREAS BY LATE THIS MORNING. SMALL SCALE OUTPUT IS ALSO GENERATING CONVECTIVE PRECIPITATION. SO ADJUSTED POPS THIS AFTERNOON AND EVENING ACCOUNTING FOR THE ABOVE MENTIONED PARAMETERS. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 303 AM MDT SUN APR 6 2014 AS OF 4 AM CDT...3 AM MDT...SKIES ACROSS THE TRI-STATE AREA WERE MOSTLY CLOUDY. TEMPERATURES HAVE BEEN SLOW TO FALL TONIGHT...COOLING INTO THE UPPER 30S TO MID 40S FOR MOST LOCATIONS. WINDS WERE FROM THE SOUTH AT 10 TO 20 MPH. A DEEP LONGWAVE TROUGH WAS LOCATED OVER THE FOUR CORNERS REGION WITH A SHORTWAVE TROUGH MOVING THROUGH WYOMING AND UTAH. A WEAK SURFACE LOW PRESSURE WAS LOCATED OVER WESTERN NEBRASKA. FOR TODAY...MAIN CONCERNS WITH THE FORECAST ARE THE CHANCES FOR PRECIPITATION AND POSSIBLE THUNDERSTORMS. SHOWERS HAVE DEVELOPED THIS MORNING ALONG A WEAK ELEVATED FRONTAL BAND THAT STRETCHES FROM NEAR PUEBLO...COLORADO TO HAYS...KANSAS. THIS TREND SHOULD CONTINUE THROUGH THE MORNING HOURS. ACTIVITY SO FAR HAS NOT BEEN IMPRESSIVE DUE TO A MORE STABLE ATMOSPHERE THAN PREVIOUSLY EXPECTED SO LOWERED POPS AND QPF FOR THIS MORNING. LATER TODAY...THE SHORTWAVE TROUGH MOVES THROUGH. WITH WARMER TEMPERATURES AND SOME WEAK INSTABILITY... EXPECTING A ROUND OF SHOWERS WITH ISOLATED THUNDERSTORMS TO DEVELOP OVER NORTHEAST COLORADO AND HEAD EAST. OVERALL...CAPE...SHEAR AND LAPSE RATES ARE MEAGER AT BEST. CONSIDERED REMOVING THE MENTION OF ISOLATED THUNDERSTORMS BUT DECIDED TO LEAVE IT IN AS A RUMBLE OF THUNDER OR TWO CAN NOT BE RULED OUT. WITH DENSE CLOUD COVER EXPECTED TODAY...THINK THAT INSTABILITY WILL BE LIMITED SO WIDESPREAD STORMS ARE NOT EXPECTED. FOR TONIGHT...A COLD FRONT PASSES THROUGH. BEHIND THIS FRONT...WINDY CONDITIONS CAN BE EXPECTED THROUGH MONDAY EVENING. MODELS SEEM TO HAVE COME DOWN ON THE POTENTIAL FOR STRONGER GUSTS AS THE WIND FIELD ALOFT IS WEAKER THAN IN PREVIOUS RUNS. HAVE NUDGED WINDS DOWN A COUPLE KNOTS BUT AM STILL FLIRTING WITH WIND ADVISORY CRITERIA. WILL NOT ISSUE A WIND ADVISORY WITH THIS FORECAST RUN AND ONE MAY NOT BE NEEDED AT ALL BASED ON THE LATEST MODEL TRENDS. SO FAR...THE LACK OF PRECIPITATION WOULD MEAN AN INCREASED THREAT OF BLOWING DUST. HOWEVER...WITH WEAKER WINDS EXPECTED...BLOWING DUST WOULD NOT BE A MAJOR THREAT FOR OUR REGION. AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS OVER THE ROCKIES ON MONDAY NIGHT...BRINGING QUIET WEATHER BACK TO THE TRI-STATE AREA. WARMER WEATHER IS ANTICIPATED TO RETURN WITH WARMER 850 MB TEMPS ADVECTING IN FROM THE SOUTHWEST. RELATIVE HUMIDITY VALUES DROP INTO THE 20 TO 25 PERCENT RANGE DUE TO DRY AIR IN PLACE AND WARMER WEATHER ON TUESDAY. HOWEVER...LIGHT WINDS WILL MITIGATE ANY THREAT OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 224 AM MDT SUN APR 6 2014 UPPER LEVEL RIDGE WILL MAINTAIN DOMINANCE OF THE WEATHER ACROSS THE HIGH PLAINS FOR WEDNESDAY...BRINGING WARM CONDITIONS AND DRY WEATHER TO THE TRI STATE AREA. RELATIVE HUMIDITIES WILL LIKELY BE AT A CRITICAL LEVEL...HOWEVER CALM WIND SPEEDS UNDER A SURFACE HIGH PRESSURE SYSTEM IN THE SOUTHERN PLAINS WILL PROBABLY THWART ANY CRITICAL FIRE WEATHER CONDITIONS. THE UPPER LEVEL RIDGE WILL BEGIN TO BREAK DOWN TO ZONAL FLOW ALOFT FOR THURSDAY. A WEAK SURFACE FRONT WILL PASS THROUGH THE HIGH PLAINS THURSDAY...BUT VERY DRY MODEL SOUNDINGS INDICATE A PROFILE THAT IS UNLIKELY TO RESULT IN ANY PRECIP. MOST MODELS INDICATE A SHORTWAVE RIDGE WILL BUILD INTO THE HIGH PLAINS FOR FRIDAY...KEEPING CONDITIONS WARM AND DRY. MODELS INDICATE A CLOSED LOW SYSTEM WILL MOVE INTO THE FORECAST AREA BEGINNING SATURDAY...BRINGING POCKETS OF POSITIVE VORTICITY AND LIFT TO THE HIGH PLAINS. THIS SYSTEM WILL BRING CHANCES FOR PRECIPITATION NEXT WEEKEND WITH CHANCES OF SHOWERS AND THUNDERSTORMS. MODEL SOUNDINGS INDICATE SOME INSTABILITY WILL EXIST ACROSS THE AREA FOR SATURDAY...BUT STRONGER THUNDERSTORMS SHOULD STAY TO THE EAST OF THE FORECAST AREA. COLDER AIR WILL FILL INTO THE AREA BEHIND THE SURFACE COLD FRONT SATURDAY NIGHT...WHICH COULD BRING SOME SNOWFLAKES TO SOME NORTHWEST PORTIONS OF THE FORECAST AREA. PER COLLABORATION HOWEVER...LEFT RAIN SHOWERS IN THE FORECAST. EVEN IF SOME SNOW DID OCCUR...WARM SOIL TEMPERATURES WOULD NOT ALLOW ANY ACCUMULATION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1134 AM MDT SUN APR 6 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. ISOLATED TO POSSIBLY SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS THE AREA THIS AFTERNOON AND CONTINUE INTO EARLY THIS EVENING. DID CHOOSE TO PUT -TSRA AT BOTH SITES BUT IT DOES LOOK LIKE KMCK WILL HAVE THE BEST CHANCE AND THAT IS WHY I PUT IN A MINOR VISIBILITY RESTRICTION. LATER ON TONIGHT...A SURFACE TROUGH FOLLOWED BY A STRONG COLD FRONT WILL PUSH THROUGH THE AREA. NORTH TO NORTHWEST WINDS WILL BE SUSTAINED NEAR 25 KNOTS WITH GUSTS TO NEAR 35 KNOTS FROM NEAR 12Z TO THE END OF THE PERIOD. THESE GUSTY WINDS WILL LAST BEYOND THIS PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...RRH LONG TERM...MK AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1033 AM MDT SUN APR 6 2014 .UPDATE... ISSUED AT 1022 AM MDT SUN APR 6 2014 MODELS PLAYING CATCHUP THIS MORNING. SYSTEM THAT WAS EXPECTED TO BRING RAIN TO THE AREA LAST NIGHT INTO THIS MORNING IS MUCH FURTHER SOUTH THAN ANTICIPATED BY MYSELF AND MODEL OUTPUT. MAIN CHANCE FOR RAINFALL IS SOUTH OF MY AREA WITH A LITTLE BIT OF A CHANCE IN MY FAR SOUTHERN LOCATIONS FOR THE REST OF THIS MORNING. BECAUSE OF THE FURTHER SOUTH SOLUTION THERE IS A LOT LESS CLOUD COVER THAN THE MODELS THOUGHT THERE WOULD BE WHICH WILL ALLOW THE TEMPERATURES TO GET WARMER THAN EXPECTED. RAP WAS DOING A DECENT JOB WITH THIS AND USED FOR THE UPDATE. ALSO DRAMATICALLY REDUCED SKY COVER PER LATEST SATELLITE WITH MODEL OUTPUT HAVING TOO MUCH. SATELLITE AND PV ANALYSIS INDICATE A FAIRLY STRONG SHORTWAVE TROUGH MOVING TOWARD THE AREA FROM THE NORTHWEST. UPSTREAM 12Z SOUNDINGS DO SHOW SOME CAPE IN THIS AIR MASS. ALL MODEL OUTPUT IS SHOWING NEGATIVE THETA-E LAPSE RATES THROUGH MID LEVELS INTO THIS EVENING IN ADDITION TO KEEPING AROUND SURFACE AND ELEVATED CAPE. ALSO A SURFACE TROUGH IS PUSHING THE AREA AND IS ABOUT HALF WAY THROUGH THE AREA AT THIS TIME. SMALL SCALE OUTPUT IS INDICATING THAT THIS BOUNDARY WILL END UP BEING DRAPED OVER SOUTHERN AND EASTERN AREAS BY LATE THIS MORNING. SMALL SCALE OUTPUT IS ALSO GENERATING CONVECTIVE PRECIPITATION. SO ADJUSTED POPS THIS AFTERNOON AND EVENING ACCOUNTING FOR THE ABOVE MENTIONED PARAMETERS. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 303 AM MDT SUN APR 6 2014 AS OF 4 AM CDT...3 AM MDT...SKIES ACROSS THE TRI-STATE AREA WERE MOSTLY CLOUDY. TEMPERATURES HAVE BEEN SLOW TO FALL TONIGHT...COOLING INTO THE UPPER 30S TO MID 40S FOR MOST LOCATIONS. WINDS WERE FROM THE SOUTH AT 10 TO 20 MPH. A DEEP LONGWAVE TROUGH WAS LOCATED OVER THE FOUR CORNERS REGION WITH A SHORTWAVE TROUGH MOVING THROUGH WYOMING AND UTAH. A WEAK SURFACE LOW PRESSURE WAS LOCATED OVER WESTERN NEBRASKA. FOR TODAY...MAIN CONCERNS WITH THE FORECAST ARE THE CHANCES FOR PRECIPITATION AND POSSIBLE THUNDERSTORMS. SHOWERS HAVE DEVELOPED THIS MORNING ALONG A WEAK ELEVATED FRONTAL BAND THAT STRETCHES FROM NEAR PUEBLO...COLORADO TO HAYS...KANSAS. THIS TREND SHOULD CONTINUE THROUGH THE MORNING HOURS. ACTIVITY SO FAR HAS NOT BEEN IMPRESSIVE DUE TO A MORE STABLE ATMOSPHERE THAN PREVIOUSLY EXPECTED SO LOWERED POPS AND QPF FOR THIS MORNING. LATER TODAY...THE SHORTWAVE TROUGH MOVES THROUGH. WITH WARMER TEMPERATURES AND SOME WEAK INSTABILITY... EXPECTING A ROUND OF SHOWERS WITH ISOLATED THUNDERSTORMS TO DEVELOP OVER NORTHEAST COLORADO AND HEAD EAST. OVERALL...CAPE...SHEAR AND LAPSE RATES ARE MEAGER AT BEST. CONSIDERED REMOVING THE MENTION OF ISOLATED THUNDERSTORMS BUT DECIDED TO LEAVE IT IN AS A RUMBLE OF THUNDER OR TWO CAN NOT BE RULED OUT. WITH DENSE CLOUD COVER EXPECTED TODAY...THINK THAT INSTABILITY WILL BE LIMITED SO WIDESPREAD STORMS ARE NOT EXPECTED. FOR TONIGHT...A COLD FRONT PASSES THROUGH. BEHIND THIS FRONT...WINDY CONDITIONS CAN BE EXPECTED THROUGH MONDAY EVENING. MODELS SEEM TO HAVE COME DOWN ON THE POTENTIAL FOR STRONGER GUSTS AS THE WIND FIELD ALOFT IS WEAKER THAN IN PREVIOUS RUNS. HAVE NUDGED WINDS DOWN A COUPLE KNOTS BUT AM STILL FLIRTING WITH WIND ADVISORY CRITERIA. WILL NOT ISSUE A WIND ADVISORY WITH THIS FORECAST RUN AND ONE MAY NOT BE NEEDED AT ALL BASED ON THE LATEST MODEL TRENDS. SO FAR...THE LACK OF PRECIPITATION WOULD MEAN AN INCREASED THREAT OF BLOWING DUST. HOWEVER...WITH WEAKER WINDS EXPECTED...BLOWING DUST WOULD NOT BE A MAJOR THREAT FOR OUR REGION. AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS OVER THE ROCKIES ON MONDAY NIGHT...BRINGING QUIET WEATHER BACK TO THE TRI-STATE AREA. WARMER WEATHER IS ANTICIPATED TO RETURN WITH WARMER 850 MB TEMPS ADVECTING IN FROM THE SOUTHWEST. RELATIVE HUMIDITY VALUES DROP INTO THE 20 TO 25 PERCENT RANGE DUE TO DRY AIR IN PLACE AND WARMER WEATHER ON TUESDAY. HOWEVER...LIGHT WINDS WILL MITIGATE ANY THREAT OF CRITICAL FIRE WEATHER CONDITIONS BEING MET. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 224 AM MDT SUN APR 6 2014 UPPER LEVEL RIDGE WILL MAINTAIN DOMINANCE OF THE WEATHER ACROSS THE HIGH PLAINS FOR WEDNESDAY...BRINGING WARM CONDITIONS AND DRY WEATHER TO THE TRI STATE AREA. RELATIVE HUMIDITIES WILL LIKELY BE AT A CRITICAL LEVEL...HOWEVER CALM WIND SPEEDS UNDER A SURFACE HIGH PRESSURE SYSTEM IN THE SOUTHERN PLAINS WILL PROBABLY THWART ANY CRITICAL FIRE WEATHER CONDITIONS. THE UPPER LEVEL RIDGE WILL BEGIN TO BREAK DOWN TO ZONAL FLOW ALOFT FOR THURSDAY. A WEAK SURFACE FRONT WILL PASS THROUGH THE HIGH PLAINS THURSDAY...BUT VERY DRY MODEL SOUNDINGS INDICATE A PROFILE THAT IS UNLIKELY TO RESULT IN ANY PRECIP. MOST MODELS INDICATE A SHORTWAVE RIDGE WILL BUILD INTO THE HIGH PLAINS FOR FRIDAY...KEEPING CONDITIONS WARM AND DRY. MODELS INDICATE A CLOSED LOW SYSTEM WILL MOVE INTO THE FORECAST AREA BEGINNING SATURDAY...BRINGING POCKETS OF POSITIVE VORTICITY AND LIFT TO THE HIGH PLAINS. THIS SYSTEM WILL BRING CHANCES FOR PRECIPITATION NEXT WEEKEND WITH CHANCES OF SHOWERS AND THUNDERSTORMS. MODEL SOUNDINGS INDICATE SOME INSTABILITY WILL EXIST ACROSS THE AREA FOR SATURDAY...BUT STRONGER THUNDERSTORMS SHOULD STAY TO THE EAST OF THE FORECAST AREA. COLDER AIR WILL FILL INTO THE AREA BEHIND THE SURFACE COLD FRONT SATURDAY NIGHT...WHICH COULD BRING SOME SNOWFLAKES TO SOME NORTHWEST PORTIONS OF THE FORECAST AREA. PER COLLABORATION HOWEVER...LEFT RAIN SHOWERS IN THE FORECAST. EVEN IF SOME SNOW DID OCCUR...WARM SOIL TEMPERATURES WOULD NOT ALLOW ANY ACCUMULATION. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 534 AM MDT SUN APR 6 2014 AN UPPER LEVEL DISTURBANCE CONTINUES TO MOVE THROUGH. SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON BUT EXACT TIMING/PLACEMENT WAS UNKNOWN. MENTIONED VCTS FOR KMCK AS BOTH GFS AND NAM CROSS-SECTIONS DEPICT STRONGER LIFT AS THE MAIN SHORTWAVE TROUGH PASSES. THERE IS LOW CONFIDENCE IN THE PRECIP FORECAST AS WELL AS CIG HEIGHTS. EXPECTING VFR CONDITIONS FOR MAJORITY OF TAF PERIOD BUT CAN NOT RULE OUT BRIEF MVFR CONDITIONS UNDER A SHOWER OR STRATUS AS WAS OBSERVED AT KMCK EARLIER. SOUTHWEST WINDS WILL GIVE WAY TO NORTH WINDS BY THIS AFTERNOON. A COLD FRONT WITH GUSTY NORTHWEST WINDS IS EXPECTED TO MOVE THROUGH EARLY TOMORROW MORNING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...RRH LONG TERM...MK AVIATION...RRH
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
224 PM CDT SUN APR 6 2014 .UPDATE... UPDATE TO CANCEL SEVERE THUNDERSTORM WATCH 63 FOR OUR LOUISIANA PARISHES AND EXTEND OVER OUR SOUTHEAST TEXAS COUNTIES THROUGH 6 PM. CONVECTION HAS BEEN SLOW TO GET GOING ACRS OUR AREA SO FAR TODAY. HOWEVER...SEVERAL STRONG TO SEVERE STORMS HAVE BEEN DEVELOPING JUST TO THE WEST AND NORTH. LATEST HRRR AND RUC13 SHOW CONVECTION DEVELOPING AND MOVING INTO OUR WESTERN CWA...AND THIS IS SUPPORTED BY LATEST RADAR TRENDS SO OPTED TO EXTEND THE CURRENT SVR WATCH IN TIME. OTHERWISE...JUST MINOR TWEAKS TO POPS/WX AS WELL AS TEMPS AS WARM FRONT CURRENTLY SITS ALONG OR JUST NORTH OF A KBPT-KARA LINE AND SHOULD BE SLIDING NORTH OF KLCH WITHIN THE NEXT HOUR. 24 && .PREV DISCUSSION... /ISSUED 1240 PM CDT SUN APR 6 2014/ AVIATION...MAIN ISSUES IN THE VERY NEAR TERM WILL BE THE CONTINUATION OF IFR/LIFR NORTH OF THE WARM FRONT THAT IS NOW BEGINNING TO WORK INLAND ALONG THE COAST. THEN IT BECOMES SOMEWHAT DIFFICULT TO PIN DOWN THE TIMING OF TSRA...ESPECIALLY ALONG THE COASTAL SITES. AT THIS TIME THE BEST LIFT AND FORCING SEEMS TO BE BETWEEN 23Z AND 06Z THIS AFTERNOON AND TONIGHT. HAVE TRIED TO NARROW DOWN THE TIMING AS BEST WE CAN USING THE HIGH-RES GUIDANCE WHICH IS A BLEND OF THE HRRR AND THE NMC HIRES-ARW. WINDS WILL ALSO BE GUST FOR A TIME AT LFT AND ARA AS THE WARM SECTOR SURGE DEVELOPS IN A FEW HOURS. BRAZZELL PREV DISCUSSION... /ISSUED 1122 AM CDT SUN APR 6 2014/ UPDATE... STILL ANTICIPATE A BUSY DAY TODAY AS A VIGOROUS UPPER TROF ENTERS THE SRN PLAINS...INDUCING A SFC LOW NR THE TX COAST ON A WARM FRONTAL BOUNDARY THAT CURRENTLY SITS ALONG THE LA/TX COASTLINE. SVR WATCH 63 REMAINS IN EFFECT FOR MUCH OF THE AREA NORTH OF I-10...ALTHOUGH REGIONAL RADAR MOSAIC SHOWS MOST OF THE ACTIVITY CURRENTLY ACRS NRN LA INTO CNTL TX WITH JUST A FEW SHOWERS ACRS OUR CWA. WENT AHEAD AND ADJUSTED POPS FOR TODAY...BROKEN DOWN INTO SHORTER TIME INCREMENTS TO INDICATE A GRADUAL INCREASE THROUGH THE AFTN INTO THIS EVENING. ALSO ADDED FOG MAINLY TO SRN ZONES...WITH AREAS OF DENSE FOG OVER THE NEARSHORE WATERS AND COASTAL LAKES AND BAYS FOR THIS MORNING IN ASSOCIATION WITH THE WARM FRONT AS IT MOVES SLOWLY NORTH THROUGH EARLY AFTN. DEVELOPMENT AND EXPECTED TRACK OF THE SFC LOW ON THE WRN EDGE OF THE CWA...IN CONJUNCTION WITH THE APPROACH OF THE UPPER TROF...WILL YIELD AN ENVIRONMENT CONDUCIVE FOR SEVERE STORMS DURING THE AFTN AND EVENING WITH ALL TYPES OF SEVERE MODES POSSIBLE (TORNADOES...LARGE HAIL AND STRONG WINDS). ABUNDANT MOISTURE WILL ALSO BE IN PLACE WITH PRECIP WATER VALUES CLIMBING TO MORE THAN 1.7 INCHES...RESULTING IN THE POTENTIAL FOR HEAVY RAINFALL WITH THE STORMS. THUS...A FLOOD WATCH REMAINS IN EFFECT THROUGH TONIGHT. THE SEVERE/HEAVY RAIN THREAT WILL TRANSITION EAST OVERNIGHT TOWARD OUR S CNTL LA PARISHES...ENDING WITH THE PASSAGE OF THE COLD FRONT BY EARLY MONDAY MORNING. 24 PREV DISCUSSION... /ISSUED 733 AM CDT SUN APR 6 2014/ AVIATION UPDATE...REGARDING 12Z TAF ISSUANCE. HAVE INCLUDED LOW LEVEL WIND SHEAR AT ALL TERMINALS THIS MORNING. SURFACE ANALYSIS DEPICTING A WARM FRONTAL BOUNDARY JUST OFF THE COAST THIS MORNING AND ADVANCING NORTHWARD. SURFACE WINDS ARE CURRENTLY LIGHT EASTERLY BUT RAPIDLY VEER TO THE SOUTH AND INCREASE TO 30 KNOTS AT 2K FT. OTHERWISE...IFR CEILINGS WILL PREVAIL TODAY WITH INCREASING SHOWER AND THUNDERSTORM ACTIVITY EXPECTED. THIS AS A VIGOROUS LOW PRESSURE TROF ALOFT ADVANCES ACROSS THE SOUTH PLAINS SENDING THE AFOREMENTIONED FRONTAL BOUNDARY NORTH ACROSS THE AREA WHILE INDUCING SURFACE LOW PRESSURE ALONG THE BOUNDARY. ELEVATED BUT STILL POSSIBLE STRONG TO SEVERE THUNDERSTORMS WILL BE ON THE DOCKET THIS MORNING...BECOMING SURFACE BASED WITH THE SEVERE THREAT INCREASING THROUGH THE AFTERNOON AND EVENING AS THE AREA WARM SECTORS WITH THE NORTHWARD PASSAGE OF THE FRONT. MARCOTTE PREV DISCUSSION... /ISSUED 643 AM CDT SUN APR 6 2014/ DISCUSSION... SEVERE THUNDERSTORM WATCH 63 IS IN EFFECT FOR ALL COUNTIES AND PARISHES ALONG THE I-10 CORRIDOR NORTHWARD THIS MORNING. THE WATCH WILL GO UNTIL 2 PM TODAY. PREV DISCUSSION... /ISSUED 537 AM CDT SUN APR 6 2014/ DISCUSSION... RAINS/SHOWERS EXTEND FROM CENTRAL TEXAS INCLUDING THE COASTAL WATERS EAST INTO LOUISIANA... MISSISSIPPI... AND ARKANSAS. THIS ACTIVITY IS BEING DRIVEN FROM A DEVELOPING SURFACE LOW OVER THE SOUTH TEXAS COAST WITH A TRAILING WARM FRONT EXTENDING INTO THE LOUISIANA COASTAL WATERS. UPPER LEVEL SUPPORT IS COMING FROM A TROF BACK TO THE NORTHWEST. TEMPERATURES AROUND THE REGION ARE RUNNING IN THE LOW TO MID 50S. TODAY WE ARE LOOKING AT SHOWERS AND THUNDERSTORMS... WITH THE THREAT THAT A FEW STORMS MAY BECOME SEVERE AS THE WARM FRONT LIFTS NORTHWARD INTO LOUISIANA AND SOUTHEAST TEXAS. THE MAIN THREAT WILL BE FROM WINDS AND HAIL ALTHOUGH A TORNADO COULD NOT BE RULED OUT. ALSO THIS WILL ALLOW TEMPS TO CLIMB INTO THE 70S IN THE WARM SECTOR DURING THE AFTERNOON HOURS. IN ADDITION... RAINS WILL BE HEAVY AT TIMES AND A FLOOD WATCH HAS BEEN POSTED TODAY. THE FLOOD WATCH WILL CONTINUE INTO TOMORROW MORNING BEFORE ENDING AROUND SUNRISE. WE WILL REMAIN IN THE WARM SECTOR TONIGHT INTO EARLY MONDAY MORNING UNTIL THE NEXT COLD FRONT FINALLY PUSHES THIS MESS OFF TO THE EAST AND THE SURFACE LOW INTO CENTRAL MISSISSIPPI. RAINS FINALLY ENDING OVER SOUTH CENTRAL LOUISIANA MONDAY AFTERNOON. THEN COOL DRY WEATHER BECOMES ESTABLISHED THROUGH THE REST OF THE WEEK. THE DOWNSIDE IS RAINS MOVE BACK INTO THE FORECAST NEXT WEEKEND. 19 && .PRELIMINARY POINT TEMPS/POPS... KLCH 73 60 72 53 / 80 80 20 10 KBPT 74 60 73 56 / 80 70 20 10 KAEX 70 59 69 50 / 90 90 20 20 KLFT 76 66 73 55 / 70 90 20 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLOOD WATCH THROUGH MONDAY MORNING FOR ACADIA-ALLEN-AVOYELLES- BEAUREGARD-CALCASIEU-EAST CAMERON-EVANGELINE-IBERIA- JEFFERSON DAVIS-LAFAYETTE-LOWER ST. MARTIN-RAPIDES-ST. LANDRY-ST. MARY-UPPER ST. MARTIN-VERMILION-VERNON-WEST CAMERON. TX...FLOOD WATCH THROUGH MONDAY MORNING FOR HARDIN-JEFFERSON-NORTHERN JASPER-NORTHERN NEWTON-ORANGE-SOUTHERN JASPER-SOUTHERN NEWTON-TYLER. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1240 PM CDT SUN APR 6 2014 .AVIATION...MAIN ISSUES IN THE VERY NEAR TERM WILL BE THE CONTINUATION OF IFR/LIFR NORTH OF THE WARM FRONT THAT IS NOW BEGINNING TO WORK INLAND ALONG THE COAST. THEN IT BECOMES SOMEWHAT DIFFICULT TO PIN DOWN THE TIMING OF TSRA...ESPECIALLY ALONG THE COASTAL SITES. AT THIS TIME THE BEST LIFT AND FORCING SEEMS TO BE BETWEEN 23Z AND 06Z THIS AFTERNOON AND TONIGHT. HAVE TRIED TO NARROW DOWN THE TIMING AS BEST WE CAN USING THE HIGH-RES GUIDANCE WHICH IS A BLEND OF THE HRRR AND THE NMC HIRES-ARW. WINDS WILL ALSO BE GUST FOR A TIME AT LFT AND ARA AS THE WARM SECTOR SURGE DEVELOPS IN A FEW HOURS. BRAZZELL && .PREV DISCUSSION... /ISSUED 1122 AM CDT SUN APR 6 2014/ UPDATE... STILL ANTICIPATE A BUSY DAY TODAY AS A VIGOROUS UPPER TROF ENTERS THE SRN PLAINS...INDUCING A SFC LOW NR THE TX COAST ON A WARM FRONTAL BOUNDARY THAT CURRENTLY SITS ALONG THE LA/TX COASTLINE. SVR WATCH 63 REMAINS IN EFFECT FOR MUCH OF THE AREA NORTH OF I-10...ALTHOUGH REGIONAL RADAR MOSAIC SHOWS MOST OF THE ACTIVITY CURRENTLY ACRS NRN LA INTO CNTL TX WITH JUST A FEW SHOWERS ACRS OUR CWA. WENT AHEAD AND ADJUSTED POPS FOR TODAY...BROKEN DOWN INTO SHORTER TIME INCREMENTS TO INDICATE A GRADUAL INCREASE THROUGH THE AFTN INTO THIS EVENING. ALSO ADDED FOG MAINLY TO SRN ZONES...WITH AREAS OF DENSE FOG OVER THE NEARSHORE WATERS AND COASTAL LAKES AND BAYS FOR THIS MORNING IN ASSOCIATION WITH THE WARM FRONT AS IT MOVES SLOWLY NORTH THROUGH EARLY AFTN. DEVELOPMENT AND EXPECTED TRACK OF THE SFC LOW ON THE WRN EDGE OF THE CWA...IN CONJUNCTION WITH THE APPROACH OF THE UPPER TROF...WILL YIELD AN ENVIRONMENT CONDUCIVE FOR SEVERE STORMS DURING THE AFTN AND EVENING WITH ALL TYPES OF SEVERE MODES POSSIBLE (TORNADOES...LARGE HAIL AND STRONG WINDS). ABUNDANT MOISTURE WILL ALSO BE IN PLACE WITH PRECIP WATER VALUES CLIMBING TO MORE THAN 1.7 INCHES...RESULTING IN THE POTENTIAL FOR HEAVY RAINFALL WITH THE STORMS. THUS...A FLOOD WATCH REMAINS IN EFFECT THROUGH TONIGHT. THE SEVERE/HEAVY RAIN THREAT WILL TRANSITION EAST OVERNIGHT TOWARD OUR S CNTL LA PARISHES...ENDING WITH THE PASSAGE OF THE COLD FRONT BY EARLY MONDAY MORNING. 24 PREV DISCUSSION... /ISSUED 733 AM CDT SUN APR 6 2014/ AVIATION UPDATE...REGARDING 12Z TAF ISSUANCE. HAVE INCLUDED LOW LEVEL WIND SHEAR AT ALL TERMINALS THIS MORNING. SURFACE ANALYSIS DEPICTING A WARM FRONTAL BOUNDARY JUST OFF THE COAST THIS MORNING AND ADVANCING NORTHWARD. SURFACE WINDS ARE CURRENTLY LIGHT EASTERLY BUT RAPIDLY VEER TO THE SOUTH AND INCREASE TO 30 KNOTS AT 2K FT. OTHERWISE...IFR CEILINGS WILL PREVAIL TODAY WITH INCREASING SHOWER AND THUNDERSTORM ACTIVITY EXPECTED. THIS AS A VIGOROUS LOW PRESSURE TROF ALOFT ADVANCES ACROSS THE SOUTH PLAINS SENDING THE AFOREMENTIONED FRONTAL BOUNDARY NORTH ACROSS THE AREA WHILE INDUCING SURFACE LOW PRESSURE ALONG THE BOUNDARY. ELEVATED BUT STILL POSSIBLE STRONG TO SEVERE THUNDERSTORMS WILL BE ON THE DOCKET THIS MORNING...BECOMING SURFACE BASED WITH THE SEVERE THREAT INCREASING THROUGH THE AFTERNOON AND EVENING AS THE AREA WARM SECTORS WITH THE NORTHWARD PASSAGE OF THE FRONT. MARCOTTE PREV DISCUSSION... /ISSUED 643 AM CDT SUN APR 6 2014/ DISCUSSION... SEVERE THUNDERSTORM WATCH 63 IS IN EFFECT FOR ALL COUNTIES AND PARISHES ALONG THE I-10 CORRIDOR NORTHWARD THIS MORNING. THE WATCH WILL GO UNTIL 2 PM TODAY. PREV DISCUSSION... /ISSUED 537 AM CDT SUN APR 6 2014/ DISCUSSION... RAINS/SHOWERS EXTEND FROM CENTRAL TEXAS INCLUDING THE COASTAL WATERS EAST INTO LOUISIANA... MISSISSIPPI... AND ARKANSAS. THIS ACTIVITY IS BEING DRIVEN FROM A DEVELOPING SURFACE LOW OVER THE SOUTH TEXAS COAST WITH A TRAILING WARM FRONT EXTENDING INTO THE LOUISIANA COASTAL WATERS. UPPER LEVEL SUPPORT IS COMING FROM A TROF BACK TO THE NORTHWEST. TEMPERATURES AROUND THE REGION ARE RUNNING IN THE LOW TO MID 50S. TODAY WE ARE LOOKING AT SHOWERS AND THUNDERSTORMS... WITH THE THREAT THAT A FEW STORMS MAY BECOME SEVERE AS THE WARM FRONT LIFTS NORTHWARD INTO LOUISIANA AND SOUTHEAST TEXAS. THE MAIN THREAT WILL BE FROM WINDS AND HAIL ALTHOUGH A TORNADO COULD NOT BE RULED OUT. ALSO THIS WILL ALLOW TEMPS TO CLIMB INTO THE 70S IN THE WARM SECTOR DURING THE AFTERNOON HOURS. IN ADDITION... RAINS WILL BE HEAVY AT TIMES AND A FLOOD WATCH HAS BEEN POSTED TODAY. THE FLOOD WATCH WILL CONTINUE INTO TOMORROW MORNING BEFORE ENDING AROUND SUNRISE. WE WILL REMAIN IN THE WARM SECTOR TONIGHT INTO EARLY MONDAY MORNING UNTIL THE NEXT COLD FRONT FINALLY PUSHES THIS MESS OFF TO THE EAST AND THE SURFACE LOW INTO CENTRAL MISSISSIPPI. RAINS FINALLY ENDING OVER SOUTH CENTRAL LOUISIANA MONDAY AFTERNOON. THEN COOL DRY WEATHER BECOMES ESTABLISHED THROUGH THE REST OF THE WEEK. THE DOWNSIDE IS RAINS MOVE BACK INTO THE FORECAST NEXT WEEKEND. 19 && .PRELIMINARY POINT TEMPS/POPS... KLCH 77 60 73 54 71 / 80 90 20 10 10 KBPT 76 60 73 56 73 / 80 70 20 10 10 KAEX 71 59 69 50 69 / 90 90 20 20 10 KLFT 78 66 73 55 70 / 70 90 20 10 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...FLOOD WATCH THROUGH MONDAY MORNING FOR THE FOLLOWING ZONES: ACADIA...ALLEN...AVOYELLES...BEAUREGARD...CALCASIEU...EAST CAMERON...EVANGELINE...IBERIA...JEFFERSON DAVIS... LAFAYETTE...LOWER ST. MARTIN...RAPIDES...ST. LANDRY...ST. MARY...UPPER ST. MARTIN...VERMILION...VERNON...WEST CAMERON. TX...FLOOD WATCH THROUGH MONDAY MORNING FOR THE FOLLOWING ZONES: HARDIN...JEFFERSON...NORTHERN JASPER...NORTHERN NEWTON... ORANGE...SOUTHERN JASPER...SOUTHERN NEWTON...TYLER. GM...DENSE FOG ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR THE FOLLOWING ZONES: CALCASIEU LAKE...COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM...COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM...SABINE LAKE...VERMILION BAY. && FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.LAKECHARLES.GOV WWW.TWITTER.COM/NWSLAKECHARLES WWW.YOUTUBE.COM/NWSLAKECHARLES && $$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
954 PM EDT MON APR 7 2014 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE REGION OVERNIGHT. A COLD FRONT WILL CROSS THE AREA LATER TONIGHT AND EXIT THE COAST TUESDAY MORNING. THE FRONT STALLS ALONG THE CAROLINAS ON TUESDAY AS A WEAK TROUGH OF LOW PRESSURE DEVELOPS ALONG THIS BOUNDARY AND LINGERS NEAR THE COAST THROUGH TUESDAY NIGHT. HIGH PRESSURE BUILDS BACK INTO THE MID ATLANTIC STATES ON WEDNESDAY AND MOVES OVERHEAD ON THURSDAY. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... A WARM FRONT WAS LIFTING INTO N/CNTRL VA...SRN MD AND DE LATE MON EVENG. LO PRES WAS LOCATED OVR CNTRL OHIO...WITH A COLD FRONT EXTENDING FM THE LO SWRD THRU EXTRM ERN KY AND TN. LATEST RADAR INDICATED SHOWERS MOVNG NNE THRU ERN SC AND NC. BASED ON THE LATEST HRRR DERIVED REFLECTIVITY FCST AND THE FACT OF THE COLD FRONT PUSHING EWRD INTO/ACRS THE FA...SHOWER ACTIVITY WILL RE- GENERATE AND SPREAD NNE UP THRU MAINLY CNTRL/ERN PORTIONS OF THE REGION. WILL MAINTAIN A SLGT CHC FOR THUNDER OVR SE VA AND NE NC CNTIES...WHERE HIGHER DWPTS/BETTER INSTABILITY WILL REMAIN. MIN TEMPS WILL RANGE FM THE MID TO UPR 40S EXTRM W/NW TO THE LWR 60S SE. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... THE COLD FRONT EXITS THE COAST TUE MORNING...THEN STALLS ALONG THE CAROLINAS DURING THE DAY. EXPECT LINGERING SHOWERS ALONG THE MID ATLANTIC COAST IN THE MORNING WITH PRECIP TAPERING OFF AND BECOMING CONFINED OVER NE NC/FAR SE VA DURING THE AFTN . A WEAK TROUGH OF LOW PRESSURE DEVELOPS JUST OFF THE CAROLINA COAST TUE NIGHT (ALONG THE STALLED FRONTAL BOUNDARY). THE WEAK TROUGH WILL BE SUPPORTED BY UPPER LEVEL SHORTWAVE/JET STREAK ENERGY TO ENHANCE PRECIPITATION AFTER MIDNIGHT TUE NIGHT...HOWEVER THE BEST DYNAMICS WILL BE LOCATED SOUTH OF THE FA. TO ERR ON THE SIDE OF CAUTION... HAVE CARRIED A SLIGHT CHANCE FOR LIGHT RAIN SHOWERS ALONG ALBEMARLE SOUND DURING THIS TIME. PARTLY CLOUDY SKIES WILL YIELD OVERNIGHT LOWS IN THE 40S REGIONWIDE. HIGH PRESSURE BUILDS BACK INTO THE MID ATLANTIC STATES ON WEDNESDAY AS A VERY WEAK TROUGH PASSES NORTH OF THE AREA. THE TROUGH SHOULD ALLOW JUST ENOUGH COLD AIR TO FILTER INTO NRN COUNTIES. EXPECT HIGH IN THE LOW-MID 60S NORTH TO MID-UPPER 60S SOUTH UNDER PARTLY SUNNY SKIES. SKIES CLEAR WED NIGHT THUS PROMOTING RADIATIONAL COOLING...SO EXPECT LOW TEMPS IN THE UPPER 30S TO AROUND 40S FAR NW COUNTIES AND LOW-MID 40S ELSEWHERE. HIGH PRESSURE MOVES OVERHEAD ON THURSDAY. AS THE RIDGE AXIS SHIFTS EWD DURING THE DAY...EXPECT A NICE WARMING TREND UNDER MOSTLY SUNNY SKIES. HIGHS SHOULD PEAK IN THE LOWER 70S (MID-UPPER 60S IMMEDIATE COAST). && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... SEASONABLY WARM TEMPERATURES WILL HEADLINE THE EXTENDED PERIOD FORECAST WITH CHANCES OF SHOWERS EARLY NEXT WEEK. ZONAL FLOW ALOFT TO BEGIN THE EXTENDED AS A SHORTWAVE TRACKS ACROSS SE CANADA THURS NIGHT-FRI MORNING. THIS WILL PUSH A WEAK COLD FRONT TOWARD THE CTRL APPALACHIANS FRI. HIGH PRESSURE WILL CENTER OVER THE WRN ATLANTIC FRI...RIDGING SWWD INTO THE GULF STATES. HIGH PRESSURE AND WLY FLOW ALOFT WILL LIMIT ANY RETURN MOISTURE REGARDLESS OF SLY FLOW ON THE BACK SIDE OF THE SFC HIGH. THIS WILL KEEP THE LOCAL AREA DRY ON FRI. CYCLONIC FLOW WILL INCREASE OVER THE ERN CONUS FRI AS NRN STREAM ENERGY DIGS OVER THE MIDWEST. MODELS DEVELOP A WAVE ALONG THE FRONT OVER NRN VA/MD... WHICH MAY ENHANCE RAINFALL IN THAT REGION. WILL MAINTAIN SLIGHT CHANCE-LOW END CHANCE POPS OVER THE NRN LOCAL AREA...INCLUDING THE MD ERN SHORE FRI-FRI NIGHT. MODELS THEN DIFFER ON PUSHING THE WEAK FRONT THROUGH THE LOCAL AREA SAT. TRENDED TOWARD THE GFS...THINKING THE FRONT WILL HAVE TROUBLE PUSHING THROUGH THE REGION. ECMWF MORE ROBUST WITH SHORTWAVE TRAVERSING THE REGION FRI NIGHT-THURS MORNING...PUSHING THE FRONT THRU THE LOCAL AREA. REGARDLESS OF WHICH MODEL VERIFIES...LACK OF MOISTURE AND DYNAMICS...AS WELL AS SUBSIDENCE BEHIND THE FRONT WILL KEEP THE FORECAST DRY SAT. SUNDAY WILL ALSO BE DRY AS HIGH PRESSURE/SUBSIDENCE DOMINATES. MEANWHILE... A DEEPENING TROUGH OVER THE WRN CONUS/INTERMOUNTAIN WEST WILL AMPLIFY THE FLOW OVER THE ERN CONUS. AN ASSOCIATED COLD FRONT WILL PROPAGATE EWD OVER THE MIDWEST INTO THE OH VALLEY SUN NIGHT-MON MORNING. MEANINGFUL DIFFERENCES EXIST IN THE MODELS...WITH THE GFS 12+ HRS FASTER WITH THE FRONT/MOISTURE THAN ITS ECMWF COUNTERPART. HAVE OPTED FOR SLIGHT CHANCE-LOW END CHANCE POPS BEGINNING MON TO ACCOUNT FOR UNCERTAINTY. DAYTIME TEMPS WILL BE SEASONABLY WARM...GENERALLY IN THE LOW-MID 70S. SLIGHTLY COOLER SAT WITH FRONTAL PASSAGE AND NLY WINDS. SLY WINDS FRI AND SUN-MON WILL RESULT IN LOCALLY COOLER TEMPS ALONG THE COASTAL ERN SHORE. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... SFC LOW OVER THE OHIO VALLEY WILL TAKE OVER THE SURFACE WIND PATTERN OVERNIGHT ACROSS THE MID ATLANTIC STATES OVERNIGHT. A STRONG UPPER LEVEL JET MOVING THROUGH THE REGION BY EARLY MORNING WILL PROVIDE LIFT FOR PCPN TO REDEVELOP ACROSS THE TAF SITES OVERNIGHT. HAVE PCPN BEGIN BY MIDNIGHT AT MOST LOCATIONS. MOS FCSTS APPEAR PESSIMISTIC BUT STILL FORECAST IFR IN THE TAFS TO DEVELOP NEAR THE TIME OF THE PCPN AND CONTINUE INTO THE MORNING. SOUTH TO SOUTHWEST WINDS MAY BE GUSTY AT SOME LOCATIONS OVERNIGHT. WEST WINDS (A FEW GUSTS ARE AGAIN POSSIBLE) DEVELOP BEHIND A MORNING COLD FRONTAL PASSAGE AND CONDITIONS IMPROVE TO VFR TOWARD MIDDAY. OUTLOOK...HIGH PRESSURE BUILDS INTO THE REGION WITH MAINLY VFR AND DRY THE REST OF THE WEEK. && .MARINE... SFC LOW PRESSURE WILL LIFT OVER THE OH VALLEY THRU THIS EVENING WITH A TRAILING COLD FRONT APPROACHING THE WATERS FROM THE WEST. WARM FRONT CURRENTLY LOCATED OVER THE WATERS WILL CONTINUE TO LIFT TO THE NORTH...WITH FLOW BECOMING SLY OVER THE WATERS. WIDESPREAD SHOWERS WITH REDUCED VISIBILITIES WILL CONTINUE THIS EVENING. GRADIENT WILL STRENGTHEN IN ADVANCE OF THE FRONT WITH SLY WINDS INCREASING OVER THE WATERS. UNFAVORABLE LAPSE RATES (COLD WATERS AND WARM TEMPS ALOFT) WILL LIKELY LIMIT STRONGEST WINDS ALOFT FROM MIXING TO THE WATERS. HOWEVER...HEIGHT FALLS IN ADVANCE OF THE FRONT SHOULD BE ENOUGH TO COMPENSATE FOR THE LACK OF GOOD MIXING... ESPECIALLY THIS EVENING AND OVERNIGHT. WINDS WILL AVERAGE 15 TO 20 KT OVER THE BAY AND 20 TO 25 KT OVER THE COASTAL WATERS. POTENTIAL EMBEDDED CONVECTION IN WIDESPREAD SHOWERS COULD ALSO RESULT IN LOCALLY STRONG WINDS. SEAS WILL ALSO BUILD TO AN AVERAGE OF 5 TO 7 FT...BUT COULD BUILD AS HIGH AS 8-9 FT 20 NM OUT. AIR TEMPS NEAR WARMING WATER TEMPS COULD ALSO RESULT IN AREAS OF FOG OVERNIGHT. FRONT WILL CROSS THE WATERS EARLY TUES MORNING WITH WINDS BECOMING W-NW TUES AND N-NW TUES NIGHT. LACK OF CAA AND STRONG GRADIENT WINDS (HIGH PRESSURE BUILDING IN FROM THE SW) WILL PRODUCE SUB-SCA WINDS (AOB 15 KT IN THE BAY AND AOB 20 KT COASTAL WATERS) OVER THE WATERS TUES-TUES NIGHT. SEAS WILL BE SLOW TO SUBSIDE TUES... REMAINING 4-6 FT THRU TUES EVENING. EXTENDED THE SCA HEADLINES FOR ALL COASTAL ZONES THRU MIDNIGHT TUES NIGHT/WEDS MORNING. HIGH PRESSURE BUILDS OVER THE WATERS WEDS-THURS RESULTING IN SUB-SCA CONDITIONS. A WEAK COLD FRONT WILL APPROACH THE WATERS THURSDAY NIGHT-EARLY FRI MORNING...LIKELY STALLING OVER THE REGION FRI. && .TIDES/COASTAL FLOODING... GIVEN THE PROGRESSIVE MOVEMENT OF THE APPROACHING SYSTM...TIDES EXPECTED TO REMAIN BLO MINOR FLOODING THRESHOLDS DESPITE RUNNING ABT ONE FOOT ABOVE NORMAL. EXPECT TUES MORNING HIGH TIDE CYCLE TO BE THE HIGHEST ESPECIALLY ACROSS THE MIDDLE CHES BAY WHERE SOUTHERLY WINDS HAVE A HISTORY OF PILING UP THE WATER LONGER THAN GUID SUGGESTS. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ630>638. SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TUESDAY NIGHT FOR ANZ650-652-654-656-658. && $$ SYNOPSIS...BMD NEAR TERM...BMD/TMG SHORT TERM...BMD LONG TERM...SAM AVIATION...LSA MARINE...SAM TIDES/COASTAL FLOODING...AKQ
AREA FORECAST DISCUSSION
NWS DULUTH MN
1219 AM CDT SUN APR 6 2014 .UPDATE... ISSUED AT 936 PM CDT SAT APR 5 2014 THE NORTHLAND WILL BE UNDER GENERAL WAA WITH A COUPLE SHORTWAVES ALSO MOVING THROUGH THE AREA. RADAR WAS SHOWING TWO AREAS OF PRECIPITATION OVER THE NORTHLAND. THE FIRST STRETCHED FROM THE MOOSE LAKE AREA...SOUTHEAST TOWARD HAYWARD. THIS WAS LIGHT RAIN. ANOTHER AREA HAS RECENTLY DEVELOPED FROM BIG FORK EAST TO COOK/ORR TO ELY. THIS WILL ALSO LIKELY BE RAIN INITIALLY. PRECIP TYPE WILL BE AN ISSUE OVERNIGHT. FORECAST SOUNDINGS SHOW EITHER A WARM LAYER ENOUGH TO MELT ANY ICE OR A COLUMN NOT SATURATED ENOUGH FOR MUCH ICE. THE RAP MAX T OVER THE LOWEST SEVERAL THOUSAND FEET SHOWS MOST AREAS WILL SEE TEMPS AT OR ABOVE 2C. SURFACE TEMPS WILL BE THE MAIN FACTOR IN WHETHER LIGHT RAIN OR LIGHT FREEZING RAIN FALLS. WE DID EXPAND THE AREA THAT MAY SEE SOME LIGHT FREEZING RAIN TONIGHT TO INCLUDE MORE OF FAR NORTHERN MINNESOTA...AND A PORTION OF NORTHWEST WISCONSIN. KPBH WAS 34F OVER 25F AT 02Z. WE DO EXPECT ANY PRECIP TO BE RATHER LIGHT. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 322 PM CDT SAT APR 5 2014 SLY FLOW AHEAD OF H85 WEAK SHORT WAVE HAS ALLOWED TEMPS TO WARM WELL INTO THE 40S ACROSS MUCH OF THE FORECAST AREA. THE EXCEPTION IS ALONG THE NORTH SHORE OF LAKE SUPERIOR WHERE THE ONSHORE WINDS KEPT READINGS IN THE LOW/MIDDLE 30S. LATEST MODEL RUNS SHOW LOW AND MID LEVELS SATURATE QUICKLY THROUGH THE EVENING...AS THE SHORT WAVE MOVES INTO NW MINNESOTA. THIS WAVE IS RELATIVELY WEAK...BUT THERE IS SUFFICIENT WAA/ISENTROPIC LIFT AND MOISTURE TO SUPPORT LIGHT SHOWERS. HAVE BROAD BRUSH SMALL POPS FOR RAIN SHOWERS THIS EVENING AND OVERNIGHT...MAINLY AFTER 900 PM. HAVE ALSO INCLUDED AREAS FOG FOR ALL ZONES AFTER MIDNIGHT WITH DEW POINTS IN THE 30S AND CALM WINDS. MOST AREAS CAN EXPECT A BATCH OF -SHRA OR -DZ OVERNIGHT WITH RAINFALL AMOUNTS OF A TRACE TO A FEW HUNDREDTHS. LOCATIONS IN THE MN ARROWHEAD MAY SEE GREATER QPF...AROUND A TENTH OF AN INCH...AS WELL AS A SMALL THREAT FOR VERY LIGHT -FZDZ AFTER MIDNIGHT. NO ICE ACCUM IS ANTICIPATED ATTM. ELSEWHERE...SFC TEMPS ARE EXPECTED TO REMAIN WARM ENOUGH TO INHIBIT ANY -FZDZ...WITH COOLER READINGS ARRIVING IN THE DRIER AIR ON THE BACK SIDE OF THE WAVE AFTER THE PRECIP ENDS. THE LOW POPS AND DRIZZLE/LIGHT RAIN WILL LINGER OVER THE NRN WISCONSIN AND SOUTH SHORE OF LAKE SUPERIOR ZONES INTO SUNDAY AFTERNOON. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 322 PM CDT SAT APR 5 2014 WE ARE DEFINITELY ENTERING INTO THAT TIME OF YEAR WHERE WE START TO SEE A LOT OF FOG AND DRIZZLE ACROSS THE NORTHLAND. THIS WILL LIKELY BE THE CASE SUNDAY NIGHT INTO MONDAY AND PERHAPS BEYOND IN SOME OF THE TIME PERIODS THROUGHOUT THE EXTENDED TIME FRAME. THE MODELS ARE INDICATING A DECENT LIKELIHOOD OF LOWS CLOUDS...FOG AND DRIZZLE SUNDAY NIGHT AND MONDAY AND HAVE ADDED PATCHY FOG FOR NOW. WE WILL ALSO WRESTLE WITH THE MODELS HINTING AT SMALL QPF BULLSEYES RANDOMLY ACROSS THE REGION. WILL GENERALLY KEEP MOST PERIODS DRY FOR NOW. COULD SEE HAVING TO ADD SOME SMALL POPS AND PERHAPS SOME DRIZZLE AT SOME POINT...BUT FOR NOW NOT ENOUGH CONTINUITY BETWEEN THE MODEL RUNS AND AGREEMENT AMONGST THE MODELS TO HIT ANY PARTICULAR PRECIPITATION AREAS IN THE GRIDS. HAVE ADDED POPS TO MONDAY AFTERNOON. THE MODELS ARE HINTING AT SOME WEAK INSTABILITY DURING THE AFTERNOON...SO WE MAY SEE THE DEVELOPMENT OF A FEW SHOWERS IN THE VICINITY OF THE THERMAL TROUGH MOVING ACROSS THE CWA. TEMPERATURES ARE EXPECTED TO WARM CONSIDERABLY THROUGH MIDWEEK...WHICH WILL ALSO HELP TO BE ABLE TO HOLD MORE MOISTURE FROM THE SPRING SNOWMELT. HIGH TEMPERATURES BY MIDWEEK SHOULD BE LARGELY IN THE 50S ACROSS THE CWA. DEPENDING ON THE AMOUNT OF CLOUD COVER AND LOW CLOUDS/FOG...WE COULD SEE SOME READINGS A BIT HIGHER THAN THAT. IN FACT...THE ECMWF IS PEGGING A HIGH TEMP AROUND 70 FOR THE KBRD AREA ON WEDNESDAY AFTERNOON...AS THEY WILL BE IN THE WARM SECTOR AHEAD OF A COLD FRONT DROPPING SOUTHWARD BY WEDNESDAY NIGHT. COULD BE A DECENT SHOT OF RAIN SHOWERS WEDNESDAY EVENING AND OVERNIGHT...CHANGING TO SNOW POSSIBLY TOWARD THE NORTH. TEMPS SHOULD THEN COOL A BIT BEHIND THE FRONT...FOR THE END OF THE WEEK...WITH THE NEXT CHANCE OF PRECIPITATION ARRIVING FOR NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1218 AM CDT SUN APR 6 2014 CONFIDENCE REMAINS LOW REGARDING STRATUS/FOG DEVELOPMENT THROUGH THE PERIOD. LOW STRATUS/FOG HAD YET TO FORM AS OF 0430Z...BUT CEILINGS FROM 4500-6000FEET HAVE EXPANDED. A SHORTWAVE LIFTING NORTHEAST THROUGH THE AREA HAS AIDED IN THE DEVELOPMENT OF SHOWERS THIS EVENING...AND WE EXPECT THERE TO BE SOME LIGHT SHOWERS OVERNIGHT INTO SUNDAY MORNING. ANOTHER SHORTWAVE WILL MOVE ACROSS NORTHERN MINNESOTA TONIGHT AND MAY BRING A BETTER CHANCE FOR SOME LIGHT PRECIP THERE. SOME LOCATIONS MAY DROP BELOW FREEZING AND WE COULD SEE SOME PATCHY LIGHT FREEZING RAIN AS WELL. THE HRRR/RAP AND EVEN THE NAM HAVE BACKED OFF ON THE AMOUNT OF FOG/STRATUS TONIGHT. THE NAM/GFS STILL WANT TO DEVELOP LOW CEILINGS/VSBYS IN SPOTS SUNDAY AS THE LOW LEVEL FLOW WEAKENS FURTHER UNDER A STRONG INVERSION. WE BACKED OFF ON THE IFR/LIFR CONDITIONS TONIGHT AS CONFIDENCE JUST IS NOT THERE. WE ADDED SOME LLWS TO MOST OF THE TAF SITES INTO THE MORNING HOURS. && .PRELIMINARY POINT TEMPS/POPS... DLH 30 47 27 44 / 10 20 10 10 INL 29 46 25 44 / 10 20 10 10 BRD 32 51 30 49 / 10 20 10 10 HYR 30 49 27 46 / 10 20 10 10 ASX 29 46 27 43 / 10 10 10 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ UPDATE...MELDE SHORT TERM...GRANING LONG TERM...DAP AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1156 PM CDT SAT APR 5 2014 .SYNOPSIS... ISSUED AT 312 PM CDT SAT APR 5 2014 H5 ANALYSIS FROM THIS MORNING INDICATES A SPLIT FLOW REGIME ACROSS THE CONUS. IN THE NRN STREAM...ZONAL FLOW EXTENDED FROM THE PACIFIC NW COAST INTO THE GREAT LAKES. FURTHER EAST...A STRONG SHORTWAVE AND ASSOCIATED TROUGH EXTENDED FROM SRN QUEBEC INTO THE MID ATLANTIC STATES. IN THE SRN STREAM...A STRONG SHORTWAVE WAS LOCATED OVER SWRN ARIZONA WITH HT FALLS OF 50 TO 130 METERS NOTED FROM EL PASO TO TUSCON. AT THE SURFACE...A TROUGH OF LOW PRESSURE EXTENDED FROM SWRN SOUTH DAKOTA INTO THE NEBRASKA PANHANDLE AND EASTERN COLORADO. FURTHER EAST...HIGH PRESSURE WAS ANCHORED OVER NRN MISSOURI. DECENT SRLY WINDS HAVE DEVELOPED OVER CENTRAL AND EASTERN NEBRASKA THIS MORNING BETWEEN THE TROUGH IN THE WEST AND HIGH PRESSURE TO THE EAST. THE SRLY WINDS...ALLOWED FOR DECENT MIXING BY MID MORNING WHICH PUSHED TEMPS INTO THE UPPER 40S TO LOWER 50S. BY 2 PM CDT...UNDER MOSTLY CLEAR SKIES...TEMPERATURE RANGED FROM 57 AT NORTH PLATTE...TO 65 AT VALENTINE. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 312 PM CDT SAT APR 5 2014 A WEAK SURFACE TROUGH IS SAGGING SOUTH INTO NORTHERN NEBRASKA THIS AFTERNOON...AND WILL BE FOLLOWED BY A COLD FRONT SHORTLY BEHIND. A FEW SHOWERS/THUNDERSTORMS MAY INITIATE ALONG THE SURFACE TROUGH YET THIS AFTERNOON. HOWEVER...THE COVERAGE OF ANY ACTIVITY IS EXPECTED TO BE ISOLATED. THE BEST CHANCE FOR ACTIVITY EXTENDS FROM GARDEN COUNTY NORTHEAST TO SOUTHEAST CHERRY COUNTY AS INDICATED LATEST SURFACE ANALYSIS WHERE CAPES OF 100-250 J/KG EXIST. ALSO...THE LATEST NAM AND HRRR BOTH FAVOR SOME ACTIVITY IN THIS AREA. TONIGHT...THE NAM IS HINTING AT LOW CLOUDS OR FOG IN THE NORTH. BELIEVE THIS IS A BIT OVERDONE...BUT WORTH MONITORING. TOMORROW...AN UPPER LEVEL WAVE MOVES EAST ACROSS CO/KS...WHILE ANOTHER PIECE OF ENERGY MOVES ESE FROM WY INTO NE LATER IN THE DAY. PRECIPITATION CHANCES WILL BE ON THE INCREASE AS MODELS ARE GENERATING A FAIR AMOUNT OF LIFT IN THE WEST AHEAD OF THE WAVE. A WEAK SURFACE BOUNDARY WILL RUN FROM AROUND ONEILL TO IMPERIAL TOMORROW AS WELL. SHOWERS AND ISOLATED THUNDERSTORMS WILL BE POSSIBLE...WITH RATHER LOW CAPES OF ABOUT 100-200 J/KG. SOME MODELS ARE HINTING AT THE BEST ACTIVITY ALONG THE BOUNDARY LATE IN THE AFTERNOON. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 312 PM CDT SAT APR 5 2014 SUNDAY NIGHT THROUGH TUESDAY...THE MAIN FORECASTING CHALLENGES ARE PRECIPITATION CHANCES SUNDAY NIGHT AND MONDAY...ALONG WITH TEMPERATURES FOR SUNDAY NIGHT THROUGH TUESDAY. FOR SUNDAY NIGHT...A NORTHERN STREAM SHORTWAVE...WILL DIVE SOUTH ACROSS THE WESTERN DAKOTAS...APPROACHING NORTHERN NEBRASKA BY 12Z MONDAY. IN ADVANCE OF THIS FEATURE...ABUNDANT MID LEVEL LIFT WILL CARRY OVER FROM SUNDAY AFTERNOON ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. BOTH THE NAM AND GFS SOLNS HAVE NEGATIVE LI`S SUNDAY EVENING WITH UNSTABLE CONDS ACROSS THE ENTIRE FORECAST AREA. INHERITED FCST HAD A MENTION OF THUNDER SUNDAY EVENING...AND SEE NO REASON TO DEVIATE FROM THIS RIGHT NOW. THE THREAT FOR THUNDER WILL WANE INTO THE OVERNIGHT HOURS AS COOLER AIR ARRIVES WITH THE PASSAGE OF A PACIFIC COLD FRONT OVERNIGHT. SHOWERS WILL CONTINUE TO BE A THREAT THOUGH AS WEAK MID LEVEL LIFT CONTINUES INTO THE OVERNIGHT. STRONG NORTHWESTERLY WINDS WILL DEVELOP BEHIND THE EXITING PACIFIC COLD FRONT LATE SUNDAY NIGHT INTO MONDAY...WHICH WILL KEEP THE BOUNDARY LAYER MIXED OVERNIGHT...LEADING TO MILD TEMPS MONDAY MORNING. THE LATEST NUMERICAL GUIDANCE CAME IN WITH LOWS IN THE UPPER 20S FAR WEST TO THE LOWER 30S ELSEWHERE FOR LOWS MONDAY MORNING. LOOKING AT FORECAST SOUNDINGS AND WITH EXPECTED MIXING...LOWS ON THE ORDER OF MID 30S IN THE WEST...TO UPPER 30S IN THE EAST SEEM TO BE A BETTER FIT TO THE FORECAST SOUNDINGS AND LOWS WERE INCREASED ABOVE THE INHERITED FCST. WITH WARMER LOWS EXPECTED MONDAY MORNING...THE MENTION OF SNOW WAS SCALED BACK TO INCLUDE ONLY THE EASTERN PANHANDLE AND A SLIVER OF THE WESTERN SANDHILLS BETWEEN 09Z AND 15Z MONDAY. ON MONDAY...STRONG PRESSURE RISES BEHIND THE FRONT AND STEEP LAPSE RATES WILL LEAD TO STRONG NORTHERLY WINDS. THE LATEST NUMERICAL GUIDANCE HAS TRENDED STRONGER WITH WINDS THIS MORNING...AND IS INDICATIVE OF ADVISORY SPEED WINDS FROM LATE MORNING MONDAY INTO EARLY TUESDAY EVENING. FOR NOW...HAVE RAMPED UP WINDS IN THE GRIDS AND WILL PROBABLY HAVE THE SHORT TERM DESK MENTION THE WIND THREAT IN THE HWO THIS AFTERNOON. IN ADDITION TO WIND...VERY COLD H500 TEMPS WILL TRACK ACROSS THE CENTRAL AND EASTERN CWA MONDAY AFTERNOON ON THE BACK SIDE OF THE UPPER LEVEL DISTURBANCE. THIS WILL SET THE STAGE FOR VERY STEEP MID LEVEL LAPSE RATES MONDAY AFTERNOON. WITH SURFACE HEATING...CANNOT RULE OUT THE THREAT FOR AFTERNOON SHOWERS IN THE CENTRAL AND EAST AND HAVE LINGERED THEM THROUGH MONDAY EVENING. MONDAY NIGHT AND TUESDAY...DRY AIR...LIGHTER WINDS AND CLEARING WILL ALLOW TEMPERATURES TO DROP QUICKLY MONDAY EVENING. FCST SOUNDINGS ARE INDICATIVE OF A DECENT LOW LEVEL INVERSION SETTING UP MONDAY NIGHT AS WARMER H85 AIR PUSHES INTO THE AREA INTO TUESDAY MORNING. OVERNIGHT LOWS WILL RANGE FROM THE UPPER 20S IN THE VALLEY...TO LOWER 30S ELSEWHERE. ON TUESDAY MORNING...A WARM FRONT WILL LIFT ACROSS THE REGION. MUCH WARMER H85 TEMPS OF 8 TO 14C WILL PUSH INTO THE FORECAST AREA BY 21Z TUESDAY AFTERNOON. WESTERLY WINDS WILL INCREASE DURING THE AFTERNOON HOURS TO 10 TO 20 MPH...AS WELL AND MAY GUST UP TO 25 MPH IN THE AFTERNOON HOURS. THESE WINDS COUPLED WITH DEW POINTS IN THE 20S AND FCST HIGHS IN THE 60S MAY PUSH FIRE DANGER TO EXTREME OR NEAR CRITICAL FOR TUESDAY AFTERNOON. TUESDAY NIGHT THROUGH SATURDAY...IN THE LONG RANGE...THE MAIN FORECAST CHALLENGES ARE TEMPERATURES IN ASSOCIATION WITH A DEVELOPING RIDGE TUESDAY NIGHT AND WEDNESDAY...FOLLOWED BY THE THREAT FOR PCPN LATE NEXT WEEK. ON WEDNESDAY...HIGH AMPLITUDE RIDGING ACROSS THE WESTERN HALF OF THE CONUS WILL BEGIN TO BE SUPPRESSED AS A STRONG SHORTWAVE LIFTS ACROSS SOUTHERN CANADA. HIGHS WEDNESDAY WILL RANGE FROM THE UPPER 70S TO NEAR 80. WITH THE WARM TEMPERATURES...LOW DEW POINTS AND WIND...NEAR CRITICAL TO CRITICAL FIRE DANGER CONDITIONS ARE A STRONG POSSIBILITY AND WILL MENTION THIS IN THE HWO. BY WEDNESDAY NIGHT...RIDGING ALOFT WILL BREAK DOWN AS AN UPPER LEVEL DISTURBANCE TRACKS ACROSS SOUTHERN CANADA AND THE NRN TIER OF STATES. THIS FEATURE WILL FORCE A DRY PACIFIC COLD FRONT THROUGH THE REGION WEDNESDAY NIGHT. TEMPERATURES BEHIND THE FRONT WILL BE IN THE 60S FOR THURSDAY. TEMPERATURES WILL WARM BACK INTO THE MID AND UPPER 60S FOR FRIDAY AND SATURDAY IN ADVANCE OF THE NEXT SRLY STREAM UPPER LEVEL TROUGH. THE LATEST MID RANGE SOLNS ARE INDICATING SOME GULF MOISTURE RETURN AHEAD OF THIS FEATURE...SO WE MAY SEE SOME THUNDERSTORMS FRIDAY NIGHT INTO SATURDAY AS THE TROUGH EJECTS ONTO THE SOUTHERN PLAINS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1155 PM CDT SAT APR 5 2014 VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH SUNDAY EVENING. WEAK SFC FRONT FROM KOGA TO KVTN DRIFTS SOUTH AND GETS HUNG UP FROM KIML TO KONL ON SUNDAY. ISOLATED TO PERHAPS SCATTERED SHRA/ISOLD TSRA ARE EXPECTED TO DEVELOP ALONG OR NEAR THE FRONT SUNDAY AFTN-EVENING. DRY AIR BELOW H700MB SHOULD ALLOW FOR VFR ALL AREAS DURING THE THIS PERIOD. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CLB SHORT TERM...KNUTSVIG LONG TERM...CLB AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
710 PM EDT MON APR 7 2014 .SYNOPSIS... LOW PRESSURE LOCATED IN THE OHIO VALLEY THIS AFTERNOON WILL MOVE NORTHEASTWARD INTO WESTERN PENNSYLVANIA TONIGHT AND INTO SOUTHERN CANADA BY TUESDAY. THIS WILL BRING PERIODS OF RAIN TONIGHT AND INTO TUESDAY...ALONG WITH SOME GUSTY WINDS ALONG THE WESTERN SLOPES. THE COMBINATION OF WARMER TEMPERATURES AND SNOW MELT...ALONG WITH THE EXPECTED RAINFALL WILL PRODUCE MAINLY WITHIN BANK RISES ON LOCAL WATERWAYS...WITH SOME MINOR ICE JAM RELATED FLOODING POSSIBLE BY TUESDAY. COOLER AND DRIER WEATHER WILL BRIEFLY RETURN ON WEDNESDAY BEFORE A WARMING TREND BEGINS HEADING INTO LAKE WEEK. && .NEAR TERM /UNTIL 8 AM TUESDAY MORNING/... AS OF 710 PM EDT MONDAY...LOW- LEVELS REMAIN QUITE DRY EARLY THIS EVENING /DEWPOINTS IN THE 20S RESULTING IN RH VALUES RUNNING IN THE 30-40% RANGE/. THE DRY AIR AT THE SFC IS LIMITING ANY RAIN FROM REACHING THE GROUND DESPITE THE PRESENCE OF WEAK ECHOES ON REGIONAL RADAR. HOWEVER A SUBSTANTIAL SURGE IN DEWPOINTS (MID 30S) IS NOTED WITH THE CURRENT BAND OF STEADIER RAIN ACROSS THE TUG HILL/CENTRAL ADIRONDACKS AREA. THIS INCREASE IN LOW-LEVEL MOISTURE AS WELL AS EVAPORATIVE/WET-BULB COOLING EFFECTS WILL ACT TO QUICKLY SATURATE THE COLUMN INTO MID-EVENING. NO CHANGES TO POPS...WX OR QPF BASED ON RECENT SHORT-RANGE GUIDANCE. WINDS WILL ALSO BE STEADILY INCREASING OVER THE NEXT FEW HOURS AND ESPECIALLY OVERNIGHT. LOW-LEVEL WINDS BEGINNING TO INCREASE PARTICULARLY IN SOUTHERN NY AND PA...NOTING 50 KT SOUTHEASTERLIES AT 850MB AT BGM VWP. THIS LOW-LEVEL JET WILL CONTINUE TO LIFT NORTH AS THE OVERNIGHT PROGRESSES CONTRIBUTING TO GUSTY WINDS AT ELEVATION. PREVIOUS NEAR-TERM DISCUSSION ISSUED AT 322 PM MONDAY FOLLOWS... LOOKING AT A WET AND BREEZY EVENING AND NIGHT FOR THE NORTH COUNTRY AS A LOW PRESSURE SYSTEM CENTERED OVER THE OHIO VALLEY THIS AFTERNOON PUSHES INTO WESTERN PENNSYLVANIA OVERNIGHT AND INTO THE SAINT LAWRENCE VALLEY OF NEW YORK BY TUESDAY MORNING. RAIN HAS MADE IT ABOUT AS FAR NORTH AS SYRACUSE NEW YORK AS OF 230 PM AND WILL CONTINUE ITS STEADY PUSH NORTHEASTWARD AND OVERSPREADING MUCH OF SOUTHERN VERMONT AND NORTHERN NEW YORK BY 8PM AND THE ENTIRE REGION BY 10PM. MOST WIDESPREAD PERIOD OF RAIN WILL OCCUR BETWEEN 8PM AND 4AM WITH INITIAL PUSH OF WARM AIR AND MOISTURE ADVECTION INTO THE REGION. INDICATIONS ARE THAT THE DEEPEST MOISTURE WILL BE SHEARED OFF TO SOUTH AND EAST OVER SOUTHERN NEW ENGLAND WHILE A SECOND AREA OF HEAVIER PRECIPITATION MORE CLOSELY ASSOCIATED WITH THE INLAND LOW WILL TRACK ACROSS NORTHERN NEW YORK. THUS LOOKING AT ABOUT 0.5-0.75" ACROSS SOUTHERN VERMONT...0.5-1.0" ACROSS NORTHERN NEW YORK...WITH ONLY 0.25-0.50" ACROSS MUCH OF CENTRAL AND NORTHERN VERMONT. SOUTHEAST DOWNSLOPE AREAS WILL SEE THE LEAST RAINFALL (WESTERN SLOPES...CHAMPLAIN VALLEY...AND PARTS OF THE NORTHEAST KINGDOM). CANNOT RULE OUT AN ISOLATED RUMBLE OF THUNDER EITHER GIVEN SOME VERY WEAK ELEVATED CAPE (<50 J/KG). THIS AMOUNT OF RAINFALL COMBINED WITH SNOW-MELT AND LINGERING ICE ON AREA RIVERS MAY LEAD TO MINOR FLOOD ISSUES...SEE HYDROLOGY DISCUSSION BELOW. WINDS WILL ALSO BE SOMEWHAT OF A FACTOR OVERNIGHT AS SOUTHEAST LOW LEVEL JET OF 65-75 KNOTS AT 850MB AND 40-50 KNOTS AT 925MB MOVES ACROSS THE REGION. THIS IS EXPECTED TO LEAD TO GUSTS OF 35-45 MPH ALONG THE WESTERN SLOPES OF THE GREEN MOUNTAINS AND 25-35 MPH IN THE CHAMPLAIN VALLEY WITH SOME CHANNELLING. NOT EXPECTING A SIGNIFICANT DOWNSLOPE WIND EVENT AS STRONGEST WINDS SHOULD REMAIN ABOVE THE LOW LEVEL INVERSION. THERE MAY BE SOME SLIGHTLY STRONGER GAP WIND FLOW WITH INVERSION LOCATED BELOW THE MOUNTAINTOP...AS NOTED BY LOW FROUDE NUMBERS. TEMPERATURES OVERNIGHT WILL FALL INITIALLY AS PRECIPITATION MOVES INTO THE REGION...ESPECIALLY WITH LOW DEW POINTS THIS AFTERNOON. LOWS WILL BE GENERALLY 38-43F. NOT EXPECTING IT TO FALL ANY FURTHER WITH STRONG SOUTH FLOW AND INCREASING PRECIPITATION AND MOISTURE. WILL EVEN LIKELY SEE TEMPERATURES RISE THROUGH THE 40S AS THE NIGHT PROGRESSES. AS THE RAIN PULLS OUT OF THE REGION AFTER 4AM...MAY SEE PERIODS OF LINGERING DRIZZLE WITH ABUNDANT LOW LEVEL MOISTURE LASTING INTO THE EARLY MORNING HOURS AND DRY SLOT MOVING IN ALOFT. && .SHORT TERM /8 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 322 PM EDT MONDAY...TUESDAY WILL START IN THE DRY SLOT WITH SURFACE COLD FRONT BACK TO THE WEST. COLD FRONT LOOKS TO CROSS THE REGION DURING THE LATE MORNING AND AFTERNOON HOURS WITH ADDITIONAL CHANCES FOR SCATTERED RAIN SHOWERS. WHILE IN THE DRY SLOT...MAY SEE A BRIEF PERIOD OF CLEARING...WHERE MIXING INCREASES AND SOME GUSTY SOUTHWEST WINDS OF 20-30 MPH DEVELOP. THIS WILL ALSO ALLOW TEMPERATURES TO RISE...WITH HIGHS NUDGING INTO THE UPPER 50S TO AROUND 60 AGAIN FOR PORTIONS OF THE CHAMPLAIN VALLEY AND SOUTHERN VERMONT. SHOULD SEE 45-55F ELSEWHERE...COOLEST ACROSS NORTHERN NEW YORK WHERE BEST CHANCE FOR RAIN SHOWERS LIES...CLOSER TO LOW TRACK. MODEL GUIDANCE ALSO HINTING AT QUICK MOISTURE SURGE PRE- FRONT...WITH DEW POINTS NUDGING CLOSE TO 50F IN A FEW AREAS. THIS MAY LEAD TO SOME WEAK SURFACE-BASED CAPE (<100 J/KG) WHICH MAY LEAD TO SOME CONVECTIVE RAIN SHOWERS. AFTER THE COLD FRONT PASSES...TEMPERATURES WILL SLOWLY FALL AND GUSTY WEST-SOUTHWEST WINDS OF 15-25 MPH CONTINUE. COLD AIR ADVECTION ON NORTHWEST FLOW ENSUES TUESDAY NIGHT WITH CONTINUED CHANCES FOR SOME UPSLOPE RAIN/SNOW SHOWERS...MAINLY HIGHER TERRAIN. LOOKING FOR LOWS TO FALL BACK INTO 30S WITH SOME UPPER 20S POSSIBLE IN THE ADIRONDACKS. MORNING CLOUDS AND LINGERING NORTHWEST UPSLOPE FLOW RAIN/SNOW SHOWERS GIVE WAY TO GRADUAL CLEARING DURING WEDNESDAY AS A RIDGE OF HIGH PRESSURE NOSES IN. HOWEVER...WITH THE CONTINUED NORTHWEST FLOW...TEMPERATURES WILL ONLY REACH THE LOW/MID 40S. SKIES SHOULD CLEAR FOR AT LEAST THE FIRST HALF OF WEDNESDAY NIGHT BEFORE WARM AIR ADVECTION BEGINS IN EARNEST LATE. THIS WILL LEAD TO TEMPERATURES FALLING INTO THE 20S TO AROUND 30 DEGREES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 321 PM EDT MONDAY...NICE STRETCH OF WEATHER ON TAP FOR OUR REGION AS SPRING WILL BE FELT IN FULL FORCE BY LATER IN THE WEEK AND INTO NEXT WEEKEND. LATEST GLOBAL DETEMINISTIC SOLUTIONS REMAIN LARGELY IN AGREEMENT THROUGH THE PERIOD AND WILL LEAN HEAVILY TOWARD A CONSENSUS BLENDED SOLUTION FOR MUCH OF THE FORECAST PERIOD. THIS WILL ADVERTISE HIGH PRESSURE ACROSS THE REGION ON THURSDAY...GIVING WAY TO A WEAK COLD FRONT THURSDAY NIGHT ALONG WITH SCATTERED SHOWER ACTIVITY. HIGH PRESSURE/DRY WEATHER THEN RETURNS BY FRIDAY WITH MEAN H5 HEIGHTS SLOWLY BUILDING INTO THE WEEKEND BEFORE MORE AMPLIFIED FLOW EVOLVES BY EARLY NEXT WEEK WITH A RENEWED SHOWER THREAT. HIGHS GENERALLY IN THE 50S TO AROUND 60...THOUGH EVEN MILDER SUN/MON (60S) AS MORE AMPLIFIED RIDGING DEVELOPS AHEAD OF SLOWLY ADVANCING GREAT LAKES FRONT. INDEED...IF GFS/EURO PROGGED 925 HPA TEMPS OF +15C DO OCCUR ON MONDAY...SOME SPOTS COULD BE LOOKING AT READINGS NEARING 70F. OVERNIGHT LOWS GENERALLY 35 TO 45...THOUGH SLIGHTLY COOLER FRIDAY NIGHT (25 TO 35)...AND WARMER (40S) BY SUNDAY NIGHT UNDER DEEPER SOUTHERLY FLOW. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... THROUGH 18Z TUESDAY...DETERIORATING FLIGHT CONDS EXPECTED OVER THE NEXT 24 HOURS AS LOW PRESSURE AND ASSOCIATED RAINFALL MOVE INTO THE AREA. CIGS INITIALLY VFR THROUGH 00Z...LOWERING TO A MIX OF VFR/MVFR 00-06Z...THEN MVFR/IFR THEREAFTER. MAIN FOCUS OF STEADIER RAINFALLWILL OCCUR IN THE 00-12Z TIME FRAME...AFTER WHICH PCPN TRENDS MORE SCATTERED/SHOWERY. HIGHEST CONFIDENCE OF IFR TO OCCUR AT KMPV/KSLK/KMSS...MAINLY DURING THE 08-15Z TIME FRAME ON TUESDAY. OTHER CONCERN WILL BE LOW LEVEL WIND SHEAR. SOUTHEASTERLY FLOW OF 40-60 KT OFF THE DECK COULD PROVE PROBLEMATIC...BUT CONFIDENCE ONLY AVERAGE ON HOW MUCH OF THIS MIXES DOWN. ALSO A BIT SKEPTICAL OF HIGHER WIND SPEEDS OFFERED BY LATEST RAP PROGS. NONETHELESS...FEEL CONFIDENT ENOUGH TO PLACE SOUTHEASTERLY LLWS FROM 40-50 KT AT MOST TERMINALS DURING THE 03-09Z TIME FRAME DUE TO THIS UNCERTAINTY. OUTLOOK 18Z TUESDAY THROUGH SATURDAY... 18Z TUESDAY THROUGH 00Z WEDNESDAY...LOW PRESSURE MOVES NORTHEAST ACROSS THE SAINT LAWRENCE VALLEY. LIGHT RAIN WILL TAPER TO SCATTERED SHOWERS AND DRIZZLE. MORNING IFR/MVFR...TRENDING VFR WITH OCCNL MVFR THEREAFTER. 00Z WEDNESDAY THROUGH 00Z FRIDAY...VFR AS AREA OF HIGH PRESSURE PASSES SOUTH OF THE REGION. GUSTY SOUTHERLY WINDS DEVELOP THURSDAY. 00Z FRIDAY THROUGH 00Z SATURDAY...VFR WITH POSSIBLE MVFR IN SCATTERED SHOWERS AS WEAK COLD FRONT MOVES ACROSS REGION. 00Z SATURDAY ONWARD...VFR WITH HIGH PRESSURE. && .HYDROLOGY... MODERATE IN BANK RIVER RISES WITH ISOLATED ICE JAMS ARE POSSIBLE...WHICH MAY CREATE LOCALIZED MINOR FLOODING LATE TONIGHT...TUESDAY...AND INTO WEDNESDAY. THE COMBINATION OF WARM TEMPERATURES MELTING THE SNOW PACK (SNOW WATER EQUIVALENT OF 0.75-1.25" MELTED) AND EXPECTED QPF BETWEEN 0.25-1.0" WILL CAUSE MODERATE RISES ON LOCAL WATERWAYS. A FEW ISOLATED ICE JAMS MAY ALSO DEVELOP AND CAUSE ISOLATED AND MINOR LOWLAND FLOODING. HOWEVER MAJOR WIDESPREAD FLOODING IS NOT ANTICIPATED. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...MUCCILLI NEAR TERM...LOCONTO/MUCCILLI SHORT TERM...MUCCILLI LONG TERM...JMG AVIATION...JMG HYDROLOGY...TABER/MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
711 AM EDT SUN APR 6 2014 .SYNOPSIS... HIGH PRESSURE BUILDING INTO THE NORTH COUNTRY TODAY WILL RESULT IN MOSTLY SUNNY SKIES AND SLIGHTLY BELOW NORMAL TEMPERATURES. TONIGHT...WITH CLEAR SKIES AND LIGHT WINDS TEMPERATURES WILL COOL INTO THE 20S...BUT WILL QUICKLY WARM INTO THE 40S AND 50S ON MONDAY WITH SOME HIGH CLOUDS DEVELOPING IN THE AFTERNOON. THESE CLOUDS WILL PRODUCE MAINLY RAIN SHOWERS ON MONDAY NIGHT INTO TUESDAY...WITH MILD TEMPERATURES CONTINUING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 710 AM EDT SUNDAY...UPDATED FCST TO MENTION FLURRIES ACRS THE NORTHERN DACKS AND NORTHERN GREEN MTNS THRU 15Z TODAY. ALSO...HAVE INCREASED THE AREAL COVERAGE OF CLOUDS...BASED ON LATEST IR SATL PICS. THESE LLVL CLOUDS SHOULD BEGIN TO DISSIPATE OVER THE NEXT 1 TO 3 HRS...WITH THE LAST TO CLR EXTREME NORTHEAST VT. STILL ANTICIPATING HIGHS MAINLY IN THE 30S MTNS TO 40S VALLEYS. WATER VAPOR SHOWS AREA OF SUBSIDENCE DEVELOPING BEHIND S/W ENERGY AND BUILDING RIDGE OF HIGH PRES. IR SATL CONTS TO SHOW A SLOW EROSION OF LLVL CLOUDS ACRS OUR CWA THIS MORNING...WITH THE RAP SOUNDINGS HANDLING THIS RH THE BEST. THIS SUPPORTS CLOUDS ACRS NORTHERN VT AND THE NEK THRU 15Z TODAY...BEFORE CLRING FINALLY DEVELOPS. OTHERWISE...SOUNDINGS SUPPORT MIXING TO ABOUT 875MB TODAY AND INDICATE TEMPS BTWN 0 AND -1C AT THIS LEVEL...ADDING 9 TO 10C...SUPPORT HIGHS MAINLY IN THE M/U 40S. HAVE NOTED MAVBTV ONLY 43 FOR TODAY...WL TREND 4 TO 5 DEGREES HIGHER...BUT WL HAVE TO WATCH INFLUENCE OF FROZEN LAKE WATERS ON WESTERLY FLW. FEEL GUIDANCE MAY THINK SNOW PACK IS STILL ACRS THE CPV...BUT RECENT WARM TEMPS HAVE QUICKLY ERODE SNOW COVERAGE IN THE IMMEDIATE CPV. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 415 AM EDT SUNDAY...SFC HIGH PRES ACRS THE MID ATLANTIC STATES AND BUILDING HGHTS ALOFT WL RESULT IN DRY CONDITIONS THRU MONDAY. HAVE NOTED IN THE 00Z GFS WEAK ELONGATED 5H VORT AND SOME MID LVL RH MOVING ACRS OUR EXTREME NORTHERN CWA TONIGHT...WHICH COULD PRODUCE SOME MID LVL CLOUDS. OTHERWISE...TEMPS WL COOL INTO THE UPPER TEENS COLDER VALLEYS TO M/U 20S CPV/SLV. WARMING 925MB TO 850MB THERMAL PROFILES SUGGEST MIDSLOPE THERMAL BELT WL BE DEVELOPING WITH A RIBBON OF TEMPS IN THE U20S TO MID 30S POSSIBLE BTWN 1500 AND 3000 FT TONIGHT. FCST CHALLENGE ON MONDAY WL BE TEMPS...WITH LLVL WAA CONTINUING AHEAD OF NEXT SYSTEM. SOUTH TO SOUTHEAST FLW DEVELOPS ON MONDAY WITH PROGGED 85H TEMPS WARMING BTWN 0 AND 2C. THINKING WARMEST TEMPS WL BE ALONG THE WESTERN SLOPES/CPV (AWAY FROM LAKE CHAMPLAIN) AND PARTS OF THE SLV/WESTERN DACKS. IF WE WERE TO MIX TO 85H COMPLETELY HIGHS COULD APPROACH 60F IN A FEW LOCATIONS...BUT THINKING WITH HIGH CLOUDS DEVELOPING IN THE AFTN TEMPS WL FALL JUST SHORT IN OUR WARMER VALLEYS...MAINLY M/U 50S TO U40S/L50S ELSEWHERE. NAM/ECMWF/GFS ALL SHOW 850 TO 500MB RH FIELDS QUICKLY SPREADING FROM SW TO NE ACRS OUR CWA BTWN 21Z MONDAY AND 00Z TUESDAY...ASSOCIATED WITH INITIAL 5H VORT AND LLVL WAA. IN ADDITION PWS SURGE BTWN 0.50 AND 0.75 AHEAD OF SFC LOW PRES AND DEVELOPING MID/UPPER LVL TROF. HOWEVER...WITH SFC LOW PRES TRACKING TO OUR WEST AND LATEST 00Z NAM/GFS SHOWING PROGGED SE DOWNSLOPING 85H WINDS BTWN 65 AND 75 KNOTS AROUND 06Z TUES. STRONGEST WINDS ARE CLOSELY TIED WITH HEAVIEST PRECIP...WHICH WL LIMIT MIXING BUT STILL COULD SEE GUSTS TO 40 MPH OR SO ALONG THE WESTERN SLOPES/CPV ON MONDAY NIGHT. THIS WL RESULT IN THE TYPICAL TRRN IMPACTED QPF FIELDS WITH HIGHEST VALUES AROUND 0.50 ACRS THE SE UPSLOPE REGIONS OF THE CENTRAL/SOUTHERN GREENS AND PARTS OF THE EASTERN DACKS. ELSEWHERE...QPF ALONG THE WESTERN SLOPES/CPV WL BE SIMILAR TO OUR LAST EVENT...BTWN 0.10 AND 0.20"...WITH SLIGHTLY HIGHER AMOUNTS ACRS THE SLV. MODELS ARE IN VERY GOOD AGREEMENT WITH THE TWO HEAVIEST QPF FIELDS SPLITTING OUR CWA...EITHER TO THE WEST CLOSER TO THE MID/UPPER LVL DYNAMICS AND BETTER 25H JET OR TO OUR SOUTH AND EAST...WHERE PWS ARE HIGHER AND NOSE OF LLVL JET ENHANCES THE MOISTURE ADVECTION OFF THE ATLANTIC. GIVEN THIS TYPE OF SCENARIO...NOT ANTICIPATING ANY HYDRO ISSUES ON MONDAY NIGHT INTO TUESDAY. WE SHOULD SEE SOME MODERATE RISES FROM SNOW MELT ON MONDAY AND EXPECTED QPF MONDAY NIGHT INTO TUESDAY...AND MAYBE AN ISOLATED ICE JAM OR TWO ACRS OUR NORTHERN RIVERS...OTHERWISE NO WIDESPREAD FLOODING IS ANTICIPATED. THE DURATION OF RAIN LOOKS TO BE BTWN 3 AND 6 HRS ON MONDAY NIGHT...BEFORE MID/UPPER LVL DRY SLOT QUICKLY ADVECTS INTO THE REGION AND PRECIP BECMS SCATTERED. SOME WET SNOW OR SLEET WL BE POSSIBLE ABOVE 2500 FT...BUT ONLY MINIMAL ACCUMULATION ANTICIPATED...GIVEN THERMAL PROFILES. TEMPS ON TUESDAY SHOULD WARM BACK INTO THE 50S AHEAD OF SFC COLD FRNT. EXPECTING ANOTHER BRIEF ROUND OF SHOWERS ASSOCIATED WITH BOUNDARY BTWN 15Z AND 21Z TUESDAY...BUT OVERALL RIBBON OF MID LVL MOISTURE IS LIMITED AND BEST DYNAMICS PASS TO OUR NORTH. TEMPS WL CONT TO SUPPORT ADDITIONAL SNOW MELT...EVEN ACRS THE MID/UPPER ELEVATIONS...SO RIVERS WL HAVE TO BE WATCHED. COOLER WEATHER ARRIVES ON TUESDAY NIGHT/WEDS. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 355 AM EDT SUNDAY...AFTER A CHILLY START...IT LOOKS LIKE TEMPERATURES WILL BE ABOVE SEASONAL NORMS THURSDAY THROUGH SATURDAY. CHANCE OF SHOWERS CONTINUES TUESDAY EVENING AS SURFACE LOW DEPARTS AND COLD FRONT MOVES ACROSS THE AREA. CONTINUED CHANCE OF SHOWERS TUESDAY NIGHT INTO WEDNESDAY MORNING DUE TRAILING UPPER TROUGH AND CYCLONIC FLOW REGIME ALOFT...ALONG WITH LOW LEVEL COLD AIR ADVECTION. THIS WILL ALLOW FOR LIGHT SHOWER ACTIVITY TO TRANSITION TO SNOW SHOWERS...ESPECIALLY OVER THE HIGHER ELEVATIONS...WITH SOME LIGHT ACCUMULATIONS POSSIBLE OVER UPSLOPE FAVORED NORTHERN GREENS AND ADIRONDACKS. DRIER CONDITIONS WEDNESDAY AFTERNOON AS UPPER TROUGH DEPARTS AND HIGH PRESSURE BUILDS EAST FROM THE GREAT LAKES. IT WILL BE BRISK AND CHILLY WEDNESDAY WITH HIGHS IN THE UPPER 30S TO MID 40S WITH NORTHWEST WINDS 10-20 MPH AND GUSTY. RIDGE AXIS WILL MOVE EASTWARD ACROSS FORECAST AREA WEDNESDAY NIGHT WITH CLEAR SKIES AND COLD TEMPS EXPECTED WITH LOWS MAINLY IN THE 20S. RIDGE SHIFTS OFF THE EAST COAST THURSDAY WITH BRISK RETURN SOUTH-SOUTHWEST FLOW DEVELOPING. TEMPERATURES REBOUND NICELY WITH HIGHS IN THE MID 50S TO AROUND 60. CHANCE OF RAIN SHOWERS THURSDAY NIGHT INTO FRIDAY MORNING AS WEAK COLD FRONT MOVES SOUTHEASTWARD ACROSS FORECAST AREA. MIN TEMPS THURSDAY NIGHT IN THE MID 30S TO LOWER 40S...WITH HIGHS FRIDAY IN THE 50S. HIGH PRESSURE BUILDS IN FOR FRIDAY NIGHT INTO SATURDAY. IT WILL BE A BIT COOLER FRIDAY NIGHT WITH LOWS 25 TO 35 DEGREES...BUT HIGHS ON SATURDAY WILL CLIMB BACK INTO THE 50S. && .AVIATION /11Z SUNDAY THROUGH THURSDAY/... THROUGH 06Z MONDAY...EXPECT BKN/OVC VFR CONDITIONS TO CONTINUE OVERNIGHT WITH DIMINISHING CLOUD COVER BY 12Z. EXCEPTION WILL BE SLK WHERE MVFR CONDITIONS EXPECTED TILL ABOUT 10Z. DURING SUNDAY...LOOK FOR SKIES TO BECOME SKC BY AFTERNOON AND CONTINUE SUNDAY NIGHT. WINDS WNW 8-15 KTS OVERNIGHT...THEN WEST 8-15 KTS SUNDAY. GUSTS AROUND 20 KTS AT TIMES. WINDS DIMINISH TO LESS THAN 10 KTS SUNDAY EVENING WITH APPROACH OF SURFACE HIGH PRESSURE. OUTLOOK 06Z MONDAY THROUGH THURSDAY... 06Z MONDAY THROUGH 00Z TUESDAY...MAINLY VFR CONDITIONS AS SURFACE HIGH PRESSURE MOVES ACROSS THE REGION. 00Z TUESDAY THROUGH 00Z WEDNESDAY...LOW PRESSURE MOVING OUT OF THE OHIO VALLEY AND PASSING JUST TO OUR WEST WILL BRING WIDESPREAD RAIN MONDAY INTO INTO TUESDAY MORNING...FOLLOWED BY SCATTERED RAIN SHOWERS TUESDAY AFTN. MAINLY MVFR WITH PERIODS OF IFR CONDITIONS LIKELY. 00Z WEDNESDAY THROUGH 18Z WEDNESDAY...GUSTY NORTHWEST WINDS WITH SCATTERED VALLEY RAIN SHOWERS AND POSSIBLE SNOW SHOWERS AT MPV/SLK. INTERVALS OF MVFR CIGS POSSIBLE...ESPECIALLY FOR MPV/SLK. 18Z WEDNESDAY THROUGH 00Z FRIDAY...VFR AS AREA OF HIGH PRESSURE PASSES SOUTH OF THE REGION. GUSTY SOUTHERLY WINDS DEVELOP THURSDAY. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...RJS AVIATION...RJS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
414 AM EDT SUN APR 6 2014 .SYNOPSIS... HIGH PRESSURE BUILDING INTO THE NORTH COUNTRY TODAY WILL RESULT IN MOSTLY SUNNY SKIES AND SLIGHTLY BELOW NORMAL TEMPERATURES. TONIGHT...WITH CLEAR SKIES AND LIGHT WINDS TEMPERATURES WILL COOL INTO THE 20S...BUT WILL QUICKLY WARM INTO THE 40S AND 50S ON MONDAY WITH SOME HIGH CLOUDS DEVELOPING IN THE AFTERNOON. THESE CLOUDS WILL PRODUCE MAINLY RAIN SHOWERS ON MONDAY NIGHT INTO TUESDAY...WITH MILD TEMPERATURES CONTINUING. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 415 AM EDT SUNDAY...WATER VAPOR SHOWS AREA OF SUBSIDENCE DEVELOPING BEHIND S/W ENERGY AND BUILDING RIDGE OF HIGH PRES. IR SATL CONTS TO SHOW A SLOW EROSION OF LLVL CLOUDS ACRS OUR CWA THIS MORNING...WITH THE RAP SOUNDINGS HANDLING THIS RH THE BEST. THIS SUPPORTS CLOUDS ACRS NORTHERN VT AND THE NEK THRU 15Z TODAY...BEFORE CLRING FINALLY DEVELOPS. OTHERWISE...SOUNDINGS SUPPORT MIXING TO ABOUT 875MB TODAY AND INDICATE TEMPS BTWN 0 AND -1C AT THIS LEVEL...ADDING 9 TO 10C...SUPPORT HIGHS MAINLY IN THE M/U 40S. HAVE NOTED MAVBTV ONLY 43 FOR TODAY...WL TREND 4 TO 5 DEGREES HIGHER...BUT WL HAVE TO WATCH INFLUENCE OF FROZEN LAKE WATERS ON WESTERLY FLW. FEEL GUIDANCE MAY THINK SNOW PACK IS STILL ACRS THE CPV...BUT RECENT WARM TEMPS HAVE QUICKLY ERODE SNOW COVERAGE IN THE IMMEDIATE CPV. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 415 AM EDT SUNDAY...SFC HIGH PRES ACRS THE MID ATLANTIC STATES AND BUILDING HGHTS ALOFT WL RESULT IN DRY CONDITIONS THRU MONDAY. HAVE NOTED IN THE 00Z GFS WEAK ELONGATED 5H VORT AND SOME MID LVL RH MOVING ACRS OUR EXTREME NORTHERN CWA TONIGHT...WHICH COULD PRODUCE SOME MID LVL CLOUDS. OTHERWISE...TEMPS WL COOL INTO THE UPPER TEENS COLDER VALLEYS TO M/U 20S CPV/SLV. WARMING 925MB TO 850MB THERMAL PROFILES SUGGEST MIDSLOPE THERMAL BELT WL BE DEVELOPING WITH A RIBBON OF TEMPS IN THE U20S TO MID 30S POSSIBLE BTWN 1500 AND 3000 FT TONIGHT. FCST CHALLENGE ON MONDAY WL BE TEMPS...WITH LLVL WAA CONTINUING AHEAD OF NEXT SYSTEM. SOUTH TO SOUTHEAST FLW DEVELOPS ON MONDAY WITH PROGGED 85H TEMPS WARMING BTWN 0 AND 2C. THINKING WARMEST TEMPS WL BE ALONG THE WESTERN SLOPES/CPV (AWAY FROM LAKE CHAMPLAIN) AND PARTS OF THE SLV/WESTERN DACKS. IF WE WERE TO MIX TO 85H COMPLETELY HIGHS COULD APPROACH 60F IN A FEW LOCATIONS...BUT THINKING WITH HIGH CLOUDS DEVELOPING IN THE AFTN TEMPS WL FALL JUST SHORT IN OUR WARMER VALLEYS...MAINLY M/U 50S TO U40S/L50S ELSEWHERE. NAM/ECMWF/GFS ALL SHOW 850 TO 500MB RH FIELDS QUICKLY SPREADING FROM SW TO NE ACRS OUR CWA BTWN 21Z MONDAY AND 00Z TUESDAY...ASSOCIATED WITH INITIAL 5H VORT AND LLVL WAA. IN ADDITION PWS SURGE BTWN 0.50 AND 0.75 AHEAD OF SFC LOW PRES AND DEVELOPING MID/UPPER LVL TROF. HOWEVER...WITH SFC LOW PRES TRACKING TO OUR WEST AND LATEST 00Z NAM/GFS SHOWING PROGGED SE DOWNSLOPING 85H WINDS BTWN 65 AND 75 KNOTS AROUND 06Z TUES. STRONGEST WINDS ARE CLOSELY TIED WITH HEAVIEST PRECIP...WHICH WL LIMIT MIXING BUT STILL COULD SEE GUSTS TO 40 MPH OR SO ALONG THE WESTERN SLOPES/CPV ON MONDAY NIGHT. THIS WL RESULT IN THE TYPICAL TRRN IMPACTED QPF FIELDS WITH HIGHEST VALUES AROUND 0.50 ACRS THE SE UPSLOPE REGIONS OF THE CENTRAL/SOUTHERN GREENS AND PARTS OF THE EASTERN DACKS. ELSEWHERE...QPF ALONG THE WESTERN SLOPES/CPV WL BE SIMILAR TO OUR LAST EVENT...BTWN 0.10 AND 0.20"...WITH SLIGHTLY HIGHER AMOUNTS ACRS THE SLV. MODELS ARE IN VERY GOOD AGREEMENT WITH THE TWO HEAVIEST QPF FIELDS SPLITTING OUR CWA...EITHER TO THE WEST CLOSER TO THE MID/UPPER LVL DYNAMICS AND BETTER 25H JET OR TO OUR SOUTH AND EAST...WHERE PWS ARE HIGHER AND NOSE OF LLVL JET ENHANCES THE MOISTURE ADVECTION OFF THE ATLANTIC. GIVEN THIS TYPE OF SCENARIO...NOT ANTICIPATING ANY HYDRO ISSUES ON MONDAY NIGHT INTO TUESDAY. WE SHOULD SEE SOME MODERATE RISES FROM SNOW MELT ON MONDAY AND EXPECTED QPF MONDAY NIGHT INTO TUESDAY...AND MAYBE AN ISOLATED ICE JAM OR TWO ACRS OUR NORTHERN RIVERS...OTHERWISE NO WIDESPREAD FLOODING IS ANTICIPATED. THE DURATION OF RAIN LOOKS TO BE BTWN 3 AND 6 HRS ON MONDAY NIGHT...BEFORE MID/UPPER LVL DRY SLOT QUICKLY ADVECTS INTO THE REGION AND PRECIP BECMS SCATTERED. SOME WET SNOW OR SLEET WL BE POSSIBLE ABOVE 2500 FT...BUT ONLY MINIMAL ACCUMULATION ANTICIPATED...GIVEN THERMAL PROFILES. TEMPS ON TUESDAY SHOULD WARM BACK INTO THE 50S AHEAD OF SFC COLD FRNT. EXPECTING ANOTHER BRIEF ROUND OF SHOWERS ASSOCIATED WITH BOUNDARY BTWN 15Z AND 21Z TUESDAY...BUT OVERALL RIBBON OF MID LVL MOISTURE IS LIMITED AND BEST DYNAMICS PASS TO OUR NORTH. TEMPS WL CONT TO SUPPORT ADDITIONAL SNOW MELT...EVEN ACRS THE MID/UPPER ELEVATIONS...SO RIVERS WL HAVE TO BE WATCHED. COOLER WEATHER ARRIVES ON TUESDAY NIGHT/WEDS. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 355 AM EDT SUNDAY...AFTER A CHILLY START...IT LOOKS LIKE TEMPERATURES WILL BE ABOVE SEASONAL NORMS THURSDAY THROUGH SATURDAY. CHANCE OF SHOWERS CONTINUES TUESDAY EVENING AS SURFACE LOW DEPARTS AND COLD FRONT MOVES ACROSS THE AREA. CONTINUED CHANCE OF SHOWERS TUESDAY NIGHT INTO WEDNESDAY MORNING DUE TRAILING UPPER TROUGH AND CYCLONIC FLOW REGIME ALOFT...ALONG WITH LOW LEVEL COLD AIR ADVECTION. THIS WILL ALLOW FOR LIGHT SHOWER ACTIVITY TO TRANSITION TO SNOW SHOWERS...ESPECIALLY OVER THE HIGHER ELEVATIONS...WITH SOME LIGHT ACCUMULATIONS POSSIBLE OVER UPSLOPE FAVORED NORTHERN GREENS AND ADIRONDACKS. DRIER CONDITIONS WEDNESDAY AFTERNOON AS UPPER TROUGH DEPARTS AND HIGH PRESSURE BUILDS EAST FROM THE GREAT LAKES. IT WILL BE BRISK AND CHILLY WEDNESDAY WITH HIGHS IN THE UPPER 30S TO MID 40S WITH NORTHWEST WINDS 10-20 MPH AND GUSTY. RIDGE AXIS WILL MOVE EASTWARD ACROSS FORECAST AREA WEDNESDAY NIGHT WITH CLEAR SKIES AND COLD TEMPS EXPECTED WITH LOWS MAINLY IN THE 20S. RIDGE SHIFTS OFF THE EAST COAST THURSDAY WITH BRISK RETURN SOUTH-SOUTHWEST FLOW DEVELOPING. TEMPERATURES REBOUND NICELY WITH HIGHS IN THE MID 50S TO AROUND 60. CHANCE OF RAIN SHOWERS THURSDAY NIGHT INTO FRIDAY MORNING AS WEAK COLD FRONT MOVES SOUTHEASTWARD ACROSS FORECAST AREA. MIN TEMPS THURSDAY NIGHT IN THE MID 30S TO LOWER 40S...WITH HIGHS FRIDAY IN THE 50S. HIGH PRESSURE BUILDS IN FOR FRIDAY NIGHT INTO SATURDAY. IT WILL BE A BIT COOLER FRIDAY NIGHT WITH LOWS 25 TO 35 DEGREES...BUT HIGHS ON SATURDAY WILL CLIMB BACK INTO THE 50S. && .AVIATION /08Z SUNDAY THROUGH THURSDAY/... THROUGH 06Z MONDAY...EXPECT BKN/OVC VFR CONDITIONS TO CONTINUE OVERNIGHT WITH DIMINISHING CLOUD COVER BY 12Z. EXCEPTION WILL BE SLK WHERE MVFR CONDITIONS EXPECTED TILL ABOUT 10Z. DURING SUNDAY...LOOK FOR SKIES TO BECOME SKC BY AFTERNOON AND CONTINUE SUNDAY NIGHT. WINDS WNW 8-15 KTS OVERNIGHT...THEN WEST 8-15 KTS SUNDAY. GUSTS AROUND 20 KTS AT TIMES. WINDS DIMINISH TO LESS THAN 10 KTS SUNDAY EVENING WITH APPROACH OF SURFACE HIGH PRESSURE. OUTLOOK 06Z MONDAY THROUGH THURSDAY... 06Z MONDAY THROUGH 00Z TUESDAY...MAINLY VFR CONDITIONS AS SURFACE HIGH PRESSURE MOVES ACROSS THE REGION. 00Z TUESDAY THROUGH 00Z WEDNESDAY...LOW PRESSURE MOVING OUT OF THE OHIO VALLEY AND PASSING JUST TO OUR WEST WILL BRING WIDESPREAD RAIN MONDAY INTO INTO TUESDAY MORNING...FOLLOWED BY SCATTERED RAIN SHOWERS TUESDAY AFTN. MAINLY MVFR WITH PERIODS OF IFR CONDITIONS LIKELY. 00Z WEDNESDAY THROUGH 18Z WEDNESDAY...GUSTY NORTHWEST WINDS WITH SCATTERED VALLEY RAIN SHOWERS AND POSSIBLE SNOW SHOWERS AT MPV/SLK. INTERVALS OF MVFR CIGS POSSIBLE...ESPECIALLY FOR MPV/SLK. 18Z WEDNESDAY THROUGH 00Z FRIDAY...VFR AS AREA OF HIGH PRESSURE PASSES SOUTH OF THE REGION. GUSTY SOUTHERLY WINDS DEVELOP THURSDAY. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...TABER NEAR TERM...TABER SHORT TERM...TABER LONG TERM...RJS AVIATION...RJS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1101 PM EDT MON APR 7 2014 .SYNOPSIS... STRONG LOW PRESSURE IN OHIO WILL DRAG A COLD FRONT EASTWARD AND ACROSS THE EASTERN CAROLINAS TUESDAY NIGHT...ENDING THE RISK FOR SHOWERS AND THUNDERSTORMS. LOCALLY HEAVY RAINFALL IS POSSIBLE TONIGHT. DRY WEATHER DEVELOPING WEDNESDAY IS EXPECTED TO PERSIST INTO THE WEEKEND. A WEAK BACKDOOR COLD FRONT MAY MOVE THROUGH THE AREA THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 1100 PM MONDAY...SUBSIDENCE BEHIND A SIGNIFICANT BATCH OF CONVECTION OFFSHORE HAS LED TO A DETERIORATION OF THE PRECIPITATION SHIELD INLAND. REGIONAL RADAR COMPOSITES REVEAL PRECIPITATION SHOULD INCREASE IN COVERAGE AND INTENSITY LATER TONIGHT AS MORE SUBSTANTIAL ECHOES FROM GEORGIA ARRIVE FROM THE SOUTHWEST. 00Z RUC FORECAST SOUNDINGS INDICATE A SIGNIFICANT MOISTENING AND DESTABILIZATION OF THE 950-500 MB LAYER BETWEEN 06-09Z (2 AM - 5 AM) ALONG THE COAST. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... THE TORNADO WATCH HAS BEEN CANCELED AS SURFACE-BASED INSTABILITY HAS VIRTUALLY DISAPPEARED ACROSS ALL BUT THE WILMINGTON METRO AREA WHERE UP TO 250 J/KG OF SBCAPE REMAINS. WITH SURFACE WINDS BECOMING SOUTHWEST LOW-LEVEL SHEAR AND HELICITY PARAMETERS HAVE ALSO DECREASED. FOR THE REMAINDER OF THE NIGHT ANY CONVECTION SHOULD BE ELEVATED IN NATURE...POSING A MUCH REDUCED THREAT FOR SEVERE WEATHER. CONCERN NOW SHIFTS TOWARD A POSSIBLE FLOODING SCENARIO...ESPECIALLY NEAR THE COAST...AS AN EXTREMELY WET AIRMASS (PRECIP WATER AT THE 99TH PERCENTILE AT 1.80 INCHES) INTERACTS WITH A FAVORABLY POSITIONED 200 MB JET STREAK. STRONG SOUTH-SOUTHWEST WINDS AS HIGH AS 50 KNOTS AT 2500 FT/925 MB WILL FEED WARM AND UNSTABLE AIR IN FROM THE SOUTH. ELEVATED INSTABILITY CALCULATED ON RUC SOUNDINGS AS HIGH AS 900 J/KG AT WILMINGTON...550 J/KG AT MYRTLE BEACH...AND 250 J/KG OVER FLORENCE SHOULD ADD HEAVIER CONVECTIVE ELEMENTS WITHIN THE LARGER AREA OF LIGHT TO MODERATE SHOWERS. RAINFALL FROM THIS POINT FORWARD SHOULD REACH UP TO ONE-HALF INCH INLAND AND PERHAPS 1.50 INCHES ALONG THE NC COAST. AN IN-SITU WEDGE DEVELOPED EARLIER TODAY FROM SUBSTANTIAL RAIN FALLING INTO RELATIVELY DRY AIR. THIS DEVELOPED A MESOSCALE RIDGE AND CREATED DIVERGENT LOW-LEVEL WINDS...WITH THE LEADING EDGE OF THIS COLD FRONT MOVING AS FAR SOUTHEAST AS THE GRAND STRAND BEACHES. THIS WEDGE IS BREAKING DOWN AND SOUTHERLY WINDS ARE STARTING TO SHOW UP ACROSS CENTRAL NORTH AND SOUTH CAROLINA. LOOK FOR SOUTH WINDS TO INCREASE IN SPEED OVER THE NEXT 3-5 HOURS AS A LITTLE OF THAT 50 KT LOW LEVEL JET AT 925 MB WORKS ITS WAY DOWN. TEMPERATURES INLAND ARE AT THEIR LOWS NOW AND SHOULD RISE A COUPLE DEGREES OVERNIGHT...WHILE AT THE COAST TEMPERATURES SHOULD SINK DOWN TO THE MID 60S BY DAYBREAK. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...THE FIRST PART OF TUE LOOKS WETTEST ALONG THE COAST AS PRE-FRONTAL CONVECTION MAY NOT PUSH OFFSHORE UNTIL TUE MORNING. ISOLATED TO SCATTERED CONVECTION MAY REDEVELOP WITH HEATING OF THE DAY TUE AHEAD OF A COLD FRONT WHICH WILL BE APPROACHING FROM THE NW AND N. THE FRONT WILL PUSH S OF THE AREA TUE NIGHT AND THIS SHOULD LARGELY END THE RISK FOR CONVECTION. THE UPPER TROUGH WILL SWING OFF THE COAST ON WED. MUCH COLDER AIR WILL BE ARRIVING UPSTAIRS...BUT WITH THE INCREASING INFLUX OF DRY AIR...WILL KEEP POPS NEAR OR JUST BELOW THRESHOLD TO ALLOW FOR THE SMALL RISK FOR A BRIEF SHOWER AS LAPSE RATES STEEPEN. HIGH PRESSURE WILL SETTLE OVERHEAD WED NIGHT. DAYTIME TEMPS THIS PERIOD WILL BE COOLEST ON WED...MAINLY UPPER 60S. LOWS WILL BE COOLEST WED NIGHT...LOWER TO MID 40S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM SUNDAY...HIGH PRESSURE WILL BUILD IN FROM THE WEST THROUGH MID WEEK. A DEEP NW FLOW OF COLD AND DRY AIR BEHIND DEPARTING COLD FRONT ON WED WILL KEEP TEMPS BELOW NORMAL BUT WARM APRIL SUNSHINE WILL OFFSET THE CAA TO BRING TEMPS NEAR 70. THE HIGH PRESSURE WILL MOVE OVERHEAD WED NIGHT ALLOWING FOR MORE IDEAL RADIATIONAL COOLING CONDITIONS AND ALLOWING TEMPS TO DROP OUT DOWN CLOSER TO 40. RIDGE WILL BUILD UP THROUGH THE SOUTHEAST THURS INTO FRI AS DRY HIGH PRESSURE REMAINS OVER THE AREA...GIVING WAY TO A WARMING TREND. PLENTY OF SUNSHINE WILL HELP TEMPS REACH INTO THE 70S ESPECIALLY ONCE THE HIGH SHIFTS OFF THE COAST ON FRI ALLOWING FOR A WARMER AND SLIGHTLY MOISTER RETURN FLOW TO DEVELOP AS WE HEAD INTO THE WEEKEND. BERMUDA HIGH PRESSURE WILL BE IN PLACE ON SATURDAY AS A WEAKENING COLD FRONT ADVANCES TOWARD THE AREA COMING UP AGAINST RIDGE IN PLACE OVER THE SOUTHEAST. HIGH TEMPS WILL REACH ABOVE NORMAL BY THE WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...MVFR/IFR WILL PERSIST THROUGH THE OVERNIGHT HOURS DUE TO LOWERED CIGS ALONG WITH PERIODS OF STEADY HEAVY RAINFALL. MVFR/IFR WILL PERSIST INTO TUESDAY...WITH CONDITIONS IMPROVING TO MVFR THROUGH THE DAY WITH CONTINUING RAINFALL. CONDITIONS BEGIN TO GRADUALLY IMPROVE TOWARDS THE AFTERNOON HOURS WITH LINGERING -RA/LOWERED CIGS POSSIBLE. LATEST RADAR IMAGERY DEPICTS MOST OF THE AREA ENGULFED IN STEADY...HEAVY AT TIMES...RAINFALL. WIDESPREAD MVFR/IFR ACROSS THE AREA THIS EVENING WITH THE EXCEPTION OF VFR AT KCRE/KILM...BUT EXPECT THESE TERMINALS TO TRANSITION TO MVFR OVER THE NEXT HOUR AS RAIN AND LOWERED CIGS MOVE INTO THE AREA. COULD NOT ENTIRELY RULE OUT SOME LINGERING CONVECTION ALONG THE NC COAST...POSSIBLY AFFECTING KILM...BUT CONFIDENCE IS LOW ATTM...AND IF TSRA DOES DEVELOP IT WILL QUICKLY PUSH OFFSHORE. WINDS WILL BE SOUTH-SOUTHWEST THROUGH THE OVERNIGHT HOURS 10-15 KTS...WITH AN INTERMITTENT GUSTS POSSIBLE. INTO TUESDAY...CONDITIONS WILL IMPROVE FROM IFR TO MVFR...AS LOWERED CIGS AND LINGERING RAINFALL CONTINUES. EXPECT CONDITIONS TO POSSIBLY IMPROVE TO VFR TOWARDS THE END OF THE FORECAST PERIOD...ALL DEPENDENT ON RAINFALL TRENDS AND LINGERING LOWERED CIGS. WEST-SOUTHWEST WINDS WILL PREVAIL AOB 15 KTS WITH GUSTS AROUND 20 KTS POSSIBLE. EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS WEDNESDAY. VFR THURSDAY. MORNING FOG POSSIBLE FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1100 PM MONDAY...A LARGE AREA OF THUNDERSTORMS EAST OF CAPE FEAR HAS DISRUPTED THE SMOOTH WIND FIELD...AND CURRENTLY OBSERVED WINDS AT THE BEACHES AND OFFSHORE BUOYS ARE SOUTHEAST TO SOUTH AT 5-15 KNOTS. AS THE NIGHT GOES ON LOOK FOR WINDS TO BECOME MORE SOLIDLY SOUTHERLY WITH SPEEDS INCREASING TO 15-20 KNOTS. CONDITIONS EAST OF CAPE FEAR MAY EVEN DETERIORATE FURTHER WITH 25 KNOT WINDS POSSIBLE OUT BEYOND 10-15 MILES LATE TONIGHT. SEAS HAVEN`T BUDGED OVER THE PAST FEW HOURS BUT SHOULD BEGIN TO BUILD AS WELL LATER TONIGHT DUE TO INCREASING WINDS. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... WINDS HAVE STRUGGLED TO REACH PREDICTED SPEEDS ALL AFTERNOON. THIS HAS HAD A LARGE IMPACT ON SEA HEIGHTS WHICH ARE RUNNING 2-3 FEET BELOW PRIOR PROJECTIONS. OF ALL THE MODEL GUIDANCE AVAILABLE TO US...ONLY THE RUC SEEMS TO HAVE A REASONABLE HANDLE ON THE CURRENT SITUATION. A COLD WEDGE AIRMASS INLAND PUSHED A COLD FRONT ALMOST DOWN TO THE SOUTH CAROLINA BEACHES THIS AFTERNOON. THIS COLD AIR WEDGE IS NOW BEGINNING TO BREAK DOWN...AND WE MAY BE SEEING THE BEGINNING OF A SUSTAINED INCREASE IN SOUTHERLY WINDS WHICH SHOULD CULMINATE IN 15-20 KTS OVERNIGHT ACROSS THE COASTAL WATERS. SHOULD THIS DEVELOP AS EXPECTED...SEAS WILL FINALLY BUILD TOWARD 6 FT OUT BEYOND 10-15 MILES FROM SHORE. FOR THIS REASON THE SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THE NIGHT. RADAR COMPOSITES SHOW A LARGE SHIELD OF RAIN WITH EMBEDDED HEAVIER SHOWERS. SCATTERED THUNDERSTORMS WITH HEAVY RAIN COULD FILL IN OVERNIGHT AS WELL AS UPPER LEVEL DYNAMICS BECOME QUITE FAVORABLE. PREVIOUS DISCUSSION FROM 300 PM FOLLOWS... WARM FRONT WHICH LIFTED WELL NW OF THE WATERS EARLIER TODAY...IS SLOWLY BEING PUSHED BACK TO THE SOUTHEAST THIS AFTERNOON. WHILE IT IS ANTICIPATED THAT THIS BOUNDARY WILL REMAIN WEST OF THE WATERS...LEAVING SOUTHERLY WINDS IN PLACE...CANNOT RULE OUT A BRIEF TURN TO THE NW WITHIN THE INNER WATERS THIS EVENING. OTHERWISE...SOUTHERLY WINDS CURRENTLY AROUND 10 KTS WILL GRADUALLY RISE THROUGH THE EVENING AND INTO TONIGHT...WHILE VEERING SLIGHTLY TO THE SW...BECOMING SW AT 15-25 KTS. THESE WINDS WILL HELP DRIVE SEAS UPWARD FROM THEIR CURRENT 2-3 FT...TO 5-8 FT LATE TONIGHT. WHILE SMALL CRAFT CONDITIONS HAVE NOT MATERIALIZED YET TODAY...STILL EXPECT THEM TO RETURN THIS EVENING...AND THUS THE ONGOING MWW FOR SCA REMAINS UNCHANGED. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH TUE WITH 6 FT SEA PERHAPS LINGERING INTO TUE NIGHT. SW WINDS WILL VEER TO W TUE EVE AND THEN TO NNW BY WED MORNING. SUSTAINED WIND SPEEDS WILL PEAK AROUND 20 KT...STRONGEST TUE INTO WED...THEN SUBSIDING IN THE WAKE OF THE NORTHERLY SURGE...TO LESS THAN 10 KT WED NIGHT. SEAS WILL BE HIGHEST ON TUE...UP TO 6 TO 8 FT. SEAS WILL STEADILY SUBSIDE IN THE WAKE OF THE COLD SURGE...TO 3 FT OR LESS WED NIGHT. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...STRONG N-NW WINDS AS HIGH PRESSURE BUILDS IN ON WED BEHIND COLD FRONT WILL DIMINISH THROUGH THE DAY ALLOWING SEAS TO DROP BELOW SCA THRESHOLDS. WINDS DIMINISH FURTHER THROUGH WED NIGHT INTO THURSDAY AS HIGH PRESSURE MOVES OVERHEAD. SEAS WILL DROP BELOW 3 FT BY WED NIGHT AS WINDS BECOME LIGHT AND VARIABLE. A LIGHT SOUTHERLY RETURN FLOW WILL DEVELOP ON THURS AS THE HIGH MOVES FURTHER OFF SHORE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT TUESDAY FOR AMZ250-252-254- 256. && $$ NEAR TERM...TRA SHORT TERM...RJD LONG TERM...RGZ AVIATION...SGL
AREA FORECAST DISCUSSION
NWS RALEIGH NC
950 PM EDT MON APR 7 2014 .SYNOPSIS...A WARM FRONT LIFTING NORTH INTO NORTH CAROLINA TONIGHT WILL BE OVERTAKEN BY A COLD FRONT APPROACHING FROM THE WEST. ONCE THE COLD FRONT MOVES EAST OF THE AREA ON TUESDAY...HIGH PRESSURE WILL BEGIN TO BUILD EAST TOWARD THE REGION AND EVENTUALLY SETTLE OVERHEAD BY THURSDAY. && .NEAR TERM /THROUGH TUESDAY NIGHT/... AS OF 950 PM MONDAY... REGIONAL SURFACE ANALYSIS IS RATHER COMPLICATED THIS EVENING...WITH A LINGERING TRUE WEDGE FRONT ACROSS THE NORTHWEST PIEDMONT...A RETREATING WARM FROM SLOWLY PENETRATING INTO THE PIEDMONT...A CONVECTIVELY ENHANCED FRONTAL ZONE ALONG THE COAST...AND THE SYNOPTIC COLD FRONT MOVING THROUGH THE TN VALLEY. CURRENTLY...ALL APPRECIABLE INSTABILITY IS CONFINED TO THE COASTAL AREAS...WITH JUST AREAS OF LIGHT TO MODERATE RAIN MOVING NORTHEAST ACROSS THE EASTERN PIEDMONT AND COASTAL PLAIN. REGIONAL RADAR SUGGESTS THIS WILL CONTINUE FOR THE NEXT FEW HOURS...WHILE THE SYNOPTIC COLD FRONT MAKES ITS WAY ACROSS THE MOUNTAINS. THIS BIG QUESTION FOR THE OVERNIGHT PERIOD IS WHETHER OR NOT THERE WILL BE ANY RENEWED DEVELOPMENT ALONG OR AHEAD OF THE FRONT AS IT PUSHES EAST INTO A SLIGHTLY BETTER THERMODYNAMIC ENVIRONMENT....WHERE THE LATEST RAP RUNS SHOW 300-400 J/KG MLCAPE...AIDED BY A POCKET STEEPENING MID- LEVEL LAPSE RATES...REDEVELOPING OVER THE COASTAL PLAIN AFTER MIDNIGHT. FORCING FOR ACCENT ALONG THE COLD FRONT WILL BE AIDED BY INCREASING HEIGHT FALLS ALOFT AS THE UPPER TROUGH AXIS BEGINS TO MAKE A MORE AGGRESSIVE PUSH EAST. HRRR RUNS HAVE YET TO SHOW ANY REDEVELOPMENT...BUT THERE IS A NARROW LINE OF CONVECTION CURRENTLY DEVELOPING OVER NORTHERN GEORGIA. SHOWERS ARE ALSO KICKING UP OVER UPSTATE SC IN WHAT APPEARS TO BE WEAK WARM ADVECTION ALONG THE RETREATING WARM FRONT. DRYING MID-LEVEL AIR ANALYZED AT 700MB SHOULD KEEP THE OVERALL COVERAGE OF SHOWERS/STORM LIMITED...BUT IT SEEMS PLAUSIBLE THAT AN UPWARD TREND IN CONVECTION IS STILL POSSIBLE OVERNIGHT...EITHER WITH THE SHOWERS MOVING OUT OF SC...OR WITH A FORCED LINE OF SHALLOW CONVECTION LATER TONIGHT. FOR THE FORECASTS UPDATE...WILL MAINTAIN CHANCE POPS OVER THE NORTHWEST PIEDMONT...WITH LIKELY POPS TO THE EAST. WILL ALSO ADJUST TEMPS TO REFLECT THE MOVEMENT OF THE WARM FRONT AND TIMING OF THE COLD FRONT. -SMITH TUESDAY AND TUESDAY NIGHT: EXCEPT FOR THE POSSIBILITY OF SOME LINGERING PRECIP ACROSS THE COASTAL PLAIN THROUGH MID MORNING... EXPECT TUESDAY AND TUESDAY NIGHT TO BE DRY...ALTHOUGH LINGERING LOW CLOUDS ARE EXPECTED. THE COLD FRONT...WHICH ACCORDING TO THE GFS STALLS ACROSS THE AREA DURING THE DAY...SHOULD PROGRESS THROUGH THE REST OF THE AREA TUESDAY NIGHT AS THE LOW PULLS AWAY FROM NEW ENGLAND AND THE TROUGH MOVES OFF THE COAST. THE UPPER LEVEL TROUGH AXIS WILL REMAIN WEST OF CENTRAL NC UNTIL TUESDAY NIGHT. EXPECT HIGH TEMPS TUESDAY TO RANGE FROM THE MID 60S NW TO LOWER 70S SE. LOWS TUESDAY NIGHT WILL BE QUITE A BIT COOLER THAN MONDAY NIGHT...MAINLY IN THE MID TO UPPER 40S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 245 PM MONDAY... A MID-LEVEL TROUGH MOVES THROUGH WEDNESDAY...WITH HEIGHT RISES TAKING PLACE WEDNESDAY NIGHT. A WEAK SURFACE TROUGH IS FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA UNDER BROAD SURFACE HIGH PRESSURE...WITH GENERAL SUBSIDENCE ALSO FORECAST OVER THE AREA. A MODEST 850MB THETA-E RIDGE IS IN PLACE OVER CENTRAL NORTH CAROLINA WHILE K INDICES FALL LATE IN THE DAY FROM NEAR 20 TO AROUND ZERO BY NIGHTFALL. JET SUPPORT BY WEDNESDAY IS FORECAST TO BE EAST OF THE AREA WITH ONLY MODEST 850MB LIFT FORECAST BY THE GFS. LIFTED INDICES FALL TO NEAR ZERO IN THE AFTERNOON...AND WHILE MLCAPE IN THE LOWEST KM HARDLY REGISTERS ON THE GFS...1000-500MB LAPSE RATES ARE QUITE STEEP EARLY WEDNESDAY AFTERNOON...AT OR SLIGHTLY GREATER THAN 7.5C/KM. BUFR SOUNDINGS SHOW THE CAP ALOFT IS WEAK...INCREASING AROUND 700MB BY 00Z...BUT FOR THE AFTERNOON UNTIL THEN...IN THE COOL TROUGH ALOFT...AN ISOLATED SHOWER IS POSSIBLE. INCREASING STABILITY WITH AN INCREASING CAP ALOFT DURING WEDNESDAY NIGHT SHOULD KEEP ANY SHOWER DIURNAL IN NATURE. FORTUNATELY...DESPITE THE LOW-LEVEL DRY AIR AND THE STEEP LAPSE RATES...WINDS ALOFT TO 700MB ARE MAINLY AT OR BELOW 25KT...AND MID-LEVEL MOISTURE IS LIMITED IN VOLUME...SO THE POTENTIAL FOR ANY VERY GUSTY WIND WITH A SHOWER IS CURRENTLY LOW. 1000-850MB THICKNESSES FOR WEDNESDAY SUPPORT HIGHS AT LEAST IN THE MID 60S...AND WITH THE COOL TROUGH OVERHEAD WILL LEAN TOWARD THE COOLER MAV GUIDANCE FOR HIGHS ON WEDNESDAY. OVERNIGHT WEDNESDAY NIGHT...GFS BUFR SOUNDINGS SHOW DECOUPLING SHOULD TAKE PLACE...AND THE AIR MASS BECOMES RATHER DRY THROUGH THE COLUMN ESPECIALLY NORTH OF KFAY. UNDER THE SURFACE RIDGE LATE AT NIGHT...GOOD RADIATIONAL COOLING POTENTIAL EXISTS...AND HAVE CONTINUED A TREND COOLER THAN GUIDANCE FOR LOWS...MOSTLY 37 TO 42. IF THIS TREND CONTINUES OR REMAINS EXPECTED...PATCHY FROST WILL BE POSSIBLE PARTICULARLY OVER SOME AREAS ALONG AND NORTH OF ABOUT U.S. 64 AND COULD BE ADDED TO LATER FORECASTS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 245 PM MONDAY... THE LONG-TERM PART OF THE FORECAST WILL FEATURE A SHORTWAVE RIDGE MOVING THROUGH CENTRAL NORTH CAROLINA THURSDAY...FOLLOWED BY INCREASING TROUGHINESS ALOFT FRIDAY AND SATURDAY AS A COLD FRONT MOVES SOUTH TOWARD THE AREA. THE GFS IS WEAKER THAN THE ECMWF WITH THE WAVE ALOFT AND THE FRONT...THOUGH BOTH MODELS...IN ADVANCE OF THE FRONT MOVING INTO CENTRAL NORTH CAROLINA...INCREASE SURFACE RIDGING WEST OVER THE GULF SLIGHTLY SUCH THAT AVAILABLE MOISTURE AND CONVERGENCE MAY DIMINISH AS THE FRONT MOVES SOUTH. REGARDLESS OF THE STRENGTH OF THE UPPER-LEVEL FEATURES...BOTH MODELS SUPPORT WEAKENING OF THE FRONT SO THAT PRECIPITATION CHANCES MAY BE LOW AS THE FRONT MOVES THROUGH. THURSDAY THROUGH FRIDAY DURING THE DAY WILL REMAIN DRY...AND WILL RETAIN THE SMALL CHANCES FOR SHOWERS FOR FRIDAY NIGHT AND INTO SATURDAY FOR NOW AS THE FRONT APPROACHES. BY SATURDAY NIGHT...SUBSIDENCE IN THE WAKE OF WHATEVER IS LEFT OF THE FRONT AND DRIER AIR FORECAST BY THE LONG-TERM GUIDANCE WILL KEEP CHANCES BELOW SLIGHT...CONTINUING THROUGH SUNDAY UNDER SURFACE HIGH PRESSURE. CURRENTLY...AS THE SURFACE HIGH RETREATS MONDAY...AVAILABLE MOISTURE SHOULD INCREASE ALONG WITH THE CHANCES FOR PRECIPITATION. THE ECMWF IS SLOWER THAN THE GFS DUE TO A DEEPER UPPER LOW AS A RESULT OF SOME PHASING OF MODERATE WAVES IN THE NORTHERN AND SOUTHERN STREAMS... WHILE THE GFS IS MORE PROGRESSIVE...INTRODUCING GOOD QPF INTO CENTRAL NORTH CAROLINA DURING THE DAY MONDAY. EVEN THE ECMWF...WITH A FLOW OFF OF THE ATLANTIC...SUGGESTS THE POTENTIAL FOR A SHOWER OR TWO MONDAY...THOUGH WITH BETTER CHANCES HOLDING OFF UNTIL JUST BEYOND THIS LONG-TERM FORECAST PERIOD. THE BEST COURSE OF ACTION CURRENTLY WILL BE TO FOLLOW A CONSENSUS APPROACH WITH SLIGHT CHANCES FOR SHOWERS MONDAY AND GENERAL CHANCES FOR SHOWERS MONDAY NIGHT. DESPITE SYNOPTIC-SCALE DIFFERENCES IN PARTS OF THIS FORECAST PERIOD...THE MOS GUIDANCE FROM BOTH THE MEX AND MEE ARE VERY SIMILAR AND ALSO FAIRLY SIMILAR TO EXPECTATIONS FOR HIGHS BASED UPON 1000- 850MB THICKNESSES. HIGH TEMPERATURES WILL BE FORECAST AROUND 70 THURSDAY AND MOSTLY IN THE MID 70S TO NEAR 80 FOR THE REST OF THIS PART OF THE FORECAST PERIOD. OVERNIGHT LOWS MOSTLY IN THE MID TO UPPER 40S THURSDAY NIGHT...AROUND 50 TO THE MID 50S FRIDAY AND SATURDAY NIGHTS...THEN GRADUALLY WARMING TO LOWS TO AROUND 60 MONDAY NIGHT BASED ON THE CURRENT TIMING OF THE FRONT MOVING THEN TOWARD CENTRAL NORTH CAROLINA. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 800 PM MONDAY... 24 HOUR TAF PERIOD: RAIN WILL OVERSPREAD THE EASTERN HALF OF THE AREA THIS EVENING AND OVERNIGHT...WHILE THE NORTHWESTERN SITES WILL BE MOSTLY DRY WITH SOME LINGERING SHOWERS POSSIBLE. TOUGH FORECAST AS FAR AS FLIGHT CATEGORIES GO TONIGHT...NOT A LOT OF CONFIDENCE AND MOST SITES MAY BE JUMPING AROUND BETWEEN IFR AND VFR. ONE FACTOR IN THIS IS THAT THE WINDS ARE EXPECTED TO STAY GUSTY OVERNIGHT OUT OF THE SOUTH AT 10-15 KTS GUSTING AS HIGH AS 20 KTS...WHICH COULD HELP CLEAR OUT SOME OF THE LOWER CEILINGS TEMPORARILY BUT WITH INCREASED MOISTURE AND LOW DEWPOINT DEPRESSIONS ADVECTING INTO THE AREA LOW CEILINGS ARE POSSIBLE AT ALL SITES OVERNIGHT AND INTO TUESDAY MORNING. VISIBILITIES WILL FAIR A LITTLE BETTER BUT SOME SITES COULD SEE A DROP TO MVFR LEVELS AT VARIOUS POINTS OVERNIGHT. CEILINGS WILL GRADUALLY RISE AFTER SUNRISE TUESDAY AS THE COLD FRONT MOVES THROUGH THE AREA...ACCOMPANIED BY A CHANCE TO NORTHWESTERLY WINDS. EASTERN SITES WILL HOLD ON TO LOWER CEILINGS LONGER INTO THE AFTERNOON THAT NORTHWESTERN SITES. GUSTS TO 15 KTS WILL BE POSSIBLE THROUGH TUESDAY AFTERNOON BUT SHOULD DIMINISH THEREAFTER. KRWI IS STILL HAVING EQUIPMENT ISSUES AND SO AMENDMENTS ARE NOT SCHEDULED FOR THE SITE BUT REGULAR TAFS WILL CONTINUE TO BE RELEASED EVERY 6 HRS. LONG TERM: A SHORTWAVE WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT...POSSIBLY AFFECTING AVIATION CONDITIONS....OTHERWISE MAINLY VFR CONDITIONS EXPECTED FOR THE LONG TERM FORECAST. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...KCP/DJF NEAR TERM...KCP/SMITH SHORT TERM...DJF LONG TERM...DJF AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
802 PM EDT MON APR 7 2014 .SYNOPSIS...AS A LOW PRESSURE SYSTEM TRACKS NORTHEAST INTO THE OHIO VALLEY THROUGH THIS EVENING...A WARM FRONT LIFTS NORTH THROUGH PARTS OF THE CAROLINAS. A COLD FRONT MOVES THROUGH THE REGION FROM THE WEST OVERNIGHT THROUGH TUESDAY. HIGH PRESSURE THEN BUILDS IN FOR WEDNESDAY INTO FRIDAY. && .NEAR TERM /THROUGH TUESDAY NIGHT/... AS OF 245 PM MONDAY... THROUGH TONIGHT: THE SURFACE LOW...ANALYZED OVER WESTERN KY AT 15Z...WILL CONTINUE TO STRENGTHEN AS IT MOVES NORTHEAST TOWARD THE GREAT LAKES TONIGHT. THE WEDGE BOUNDARY EXTENDING FROM THE SURFACE HIGH OVER NEW ENGLAND REMAINS IN PLACE ACROSS THE NW HALF OF THE AREA THIS AFTERNOON. THE WARM FRONT ASSOCIATED WITH THE LOW CONTINUES TO MIGRATE NORTHWARD INTO THE COASTAL PLAIN...ADVECTING WARM MOIST AIR INTO THE SOUTHEAST AND IMPINGING UPON THE WEDGE BOUNDARY. THE GRADIENT IN TEMPERATURE AND DEWPOINT ACROSS THE BOUNDARIES IS APPROXIMATELY 15 DEGREES. TEMPERATURES IN LOCATIONS WITHIN THE WEDGE REMAIN IN THE MID 40S TO NEAR 50 DEGREES...AND IF THE WEDGE REMAINS IN PLACE THROUGH THE EVENING...HIGHS FROM THE TRIAD TO THE TRIANGLE MAY ONLY REACH THE UPPER 40S TO LOW 50S. THAT WILL DEPEND ON WHETHER OR NOT THE ADVANCING WARM FRONT CAN ERODE THE WEDGE...AND IF SO...HOW FAR NORTH AND WEST IT WILL DO SO. OF ALL THE HI-RES CONVECTION ALLOWING MODELS...THE LATEST (15Z) HRRR IS HANDLING THE CURRENT RAINFALL THE BEST. AFTER A BRIEF LULL IN THE RAINFALL COVERAGE...EXPECT ANOTHER ROUND OF RAIN TO MOVE INTO THE AREA FROM THE SOUTHWEST. THE BEST INSTABILITY IS ACROSS THE FAR SOUTHEAST...BUT IS MARGINAL AT BEST...WHILE THE BEST BULK SHEAR (40- 50 KTS) AND 0-1 SRH (300-400 M2/S2) IS WITHIN THE WEDGE. POTENTIAL STILL EXISTS FOR A FEW SEVERE STORMS TO DEVELOP...WITH THE MAIN THREATS BEING DAMAGING WINDS OR AN ISOLATED TORNADO...MAINLY ALONG THE WARM FRONT/WEDGE BOUNDARY AND POINTS SOUTH AND EAST. IF THE HRRR RAINFALL FORECAST PANS OUT...THE SOUTHERN AND EASTERN PORTIONS OF THE AREA COULD GET 1-2 INCHES OF RAIN...LOCALLY HIGHER...WHICH IS CLOSE TO WHAT THE NORTHWEST AND NORTH RECEIVED EARLIER TODAY. SOME MINOR FLOODING IS STILL POSSIBLE IF THAT MUCH RAIN FALLS... ESPECIALLY IN URBAN AREAS AND USUAL TROUBLE SPOTS. OVERNIGHT THE RAINFALL COVERAGE SHOULD DIMINISH AND/OR MOVE OFF TO THE EAST...WHILE A FEW SHOWERS AND POSSIBLE THUNDERSTORM OR TWO WILL BE POSSIBLE JUST AHEAD OF THE COLD FRONT...WHICH SHOULD START TO CROSS CENTRAL NC AROUND MIDNIGHT. THOUGH THE POTENTIAL FOR ONE OF THESE STORMS TO BECOME SEVERE CANNOT BE COMPLETELY RULED OUT...THE TIMING IS NOT FAVORABLE AND THERE IS A GOOD CHANCE THE PRECEDING RAINFALL WILL ACT TO SUFFICIENTLY STABILIZE THE ENVIRONMENT. THE COLD FRONT SHOULD EFFECTIVELY ERODE THE WEDGE OVERNIGHT...BUT HOW FAR EAST IT PROGRESSES BEFORE SUNRISE WILL AFFECT THE LOW TEMPS. FOR NOW EXPECT LOWS AROUND 50 DEGREES NW TO LOW 60S SE. TUESDAY AND TUESDAY NIGHT: EXCEPT FOR THE POSSIBILITY OF SOME LINGERING PRECIP ACROSS THE COASTAL PLAIN THROUGH MID MORNING... EXPECT TUESDAY AND TUESDAY NIGHT TO BE DRY...ALTHOUGH LINGERING LOW CLOUDS ARE EXPECTED. THE COLD FRONT...WHICH ACCORDING TO THE GFS STALLS ACROSS THE AREA DURING THE DAY...SHOULD PROGRESS THROUGH THE REST OF THE AREA TUESDAY NIGHT AS THE LOW PULLS AWAY FROM NEW ENGLAND AND THE TROUGH MOVES OFF THE COAST. THE UPPER LEVEL TROUGH AXIS WILL REMAIN WEST OF CENTRAL NC UNTIL TUESDAY NIGHT. EXPECT HIGH TEMPS TUESDAY TO RANGE FROM THE MID 60S NW TO LOWER 70S SE. LOWS TUESDAY NIGHT WILL BE QUITE A BIT COOLER THAN MONDAY NIGHT...MAINLY IN THE MID TO UPPER 40S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 245 PM MONDAY... A MID-LEVEL TROUGH MOVES THROUGH WEDNESDAY...WITH HEIGHT RISES TAKING PLACE WEDNESDAY NIGHT. A WEAK SURFACE TROUGH IS FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA UNDER BROAD SURFACE HIGH PRESSURE...WITH GENERAL SUBSIDENCE ALSO FORECAST OVER THE AREA. A MODEST 850MB THETA-E RIDGE IS IN PLACE OVER CENTRAL NORTH CAROLINA WHILE K INDICES FALL LATE IN THE DAY FROM NEAR 20 TO AROUND ZERO BY NIGHTFALL. JET SUPPORT BY WEDNESDAY IS FORECAST TO BE EAST OF THE AREA WITH ONLY MODEST 850MB LIFT FORECAST BY THE GFS. LIFTED INDICES FALL TO NEAR ZERO IN THE AFTERNOON...AND WHILE MLCAPE IN THE LOWEST KM HARDLY REGISTERS ON THE GFS...1000-500MB LAPSE RATES ARE QUITE STEEP EARLY WEDNESDAY AFTERNOON...AT OR SLIGHTLY GREATER THAN 7.5C/KM. BUFR SOUNDINGS SHOW THE CAP ALOFT IS WEAK...INCREASING AROUND 700MB BY 00Z...BUT FOR THE AFTERNOON UNTIL THEN...IN THE COOL TROUGH ALOFT...AN ISOLATED SHOWER IS POSSIBLE. INCREASING STABILITY WITH AN INCREASING CAP ALOFT DURING WEDNESDAY NIGHT SHOULD KEEP ANY SHOWER DIURNAL IN NATURE. FORTUNATELY...DESPITE THE LOW-LEVEL DRY AIR AND THE STEEP LAPSE RATES...WINDS ALOFT TO 700MB ARE MAINLY AT OR BELOW 25KT...AND MID-LEVEL MOISTURE IS LIMITED IN VOLUME...SO THE POTENTIAL FOR ANY VERY GUSTY WIND WITH A SHOWER IS CURRENTLY LOW. 1000-850MB THICKNESSES FOR WEDNESDAY SUPPORT HIGHS AT LEAST IN THE MID 60S...AND WITH THE COOL TROUGH OVERHEAD WILL LEAN TOWARD THE COOLER MAV GUIDANCE FOR HIGHS ON WEDNESDAY. OVERNIGHT WEDNESDAY NIGHT...GFS BUFR SOUNDINGS SHOW DECOUPLING SHOULD TAKE PLACE...AND THE AIR MASS BECOMES RATHER DRY THROUGH THE COLUMN ESPECIALLY NORTH OF KFAY. UNDER THE SURFACE RIDGE LATE AT NIGHT...GOOD RADIATIONAL COOLING POTENTIAL EXISTS...AND HAVE CONTINUED A TREND COOLER THAN GUIDANCE FOR LOWS...MOSTLY 37 TO 42. IF THIS TREND CONTINUES OR REMAINS EXPECTED...PATCHY FROST WILL BE POSSIBLE PARTICULARLY OVER SOME AREAS ALONG AND NORTH OF ABOUT U.S. 64 AND COULD BE ADDED TO LATER FORECASTS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 245 PM MONDAY... THE LONG-TERM PART OF THE FORECAST WILL FEATURE A SHORTWAVE RIDGE MOVING THROUGH CENTRAL NORTH CAROLINA THURSDAY...FOLLOWED BY INCREASING TROUGHINESS ALOFT FRIDAY AND SATURDAY AS A COLD FRONT MOVES SOUTH TOWARD THE AREA. THE GFS IS WEAKER THAN THE ECMWF WITH THE WAVE ALOFT AND THE FRONT...THOUGH BOTH MODELS...IN ADVANCE OF THE FRONT MOVING INTO CENTRAL NORTH CAROLINA...INCREASE SURFACE RIDGING WEST OVER THE GULF SLIGHTLY SUCH THAT AVAILABLE MOISTURE AND CONVERGENCE MAY DIMINISH AS THE FRONT MOVES SOUTH. REGARDLESS OF THE STRENGTH OF THE UPPER-LEVEL FEATURES...BOTH MODELS SUPPORT WEAKENING OF THE FRONT SO THAT PRECIPITATION CHANCES MAY BE LOW AS THE FRONT MOVES THROUGH. THURSDAY THROUGH FRIDAY DURING THE DAY WILL REMAIN DRY...AND WILL RETAIN THE SMALL CHANCES FOR SHOWERS FOR FRIDAY NIGHT AND INTO SATURDAY FOR NOW AS THE FRONT APPROACHES. BY SATURDAY NIGHT...SUBSIDENCE IN THE WAKE OF WHATEVER IS LEFT OF THE FRONT AND DRIER AIR FORECAST BY THE LONG-TERM GUIDANCE WILL KEEP CHANCES BELOW SLIGHT...CONTINUING THROUGH SUNDAY UNDER SURFACE HIGH PRESSURE. CURRENTLY...AS THE SURFACE HIGH RETREATS MONDAY...AVAILABLE MOISTURE SHOULD INCREASE ALONG WITH THE CHANCES FOR PRECIPITATION. THE ECMWF IS SLOWER THAN THE GFS DUE TO A DEEPER UPPER LOW AS A RESULT OF SOME PHASING OF MODERATE WAVES IN THE NORTHERN AND SOUTHERN STREAMS... WHILE THE GFS IS MORE PROGRESSIVE...INTRODUCING GOOD QPF INTO CENTRAL NORTH CAROLINA DURING THE DAY MONDAY. EVEN THE ECMWF...WITH A FLOW OFF OF THE ATLANTIC...SUGGESTS THE POTENTIAL FOR A SHOWER OR TWO MONDAY...THOUGH WITH BETTER CHANCES HOLDING OFF UNTIL JUST BEYOND THIS LONG-TERM FORECAST PERIOD. THE BEST COURSE OF ACTION CURRENTLY WILL BE TO FOLLOW A CONSENSUS APPROACH WITH SLIGHT CHANCES FOR SHOWERS MONDAY AND GENERAL CHANCES FOR SHOWERS MONDAY NIGHT. DESPITE SYNOPTIC-SCALE DIFFERENCES IN PARTS OF THIS FORECAST PERIOD...THE MOS GUIDANCE FROM BOTH THE MEX AND MEE ARE VERY SIMILAR AND ALSO FAIRLY SIMILAR TO EXPECTATIONS FOR HIGHS BASED UPON 1000- 850MB THICKNESSES. HIGH TEMPERATURES WILL BE FORECAST AROUND 70 THURSDAY AND MOSTLY IN THE MID 70S TO NEAR 80 FOR THE REST OF THIS PART OF THE FORECAST PERIOD. OVERNIGHT LOWS MOSTLY IN THE MID TO UPPER 40S THURSDAY NIGHT...AROUND 50 TO THE MID 50S FRIDAY AND SATURDAY NIGHTS...THEN GRADUALLY WARMING TO LOWS TO AROUND 60 MONDAY NIGHT BASED ON THE CURRENT TIMING OF THE FRONT MOVING THEN TOWARD CENTRAL NORTH CAROLINA. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 800 PM MONDAY... 24 HOUR TAF PERIOD: RAIN WILL OVERSPREAD THE EASTERN HALF OF THE AREA THIS EVENING AND OVERNIGHT...WHILE THE NORTHWESTERN SITES WILL BE MOSTLY DRY WITH SOME LINGERING SHOWERS POSSIBLE. TOUGH FORECAST AS FAR AS FLIGHT CATEGORIES GO TONIGHT...NOT A LOT OF CONFIDENCE AND MOST SITES MAY BE JUMPING AROUND BETWEEN IFR AND VFR. ONE FACTOR IN THIS IS THAT THE WINDS ARE EXPECTED TO STAY GUSTY OVERNIGHT OUT OF THE SOUTH AT 10-15 KTS GUSTING AS HIGH AS 20 KTS...WHICH COULD HELP CLEAR OUT SOME OF THE LOWER CEILINGS TEMPORARILY BUT WITH INCREASED MOISTURE AND LOW DEWPOINT DEPRESSIONS ADVECTING INTO THE AREA LOW CEILINGS ARE POSSIBLE AT ALL SITES OVERNIGHT AND INTO TUESDAY MORNING. VISIBILITIES WILL FAIR A LITTLE BETTER BUT SOME SITES COULD SEE A DROP TO MVFR LEVELS AT VARIOUS POINTS OVERNIGHT. CEILINGS WILL GRADUALLY RISE AFTER SUNRISE TUESDAY AS THE COLD FRONT MOVES THROUGH THE AREA...ACCOMPANIED BY A CHANCE TO NORTHWESTERLY WINDS. EASTERN SITES WILL HOLD ON TO LOWER CEILINGS LONGER INTO THE AFTERNOON THAT NORTHWESTERN SITES. GUSTS TO 15 KTS WILL BE POSSIBLE THROUGH TUESDAY AFTERNOON BUT SHOULD DIMINISH THEREAFTER. KRWI IS STILL HAVING EQUIPMENT ISSUES AND SO AMENDMENTS ARE NOT SCHEDULED FOR THE SITE BUT REGULAR TAFS WILL CONTINUE TO BE RELEASED EVERY 6 HRS. LONG TERM: A SHORTWAVE WILL MOVE THROUGH THE AREA WEDNESDAY NIGHT...POSSIBLY AFFECTING AVIATION CONDITIONS....OTHERWISE MAINLY VFR CONDITIONS EXPECTED FOR THE LONG TERM FORECAST. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...KCP/DJF NEAR TERM...KCP SHORT TERM...DJF LONG TERM...DJF AVIATION...ELLIS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
743 PM EDT MON APR 7 2014 .SYNOPSIS... STRONG LOW PRESSURE IN OHIO WILL DRAG A COLD FRONT EASTWARD AND ACROSS THE EASTERN CAROLINAS TUESDAY NIGHT...ENDING THE RISK FOR SHOWERS AND THUNDERSTORMS. LOCALLY HEAVY RAINFALL IS POSSIBLE TONIGHT. DRY WEATHER DEVELOPING WEDNESDAY IS EXPECTED TO PERSIST INTO THE WEEKEND. A WEAK BACKDOOR COLD FRONT MAY MOVE THROUGH THE AREA THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 730 PM MONDAY...THE TORNADO WATCH HAS BEEN CANCELED AS SURFACE-BASED INSTABILITY HAS VIRTUALLY DISAPPEARED ACROSS ALL BUT THE WILMINGTON METRO AREA WHERE UP TO 250 J/KG OF SBCAPE REMAINS. WITH SURFACE WINDS BECOMING SOUTHWEST LOW-LEVEL SHEAR AND HELICITY PARAMETERS HAVE ALSO DECREASED. FOR THE REMAINDER OF THE NIGHT ANY CONVECTION SHOULD BE ELEVATED IN NATURE...POSING A MUCH REDUCED THREAT FOR SEVERE WEATHER. CONCERN NOW SHIFTS TOWARD A POSSIBLE FLOODING SCENARIO...ESPECIALLY NEAR THE COAST...AS AN EXTREMELY WET AIRMASS (PRECIP WATER AT THE 99TH PERCENTILE AT 1.80 INCHES) INTERACTS WITH A FAVORABLY POSITIONED 200 MB JET STREAK. STRONG SOUTH-SOUTHWEST WINDS AS HIGH AS 50 KNOTS AT 2500 FT/925 MB WILL FEED WARM AND UNSTABLE AIR IN FROM THE SOUTH. ELEVATED INSTABILITY CALCULATED ON RUC SOUNDINGS AS HIGH AS 900 J/KG AT WILMINGTON...550 J/KG AT MYRTLE BEACH...AND 250 J/KG OVER FLORENCE SHOULD ADD HEAVIER CONVECTIVE ELEMENTS WITHIN THE LARGER AREA OF LIGHT TO MODERATE SHOWERS. RAINFALL FROM THIS POINT FORWARD SHOULD REACH UP TO ONE-HALF INCH INLAND AND PERHAPS 1.50 INCHES ALONG THE NC COAST. AN IN-SITU WEDGE DEVELOPED EARLIER TODAY FROM SUBSTANTIAL RAIN FALLING INTO RELATIVELY DRY AIR. THIS DEVELOPED A MESOSCALE RIDGE AND CREATED DIVERGENT LOW-LEVEL WINDS...WITH THE LEADING EDGE OF THIS COLD FRONT MOVING AS FAR SOUTHEAST AS THE GRAND STRAND BEACHES. THIS WEDGE IS BREAKING DOWN AND SOUTHERLY WINDS ARE STARTING TO SHOW UP ACROSS CENTRAL NORTH AND SOUTH CAROLINA. LOOK FOR SOUTH WINDS TO INCREASE IN SPEED OVER THE NEXT 3-5 HOURS AS A LITTLE OF THAT 50 KT LOW LEVEL JET AT 925 MB WORKS ITS WAY DOWN. TEMPERATURES INLAND ARE AT THEIR LOWS NOW AND SHOULD RISE A COUPLE DEGREES OVERNIGHT...WHILE AT THE COAST TEMPERATURES SHOULD SINK DOWN TO THE MID 60S BY DAYBREAK. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...THE FIRST PART OF TUE LOOKS WETTEST ALONG THE COAST AS PRE-FRONTAL CONVECTION MAY NOT PUSH OFFSHORE UNTIL TUE MORNING. ISOLATED TO SCATTERED CONVECTION MAY REDEVELOP WITH HEATING OF THE DAY TUE AHEAD OF A COLD FRONT WHICH WILL BE APPROACHING FROM THE NW AND N. THE FRONT WILL PUSH S OF THE AREA TUE NIGHT AND THIS SHOULD LARGELY END THE RISK FOR CONVECTION. THE UPPER TROUGH WILL SWING OFF THE COAST ON WED. MUCH COLDER AIR WILL BE ARRIVING UPSTAIRS...BUT WITH THE INCREASING INFLUX OF DRY AIR...WILL KEEP POPS NEAR OR JUST BELOW THRESHOLD TO ALLOW FOR THE SMALL RISK FOR A BRIEF SHOWER AS LAPSE RATES STEEPEN. HIGH PRESSURE WILL SETTLE OVERHEAD WED NIGHT. DAYTIME TEMPS THIS PERIOD WILL BE COOLEST ON WED...MAINLY UPPER 60S. LOWS WILL BE COOLEST WED NIGHT...LOWER TO MID 40S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM SUNDAY...HIGH PRESSURE WILL BUILD IN FROM THE WEST THROUGH MID WEEK. A DEEP NW FLOW OF COLD AND DRY AIR BEHIND DEPARTING COLD FRONT ON WED WILL KEEP TEMPS BELOW NORMAL BUT WARM APRIL SUNSHINE WILL OFFSET THE CAA TO BRING TEMPS NEAR 70. THE HIGH PRESSURE WILL MOVE OVERHEAD WED NIGHT ALLOWING FOR MORE IDEAL RADIATIONAL COOLING CONDITIONS AND ALLOWING TEMPS TO DROP OUT DOWN CLOSER TO 40. RIDGE WILL BUILD UP THROUGH THE SOUTHEAST THURS INTO FRI AS DRY HIGH PRESSURE REMAINS OVER THE AREA...GIVING WAY TO A WARMING TREND. PLENTY OF SUNSHINE WILL HELP TEMPS REACH INTO THE 70S ESPECIALLY ONCE THE HIGH SHIFTS OFF THE COAST ON FRI ALLOWING FOR A WARMER AND SLIGHTLY MOISTER RETURN FLOW TO DEVELOP AS WE HEAD INTO THE WEEKEND. BERMUDA HIGH PRESSURE WILL BE IN PLACE ON SATURDAY AS A WEAKENING COLD FRONT ADVANCES TOWARD THE AREA COMING UP AGAINST RIDGE IN PLACE OVER THE SOUTHEAST. HIGH TEMPS WILL REACH ABOVE NORMAL BY THE WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...MVFR/IFR WILL PERSIST THROUGH THE OVERNIGHT HOURS DUE TO LOWERED CIGS ALONG WITH PERIODS OF STEADY HEAVY RAINFALL. MVFR/IFR WILL PERSIST INTO TUESDAY...WITH CONDITIONS IMPROVING TO MVFR THROUGH THE DAY WITH CONTINUING RAINFALL. CONDITIONS BEGIN TO GRADUALLY IMPROVE TOWARDS THE AFTERNOON HOURS WITH LINGERING -RA/LOWERED CIGS POSSIBLE. LATEST RADAR IMAGERY DEPICTS MOST OF THE AREA ENGULFED IN STEADY...HEAVY AT TIMES...RAINFALL. WIDESPREAD MVFR/IFR ACROSS THE AREA THIS EVENING WITH THE EXCEPTION OF VFR AT KCRE/KILM...BUT EXPECT THESE TERMINALS TO TRANSITION TO MVFR OVER THE NEXT HOUR AS RAIN AND LOWERED CIGS MOVE INTO THE AREA. COULD NOT ENTIRELY RULE OUT SOME LINGERING CONVECTION ALONG THE NC COAST...POSSIBLY AFFECTING KILM...BUT CONFIDENCE IS LOW ATTM...AND IF TSRA DOES DEVELOP IT WILL QUICKLY PUSH OFFSHORE. WINDS WILL BE SOUTH-SOUTHWEST THROUGH THE OVERNIGHT HOURS 10-15 KTS...WITH AN INTERMITTENT GUSTS POSSIBLE. INTO TUESDAY...CONDITIONS WILL IMPROVE FROM IFR TO MVFR...AS LOWERED CIGS AND LINGERING RAINFALL CONTINUES. EXPECT CONDITIONS TO POSSIBLY IMPROVE TO VFR TOWARDS THE END OF THE FORECAST PERIOD...ALL DEPENDENT ON RAINFALL TRENDS AND LINGERING LOWERED CIGS. WEST-SOUTHWEST WINDS WILL PREVAIL AOB 15 KTS WITH GUSTS AROUND 20 KTS POSSIBLE. EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS WEDNESDAY. VFR THURSDAY. MORNING FOG POSSIBLE FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 PM MONDAY...WINDS HAVE STRUGGLED TO REACH PREDICTED SPEEDS ALL AFTERNOON. THIS HAS HAD A LARGE IMPACT ON SEA HEIGHTS WHICH ARE RUNNING 2-3 FEET BELOW PRIOR PROJECTIONS. OF ALL THE MODEL GUIDANCE AVAILABLE TO US...ONLY THE RUC SEEMS TO HAVE A REASONABLE HANDLE ON THE CURRENT SITUATION. A COLD WEDGE AIRMASS INLAND PUSHED A COLD FRONT ALMOST DOWN TO THE SOUTH CAROLINA BEACHES THIS AFTERNOON. THIS COLD AIR WEDGE IS NOW BEGINNING TO BREAK DOWN...AND WE MAY BE SEEING THE BEGINNING OF A SUSTAINED INCREASE IN SOUTHERLY WINDS WHICH SHOULD CULMINATE IN 15-20 KTS OVERNIGHT ACROSS THE COASTAL WATERS. SHOULD THIS DEVELOP AS EXPECTED...SEAS WILL FINALLY BUILD TOWARD 6 FT OUT BEYOND 10-15 MILES FROM SHORE. FOR THIS REASON THE SMALL CRAFT ADVISORY WILL CONTINUE THROUGH THE NIGHT. RADAR COMPOSITES SHOW A LARGE SHIELD OF RAIN WITH EMBEDDED HEAVIER SHOWERS. SCATTERED THUNDERSTORMS WITH HEAVY RAIN COULD FILL IN OVERNIGHT AS WELL AS UPPER LEVEL DYNAMICS BECOME QUITE FAVORABLE. PREVIOUS DISCUSSION FROM 300 PM FOLLOWS... WARM FRONT WHICH LIFTED WELL NW OF THE WATERS EARLIER TODAY...IS SLOWLY BEING PUSHED BACK TO THE SOUTHEAST THIS AFTERNOON. WHILE IT IS ANTICIPATED THAT THIS BOUNDARY WILL REMAIN WEST OF THE WATERS...LEAVING SOUTHERLY WINDS IN PLACE...CANNOT RULE OUT A BRIEF TURN TO THE NW WITHIN THE INNER WATERS THIS EVENING. OTHERWISE...SOUTHERLY WINDS CURRENTLY AROUND 10 KTS WILL GRADUALLY RISE THROUGH THE EVENING AND INTO TONIGHT...WHILE VEERING SLIGHTLY TO THE SW...BECOMING SW AT 15-25 KTS. THESE WINDS WILL HELP DRIVE SEAS UPWARD FROM THEIR CURRENT 2-3 FT...TO 5-8 FT LATE TONIGHT. WHILE SMALL CRAFT CONDITIONS HAVE NOT MATERIALIZED YET TODAY...STILL EXPECT THEM TO RETURN THIS EVENING...AND THUS THE ONGOING MWW FOR SCA REMAINS UNCHANGED. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH TUE WITH 6 FT SEA PERHAPS LINGERING INTO TUE NIGHT. SW WINDS WILL VEER TO W TUE EVE AND THEN TO NNW BY WED MORNING. SUSTAINED WIND SPEEDS WILL PEAK AROUND 20 KT...STRONGEST TUE INTO WED...THEN SUBSIDING IN THE WAKE OF THE NORTHERLY SURGE...TO LESS THAN 10 KT WED NIGHT. SEAS WILL BE HIGHEST ON TUE...UP TO 6 TO 8 FT. SEAS WILL STEADILY SUBSIDE IN THE WAKE OF THE COLD SURGE...TO 3 FT OR LESS WED NIGHT. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...STRONG N-NW WINDS AS HIGH PRESSURE BUILDS IN ON WED BEHIND COLD FRONT WILL DIMINISH THROUGH THE DAY ALLOWING SEAS TO DROP BELOW SCA THRESHOLDS. WINDS DIMINISH FURTHER THROUGH WED NIGHT INTO THURSDAY AS HIGH PRESSURE MOVES OVERHEAD. SEAS WILL DROP BELOW 3 FT BY WED NIGHT AS WINDS BECOME LIGHT AND VARIABLE. A LIGHT SOUTHERLY RETURN FLOW WILL DEVELOP ON THURS AS THE HIGH MOVES FURTHER OFF SHORE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT TUESDAY FOR AMZ250-252-254- 256. && $$ NEAR TERM...TRA SHORT TERM...RJD LONG TERM...RGZ AVIATION...SGL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1136 PM CDT SAT APR 5 2014 .UPDATE... ISSUED AT 1136 PM CDT SAT APR 5 2014 THE LATEST SURFACE MAP SHOWS LOW PRESSURE SOUTH OF SWIFT CURRENT WITH A STATIONARY FRONT SNAKING INTO NORTHWEST AND NORTH CENTRAL NORTH DAKOTA. LOCAL/REGIONAL RADAR SHOWS A SMALL AREA OF SHOWERS ALONG THIS FRONT IN MOUNTRAIL COUNTY MOVING EAST AND WEAKENING WITH TIME. ISOLATED SHOWERS WERE ALSO NOTED IN NORTHEAST MONTANA. BOWMAN RADAR WAS INDICATING POSSIBLE ISOLATED SHOWERS IN THE FAR SOUTHWEST BUT BASED ON SATELLITE AND SURFACE OBSERVATIONS...THE PRECIPITATION APPEARS ALOFT AND NOT REACHING THE GROUND. WILL CONTINUE THE ISOLATED SHOWER MENTION AND SLIGHT CHANCE OF A WINTRY MIX AS TEMPERATURES CONTINUE TO COOL IN THE NORTH. THE HRRR IS ADVERTISING POTENTIAL OF FOG INTO THE TURTLE MOUNTAINS OVERNIGHT. WITH SATURATION HAVING ALREADY BEEN ACHIEVED THERE AND A CALM WIND WITH HIGH PRESSURE OVER RUGBY...FOG IS A POSSIBILITY. THUS HAVE EXPANDED THE PATCHY FOG INTO THE NORTHEAST BASED ON THE ABOVE. OVERALL FORECAST REMAINS IN GOOD SHAPE OVERNIGHT. UPDATE ISSUED AT 943 PM CDT SAT APR 5 2014 LATE EVENING UPDATE FOR MINOR CHANGES TO POPS/WEATHER/TEMPS. A SMALL AREA OF SHOWERS IN PERSISTING IN THE FAR NORTHWEST AND MAY LINGER OVERNIGHT AS A LIGHT WINTRY MIX. HAVE EXPANDED THE AREA OF FOG IN THE SOUTHEAST TO INCLUDE THE ENTIRE JAMES RIVER VALLEY...DUE TO FAVORABLE NAM BUFR SOUNDINGS AND LIGHT WINDS. UPDATE ISSUED AT 631 PM CDT SAT APR 5 2014 EARLY EVENING UPDATE FOR MINOR ADJUSTMENTS TO POPS AND TEMPS. LOWERED MINS TONIGHT SLIGHTLY BASED ON IMPACTS OF MOST SUBSTANTIAL SNOW COVER DURING THE DAY. SPOTTY SHOWERS EXPECTED TO CONTINUE INTO THE EARLY EVENING. A BRIEF WINTRY MIX CAN`T BE RULED OUT ACROSS THE FAR NORTHWEST LATE TONIGHT. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 306 PM CDT SAT APR 5 2014 MAIN FORECAST ISSUES IN THE LONG TERM ARE SHOWER CHANCES YET THIS AFTERNOON AND EARLY EVENING. FOG POTENTIAL LATER TONIGHT...AND TEMPERATURES AND PRECIPITATION CHANCES AGAIN ON SUNDAY. LATEST RADAR AND SATELLITE IMAGERY SHOW A THIN BAND OF SHOWERS EXTENDING FROM AROUND GARRISON AND EXTENDING NORTHEAST TO THE TURTLE MOUNTAINS. THERE HAS BEEN GROUND TRUTH WITH SHOWERS REPORTED AT KMOT...KMIB AND K08D...AND 0.01 AT KMOT. SHORTWAVE OVER NORTH CENTRAL NORTH DAKOTA SHOULD MAINTAIN THIS AREA AS IT MOVES EAST...ALTHOUGH IT MAY BEGIN TO BREAK UP A BIT AS IT MOVES INTO DRIER AIR TO THE EAST. ANYWAY...KEPT SOME SLIGHT CHANCE TO CHANCE POPS ACROSS THE NORTH THIS AFTERNOON. ANOTHER WEAK SHORTWAVE MOVING ACROSS SOUTHERN ALBERTA COULD KEEP CHANCES LINGERING ACROSS THE NORTH INTO THE EVENING HOURS. WITH SOME POPS ALREADY THERE...WILL KEEP THE MENTION GOING...ALTHOUGH WOULD EXPECT STABILIZING ATMOSPHERE MAKING IT HARD FOR ANYTHING SIGNIFICANT AFTER EARLY EVENING. FOG MAY BE POSSIBLE LATER TONIGHT AS WINDS DIMINISH. MOST FAVORED AREAS LOOK TO BE OVER AND NEAR THE SNOW PACK WHERE WINDS ARE EXPECTED TO BE LIGHTEST. EXPECT A LITTLE STRONGER WESTERLY FLOW OVER THE WEST...THUS WILL LIMIT PATCHY FOG TO THE SOUTH CENTRAL INTO THE EAST CENTRAL...OVER SNOW PACK. IF WINDS DO DIMINISH MORE IN THE SOUTHWEST...COULD SEE FOG HERE AS WELL...WITH DEEPEST SNOW REMAINING OVER THIS AREA. ANOTHER SHORTWAVE SLIDING OVER THE AREA IN NORTHWEST FLOW ON SUNDAY. INSTABILITY POTENTIAL LOOKS A LITTLE GREATER...WITH TEMPERATURES SLIGHTLY WARMER MOST AREAS AND INCREASING LAPSE RATES WITH THE SHORTWAVE. SOME MODEL DIFFERENCES IN THE EXACT TRACK OF SHORTWAVE AND ASSOCIATED SURFACE TROUGH...THUS KEPT THE PREVIOUS BROAD BRUSH FOR MENTION OF THUNDER ACROSS THE WEST AND SOUTH CENTRAL. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 306 PM CDT SAT APR 5 2014 SUNDAY NIGHT AND MONDAY...A SIGNIFICANT SHORTWAVE ENERGY IMPULSE EMBEDDED IN A LONGWAVE TROUGH MOVES EASTWARD THROUGH THE STATE...KEEPING A CHANCE OF SHOWERS IN THE FORECAST FOR CENTRAL AND WESTERN NORTH DAKOTA. PRECIPITATION TYPE SHOULD BE RAIN OR SNOW SHOWERS SUNDAY NIGHT/MONDAY MORNING...AND A CHANCE OF RAIN SHOWERS MONDAY AFTERNOON. STRONG UPPER LEVEL RIDGING BUILDING IN FROM THE INTERMOUNTAIN WEST SHOULD KEEP THE FORECAST DRY FOR TUESDAY AND WEDNESDAY. WEDNESDAY WILL BE THE WARMEST DAY OF THE PERIOD WITH HIGHS EXPECTED TO RANGE FROM THE 60S TO AROUND 70 SOUTH. A COLD FRONT IS FORECAST TO SWEEP SOUTHEAST ACROSS NORTH DAKOTA WEDNESDAY NIGHT...BRINGING A CHANCE OF SHOWERS. THE NEXT SIGNIFICANT SHORTWAVE MOVES THROUGH THE STATE FRIDAY AND SATURDAY...WITH A CLIPPER-TYPE SYSTEM. FIRST WE WILL SEE A WARM FRONTAL PASSAGE FRIDAY AHEAD OF A STRONG COLD FRONTAL PASSAGE ON SATURDAY FOLLOWED BY A COOL CANADIAN HIGH MOVING SOUTHEASTWARD FROM THE CANADIAN FRONT RANGE. THIS WILL BRING A CHANCE OF SHOWERS BOTH FRIDAY AND SATURDAY REGARDING MAXIMUM TEMPERATURES...50S MONDAY...WARMING TO 55-65 TUESDAY. THE WARMEST DAY LOOKS TO BE WEDNESDAY WITH HIGHS IN THE 60S MOST AREAS AND APPROACHING 70 FAR SOUTH. THEN 50S THURSDAY AND FRIDAY...WITH 45-55 FOR SATURDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1136 PM CDT SAT APR 5 2014 AN ISOLD WINTRY MIX IS NOT OUT OF THE QUESTION IN FAR NORTHERN NORTH DAKOTA...BUT THE CHANCE OF ANY IMPACTS TO KISN/KMOT ARE LOW. OTHERWISE...EXPECT SCATTERED MAINLY MID LEVEL CLOUDS. KBIS/KJMS ARE FAVORED FOR OVERNIGHT FOG DEVELOPMENT WITH RECENT SNOWMELT AND LIGHT WINDS...SO HAVE ADDED AN EARLY MORNING TEMPO GROUPS. LATER SUNDAY MORNING...WESTERLY WINDS WILL INCREASE WITH GUSTS OVER 20KTS IN THE AFTERNOON. SCATTERED SHOWERS AND AN ISOLATED RUMBLE OF THUNDER POSSIBLE DURING THE AFTERNOON...WITH BEST CHANCES AT KISN/KMOT. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...TWH LONG TERM...JV AVIATION...RPK
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
632 PM EDT SUN APR 6 2014 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA TONIGHT. A DEVELOPING STORM ON THE GULF COAST WILL STRENGTHEN AND MOVE INTO THE OHIO RIVER VALLEY LATE MONDAY AND MONDAY NIGHT BRINGING A WIDESPREAD RAINFALL TO PENNSYLVANIA. HIGH PRESSURE IS EXPECTED TO MAKE A RETURN FOR MID WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... EARLY EVENING VIS SATL IMAGERY SHOWING MAINLY SUNNY SKIES ACROSS CENTRAL PA WITH JUST A BIT OF CIRRUS IN SPOTS. HIGH LVL WAA AHEAD OF DEEPENING MISS VALL TROF WILL SPREAD INCREASING CIRRUS ACROSS THE AREA AFTER DARK. HOW QUICKLY CIRRUS SHIELD ARRIVES WILL DETERMINE HOW COLD IT GETS TONIGHT. CURRENT THINKING BASED ON UPSTREAM SATL TRENDS AND RAP OUTPUT...IS THAT CLOUDS WILL ARRIVE BTWN 01Z-04Z OVR MOST OF CENTRAL PA...BUT REMAIN THIN ENOUGH FOR ADDITIONAL RAD COOLING AND MIN TEMPS IN THE L30S. LATEST MDL OUTPUT CONTINUES TO KEEP THE FCST DRY THROUGH DAWN OVR THE ENTIRE AREA. ALTHOUGH RAIN MAY ARRIVE SHORTLY AFTER 12Z ACROSS THE S TIER. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... MONDAY LOOKS LIKE A WASHOUT AS A DEVELOPING STORM TAKES AIM AT THE ST LAWRENCE RIVER VALLEY...BRINGING A WIDESPREAD OVERRUNNING RAIN TO THE AREA. THE NOSE OF AN ANOMALOUSLY STRONG SSE LLJ WILL BE SURGING THROUGH THE AREA DURING THE DAY MONDAY...PUSHING AN AREA OF ANOMALOUSLY HIGH PWATS INTO THE REGION. ENSEMBLE PLUMES SUGGEST A WIDESPREAD BENEFICIAL RAIN ON THE ORDER OF .50" TO 1.00" STARTING SHORTLY AFTER DAYBREAK IN THE SOUTH...AND REACHING OUR NORTHERN ZONES BY LATE MORNING OR EARLY AFTERNOON. WE WILL REMAIN FIRMLY COLD AIR DAMMED MONDAY...SO TEMPS WILL ONLY REACH THE LOWER TO MID 40S ACROSS THE NORTH...AND THE LOWER 50S ACROSS THE SOUTH. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... AN AMPLIFIED UPPER PATTERN WITH A LONGWAVE TROF OVER THE CENTRAL U.S. AT THE START OF THE PERIOD IS FORECAST TO FLATTEN OUT AND BECOME MAINLY ZONAL TOWARD THE END OF THE WEEK. THE UPPER TROF IS EXPECTED TO SWING EAST OF THE MID ATLANTIC COAST BY LATE WEDNESDAY. COOLER AND UNSETTLED CONDITIONS WILL OCCUR TUESDAY BEHIND THE MONDAYS RAIN-MAKER...AND STICK AROUND EVEN INTO WEDNESDAY AS THE LAGGING UPPER TROUGH SLOWLY PASSES BY. THURSDAY LOOKS MILD AND MAINLY DRY WITH JUST SOME MID AND HIGH CLOUDS BLEEDING ACROSS AHEAD OF THE NEXT FRONTAL SYSTEM THAT WILL BE APPROACHING FOR THE END OF THE WEEK. A GUSTY SW FLOW SHOULD HELP PUSH TEMPS INTO THE UPPER 50S AND 60S BOTH THURSDAY AND FRIDAY. THERE WILL BE A BETTER CHANCE OF SHOWERS FRIDAY WITH A BROAD COLD FRONT EXPECTED TO SAG INTO THE REGION. WITH A LITTLE PUSH FROM THIS SECOND FRONT...THE MAIN INITIAL FRONT WILL HOPEFULLY PUSH SOUTH OF PA...LOWERING THE POPS FOR NEXT SATURDAY. HIGH PRESSURE SHOULD THEN MOVE IN FOR THE SECOND HALF OF NEXT WEEKEND WITH SRLY FLOW MOVING INTO AT LEAST WESTERN PARTS OF THE CWA...ALLOWING FOR FAIR WEATHER AND A CHANCE AT ANOTHER WARM UP. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... NICE DRY...SUNNY AFT. VFR WITH JUST SOME HIGH CLDS. 21Z TAFS SENT. EARLIER DISCUSSION BELOW. HIGH PRESSURE WILL PROVIDE VFR CONDITIONS...WITH GENERALLY CLEAR SKIES AND WINDS UNDER 10 KNOTS TODAY INTO TONIGHT. HIGH CLOUDS WILL BUILD INTO THE AREA TONIGHT...THEN LOWER AND THICKEN RAPIDLY DURING MONDAY AS POTENT LOW PRESSURE TRACKS WEST OF THE REGION. WIDESPREAD MVFR/IFR ALONG WITH RAIN...WILL MOVE INTO THE AREA BETWEEN 14Z AND 18Z MONDAY....AND CONTINUE THROUGH MONDAY NIGHT. LOOK FOR RESTRICTED FLYING CONDITIONS THROUGH EARLY-MID DAY TUESDAY...BEFORE PRECIPITATION TAPERS TO SHOWERS. EXPECT CONDITIONS TO IMPROVE TUESDAY...WITH MANY AREAS RETURNING TO VFR DURING TUESDAY AFTERNOON. HOWEVER...WESTERN MOUNTAINS...KJST UP THROUGH KBFD...MAY CONTINUE WITH LOWER CEILINGS FOR MUCH OF THE DAY IN THE COOL- MOIST NW FLOW. OUTLOOK... .TUE...MVFR WITH SCT SNOW SHOWERS N/W. MVFR TO VFR CNTRL-EAST. .WED...MAINLY VFR. .THU...MAINLY VFR. .FRI...MVFR WITH SCATTERED RAIN SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD/LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
539 PM EDT SUN APR 6 2014 .SYNOPSIS... HIGH PRESSURE WILL MOVE EAST OF THE AREA TONIGHT. A DEVELOPING STORM ON THE GULF COAST WILL STRENGTHEN AND MOVE INTO THE OHIO RIVER VALLEY LATE MONDAY AND MONDAY NIGHT BRINGING A WIDESPREAD RAINFALL TO PENNSYLVANIA. HIGH PRESSURE IS EXPECTED TO MAKE A RETURN FOR MID WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... EARLY EVENING VIS SATL IMAGERY SHOWING MAINLY SUNNY SKIES ACROSS CENTRAL PA WITH JUST A BIT OF CIRRUS IN SPOTS. HIGH LVL WAA AHEAD OF DEEPENING MISS VALL TROF WILL SPREAD INCREASING CIRRUS ACROSS THE AREA AFTER DARK. HOW QUICKLY CIRRUS SHIELD ARRIVES WILL DETERMINE HOW COLD IT GETS TONIGHT. CURRENT THINKING BASED ON UPSTREAM SATL TRENDS AND RAP OUTPUT...IS THAT CLOUDS WILL ARRIVE BTWN 01Z-04Z OVR MOST OF CENTRAL PA...BUT REMAIN THIN ENOUGH FOR ADDITIONAL RAD COOLING AND MIN TEMPS IN THE L30S. LATEST MDL OUTPUT CONTINUES TO KEEP THE FCST DRY THROUGH DAWN OVR THE ENTIRE AREA. ALTHOUGH RAIN MAY ARRIVE SHORTLY AFTER 12Z ACROSS THE S TIER. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... MONDAY LOOKS LIKE A WASHOUT AS A DEVELOPING STORM TAKES AIM AT THE ST LAWRENCE RIVER VALLEY...BRINGING A WIDESPREAD OVERRUNNING RAIN TO THE AREA. THE NOSE OF AN ANOMALOUSLY STRONG SSE LLJ WILL BE SURGING THROUGH THE AREA DURING THE DAY MONDAY...PUSHING AN AREA OF ANOMALOUSLY HIGH PWATS INTO THE REGION. ENSEMBLE PLUMES SUGGEST A WIDESPREAD BENEFICIAL RAIN ON THE ORDER OF .50" TO 1.00" STARTING SHORTLY AFTER DAYBREAK IN THE SOUTH...AND REACHING OUR NORTHERN ZONES BY LATE MORNING OR EARLY AFTERNOON. WE WILL REMAIN FIRMLY COLD AIR DAMMED MONDAY...SO TEMPS WILL ONLY REACH THE LOWER TO MID 40S ACROSS THE NORTH...AND THE LOWER 50S ACROSS THE SOUTH. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... AN AMPLIFIED UPPER PATTERN WITH A LONGWAVE TROF OVER THE CENTRAL U.S. AT THE START OF THE PERIOD IS FORECAST TO FLATTEN OUT AND BECOME MAINLY ZONAL TOWARD THE END OF THE WEEK. THE UPPER TROF IS EXPECTED TO SWING EAST OF THE MID ATLANTIC COAST BY LATE WEDNESDAY. COOLER AND UNSETTLED CONDITIONS WILL OCCUR TUESDAY BEHIND THE MONDAYS RAIN-MAKER...AND STICK AROUND EVEN INTO WEDNESDAY AS THE LAGGING UPPER TROUGH SLOWLY PASSES BY. THURSDAY LOOKS MILD AND MAINLY DRY WITH JUST SOME MID AND HIGH CLOUDS BLEEDING ACROSS AHEAD OF THE NEXT FRONTAL SYSTEM THAT WILL BE APPROACHING FOR THE END OF THE WEEK. A GUSTY SW FLOW SHOULD HELP PUSH TEMPS INTO THE UPPER 50S AND 60S BOTH THURSDAY AND FRIDAY. THERE WILL BE A BETTER CHANCE OF SHOWERS FRIDAY WITH A BROAD COLD FRONT EXPECTED TO SAG INTO THE REGION. WITH A LITTLE PUSH FROM THIS SECOND FRONT...THE MAIN INITIAL FRONT WILL HOPEFULLY PUSH SOUTH OF PA...LOWERING THE POPS FOR NEXT SATURDAY. HIGH PRESSURE SHOULD THEN MOVE IN FOR THE SECOND HALF OF NEXT WEEKEND WITH SRLY FLOW MOVING INTO AT LEAST WESTERN PARTS OF THE CWA...ALLOWING FOR FAIR WEATHER AND A CHANCE AT ANOTHER WARM UP. && .AVIATION /22Z SUNDAY THROUGH FRIDAY/... HIGH PRESSURE WILL PROVIDE VFR CONDITIONS...WITH GENERALLY CLEAR SKIES AND WINDS UNDER 10 KNOTS TODAY INTO TONIGHT. HIGH CLOUDS WILL BUILD INTO THE AREA TONIGHT...THEN LOWER AND THICKEN RAPIDLY DURING MONDAY AS POTENT LOW PRESSURE TRACKS WEST OF THE REGION. WIDESPREAD MVFR/IFR ALONG WITH RAIN...WILL MOVE INTO THE AREA BETWEEN 14Z AND 18Z MONDAY....AND CONTINUE THROUGH MONDAY NIGHT. LOOK FOR RESTRICTED FLYING CONDITIONS THROUGH EARLY-MID DAY TUESDAY...BEFORE PRECIPITATION TAPERS TO SHOWERS. EXPECT CONDITIONS TO IMPROVE TUESDAY...WITH MANY AREAS RETURNING TO VFR DURING TUESDAY AFTERNOON. HOWEVER...WESTERN MOUNTAINS...KJST UP THROUGH KBFD...MAY CONTINUE WITH LOWER CEILINGS FOR MUCH OF THE DAY IN THE COOL- MOIST NW FLOW. OUTLOOK... .TUE...MVFR WITH SCT SNOW SHOWERS N/W. MVFR TO VFR CNTRL-EAST. .WED...MAINLY VFR. .THU...MAINLY VFR. FRI...MVFR WITH SCATTERED RAIN SHOWERS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...FITZGERALD/LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1052 PM CDT MON APR 7 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 415 PM CDT MON APR 7 2014 SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE THROUGH THE LATE AFTERNOON...AND IN THE EAST THIS EVENING AS SHORT WAVE DROPS SOUTHEAST OVER THE AREA. THE AIR OF COURSE IS VERY UNSTABLE IN THE LOWER TO MIDDLE LEVELS WITH THE HEATING...AND SUPPORT FROM THE UPPER WAVE WILL KEEP SOME OF THE HIGHER BASED CONVECTION GOING THIS EVENING...WITH ACTIVITY DECREASING STEADILY FROM THE WEST AS THE LOSS OF HEATING COMBINES WITH THE SYSTEM MOVEMENT. AS WE HAVE BEEN MENTIONING...NO SEVERE WEATHER EXPECTED BUT AN ISOLATED AND BRIEF 45 MPH GUST AND/OR SMALL HAIL EVENT POSSIBLE. CURRENT TIMING EXPECTATIONS REMAIN FOR ACTIVITY TO BE GONE AROUND 06Z/1 AM CDT BUT MAY SLOW THAT DOWN A TAD IN THE FAR EAST IF LATEST HRRR INDICATIONS REMAIN CONSISTENT. OTHERWISE...SKIES SHOULD CLEAR STEADILY FROM THE WEST DURING THE NIGHT AND NORTHWEST WINDS WILL DROP OFF. TUESDAY SHOULD BE FAIRLY SUNNY...WITH SOME WARM ADVECTION HIGH AND SOME MIDDLE CLOUDS MOVING ACROSS MAINLY THE NORTHERN PART OF OUR FORECAST AREA...BUT THE DRY AIR AND GREATER STABILITY WILL PRECLUDE THE LOWER CLOUD DEVELOPMENT. THE NORTHWEST BREEZE WILL BE SLIGHTLY REVITALIZED WITH HEATING UNTIL THE SURFACE RIDGE MOVES OVER THE AREA LATE IN THE DAY. TEMPERATURES LOOK CLOSE TO WHAT WE HAVE BEEN GOING FOR WITH 50S NORTH AND EAST TO THE MID 60S SOUTHWEST. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 415 PM CDT MON APR 7 2014 WINDS SHOULD LAY DOWN A BIT EARLY TUESDAY EVENING WITH RIDGE AXIS ALONG AND DRIFTING EAST OF I29...BUT SOON A STRONGER RETURN FLOW EXPECTED TO DEVELOP ACROSS THE AREA. WITH FLOW DIRECTION AND STRENGTH OF GRADIENT...WINDS ALOFT COULD ATTEMPT TO SURFACE TO A GREATER DEGREE ALONG AND DOWNSTREAM OF THE BUFFALO RIDGE LATER TUESDAY NIGHT. WEDNESDAY REMAINS LIKELY THE WARMEST OVERALL DAY IN LAST SIX MONTHS...WITH SOME LOCATIONS LIKELY TO PUSH TOWARD 80 DEGREES IN THE JAMES TO LOWER MISSOURI VALLEY. SHOULD BE ENOUGH SUNSHINE TO SUPPORT THE WARM TEMPS...ALONG WITH A FAVORABLE SOUTHWEST FLOW DIRECTION WHICH IS A SOLID MATCH FOR EXTREME EVENT CLIMATOLOGY WARMEST MAX. ONE PLACE WHERE GUIDANCE SEEMINGLY COMES UP SHORT IS ON DEWPOINTS...AND WITH GREAT MIXING DEPTHS INDICATED ON ALL OPERATIONAL GUIDANCE...WOULD SUPPORT MUCH LOWER DEWPOINTS THAN THE UPPER 30S TO MID 40S. LOWERED QUITE A BIT IN THE FORECAST GRIDS... AND THIS HAS CREATED SOME GREATER CONCERN FOR FIRE WEATHER /SEE DISCUSSION BELOW/. ON WEDNESDAY NIGHT...WAVE CRASHING THE RIDGE WILL CLIP BETTER DYNAMICS ACROSS THEN NORTHEAST HALF OF THE CWA. OVERALL...THE WELL MIXED ATMOSPHERE IS QUITE DRY...WITH ANY DECENT MOISTURE COMING IN WITH MID LEVEL FRONTAL PASSAGE LATER IN THE NIGHT. BY THIS TIME...HAS BECOME EVEN MORE DRY AT LOW LEVELS...AND WITH STRONG FRONTOGENETIC FORCING...WILL PROBABLY HAVE MUCH MORE RETURNS ON RADAR THAN ACTUALLY REACH THE SURFACE. HAVE CONTINUED FAIRLY LOW POPS MAXIMIZING NORTHEAST VERSUS SOUTHWEST GOING THROUGH THE NIGHT. IF WAS JUST A BIT MORE UNSTABLE...WOULD ENTERTAIN SOMEWHAT HIGHER POPS. THURSDAY ANOTHER FAIRLY BREEZY DAY...WITH MOST OF THE WINDS DUE TO GOOD MIXING ENVIRONMENT. LOW DEWPOINTS WILL AGAIN ENHANCE CONCERN WITH FIRE BEHAVIOR. CONSERVATIVE MIXING YIELDS A LOT OF MID 50S TO NEAR 60...AND HAVE NUDGED JUST A BIT ABOVE THIS DUE TO THE GREAT MIXING CONDITIONS. WEAK WAVE THURSDAY NIGHT...BUT OTHER THAN A FEW MORE CLOUDS HAVE LEFT DRY FOR THE TIME. SHORT WAVE RIDGING AGAIN REBOUNDS ON FRIDAY...AND AGAIN A SOUTH TO SOUTHWEST FLOW ALONG WITH WARMING TEMPS LOOK TO BRING UPPER 60S TO LOWER 70S BACK TO THE AREA. WILL SEE AN INCREASE IN HIGHER CLOUDS DURING THE AFTERNOON HOURS. RAPID NORTHWEST FLOW WILL CONTINUE TO FIRE WAVES THROUGH THE REGION WITH THE NEXT ON FRIDAY NIGHT. MAINLY DRY...BUT BY LATER IN THE NIGHT MAY GET ENOUGH ELEVATED MOISTURE RETURN TON INTERACT WITH MID LEVEL BOUNDARY TO GET A FEW SHOWERS/ISOLATED THUNDER OVER THE NORTHEASTERN CWA. SATURDAY IS AN INTERESTING DAY AS A BOUNDARY WILL BEGIN TO PUSH ACROSS THE CWA. POTENTIAL THAT LEADING WAVE COULD SET UP A PREFRONTAL CONVERGENCE ZONE ACROSS NORTHWEST IOWA THAT WILL FOCUS SOMETHING MORE INSTABILITY DRIVEN DURING THE AFTERNOON AHEAD OF THE FRONT...WHILE COLD FRONT IS MORE INERT BACK BETWEEN I29 AND THE JAMES RIVER. ENOUGH UNCERTAINTY THAT HAVE SPREAD OUT POPS A BIT MORE THAN WOULD NORMALLY DO. ALSO...THIS OPENS UP POTENTIAL FOR TEMPS TO GET QUITE WARM BETWEEN THE LOWER LEVEL MOISTURE SURGE AHEAD OF THE PREFRONTAL TROUGH AND THE ACTUAL COLD FRONT TO THE WEST...WHERE SOME 925 HPA TEMPS ONCE AGAIN BRING CHANCES FOR 70S BACK. WOULD CERTAINLY HAVE TO MONITOR THIS FOR POTENTIAL SEVERE STORMS GIVEN THE SHEAR WITH FAIRLY STRONG MID LEVEL FLOW...AND SOME POTENTIAL ENHANCEMENT TO THE LOWER LEVELS NEAR THE PREFRONTAL TROUGH. FAIRLY MINIMAL AGREEMENT IN LARGER SCALE TOWARD THE END OF THE WEEKEND...BUT TRENDING TOWARD A MORE COHERENT TROUGHINESS BY MONDAY. THIS WOULD AGREE SOMEWHAT WITH GFS IS ONLY SLOWED BY A 12-24H PERIOD. TEMPS COULD END UP SOMEWHAT COLDER ON MONDAY GIVEN A STRAIGHT ECMWF TYPE SOLUTION...LESS PROGRESSIVE THAN THE GFS. ECMWF WOULD SUGGEST THAT WAVE HANGING BACK IN THE SOUTHERN STREAM WOULD START TO PULL NORTHWARD AS SHARPER NORTHERN STREAM WAVE DIGS INTO THE NORTHERN PLAINS ON SUNDAY..SLOWING MID LEVEL BOUNDARY AND ENHANCING THREAT OF PRECIPITATION...ESPECIALLY ACROSS THE SOUTHEAST. NOT AS ENTHUSIASTIC ABOUT COOLING ALONG WITH PRECIP...WITH PERHAPS A LITTLE CHANGE TO SNOW OCCURRING AROUND SUNDAY NIGHT...UNLIKE THE GFS WHICH GOES ALL IN FOR A MIX OR CHANGE TOWARD THE END OF PRECIPITATION AS EARLY AS LATE SATURDAY NIGHT. FOR THE TIME... HAVE WEIGHTED ECMWF SOLUTION QUITE A BIT MORE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1049 PM CDT MON APR 7 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. && .FIRE WEATHER... WILL BE ON THE LOOKOUT FOR A POTENTIAL FOR A CRITICAL FIRE WEATHER DAY ON WEDNESDAY. THIS LOOKS TO BE A CLASSIC MIXING DAY AHEAD OF APPROACHING FRONT WEDNESDAY NIGHT...WITH DEEP MIXING LIKELY DRIVING DEWPOINTS QUITE LOW. AT THIS TIME...LOOKING FOR AFTERNOON RELATIVE HUMIDITIES TO RANGE FROM 25 TO 30 PERCENT EAST...TO 15 TO 20 PERCENT MISSOURI AND JAMES VALLEYS. WINDS WILL BE MARGINAL FOR PRODUCING CRITICAL FIRE BEHAVIOR...AND WILL BE REEVALUATING FOR A POSSIBLE FIRE WEATHER WATCH ON MID SHIFT. THURSDAY WILL ALSO BRING POTENTIAL FOR A VERY HIGH FIRE DANGER WITH AGAIN SOME MARGINALLY STRONG NORTHWEST WINDS...AND DRY DEWPOINTS KNOCKING AFTERNOON HUMIDITIES TO 25 TO 30 PERCENT MANY AREAS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM... LONG TERM...CHAPMAN AVIATION... FIRE WEATHER...CHAPMAN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
655 PM CDT MON APR 7 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 415 PM CDT MON APR 7 2014 SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE THROUGH THE LATE AFTERNOON...AND IN THE EAST THIS EVENING AS SHORT WAVE DROPS SOUTHEAST OVER THE AREA. THE AIR OF COURSE IS VERY UNSTABLE IN THE LOWER TO MIDDLE LEVELS WITH THE HEATING...AND SUPPORT FROM THE UPPER WAVE WILL KEEP SOME OF THE HIGHER BASED CONVECTION GOING THIS EVENING...WITH ACTIVITY DECREASING STEADILY FROM THE WEST AS THE LOSS OF HEATING COMBINES WITH THE SYSTEM MOVEMENT. AS WE HAVE BEEN MENTIONING...NO SEVERE WEATHER EXPECTED BUT AN ISOLATED AND BRIEF 45 MPH GUST AND/OR SMALL HAIL EVENT POSSIBLE. CURRENT TIMING EXPECTATIONS REMAIN FOR ACTIVITY TO BE GONE AROUND 06Z/1 AM CDT BUT MAY SLOW THAT DOWN A TAD IN THE FAR EAST IF LATEST HRRR INDICATIONS REMAIN CONSISTENT. OTHERWISE...SKIES SHOULD CLEAR STEADILY FROM THE WEST DURING THE NIGHT AND NORTHWEST WINDS WILL DROP OFF. TUESDAY SHOULD BE FAIRLY SUNNY...WITH SOME WARM ADVECTION HIGH AND SOME MIDDLE CLOUDS MOVING ACROSS MAINLY THE NORTHERN PART OF OUR FORECAST AREA...BUT THE DRY AIR AND GREATER STABILITY WILL PRECLUDE THE LOWER CLOUD DEVELOPMENT. THE NORTHWEST BREEZE WILL BE SLIGHTLY REVITALIZED WITH HEATING UNTIL THE SURFACE RIDGE MOVES OVER THE AREA LATE IN THE DAY. TEMPERATURES LOOK CLOSE TO WHAT WE HAVE BEEN GOING FOR WITH 50S NORTH AND EAST TO THE MID 60S SOUTHWEST. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 415 PM CDT MON APR 7 2014 WINDS SHOULD LAY DOWN A BIT EARLY TUESDAY EVENING WITH RIDGE AXIS ALONG AND DRIFTING EAST OF I29...BUT SOON A STRONGER RETURN FLOW EXPECTED TO DEVELOP ACROSS THE AREA. WITH FLOW DIRECTION AND STRENGTH OF GRADIENT...WINDS ALOFT COULD ATTEMPT TO SURFACE TO A GREATER DEGREE ALONG AND DOWNSTREAM OF THE BUFFALO RIDGE LATER TUESDAY NIGHT. WEDNESDAY REMAINS LIKELY THE WARMEST OVERALL DAY IN LAST SIX MONTHS...WITH SOME LOCATIONS LIKELY TO PUSH TOWARD 80 DEGREES IN THE JAMES TO LOWER MISSOURI VALLEY. SHOULD BE ENOUGH SUNSHINE TO SUPPORT THE WARM TEMPS...ALONG WITH A FAVORABLE SOUTHWEST FLOW DIRECTION WHICH IS A SOLID MATCH FOR EXTREME EVENT CLIMATOLOGY WARMEST MAX. ONE PLACE WHERE GUIDANCE SEEMINGLY COMES UP SHORT IS ON DEWPOINTS...AND WITH GREAT MIXING DEPTHS INDICATED ON ALL OPERATIONAL GUIDANCE...WOULD SUPPORT MUCH LOWER DEWPOINTS THAN THE UPPER 30S TO MID 40S. LOWERED QUITE A BIT IN THE FORECAST GRIDS... AND THIS HAS CREATED SOME GREATER CONCERN FOR FIRE WEATHER /SEE DISCUSSION BELOW/. ON WEDNESDAY NIGHT...WAVE CRASHING THE RIDGE WILL CLIP BETTER DYNAMICS ACROSS THEN NORTHEAST HALF OF THE CWA. OVERALL...THE WELL MIXED ATMOSPHERE IS QUITE DRY...WITH ANY DECENT MOISTURE COMING IN WITH MID LEVEL FRONTAL PASSAGE LATER IN THE NIGHT. BY THIS TIME...HAS BECOME EVEN MORE DRY AT LOW LEVELS...AND WITH STRONG FRONTOGENETIC FORCING...WILL PROBABLY HAVE MUCH MORE RETURNS ON RADAR THAN ACTUALLY REACH THE SURFACE. HAVE CONTINUED FAIRLY LOW POPS MAXIMIZING NORTHEAST VERSUS SOUTHWEST GOING THROUGH THE NIGHT. IF WAS JUST A BIT MORE UNSTABLE...WOULD ENTERTAIN SOMEWHAT HIGHER POPS. THURSDAY ANOTHER FAIRLY BREEZY DAY...WITH MOST OF THE WINDS DUE TO GOOD MIXING ENVIRONMENT. LOW DEWPOINTS WILL AGAIN ENHANCE CONCERN WITH FIRE BEHAVIOR. CONSERVATIVE MIXING YIELDS A LOT OF MID 50S TO NEAR 60...AND HAVE NUDGED JUST A BIT ABOVE THIS DUE TO THE GREAT MIXING CONDITIONS. WEAK WAVE THURSDAY NIGHT...BUT OTHER THAN A FEW MORE CLOUDS HAVE LEFT DRY FOR THE TIME. SHORT WAVE RIDGING AGAIN REBOUNDS ON FRIDAY...AND AGAIN A SOUTH TO SOUTHWEST FLOW ALONG WITH WARMING TEMPS LOOK TO BRING UPPER 60S TO LOWER 70S BACK TO THE AREA. WILL SEE AN INCREASE IN HIGHER CLOUDS DURING THE AFTERNOON HOURS. RAPID NORTHWEST FLOW WILL CONTINUE TO FIRE WAVES THROUGH THE REGION WITH THE NEXT ON FRIDAY NIGHT. MAINLY DRY...BUT BY LATER IN THE NIGHT MAY GET ENOUGH ELEVATED MOISTURE RETURN TON INTERACT WITH MID LEVEL BOUNDARY TO GET A FEW SHOWERS/ISOLATED THUNDER OVER THE NORTHEASTERN CWA. SATURDAY IS AN INTERESTING DAY AS A BOUNDARY WILL BEGIN TO PUSH ACROSS THE CWA. POTENTIAL THAT LEADING WAVE COULD SET UP A PREFRONTAL CONVERGENCE ZONE ACROSS NORTHWEST IOWA THAT WILL FOCUS SOMETHING MORE INSTABILITY DRIVEN DURING THE AFTERNOON AHEAD OF THE FRONT...WHILE COLD FRONT IS MORE INERT BACK BETWEEN I29 AND THE JAMES RIVER. ENOUGH UNCERTAINTY THAT HAVE SPREAD OUT POPS A BIT MORE THAN WOULD NORMALLY DO. ALSO...THIS OPENS UP POTENTIAL FOR TEMPS TO GET QUITE WARM BETWEEN THE LOWER LEVEL MOISTURE SURGE AHEAD OF THE PREFRONTAL TROUGH AND THE ACTUAL COLD FRONT TO THE WEST...WHERE SOME 925 HPA TEMPS ONCE AGAIN BRING CHANCES FOR 70S BACK. WOULD CERTAINLY HAVE TO MONITOR THIS FOR POTENTIAL SEVERE STORMS GIVEN THE SHEAR WITH FAIRLY STRONG MID LEVEL FLOW...AND SOME POTENTIAL ENHANCEMENT TO THE LOWER LEVELS NEAR THE PREFRONTAL TROUGH. FAIRLY MINIMAL AGREEMENT IN LARGER SCALE TOWARD THE END OF THE WEEKEND...BUT TRENDING TOWARD A MORE COHERENT TROUGHINESS BY MONDAY. THIS WOULD AGREE SOMEWHAT WITH GFS IS ONLY SLOWED BY A 12-24H PERIOD. TEMPS COULD END UP SOMEWHAT COLDER ON MONDAY GIVEN A STRAIGHT ECMWF TYPE SOLUTION...LESS PROGRESSIVE THAN THE GFS. ECMWF WOULD SUGGEST THAT WAVE HANGING BACK IN THE SOUTHERN STREAM WOULD START TO PULL NORTHWARD AS SHARPER NORTHERN STREAM WAVE DIGS INTO THE NORTHERN PLAINS ON SUNDAY..SLOWING MID LEVEL BOUNDARY AND ENHANCING THREAT OF PRECIPITATION...ESPECIALLY ACROSS THE SOUTHEAST. NOT AS ENTHUSIASTIC ABOUT COOLING ALONG WITH PRECIP...WITH PERHAPS A LITTLE CHANGE TO SNOW OCCURRING AROUND SUNDAY NIGHT...UNLIKE THE GFS WHICH GOES ALL IN FOR A MIX OR CHANGE TOWARD THE END OF PRECIPITATION AS EARLY AS LATE SATURDAY NIGHT. FOR THE TIME... HAVE WEIGHTED ECMWF SOLUTION QUITE A BIT MORE. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 648 PM CDT MON APR 7 2014 VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. SCATTERED TO ISOLATED SHOWERS WILL TRACK SOUTH SOUTHEAST ACROSS THE FORECAST AREA THROUGH THE LATE EVENING HOURS. SOME ISOLATED TSRA WILL BE POSSIBLE...MAINLY BEFORE SUNSET. GUSTS TO 40 KT WILL ALSO BE POSSIBLE UNDER -TSRA...HOWEVER VFR CONDITIONS WILL PERSIST. ACTIVITY WILL WEAKEN AND GRADUALLY DISSIPATE IN COVERAGE LATE THIS EVENING. && .FIRE WEATHER... WILL BE ON THE LOOKOUT FOR A POTENTIAL FOR A CRITICAL FIRE WEATHER DAY ON WEDNESDAY. THIS LOOKS TO BE A CLASSIC MIXING DAY AHEAD OF APPROACHING FRONT WEDNESDAY NIGHT...WITH DEEP MIXING LIKELY DRIVING DEWPOINTS QUITE LOW. AT THIS TIME...LOOKING FOR AFTERNOON RELATIVE HUMIDITIES TO RANGE FROM 25 TO 30 PERCENT EAST...TO 15 TO 20 PERCENT MISSOURI AND JAMES VALLEYS. WINDS WILL BE MARGINAL FOR PRODUCING CRITICAL FIRE BEHAVIOR...AND WILL BE REEVALUATING FOR A POSSIBLE FIRE WEATHER WATCH ON MID SHIFT. THURSDAY WILL ALSO BRING POTENTIAL FOR A VERY HIGH FIRE DANGER WITH AGAIN SOME MARGINALLY STRONG NORTHWEST WINDS...AND DRY DEWPOINTS KNOCKING AFTERNOON HUMIDITIES TO 25 TO 30 PERCENT MANY AREAS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM... LONG TERM...CHAPMAN AVIATION... FIRE WEATHER...CHAPMAN
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1259 PM CDT SUN APR 6 2014 .AVIATION... /18Z TAFS/ A combination of MVFR and IFR conditions continue across the terminals early this afternoon. Light rain showers are currently affecting the KABI terminal with some fog reducing visibilities to 3 to 4SM at KJCT and KBBD. Should see an improvement in both CIGS and visibilities by late afternoon with VFR/MVFR dominating. Some scattered showers will be possible primarily across the KABI and KSJT terminals through late afternoon. Carrying VCSH for now due to coverage uncertainty. MVFR/IFR CIGS expected to return late tonight into Monday morning, with VFR returning by afternoon. && .PREV DISCUSSION... /ISSUED 1059 AM CDT Sun Apr 6 2014/ UPDATE... The forecast was updated to increase POPs slightly across central and western counties this afternoon and to lower max temps a few degrees. Spotty light rain showers continue across mainly the Big Country late this morning. Showers and isolated thunderstorms were also entering extreme western portions of the Big Country and Concho Valley. Latest HRRR/3km WRF data shows this area of precipitation moving east across the area this afternoon. Mid level lapse rates (700-500mb) will increase to 7 to 8 DEG C/KM this afternoon, so will continue to keep a mention of thunderstorms in the forecast. Severe weather is not anticipated but a few of the stronger cells will be capable of producing small hail and gusty winds. Abundant cloud cover and precip will hold temperatures down across much of the area this afternoon with highs mainly in the upper 50s and lower 60s. Some drier air will enter southwest counties later this afternoon with some partial clearing expected. This should allow temperatures to reach the upper 60s and lower 70s across this area. PREV DISCUSSION... /ISSUED 612 AM CDT SUN APR 6 2014/ AVIATION... /12Z TAFS/ Widespread stratus will continue across West Central Texas through much of the next 24 hours. As a result, MVFR/IFR CIGS are expected at the terminals. There may be some improvement this afternoon at the KSOA and KSJT terminals due to low level westerly flow bringing low level dry air, and have gone with VFR conditions. Low clouds will return to much of the area late tonight. An upper level trough will bring increasing lift, resulting in scattered showers and isolated thunderstorms. Have continued VCSH at the KABI and KBBD terminals for today. PREV DISCUSSION... /ISSUED 351 AM CDT SUN APR 6 2014/ SHORT TERM... (Today and Tonight) Latest satellite imagery showing low clouds have spread north across all of West Central Texas. Aloft, upper level trough was located over the southwest U.S., with trough axis along the Arizona/New Mexico border. Ahead of the trough, weak large-scale ascent was over Texas as evident by a few light showers over the eastern half of our area. For today, as the upper level system moves east into the Southern Plains, mid and upper level forcing will increase across West Central Texas. Showers will become more widespread especially across the eastern half of the area. The HRRR convective allowing model indicates activity picking up over the Heartland and Northwest Hill Country during the morning hours(after 10Z). Have the highest POPS (likely to high end chance) across the eastern 1/3 of the area, decreasing to slight chance southwest of a Sterling City to San Angelo to Junction line as forcing will be much weaker. The mid level lapse rates will increase to 7 to 8 DEG C/KM later today so isolated thunderstorms will be possible. A couple of storms will have the potential to produce small hail, gusty winds and dangerous cloud to ground lightning. Rainfall amounts will average 1/4 to 1/2 of an inch, with the higher amounts across eastern 1/3 of the area. A few areas like the Northern Edwards Plateau will not even receive a tenth of an inch. Highs will be in the 60s to lower 70s across the western Concho Valley and along the I-10 corridor. For tonight, the best large-scale ascent will be located east of West Central Texas. Will keep the slight chance POPS going across mainly the Big Country, otherwise going with a dry forecast. Lows will be in the 40s. LONG TERM... (Monday through Saturday) On Monday, we may have some lingering showers around the area as a shortwave currently moving southeast into the Pacific Northwest out of southwestern Canada will move through the main upper level trough before it moves east of the area. Have kept the lower end slight chance PoPs going for the area. If any precipitation occurs, the main mode would likely be showers again, but an isolated thunderstorm or two would still be possible as cold temperatures associated with the upper level low will help increase lapse rates aloft. In addition, northerly flow at the surface will bring in drier air resulting in an inverted V soundings for southern areas, which could lead to gusty winds at the surface underneath any showers, virga, or thunderstorms. Rainfall amounts are expected to be light with this activity. Tuesday through the middle of the week, we can expect dry weather, and warming temperatures. Dry northwest flow aloft Tuesday into Wednesday will be replaced by low amplitude ridging, or zonal flow Thursday and Friday. Gulf moisture will move back into the area by the second half of the week as well with persistent southerly low level flow. After Friday, models disagree on timing and strength of another possible trough moving through the area, so have made very minimal changes to the forecast beyond Day 4. FIRE WEATHER... With cooler temperatures and a chance for precipitation through Monday for most of the area, fire weather conditions will not be a concern for most of the area. However, by Tuesday, rain chances move out, and temperatures begin to warm back up. Elevated to near critical conditions will be possible Tuesday through the end of next week, and especially on Wednesday and Thursday for areas west of an Abilene to Sonora line, as southerly winds pick up to 15 to 20 mph, and relative humidity values fall to 15 to 20 percent. && .PRELIMINARY POINT TEMPS/POPS... Abilene 60 45 70 41 74 / 50 20 20 10 0 San Angelo 67 44 72 41 77 / 30 10 20 10 0 Junction 68 43 73 39 79 / 20 10 20 20 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1233 PM CDT SUN APR 6 2014 .AVIATION... RADAR AND LIGHTNING DATA SHOW STORMS ARE ON THE DOWN TREND AND GUIDANCE SHOWS LARGE SCALE LIFT SHOULD DECREASE THIS AFTERNOON AS WELL. HAVE TIMED OUT CURRENT STORMS BY 19Z AND THINK TAF SITES CAN EXPECT ONLY SHOWERS THROUGH REST OF AFTERNOON/EVENING. CEILINGS WILL REMAIN PROBLEMATIC SINCE THERE ARE A NUMBER OF SITES REPORTING IFR AND LIFR BUT MANY METROPLEX SITES REMAIN VFR. I HAVE LITTLE CONFIDENCE THAT VFR CONDITIONS WILL CONTINUE SO HAVE KEPT FORECAST LOWER. WITH ALL THE MOISTURE ON THE GROUND...EXPECT BR AND IFR CIGS TO OCCUR BY MID EVENING AND LAST THROUGH SUNRISE...TRENDING UP DURING THE MORNING. GUIDANCE CONTINUES TO INDICATE INSTABILITY DURING THE AFTERNOON MONDAY SO HAVE ADDED VCSH AND WE WILL HAVE TO REFINE THE TSRA THREAT FOR THAT PERIOD. 84 && .UPDATE... 12Z FWD SOUNDING SHOWS MUCAPE ABOUT DOUBLE WHAT WAS FORECAST... NEAR 700 J/KG. LATEST RAP NOW INDICATING AS MUCH AS 1000 J/KG OF MUCAPE ACROSS THE SOUTHEAST ZONES THIS MORNING. EARLY RADAR TRENDS CONFIRM AMPLE INSTABILITY IS AVAILABLE WITH ALREADY ONE SEVERE STORM IN BOSQUE COUNTY THIS MORNING. HAVE UPDATED THE FORECAST TO SHOW THE NEW WATCH AND MENTION A THREAT FOR HAIL IN THE STRONGEST STORMS...PERHAPS UP TO QUARTER SIZE IN OTHER PRODUCTS. AGAIN STRONGEST STORMS AND BEST COVERAGE OF STORMS WILL BE THIS MORNING...AND NO CHANGE WITH THAT THINKING. TR.92 && .PREV DISCUSSION... /ISSUED 429 AM CDT SUN APR 6 2014/ A STRONG UPPER LEVEL TROUGH IS NOW ENCROACHING UPON THE REGION AND AREA VWPS SHOW 850MB WINDS HAVE BECOME SOUTHERLY AND INCREASED TO 30KT DURING THE NIGHT. THIS WILL RESULT IN STRONG THETA-E ADVECTION AS RICH GULF MOISTURE IS LIFTED NORTHWARD AND OVER A QUASI-STATIONARY FRONTAL BOUNDARY LOCATED ALONG THE TEXAS COAST. NUMEROUS SHOWERS AND A FEW THUNDERSTORMS ARE EXPECTED OVER NORTH TEXAS TODAY AS STRONG ISENTROPIC LIFT BECOMES THE CATALYST FOR PARCELS TO ACHIEVE THEIR LFC. THE INTRODUCTION OF HIGH THETA-E AIR COINCIDENT WITH STEEPENING UPPER LEVEL LAPSE RATES AHEAD OF THE TROUGH WILL YIELD 200-600 J/KG OF CAPE WITH PARCELS LIFTED NEAR 850MB. THE HIGHEST MUCAPE WILL BE ACROSS THE SOUTHEAST HALF OF THE AREA WHERE COVERAGE OF STORMS SHOULD BE GREATEST TODAY. THUNDERSTORMS WILL BE MOST NUMEROUS DURING THE MORNING HOURS BEFORE INSTABILITY GETS EXHAUSTED...WITH PRIMARILY SHOWERS EXPECTED DURING THE AFTERNOON AND EVENING HOURS. A DRY SLOT WILL ROTATE IN FROM THE SOUTHWEST WHICH WILL HELP END MOST OF THE CONVECTION FROM SOUTHWEST TO NORTHEAST DURING THE AFTERNOON HOURS. HOWEVER...WRAP-AROUND RAIN MAY WORK BACK INTO THE NORTHERN ZONES THIS EVENING AS A TROWAL DEVELOPS ON THE BACKSIDE OF A MID-LEVEL LOW THAT TRACKS ALONG THE RED RIVER. ALL RAIN SHOULD COME TO AN END BY MIDNIGHT. RAINFALL WILL AVERAGE 1/4 TO 1/2 INCH OVER THE AREA TODAY...WITH ISOLATED AMOUNTS OVER AN INCH WHERE THUNDERSTORMS CAN LOCALLY ENHANCE TOTALS. OTHERWISE IT WILL BE UNSEASONABLY COOL TODAY WITH HIGHS ONLY IN THE 50S...WITH TEMPS DROPPING INTO THE 40S DURING PERIODS OF RAIN THIS MORNING. THE UPPER LEVEL TROUGH WILL MOVE TO OUR EAST TOMORROW PUTTING NORTH TEXAS IN A REGION OF STRONG ISENTROPIC DOWNGLIDE. THIS DOWNGLIDE SHOULD HELP ERODE THE CLOUD COVER...WITH BREAKS IN THE OVERCAST EXPECTED BY NOON. USUALLY ON THE BACK SIDE OF THESE TROUGHS WE ARE IN REGION OF STRONG SUBSIDENCE. HOWEVER MODELS ARE CONSISTENT IN DROPPING A STRONG POCKET OF POTENTIAL VORTICITY DOWN THROUGH THE PLAINS AND INTO NORTH TEXAS BY THE EVENING HOURS. AHEAD OF THIS FEATURE...HEIGHT FALLS AND COOLING TEMPS ALOFT WILL OCCUR...ALL SIGNS THAT FAIRLY STRONG SYNOPTIC SCALE ASCENT IS FORECAST. 500MB TEMPS SHOULD DROP TO NEAR -25C...WHICH IS EXTRAORDINARILY COLD FOR APRIL. THE COLD AIR ALOFT AND TEMPERATURES WARMING INTO THE 60S WILL YIELD 500-1000J/KG OF SURFACE BASED CAPE. EXPECT SCATTERED CONVECTION TO DEVELOP OVER THE REGION MONDAY AFTERNOON AND HEAD SOUTHEAST THROUGH THE EVENING HOURS. HI-RES WRF MODELS CONTINUE TO BE MOST AGGRESSIVE WITH CONVECTION...AND HAVE BUMPED POPS UP TO 30 PERCENT IN MOST AREAS AS A RESULT. WHILE CAPE AND DEEP LAYER SHEAR LOOK A LITTLE TOO LOW TO SUPPORT SUPERCELL CONVECTIVE MODES AT THIS TIME...THE EXTREMELY COLD AIR ALOFT WITH FREEZING LEVELS DROPPING TO 8000FT WOULD SUPPORT A SMALL HAIL THREAT. HOWEVER IF MORE SUNSHINE DID OCCUR MONDAY...THE STRONGER HEATING WOULD INCREASE THE SUPERCELL/HAIL THREAT. FURTHERMORE BECAUSE WE WILL BE LOCATED ON THE WEST SIDE OF THE TROUGH MONDAY...ANY SUPERCELL STORMS WOULD ACTUALLY BE LEFT MOVING OR ANTI-CYCLONIC. RAPID CLEARING WILL OCCUR MONDAY NIGHT AS THE UPPER LEVEL ENERGY MOVES EAST OF THE REGION...AND LOWS WILL DROP INTO THE 40S BY TUESDAY MORNING. SUNNY SKIES WILL RESULT IN STEEP LOW LEVEL LAPSE RATES AND THIS SHOULD MIX STRONG NORTHERLY WINDS DOWN TO THE SURFACE TUESDAY. FIRE DANGER WILL BE LIMITED BY COOLISH TEMPS WITH HIGHS ONLY NEAR 70 DEGREES...AND WHAT SHOULD BE MOIST FUELS FROM THE FORECASTED RAINFALL. GOOD RADIATIONAL COOLING IS EXPECTED TUESDAY NIGHT AS WINDS DIE OFF AND THE SURFACE HIGH TRANSLATES OVER NORTH TEXAS. LOWS WILL FALL INTO THE UPPER 30S EAST TO UPPER 40S WEST. WEDNESDAY LOOKS SUNNY AND VERY NICE WITH HIGHS WARMING TO NEAR 80. SUNNY SKIES CONTINUE INTO THURSDAY AND FRIDAY WITH HIGHS WARMING INTO THE 80S. BREEZY SOUTH WINDS WILL RETURN THURSDAY AS WELL...BRINGING ELEVATED FIRE DANGER TO THE REGION. EXTENDED MODEL GUIDANCE IS NOT IN GOOD AGREEMENT WITH THE NEXT UPPER LEVEL SYSTEM. THE GFS IS THE FASTEST/STRONGEST AND BRINGS IT THROUGH SATURDAY NIGHT...WHILE THE ECMWF WEAKENS IT AND BRINGS IT THROUGH SUNDAY. THE PROSPECTS FOR SIGNIFICANT RAIN OR SEVERE WEATHER WILL BE TEMPERED BY A STRONG CAP OVER THE REGION...AND LIMITED MOISTURE RETURN DUE TO THE PRESENCE OF A SURFACE HIGH THAT SITS OVER THE GULF MID-LATE WEEK. WILL SIDE WITH THE ECMWF MORE THAN THE GFS...AND BRING LOW POPS INTO THE AREA SATURDAY NIGHT. BOTH MODELS ADVERTISE A STRONG FRONT BY SUNDAY NIGHT...WITH SOME RAIN CHANCES ALONG AND BEHIND IT. TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 54 48 65 44 71 / 100 40 30 20 0 WACO, TX 57 48 67 46 72 / 90 20 30 20 0 PARIS, TX 54 47 62 45 66 / 100 60 30 20 0 DENTON, TX 54 46 64 43 70 / 100 40 30 20 0 MCKINNEY, TX 54 47 64 44 68 / 100 40 30 20 0 DALLAS, TX 54 48 65 45 71 / 100 40 30 20 0 TERRELL, TX 54 48 64 44 69 / 100 30 30 20 0 CORSICANA, TX 56 49 65 45 69 / 100 20 20 20 0 TEMPLE, TX 59 47 68 45 73 / 80 20 20 20 0 MINERAL WELLS, TX 54 45 67 42 73 / 90 30 30 10 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1059 AM CDT Sun Apr 6 2014 .UPDATE... The forecast was updated to increase POPs slightly across central and western counties this afternoon and to lower max temps a few degrees. Spotty light rain showers continue across mainly the Big Country late this morning. Showers and isolated thunderstorms were also entering extreme western portions of the Big Country and Concho Valley. Latest HRRR/3km WRF data shows this area of precipitation moving east across the area this afternoon. Mid level lapse rates (700-500mb) will increase to 7 to 8 DEG C/KM this afternoon, so will continue to keep a mention of thunderstorms in the forecast. Severe weather is not anticipated but a few of the stronger cells will be capable of producing small hail and gusty winds. Abundant cloud cover and precip will hold temperatures down across much of the area this afternoon with highs mainly in the upper 50s and lower 60s. Some drier air will enter southwest counties later this afternoon with some partial clearing expected. This should allow temperatures to reach the upper 60s and lower 70s across this area. && .PREV DISCUSSION... /ISSUED 612 AM CDT SUN APR 6 2014/ AVIATION... /12Z TAFS/ Widespread stratus will continue across West Central Texas through much of the next 24 hours. As a result, MVFR/IFR CIGS are expected at the terminals. There may be some improvement this afternoon at the KSOA and KSJT terminals due to low level westerly flow bringing low level dry air, and have gone with VFR conditions. Low clouds will return to much of the area late tonight. An upper level trough will bring increasing lift, resulting in scattered showers and isolated thunderstorms. Have continued VCSH at the KABI and KBBD terminals for today. PREV DISCUSSION... /ISSUED 351 AM CDT SUN APR 6 2014/ SHORT TERM... (Today and Tonight) Latest satellite imagery showing low clouds have spread north across all of West Central Texas. Aloft, upper level trough was located over the southwest U.S., with trough axis along the Arizona/New Mexico border. Ahead of the trough, weak large-scale ascent was over Texas as evident by a few light showers over the eastern half of our area. For today, as the upper level system moves east into the Southern Plains, mid and upper level forcing will increase across West Central Texas. Showers will become more widespread especially across the eastern half of the area. The HRRR convective allowing model indicates activity picking up over the Heartland and Northwest Hill Country during the morning hours(after 10Z). Have the highest POPS (likely to high end chance) across the eastern 1/3 of the area, decreasing to slight chance southwest of a Sterling City to San Angelo to Junction line as forcing will be much weaker. The mid level lapse rates will increase to 7 to 8 DEG C/KM later today so isolated thunderstorms will be possible. A couple of storms will have the potential to produce small hail, gusty winds and dangerous cloud to ground lightning. Rainfall amounts will average 1/4 to 1/2 of an inch, with the higher amounts across eastern 1/3 of the area. A few areas like the Northern Edwards Plateau will not even receive a tenth of an inch. Highs will be in the 60s to lower 70s across the western Concho Valley and along the I-10 corridor. For tonight, the best large-scale ascent will be located east of West Central Texas. Will keep the slight chance POPS going across mainly the Big Country, otherwise going with a dry forecast. Lows will be in the 40s. LONG TERM... (Monday through Saturday) On Monday, we may have some lingering showers around the area as a shortwave currently moving southeast into the Pacific Northwest out of southwestern Canada will move through the main upper level trough before it moves east of the area. Have kept the lower end slight chance PoPs going for the area. If any precipitation occurs, the main mode would likely be showers again, but an isolated thunderstorm or two would still be possible as cold temperatures associated with the upper level low will help increase lapse rates aloft. In addition, northerly flow at the surface will bring in drier air resulting in an inverted V soundings for southern areas, which could lead to gusty winds at the surface underneath any showers, virga, or thunderstorms. Rainfall amounts are expected to be light with this activity. Tuesday through the middle of the week, we can expect dry weather, and warming temperatures. Dry northwest flow aloft Tuesday into Wednesday will be replaced by low amplitude ridging, or zonal flow Thursday and Friday. Gulf moisture will move back into the area by the second half of the week as well with persistent southerly low level flow. After Friday, models disagree on timing and strength of another possible trough moving through the area, so have made very minimal changes to the forecast beyond Day 4. FIRE WEATHER... With cooler temperatures and a chance for precipitation through Monday for most of the area, fire weather conditions will not be a concern for most of the area. However, by Tuesday, rain chances move out, and temperatures begin to warm back up. Elevated to near critical conditions will be possible Tuesday through the end of next week, and especially on Wednesday and Thursday for areas west of an Abilene to Sonora line, as southerly winds pick up to 15 to 20 mph, and relative humidity values fall to 15 to 20 percent. && .PRELIMINARY POINT TEMPS/POPS... Abilene 60 46 70 41 73 / 50 20 20 5 0 San Angelo 67 46 72 41 77 / 30 10 20 0 0 Junction 68 46 73 39 78 / 20 10 20 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
659 AM CDT SUN APR 6 2014 .UPDATE... 12Z FWD SOUNDING SHOWS MUCAPE ABOUT DOUBLE WHAT WAS FORECAST... NEAR 700 J/KG. LATEST RAP NOW INDICATING AS MUCH AS 1000 J/KG OF MUCAPE ACROSS THE SOUTHEAST ZONES THIS MORNING. EARLY RADAR TRENDS CONFIRM AMPLE INSTABILITY IS AVAILABLE WITH ALREADY ONE SEVERE STORM IN BOSQUE COUNTY THIS MORNING. HAVE UPDATED THE FORECAST TO SHOW THE NEW WATCH AND MENTION A THREAT FOR HAIL IN THE STRONGEST STORMS...PERHAPS UP TO QUARTER SIZE IN OTHER PRODUCTS. AGAIN STRONGEST STORMS AND BEST COVERAGE OF STORMS WILL BE THIS MORNING...AND NO CHANGE WITH THAT THINKING. TR.92 && .AVIATION... PERIODS OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY AND WILL PREVAIL VCTS THROUGH THE MORNING HOURS. WILL HANDLE EACH BAND OF THUNDERSTORMS WITH A TEMPO TO TRY TO PIN DOWN THE BEST TIMING OF ACTIVITY. LAPSE RATES BECOME LESS STEEP THIS AFTERNOON AND WILL JUST MENTION -RA/SHRA DURING THE AFTERNOON HOURS. WACO WILL LIKELY RECEIVE A BREAK IN THE RAIN THIS AFTERNOON BEFORE ADDITIONAL SHOWERS MOVE IN FROM THE WEST AS THE MAIN FORCING ALOFT REACHES THE REGION. CIGS WILL DETERIORATE THROUGHOUT THE MORNING WITH IFR EXPECTED FOR MUCH OF THE PERIOD AFTER 14-15Z. HAMPSHIRE && .PREV DISCUSSION... /ISSUED 429 AM CDT SUN APR 6 2014/ A STRONG UPPER LEVEL TROUGH IS NOW ENCROACHING UPON THE REGION AND AREA VWPS SHOW 850MB WINDS HAVE BECOME SOUTHERLY AND INCREASED TO 30KT DURING THE NIGHT. THIS WILL RESULT IN STRONG THETA-E ADVECTION AS RICH GULF MOISTURE IS LIFTED NORTHWARD AND OVER A QUASI-STATIONARY FRONTAL BOUNDARY LOCATED ALONG THE TEXAS COAST. NUMEROUS SHOWERS AND A FEW THUNDERSTORMS ARE EXPECTED OVER NORTH TEXAS TODAY AS STRONG ISENTROPIC LIFT BECOMES THE CATALYST FOR PARCELS TO ACHIEVE THEIR LFC. THE INTRODUCTION OF HIGH THETA-E AIR COINCIDENT WITH STEEPENING UPPER LEVEL LAPSE RATES AHEAD OF THE TROUGH WILL YIELD 200-600 J/KG OF CAPE WITH PARCELS LIFTED NEAR 850MB. THE HIGHEST MUCAPE WILL BE ACROSS THE SOUTHEAST HALF OF THE AREA WHERE COVERAGE OF STORMS SHOULD BE GREATEST TODAY. THUNDERSTORMS WILL BE MOST NUMEROUS DURING THE MORNING HOURS BEFORE INSTABILITY GETS EXHAUSTED...WITH PRIMARILY SHOWERS EXPECTED DURING THE AFTERNOON AND EVENING HOURS. A DRY SLOT WILL ROTATE IN FROM THE SOUTHWEST WHICH WILL HELP END MOST OF THE CONVECTION FROM SOUTHWEST TO NORTHEAST DURING THE AFTERNOON HOURS. HOWEVER...WRAP-AROUND RAIN MAY WORK BACK INTO THE NORTHERN ZONES THIS EVENING AS A TROWAL DEVELOPS ON THE BACKSIDE OF A MID-LEVEL LOW THAT TRACKS ALONG THE RED RIVER. ALL RAIN SHOULD COME TO AN END BY MIDNIGHT. RAINFALL WILL AVERAGE 1/4 TO 1/2 INCH OVER THE AREA TODAY...WITH ISOLATED AMOUNTS OVER AN INCH WHERE THUNDERSTORMS CAN LOCALLY ENHANCE TOTALS. OTHERWISE IT WILL BE UNSEASONABLY COOL TODAY WITH HIGHS ONLY IN THE 50S...WITH TEMPS DROPPING INTO THE 40S DURING PERIODS OF RAIN THIS MORNING. THE UPPER LEVEL TROUGH WILL MOVE TO OUR EAST TOMORROW PUTTING NORTH TEXAS IN A REGION OF STRONG ISENTROPIC DOWNGLIDE. THIS DOWNGLIDE SHOULD HELP ERODE THE CLOUD COVER...WITH BREAKS IN THE OVERCAST EXPECTED BY NOON. USUALLY ON THE BACK SIDE OF THESE TROUGHS WE ARE IN REGION OF STRONG SUBSIDENCE. HOWEVER MODELS ARE CONSISTENT IN DROPPING A STRONG POCKET OF POTENTIAL VORTICITY DOWN THROUGH THE PLAINS AND INTO NORTH TEXAS BY THE EVENING HOURS. AHEAD OF THIS FEATURE...HEIGHT FALLS AND COOLING TEMPS ALOFT WILL OCCUR...ALL SIGNS THAT FAIRLY STRONG SYNOPTIC SCALE ASCENT IS FORECAST. 500MB TEMPS SHOULD DROP TO NEAR -25C...WHICH IS EXTRAORDINARILY COLD FOR APRIL. THE COLD AIR ALOFT AND TEMPERATURES WARMING INTO THE 60S WILL YIELD 500-1000J/KG OF SURFACE BASED CAPE. EXPECT SCATTERED CONVECTION TO DEVELOP OVER THE REGION MONDAY AFTERNOON AND HEAD SOUTHEAST THROUGH THE EVENING HOURS. HI-RES WRF MODELS CONTINUE TO BE MOST AGGRESSIVE WITH CONVECTION...AND HAVE BUMPED POPS UP TO 30 PERCENT IN MOST AREAS AS A RESULT. WHILE CAPE AND DEEP LAYER SHEAR LOOK A LITTLE TOO LOW TO SUPPORT SUPERCELL CONVECTIVE MODES AT THIS TIME...THE EXTREMELY COLD AIR ALOFT WITH FREEZING LEVELS DROPPING TO 8000FT WOULD SUPPORT A SMALL HAIL THREAT. HOWEVER IF MORE SUNSHINE DID OCCUR MONDAY...THE STRONGER HEATING WOULD INCREASE THE SUPERCELL/HAIL THREAT. FURTHERMORE BECAUSE WE WILL BE LOCATED ON THE WEST SIDE OF THE TROUGH MONDAY...ANY SUPERCELL STORMS WOULD ACTUALLY BE LEFT MOVING OR ANTI-CYCLONIC. RAPID CLEARING WILL OCCUR MONDAY NIGHT AS THE UPPER LEVEL ENERGY MOVES EAST OF THE REGION...AND LOWS WILL DROP INTO THE 40S BY TUESDAY MORNING. SUNNY SKIES WILL RESULT IN STEEP LOW LEVEL LAPSE RATES AND THIS SHOULD MIX STRONG NORTHERLY WINDS DOWN TO THE SURFACE TUESDAY. FIRE DANGER WILL BE LIMITED BY COOLISH TEMPS WITH HIGHS ONLY NEAR 70 DEGREES...AND WHAT SHOULD BE MOIST FUELS FROM THE FORECASTED RAINFALL. GOOD RADIATIONAL COOLING IS EXPECTED TUESDAY NIGHT AS WINDS DIE OFF AND THE SURFACE HIGH TRANSLATES OVER NORTH TEXAS. LOWS WILL FALL INTO THE UPPER 30S EAST TO UPPER 40S WEST. WEDNESDAY LOOKS SUNNY AND VERY NICE WITH HIGHS WARMING TO NEAR 80. SUNNY SKIES CONTINUE INTO THURSDAY AND FRIDAY WITH HIGHS WARMING INTO THE 80S. BREEZY SOUTH WINDS WILL RETURN THURSDAY AS WELL...BRINGING ELEVATED FIRE DANGER TO THE REGION. EXTENDED MODEL GUIDANCE IS NOT IN GOOD AGREEMENT WITH THE NEXT UPPER LEVEL SYSTEM. THE GFS IS THE FASTEST/STRONGEST AND BRINGS IT THROUGH SATURDAY NIGHT...WHILE THE ECMWF WEAKENS IT AND BRINGS IT THROUGH SUNDAY. THE PROSPECTS FOR SIGNIFICANT RAIN OR SEVERE WEATHER WILL BE TEMPERED BY A STRONG CAP OVER THE REGION...AND LIMITED MOISTURE RETURN DUE TO THE PRESENCE OF A SURFACE HIGH THAT SITS OVER THE GULF MID-LATE WEEK. WILL SIDE WITH THE ECMWF MORE THAN THE GFS...AND BRING LOW POPS INTO THE AREA SATURDAY NIGHT. BOTH MODELS ADVERTISE A STRONG FRONT BY SUNDAY NIGHT...WITH SOME RAIN CHANCES ALONG AND BEHIND IT. TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 54 48 65 44 71 / 100 40 30 20 0 WACO, TX 57 48 67 46 72 / 90 20 30 20 0 PARIS, TX 54 47 62 45 66 / 100 60 30 20 0 DENTON, TX 54 46 64 43 70 / 100 40 30 20 0 MCKINNEY, TX 54 47 64 44 68 / 100 40 30 20 0 DALLAS, TX 54 48 65 45 71 / 100 40 30 20 0 TERRELL, TX 54 48 64 44 69 / 100 30 30 20 0 CORSICANA, TX 56 49 65 45 69 / 100 20 20 20 0 TEMPLE, TX 59 47 68 45 73 / 80 20 20 20 0 MINERAL WELLS, TX 54 45 67 42 73 / 90 30 30 10 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
612 AM CDT SUN APR 6 2014 .AVIATION... /12Z TAFS/ Widespread stratus will continue across West Central Texas through much of the next 24 hours. As a result, MVFR/IFR CIGS are expected at the terminals. There may be some improvement this afternoon at the KSOA and KSJT terminals due to low level westerly flow bringing low level dry air, and have gone with VFR conditions. Low clouds will return to much of the area late tonight. An upper level trough will bring increasing lift, resulting in scattered showers and isolated thunderstorms. Have continued VCSH at the KABI and KBBD terminals for today. && .PREV DISCUSSION... /ISSUED 351 AM CDT SUN APR 6 2014/ SHORT TERM... (Today and Tonight) Latest satellite imagery showing low clouds have spread north across all of West Central Texas. Aloft, upper level trough was located over the southwest U.S., with trough axis along the Arizona/New Mexico border. Ahead of the trough, weak large-scale ascent was over Texas as evident by a few light showers over the eastern half of our area. For today, as the upper level system moves east into the Southern Plains, mid and upper level forcing will increase across West Central Texas. Showers will become more widespread especially across the eastern half of the area. The HRRR convective allowing model indicates activity picking up over the Heartland and Northwest Hill Country during the morning hours(after 10Z). Have the highest POPS (likely to high end chance) across the eastern 1/3 of the area, decreasing to slight chance southwest of a Sterling City to San Angelo to Junction line as forcing will be much weaker. The mid level lapse rates will increase to 7 to 8 DEG C/KM later today so isolated thunderstorms will be possible. A couple of storms will have the potential to produce small hail, gusty winds and dangerous cloud to ground lightning. Rainfall amounts will average 1/4 to 1/2 of an inch, with the higher amounts across eastern 1/3 of the area. A few areas like the Northern Edwards Plateau will not even receive a tenth of an inch. Highs will be in the 60s to lower 70s across the western Concho Valley and along the I-10 corridor. For tonight, the best large-scale ascent will be located east of West Central Texas. Will keep the slight chance POPS going across mainly the Big Country, otherwise going with a dry forecast. Lows will be in the 40s. LONG TERM... (Monday through Saturday) On Monday, we may have some lingering showers around the area as a shortwave currently moving southeast into the Pacific Northwest out of southwestern Canada will move through the main upper level trough before it moves east of the area. Have kept the lower end slight chance PoPs going for the area. If any precipitation occurs, the main mode would likely be showers again, but an isolated thunderstorm or two would still be possible as cold temperatures associated with the upper level low will help increase lapse rates aloft. In addition, northerly flow at the surface will bring in drier air resulting in an inverted V soundings for southern areas, which could lead to gusty winds at the surface underneath any showers, virga, or thunderstorms. Rainfall amounts are expected to be light with this activity. Tuesday through the middle of the week, we can expect dry weather, and warming temperatures. Dry northwest flow aloft Tuesday into Wednesday will be replaced by low amplitude ridging, or zonal flow Thursday and Friday. Gulf moisture will move back into the area by the second half of the week as well with persistent southerly low level flow. After Friday, models disagree on timing and strength of another possible trough moving through the area, so have made very minimal changes to the forecast beyond Day 4. FIRE WEATHER... With cooler temperatures and a chance for precipitation through Monday for most of the area, fire weather conditions will not be a concern for most of the area. However, by Tuesday, rain chances move out, and temperatures begin to warm back up. Elevated to near critical conditions will be possible Tuesday through the end of next week, and especially on Wednesday and Thursday for areas west of an Abilene to Sonora line, as southerly winds pick up to 15 to 20 mph, and relative humidity values fall to 15 to 20 percent. && .PRELIMINARY POINT TEMPS/POPS... Abilene 60 46 70 41 73 / 40 20 20 5 0 San Angelo 69 46 72 41 77 / 20 10 20 0 0 Junction 71 46 73 39 78 / 20 10 20 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
351 AM CDT SUN APR 6 2014 .SHORT TERM... (Today and Tonight) Latest satellite imagery showing low clouds have spread north across all of West Central Texas. Aloft, upper level trough was located over the southwest U.S., with trough axis along the Arizona/New Mexico border. Ahead of the trough, weak large-scale ascent was over Texas as evident by a few light showers over the eastern half of our area. For today, as the upper level system moves east into the Southern Plains, mid and upper level forcing will increase across West Central Texas. Showers will become more widespread especially across the eastern half of the area. The HRRR convective allowing model indicates activity picking up over the Heartland and Northwest Hill Country during the morning hours(after 10Z). Have the highest POPS (likely to high end chance) across the eastern 1/3 of the area, decreasing to slight chance southwest of a Sterling City to San Angelo to Junction line as forcing will be much weaker. The mid level lapse rates will increase to 7 to 8 DEG C/KM later today so isolated thunderstorms will be possible. A couple of storms will have the potential to produce small hail, gusty winds and dangerous cloud to ground lightning. Rainfall amounts will average 1/4 to 1/2 of an inch, with the higher amounts across eastern 1/3 of the area. A few areas like the Northern Edwards Plateau will not even receive a tenth of an inch. Highs will be in the 60s to lower 70s across the western Concho Valley and along the I-10 corridor. For tonight, the best large-scale ascent will be located east of West Central Texas. Will keep the slight chance POPS going across mainly the Big Country, otherwise going with a dry forecast. Lows will be in the 40s. .LONG TERM... (Monday through Saturday) On Monday, we may have some lingering showers around the area as a shortwave currently moving southeast into the Pacific Northwest out of southwestern Canada will move through the main upper level trough before it moves east of the area. Have kept the lower end slight chance PoPs going for the area. If any precipitation occurs, the main mode would likely be showers again, but an isolated thunderstorm or two would still be possible as cold temperatures associated with the upper level low will help increase lapse rates aloft. In addition, northerly flow at the surface will bring in drier air resulting in an inverted V soundings for southern areas, which could lead to gusty winds at the surface underneath any showers, virga, or thunderstorms. Rainfall amounts are expected to be light with this activity. Tuesday through the middle of the week, we can expect dry weather, and warming temperatures. Dry northwest flow aloft Tuesday into Wednesday will be replaced by low amplitude ridging, or zonal flow Thursday and Friday. Gulf moisture will move back into the area by the second half of the week as well with persistent southerly low level flow. After Friday, models disagree on timing and strength of another possible trough moving through the area, so have made very minimal changes to the forecast beyond Day 4. && .FIRE WEATHER... With cooler temperatures and a chance for precipitation through Monday for most of the area, fire weather conditions will not be a concern for most of the area. However, by Tuesday, rain chances move out, and temperatures begin to warm back up. Elevated to near critical conditions will be possible Tuesday through the end of next week, and especially on Wednesday and Thursday for areas west of an Abilene to Sonora line, as southerly winds pick up to 15 to 20 mph, and relative humidity values fall to 15 to 20 percent. && .PRELIMINARY POINT TEMPS/POPS... Abilene 60 46 70 41 73 / 40 20 20 5 0 San Angelo 69 46 72 41 77 / 20 10 20 0 0 Junction 71 46 73 39 78 / 20 10 20 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21/20
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1152 PM CDT SAT APR 5 2014 .AVIATION... MESSY UPPER PATTERN ALONG WITH WARM FRONT APPROACHING THE COAST TOWARD MORNING SHOULD BRING AN INCREASE IN PRECIP COVERAGE AFTER 9Z. LATEST 00Z GUIDANCE BRINGS WARM SECTOR FURTHER INLAND THAN EARLIER RUNS. ADJUSTED WINDS ACCORDINGLY IN UPCOMING TAFS. OVERALL CONFIDENCE ON TIMING/POSITIONING AND AREAL PRECIP COVERAGE REMAINS QUITE LOW. THINK HRRR HAS HANDLED SHORT TERM TRENDS BEST AND ANTICIPATE SOME DEVELOPMENT OFFSHORE IN THE NEXT SEVERAL HOURS...BUT OVERALL BEST COVERAGE ACROSS N/NE PARTS OF SE TX ON SUNDAY. OIL RIGS OFFSHORE REPORTING VISBYS GENERALLY < 2NM IN SEA FOG SO LOWERED COASTAL VISIBYS POST WARM FRONTAL PASSAGE. FRONT SHOULD PUSH THRU IN THE LATE AFTN & EVNG HOURS BRINGING SOME GRADUAL IMPROVEMENT IN AVIATION CONDITIONS SUNDAY NIGHT. 47 && .PREV DISCUSSION... /ISSUED 1021 PM CDT SAT APR 5 2014/ A WARM FRONTAL BOUNDARY LYING NEARLY PARALLEL TO THE COASTLINE... BOUNDARY ANALYZED JUST ONSHORE AT 02Z. A VEERING WIND WITH HEIGHT HAS BROUGHT HIGHER SOUTHWESTERN MOISTURE OVER OUR INLAND COOLER DRIER AIR MASS AND GENERATED EITHER DRIZZLE OR LIGHT PASSING SHOWERS. INCREASING RAIN CHANCES THROUGH THE OVERNIGHT SUNDAY MORNING HOURS AS WEAK VORTICITY RIDES OUT OF SOUTHWESTERN TEXAS OVER THE COMING HOURS AND PROVIDES MORE LIFT. 25HJET STREAK HEADING OUT OF THE BIG BEND AT 00Z THAT MAY ALSO CONTRIBUTE TO BETTER OVERALL RAIN PRECIPITATION COVERAGE THROUGH MID-DAY SUNDAY. SOUTHERN BRANCH OF POLAR JET POSITIONING ITSELF DEAD- CENTER OVER EASTERN TEXAS SO THESE MORE DIFFULENT UPPER LEVELS WILL ENHANCE THIS GENTLE WAA PATTERN LIFT. 7-8H WARM LAYER WILL KEEP ANY CONVECTION ELEVATED THROUGH EARLY SUNDAY AFTERNOON... PROFILES EXPECTED TO WARM ENOUGH THROUGH THE LOWER LEVELS (AS MID-LAYERS STAY WARM) TO POSSIBLY TAP INTO STEEPER MID-LEVEL LAPSE RATES DURING SUNDAY PM...INCREASING STORM THREAT/COVERAGE. OVERCAST AND PRECIPITATION WILL MAINTAIN A LOWER DIURNAL TEMPERATURE RANGE FROM SUNDAY MORNING`S MID 50S TO LOW 60S TO THE AFTERNOON`S UPPER 60S TO MID 70S. INLAND PATCHY FOG WITH LOW CEILINGS...POCKETS OF MORE DENSE SEA FOG...THROUGH AN EARLY MONDAY MORNING COLD FRONTAL PASSAGE. 31 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 56 67 52 70 48 / 50 60 20 10 10 HOUSTON (IAH) 58 74 54 72 51 / 40 70 20 10 10 GALVESTON (GLS) 62 73 58 72 56 / 40 60 20 10 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 4 AM CDT SUNDAY FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY. SMALL CRAFT ADVISORY UNTIL 4 AM CDT SUNDAY FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
553 PM CDT SUN APR 6 2014 .UPDATE... ISSUED AT 553 PM CDT SUN APR 6 2014 THE MAIN FOCUS THIS EVENING IS ON THE BAND OF CONVECTION THAT HAS DEVELOPED ALONG THE I90 CORRIDOR IN SOUTHERN MINNESOTA. 06.21Z RAP ANALYSIS SHOWS THAT THIS AREA IS IN THE BELT OF HIGHEST INSTABILITY WITH MLCAPE BETWEEN 500-1000J/KG IN THIS REGION. THIS AREA IN SOUTH CENTRAL MINNESOTA HAS A LITTLE BETTER SURFACE CONVERGENCE OF WINDS THANKS TO AN WEAK SURFACE TROUGH PASSING THROUGH. THE 06.21Z HRRR IS IN LINE WITH THIS DEVELOPMENT AND SHOWS IT MAINLY DEVELOPING EASTWARD ALONG THE CONVERGENCE IN SOUTHEAST MINNESOTA AND WEAKENING AS IT REACHES WESTERN WISCONSIN. AS THE INSTABILITY WEAKENS LATER THIS EVENING...EXPECT THAT COVERAGE OF THE SHOWERS WILL BECOME LESS AS WELL. FREEZING LEVELS ARE FAIRLY LOW AT 6-7KFT ALONG WITH DONOVAN HEIGHTS ONLY BEING AROUND 17KFT...BUT THINK THAT LACK OF LOW LEVEL SHEAR WILL KEEP ANY UPDRAFTS FROM BEING SUSTAINED. ONE COCORAHS REPORT OF PEA SIZED HAIL NEAR ELLENDALE MN ALREADY AND THAT SHOULD BE ABOUT THE EXTENT OF HOW HIGH THE HAIL GETS. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 233 PM CDT SUN APR 6 2014 FORECAST CONCERN IS RAIN CHANCES TONIGHT THROUGH MONDAY. 19Z SURFACE ANALYSIS SHOWS HIGH PRESSURE NEAR DETROIT AND LOW PRESSURE FROM MN TO NEBRASKA. SOUTHERLY FLOW BETWEEN THE TWO LEADING TO CLOUD COVER AND SOME SHOWER ACTIVITY ACROSS IA. SATELLITE IMAGERY SHOWING CUMULUS DEVELOPMENT NOW ACROSS SOUTHERN MN WHERE MOST UNSTABLE AIR SEEN JUST NORTH OF WHERE THE THICKER CLOUD SHIELD HAS BEEN ALL DAY. WATER VAPOR IMAGERY SHOWS WAVE MOVING THROUGH WESTERN ND AND WILL HELP TO DRIVE THE LOW PRESSURE AND ASSOCIATED FRONT ACROSS THE REGION BY MONDAY. MEANWHILE A LARGER SHORT WAVE TROUGH ACROSS THE SOUTHERN PLAINS IS MOVING NORTHEAST INTO THE OHIO VALLEY. MAIN CONCERN IS RAIN CHANCES WITH THESE FEATURES. LOOKING LIKE THE INITIAL CLOUD BAND AND INSTABILITY WILL LEAD TO SOME LOW CHANCES FOR RAIN OR EVEN ISOLATED THUNDERSTORMS THROUGH EVENING. RAIN CHANCES WANE FOR A TIME...BUT INCREASE AGAIN OVERNIGHT INTO MONDAY AS THE WAVE AND FRONT MOVE IN...AIDED BY DEFORMATION ON THE NORTHWEST FLANK OF THE SOUTHERN STREAM SYSTEM. RAIN AMOUNTS WILL BE LIGHT HOWEVER. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 233 PM CDT SUN APR 6 2014 LOOKING LIKE A MORE MILD OR NORMAL APRIL TEMPERATURE REGIME WILL TAKE HOLD THIS WEEK. GENERALLY ZONAL FLOW WITH WEAK RIDGING FOR A FEW DAYS AND WEAK TROUGHING FOR A FEW. SHORT WAVE TROUGH WILL MOVE ACROSS SOUTHERN CANADA TUE/WED...AND INTO ONTARIO BY THURSDAY. SOUTHERLY WINDS AND RIDGING AHEAD OF THIS FEATURE WILL LEAD TO TEMPERATURES WELL INTO THE 60S BY WEDNESDAY. COLD FRONT TRAILING THIS SYSTEM POSES PROBABLY THE BIGGEST DILEMMA OF THIS FORECAST PERIOD. PREVIOUS MODEL SOLUTIONS SUGGESTED THE FRONT WOULD HANG UP SOMEWHERE ACROSS THE LOCAL AREA...LEADING TO POTENTIAL FOR SIGNIFICANT RAINFALL. BUT LATER SOLUTIONS NOW POINTING TO SOME WEAKER SHORT WAVE ENERGY DROPPING IN BEHIND THE FIRST ONE... RESULTING IN A MORE PROGRESSIVE FRONTAL PUSH WITH A MORE TRANSIENT RAIN EVENT. GFS HAD LATCHED ONTO THIS ALREADY WITH ITS 06Z RUN...AND 12Z CONTINUED. LATEST 12Z ECMWF NOW ALSO ON BOARD WITH THIS. WITH MODELS STILL TRYING TO SETTLE ON A SOLUTION... DEFINITELY HAVE TO KEEP AN EYE ON THIS. FOR NOW WAS CONSERVATIVE WITH CHANGES FROM THE PREVIOUS FORECAST. BUT MAY BE ABLE TO LOWER THE RAIN CHANCES SATURDAY IF THIS TREND CONTINUES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1223 PM CDT SUN APR 6 2014 MAIN CONCERN THROUGH THE PERIOD WILL BE RAIN CHANCES THIS AFTERNOON INTO TONIGHT AND FOG POTENTIAL LATE TONIGHT THROUGH EARLY MONDAY MORNING. CURRENTLY WATCHING A MID-LEVEL TROUGH OF LOW PRESSURE MOVING ACROSS THE DAKOTAS INTO MN. LIFT AHEAD OF THIS TROUGH WILL PRODUCE SCATTERED SHRA ACTIVITY WITH AFTERNOON HEATING AND STEEPENING MID-LEVEL LAPSE RATES. WENT AHEAD AND ADDED VCSH AT BOTH KRST/KLSE AFTER 20-21Z. STILL ASSESSING IF THERE WILL BE ENOUGH INSTABILITY FOR A THUNDERSTORM OR TWO AS WELL...BUT CHANCES OF ONE AFFECTING EITHER AERODROME ARE PRETTY SMALL...SO OPTED NOT TO CARRY AT THIS POINT. CLOUD COVER THROUGH THE PERIOD LOOKS TO REMAIN VFR. LOOKING FOR THESE SHRA TO EVENTUALLY FIZZLE OUT AFTER MIDNIGHT. ATTENTION THEN TURNS TO FOG POTENTIAL MONDAY MORNING AND THIS WILL BE BASED ON AMOUNT OF CLOUD COVER. IF WE SCATTER...THIS WILL ALLOW FOR MORE RADIATIONAL COOLING AND MORE FOG AS A RESULT. THINKING CLOUD COVER SHOULD REMAIN BROKEN ENOUGH TO PREVENT THIS BUT DID INCLUDE 3-5SM BR...BANKING ON SOME HOLES IN THE SKY COVER. EXPECTING SOME REDEVELOPMENT IN SHRA MONDAY...BUT THIS DOESNT LOOK TO OCCUR UNTIL AROUND NOON. OTHERWISE...LOOK FOR RATHER GUSTY SOUTHWEST WINDS THIS AFTERNOON TO SUBSIDE TO LIGHT AND VARIABLE TONIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...HALBACH SHORT TERM...MW LONG TERM...MW AVIATION...DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1236 PM CDT SUN APR 6 2014 .UPDATE... ISSUED AT 950 AM CDT SUN APR 6 2014 UPDATED FORECAST FOR THIS AFTERNOON/EARLY EVENING TO INCLUDE A CHANCE OF THUNDERSTORMS. LATEST WATER VAPOR SHOWS MID-LEVEL TROUGH MOVING EAST OUT OF THE DAKOTAS WITH A WEAK SURFACE LOW AND TROUGH MOVING EAST THROUGH MN. RAP MODEL BRINGS IN A 0-3KM MUCAPE POOL OF 500-1000 J/KG BUILDING AHEAD OF THE TROUGH THIS AFTERNOON IN ASSOCIATION WITH STEEPENING MID-LEVEL LAPSE RATES. RAP DEW POINTS SEEM A BIT OVERDONE IN THE M-U40S...BUT MODIFIED CAPE WITH DEW POINTS IN THE LOWER 40S WOULD STILL YIELD 300-800J/KG. THIS IS ENOUGH TO SUPPORT A FEW STRONGER UPDRAFTS FOR A FEW THUNDERSTORMS WITH ENOUGH SURFACE HEATING. OTHERWISE...MORE SPRING-LIKE TEMPERATURES LOOK ON TRACK TODAY...TOPPING OFF IN THE MID 50S NORTH OF I-94...TO A FEW LOWER 60S SOUTH OF I-90. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 245 AM CDT SUN APR 6 2014 UPPER LEVEL TROUGH IS MOVING EASTWARD ACROSS THE NATION/S MID- SECTION...AND WILL LIFT NORTHEAST INTO THE OH RIVER VALLEY ON MONDAY. ITS ASSOCIATED SFC LOW WILL FOLLOW SUIT. THIS TRACK WOULD KEEP THE SYSTEM/S DEFORMATION REGION OF PCPN NORTH-WEST OF THE LOW SOUTH OF THE LOCAL AREA. HOWEVER...THERE REMAINS SUBTLE FEATURES THAT COULD STILL RESULT IN SOME PCPN. NAM/GFS/ECMWF ALL CONTINUE TO SHOW WEAK AREAS OF LOW LEVEL CONVERGENCE AND LOW LEVEL WARMING...WITH SOME MINOR RIPPLES MOVING DOWN THE MEAN UPPER LEVEL TROUGH. THIS MAKES TIMING/PLACEMENT OF EVEN SLIGHT CHANCES PROBLEMATIC...AND WILL LIKELY USE BROAD STROKES WITH THE CHANCES DUE TO THIS UNCERTAINTY. HOWEVER...THE MODELS DUE HINT THAT A SLIGHTLY STRONGER SHORTWAVE WILL WORK SOUTHEAST INTO THE NORTHERN PLAINS ON MONDAY...DROPPING INTO THE MID MISSISSIPPI RIVER VALLEY LATER THAT NIGHT. THIS FEATURE...COUPLED WITH THE AFOREMENTIONED WEAKER SIGNALS...COULD BRING THE BEST CHANCE FOR SOME LIGHT PCPN MONDAY/MONDAY NIGHT. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 245 AM CDT SUN APR 6 2014 UPPER LEVEL FLOW STILL SLATED TO BE MORE ZONAL TO RIDGING FOR MUCH OF THE NEW WEEK...KEEPING THE REGION UNDER A RELATIVELY MILD AIR MASS. 850 MB TEMP ANOMALIES VIA THE ECMWF STILL HOVER AROUND +1. IT WILL CERTAINLY FEEL MORE LIKE SPRING COMPARED TO PREVIOUS WEEKS. THAT SAID...ITS NOT GOING TO BE PCPN FREE. AN UPPER LEVEL SHORTWAVE TROUGH PROGGED TO MOVE ACROSS SOUTHERN CANADA MID WEEK...STAYING NORTH OF THE REGION AS IT PASSES WED NIGHT/THU. HOWEVER...ASSOCIATED SFC FRONT SLIPS ACROSS THE UPPER MISSISSIPPI RIVER WED NIGHT...AND THE GFS/EC SUGGEST THAT A PIECE OF UPPER LEVEL ENERGY COULD DRIVE ACROSS IT. SOME LOW/MID LEVEL QG CONVERGENCE WITH THE FRONT. SATURATION COULD BE AN ISSUE AS TIME/HEIGHT X-SECTIONS AND BUFKIT SOUNDINGS SHOW MOSTLY MID/UPPER LEVEL MOISTURE. BETTER PRECIPITATION CHANCES CURRENTLY TRENDING ACROSS NORTHERN PARTS OF THE REGION...WHERE SATURATION IS DEEPER. THE WEEKEND IS SHOWING THE MOST PROMISE FOR A SIGNIFICANT SYSTEM TO SLIDE OVER THE UPPER MISSISSIPPI RIVER VALLEY. TROUGH SLATED TO MOVE FROM THE NORTHERN PLAINS TO ACROSS THE GREAT LAKES WHILE A SFC LOW ASSOCIATED WITH SOME UPPER LEVEL ENERGY ACROSS THE SOUTHERN PLAINS TAKES A NORTHEAST TRACK TOWARD THE REGION. DIFFERENCES BETWEEN THE GFS AND THE PREV ECMWF RUN...WITH THE EC A BIT FASTER. HOWEVER...THE 06.00Z EC IS MORE INLINE WITH THE GFS THINKING. WITH THE GULF OPEN AND A STRONG FEED OF LOW LEVEL MOISTURE INTO AN ASSOCIATED COLD FRONT...A BROAD AREA OF PCPN LOOKS LIKELY...WITH COPIOUS AMOUNTS OF RAIN FALLING ON THE REGION. IF REALIZED...WOULD LIKELY SEE RISES ON AREA RIVERS/STREAMS. GOING TO SIDE WITH THE CONSENSUS SOLUTION FOR NOW. THIS SCENARIO IS SOMETHING TO WATCH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1223 PM CDT SUN APR 6 2014 MAIN CONCERN THROUGH THE PERIOD WILL BE RAIN CHANCES THIS AFTERNOON INTO TONIGHT AND FOG POTENTIAL LATE TONIGHT THROUGH EARLY MONDAY MORNING. CURRENTLY WATCHING A MID-LEVEL TROUGH OF LOW PRESSURE MOVING ACROSS THE DAKOTAS INTO MN. LIFT AHEAD OF THIS TROUGH WILL PRODUCE SCATTERED SHRA ACTIVITY WITH AFTERNOON HEATING AND STEEPENING MID-LEVEL LAPSE RATES. WENT AHEAD AND ADDED VCSH AT BOTH KRST/KLSE AFTER 20-21Z. STILL ASSESSING IF THERE WILL BE ENOUGH INSTABILITY FOR A THUNDERSTORM OR TWO AS WELL...BUT CHANCES OF ONE AFFECTING EITHER AERODROME ARE PRETTY SMALL...SO OPTED NOT TO CARRY AT THIS POINT. CLOUD COVER THROUGH THE PERIOD LOOKS TO REMAIN VFR. LOOKING FOR THESE SHRA TO EVENTUALLY FIZZLE OUT AFTER MIDNIGHT. ATTENTION THEN TURNS TO FOG POTENTIAL MONDAY MORNING AND THIS WILL BE BASED ON AMOUNT OF CLOUD COVER. IF WE SCATTER...THIS WILL ALLOW FOR MORE RADIATIONAL COOLING AND MORE FOG AS A RESULT. THINKING CLOUD COVER SHOULD REMAIN BROKEN ENOUGH TO PREVENT THIS BUT DID INCLUDE 3-5SM BR...BANKING ON SOME HOLES IN THE SKY COVER. EXPECTING SOME REDEVELOPMENT IN SHRA MONDAY...BUT THIS DOESNT LOOK TO OCCUR UNTIL AROUND NOON. OTHERWISE...LOOK FOR RATHER GUSTY SOUTHWEST WINDS THIS AFTERNOON TO SUBSIDE TO LIGHT AND VARIABLE TONIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...DAS SHORT TERM...RIECK LONG TERM....RIECK AVIATION...DAS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1011 AM CDT SUN APR 6 2014 .UPDATE... ISOLATED SHOWERS NORTH AND WEST OF THE CWA BUT SO FAR ONLY HITTING THE GROUND IN CENTRAL IOWA. MESO MODELS KEEP MAJORITY OF THE PRECIP TO THE NORTHWEST WITH A FEW SHOWERS CLIPPING OUR NORTHWEST COUNTIES. MAY ADD LOW POPS FOR RAIN SHOWERS THIS AFTERNOON IN THIS REGION. SOUNDINGS INDICATE THERE IS STILL A LOT OF DRY AIR AT LOWER LEVELS TO OVERCOME IF ANYTHING DEVELOPS. BETTER INSTABILITY IS NORTHWEST OF THE CWA AND THE RAP INDICATES AROUND 50 J/KG OF CAPE IN THE FAR NW CWA. && .AVIATION/18Z TAFS/... VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE DAY MONDAY. THERE COULD BE A SPRINKLE IN THE WEST...BUT OTHERWISE IT LOOKS DRY THROUGH TONIGHT. A SHORTWAVE MAY BRING SOME SHOWERS MONDAY AFTERNOON...MAINLY FOR AREAS WEST OF A LINE FROM FOND DU LAC TO JANESVILLE. A RUMBLE OR TWO OF THUNDER IS NOT OUT OF THE QUESTION BASED ON LATEST NAM SOUNDINGS. && .PREV DISCUSSION... /ISSUED 329 AM CDT SUN APR 6 2014/ TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. A LARGE MID/UPPER TROUGH ACROSS THE HIGH PLAINS THIS AFTERNOON WILL BEGIN TO LIFT NORTHEAST TOWARDS THE MISSISSIPPI VALLEY LATE TONIGHT. A RATHER STRONG 250 MB JET MAX OF 120 KNOTS MOVES ACROSS THE SOUTHERN GREAT LAKES WITH THE ENTRANCE REGION ACROSS SOUTHERN WISCONSIN TONIGHT. THIS BRINGS MODERATE UPPER DIVERGENCE TO THE ILLINOIS BORDER REGION EARLY MONDAY MORNING. SATURATION DOES OCCUR AT 700 MB...BUT 700 MB UPWARD MOTION IS RATHER WEAK AND THE LOWER LEVELS BELOW 800 MB ARE DRY. THERE IS SOME MID LEVEL INSTABILITY WITH ONLY 4 JOULES/KG. THEREFORE THERE IS SOME POTENTIAL FOR ACCAS/VIRGA MAINLY WEST OF MADISON BUT ANY MEASURABLE PRECIPITATION IS QUESTIONABLE. WARM AIR ADVECTION CONTINUES IN THE 925/850 AND 700 MB LEVELS TODAY. SURFACE RIDGE OF HIGH PRESSURE MOVES TO THE MID ATLANTIC COAST AREA WITH MAINLY LIGHT SOUTH FLOW ACROSS SOUTHERN WISCONSIN TODAY. WILL NOT BE STRONG ENOUGH TO PREVENT A LAKE BREEZE FROM PUSHING INLAND LATE MORNING AND AFTERNOON. SHORT TERM...MONDAY THROUGH TUESDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM. NAM/ECMWF KEEP SURFACE LOW PRESSURE AND 500 MB SHORTWAVE TROUGH TRACKS FAR ENOUGH TO THE SOUTHEAST MONDAY TO KEEP PRECIPITATION SHIELD SOUTHEAST OF THE AREA. THE GFS/CANADIAN MODELS TRY TO CLIP THE FAR SOUTHEAST COUNTIES WITH THE PRECIPITATION SHIELD MAINLY MONDAY AFTERNOON...AS THEY ARE A BIT SLOWER AND SLIGHTLY TO THE NORTHWEST OF THE NAM/ECMWF LOW/SHORTWAVE TROUGH TRACKS. PREFER THE MORE CONSISTENT NAM/ECMWF TRACKS WITH THIS SYSTEM. MODELS STILL TRY TO BRING LIGHT QPF INTO THE WESTERN COUNTIES MONDAY WITH WEAK TO MODEST LOW LEVEL FRONTOGENESIS RESPONSE/DEFORMATION ZONE. AREA FORECAST SOUNDINGS CONTINUE TO SHOW DECENT MOISTURE IN LOW TO MID LEVELS...WITH SOMEWHAT STEEP LOW TO MID LEVEL LAPSE RATES. VERY WEAK INSTABILITY SEEN IN FAR WESTERN AREAS. LEFT CHANCE POPS IN THE WEST GOING...WITH SLIGHT CHANCE POPS IN THE SOUTHEAST IN THE AFTERNOON. KEPT LOWER END POPS GOING FOR NOW MONDAY NIGHT INTO TUESDAY...UNTIL MAIN 500 MB SHORTWAVE TROUGH SLIDES SOUTHEAST THROUGH THE AREA. MOISTURE PROFILES ARE QUESTIONABLE...ESPECIALLY ON NAM...WITH ANY MOIST AREAS SHALLOW AND NOT VERY PERSISTENT. COULD END UP BEING SPRINKLES OR VIRGA DURING THIS PERIOD IF BETTER MOISTURE DOES NOT MATERIALIZE. QUIET WEATHER RETURNS BY TUESDAY NIGHT. NORTH TO NORTHEAST WINDS MONDAY SHOULD KEEP HIGHS IN THE 40S NEAR THE LAKE...WITH AROUND 50 WELL INLAND. HIGHS TUESDAY SHOULD RISE INTO THE LOWER 50S INLAND...WITH A LAKE BREEZE DEVELOPING IN THE AFTERNOON NEAR THE LAKE. LONG TERM...WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS MEDIUM. GFS/ECMWF AGREE ON STRONG WARM AIR ADVECTION DEVELOPING WEDNESDAY INTO EARLY THURSDAY ACROSS THE AREA. THIS SHOULD ALLOW HIGHS TO RISE INTO THE LOWER TO MID 60S WEDNESDAY AND THURSDAY...BEFORE COLD FRONT SLIDES SOUTHEAST THROUGH THE AREA. HIGHS MAY NEED TO BE WARMER NEAR THE LAKE WEDNESDAY INTO THURSDAY GIVEN PERSISTENT SOUTHWEST FLOW. COLD FRONT SLIDES SOUTHEAST ACROSS THE AREA THURSDAY...FOLLOWED BY A 500 MB VORTICITY MAXIMUM. THIS SYSTEM SHOULD BRINGING ENOUGH MOISTURE FOR AT LEAST CHANCES FOR LIGHT RAIN. NEXT ROUND OF WARM AIR ADVECTION THEN TRIES TO SET UP FOR SATURDAY...WITH MODELS SHOWING VARYING LOCATIONS OF LOW PRESSURE AND OTHER FEATURES. FOR NOW...USED CONSENSUS POPS AND TEMPERATURES IN THIS PORTION OF THE FORECAST. AVIATION/12Z TAFS/... VFR CONDITIONS THROUGH THE FORECAST. SURFACE RIDGE OF HIGH PRESSURE MOVES TO THE MID ATLANTIC COAST AREA WITH MAINLY LIGHT SOUTH FLOW ACROSS SOUTHERN WISCONSIN TODAY. WILL NOT BE STRONG ENOUGH TO PREVENT A LAKE BREEZE FROM PUSHING INLAND LATE MORNING AND AFTERNOON. MID LEVEL MOISTURE INCREASES LATER TODAY OVER SOUTH CENTRAL WISCONSIN AND ACROSS MUCH OF THE AREA TONIGHT. MARINE... LIGHT SOUTH WINDS WILL BECOME SOUTHEAST BY AFTERNOON AS HIGH PRESSURE MOVES OFF TO THE EAST. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...SM/DDV TODAY/TONIGHT AND AVIATION/MARINE...HENTZ MONDAY THROUGH SATURDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
950 AM CDT SUN APR 6 2014 .UPDATE... ISSUED AT 950 AM CDT SUN APR 6 2014 UPDATED FORECAST FOR THIS AFTERNOON/EARLY EVENING TO INCLUDE A CHANCE OF THUNDERSTORMS. LATEST WATER VAPOR SHOWS MID-LEVEL TROUGH MOVING EAST OUT OF THE DAKOTAS WITH A WEAK SURFACE LOW AND TROUGH MOVING EAST THROUGH MN. RAP MODEL BRINGS IN A 0-3KM MUCAPE POOL OF 500-1000 J/KG BUILDING AHEAD OF THE TROUGH THIS AFTERNOON IN ASSOCIATION WITH STEEPENING MID-LEVEL LAPSE RATES. RAP DEW POINTS SEEM A BIT OVERDONE IN THE M-U40S...BUT MODIFIED CAPE WITH DEW POINTS IN THE LOWER 40S WOULD STILL YIELD 300-800J/KG. THIS IS ENOUGH TO SUPPORT A FEW STRONGER UPDRAFTS FOR A FEW THUNDERSTORMS WITH ENOUGH SURFACE HEATING. OTHERWISE...MORE SPRING-LIKE TEMPERATURES LOOK ON TRACK TODAY...TOPPING OFF IN THE MID 50S NORTH OF I-94...TO A FEW LOWER 60S SOUTH OF I-90. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 245 AM CDT SUN APR 6 2014 UPPER LEVEL TROUGH IS MOVING EASTWARD ACROSS THE NATION/S MID- SECTION...AND WILL LIFT NORTHEAST INTO THE OH RIVER VALLEY ON MONDAY. ITS ASSOCIATED SFC LOW WILL FOLLOW SUIT. THIS TRACK WOULD KEEP THE SYSTEM/S DEFORMATION REGION OF PCPN NORTH-WEST OF THE LOW SOUTH OF THE LOCAL AREA. HOWEVER...THERE REMAINS SUBTLE FEATURES THAT COULD STILL RESULT IN SOME PCPN. NAM/GFS/ECMWF ALL CONTINUE TO SHOW WEAK AREAS OF LOW LEVEL CONVERGENCE AND LOW LEVEL WARMING...WITH SOME MINOR RIPPLES MOVING DOWN THE MEAN UPPER LEVEL TROUGH. THIS MAKES TIMING/PLACEMENT OF EVEN SLIGHT CHANCES PROBLEMATIC...AND WILL LIKELY USE BROAD STROKES WITH THE CHANCES DUE TO THIS UNCERTAINTY. HOWEVER...THE MODELS DUE HINT THAT A SLIGHTLY STRONGER SHORTWAVE WILL WORK SOUTHEAST INTO THE NORTHERN PLAINS ON MONDAY...DROPPING INTO THE MID MISSISSIPPI RIVER VALLEY LATER THAT NIGHT. THIS FEATURE...COUPLED WITH THE AFOREMENTIONED WEAKER SIGNALS...COULD BRING THE BEST CHANCE FOR SOME LIGHT PCPN MONDAY/MONDAY NIGHT. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 245 AM CDT SUN APR 6 2014 UPPER LEVEL FLOW STILL SLATED TO BE MORE ZONAL TO RIDGING FOR MUCH OF THE NEW WEEK...KEEPING THE REGION UNDER A RELATIVELY MILD AIR MASS. 850 MB TEMP ANOMALIES VIA THE ECMWF STILL HOVER AROUND +1. IT WILL CERTAINLY FEEL MORE LIKE SPRING COMPARED TO PREVIOUS WEEKS. THAT SAID...ITS NOT GOING TO BE PCPN FREE. AN UPPER LEVEL SHORTWAVE TROUGH PROGGED TO MOVE ACROSS SOUTHERN CANADA MID WEEK...STAYING NORTH OF THE REGION AS IT PASSES WED NIGHT/THU. HOWEVER...ASSOCIATED SFC FRONT SLIPS ACROSS THE UPPER MISSISSIPPI RIVER WED NIGHT...AND THE GFS/EC SUGGEST THAT A PIECE OF UPPER LEVEL ENERGY COULD DRIVE ACROSS IT. SOME LOW/MID LEVEL QG CONVERGENCE WITH THE FRONT. SATURATION COULD BE AN ISSUE AS TIME/HEIGHT X-SECTIONS AND BUFKIT SOUNDINGS SHOW MOSTLY MID/UPPER LEVEL MOISTURE. BETTER PRECIPITATION CHANCES CURRENTLY TRENDING ACROSS NORTHERN PARTS OF THE REGION...WHERE SATURATION IS DEEPER. THE WEEKEND IS SHOWING THE MOST PROMISE FOR A SIGNIFICANT SYSTEM TO SLIDE OVER THE UPPER MISSISSIPPI RIVER VALLEY. TROUGH SLATED TO MOVE FROM THE NORTHERN PLAINS TO ACROSS THE GREAT LAKES WHILE A SFC LOW ASSOCIATED WITH SOME UPPER LEVEL ENERGY ACROSS THE SOUTHERN PLAINS TAKES A NORTHEAST TRACK TOWARD THE REGION. DIFFERENCES BETWEEN THE GFS AND THE PREV ECMWF RUN...WITH THE EC A BIT FASTER. HOWEVER...THE 06.00Z EC IS MORE INLINE WITH THE GFS THINKING. WITH THE GULF OPEN AND A STRONG FEED OF LOW LEVEL MOISTURE INTO AN ASSOCIATED COLD FRONT...A BROAD AREA OF PCPN LOOKS LIKELY...WITH COPIOUS AMOUNTS OF RAIN FALLING ON THE REGION. IF REALIZED...WOULD LIKELY SEE RISES ON AREA RIVERS/STREAMS. GOING TO SIDE WITH THE CONSENSUS SOLUTION FOR NOW. THIS SCENARIO IS SOMETHING TO WATCH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 640 AM CDT SUN APR 6 2014 SOUTHWEST WINDS AHEAD OF AN APPROACHING SHORT WAVE TROUGH WILL CONTINUE TO BRING A BROKEN DECK OF CLOUDS AT OR ABOVE 8K FEET THROUGH 07.08Z...AND THEN CEILINGS WILL LOWER TO 5K FEET. THERE WILL BE A SLIGHT CHANCE OF SHOWERS FROM 06.22Z THROUGH 07.12Z. THE LAMP DATA SUGGESTS THAT FG WILL DEVELOP AT KRST AFTER 07.08Z. HOWEVER WITH CLOUDS IN PLACE AND WINDS REMAINING ABOVE 5 KNOTS...JUST DO NOT SEE THIS OCCURRING...SO DID NOT INCLUDE IT INT THE TAF. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...DAS SHORT TERM...RIECK LONG TERM....RIECK AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
356 AM EDT TUE APR 8 2014 .SYNOPSIS... A COLD FRONT CROSSING THE MIDLANDS EARLY THIS MORNING WILL MOVE OFF THE COAST SHORTLY AFTER SUNRISE. A TROUGH OF LOW PRESSURE WILL SWING THROUGH THE AREA TONIGHT. HIGH PRESSURE WILL TAKE CONTROL FOR THE LATTER HALF OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... THE LAST OF THE SHOWERS WILL CROSS THE MIDLANDS THIS MORNING AS A COLD FRONT CROSSING THE MIDLANDS AND CSRA MAKES ITS WAY TO THE COAST. SHOWERS CROSSING THE AREA EARLY THIS MORNING ARE EXPECTED TO MOVE EAST OF THE MIDLANDS FROM AROUND MID-MORNING AS COLD AIR ADVECTION SPREADS EAST AND DEEP MOISTURE MOVES OUT OF THE AREA. TEMPERATURES IN THE UPPER 50S WEST TO UPPER 60S EAST SHOULD FALL A FEW DEGREES AFTER THE COLD FRONT MOVES EAST. A DEEP UPPER-LEVEL TROUGH OVER THE CENTRAL STATES WILL CROSS OUR AREA TONIGHT AND WEDNESDAY. THE COLD AIR ALOFT ASSOCIATED WITH THE TROUGH AND ITS WEAK SURFACE REFLECTION WILL BRING SCATTERED SHOWERS TONIGHT INTO WEDNESDAY. AN AVERAGE OF THE GFS AND NAM MOS SUPPORT POPS AROUND 20 PERCENT. WE ARE EXPECTING HIGH TEMPERATURES IN THE UPPER 60S AND LOWER 70S TODAY. KEPT LOWS IN THE MID TO UPPER 40S TONIGHT. SEASONABLE READING IN THE UPPER 60S TO MID 70S ARE FORECAST IN SPITE OF SCATTERED SHOWERS ON WEDNESDAY. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... THE UPPER TROUGH WILL MOVE OFF THE COAST WEDNESDAY NIGHT WITH A NEARLY ZONAL FLOW DEVELOPING ACROSS THE EASTERN STATES. AT THE SURFACE ...HIGH PRESSURE WILL BUILD ACROSS THE REGION WEDNESDAY NIGHT AND THURSDAY...BUT CONTINUE TO RIDGE INTO THE AREA THROUGH FRIDAY NIGHT. A WARMING TREND IS ON TAP AS WINDS BECOME SOUTHERLY. HIGH TEMPERATURES WILL BE IN THE 70S. LOWS IN THE LOW/MID 40S WEDNESDAY NIGHT WILL MODERATE TO THE LOWER 50S BY FRIDAY NIGHT. && .LONG TERM /SATURDAY THROUGH MONDAY/... THE GFS AND ECMWF INDICATE A DRY PATTERN WITH HIGH PRESSURE DOMINATING THROUGH THE WEEKEND. THE MODELS SHOW ANOTHER COLD FRONT AND ASSOCIATED MOISTURE AFFECTING THE AREA MONDAY. THE GFS AND ECMWF MOS SUPPORT ABOVE NORMAL READINGS SATURDAY AND SUNDAY. THE GFS AND ECMWF MOS SUPPORT POPS OF 30 TO 40 PERCENT MONDAY. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... BULK OF SHOWERS ARE SLOWLY MOVING EAST AND EXITING THE FORECAST AREA TONIGHT. A FEW SHOWER MOVING NORTHEAST AHEAD OF A NARROW LINE OF SHOWERS ASSOCIATED WITH THE COLD FRONT. THIS LINE IS PUSHING FROM THE PIEDMONT REGION INTO THE MIDLANDS AND WILL CROSS THE AREA BY MORNING. CONDITIONS ARE IFR AT ALL TAF SITES AND SHOULD REMAIN SO THROUGH THE EARLY MORNING HOURS. LAMP GUIDANCE AND HRRR LEANING TOWARDS IFR/POSSIBLE LIFR CIGS THROUGH THE OVERNIGHT. HAVE LEANED TOWARDS IFR CIGS THROUGH 12Z TUESDAY AT ALL TAF SITES. FRONTAL BOUNDARY EXPECTED TO MOVE THROUGH AROUND 09Z TO 12Z. RADAR TRENDS INDICATING A FEW SHOWERS AHEAD OF THE COLD FRONT. WILL HANDLE WITH A MENTION OF -SHRA IN MAIN GROUP OR TEMPO FOR THE NEXT FEW HOURS. EXPECT LITTLE IMPROVEMENT BUT WITH A WIND SHIFT TO THE WEST TOWARDS DAYBREAK. THEN A GRADUAL IMPROVEMENT FROM IFR TO MVFR AND EVENTUALLY VFR BY LATER THIS MORNING. CIGS SHOULD BECOME VFR AT ALL TAF SITES BY TUESDAY AFTERNOON. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
150 AM EDT TUE APR 8 2014 .SYNOPSIS... A COLD FRONT APPROACHING FROM THE WEST WILL MOVE THROUGH THE FORECAST AREA LATE TONIGHT. A LINGERING TROUGH IN THE FORECAST AREA WILL MOVE OUT OF THE AREA WEDNESDAY WITH HIGH PRESSURE DOMINATING DURING THE REST OF THE WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... SCATTERED SHOWERS CONTINUE TO DEVELOP IN THE REGION BETWEEN THE DEPARTING STRONG CONVECTION OFF THE COAST AND THE COLD FRONT TO THE WEST. SLIGHTLY DIFFLUENT FLOW AT 500MB AND MODERATE SOUTHWESTERLY LOW LEVEL FLOW CONTINUE TO PROVIDE LIFT AND MOISTURE FOR ADDITIONAL SHOWERS. THE COLD FRONT WILL PUSH THROUGH THE FORECAST AREA DURING THE 09Z-12Z TIME FRAME AND PRECIPITATION WILL END FROM WEST TO EAST AS THE FRONT PASSES. TEMPERATURES CONTINUE TO WARM AHEAD OF THE FRONT AS THE WEDGE ERODES AND SOUTHERLY FLOW PERSISTS. OVERNIGHT LOWS WILL BE HIGHLY DEPENDENT ON HOW FAR EAST THE FRONT GETS BY 12Z AND HAVE LOWS RANGING FROM THE LOWER 50S WEST TO AROUND 60 EAST. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... THE COLD FRONT WILL BE EAST OF THE FORECAST AREA BY SUNRISE TUESDAY. HOWEVER...THE DEEP UPPER-LEVEL TROUGH IS NOT FORECAST TO SWING THROUGH THE AREA UNTIL TUESDAY NIGHT AND WEDNESDAY. THE COLD AIR ALOFT ASSOCIATED WITH THE TROUGH AND ITS WEAK SURFACE REFLECTION MAY HELP CAUSE SCATTERED SHOWERS TUESDAY INTO WEDNESDAY. AN AVERAGE OF THE GFS AND NAM MOS SUPPORT POPS AROUND 20 PERCENT. WE USED THE COOLER HIGH TEMPERATURE GUIDANCE BECAUSE OF THE SHARP UPPER-LEVEL TROUGH TUESDAY. STRONG NET RADIATIONAL COOLING SUPPORTED THE COLDER TEMPERATURE GUIDANCE WEDNESDAY NIGHT. && .LONG TERM /THURSDAY THROUGH MONDAY/... THE GFS AND ECMWF INDICATE A DRY PATTERN WITH HIGH PRESSURE DOMINATING THROUGH THE WEEKEND. THE MODELS SHOW ANOTHER COLD FRONT AND ASSOCIATED MOISTURE AFFECTING THE AREA MONDAY. THE GFS AND ECMWF MOS SUPPORT NEAR- NORMAL TEMPERATURES THURSDAY AND FRIDAY...WITH ABOVE NORMAL READINGS SATURDAY AND SUNDAY. THE GFS AND ECMWF MOS SUPPORT POPS OF 30 TO 40 PERCENT MONDAY. && .AVIATION /06Z TUESDAY THROUGH SUNDAY/... BULK OF SHOWERS ARE SLOWLY MOVING EAST AND EXITING THE FORECAST AREA TONIGHT. A FEW SHOWER MOVING NORTHEAST AHEAD OF A NARROW LINE OF SHOWERS ASSOCIATED WITH THE COLD FRONT. THIS LINE IS PUSHING FROM THE PIEDMONT REGION INTO THE MIDLANDS AND WILL CROSS THE AREA BY MORNING. CONDITIONS ARE IFR AT ALL TAF SITES AND SHOULD REMAIN SO THROUGH THE EARLY MORNING HOURS. LAMP GUIDANCE AND HRRR LEANING TOWARDS IFR/POSSIBLE LIFR CIGS THROUGH THE OVERNIGHT. HAVE LEANED TOWARDS IFR CIGS THROUGH 12Z TUESDAY AT ALL TAF SITES. FRONTAL BOUNDARY EXPECTED TO MOVE THROUGH AROUND 09Z TO 12Z. RADAR TRENDS INDICATING A FEW SHOWERS AHEAD OF THE COLD FRONT. WILL HANDLE WITH A MENTION OF -SHRA IN MAIN GROUP OR TEMPO FOR THE NEXT FEW HOURS. EXPECT LITTLE IMPROVEMENT BUT WITH A WIND SHIFT TO THE WEST TOWARDS DAYBREAK. THEN A GRADUAL IMPROVEMENT FROM IFR TO MVFR AND EVENTUALLY VFR BY LATER THIS MORNING. CIGS SHOULD BECOME VFR AT ALL TAF SITES BY TUESDAY AFTERNOON. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1225 AM EDT TUE APR 8 2014 .SYNOPSIS... ISSUED AT 735 PM EDT MON APR 7 2014 A STRONG AREA OF LOW PRESSURE WILL MOVE THROUGH OHIO TONIGHT AND INTO UPSTATE NEW YORK ON TUESDAY. RAIN WILL BE OVER MUCH OF THE AREA THIS EVENING BUT WILL GRADUALLY DIMINISH FROM WEST TO EAST OVERNIGHT AS THE LOW MOVES AWAY. THERE IS A SMALL CHANCE FOR SHOWERS ON TUESDAY AS A WEAK DISTURBANCE MOVES THROUGH. LOW TEMPERATURES TONIGHT WILL FALL INTO THE MIDDLE AND UPPER 30S. HIGHS ON TUESDAY WILL GENERALLY CLIMB BACK INTO THE LOWER AND MID 50S...EXCEPT IMMEDIATELY DOWNWIND OF THE GREAT LAKES WHERE READINGS WILL STAY IN THE 40S. && .UPDATE... ISSUED AT 1215 AM EDT TUE APR 8 2014 ZONES/GRIDS UPDATED TO SLOW DEPARTURE OF RAIN SHIELD IN EASTERN AREAS. WHILE OVERALL INTENSITIES HAVE DECREASED OVER THE LAST COUPLE OF HOURS...RAIN HAS BEEN SLOW TO SHIFT EAST WITH SEVERAL RUNS OF HRRR PICKING UP ON THIS. FOLLOWING HRRR GIVES A DEPARTURE TIME IN FAR EASTERN AREAS AROUND OR AFTER 8Z...WITH GRIDS NOW POINTED IN THIS DIRECTION. WILL BE MONITORING A BROKEN AREA OF LIGHT SHOWERS EXTENDING FROM SOUTHERN WISCONSIN TO CENTRAL ILLINOIS ON THE BACK EDGE OF THE CLOUD SHIELD. HRRR HANDLED THESE FAIRLY WELL WITH A WEAKENING TREND AS THEY TRY TO MOVE EAST. WILL MAINTAIN 14 POPS WEST OF THE MAIN AREA OF RAIN THR REMAINDER OF THE NIGHT. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 332 PM EDT MON APR 7 2014 WIDESPREAD LIGHT TO MODERATE RAIN IN BURGEONING MID LEVEL DEFORMATION/FGEN REGION OF A MATURING EXTRATROPICAL CYCLONE WILL CONTINUE TO LIFT NORTH INTO THE LOCAL AREA THIS AFTERNOON/EARLY EVENING BEFORE EXITING FROM WEST TO EAST OVERNIGHT. PRIMARY CHANGE TO THE FCST WAS TO SLOW THE ARRIVAL OF RAIN INTO FAR NORTHERN ZONES THIS AFTERNOON GIVEN EXTREMELY DRY AIR BELOW 10 KFT...WITH OUR EXTREME NORTHWEST (BENTON HARBOR/MICHIGAN CITY) POTENTIALLY REMAINING DRY OR ONLY RECEIVING A COUPLE HUNDREDTHS OF RAIN GIVEN THIS DRY AIR AND MORE EASTERLY TRACK OF THE DEEPENING SFC REFLECTION NORTHEAST THROUGH OHIO/LAKE ERIE TONIGHT. RAINFALL TOTALS ACROSS SOUTHERN-EASTERN ZONES WILL GENERALLY RANGE BETWEEN 0.40" AND 0.80"...WITH A NARROW BAND UP TO AN INCH POSSIBLE NEAR PIVOT POINT (MOST LIKELY THE I-69 CORRIDOR). THIS RAINFALL MAY RESULT IN RENEWED RISES ON AREA RIVERS/STREAMS AND WILL HELP PROLONG MINOR FLOODING ON AREA RIVERS. MAINLY DRY AND COOL TOMORROW IN WAKE OF SYSTEM...ALTHOUGH THERE MAY BE JUST ENOUGH RESIDUAL LOW LEVEL MOISTURE FOR A FEW DIURNALLY DRIVEN SHOWERS AS LAPSE RATES STEEPEN UNDER THERMAL TROUGH. && .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 332 PM EDT MON APR 7 2014 TROUGH AXIS ACROSS THE AREA ON TUESDAY NIGHT WILL BRING ANOTHER NIGHT OF LOW TEMPERATURES NEAR FREEZING BEFORE WARM AIR ADVECTION KICKS IN ON WEDNESDAY AHEAD OF A STRONG LOW PRESSURE SYSTEM MOVING THROUGH SOUTHERN CANADA. WINDS WILL PICK UP THROUGH THE DAY ON WEDNESDAY REACHING 20 TO 25 MPH ON WEDNESDAY NIGHT. AT LEAST PARTLY SUNNY SKIES DURING THE FIRST PART OF THURSDAY WILL BE SUFFICIENT FOR DEEP MIXING TO NEAR 850 MB ACCORDING TO BOTH NAM AND GFS BUFKIT SOUNDINGS. THIS WILL MIX DOWN GUSTS BETWEEN 35 AND 40 MPH. BY LATER IN THE DAY...WINDS WILL WANE AS THE FRONT WASHES OUT OVER THE AREA AND THE PRESSURE GRADIENT RELAXES. MUCH OF THE FORCING ASSOCIATED WITH THE FRONT WILL BE LOST BY THE TIME IT GETS INTO OUR FORECAST AREA AND WITH THE LACK OF MOISTURE...HAVE NO PLANNED CHANGES TO CURRENT CHANCE POPS. HAVE LEFT OUT ANY MENTION OF THUNDER WITH THIS PACKAGE DUE TO AFOREMENTIONED WEAKENING FORCING AND LACK OF BETTER LOW LEVEL MOISTURE/INSTABILITY DESPITE MID LEVEL LAPSE RATES IN THE 7 TO 7.5 RANGE. DRY CONDITIONS WITH TEMPERATURES SLIGHTLY ABOVE NORMAL EXPECTED FRIDAY THROUGH SATURDAY. THE NEXT CHANCE FOR PRECIPITATION ARRIVES BY THE END OF THE WEEKEND AS A MUCH STRONGER COLD FRONT SLOWLY MOVES THROUGH THE MIDWEST. WE WILL HAVE TO MONITOR THIS SYSTEM FOR ITS HEAVY RAINFALL POTENTIAL. SEVERAL DAYS OF RETURN FLOW OFF THE GULF... A STRONGLY FORCED FRONTAL SYSTEM...AND SLOW PROGRESSION WILL SET THE STAGE FOR ANOTHER 1"+ RAINFALL EVENT. PREFER THE ECMWF DEEPER...SLOWER...MODEL SOLUTION WHICH BRINGS THE POSSIBILITY OF 70 DEGREE TEMPERATURES ON SUNDAY FOR MOST OF THE FORECAST AREA. WHILE NOT JUMPING TOTALLY ON BOARD WITH THIS SOLUTION...DID NUDGE HIGHS ON SUNDAY TOWARDS ECMWF WITH UPPER 60S ACROSS THE SE HALF OF THE FORECAST AREA. MODELS ARE ALL IN DECENT AGREEMENT REGARDING WELL BELOW NORMAL TEMPERATURES FOR THE FIRST HALF OF NEXT WEEK AFTER THIS COLD FRONT DEPARTS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1215 AM EDT TUE APR 8 2014 LOW CLOUDS HAVE REMAINED GENERALLY EAST OF KFWA MOST OF THE EVENING BUT HAVE FINALLY EDGED IN FOR WHAT SHOULD BE A SHORT VISIT AS LOW SLOWLY MOVES EAST AND DEEPER MSTR GOES WITH IT. VFR CONDITIONS EXPECTED AT KSBN THROUGH THE PERIOD WITH KFWA EVENTAULLY FOLLOWING SUIT LATER TONIGHT. NO SIG WEATHER TO WORRY ABOUT AFTER 12Z TUES AS RIDGE SLOWLY MOVES IN FROM THE WEST TO BRING DRIER WEATHER. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER SYNOPSIS...LASHLEY SHORT TERM...STEINWEDEL LONG TERM...BENTLEY AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.NORTHERNIN.GOV WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
505 AM EDT TUE APR 8 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 505 AM EDT TUE APR 8 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA AND A TROF EXTENDING FROM HUDSON BAY TO THE WRN GULF OF MEXICO. STRONG SHORTWAVE THAT WAS OVER THE SRN PLAINS 24HRS AGO IS NOW MOVING THRU THE LOWER GREAT LAKES. CLOSER TO HOME...SHORTWAVE OVER WRN UPPER MI HAS BEEN GENERATING PESKY -SHRA FROM ISLE ROYALE ACROSS THE KEWEENAW PENINSULA DURING THE NIGHT. THE -SHRA ARE DRIFTING SSE INTO PORTIONS OF CNTRL UPPER MI ATTM. MID CLOUDS ASSOCIATED WITH SHORTWAVE HAVE WORKED TO LIMIT FOG. OVER THE NEXT SEVERAL HRS...UTILIZED MOSTLY EXTRAPOLATION/TRENDS TO SHIFT AN AREA OF ISOLD/SCT -SHRA SSE FROM THE KEWEENAW TOWARD SCNTRL UPPER MI BEFORE THE -SHRA DISSIPATE. WHERE THE -SHRA ARE OCCURRING...TEMPS WILL STAY ABOVE FREEZING. IN THE WAKE OF THE -SHRA...THERE IS STILL AN OPPORTUNITY FOR -DZ/-FZDZ TO DEVELOP THIS MORNING. BEST CHC SHOULD BE OVER WRN UPPER MI. DWPT AT DISW4 IS STILL AROUND 35F. AS THIS HIGHER DWPT AIR OVER THE LAKE ADVECTS SSE INTO WRN UPPER MI WHERE SFC TEMPS ARE AT OR BLO FREEZING...STRATUS/FOG AND POTENTIALLY -FZDZ SHOULD DEVELOP. THEREAFTER...EXPECT INCREASING SUNSHINE DURING THE AFTN AS DRIER AIR ARRIVES...BREAKING UP CLOUD COVER. IT WILL BE A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR. OVER THE E WHERE THERE WILL BE A BRISK WIND ACROSS THE LAKE...TEMPS SHOULD HOLD MOSTLY IN THE LWR 30S TODAY. OTHERWISE...EXPECT GENERALLY 30S AND LWR 40S N TO AROUND 50 FAR SCNTRL FROM KIMT TO NEAR KMNM. SFC HIGH PRES RIDGE SHIFTS ACROSS THE UPPER LAKES TONIGHT... PROVIDING LIGHT/CALM WINDS FOR A GOOD PORTION OF THE NIGHT IN MOST AREAS. ON THE BACKSIDE OF THE RIDGE AND IN ADVANCE OF SHORTWAVE MOVING ACROSS THE SRN CANADIAN ROCKIES...STRENGTHENING WAA/ISENTROPIC ASCENT PATTERN TO THE NW WILL GENERATE SOME PCPN ACROSS MANITOBA INTO NRN ONTARIO TONIGHT. ALTHOUGH HIGH/MID CLOUDS WILL SPREAD SE INTO THE AREA OVERNIGHT...THERE SHOULD BE A LONG ENOUGH PERIOD OF MOSTLY CLEAR SKIES TO ALLOW A DECENT TEMP FALL. LOWERED MINS TOWARD THE LOW END OF AVBL GUIDANCE...REPRESENTED BY THE BIAS CORRECTED REGIONAL AND GLOBAL GEM. TRADITIONAL INTERIOR COLD SPOTS SHOULD FALL TO THE MID TEENS AND PERHAPS EVEN TO THE LOW TEENS OVER THE E. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 416 AM EDT TUE APR 8 2014 AFTER A COOLER DAY TODAY...WEDNESDAY WILL TRANSITION BACK TO THE ABOVE NORMAL TEMPERATURES SEEN OVER THE LAST COUPLE OF DAYS. THIS IS DUE TO AN UPPER RIDGE CURRENTLY OVER THE WESTERN CONUS SHIFTING EAST INTO THE GREAT LAKES REGION FOR WEDNESDAY AND WEDNESDAY NIGHT. AS THIS RIDGE MOVES IN...EXPECT A STRONG AREA OF WARM AIR ADVECTION AND Q-VECTOR CONVERGENCE SHIFTING EAST-SOUTHEAST ALONG THE US/CANADIAN BORDER (AND ACROSS THE NORTHERN HALF OF THE CWA) LATE TONIGHT THROUGH EARLY WEDNESDAY AFTERNOON. FOR MUCH OF THE LAND CWA...WOULD EXPECT THERE TO JUST BE SOME PASSING MID CLOUDS. BUT THERE MAY BE ENOUGH MOISTENING IN THE LOWER LEVELS TO ALLOW SOME LIGHT SPRINKLES TO AFFECT THE KEWEENAW PENINSULA. OTHERWISE...THIS AREA OF FORCING WILL QUICKLY SHIFT THROUGH AND SHOULD LEAD TO A FILTERED SUNSHINE OVER THE AREA DUE TO HIGH CLOUDS AHEAD OF THE NEXT SYSTEM. STRONG WARMING IN THE LOWER LEVELS THROUGH THE DAY ON WEDNESDAY (850MB TEMPS RISING FROM -4C AT 06Z TO AT LEAST 6C AT 00Z THURSDAY) SHOULD LEAD TO ANOTHER WARM DAY ACROSS THE CWA. WILL CONTINUE TO SHOW HIGHS IN THE UPPER 50S AND LOWER 60S OVER THE WESTERN HALF OF THE CWA AND LOWER VALUES (40S) OVER THE EAST WITH THE SOUTHWEST WINDS OFF LAKE MICHIGAN. SPEAKING OF THOSE WINDS...THEY LOOK TO BE A LITTLE GUSTY IN THE AFTERNOON (15-25KTS) AND THAT WILL ALLOW THE DOWNSLOPE AREAS TO WARM AND LIMIT LAKE BREEZE COOLING. WHILE THE WARMING IS OCCURRING ON WEDNESDAY...A SURFACE LOW WILL BE SHIFTING EAST THROUGH FAR NORTHERN ONTARIO AND A COLD FRONT WILL STRETCH SOUTHWEST INTO THE UPPER MISSISSIPPI VALLEY. MODELS REMAIN CONSISTENT ON THE TIMING OF THIS COLD FRONT MOVING THROUGH THE CWA DURING THE OVERNIGHT HOURS WEDNESDAY NIGHT AND FOR THE FIRST PART OF THURSDAY MORNING. MODELS ARE INDICATING THE BEST FORCING ALONG THE FRONT TO DIVE TO THE SOUTHEAST THROUGH WISCONSIN...BUT WILL HOLD ONTO CHANCE POPS DUE TO THE EXPECTED EASTWARD MOVEMENT OF THE UPSTREAM SHOWERS. STEEP MID LEVEL LAPSE RATES AND SHOWALTER VALUES AROUND 0 COULD PRODUCE A RUMBLE OF THUNDER OVER WESTERN LAKE SUPERIOR AND HAVE ADDED A SLIGHT CHANCE TO THE FAR WEST. WITH THE SHORTWAVE WELL BEHIND THE FRONT AND ONLY A VERY THIN LINE OF MOISTURE...EXPECT QPF AMOUNTS TO STAY BELOW 0.15IN IN MOST LOCATIONS. MOST OF THESE SHOWERS SHOULD SHIFT OUT OF THE CWA BY THE AFTERNOON. TEMPERATURES ALOFT COOL SOME BEHIND THE FRONT...BUT STILL LOOK TO BE AROUND 0C TO -2C AT 850MB. THOSE TEMPS COMBINED WITH SUNSHINE BEHIND THE FRONT WILL YIELD HIGHS IN THE UPPER 40S TO MID 50S. WITH A HIGH PRESSURE RIDGE SLIDING THROUGH THE AREA ON THURSDAY NIGHT...DRY CONDITIONS ARE EXPECTED AND TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S. FRIDAY LOOKS TO BE DRY OVER MUCH OF THE CWA...BUT THERE ARE A COUPLE SUBTLE FEATURES TO NOTE. FIRST...A SECONDARY SURFACE TROUGH TRIES TO BRUSH THE NORTHEAST THIRD OF THE CWA FRIDAY MORNING...BUT IT DOESN/T LOOK LIKE IT WILL MAKE IT THAT FAR INTO LAKE SUPERIOR. SECOND...A WEAK SHORTWAVE AND ASSOCIATED SURFACE TROUGH LOOKS TO SHIFT EAST THROUGH UPPER MICHIGAN AND WISCONSIN FRIDAY AFTERNOON/ EVENING AND COULD KICK OFF A SHOWER OR TWO. GFS IS BY FAR THE STRONGEST WITH THE WAVE BUT MOISTURE SEEMS TO BE VERY LIMITED. WILL TREND POPS UP TO LOW END SLIGHT CHANCES FOR THE AFTERNOON/EVENING...BUT CONFIDENCE IS LOW. FOR THE WEEKEND...FOCUS IS ON TWO UPPER LEVEL FEATURES THAT WILL BE OVER THE WESTERN CONUS ON FRIDAY NIGHT...ONE NEAR SOUTHERN CALIFORNIA AND THE OTHER IN THE PACIFIC NORTHWEST. THE LEADING PIECES OF ENERGY ASSOCIATED WITH THESE WAVES WILL PUSH THE FIRST WAVE OF PRECIP ACROSS THE AREA ON SATURDAY. THIS PRECIP WILL BE ASSOCIATED WITH AN ELONGATED TROUGH STRETCHING NORTHEAST FROM THE CENTRAL/SOUTHERN ROCKIES. MODELS STILL SHOWING A WIDE VARIETY OF SOLUTIONS FOR THE LOCATION OF THE TROUGH WITH THE GFS/GEM FAST/SE ECMWF FARTHEST NORTHWEST. A GENERAL BLEND WILL WORK WELL AT THIS POINT FOR POPS (CHANCES)...MOVING INTO THE WESTERN CWA SATURDAY MORNING AND SHIFTING EAST OVER THE REST OF THE AREA IN THE AFTERNOON. THE LOCATION OF THE ELONGATED TROUGH HAS A INFLUENCE ON THE WEATHER FOR THE REGION FOR THE SECOND HALF OF THE WEEKEND AND INTO MONDAY. BY THAT POINT...THE TWO WAVES THAT ARE ALONG THE WEST COAST WILL HAVE MERGED OVER THE CENTRAL CONUS AND WILL BE SHIFTING EAST. THESE FEATURES WILL BE HELPED BY A THIRD DISTURBANCE THAT WILL DROP SOUTHEAST FROM CANADA. THE TIMING OF THESE THREE FEATURES AND HOW FAR EAST THEY END UP WILL DETERMINE PRECIP CHANCES (AND MEASURABLE SNOW POSSIBILITY) FOR PARTS OF THE CWA. AS HAS BEEN THE CASE FOR THE LAST COUPLE DAYS...THE GFS IS THE FARTHEST EAST AND THE ECMWF IS THE FARTHEST WEST WHILE THE 00Z GEM IS NOW SIMILAR TO . THE GFS. WITH THE PHASING OF SEVERAL SHORTWAVES...CONFIDENCE IN ANY ONE SOLUTION IS VERY LOW AND MODELS WILL BE HIGHLY VARIABLE OVER THE NEXT COUPLE DAYS. AT THIS POINT...WILL HAVE THE HIGHER CHANCE POPS OVER THE SOUTHEAST HALF OF THE CWA...WHERE A GENERAL CONSENSUS WOULD INDICATE PRECIP. WITH THE EXPECTED COLD AIR THAT WILL SPILL IN BEHIND THE TROUGH ON SUNDAY...WOULD EXPECT THE PRECIP TO TRANSITION TO SNOW AND THERE COULD BE SOME ACCUMULATION IF THE 12Z ECMWF IS CORRECT. IN ADDITION...THE LOW LEVEL COLD AIR SURGING IN AT THE SURFACE WITH THE NORTHERLY WINDS COULD PRODUCE A 6HR PERIOD OF FREEZING RAIN. WAY TO FAR OUT TO GET TOO EXCITED AT THAT POTENTIAL AT THIS POINT...BUT IT IS SOMETHING TO WATCH. THE FIRST HALF OF NEXT WEEK LOOKS TO BE BELOW NORMAL TEMPERATURE WISE ACROSS THE GREAT LAKES REGION...AS THE UPPER LEVEL PATTERN RESEMBLES THE ONE FROM MUCH OF THIS PAST WINTER. 850MB TEMPS DO LOOK TO FALL TOWARD -12C TO -17C FOR A SHORT PERIOD DURING THE FIRST HALF OF THE WORK WEEK AND THAT COULD LEAD TO HIGHS AROUND FEEZING ON TUESDAY. FOR THOSE THAT HAVE BEEN ENJOYING THE SPRING LIKE TEMPERATURES OVER THE LAST COUPLE OF DAYS...IT APPEARS THIS TROUGH WILL LIFT OUT OF THE AREA ON WEDNESDAY AND RETURN THE AREA BACK TO NORMAL TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 132 AM EDT TUE APR 8 2014 LOW LEVEL MOISTURE AND FOG CURRENTLY OVER WRN LAKE SUPERIOR AND WRN UPPER MI WILL SHIFT SE ACROSS MUCH OF THE AREA OVERNIGHT...LEADING TO UPSLOPE LOW CLOUDS...FOG AND -DZ/-FZDZ AT ALL SITES. THERE IS UNCERTAINTY REGARDING THE EXTENT OF LOW CIGS AND VIS...BUT GIVEN THE TRENDS IN RECENT HRS OVER THE WEST...EXPECT THAT LIFR AND VLIFR CONDITIONS WILL LINGER AT CMX/IWD WHILE MAINLY MVFR DROPPING TO IFR CONDITIONS WILL PREVAIL AT SAW. THE LOW CIGS AND MVFR VSBY WILL IMPROVE DURING THE MORNING WITH VFR CONDITIONS EXPECTED BY EARLY AFTERNOON AS DRIER AIR MOVES INTO THE REGION. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 505 AM EDT TUE APR 8 2014 AS PRES GRADIENT TIGHTENS BTWN APPROACHING HIGH PRES RIDGE AND DEEPENING LOW PRES MOVING FROM THE LWR LAKES TO NEW ENGLAND...WINDS WILL PICK UP ACROSS LAKE SUPERIOR THIS MORNING...BUT MAINLY OVER THE ERN PORTION OF THE LAKE WHERE WINDS SHOULD INCREASE TO 15-25KT. WINDS WILL DIMINISH TONIGHT AS THE HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEP LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. WINDS WILL REACH THE 20-30KT RANGE...AND NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS WILL REACH GALE FORCE AT SOME POINT WED/THU. STABLE LOW-LEVEL TEMP PROFILE WILL WORK AGAINST STRONGER WINDS...BUT HEALTHY PRES FALLS AHEAD OF LOW WED AND HEALTHY PRES RISES ARRIVING BEHIND TROF PASSAGE WED NIGHT/THU MORNING MAY BE WHAT PUSHES WINDS TO GALE FORCE FOR A TIME. WINDS WILL THEN DIMINISH THU NIGHT/FRI. INCREASING WINDS ARE EXPECTED FOR THE WEEKEND AS LOW PRES TROF APPROACHES AND THEN MOVES ACROSS THE AREA. && .HYDROLOGY... ISSUED AT 416 AM EDT TUE APR 8 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN UPPER MICHIGAN HAS RIPENED AND WOULD EXPECT THE ABOVE NORMAL TEMPERATURES TODAY TO INCREASE SNOWMELT. COOLER TEMPERATURES ARRIVING ON TUESDAY (INCLUDING LOWS WELL BELOW FREEZING TUESDAY NIGHT) WILL LEAD TO REDUCED SNOWMELT DURING THAT PERIOD...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS OVER THE FIRST HALF OF THIS WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...SRF AVIATION...JLB MARINE...ROLFSON HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 AM EDT TUE APR 8 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 338 PM EDT MON APR 7 2014 A STRONG SHORTWAVE IS CURRENTLY LOCATED OVER SRN IL...WITH A 997MB SFC LOW OFFSET JUST TO THE E. AN INVERTED SFC TROUGH EXTENDS FROM THAT LOW TO NE OF LAKE SUPERIOR...WHICH IS AHEAD OF A WEAKENING SHORTWAVE NEAR DLH. AN AREAS OF RAIN SHOWERS HAS BEEN STEADILY WEAKENING AS IT MOVES INTO THE WRN CWA UNDER THE SHORTWAVE TO OUR W...WITH NO PRECIP OBSERVED OVER WRN UPPER MI FROM THIS PRECIP. IT DOES LOOK LIKE SOME LIGHT RAIN SHOWERS WILL MOVE NEAR IRONWOOD OVER THE NEXT FEW HOURS...BUT AMOUNTS ARE DIFFICULT TO DETERMINE GIVEN A DIMINISHING TREND ON RADAR AND LACK OF MODELS SHOWING PRECIP THERE. A FEW RAIN SHOWERS HAVE ALSO BEEN COMING AND GOING FROM NEAR IRON MOUNTAIN TO NEAR NEWBERRY THIS AFTERNOON...BUT NO SIGNIFICANT PRECIP SHOULD HAVE FALLEN IN THAT AREA. MODELS ARE HANDLING THE SRN/ERN SHOWERS POORLY...WITH SOME MODELS SHOWING SIGNIFICANT QPF AMOUNTS OVER AN INCH NEAR THE WI BORDER...BUT THOSE MODELS HAVE NOT HANDLED THE PRECIP WELL ALL DAY AND HAVE SFC DEW POINTS /AND THEREFORE INSTABILITY/ TOO HIGH. WENT MORE WITH THE LATEST HRRR RUNS THAT HAVE TRENDED DRIER FOR THAT AREA...SO ONLY HAVE SLIGHT CHANCE POPS INTO THIS EVENING THERE. AFTER THE WEAK SHORTWAVE TO OUR W AND ASSOCIATED WEAK SFC TROUGH MOVE THROUGH THIS EVENING...LOW LEVEL MOISTURE BEHIND THE TROUGH /AND FOG OVER WRN/CENTRAL LAKE SUPERIOR/ WILL COMBINE WITH INCREASING NNW LOW LEVEL FLOW TO PRODUCE SOME DRIZZLE/FREEZING DRIZZLE NEAR LAKE SUPERIOR. STILL NOT TOO CERTAIN ON COVERAGE/INTENSITY...BUT ENOUGH HIGH RES MODELS WERE SHOWING IT TO KEEP IN THE FORECAST WITH DECENT CONFIDENCE. DRIER LOW LEVEL AIR WILL MOVE IN TOMORROW ALONG WITH A SFC RIDGE...SO DRIZZLE WILL DIMINISH IN THE MORNING. HAVE HIGHS CLIMBING TO AROUND 50 OVER THE SCENTRAL...5-10 DEGREES COOLER THAN TODAY AS THE AIRMASS WILL BE COOLER /850MB TEMPS 8-9 DEGREES COLDER THAN TODAY/. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 416 AM EDT TUE APR 8 2014 AFTER A COOLER DAY TODAY...WEDNESDAY WILL TRANSITION BACK TO THE ABOVE NORMAL TEMPERATURES SEEN OVER THE LAST COUPLE OF DAYS. THIS IS DUE TO AN UPPER RIDGE CURRENTLY OVER THE WESTERN CONUS SHIFTING EAST INTO THE GREAT LAKES REGION FOR WEDNESDAY AND WEDNESDAY NIGHT. AS THIS RIDGE MOVES IN...EXPECT A STRONG AREA OF WARM AIR ADVECTION AND Q-VECTOR CONVERGENCE SHIFTING EAST-SOUTHEAST ALONG THE US/CANADIAN BORDER (AND ACROSS THE NORTHERN HALF OF THE CWA) LATE TONIGHT THROUGH EARLY WEDNESDAY AFTERNOON. FOR MUCH OF THE LAND CWA...WOULD EXPECT THERE TO JUST BE SOME PASSING MID CLOUDS. BUT THERE MAY BE ENOUGH MOISTENING IN THE LOWER LEVELS TO ALLOW SOME LIGHT SPRINKLES TO AFFECT THE KEWEENAW PENINSULA. OTHERWISE...THIS AREA OF FORCING WILL QUICKLY SHIFT THROUGH AND SHOULD LEAD TO A FILTERED SUNSHINE OVER THE AREA DUE TO HIGH CLOUDS AHEAD OF THE NEXT SYSTEM. STRONG WARMING IN THE LOWER LEVELS THROUGH THE DAY ON WEDNESDAY (850MB TEMPS RISING FROM -4C AT 06Z TO AT LEAST 6C AT 00Z THURSDAY) SHOULD LEAD TO ANOTHER WARM DAY ACROSS THE CWA. WILL CONTINUE TO SHOW HIGHS IN THE UPPER 50S AND LOWER 60S OVER THE WESTERN HALF OF THE CWA AND LOWER VALUES (40S) OVER THE EAST WITH THE SOUTHWEST WINDS OFF LAKE MICHIGAN. SPEAKING OF THOSE WINDS...THEY LOOK TO BE A LITTLE GUSTY IN THE AFTERNOON (15-25KTS) AND THAT WILL ALLOW THE DOWNSLOPE AREAS TO WARM AND LIMIT LAKE BREEZE COOLING. WHILE THE WARMING IS OCCURRING ON WEDNESDAY...A SURFACE LOW WILL BE SHIFTING EAST THROUGH FAR NORTHERN ONTARIO AND A COLD FRONT WILL STRETCH SOUTHWEST INTO THE UPPER MISSISSIPPI VALLEY. MODELS REMAIN CONSISTENT ON THE TIMING OF THIS COLD FRONT MOVING THROUGH THE CWA DURING THE OVERNIGHT HOURS WEDNESDAY NIGHT AND FOR THE FIRST PART OF THURSDAY MORNING. MODELS ARE INDICATING THE BEST FORCING ALONG THE FRONT TO DIVE TO THE SOUTHEAST THROUGH WISCONSIN...BUT WILL HOLD ONTO CHANCE POPS DUE TO THE EXPECTED EASTWARD MOVEMENT OF THE UPSTREAM SHOWERS. STEEP MID LEVEL LAPSE RATES AND SHOWALTER VALUES AROUND 0 COULD PRODUCE A RUMBLE OF THUNDER OVER WESTERN LAKE SUPERIOR AND HAVE ADDED A SLIGHT CHANCE TO THE FAR WEST. WITH THE SHORTWAVE WELL BEHIND THE FRONT AND ONLY A VERY THIN LINE OF MOISTURE...EXPECT QPF AMOUNTS TO STAY BELOW 0.15IN IN MOST LOCATIONS. MOST OF THESE SHOWERS SHOULD SHIFT OUT OF THE CWA BY THE AFTERNOON. TEMPERATURES ALOFT COOL SOME BEHIND THE FRONT...BUT STILL LOOK TO BE AROUND 0C TO -2C AT 850MB. THOSE TEMPS COMBINED WITH SUNSHINE BEHIND THE FRONT WILL YIELD HIGHS IN THE UPPER 40S TO MID 50S. WITH A HIGH PRESSURE RIDGE SLIDING THROUGH THE AREA ON THURSDAY NIGHT...DRY CONDITIONS ARE EXPECTED AND TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S. FRIDAY LOOKS TO BE DRY OVER MUCH OF THE CWA...BUT THERE ARE A COUPLE SUBTLE FEATURES TO NOTE. FIRST...A SECONDARY SURFACE TROUGH TRIES TO BRUSH THE NORTHEAST THIRD OF THE CWA FRIDAY MORNING...BUT IT DOESN/T LOOK LIKE IT WILL MAKE IT THAT FAR INTO LAKE SUPERIOR. SECOND...A WEAK SHORTWAVE AND ASSOCIATED SURFACE TROUGH LOOKS TO SHIFT EAST THROUGH UPPER MICHIGAN AND WISCONSIN FRIDAY AFTERNOON/ EVENING AND COULD KICK OFF A SHOWER OR TWO. GFS IS BY FAR THE STRONGEST WITH THE WAVE BUT MOISTURE SEEMS TO BE VERY LIMITED. WILL TREND POPS UP TO LOW END SLIGHT CHANCES FOR THE AFTERNOON/EVENING...BUT CONFIDENCE IS LOW. FOR THE WEEKEND...FOCUS IS ON TWO UPPER LEVEL FEATURES THAT WILL BE OVER THE WESTERN CONUS ON FRIDAY NIGHT...ONE NEAR SOUTHERN CALIFORNIA AND THE OTHER IN THE PACIFIC NORTHWEST. THE LEADING PIECES OF ENERGY ASSOCIATED WITH THESE WAVES WILL PUSH THE FIRST WAVE OF PRECIP ACROSS THE AREA ON SATURDAY. THIS PRECIP WILL BE ASSOCIATED WITH AN ELONGATED TROUGH STRETCHING NORTHEAST FROM THE CENTRAL/SOUTHERN ROCKIES. MODELS STILL SHOWING A WIDE VARIETY OF SOLUTIONS FOR THE LOCATION OF THE TROUGH WITH THE GFS/GEM FAST/SE ECMWF FARTHEST NORTHWEST. A GENERAL BLEND WILL WORK WELL AT THIS POINT FOR POPS (CHANCES)...MOVING INTO THE WESTERN CWA SATURDAY MORNING AND SHIFTING EAST OVER THE REST OF THE AREA IN THE AFTERNOON. THE LOCATION OF THE ELONGATED TROUGH HAS A INFLUENCE ON THE WEATHER FOR THE REGION FOR THE SECOND HALF OF THE WEEKEND AND INTO MONDAY. BY THAT POINT...THE TWO WAVES THAT ARE ALONG THE WEST COAST WILL HAVE MERGED OVER THE CENTRAL CONUS AND WILL BE SHIFTING EAST. THESE FEATURES WILL BE HELPED BY A THIRD DISTURBANCE THAT WILL DROP SOUTHEAST FROM CANADA. THE TIMING OF THESE THREE FEATURES AND HOW FAR EAST THEY END UP WILL DETERMINE PRECIP CHANCES (AND MEASURABLE SNOW POSSIBILITY) FOR PARTS OF THE CWA. AS HAS BEEN THE CASE FOR THE LAST COUPLE DAYS...THE GFS IS THE FARTHEST EAST AND THE ECMWF IS THE FARTHEST WEST WHILE THE 00Z GEM IS NOW SIMILAR TO . THE GFS. WITH THE PHASING OF SEVERAL SHORTWAVES...CONFIDENCE IN ANY ONE SOLUTION IS VERY LOW AND MODELS WILL BE HIGHLY VARIABLE OVER THE NEXT COUPLE DAYS. AT THIS POINT...WILL HAVE THE HIGHER CHANCE POPS OVER THE SOUTHEAST HALF OF THE CWA...WHERE A GENERAL CONSENSUS WOULD INDICATE PRECIP. WITH THE EXPECTED COLD AIR THAT WILL SPILL IN BEHIND THE TROUGH ON SUNDAY...WOULD EXPECT THE PRECIP TO TRANSITION TO SNOW AND THERE COULD BE SOME ACCUMULATION IF THE 12Z ECMWF IS CORRECT. IN ADDITION...THE LOW LEVEL COLD AIR SURGING IN AT THE SURFACE WITH THE NORTHERLY WINDS COULD PRODUCE A 6HR PERIOD OF FREEZING RAIN. WAY TO FAR OUT TO GET TOO EXCITED AT THAT POTENTIAL AT THIS POINT...BUT IT IS SOMETHING TO WATCH. THE FIRST HALF OF NEXT WEEK LOOKS TO BE BELOW NORMAL TEMPERATURE WISE ACROSS THE GREAT LAKES REGION...AS THE UPPER LEVEL PATTERN RESEMBLES THE ONE FROM MUCH OF THIS PAST WINTER. 850MB TEMPS DO LOOK TO FALL TOWARD -12C TO -17C FOR A SHORT PERIOD DURING THE FIRST HALF OF THE WORK WEEK AND THAT COULD LEAD TO HIGHS AROUND FEEZING ON TUESDAY. FOR THOSE THAT HAVE BEEN ENJOYING THE SPRING LIKE TEMPERATURES OVER THE LAST COUPLE OF DAYS...IT APPEARS THIS TROUGH WILL LIFT OUT OF THE AREA ON WEDNESDAY AND RETURN THE AREA BACK TO NORMAL TEMPERATURES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 132 AM EDT TUE APR 8 2014 LOW LEVEL MOISTURE AND FOG CURRENTLY OVER WRN LAKE SUPERIOR AND WRN UPPER MI WILL SHIFT SE ACROSS MUCH OF THE AREA OVERNIGHT...LEADING TO UPSLOPE LOW CLOUDS...FOG AND -DZ/-FZDZ AT ALL SITES. THERE IS UNCERTAINTY REGARDING THE EXTENT OF LOW CIGS AND VIS...BUT GIVEN THE TRENDS IN RECENT HRS OVER THE WEST...EXPECT THAT LIFR AND VLIFR CONDITIONS WILL LINGER AT CMX/IWD WHILE MAINLY MVFR DROPPING TO IFR CONDITIONS WILL PREVAIL AT SAW. THE LOW CIGS AND MVFR VSBY WILL IMPROVE DURING THE MORNING WITH VFR CONDITIONS EXPECTED BY EARLY AFTERNOON AS DRIER AIR MOVES INTO THE REGION. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 338 PM EDT MON APR 7 2014 AFTER A PERIOD OF LIGHT WINDS TODAY UNDER WEAK PRES GRADIENT...WINDS WILL PICK UP TONIGHT/TUE...MAINLY OVER ERN LAKE SUPERIOR...AS PRES GRADIENT TIGHTENS BTWN APPROACHING HIGH PRES RIDGE AND DEEPENING LOW PRES MOVING FROM THE OHIO VALLEY TO NEW ENGLAND. WINDS SHOULD REACH THE 15-25KT RANGE. WINDS DIMINISH TUE NIGHT AS HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEPENING LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS MAY REACH OR EXCEED 30KT AT SOME POINT WED/THU. WEAKENING PRES GRADIENT WILL BRING DIMINISHING WINDS FOR FRI. && .HYDROLOGY... ISSUED AT 416 AM EDT TUE APR 8 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN UPPER MICHIGAN HAS RIPENED AND WOULD EXPECT THE ABOVE NORMAL TEMPERATURES TODAY TO INCREASE SNOWMELT. COOLER TEMPERATURES ARRIVING ON TUESDAY (INCLUDING LOWS WELL BELOW FREEZING TUESDAY NIGHT) WILL LEAD TO REDUCED SNOWMELT DURING THAT PERIOD...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS OVER THE FIRST HALF OF THIS WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...TITUS LONG TERM...SRF AVIATION...JLB MARINE...TITUS HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
132 AM EDT TUE APR 8 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 338 PM EDT MON APR 7 2014 A STRONG SHORTWAVE IS CURRENTLY LOCATED OVER SRN IL...WITH A 997MB SFC LOW OFFSET JUST TO THE E. AN INVERTED SFC TROUGH EXTENDS FROM THAT LOW TO NE OF LAKE SUPERIOR...WHICH IS AHEAD OF A WEAKENING SHORTWAVE NEAR DLH. AN AREAS OF RAIN SHOWERS HAS BEEN STEADILY WEAKENING AS IT MOVES INTO THE WRN CWA UNDER THE SHORTWAVE TO OUR W...WITH NO PRECIP OBSERVED OVER WRN UPPER MI FROM THIS PRECIP. IT DOES LOOK LIKE SOME LIGHT RAIN SHOWERS WILL MOVE NEAR IRONWOOD OVER THE NEXT FEW HOURS...BUT AMOUNTS ARE DIFFICULT TO DETERMINE GIVEN A DIMINISHING TREND ON RADAR AND LACK OF MODELS SHOWING PRECIP THERE. A FEW RAIN SHOWERS HAVE ALSO BEEN COMING AND GOING FROM NEAR IRON MOUNTAIN TO NEAR NEWBERRY THIS AFTERNOON...BUT NO SIGNIFICANT PRECIP SHOULD HAVE FALLEN IN THAT AREA. MODELS ARE HANDLING THE SRN/ERN SHOWERS POORLY...WITH SOME MODELS SHOWING SIGNIFICANT QPF AMOUNTS OVER AN INCH NEAR THE WI BORDER...BUT THOSE MODELS HAVE NOT HANDLED THE PRECIP WELL ALL DAY AND HAVE SFC DEW POINTS /AND THEREFORE INSTABILITY/ TOO HIGH. WENT MORE WITH THE LATEST HRRR RUNS THAT HAVE TRENDED DRIER FOR THAT AREA...SO ONLY HAVE SLIGHT CHANCE POPS INTO THIS EVENING THERE. AFTER THE WEAK SHORTWAVE TO OUR W AND ASSOCIATED WEAK SFC TROUGH MOVE THROUGH THIS EVENING...LOW LEVEL MOISTURE BEHIND THE TROUGH /AND FOG OVER WRN/CENTRAL LAKE SUPERIOR/ WILL COMBINE WITH INCREASING NNW LOW LEVEL FLOW TO PRODUCE SOME DRIZZLE/FREEZING DRIZZLE NEAR LAKE SUPERIOR. STILL NOT TOO CERTAIN ON COVERAGE/INTENSITY...BUT ENOUGH HIGH RES MODELS WERE SHOWING IT TO KEEP IN THE FORECAST WITH DECENT CONFIDENCE. DRIER LOW LEVEL AIR WILL MOVE IN TOMORROW ALONG WITH A SFC RIDGE...SO DRIZZLE WILL DIMINISH IN THE MORNING. HAVE HIGHS CLIMBING TO AROUND 50 OVER THE SCENTRAL...5-10 DEGREES COOLER THAN TODAY AS THE AIRMASS WILL BE COOLER /850MB TEMPS 8-9 DEGREES COLDER THAN TODAY/. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 434 PM EDT MON APR 7 2014 LIGHT WINDS AND A MAINLY CLEAR SKY SHOULD RESULT IN COOLER TEMPS...ESPECIALLY OVER THE E HALF OF UPPER MI WHERE PW VALUES START THE EVENING NEAR 50 PERCENT OF NORMAL /0.2IN/. THE EXITING SFC RIDGE OVER THE CWA AT 06Z WEDNESDAY WILL BE QUICKLY REPLACED BY A WRAPPED UP LOW NEARING FROM CENTRAL CANADA. THE 978MB WILL SWING ACROSS ONTARIO WEDNESDAY NIGHT...DRAGGING A COLD FRONT ACROSS THE THE W HALF OF UPPER MI WEDNESDAY EVENING...AND E OVERNIGHT. STRONG GUSTY WINDS WILL BE POSSIBLE WITH THIS SYSTEM...BOTH AHEAD OF AND BEHIND THE FRONT. 850MB WINDS AROUND 40KTS WILL BE OVER UPPER MI FROM 00Z THURSDAY INTO LATE THURSDAY AFTERNOON. SIGNIFICANT MIXING OFF THE NAM INDICATES THE POTENTIAL FOR 30-35KT GUSTS OVER THE W HALF OF UPPER MI THROUGH MUCH OF THIS PERIOD. WILL NEED TO LOOK AT THIS FURTHER AS THE TIME NEARS. GALES MAY ALSO NEED TO BE ISSUED FOR LAKE SUPERIOR. THE SFC TROUGH WILL LINGER OVERHEAD THROUGH THURSDAY AS WEAK RIDGING TRIES TO PUSH N FROM THE MID MS VALLEY. EXPECT NW FLOW TO LINGER AT 500MB THROUGH FRIDAY. DESPITE THIS...SFC TEMPS SHOULD STILL BE ABLE TO REBOUND INTO THE 40S AND 50S FOR HIGHS FRIDAY. FRIDAY NIGHT ON... DUE TO THE LOW PROBABILITY...HAVE KEPT THE MENTION OF FREEZING DRIZZLE OUT OF THE HWO FOR OVERNIGHT FRIDAY NIGHT. THE BEST CHANCE WILL BE W OF A LINE FROM MQT TO ESC...WHERE TEMPERATURES WILL BE HOLDING NEAR FREEZING. OTHERWISE ACROSS THE CWA TEMPS SHOULD BE MAINLY ABOVE FREEZING. ANOTHER REASON TO KEEP THE MENTION OUT IS THE FACT THAT OUR CURRENT TEMP FCST IS ON THE LOW END OF GUIDANCE...INCREASING THE UNCERTAINTY. THIS LOW PROBABILITY PRECIP WILL BE OUT AHEAD OF A SFC LOW ORGANIZING ACROSS THE PLAINS STATES FRIDAY NIGHT AND SATURDAY. AN ELONGATED AREA OF LOW PRESSURE SHOULD STRETCH FROM WI THROUGH N TX AT 06Z SUNDAY. THE 500MB TROUGH OVER THE PLAINS STATES AT 12Z SUNDAY WILL CROSS UPPER MI THIS WEEKEND THROUGH MONDAY...WITH THE SFC LOW REMAINING MAINLY TO OUR S AND E /STRETCHING FROM S QUEBEC THROUGH MO AROUND DAYBREAK MONDAY. THERE IS SOME TIMING ISSUES...PARTICULARLY FROM SATURDAY NIGHT ON WITH THE GFS ON THE QUICK SIDE. EVEN WITH THE DIFFERENCES THIS SYSTEM SHOULD BRING ABOUT THE BEST CHANCE OF PRECIP FOR THE ENTIRE PERIOD...ESPECIALLY FOR S CENTRAL UPPER MI. RAIN WILL BE THE DOMINANT WEATHER TYPE UNTIL THE LOW SHIFTS E AND TRANSITIONS TO MAINLY S SUNDAY NIGHT. COLD FOR THE EXTENDED...JUST BEYOND THIS TIME PERIOD. THE 12Z ECMWF BRINGS 850MB TEMPS BACK INTO THE -15 TO -18C RANGE MONDAY NIGHT INTO TUESDAY. THE GOOD NEWS FOR THOSE WHO ENJOY A LITTLE MORE SEASONAL WEATHER...THE ECMWF DOES BRING BACK NEGATIVE SINGLE DIGIT 850MB TEMPS BACK IN FOR TUESDAY NIGHT. THE 12Z GFS SHOWS A SIMILAR STORY...BUT A COUPLE OF DEGREES WARMER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 132 AM EDT TUE APR 8 2014 LOW LEVEL MOISTURE AND FOG CURRENTLY OVER WRN LAKE SUPERIOR AND WRN UPPER MI WILL SHIFT SE ACROSS MUCH OF THE AREA OVERNIGHT...LEADING TO UPSLOPE LOW CLOUDS...FOG AND -DZ/-FZDZ AT ALL SITES. THERE IS UNCERTAINTY REGARDING THE EXTENT OF LOW CIGS AND VIS...BUT GIVEN THE TRENDS IN RECENT HRS OVER THE WEST...EXPECT THAT LIFR AND VLIFR CONDITIONS WILL LINGER AT CMX/IWD WHILE MAINLY MVFR DROPPING TO IFR CONDITIONS WILL PREVAIL AT SAW. THE LOW CIGS AND MVFR VSBY WILL IMPROVE DURING THE MORNING WITH VFR CONDITIONS EXPECTED BY EARLY AFTERNOON AS DRIER AIR MOVES INTO THE REGION. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 338 PM EDT MON APR 7 2014 AFTER A PERIOD OF LIGHT WINDS TODAY UNDER WEAK PRES GRADIENT...WINDS WILL PICK UP TONIGHT/TUE...MAINLY OVER ERN LAKE SUPERIOR...AS PRES GRADIENT TIGHTENS BTWN APPROACHING HIGH PRES RIDGE AND DEEPENING LOW PRES MOVING FROM THE OHIO VALLEY TO NEW ENGLAND. WINDS SHOULD REACH THE 15-25KT RANGE. WINDS DIMINISH TUE NIGHT AS HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEPENING LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS MAY REACH OR EXCEED 30KT AT SOME POINT WED/THU. WEAKENING PRES GRADIENT WILL BRING DIMINISHING WINDS FOR FRI. && .HYDROLOGY... ISSUED AT 338 PM EDT MON APR 7 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN UPPER MICHIGAN HAS RIPENED AND WOULD EXPECT THE ABOVE NORMAL TEMPERATURES TODAY TO INCREASE SNOWMELT. COOLER TEMPERATURES ARRIVING ON TUESDAY (INCLUDING LOWS WELL BELOW FREEZING TUESDAY NIGHT) WILL LEAD TO REDUCED SNOWMELT DURING THAT PERIOD...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS OVER THE FIRST HALF OF THIS WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...TITUS LONG TERM...KF AVIATION...JLB MARINE...TITUS HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 AM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS MORNING. SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT THROUGH WEDNESDAY NIGHT. MEANWHILE AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 255 AM TUESDAY... TODAY: THE SURFACE COLD FRONT THIS MORNING IS CURRENTLY MOVING ACROSS THE MOUNTAINS OF NC. EXPECT THE SURFACE FRONT WILL CONTINUE TO SLOWLY SHIFT EASTWARD ACROSS CENTRAL THIS MORNING...AS THE FULL LATITUDE TROUGH ALOFT TO OUR WEST CONTINUES TO SHIFT EASTWARD. EXPECT THE MAIN SURFACE FRONT SHOULD BE TO THE EAST OF CENTRAL NC BY EARLY AFTERNOON AT THE LATEST. HOWEVER... WITH THE DEEP MOIST SOUTHWESTERLY MID/UPPER LEVEL FLOW AND PW`S STILL AROUND 1.5+ INCHES THIS MORNING ACROSS OUR EAST EXPECT WE WILL SEE SOME SHOWERS AND PERHAPS OF AN ISOLATED RUMBLE OF THUNDER FOR LOCATIONS IN THE SANDHILLS AND COASTAL PLAIN. 0-6KM DEEP LAYER SHEAR IS IMPRESSIVE THIS MORNING IN THE 60 TO 80 KT RANGE ACROSS THE CWA. HOWEVER... GIVEN THE TIME OF MORNING AND RAINFALL FRONT EARLIER TODAY WE REMAIN RATHER STABLE AT THE SURFACE. THUS.. VERY LITTLE IF ANY SURFACE INSTABILITY TO WORK WITH WE ARE NOT EXPECTED MUCH OF A SEVERE THREAT. HOWEVER... THE LATEST RAP DID SHOW MAYBE A 100 J/KG OF MLCAPE DEVELOPING LATER THIS MORNING AS THE SURFACE FRONT APPROACHES POINTS GENERALLY ALONG AN EAST OF RALEIGH. THUS... WE CANT RULE OUT A STRONG WIND GUST OR TWO ACROSS EASTERN PORTIONS OF THE AREA... BUT THE THREAT WILL REMAIN QUITE SMALL AT BEST. WITH THE DEEP TROUGH ALOFT EXPECTED TO REMAIN TO THE WEST OF THE AREA TODAY... WE SHOULD SEE A GOOD BIT OF MID AND HIGH LEVEL MOISTURE TO START THE DAY EVEN AFTER THE SURFACE FRONT PUSHES TO THE EAST. IN FACT WE MAY EVEN SEE SOME LINGER LOW LEVEL MOISTURE ACROSS OUR FAR EAST/SOUTHEAST REACHES OF THE CWA BEHIND THE FRONT TODAY IN ASSOCIATED WITH A LINGERING SURFACE TROUGH. WHILE WE DO NOT EXPECT ANY PRECIP AFTER 18Z OR SO ACROSS OUR EAST/SOUTHEAST (OR ANYWHERE IN THE CWA)... WE MAY SEE MOSTLY CLOUDY SKIES LINGERING INTO LATE IN THE DAY... WITH LOCATIONS ACROSS THE WESTERN PIEDMONT PERHAPS SEE THE MOST SUN TODAY. WRT HIGH TEMPS.... STILL THINK WE WILL SEE HIGH TEMPS RANGE FROM THE MID 60S NW TO THE LOWER 70S SOUTH AND EAST... AS WE WILL HAVE HAVE A DOWNSLOPE FLOW... PLUS THICKNESS VALUES ARE NOT EXPECTED TO CRASH. TONIGHT AND WEDNESDAY: EXPECT A SERIES OF EMBEDDED S/W`S IN THE DEEP TROUGH ALOFT WILL CROSS THE REGION AS THE DEEP TROUGH ITSELF SHIFTS EASTWARD AND ACROSS THE AREA THROUGH WEDNESDAY. THIS WILL RESULT IN PERIODS OF PARTLY TO MOSTLY CLOUDY/CLOUDY SKIES. EXPECT WE WILL GENERALLY REMAIN DRY THOUGH. HOWEVER... WITH 500 MB HEIGHTS FALLING SOME 150 METERS BETWEEN NOW AND WEDNESDAY MORNING WE WILL SEE OUR INSTABILITY ALOFT INCREASE... WITH POSSIBLY SOME SHOWERS DEVELOPING WEDNESDAY AFTERNOON IN ASSOCIATION WITH THE FINAL PASSING SHORTWAVE. FOR NOW WILL LEAVE POPS IN THE SLIGHT CHANCE CATEGORY AS MODEL SOUNDING ARE QUITE DRY AND MODEL GUIDANCE HAS TRENDED DRIER. EXPECT LOWS WEDNESDAY MORNING WILL GENERALLY BE IN THE 40S... WITH HIGHS WEDNESDAY AFTERNOON IN THE 60S. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 315 AM TUESDAY... WEDNESDAY NIGHT AND THURSDAY... A S/W RIDGE IN THE MID-UPPER LEVELS AND ITS ATTENDANT SFC HIGH WILL CROSS CENTRAL NC WEDNESDAY NIGHT INTO THURSDAY. THIS WEATHER SYSTEM WILL PROVIDE PLENTY OF DRY STABLE AIR LEADING TO CLEAR SKIES WEDNESDAY NIGHT AND INTO THURSDAY. SFC WINDS WILL DECOUPLE EARLY WEDNESDAY EVENING...ALLOWING TEMPS TO COOL QUICKLY. LATEST MOS GUIDANCE HAS COME IN A COUPLE OF DEGREES WARMER THAN PREVIOUS RUN. NOT READY TO BUY INTO THIS YET AS SFC DEWPOINTS UNDERNEATH THE HIGH AT THIS TIME ARE IN THE 20S TO LOWER 30S. WENT WITH MIN TEMPS UPPER 30S NORTH-NW TO LOWER 40S SOUTH. POTENTIAL FOR LIGHT FROST DOES NOT LOOK AS GOOD AS IT DID 24-48 HOURS AGO. HOWEVER STILL BELIEVE THAT A SPOT OR TWO ACROSS THE NORTHERN PIEDMONT MAY DIP BRIEFLY INTO THE MID 30S TO ALLOW FROST FORMATION BUT LIMITED NATURE OF THE LIGHT FROST SUGGEST THAT AN ADVISORY WOULD PROBABLY BE OVERKILL. SFC HIGH WILL SCOOT QUICKLY EAST THURSDAY WITH A WARM BREEZY SW SFC WIND DEVELOPING IN ITS WAKE. THIS LOW LEVEL FLOW WILL ADVECT WARMER AIR INTO CENTRAL NC. AGAIN...MOS GUIDANCE HAS TRENDED WARMER COMPARED TO PREVIOUS RUNS. PREFER TO WAIT TO SEE IF THIS TREND HOLDS AS MODEL LOW LEVEL THICKNESSES SUPPORT MAX TEMPS 3-5 DEGREES COOLER. FOR NOW WILL FAVOR MAX TEMPS ON THE COOL END OF MOS GUIDANCE... VARYING FROM NEAR 70 ACROSS THE NORTH TO THE LOWER 70S SOUTH. THURSDAY NIGHT AND FRIDAY...WARM AND DRY CONDITIONS WILL PERSIST AS FLOW ALOFT WILL REMAIN ZONAL AND LOW LEVEL SW FLOW CONTINUES WITH A SFC HIGH ANCHORED OFF THE SE U.S. COAST. THE MODIFYING AIR MASS WILL SUPPORT MIN TEMPS THURSDAY NIGHT ABOUT 10 DEGREES WARMER THAN THE PREVIOUS NIGHT (UPPER 40S TO AROUND 50). MAX TEMPS FRIDAY AFTERNOON REBOUND WELL INTO THE 70S...APPROACHING 80 IN THE FAR SOUTH-SE. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 315 AM TUESDAY... FRIDAY NIGHT AND SATURDAY...A S/W IN THE NORTHERN STREAM WILL CROSS THE GREAT LAKES AND NEW ENGLAND. THIS FEATURE WILL DRAG A SFC COLD FRONT TOWARD CENTRAL NC BY LATE FRIDAY AND FRIDAY NIGHT...CROSSING INTO OUR REGION EARLY SATURDAY BEFORE DISSIPATING. BEST/DEEPEST MOISTURE AND BETTER LIFT WILL OCCUR WELL TO OUR NORTH-NORTHWEST. THE FRONT LOSES A LOT OF ITS UPPER SUPPORT BY THE TIME IT REACHES CENTRAL NC LATE FRIDAY NIGHT INTO EARLY SATURDAY. IN ADDITION...MOISTURE WILL BE FAIRLY LIMITED. PLAN TO MAINTAIN A SLIGHT CHANCE POP ACROSS THE FAR NORTH FRIDAY NIGHT AND A SLIGHT CHANCE POP MOST PLACES SATURDAY THOUGH IT APPEARS THAT S/W RIDGING ALOFT WILL TAKE HOLD BY SATURDAY AFTERNOON. SUBSIDENCE ASSOCIATED WITH THIS FEATURE SHOULD LIMIT SHOWER DEVELOPMENT. ADDITIONAL CLOUD COVER FRIDAY NIGHT AND A LIGHT SOUTH WIND WILL RESULT IN MILD OVERNIGHT CONDITIONS. A MIX OF CLOUDS AND SUN SATURDAY AND VERY LITTLE CHANGE IN THE AIR MASS SUPPORTS MAX TEMPS IN THE MID-UPPER 70S. SUNDAY INTO MONDAY...UPPER LEVEL FLOW WILL GRADUALLY BACK TO THE SW IN ADVANCE OF A DEVELOPING/STRENGTHENING L/W TROUGH THAT WILL APPROACH FROM THE WEST. A S/W RIDGE OVER SE U.S. SUNDAY WILL MAINTAIN WARM AND MOSTLY DRY CONDITIONS. CANNOT RULE OUT AN ISOLATED SHOWER LATE SUNDAY AFTERNOON AS NEAR SFC FLOW BECOMES SELY...LEADING TO A WEAK UPSLOPE COMPONENT AND SOME MOISTURE ADVECTION OFF THE ATLANTIC. SHOWER THREAT APPEARS TOO MINIMAL TO MENTION IN FORECAST AT THIS TIME. SHOWER THREAT WILL GRADUALLY INCREASE MONDAY AS DEEP/STRENGTHENING SLY FLOW WILL ADVECT GULF MOISTURE INTO CENTRAL NC. THIS MOIST AND SLIGHTLY UNSTABLE AIR MASS MAY SUPPORT A FEW SHOWERS BY MONDAY AFTERNOON DUE TO SFC HEATING. BETTER DYNAMICS/SUPPORT ALOFT WILL OCCUR MONDAY NIGHT INTO TUESDAY FOR A GREATER THREAT FOR SHOWERS. TEMPS SUNDAY AND MONDAY EXPECTED TO REMAIN MILD WITH MAX TEMPS AVERAGING 5-6 DEGREES ABOVE NORMAL. EXPECT MIN TEMPS IN THE 50S WITH AFTERNOON TEMPS IN THE 75-80 DEGREE RANGE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 150 AM TUESDAY... 24 HOUR TAF PERIOD: A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING. AHEAD OF THIS FRONT EXPECT GENERALLY IFR TO MVFR CONDITIONS WILL DEVELOP/CONTINUE... WITH EVEN SOME LIFR CONDITIONS POSSIBLY AT KGSO/KINT. IN ADDITION ISOLATED SHOWERS WILL BE POSSIBLE UNTIL THE FRONT MOVES ACROSS A GIVE LOCATION... ALONG WITH THE THREAT OF A FEW WIND GUSTS OF UP TO 20 KTS TO EVEN 30 KTS IN SHOWERS. EXPECT THE FRONT WILL MOVE THROUGH THE TRIAD REGION IN THE 09-11Z TIME FRAME.... KRDU AROUND 12Z AND KFAY/KRWI 13-16Z. WE MAY SEE SOME OF THE LOWER LEVEL MOISTURE LINGERING AT KFAY AND KRWI AS A LINGERING SURFACE TROUGH IS EXPECTED TO STALL ACROSS OUR FAR EASTERN/SOUTHEASTERN REACHES OF CENTRAL NC. THUS... WILL NOT SHOW CONDITIONS BECOMING VFR AT KFAY AND KRWI UNTIL 18Z... WITH EVEN A SMALL THREAT OF SOME LINGERING SHOWERS TOO. OTHERWISE... EXPECT WINDS WILL SWING AROUND TO MORE OF A WNW TO NW DIRECTION BEHIND THE FRONT... WITH WINDS BECOMING NORTHERLY TONIGHT. OUTLOOK: AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA WEDNESDAY... WITH POSSIBLY SOME VERY LIGHT SHOWERS. HOWEVER... AT THIS TIME EXPECT VFR CONDITIONS ARE EXPECTED ON WEDNESDAY AS MODELS HAVE TREND A BIT DRIER. OTHERWISE... MAINLY VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BSD/KCP NEAR TERM...BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...BSD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS MORNING. SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT THROUGH WEDNESDAY NIGHT. MEANWHILE AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 255 AM TUESDAY... TODAY: THE SURFACE COLD FRONT THIS MORNING IS CURRENTLY MOVING ACROSS THE MOUNTAINS OF NC. EXPECT THE SURFACE FRONT WILL CONTINUE TO SLOWLY SHIFT EASTWARD ACROSS CENTRAL THIS MORNING...AS THE FULL LATITUDE TROUGH ALOFT TO OUR WEST CONTINUES TO SHIFT EASTWARD. EXPECT THE MAIN SURFACE FRONT SHOULD BE TO THE EAST OF CENTRAL NC BY EARLY AFTERNOON AT THE LATEST. HOWEVER... WITH THE DEEP MOIST SOUTHWESTERLY MID/UPPER LEVEL FLOW AND PW`S STILL AROUND 1.5+ INCHES THIS MORNING ACROSS OUR EAST EXPECT WE WILL SEE SOME SHOWERS AND PERHAPS OF AN ISOLATED RUMBLE OF THUNDER FOR LOCATIONS IN THE SANDHILLS AND COASTAL PLAIN. 0-6KM DEEP LAYER SHEAR IS IMPRESSIVE THIS MORNING IN THE 60 TO 80 KT RANGE ACROSS THE CWA. HOWEVER... GIVEN THE TIME OF MORNING AND RAINFALL FRONT EARLIER TODAY WE REMAIN RATHER STABLE AT THE SURFACE. THUS.. VERY LITTLE IF ANY SURFACE INSTABILITY TO WORK WITH WE ARE NOT EXPECTED MUCH OF A SEVERE THREAT. HOWEVER... THE LATEST RAP DID SHOW MAYBE A 100 J/KG OF MLCAPE DEVELOPING LATER THIS MORNING AS THE SURFACE FRONT APPROACHES POINTS GENERALLY ALONG AN EAST OF RALEIGH. THUS... WE CANT RULE OUT A STRONG WIND GUST OR TWO ACROSS EASTERN PORTIONS OF THE AREA... BUT THE THREAT WILL REMAIN QUITE SMALL AT BEST. WITH THE DEEP TROUGH ALOFT EXPECTED TO REMAIN TO THE WEST OF THE AREA TODAY... WE SHOULD SEE A GOOD BIT OF MID AND HIGH LEVEL MOISTURE TO START THE DAY EVEN AFTER THE SURFACE FRONT PUSHES TO THE EAST. IN FACT WE MAY EVEN SEE SOME LINGER LOW LEVEL MOISTURE ACROSS OUR FAR EAST/SOUTHEAST REACHES OF THE CWA BEHIND THE FRONT TODAY IN ASSOCIATED WITH A LINGERING SURFACE TROUGH. WHILE WE DO NOT EXPECT ANY PRECIP AFTER 18Z OR SO ACROSS OUR EAST/SOUTHEAST (OR ANYWHERE IN THE CWA)... WE MAY SEE MOSTLY CLOUDY SKIES LINGERING INTO LATE IN THE DAY... WITH LOCATIONS ACROSS THE WESTERN PIEDMONT PERHAPS SEE THE MOST SUN TODAY. WRT HIGH TEMPS.... STILL THINK WE WILL SEE HIGH TEMPS RANGE FROM THE MID 60S NW TO THE LOWER 70S SOUTH AND EAST... AS WE WILL HAVE HAVE A DOWNSLOPE FLOW... PLUS THICKNESS VALUES ARE NOT EXPECTED TO CRASH. TONIGHT AND WEDNESDAY: EXPECT A SERIES OF EMBEDDED S/W`S IN THE DEEP TROUGH ALOFT WILL CROSS THE REGION AS THE DEEP TROUGH ITSELF SHIFTS EASTWARD AND ACROSS THE AREA THROUGH WEDNESDAY. THIS WILL RESULT IN PERIODS OF PARTLY TO MOSTLY CLOUDY/CLOUDY SKIES. EXPECT WE WILL GENERALLY REMAIN DRY THOUGH. HOWEVER... WITH 500 MB HEIGHTS FALLING SOME 150 METERS BETWEEN NOW AND WEDNESDAY MORNING WE WILL SEE OUR INSTABILITY ALOFT INCREASE... WITH POSSIBLY SOME SHOWERS DEVELOPING WEDNESDAY AFTERNOON IN ASSOCIATION WITH THE FINAL PASSING SHORTWAVE. FOR NOW WILL LEAVE POPS IN THE SLIGHT CHANCE CATEGORY AS MODEL SOUNDING ARE QUITE DRY AND MODEL GUIDANCE HAS TRENDED DRIER. EXPECT LOWS WEDNESDAY MORNING WILL GENERALLY BE IN THE 40S... WITH HIGHS WEDNESDAY AFTERNOON IN THE 60S. && .SHORT TERM /WEDNESDAY NIGHT/... AS OF 245 PM MONDAY... A MID-LEVEL TROUGH MOVES THROUGH WEDNESDAY...WITH HEIGHT RISES TAKING PLACE WEDNESDAY NIGHT. A WEAK SURFACE TROUGH IS FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA UNDER BROAD SURFACE HIGH PRESSURE...WITH GENERAL SUBSIDENCE ALSO FORECAST OVER THE AREA. A MODEST 850MB THETA-E RIDGE IS IN PLACE OVER CENTRAL NORTH CAROLINA WHILE K INDICES FALL LATE IN THE DAY FROM NEAR 20 TO AROUND ZERO BY NIGHTFALL. JET SUPPORT BY WEDNESDAY IS FORECAST TO BE EAST OF THE AREA WITH ONLY MODEST 850MB LIFT FORECAST BY THE GFS. LIFTED INDICES FALL TO NEAR ZERO IN THE AFTERNOON...AND WHILE MLCAPE IN THE LOWEST KM HARDLY REGISTERS ON THE GFS...1000-500MB LAPSE RATES ARE QUITE STEEP EARLY WEDNESDAY AFTERNOON...AT OR SLIGHTLY GREATER THAN 7.5C/KM. BUFR SOUNDINGS SHOW THE CAP ALOFT IS WEAK...INCREASING AROUND 700MB BY 00Z...BUT FOR THE AFTERNOON UNTIL THEN...IN THE COOL TROUGH ALOFT...AN ISOLATED SHOWER IS POSSIBLE. INCREASING STABILITY WITH AN INCREASING CAP ALOFT DURING WEDNESDAY NIGHT SHOULD KEEP ANY SHOWER DIURNAL IN NATURE. FORTUNATELY...DESPITE THE LOW-LEVEL DRY AIR AND THE STEEP LAPSE RATES...WINDS ALOFT TO 700MB ARE MAINLY AT OR BELOW 25KT...AND MID-LEVEL MOISTURE IS LIMITED IN VOLUME...SO THE POTENTIAL FOR ANY VERY GUSTY WIND WITH A SHOWER IS CURRENTLY LOW. 1000-850MB THICKNESSES FOR WEDNESDAY SUPPORT HIGHS AT LEAST IN THE MID 60S...AND WITH THE COOL TROUGH OVERHEAD WILL LEAN TOWARD THE COOLER MAV GUIDANCE FOR HIGHS ON WEDNESDAY. OVERNIGHT WEDNESDAY NIGHT...GFS BUFR SOUNDINGS SHOW DECOUPLING SHOULD TAKE PLACE...AND THE AIR MASS BECOMES RATHER DRY THROUGH THE COLUMN ESPECIALLY NORTH OF KFAY. UNDER THE SURFACE RIDGE LATE AT NIGHT...GOOD RADIATIONAL COOLING POTENTIAL EXISTS...AND HAVE CONTINUED A TREND COOLER THAN GUIDANCE FOR LOWS...MOSTLY 37 TO 42. IF THIS TREND CONTINUES OR REMAINS EXPECTED...PATCHY FROST WILL BE POSSIBLE PARTICULARLY OVER SOME AREAS ALONG AND NORTH OF ABOUT U.S. 64 AND COULD BE ADDED TO LATER FORECASTS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 245 PM MONDAY... THE LONG-TERM PART OF THE FORECAST WILL FEATURE A SHORTWAVE RIDGE MOVING THROUGH CENTRAL NORTH CAROLINA THURSDAY...FOLLOWED BY INCREASING TROUGHINESS ALOFT FRIDAY AND SATURDAY AS A COLD FRONT MOVES SOUTH TOWARD THE AREA. THE GFS IS WEAKER THAN THE ECMWF WITH THE WAVE ALOFT AND THE FRONT...THOUGH BOTH MODELS...IN ADVANCE OF THE FRONT MOVING INTO CENTRAL NORTH CAROLINA...INCREASE SURFACE RIDGING WEST OVER THE GULF SLIGHTLY SUCH THAT AVAILABLE MOISTURE AND CONVERGENCE MAY DIMINISH AS THE FRONT MOVES SOUTH. REGARDLESS OF THE STRENGTH OF THE UPPER-LEVEL FEATURES...BOTH MODELS SUPPORT WEAKENING OF THE FRONT SO THAT PRECIPITATION CHANCES MAY BE LOW AS THE FRONT MOVES THROUGH. THURSDAY THROUGH FRIDAY DURING THE DAY WILL REMAIN DRY...AND WILL RETAIN THE SMALL CHANCES FOR SHOWERS FOR FRIDAY NIGHT AND INTO SATURDAY FOR NOW AS THE FRONT APPROACHES. BY SATURDAY NIGHT...SUBSIDENCE IN THE WAKE OF WHATEVER IS LEFT OF THE FRONT AND DRIER AIR FORECAST BY THE LONG-TERM GUIDANCE WILL KEEP CHANCES BELOW SLIGHT...CONTINUING THROUGH SUNDAY UNDER SURFACE HIGH PRESSURE. CURRENTLY...AS THE SURFACE HIGH RETREATS MONDAY...AVAILABLE MOISTURE SHOULD INCREASE ALONG WITH THE CHANCES FOR PRECIPITATION. THE ECMWF IS SLOWER THAN THE GFS DUE TO A DEEPER UPPER LOW AS A RESULT OF SOME PHASING OF MODERATE WAVES IN THE NORTHERN AND SOUTHERN STREAMS... WHILE THE GFS IS MORE PROGRESSIVE...INTRODUCING GOOD QPF INTO CENTRAL NORTH CAROLINA DURING THE DAY MONDAY. EVEN THE ECMWF...WITH A FLOW OFF OF THE ATLANTIC...SUGGESTS THE POTENTIAL FOR A SHOWER OR TWO MONDAY...THOUGH WITH BETTER CHANCES HOLDING OFF UNTIL JUST BEYOND THIS LONG-TERM FORECAST PERIOD. THE BEST COURSE OF ACTION CURRENTLY WILL BE TO FOLLOW A CONSENSUS APPROACH WITH SLIGHT CHANCES FOR SHOWERS MONDAY AND GENERAL CHANCES FOR SHOWERS MONDAY NIGHT. DESPITE SYNOPTIC-SCALE DIFFERENCES IN PARTS OF THIS FORECAST PERIOD...THE MOS GUIDANCE FROM BOTH THE MEX AND MEE ARE VERY SIMILAR AND ALSO FAIRLY SIMILAR TO EXPECTATIONS FOR HIGHS BASED UPON 1000- 850MB THICKNESSES. HIGH TEMPERATURES WILL BE FORECAST AROUND 70 THURSDAY AND MOSTLY IN THE MID 70S TO NEAR 80 FOR THE REST OF THIS PART OF THE FORECAST PERIOD. OVERNIGHT LOWS MOSTLY IN THE MID TO UPPER 40S THURSDAY NIGHT...AROUND 50 TO THE MID 50S FRIDAY AND SATURDAY NIGHTS...THEN GRADUALLY WARMING TO LOWS TO AROUND 60 MONDAY NIGHT BASED ON THE CURRENT TIMING OF THE FRONT MOVING THEN TOWARD CENTRAL NORTH CAROLINA. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 150 AM TUESDAY... 24 HOUR TAF PERIOD: A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING. AHEAD OF THIS FRONT EXPECT GENERALLY IFR TO MVFR CONDITIONS WILL DEVELOP/CONTINUE... WITH EVEN SOME LIFR CONDITIONS POSSIBLY AT KGSO/KINT. IN ADDITION ISOLATED SHOWERS WILL BE POSSIBLE UNTIL THE FRONT MOVES ACROSS A GIVE LOCATION... ALONG WITH THE THREAT OF A FEW WIND GUSTS OF UP TO 20 KTS TO EVEN 30 KTS IN SHOWERS. EXPECT THE FRONT WILL MOVE THROUGH THE TRIAD REGION IN THE 09-11Z TIME FRAME.... KRDU AROUND 12Z AND KFAY/KRWI 13-16Z. WE MAY SEE SOME OF THE LOWER LEVEL MOISTURE LINGERING AT KFAY AND KRWI AS A LINGERING SURFACE TROUGH IS EXPECTED TO STALL ACROSS OUR FAR EASTERN/SOUTHEASTERN REACHES OF CENTRAL NC. THUS... WILL NOT SHOW CONDITIONS BECOMING VFR AT KFAY AND KRWI UNTIL 18Z... WITH EVEN A SMALL THREAT OF SOME LINGERING SHOWERS TOO. OTHERWISE... EXPECT WINDS WILL SWING AROUND TO MORE OF A WNW TO NW DIRECTION BEHIND THE FRONT... WITH WINDS BECOMING NORTHERLY TONIGHT. OUTLOOK: AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA WEDNESDAY... WITH POSSIBLY SOME VERY LIGHT SHOWERS. HOWEVER... AT THIS TIME EXPECT VFR CONDITIONS ARE EXPECTED ON WEDNESDAY AS MODELS HAVE TREND A BIT DRIER. OTHERWISE... MAINLY VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BSD/KCP NEAR TERM...BSD SHORT TERM...DJF LONG TERM...DJF AVIATION...BSD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
157 AM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS MORNING. SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT THROUGH WEDNESDAY NIGHT. MEANWHILE AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE ACROSS THE AREA ON WEDNESDAY. WITH HIGH PRESSURE EXPECTED TO BUILD EAST TOWARD THE REGION AND EVENTUALLY SETTLE OVERHEAD BY THURSDAY. && .NEAR TERM /THROUGH TUESDAY NIGHT/... AS OF 950 PM MONDAY... REGIONAL SURFACE ANALYSIS IS RATHER COMPLICATED THIS EVENING...WITH A LINGERING TRUE WEDGE FRONT ACROSS THE NORTHWEST PIEDMONT...A RETREATING WARM FROM SLOWLY PENETRATING INTO THE PIEDMONT...A CONVECTIVELY ENHANCED FRONTAL ZONE ALONG THE COAST...AND THE SYNOPTIC COLD FRONT MOVING THROUGH THE TN VALLEY. CURRENTLY...ALL APPRECIABLE INSTABILITY IS CONFINED TO THE COASTAL AREAS...WITH JUST AREAS OF LIGHT TO MODERATE RAIN MOVING NORTHEAST ACROSS THE EASTERN PIEDMONT AND COASTAL PLAIN. REGIONAL RADAR SUGGESTS THIS WILL CONTINUE FOR THE NEXT FEW HOURS...WHILE THE SYNOPTIC COLD FRONT MAKES ITS WAY ACROSS THE MOUNTAINS. THIS BIG QUESTION FOR THE OVERNIGHT PERIOD IS WHETHER OR NOT THERE WILL BE ANY RENEWED DEVELOPMENT ALONG OR AHEAD OF THE FRONT AS IT PUSHES EAST INTO A SLIGHTLY BETTER THERMODYNAMIC ENVIRONMENT....WHERE THE LATEST RAP RUNS SHOW 300-400 J/KG MLCAPE...AIDED BY A POCKET STEEPENING MID- LEVEL LAPSE RATES...REDEVELOPING OVER THE COASTAL PLAIN AFTER MIDNIGHT. FORCING FOR ACCENT ALONG THE COLD FRONT WILL BE AIDED BY INCREASING HEIGHT FALLS ALOFT AS THE UPPER TROUGH AXIS BEGINS TO MAKE A MORE AGGRESSIVE PUSH EAST. HRRR RUNS HAVE YET TO SHOW ANY REDEVELOPMENT...BUT THERE IS A NARROW LINE OF CONVECTION CURRENTLY DEVELOPING OVER NORTHERN GEORGIA. SHOWERS ARE ALSO KICKING UP OVER UPSTATE SC IN WHAT APPEARS TO BE WEAK WARM ADVECTION ALONG THE RETREATING WARM FRONT. DRYING MID-LEVEL AIR ANALYZED AT 700MB SHOULD KEEP THE OVERALL COVERAGE OF SHOWERS/STORM LIMITED...BUT IT SEEMS PLAUSIBLE THAT AN UPWARD TREND IN CONVECTION IS STILL POSSIBLE OVERNIGHT...EITHER WITH THE SHOWERS MOVING OUT OF SC...OR WITH A FORCED LINE OF SHALLOW CONVECTION LATER TONIGHT. FOR THE FORECASTS UPDATE...WILL MAINTAIN CHANCE POPS OVER THE NORTHWEST PIEDMONT...WITH LIKELY POPS TO THE EAST. WILL ALSO ADJUST TEMPS TO REFLECT THE MOVEMENT OF THE WARM FRONT AND TIMING OF THE COLD FRONT. -SMITH TUESDAY AND TUESDAY NIGHT: EXCEPT FOR THE POSSIBILITY OF SOME LINGERING PRECIP ACROSS THE COASTAL PLAIN THROUGH MID MORNING... EXPECT TUESDAY AND TUESDAY NIGHT TO BE DRY...ALTHOUGH LINGERING LOW CLOUDS ARE EXPECTED. THE COLD FRONT...WHICH ACCORDING TO THE GFS STALLS ACROSS THE AREA DURING THE DAY...SHOULD PROGRESS THROUGH THE REST OF THE AREA TUESDAY NIGHT AS THE LOW PULLS AWAY FROM NEW ENGLAND AND THE TROUGH MOVES OFF THE COAST. THE UPPER LEVEL TROUGH AXIS WILL REMAIN WEST OF CENTRAL NC UNTIL TUESDAY NIGHT. EXPECT HIGH TEMPS TUESDAY TO RANGE FROM THE MID 60S NW TO LOWER 70S SE. LOWS TUESDAY NIGHT WILL BE QUITE A BIT COOLER THAN MONDAY NIGHT...MAINLY IN THE MID TO UPPER 40S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 245 PM MONDAY... A MID-LEVEL TROUGH MOVES THROUGH WEDNESDAY...WITH HEIGHT RISES TAKING PLACE WEDNESDAY NIGHT. A WEAK SURFACE TROUGH IS FORECAST TO MOVE THROUGH CENTRAL NORTH CAROLINA UNDER BROAD SURFACE HIGH PRESSURE...WITH GENERAL SUBSIDENCE ALSO FORECAST OVER THE AREA. A MODEST 850MB THETA-E RIDGE IS IN PLACE OVER CENTRAL NORTH CAROLINA WHILE K INDICES FALL LATE IN THE DAY FROM NEAR 20 TO AROUND ZERO BY NIGHTFALL. JET SUPPORT BY WEDNESDAY IS FORECAST TO BE EAST OF THE AREA WITH ONLY MODEST 850MB LIFT FORECAST BY THE GFS. LIFTED INDICES FALL TO NEAR ZERO IN THE AFTERNOON...AND WHILE MLCAPE IN THE LOWEST KM HARDLY REGISTERS ON THE GFS...1000-500MB LAPSE RATES ARE QUITE STEEP EARLY WEDNESDAY AFTERNOON...AT OR SLIGHTLY GREATER THAN 7.5C/KM. BUFR SOUNDINGS SHOW THE CAP ALOFT IS WEAK...INCREASING AROUND 700MB BY 00Z...BUT FOR THE AFTERNOON UNTIL THEN...IN THE COOL TROUGH ALOFT...AN ISOLATED SHOWER IS POSSIBLE. INCREASING STABILITY WITH AN INCREASING CAP ALOFT DURING WEDNESDAY NIGHT SHOULD KEEP ANY SHOWER DIURNAL IN NATURE. FORTUNATELY...DESPITE THE LOW-LEVEL DRY AIR AND THE STEEP LAPSE RATES...WINDS ALOFT TO 700MB ARE MAINLY AT OR BELOW 25KT...AND MID-LEVEL MOISTURE IS LIMITED IN VOLUME...SO THE POTENTIAL FOR ANY VERY GUSTY WIND WITH A SHOWER IS CURRENTLY LOW. 1000-850MB THICKNESSES FOR WEDNESDAY SUPPORT HIGHS AT LEAST IN THE MID 60S...AND WITH THE COOL TROUGH OVERHEAD WILL LEAN TOWARD THE COOLER MAV GUIDANCE FOR HIGHS ON WEDNESDAY. OVERNIGHT WEDNESDAY NIGHT...GFS BUFR SOUNDINGS SHOW DECOUPLING SHOULD TAKE PLACE...AND THE AIR MASS BECOMES RATHER DRY THROUGH THE COLUMN ESPECIALLY NORTH OF KFAY. UNDER THE SURFACE RIDGE LATE AT NIGHT...GOOD RADIATIONAL COOLING POTENTIAL EXISTS...AND HAVE CONTINUED A TREND COOLER THAN GUIDANCE FOR LOWS...MOSTLY 37 TO 42. IF THIS TREND CONTINUES OR REMAINS EXPECTED...PATCHY FROST WILL BE POSSIBLE PARTICULARLY OVER SOME AREAS ALONG AND NORTH OF ABOUT U.S. 64 AND COULD BE ADDED TO LATER FORECASTS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 245 PM MONDAY... THE LONG-TERM PART OF THE FORECAST WILL FEATURE A SHORTWAVE RIDGE MOVING THROUGH CENTRAL NORTH CAROLINA THURSDAY...FOLLOWED BY INCREASING TROUGHINESS ALOFT FRIDAY AND SATURDAY AS A COLD FRONT MOVES SOUTH TOWARD THE AREA. THE GFS IS WEAKER THAN THE ECMWF WITH THE WAVE ALOFT AND THE FRONT...THOUGH BOTH MODELS...IN ADVANCE OF THE FRONT MOVING INTO CENTRAL NORTH CAROLINA...INCREASE SURFACE RIDGING WEST OVER THE GULF SLIGHTLY SUCH THAT AVAILABLE MOISTURE AND CONVERGENCE MAY DIMINISH AS THE FRONT MOVES SOUTH. REGARDLESS OF THE STRENGTH OF THE UPPER-LEVEL FEATURES...BOTH MODELS SUPPORT WEAKENING OF THE FRONT SO THAT PRECIPITATION CHANCES MAY BE LOW AS THE FRONT MOVES THROUGH. THURSDAY THROUGH FRIDAY DURING THE DAY WILL REMAIN DRY...AND WILL RETAIN THE SMALL CHANCES FOR SHOWERS FOR FRIDAY NIGHT AND INTO SATURDAY FOR NOW AS THE FRONT APPROACHES. BY SATURDAY NIGHT...SUBSIDENCE IN THE WAKE OF WHATEVER IS LEFT OF THE FRONT AND DRIER AIR FORECAST BY THE LONG-TERM GUIDANCE WILL KEEP CHANCES BELOW SLIGHT...CONTINUING THROUGH SUNDAY UNDER SURFACE HIGH PRESSURE. CURRENTLY...AS THE SURFACE HIGH RETREATS MONDAY...AVAILABLE MOISTURE SHOULD INCREASE ALONG WITH THE CHANCES FOR PRECIPITATION. THE ECMWF IS SLOWER THAN THE GFS DUE TO A DEEPER UPPER LOW AS A RESULT OF SOME PHASING OF MODERATE WAVES IN THE NORTHERN AND SOUTHERN STREAMS... WHILE THE GFS IS MORE PROGRESSIVE...INTRODUCING GOOD QPF INTO CENTRAL NORTH CAROLINA DURING THE DAY MONDAY. EVEN THE ECMWF...WITH A FLOW OFF OF THE ATLANTIC...SUGGESTS THE POTENTIAL FOR A SHOWER OR TWO MONDAY...THOUGH WITH BETTER CHANCES HOLDING OFF UNTIL JUST BEYOND THIS LONG-TERM FORECAST PERIOD. THE BEST COURSE OF ACTION CURRENTLY WILL BE TO FOLLOW A CONSENSUS APPROACH WITH SLIGHT CHANCES FOR SHOWERS MONDAY AND GENERAL CHANCES FOR SHOWERS MONDAY NIGHT. DESPITE SYNOPTIC-SCALE DIFFERENCES IN PARTS OF THIS FORECAST PERIOD...THE MOS GUIDANCE FROM BOTH THE MEX AND MEE ARE VERY SIMILAR AND ALSO FAIRLY SIMILAR TO EXPECTATIONS FOR HIGHS BASED UPON 1000- 850MB THICKNESSES. HIGH TEMPERATURES WILL BE FORECAST AROUND 70 THURSDAY AND MOSTLY IN THE MID 70S TO NEAR 80 FOR THE REST OF THIS PART OF THE FORECAST PERIOD. OVERNIGHT LOWS MOSTLY IN THE MID TO UPPER 40S THURSDAY NIGHT...AROUND 50 TO THE MID 50S FRIDAY AND SATURDAY NIGHTS...THEN GRADUALLY WARMING TO LOWS TO AROUND 60 MONDAY NIGHT BASED ON THE CURRENT TIMING OF THE FRONT MOVING THEN TOWARD CENTRAL NORTH CAROLINA. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 150 AM TUESDAY... 24 HOUR TAF PERIOD: A COLD FRONT WILL MOVE ACROSS THE AREA THIS MORNING. AHEAD OF THIS FRONT EXPECT GENERALLY IFR TO MVFR CONDITIONS WILL DEVELOP/CONTINUE... WITH EVEN SOME LIFR CONDITIONS POSSIBLY AT KGSO/KINT. IN ADDITION ISOLATED SHOWERS WILL BE POSSIBLE UNTIL THE FRONT MOVES ACROSS A GIVE LOCATION... ALONG WITH THE THREAT OF A FEW WIND GUSTS OF UP TO 20 KTS TO EVEN 30 KTS IN SHOWERS. EXPECT THE FRONT WILL MOVE THROUGH THE TRIAD REGION IN THE 09-11Z TIME FRAME.... KRDU AROUND 12Z AND KFAY/KRWI 13-16Z. WE MAY SEE SOME OF THE LOWER LEVEL MOISTURE LINGERING AT KFAY AND KRWI AS A LINGERING SURFACE TROUGH IS EXPECTED TO STALL ACROSS OUR FAR EASTERN/SOUTHEASTERN REACHES OF CENTRAL NC. THUS... WILL NOT SHOW CONDITIONS BECOMING VFR AT KFAY AND KRWI UNTIL 18Z... WITH EVEN A SMALL THREAT OF SOME LINGERING SHOWERS TOO. OTHERWISE... EXPECT WINDS WILL SWING AROUND TO MORE OF A WNW TO NW DIRECTION BEHIND THE FRONT... WITH WINDS BECOMING NORTHERLY TONIGHT. OUTLOOK: AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA WEDNESDAY... WITH POSSIBLY SOME VERY LIGHT SHOWERS. HOWEVER... AT THIS TIME EXPECT VFR CONDITIONS ARE EXPECTED ON WEDNESDAY AS MODELS HAVE TREND A BIT DRIER. OTHERWISE... MAINLY VFR CONDITIONS EXPECTED FOR THE REMAINDER OF THE PERIOD. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BSD/KCP NEAR TERM...KCP/SMITH SHORT TERM...DJF LONG TERM...DJF AVIATION...BSD
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1028 AM EDT TUE APR 8 2014 .SYNOPSIS... LOW PRESSURE MOVES THROUGH THE EASTERN GREAT LAKES THIS MORNING AND PASSES NORTH OF NEW ENGLAND THIS AFTERNOON. THIS WILL SWING A COLD FRONT ACROSS THE REGION DURING THE AFTERNOON. HIGH PRESSURE THEN BUILDS FAIR COOLER WEATHER FOR THE MIDWEEK. A COLD FRONT WITH LOW PRESSURE MOVING ALONG IT MAY BRING SHOWERS LATE FRI INTO SAT. DRY AND WARM WEATHER IS EXPECTED SUNDAY AND DURING THE DAY ON MON. A FEW SHOWERS COULD REACH WESTERN AREAS LATE MON AHEAD OF A COLD FRONT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1015 AM UPDATE... BACK EDGE OF THE SHOWERS ASSOCD WITH DEPARTING SW LLJ IS EXITING EASTERN MA...BUT SHOWERS LIFTING NE FROM S OF NEW ENG WILL AFFECT THE CAPE/ISLANDS THROUGH MIDDAY AND POSSIBLY INTO EARLY AFTERNOON ACROSS ACK PER HRRR SOLUTION. AREAS OF DENSE FOG HAVE DEVELOPED ALONG THE SOUTH COAST AS HIGHER DEWPOINT AIR ADVECTS OVER THE COLD WATERS AND WARM FRONT LIFTS N ACROSS SNE. THE FOG WILL LIKELY LINGER INTO THE AFTERNOON BEFORE GRADUALLY LIFTING AS LOW LEVEL WINDS VEER AND INCREASE. EXPECT PARTIAL CLEARING DEVELOPING IN THE INTERIOR DURING THE AFTERNOON AS THE LOW LEVELS DRY OUT...BUT LOW CLOUDS WILL PERSIST IN SE COASTAL NEW ENG FOR MUCH OF THE DAY. AS MID LEVEL TROF LIFTS TO THE NORTH THIS AFTERNOON...COULD SEE AN ISOLD SHOWER DEVELOP ACROSS NW ZONES. 925 MB TEMPS 10-11C WOULD SUPPORT TEMPS NEAR 70 AWAY FROM THE COAST WITH FULL SUNSHINE. BUT CLOUD COVER WILL KEEP IT COOLER SO EXPECT MAX TEMPS LOW TO MID 60S...EXCEPT MID/UPPER 50S IMMEDIATE S COAST AND CAPE/ISLANDS. GUSTY SW WINDS DEVELOPING THIS AFTERNOON...ESPECIALLY INTERIOR AS MIXING DEPTH INCREASES. SOUNDINGS SUPPORT WIND GUSTS TO 30 KT. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... UPPER TROUGH APPROACHES TONIGHT AND MOVES ACROSS NEW ENGLAND WEDNESDAY. SURFACE HIGH PRESSURE BUILDS OVER THE REGION. SOME SKY COVER MAY LINGER FOR PART OF TONIGHT BUT OTHERWISE THE AIRMASS WILL SHOW A DRYING TREND. MIXING ON WEDNESDAY SHOULD REACH 850 MB. WINDS IN THE MIXED LAYER REACH 25 KNOTS...SO WIND GUSTS OF 25-30 MPH ARE POSSIBLE. TEMPS AT 850 MB WILL BE -2C TO -5C...SO MAX TEMPS SHOULD BE IN THE UPPER 40S TO MID 50S. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... HIGHLIGHTS... * COLD FRONTAL PASSAGE ON FRIDAY * QUICK MOVING COASTAL LOW PRESSURE SYSTEM ON SATURDAY * ABOVE AVERAGE TEMPERATURES ARE EXPECTED ON SUNDAY/MONDAY MODELS AND CONFIDENCE... OVERALL HAVE MODERATE CONFIDENCE IN THE FORECAST. BELIEVE THAT PRECIP WILL OCCUR BUT THE TIMING AND LOCATION OF HEAVIER RAINFALL FOR THE WEEKEND ARE STILL UNCERTAIN. INCREASING CONFIDENCE THAT TEMPS WILL BE WARMING AT OR ABOVE AVERAGE FOR THE REST OF THE WEEKEND AND INTO THE WEEKEND. A LOT OF UNCERTAINTY LEADING UP TO NEXT WEEK AS STRONG TROUGH DIGS TOWARDS THE NORTHEAST. OVERALL 00Z MODEL GUIDANCE IS IN GOOD AGREEMENT. LONG WAVE TROUGH WILL SET UP OVER THE GREAT LAKES AND INTO THE NORTHEAST STARTING ON THURSDAY LASTING TO SUNDAY. A FEW RIPPLES IN THE FLOW WILL RESULT IN SOME PRECIP ON FRIDAY AND SATURDAY...BUT DEF NOT A WASHOUT. HIGH PRESSURE WILL SET UP LATE SATURDAY WITH A WARM FRONT TO FOLLOW ON SUNDAY. GUIDANCE IS SHOWING A STRONG COLD FRONT MOVING THROUGH THE REGION...AROUND TUESDAY. OVERALL TREND IN THE FORECAST WAS TO LEAN TOWARDS THE EC ENSEMBLES WHICH IS IN THE MIDDLE OF THE ROAD COMPARED TO THE PROGRESSIVE GFS AND MORE AMPLIFIED DETERMINISTIC EC. DETAILS... WEDNESDAY NIGHT INTO THURSDAY... HIGH PRESSURE WILL BUILD ACROSS THE MID-ATLANTIC RESULTING IN CLEAR SKIES AND DRY WEATHER FOR THE REGION. TEMPERATURES OVERNIGHT WILL BE CHILLY AS TEMPS WILL RADIATE OUT INTO THE UPPER 20S TO LOW 30S. HOWEVER RETURN FLOW WILL OCCUR ACROSS THE REGION ON THURSDAY RESULTING IN A WARM-UP INTO THE LOW TO MID 60S. TEMPERATURES WILL BE COOLER ALONG THE COASTLINE AS SEA-BREEZES SET-UP. WINDS BY THE LATE AFTERNOON INTO THE OVERNIGHT HOURS ON THURSDAY WILL STRENGTHEN AS LLJ INCREASES ACROSS SOUTHERN NEW ENGLAND. EXPECT GUSTS BETWEEN 25 TO 30 MPH. WHILE THIS OCCURS...RH VALUES WILL DROP INTO THE MID TO LOW 20S WHICH COULD RESULT IN POSSIBLE FIRE HEADLINES ON THURSDAY. FRIDAY INTO SATURDAY.... COLD FRONT WILL MOVE ACROSS THE REGION ON FRIDAY SPOUTING OFF A FEW SCATTERED SHOWERS FRIDAY MORNING INTO THE AFTERNOON. PRECIP SHOULD COME TO AN END BY THE EVENING HOURS. HOWEVER A QUICK MOVING OPEN WAVE WILL STRENGTHEN RESULTING IN THE DEVELOP OF A CLOSED LOW AT 850MB ALONG THE FRONT. THIS LOW WILL RIDE ALONG THE FRONT LATE FRIDAY NIGHT INTO SATURDAY SPOUTING OFF MORE SHOWERS. SHOWALTERS WILL DROP BELOW 0 OVER THE SOUTHERN WATERS BUT HELD OFF ON INSERTING THUNDER INTO THE GRIDS AT THIS TIME BECAUSE OF SOME UNCERTAINTY. BOTH THE EC AND GFS SHOW DIFFERENCES IN TERMS OF QPF AMOUNT WITH THE GFS SHOWING OVER AN INCH WITH THE EC CLOSER TO A HALF OF AN INCH. TRENDED TOWARDS THE MIDDLE WITH QPF AMOUNTS NEAR 0.75 INCHES. UNCERTAIN ON HOW THIS MAY IMPACT THE ALREADY SWOLLEN RIVERS BUT CANNOT RULE OUT THE POTENTIAL FOR POOR DRAINAGE FLOODING AS WELL AS SMALL STREAM FLOODING. TEMPERATURES ON BOTH DAYS WILL BE IN LOW TO MID 60S. SUNDAY INTO MONDAY... HIGH PRESSURE WILL BUILD ACROSS LONG ISLAND ON SUNDAY MORNING. A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE NORTHERN GREAT LAKES PUSHING THE WARM FRONT INTO NORTHERN NEW ENGLAND. A FEW SHOWERS MAY DEVELOP ESP ACROSS THE WEST BUT LEFT THEM OUT OF THE FORECAST FOR NOW AS CONFIDENCE IS LOW. ENFORCING WARM FRONT WILL PASS OVER THE REGION ON MONDAY WITH BOTH DAYS WARMING INTO THE UPPER 60S TO PERHAPS THE 70S BY MONDAY. 850MB TEMPS ON MONDAY WILL WARM UP TO 12C AND WITH ABUNDANT SUNSHINE HAVE KEPT PREV FORECASTERS LOW 70S INTO THE FORECAST...WHICH IS STILL SEVERAL DEGREES ABOVE AVERAGE. ALL OF THIS IS DUE TO AN 850MB DIGGING TROUGH LOCATED ACROSS THE MIDWEST WHICH WILL RESULT IN SIGNIFICANT RIDGING OVER THE NORTHEAST. TUESDAY AND BEYOND.... LARGEST UNCERTAINTY IN THE FORECAST AS THERE IS SIGNIFICANT TIMING DIFFERENCES. REGARDLESS MODELS AND THEIR ENSEMBLES ARE SHOWING A DIGGING TROUGH MOVING INTO NEW ENGLAND WITH A STRONG COLD FRONT ASSOCIATED WITH IT. TEMPERATURES BEHIND THE FRONT MAY BE 20 DEGREES COOLER THEN TEMPS ON SUNDAY/MONDAY. THIS SHOWS THAT THERE IS SIGNIFICANT DYNAMICS AT PLAY...WHICH MAY RESULT IN POSSIBLE THUNDER ALONG THE FRONT. IF TEMPERATURES DROP AS LOW AS THE EC SUGGEST THEN THERE IS A POSSIBILITY OF THE RETURN TO A WINTRY MIX NORTH OF ROUTE 2. THERE IS STILL A LOT OF UNCERTAINTY SO STAY TUNED TO THE LATEST FORECASTS. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH WEDNESDAY/...MODERATE CONFIDENCE. LIFR IN DENSE FOG WILL LINGER INTO THE EARLY AFTERNOON NEAR THE SOUTH COAST BEFORE SLOWLY LIFTING...BUT AREAS OF IFR CIGS WILL LIKELY PERSIST THROUGH THE DAY NEAR THE COAST. ELSEWHERE...IFR WILL GRADUALLY IMPROVE TO MVFR/VFR CIGS FROM WEST TO EAST THIS AFTERNOON. SW WIND GUSTS TO 30 KTS DEVELOPING. TONIGHT... VFR...EXCEPT LINGERING MVFR/IFR OUTER CAPE/ACK IN THE EVENING. WEDNESDAY... VFR. NORTHWEST WIND GUSTS TO 25 KNOTS. KBOS TERMINAL...MODERATE CONFIDENCE IN TAF. KBDL TERMINAL...MODERATE CONFIDENCE IN TAF. OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY... WEDNESDAY NIGHT INTO THURSDAY...HIGH CONFIDENCE VFR. FRIDAY...MODERATE CONFIDENCE. WINDS SHIFT TO THE SW WITH POTENTIAL FOR GUSTS TO 20-25 KT AT TIMES. MAINLY VFR...BUT SOME MVFR POSSIBLE IN SCATTERED SHOWERS ALONG A COLD FRONT. FRIDAY NIGHT AND SATURDAY...MODERATE CONFIDENCE. MVFR CEILINGS AND VSBYS IN SHOWERS...ESPECIALLY IN CT/RI/SOUTHEAST MA. LOCAL IFR POSSIBLE FRIDAY NIGHT. CONDITIONS IMPROVING TO VFR SATURDAY AFTERNOON. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM /THROUGH WEDNESDAY/...MODERATE CONFIDENCE. TODAY... OBSERVATIONS SHOW WIND GUSTS 23-33 KNOTS WITH A GUST TO 36 KNOTS AT BUZZARDS BAY...ALTHOUGH ELEVATION MAY BE CONTRIBUTING TO THE BUZZARDS GUST. WINDS AT 2000 FEET ABOVE THE OCEAN SURFACE ARE 35-40 KNOTS NEAR BOSTON AND PROVIDENCE...AND 50-60 KNOTS OVER THE CAPE AND ISLANDS. MUCH OF THIS WILL STAY ALOFT...BUT SOME OF THIS WIND MAY BE BROUGHT TO THE SURFACE IN GUSTS...ESTIMATE CONTINUES TO BE AROUND 30 KNOTS. THIS LINES UP WELL WITH OBSERVATIONS...SO WE WILL CONTINUE THE SMALL CRAFT ADVISORY FOR ALL WATERS TODAY. THE STRONG WINDS ALOFT WILL MOVE OFF BY THIS AFTERNOON. TONIGHT... SOUTHWEST WINDS WILL SHIFT TO WEST AND DIMINISH BELOW 25 KNOTS. HOWEVER A 5-8 FOOT SWELL WILL LINGER ON THE OUTER WATERS AND THE RI WATERS. SMALL CRAFT HEADLINES CONTINUE EARLY NIGHT ON ALL WATERS EXCEPT BOSTON HARBOR AND NARRAGANSETT BAY. HEADLINES SHOULD DROP ON THE MASSACHUSETTS NEARSHORE WATERS OVERNIGHT. WEDNESDAY... WINDS SHIFT TO NORTHWEST WITH GUSTS TO 20 KNOTS WHILE SEAS CONTINUE TO FEATURE 5-8 FOOT SWELL ON THE EXPOSED WATERS. EXPECT TO CONTINUE SMALL CRAFT HEADLINES IN THOSE AREAS. OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY... WEDNESDAY NIGHT...HIGH CONFIDENCE. BOTH WINDS AND SEAS WILL BEGIN TO RELAX SUCH THAT SOME SMALL CRAFT ADVISORIES WILL LIKELY BE ABLE TO BE DROPPED. THURSDAY...HIGH CONFIDENCE. BRIEF PERIOD OF QUIET BOATING WEATHER AS WINDS SHIFT TOWARD THE SW. BUT THEN WINDS AND SEAS INCREASE AGAIN TOWARD THU EVENING WITH GUSTS TO 30 KT POSSIBLE OVER THE EASTERN MA OUTER WATERS. SCA WILL BE NEEDED. FRIDAY AND SATURDAY...MODERATE CONFIDENCE. SOUTHWESTERLY FLOW WITH SEAS INCREASING OVER THE OUTER WATERS SOUTH OF NEW ENGLAND AND EAST OF CAPE COD. WINDS COULD STILL GUST TO 20-30 KT AT TIMES...ESPECIALLY THU NIGHT/FRIDAY MORNING AS A COLD FRONT PASSES THROUGH. A COASTAL LOW WILL DEVELOP LATE FRIDAY INTO SATURDAY CLOSE TO THE SOUTH SHORE...WHICH WILL QUICKLY MOVE THE WESTERLY WINDS OUT OF THE NORTHEAST. && .HYDROLOGY... SHOWERS WILL CONTINUE THROUGH THE MORNING...THEN DIMINISH IN COVERAGE AS THE STRONGEST LIFT SHIFTS NORTH. A COLD FRONT COULD THEN BRING SHOWERS MIDDAY/EARLY AFTERNOON. SIX-HOUR RAINFALL RATES HAVE BEEN LESS THAN 0.25 INCH...SO MOST RAINFALL TOTALS SHOULD BE BELOW 1 INCH. THERE REMAINS A CONCERN FOR AREAS OF URBAN AND POOR DRAINAGE FLOODING...BUT EVEN THIS RISK IS DIMINISHING. RIVERS SHOULD REMAIN WITHIN THEIR BANKS. THE THREAT OF RIVER FLOODING WOULD INCREASE SIGNIFICANTLY IF RAINFALL EXCEEDS 2 INCHES. CHECK THE LATEST FLOOD FORECAST STATEMENTS OR PLEASE GO TO THE WEB PAGE HTTP:/WATER.WEATHER.GOV/AHPS2/INDEX/PHP?WFO=BOX...THIS WILL DISPLAY STATUS OF OBSERVATIONS. FOR THE MAP WITH MAX FORECAST CREST CLICK ON THE RIVER FORECASTS TAB. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT WEDNESDAY FOR ANZ231>234- 251. SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ230- 236. SMALL CRAFT ADVISORY UNTIL 6 PM EDT WEDNESDAY FOR ANZ235-237- 250-254>256. && $$ SYNOPSIS...WTB/DUNTEN NEAR TERM...WTB/KJC SHORT TERM...WTB LONG TERM...DUNTEN AVIATION...KJC/WTB/DUNTEN MARINE...WTB/DUNTEN HYDROLOGY...
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
921 AM CDT TUE APR 8 2014 .DISCUSSION... 301 AM CDT PRECIP CHANCES TODAY AND TIMING OF A COOL FRONT THURSDAY AND ASSOCIATED AFFECT ON TEMPERATURES ARE SOME OF THE CONCERNS THIS FORECAST PERIOD. EARLY MORNING WATER VAPOR IMAGERY SHOWS THE HIGH AMPLITUDE UPPER FLOW CONTINUING TO BE IN PLACE WITH A LARGE LONGWAVE TROUGH SHIFTING EAST ACROSS THE MID SECTION OF THE COUNTRY WHILE A LARGE RIDGE MOVES EAST INTO THE ROCKIES. BETWEEN THESE TWO FEATURES IS A VORT MAX THAT IS SWINGING ACROSS THE LOCAL AREA THIS MORNING BRINGING BANDS OF LIGHT RAIN WITH IT. IN ADDITION...A NARROW SHEARED TROUGH AXIS IS MOVING SOUTHEAST INTO WESTERN MINNESOTA/IOWA/MISSOURI WHICH WILL CROSS THE AREA LATER TODAY AIDING IN ADDITIONAL SHOWER CHANCES. FURTHER WEST...A CLOSED UPPER LOW IS SPINNING OFF THE CENTRAL BRITISH COLUMBIA COAST WITH A WAVE LIFTING NORTHEAST OVER THE SOUTHERN B.C COAST AHEAD OF IT. THIS ENERGY WILL DRIVE SURFACE LOW PRESSURE DEVELOPMENT ACROSS WESTERN CANADA WHICH WILL BRING THE AFOREMENTIONED COLD FRONT THURSDAY. AT THE SURFACE...LOW PRESSURE IS MOVING NORTHEAST TOWARD WESTERN NEW YORK WITH HIGH PRESSURE OVER NORTHERN MANITOBA. PRESSURE FALLS ARE BUILDING ACROSS WESTERN CANADA AS THE UPPER WAVES APPROACH. TODAY AND TONIGHT...A MIX OF CLOUDS AND SUN ARE EXPECTED TODAY THANKS TO A COMBINATION OF LAGER SCALE ASCENT PROVIDED BY THE LARGE SCALE TROUGH...STEEP LOW LEVEL LAPSE RATES WITH SOME COOLING ALOFT...AND SOME SLIGHTLY BETTER FOCUSED LIFT WITH THE SHEARED TROUGH AXIS THAT WILL CROSS LATER TODAY. THE BANDS OF LIGHT RAIN CURRENTLY ACROSS THE EASTERN THIRD TO HALF OF THE AREA WILL CONTINUE TO MOVE SOUTHEAST AND LIKELY BE CONFINED TO LAKE MICHIGAN AND NW INDIANA IN THE 12-15Z TIME FRAME BEFORE FADING OR EXITING TO THE EAST. OTHERWISE PRECIP DEVELOPMENT LOOKS TO BE MORE DIURNALLY DRIVEN AS SURFACE TEMPS WARM UP AND LAPSE RATES STEEPEN. THE NEXT FOCUSED TROUGH AXIS ARRIVES THIS AFTERNOON BUT THERE MAY BE SOME WEAKER VORT MAXIMA THAT PASS AHEAD OF IT WHICH COULD DRIVE SOME SPOTTY PRECIP ACTIVITY THROUGH THE MORNING WEST OF THE CURRENT ACTIVITY. OTHERWISE THE BEST TIME LOOKS TO BE THIS AFTERNOON AND EARLY THIS EVENING AS THE TROUGH AXIS PASSES. NORTHERLY WINDS WILL BE IN PLACE AND THE FLOW WILL BE WEAK ENOUGH TO TRIGGER A LAKE BREEZE. GIVEN THE STEEP LOW LEVEL LAPSE RATES THE LAKE BREEZE MAY PROVIDE ENOUGH LOW LEVEL CONVERGENCE TO TRIGGER SHOWERS AS WELL. WILL CONTINUE WITH MENTIONABLE POPS FOR THE ENTIRE AREA WITH THE GREATEST FOCUS ACROSS THE EASTERN HALF OR SO WHERE THE BEST COMBINATION OF UPPER TROUGH TIMING/LAPSE RATES/LAKE BREEZE COME TOGETHER. THIS INCLUDES MUCH OF THE CHICAGO METRO SOUTH TO THE KANKAKEE...PONTIAC...GIBSON CITY AREA. HIGHS WILL BE TRICKY GIVEN THE EXPECTED MIX OF SUN AND CLOUDS BUT SOME CLEARING MAY OCCUR EARLY IN THE WEST...BEFORE DIURNAL CU INCREASES...TO ALLOW TEMPS TO JUMP A BIT SO THE FORECAST COULD BE A LITTLE ON THE COOL SIDE BUT OVERALL EXPECT MID 50S WEST AND AROUND 50 EAST...WITH LOW TO MID 40S WITHIN A FEW MILES OF LAKE MICHIGAN. SOME OF THESE AREAS WITHIN 5-10 MILES OF THE LAKE MAY SEE AN EARLY HIGH THEN FALL DURING THE AFTERNOON AS THE BOUNDARY PASSES...WITH ANY SHOWER ACTIVITY ALSO AFFECTING HOURLY TEMP TRENDS. THE TROUGH AXIS WILL EXIT TO THE EAST EARLY THIS EVENING BUT SOME SHOWER ACTIVITY MAY LINGER JUST BEYOND SUNSET IN THE EAST BEFORE ENDING. HIGH PRESSURE WILL CROSS THE AREA OVERNIGHT ALLOWING FOR LIGHT WINDS AND COOLING TO AROUND 30 DEGREES FOR MOST AREAS TONIGHT. WEDNESDAY AND THURSDAY...THE UPPER FLOW WILL GO THROUGH A TRANSITION WEDNESDAY AND THURSDAY AS THE WESTERN RIDGE MOVES EAST AND DE-AMPLIFIES THANKS TO THE TROUGH OFF THE B.C. COAST MOVING INLAND AND FLATTENING IT. MID LEVEL WARMING WILL INCREASE WEDNESDAY AS H85 TEMPS JUMP TO AROUND +8C BY EVENING AND +12 TO +14C BY THURSDAY. SURFACE LOW PRESSURE WILL MOVE ACROSS SOUTHERN CANADA WITH A COLD FRONT TRAILING IT TO THE SOUTHWEST. THE PRESSURE GRADIENT BETWEEN THIS SYSTEM AND THE HIGH DEPARTING TO THE EAST WILL SUPPORT AN INCREASING SOUTHWEST WIND...WHICH WILL BECOME GUSTY WEDNESDAY NIGHT AND THURSDAY. ALL OF THIS POINTS TO A WARM UP INTO THE UPPER 50S EAST TO LOWER 60S WEST WEDNESDAY WITH THE FLOW STRONG ENOUGH TO PRECLUDE LAKE BREEZE DEVELOPMENT. TEMPS THURSDAY BECOME A BIT TOUGHER THANKS TO THE COLD FRONT CROSSING THE AREA DURING THE DAY. LATEST TRENDS BRING THE FRONT THROUGH A LITTLER SOONER...AROUND MIDDAY. THIS WILL LIMIT THE WARMING POTENTIAL FOR MUCH OF THE AREA COMPARED TO WHAT WAS SUGGESTED TO BE POSSIBLE WITH EARLIER FORECASTS. TIMING STILL SUBJECT TO CHANGE BUT WILL GO WITH HIGHS IN THE LOWER 60S NORTH TO THE UPPER 60S SOUTH. FAR SOUTHERN AREAS COULD STILL SEE 70 IF CLOUDS CAN BE THIN ENOUGH AND SOME COMPRESSIONAL WARMING CAN DEVELOP AHEAD OF THE FRONT. THE FRONT WILL BRING SOME CHANCE FOR RAIN WITH IT BUT THE BEST FORCING WILL BE FURTHER NORTH IN BETTER PROXIMITY TO UPPER FORCING. FRIDAY THROUGH THE WEEKEND...WITH THE REDUCED AMPLITUDE OF THE UPPER FLOW THE PUSH OF COOLER AIR BEHIND THE FRONT WILL NOT BE ALL THAT STRONG. THERE ARE SIGNS OF A WEAK TROUGH CROSSING THE AREA FRIDAY WHICH COULD PROVIDE SOME CLOUD COVER BUT THERE SHOULD BE ENOUGH SUN TO PUSH TEMPS INTO THE LOW TO MID 60S. HIGH PRESSURE WILL QUICKLY CROSS THE AREA SO THE FLOW MAY BE WEAK ENOUGH TO SUPPORT A LAKE BREEZE SO LAKESHORE AREAS MAY BE HELD TO THE 40S ONCE AGAIN. MEDIUM RANGE GUIDANCE CONTINUES TO SHOW SPLIT FLOW TROUGHING WORKING INTO THE WESTERN U.S. INTO SATURDAY DRIVING SURFACE LOW PRESSURE DEVELOPMENT ACROSS THE CENTRAL/NORTHERN PLAINS. THIS WILL SUPPORT A STRONGER SOUTHERLY FLOW FOR SATURDAY AND ANOTHER SURGE IN TEMPS WHICH LOOK TO BE IN THE MID AND UPPER 60S AT THIS POINT. SATURDAY LOOKS DRY AT THIS TIME BUT THE SYSTEM TO THE WEST WILL MOVE IN BRINGING RAIN CHANCES SATURDAY NIGHT. CONFIDENCE LOWERS FOR THE REST OF THE WEEKEND INTO MONDAY AS THE EVOLUTION OF THE NORTHERN AND SOUTHERN STREAM TROUGHS WILL DICTATE HOW PROGRESSIVE THE SYSTEM IS IN CROSSING THE AREA. REGARDLESS...A PERIOD OF RAIN LOOKS MORE LIKELY FROM AS EARLY AS SATURDAY NIGHT THROUGH SUNDAY AND POSSIBLY LONGER WITH THE SPEED OF DEPARTURE BEING MUCH LESS CERTAIN. A GOOD SIGNAL FOR MUCH COOLER AIR EARLY NEXT WEEK CONTINUES WHICH MAY MEAN SOME MIXED PRECIP/SNOW AS PRECIP ENDS. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * NORTHWEST WINDS ARND 10 KT BECOME NE 8-10 KT THIS AFTN. * SCT -SHRA EXPECTED ALONG THE LAKE BREEZE BOUNDARY. * LOW END VFR/HIGH END MVFR CIGS PSBL THIS AFTN ASSOCIATED WITH THE -SHRA. BEACHLER //DISCUSSION...UPDATED 14Z... SPRINKLES AND SPOTTY SHOWERS HAVE PUSHED EAST OF THE TAF SITES AND STEADILY DISSIPATING. WINDS HAVE BEGUN TO TURN NORTHWESTERLY AND WILL EVENTUALLY FLIP TO NORTHEAST AT ORD/MDW WITH A LAKE BOUNDARY PUSHING INLAND. THIS WILL ADD TO THE CONVERGENCE AND LIKELY HELP TO REDEVELOP SPOTTY SHOWERS EARLY THIS AFT. IN ADDITION SOME INSTABILITY DOES DEVELOP WITH THE CONVERGENCE OF THE LAKE BOUNDARY...WHICH COULD INITIATE AN ISOLATED THUNDERSTORM. THIS IS A VERY LOW PROBABILITY AND HAVE HELD THIS OUT OF THE TAF. PREVIOUS DISCUSSION UPDATED 12Z... THE BAND OF SHOWERS IS SLOWLY SHIFTING EAST WITH VFR CONDITIONS AND NW WINDS EXPECTED BEHIND IT. THE GRADIENT HAS BEEN TIGHTENING OVER THE PAST COUPLE OF HOURS WITH NW WINDS AT 6-9 KT. WINDS WILL CONTINUE TO INCREASE THROUGH THE MORNING BEFORE A LAKE BREEZE FORMS EARLY THIS AFTN. GUIDANCE CONTINUES TO INDICATE THERE WILL BE A SHARP BOUNDARY JUST WEST OF ORD WHERE WINDS WILL BE NE ARND 10 KT EAST OF THE BOUNDARY AND NNW WEST OF THE BOUNDARY. EXPECTING A DECENT AMOUNT OF CONVERGENCE AND SHOWERS TO BLOSSOM ALONG THE BOUNDARY. COULD SEE LOW END VFR/HIGH END MVFR CIGS WITH THE -SHRA. A RIDGE OF HIGH PRESSURE PUSHES IN FROM THE WEST THIS EVENING AND WINDS TURN BACK TO THE NW ARND 5 KT. DRIER AIR WILL ALSO MOVE IN WITH ONLY HIGH LEVEL CIRRUS EXPECTED. WINDS WILL BACK OVERNIGHT AS THE RIDGE SHIFTS EAST...AND WINDS WILL BE SW ARND 10 KT WEDNESDAY MORNING. JEE //ORD AND MDW CONFIDENCE...UPDATED 14Z... * MEDIUM-HIGH CONFIDENCE IN -SHRA THIS AFTN...AND HIGH CONFIDENCE THAT LOW END VFR/HIGH END MVFR CIGS WILL BE TIED TO -SHRA. * HIGH CONFIDENCE IN WINDS SHIFTING FROM NW TO NE THIS AFTN...MEDIUM CONFIDENCE IN TIMING. * HIGH CONFIDENCE IN ALL OTHER FORECAST ELEMENTS. JEE/BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...VFR. THURSDAY...CHANCE OF RAIN DURING THE DAY. BRIEF MVFR PSBL. FRIDAY...VFR. SATURDAY...CHANCE OF RAIN...VFR. SUNDAY...RAIN LIKELY WITH A CHANCE OF THUNDERSTORMS DURING THE DAY. MVFR PSBL. MONDAY...CHANCE OF RAIN. MVFR PSBL EARLY. JEE && .MARINE... 223 AM CDT LOW PRESSURE IS OVER LAKE ERIE AND IT WILL CONTINUE OFF TO THE NORTHEAST TODAY. NORTH TO NORTHWEST WINDS ARE EXPECTED THROUGH THIS EVENING. WINDS BECOME SOUTHWEST OVERNIGHT AS HIGH PRESSURE PASSES OVERHEAD AND THEN CONTINUES EASTWARD. THE NEXT LOW PASSES OVER NORTHERN ONTARIO WEDNESDAY NIGHT THROUGH THURSDAY WITH ITS COLD FRONT SWINGING THROUGH THURSDAY. SOUTH WINDS WILL INCREASE TO 30 KT AHEAD OF THE LOW WEDNESDAY...AND STILL THINKING IT WILL BE TOO STABLE FOR GALE FORCE GUSTS TO MIX DOWN TO THE SURFACE. WINDS DIMINISH TO 10 TO 20 KT AND BECOME WEST BEHIND THE COLD FRONT THURSDAY. A BROAD AREA OF HIGH PRESSURE BUILDS OVER THE LAKE LATE THIS WEEK WITH LIGHT WEST WINDS EXPECTED THROUGH FRIDAY NIGHT. THE HIGH SHIFTS EAST AND WINDS TURN SOUTH. THE GRADIENT TIGHTENS SATURDAY AHEAD OF THE NEXT LOW WITH GUSTS OF 20-25 KT EXPECTED. GUIDANCE DIFFERS WITH HOW FAST THE LOW MOVES THROUGH THIS WEEKEND SO HAVE MEDIUM CONFIDENCE IN TIMING RIGHT NOW. GUIDANCE DOES AGREE THAT WINDS TURN NORTH BEHIND THE LOW GUSTS TO AT LEAST 30 KT ARE EXPECTED LATE THIS WEEKEND INTO EARLY NEXT WEEK. SOME MODELS SHOW A BRIEF PERIOD OF LOW END GALES...CAPPED WINDS AT 30 KT FOR NOW. HEADLINES...HIGH WINDS MAY LEAD TO SMALL CRAFT CONDITIONS WEDNESDAY NIGHT THROUGH THURSDAY. THEN HIGH WINDS AND WAVES ARE POSSIBLE AGAIN LATE THIS WEEKEND INTO EARLY NEXT WEEK. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion National Weather Service Lincoln IL 900 AM CDT Tue Apr 8 2014 .DISCUSSION... ISSUED 900 AM CDT Tue Apr 8 2014 Mostly sunny skies currently prevail across central Illinois: however, with steep low-level lapse rates noted on 12z KILX and KDVN upper air soundings, think diurnal clouds will quickly develop later this morning into the afternoon hours. Region remains under the influence of a high-amplitude trough that has dug all the way to the Gulf Coast. Several weaker short-waves are noted within the flow, including one feature currently over southwest Iowa into eastern Kansas. This particular wave will drop southeastward and remain largely to the W/SW of Illinois today. Meanwhile, another subtle wave will drop southeastward out of Wisconsin and northeast Iowa. This feature will provide enough lift to trigger a few showers and thunderstorms across the area this afternoon. Latest HRRR seems to have a reasonable handle on the current situation, and depicts isolated to scattered convection developing by around 17/18z. Much of the convection will be focused across the E/NE KILX CWA in association with the advancing Wisconsin wave. Have updated the forecast to remove POPs and reduce sky cover this morning, then have gone with partly sunny conditions with isolated to scattered showers/thunder this afternoon. Temp forecast looks to be on track, so made no adjustments to afternoon highs in the middle to upper 50s. Zone update has already been issued. Barnes && .AVIATION... ISSUED 648 AM CDT Tue Apr 8 2014 A weak surface trough extending along I-70 and dropping southeast will continue out of IL this morning. Aloft, a trailing shortwave will rotate southeast across IL this afternoon triggering scattered showers. Instability parameters show support for some isolated thunderstorms, mainly due to steep lapse rates in the low to mid levels. The better chances will be across eastern IL, so a VCSH was only included this afternoon in the TAFs for the eastern terminals of BMI/DEC/CMI. Diurnal stabilization of the lower troposphere will help to diminish coverage of showers and any storms by sunset. Dry and clear conditions should prevail overnight. Lifted condensation levels look to remain in the VFR category, with ceilings as low as 3.5K feet this afternoon but not too much lower than that. Winds will increase from the NW this morning, with gusts as high as 20kt from late morning through mid afternoon. Wind direction will remain NW tonight as speeds dip below 10kt. Shimon && .PREV DISCUSSION... ISSUED 304 AM CDT Tue Apr 8 2014 Low pressure exiting to the east as more northwesterly flow moves in over the Midwest this morning. Some remnant clouds and weak echoes over the forecast area on radar imagery this morning. Weak wave in the large scale trof bringing in another chance of precip. Some cold air aloft will help to add to some instability this afternoon and cannot rule out some isolated thunder chances. This is the first issue for the forecast. Warming through the week and another weak boundary and system at the end of the weekend. Not too many changes in the latter two systems. Models in good agreement through Friday...with some divergence in handling the Saturday night/Sunday storm. SHORT TERM...Today and tomorrow... Another chance for rain as a secondary wave moves into the larger scale trof aloft...with highs in the 50s. This afternoon will actually see some colder temps aloft and rather steep lapse rates in the low levels. Though the instability is weak...narrow and skinny CAPE in the forecast soundings...it is pretty deep. Cannot rule out some thunder and small hail with a relatively low freezing level. Will see the showers coming to an end this evening. Tomorrow starts a general warming trend with a southerly component working into the winds. Highs in the 60s. LONG TERM...Thursday through Monday... Forecast continues the warming trend resulting in the warmest day of the forecast on Thursday with highs approaching 70/the lower 70s. A system passing across the southern tier of Canada drags a weak frontal boundary across the Great Lakes and the Midwest...but convergence along the boundary is weak at best. Not to mention that the flow across the country is predominantly SW/NE oriented...effectively cutting off the access to deeper Gulf moisture ahead of the boundary. At this point, pops for Thursday night remain on the low side through Friday night. Far more dynamic system expected into the weekend with pops stretching from Sat night through Sunday for now as the quicker GFS/slower ECMWF having major timing differences. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
947 AM EDT TUE APR 8 2014 .UPDATE... ISSUED AT 947 AM EDT TUE APR 8 2014 UPDATED THIS MORNING TO ALLOW FOR A PERIOD OF PARTLY CLOUDY SKIES THROUGH THE MORNING AND AFTERNOON HOURS AS SUBSIDENCE AHEAD OF AN APPROACHING TROUGH ALLOWS FOR SEVERAL BREAKS IN THE CLOUD COVER. THIS MID LEVEL TROUGH WILL PUSH SOUTHEAST ACROSS CENTRAL KENTUCKY THIS EVENING...AND INTO SOUTHEAST KENTUCKY TONIGHT. LATEST HRRR AND RAP CONTINUE TO SHOW PLENTY OF SCATTERED RAIN SHOWER ACTIVITY AS IT PUSHES INTO THE AREA. BEST CONCENTRATION OF SHOWER ACTIVITY LOOKS TO OCCUR SOUTH OF A LINE FROM MOUNT STERLING...TO PIKEVILLE. AS THE WAVE EXITS SOUTHEAST TONIGHT...UPSLOPE FLOW AND SOME LINGERING MOISTURE MAY LEAD TO A PERIOD OF LIGHT RAIN ACROSS THE HIGHER TERRAIN AREAS. AS FOR THUNDER...TIMING IS NOT GREAT AS PRECIPITATION MAY NOT ARRIVE UNTIL NEAR OR AFTER SUNSET WITH INSTABILITY ALREADY STARTING TO DECREASE BY THIS TIME. ON TOP OF THIS...SHEAR REMAINS MINIMAL THIS EVENING...WHICH WILL LIMIT ANY SUSTAINED UPDRAFTS AND THEREFORE LIMITING THE THUNDER POTENTIAL. OVERALL RAIN SHOWER COVERAGE COULD BE ENOUGH TO JUSTIFY HIGHER POPS...BUT THE GFS CONTINUES TO SHOW VERY LITTLE MEASURABLE RAIN THIS EVENING...SO WILL WAIT FOR THE NEW GUIDANCE BEFORE INCREASING OR DECREASING POPS. WITH THE BREAKS IN CLOUD COVER...HIGHS SHOULD RECOVER TOE AROUND 60 THIS AFTERNOON. UPDATED LATEST HOURLY AND DEWPOINT GRIDS TO REFLECT CURRENT CONDITIONS. UPDATE ISSUED AT 735 AM EDT TUE APR 8 2014 UPDATED THE FORECAST TO SLOW DOWN THE ONSET OF PRECIPITATION FOR TODAY. ACCORDING TO THE MODELS...IT SHOULD BE RAINING NOW SO DECIDED TO HOLD OFF THE PRECIPITATION UNTIL THE UPPER TROUGH MOVES THROUGH THE AREA LATER TODAY. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 308 AM EDT TUE APR 8 2014 LOW CLOUDS HAVE SPREAD ACROSS THE AREA TONIGHT AS AN UPPER LEVEL DISTURBANCE WORKS ACROSS THE AREA. UNFORTUNATELY...THIS IS THE FIRST OF TWO UPPER TROUGHS WITH ANOTHER UPPER TROUGH EXPECTED TO MOVE ACROSS THE AREA TONIGHT. WITH THE UPPER TROUGH COMES SOME COLD AIR ALOFT. THIS WILL CAUSE THE CONDITIONS ACROSS THE AREA TO BE FAIRLY UNSTABLE THIS AFTERNOON AND EVENING. SO ALONG WITH SOME SCATTERED SHOWERS THAT ARE POSSIBLE...THERE MAY ALSO BE SOME ISOLATED THUNDERSTORMS. THESE ARE THE TYPE OF STORMS THAT WILL BE CAPABLE OF PRODUCING SOME GRAUPEL. HIGH PRESSURE WILL BE BUILDING INTO THE AREA ON WEDNESDAY. TEMPERATURES WILL REMAIN NEAR NORMAL DURING THE PERIOD WITH HIGHS IN THE 60S AND LOWS TONIGHT NEAR 40. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 358 AM EDT TUE APR 8 2014 MODELS CONTINUE TO SHOW GOOD AGREEMENT THROUGH THE MID TERM...AS THE PERIOD STARTS OFF WITH AN EXITING UPPER LEVEL TROUGH THURSDAY...AND A FLATTENING OF THE LONGWAVE PATTERN ACROSS KY. A SHALLOW TROUGHING PATTERN WILL TAKE SHAPE TO OUR NORTH...WITH A CLOSED LOW PASSING EASTWARD ACROSS SOUTHERN CANADA/GREAT LAKES REGION. EXPECT MUCH OF THE PRECIPITATION FROM THIS SYSTEM TO REMAIN TO OUR NORTH NEARER TO THE SURFACE LOW...WHICH WILL BE PASSING THROUGH JAMES BAY AND THEN NEWARD THURSDAY THROUGH THURSDAY NIGHT. HOWEVER...A ELONGATED SURFACE COLD FRONT WILL STRETCH FROM THIS LOW TO A WEAKER SURFACE LOW LOCATED OVER TX. WHILE THE ABOVE-MENTIONED NORTHERN CANADIAN LOW APPEARS TO BE VERY PROGRESSIVE...THE SOUTHERN LOW WILL REMAIN NEARLY STATIONARY. A LINE OF PRECIPITATION WILL DEVELOP ALONG THE LEADING EDGE OF THIS FRONTAL SYSTEM...FIRST MOVING FROM NW TO SE THROUGH KY THURSDAY NIGHT...AND THEN BECOMING ORIENTED FROM W TO E DUE TO THE NORTHERN LOW PROGRESSING MORE QUICKLY DURING THE DAY FRIDAY. SOME LOCALIZED SURFACE LOWS WILL ALSO DEVELOP ALONG THE LINE...HELPING TO BOOST INSTABILITY ACROSS EASTERN KY. LATEST GFS FORECAST SOUNDINGS ARE SHOWING GOOD POTENTIAL FOR CONVECTION WITHIN THIS PRECIPITATION...WITH GOOD FRONTAL LIFT...LOW LEVEL MOISTURE AND MID/UPPER LEVEL DRYING...AND DECENT SHEER. OBVIOUSLY...BEST TIMES FOR CONVECTION WILL BE IN THE AFTERNOON /FRIDAY/...WHEN DAYTIME HEATING ALLOWS ANY LOW LEVEL INVERSIONS TO BREAK AND MAXIMUM CAPE VALUES ARE REACHED. CAPE VALUES ARE MARGINAL...BUT EXPECT FRONTAL LIFT...LLVL WIND SHEAR...AND WARM BUOYANT PARCELS TO BE ABLE TO LIFT AND CREATE SOME TSTMS ACROSS THE AREA. THE W TO E ORIENTED FRONT WILL FINALLY MOVE S OF THE AREA SATURDAY...WITH ANY REMAINING PRECIPITATION ACROSS THE REGION COMING TO AN END AS SURFACE HIGH PRESSURE BRIEFLY RETURNS TO EASTERN KY. IN THE UPPER LEVELS...BRIEF RIDGING WILL TAKE HOLD AS WELL. HOWEVER...YET ANOTHER DEEPENING LOW IS EXPECTED ACROSS THE WESTERN PLAINS BY SUNDAY...WITH SEVERAL SMALLER SHORTWAVES DEVELOPING AS FAR EAST AS THE UPPER GREAT LAKES. MEANWHILE...IT IS ALSO AT THIS POINT THAT LONG RANGE MODELS START TO DIVERGE IN SOLUTIONS...SO WILL RELY ON THE ALLBLEND FOR ANY SURFACE PRECIP FEATURES AS FAR AS TIMING AND EXTENT/LOCATION. AT THE SURFACE...EXPECT A LOW PRESSURE SYSTEM TO DEVELOP OUT OF THIS SHORTWAVE ACROSS THE NORTHERN PLAINS ON SATURDAY...THEN SHIFT ENE TO THE UPPER GREAT LAKES BY LATE SATURDAY NIGHT. A COLD FRONT WILL EXTEND FROM THIS SURFACE LOW...BRINGING THE CHANCE FOR RAIN AND ENOUGH FRONTAL LIFT THAT SOME THUNDERSTORMS CANNOT BE RULED OUT AHEAD OF THE FRONT...WITH PRECIP EXPECTED TO ARRIVE SUNDAY NIGHT INTO MONDAY. WHILE THE PRECIP IS UNDERWAY MONDAY...LATEST ECMWF AND GFS40 SHOW THE UPPER LEVEL TROUGH CONTINUING TO DEEPEN AS IT MOVES EAST ACROSS THE CENTRAL PLAINS MONDAY...REACHING THE MISSISSIPPI RIVER VALLEY MONDAY NIGHT...AND THEN A CLOSED LOW DEVELOPING JUST TO THE SE OF KY BY TUESDAY NIGHT. WITH THAT...EXPECT PRECIP TO CONTINUE ACROSS KY INTO THE OVERNIGHT HOURS MONDAY NIGHT...WITH DRY AIR QUICKLY WORKING IN FROM THE NORTH BY 12Z TUESDAY JUST BEHIND THE FRONTAL PASSAGE THROUGH EASTERN KY. TOOK OUT ANY MENTION OF THUNDER AFTER 0Z TUESDAY...AS LATEST GFS40 SOUNDINGS SHOW AN IMPRESSIVE LOW LEVEL WARMING LAYER/INVERSION...AND WINDS UNSUPPORTIVE OF BEING ABLE TO LIFT PARCELS. OBVIOUSLY THIS FAR OUT IN THE FORECAST...THE TIMING OF SUCH FEATURES...AS WELL AS THE RESULTING POPS AND QPF...WILL NEED TO BE TWEAKED AND ADJUSTED AS WE HEAD CLOSER TO THE ONSET. HOWEVER...STILL FAIRLY IMPRESSED WITH THE AGREEMENT SO FAR BETWEEN THE GFS...GEM...AND ECMWF...AND FOR THE NAM IN THE MID TERM AS WELL. AS FAR AS TEMPERATURES...EXPECT LLVL WINDS TO REMAIN PREDOMINATELY OUT OF THE SOUTH DURING THE EXTENDED PERIOD...WITH THE EXCEPTION OF THE TWO FRONTAL PASSAGES. AS SUCH...DAYTIME HIGHS WILL CLIMB WELL ABOVE SEASONABLE NORMS MOST DAYS...INTO THE UPPER 60S AND LOW 70S. THE COLDEST DAYS WILL BE FRIDAY...AS THE FRONT BECOMES ELONGATED OVER KY AND COOLER AIR IS ALLOWED TO FILTER IN FROM THE NORTH...AS WELL AS AFTER THE FRONTAL PASSAGE AT THE END OF THE PERIOD...WHERE DAYTIME HIGHS ON TUESDAY WILL ONLY BOUNCE BACK INTO THE MID 50S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 735 AM EDT TUE APR 8 2014 LOW CLOUDS CONTINUE ACROSS THE AREA. THE MVFR CIGS HAVE RISEN IN THE SOUTHWESTERN PORTION OF THE AREA AND HAVE FORECAST THEM TO RISE AT JKL AND SJS IN THE NEXT COUPLE OF HOURS. COLD AIR STRATO CUMULUS WILL CONTINUE DURING THE DAY TODAY...BUT THEN WILL START TO DROP AGAIN AS THE NEXT UPPER TROUGH MOVES ACROSS THE AREA. THERE IS VERY COLD AIR ALOFT ASSOCIATED WITH THE UPPER TROUGH AND IT MAY BE ABLE TO CREATE SOME ISOLATED THUNDERSTORMS. THE VERTICAL PROFILE IS ALSO SUPPORTIVE OF SOME SMALL HAIL/GRAUPEL. THIS HAIL IS POSSIBLE WITH THUNDERSTORMS OR JUST WITH RAIN SHOWERS. THE PRECIPITATION SHOULD CONTINUE THROUGH THE END OF THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...JJ LONG TERM...JMW AVIATION...JJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1003 AM EDT TUE APR 8 2014 .SYNOPSIS... A COLD FRONT MOVES OFF THE MID ATLANTIC COAST TODAY. A TROUGH OF LOW PRESSURE LINGERS ALONG THE COAST THROUGH TONIGHT. HIGH PRESSURE BUILDS BACK INTO THE AREA WEDNESDAY THROUGH FRIDAY. A COLD FRONT APPROACHES FROM THE NORTH FRIDAY NIGHT. && .NEAR TERM /THROUGH TONIGHT/... A SLOW FRONT WILL SLOWLY MOVE THROUGH THE AREA THIS AFTERNOON. WITH THE UPPER FLOW STILL SOUTHWEST AS CAN BE SEEN ON VWP AND SOME PROFILERS THE FRONT WILL MOVE EVEN SLOWER AS IT PUSHES TO THE COAST. RADAR CONTINUES TO SHOW SHOWERS OVER NORTHEAST NORTH CAROLINA. THE HRRR AND RUC DEPICTS THESE ECHOES WELL ON ITS SIMULATED REFLECTIVITY AND THIS SHOWS THE ECHOES VERY SLOWLY SINKING SOUTHEAST. CHANGED POPS TO KEEP THEM A LITTLE HIGHER LONGER ESPECIALLY OVER NORTHEAST NORTH CAROLINA. MILD WITH TEMPERATURES CHANGING VERY LITTLE AND HIGHS MID 60S TO LOW 70S. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... TROF SHIFTS EAST TONIGHT BUT YET ANTHR IN A SERIES OF UPPER LEVEL DISTURBANCES APPRCHS FROM THE WEST AFTR MIDNITE. EXPECT MOST OF THIS MSTR TO GO INTO CLOUD COVERAGE...SO KEPT THE FCST DRY FOR NOW. ANY PCPN THAT DOES DVLP SHOULD STAY IN NC. LOWS IN THE 40S. HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST WED. BEFORE ANY DRYING OCCURRS...LAST OF THE S/W`S PROGGED TO TRACK ACROSS NC DURING THE AFTRN. BOTH GFS/NAM SHOW MINIMAL AMTS OF MSTR ACROSS SRN CNTYS. GIVEN THIS MSTR MOVES THRU DRNG PEAK HEATING HRS...ADDED ISLTD SHWRS TO SRN CNTYS (MAINLY S OF RT 58). HIGHS IN THE 60S. ERN TROF FINALLY LIFTS OUT ALLOWING RIDGING TO SETTLE IN ACROSS THE AREA WED NITE AND THURS. TSCTNS VOID OF ANY SGNFCNT MSTR SO EXPECT A M CLR TO PT CLDY PRD. WEAK CAA DMNSHS SETTING UP DECENT RADIATIONAL COOLING WED NITE. LOWS M-U30S NRN/WRN CNTYS TO U30S-L40S SRN AREAS. PT TO MSTLY SUNNY THURSDAY. HIGHS U60S-L70S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... SEASONABLY WARM TEMPERATURES WILL HEADLINE THE EXTENDED PERIOD FORECAST WITH CHANCES OF SHOWERS EARLY NEXT WEEK. ZONAL FLOW ALOFT TO BEGIN THE EXTENDED AS A SHORTWAVE TRACKS ACROSS SE CANADA THURS NIGHT-FRI MORNING. THIS WILL PUSH A WEAK COLD FRONT TOWARD THE CTRL APPALACHIANS FRI. HIGH PRESSURE WILL CENTER OVER THE WRN ATLANTIC FRI...RIDGING SWWD INTO THE GULF STATES. HIGH PRESSURE AND WLY FLOW ALOFT WILL LIMIT ANY RETURN MOISTURE REGARDLESS OF SLY FLOW ON THE BACK SIDE OF THE SFC HIGH. THIS WILL KEEP THE LOCAL AREA DRY ON FRI. CYCLONIC FLOW WILL INCREASE OVER THE ERN CONUS FRI AS NRN STREAM ENERGY DIGS OVER THE MIDWEST. MODELS DEVELOP A WAVE ALONG THE FRONT OVER NRN VA/MD... WHICH MAY ENHANCE RAINFALL IN THAT REGION. WILL MAINTAIN SLIGHT CHANCE-LOW END CHANCE POPS OVER THE NRN LOCAL AREA...INCLUDING THE MD ERN SHORE FRI-FRI NIGHT. MODELS THEN DIFFER ON PUSHING THE WEAK FRONT THROUGH THE LOCAL AREA SAT. TRENDED TOWARD THE GFS...THINKING THE FRONT WILL HAVE TROUBLE PUSHING THROUGH THE REGION. ECMWF MORE ROBUST WITH SHORTWAVE TRAVERSING THE REGION FRI NIGHT-THURS MORNING...PUSHING THE FRONT THRU THE LOCAL AREA. REGARDLESS OF WHICH MODEL VERIFIES...LACK OF MOISTURE AND DYNAMICS...AS WELL AS SUBSIDENCE BEHIND THE FRONT WILL KEEP THE FORECAST DRY SAT. SUNDAY WILL ALSO BE DRY AS HIGH PRESSURE/SUBSIDENCE DOMINATES. MEANWHILE... A DEEPENING TROUGH OVER THE WRN CONUS/INTERMOUNTAIN WEST WILL AMPLIFY THE FLOW OVER THE ERN CONUS. AN ASSOCIATED COLD FRONT WILL PROPAGATE EWD OVER THE MIDWEST INTO THE OH VALLEY SUN NIGHT-MON MORNING. MEANINGFUL DIFFERENCES EXIST IN THE MODELS...WITH THE GFS 12+ HRS FASTER WITH THE FRONT/MOISTURE THAN ITS ECMWF COUNTERPART. HAVE OPTED FOR SLIGHT CHANCE-LOW END CHANCE POPS BEGINNING MON TO ACCOUNT FOR UNCERTAINTY. DAYTIME TEMPS WILL BE SEASONABLY WARM...GENERALLY IN THE LOW-MID 70S. SLIGHTLY COOLER SAT WITH FRONTAL PASSAGE AND NLY WINDS. SLY WINDS FRI AND SUN-MON WILL RESULT IN LOCALLY COOLER TEMPS ALONG THE COASTAL ERN SHORE. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... MVFR TO MARGINAL IFR CONDITIONS WILL CONTINUE THROUGH 14Z AS LOW CLOUDS CONTINUE TO SCOUR OUT. A LITTLE -RA WILL ALSO MAKE ITS WAY THROUGH SE VA AND NE NC THROUGH 15Z. WEST WINDS DEVELOP BEHIND A COLD FRONTAL PASSAGE LATE THIS MORNING INTO THE AFTERNOON AND CONDITIONS WILL IMPROVE TO VFR BY LATE MORNING. OUTLOOK...HIGH PRESSURE BUILDS INTO THE REGION WITH MAINLY VFR AND DRY THE REST OF THE WEEK. && .MARINE... A COLD FRONT WILL CROSS THE WATERS LATE THIS MORNING INTO THE AFTERNOON WITH WINDS BECOMING W-NW BY AFTN AND N-NW TONIGHT. WINDS REMAIN AOA SCA THRESHOLDS THRU NOON BEFORE DIMINISHING TO 10-15 KT OR LESS THIS AFTERNOON. LACK OF CAA AND STRONG GRADIENT WINDS (HIGH PRESSURE BUILDING IN FROM THE SW) WILL PRODUCE SUB-SCA WINDS (AOB 15 KT) OVER THE WATERS TONIGHT. SEAS WILL BE SLOW TO SUBSIDE ACROSS THE NORTHERN WATERS TODAY...BUT SHOULD DROP BELOW 5 FT AROUND OR SHORTLY AFTER 8 PM. SEAS ACROSS THE SOUTHERN WATERS MAY DROP BELOW 5 FT AS EARLY AS NOON TODAY DUE TO SW FLOW REGIME AND MAY BE ABLE TO DROP SCA`S QUICKER THAN CURRENTLY FORECAST. WILL CONTINUE TO MONITOR AND ADJUST HEADLINES AS NECESSARY. HIGH PRESSURE BUILDS OVER THE WATERS WEDS-THURS RESULTING IN SUB-SCA CONDITIONS. A WEAK COLD FRONT WILL APPROACH THE WATERS THURSDAY NIGHT-EARLY FRI MORNING...LIKELY STALLING OVER OR JUST NORTH OF THE REGION FRI. && .HYDROLOGY... RECENT RAINFALL OF 1 TO 1.5 INCHES HAS CAUSED AREA RIVERS TO RISE ONCE AGAIN...MAINLY BTWN 1/2 TO 3/4 BANKFULL...GREATEST ACROSS SOUTHERN MAIN STEM RIVERS. THE FRANKLIN STAGE ON THE BLACKWATER HAS REACHED CAUTION STAGE. WHILE LAWRENCEVILLE ON THE MEHERRIN RIVER WILL GO TO MINOR FLOODING. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ650-652- 654. SMALL CRAFT ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR ANZ634. && $$ SYNOPSIS...MPR NEAR TERM...MPR/JAB SHORT TERM...MPR LONG TERM...SAM AVIATION...JDM MARINE...JDM HYDROLOGY... TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
753 AM EDT TUE APR 8 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 505 AM EDT TUE APR 8 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA AND A TROF EXTENDING FROM HUDSON BAY TO THE WRN GULF OF MEXICO. STRONG SHORTWAVE THAT WAS OVER THE SRN PLAINS 24HRS AGO IS NOW MOVING THRU THE LOWER GREAT LAKES. CLOSER TO HOME...SHORTWAVE OVER WRN UPPER MI HAS BEEN GENERATING PESKY -SHRA FROM ISLE ROYALE ACROSS THE KEWEENAW PENINSULA DURING THE NIGHT. THE -SHRA ARE DRIFTING SSE INTO PORTIONS OF CNTRL UPPER MI ATTM. MID CLOUDS ASSOCIATED WITH SHORTWAVE HAVE WORKED TO LIMIT FOG. OVER THE NEXT SEVERAL HRS...UTILIZED MOSTLY EXTRAPOLATION/TRENDS TO SHIFT AN AREA OF ISOLD/SCT -SHRA SSE FROM THE KEWEENAW TOWARD SCNTRL UPPER MI BEFORE THE -SHRA DISSIPATE. WHERE THE -SHRA ARE OCCURRING...TEMPS WILL STAY ABOVE FREEZING. IN THE WAKE OF THE -SHRA...THERE IS STILL AN OPPORTUNITY FOR -DZ/-FZDZ TO DEVELOP THIS MORNING. BEST CHC SHOULD BE OVER WRN UPPER MI. DWPT AT DISW4 IS STILL AROUND 35F. AS THIS HIGHER DWPT AIR OVER THE LAKE ADVECTS SSE INTO WRN UPPER MI WHERE SFC TEMPS ARE AT OR BLO FREEZING...STRATUS/FOG AND POTENTIALLY -FZDZ SHOULD DEVELOP. THEREAFTER...EXPECT INCREASING SUNSHINE DURING THE AFTN AS DRIER AIR ARRIVES...BREAKING UP CLOUD COVER. IT WILL BE A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR. OVER THE E WHERE THERE WILL BE A BRISK WIND ACROSS THE LAKE...TEMPS SHOULD HOLD MOSTLY IN THE LWR 30S TODAY. OTHERWISE...EXPECT GENERALLY 30S AND LWR 40S N TO AROUND 50 FAR SCNTRL FROM KIMT TO NEAR KMNM. SFC HIGH PRES RIDGE SHIFTS ACROSS THE UPPER LAKES TONIGHT... PROVIDING LIGHT/CALM WINDS FOR A GOOD PORTION OF THE NIGHT IN MOST AREAS. ON THE BACKSIDE OF THE RIDGE AND IN ADVANCE OF SHORTWAVE MOVING ACROSS THE SRN CANADIAN ROCKIES...STRENGTHENING WAA/ISENTROPIC ASCENT PATTERN TO THE NW WILL GENERATE SOME PCPN ACROSS MANITOBA INTO NRN ONTARIO TONIGHT. ALTHOUGH HIGH/MID CLOUDS WILL SPREAD SE INTO THE AREA OVERNIGHT...THERE SHOULD BE A LONG ENOUGH PERIOD OF MOSTLY CLEAR SKIES TO ALLOW A DECENT TEMP FALL. LOWERED MINS TOWARD THE LOW END OF AVBL GUIDANCE...REPRESENTED BY THE BIAS CORRECTED REGIONAL AND GLOBAL GEM. TRADITIONAL INTERIOR COLD SPOTS SHOULD FALL TO THE MID TEENS AND PERHAPS EVEN TO THE LOW TEENS OVER THE E. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 416 AM EDT TUE APR 8 2014 AFTER A COOLER DAY TODAY...WEDNESDAY WILL TRANSITION BACK TO THE ABOVE NORMAL TEMPERATURES SEEN OVER THE LAST COUPLE OF DAYS. THIS IS DUE TO AN UPPER RIDGE CURRENTLY OVER THE WESTERN CONUS SHIFTING EAST INTO THE GREAT LAKES REGION FOR WEDNESDAY AND WEDNESDAY NIGHT. AS THIS RIDGE MOVES IN...EXPECT A STRONG AREA OF WARM AIR ADVECTION AND Q-VECTOR CONVERGENCE SHIFTING EAST-SOUTHEAST ALONG THE US/CANADIAN BORDER (AND ACROSS THE NORTHERN HALF OF THE CWA) LATE TONIGHT THROUGH EARLY WEDNESDAY AFTERNOON. FOR MUCH OF THE LAND CWA...WOULD EXPECT THERE TO JUST BE SOME PASSING MID CLOUDS. BUT THERE MAY BE ENOUGH MOISTENING IN THE LOWER LEVELS TO ALLOW SOME LIGHT SPRINKLES TO AFFECT THE KEWEENAW PENINSULA. OTHERWISE...THIS AREA OF FORCING WILL QUICKLY SHIFT THROUGH AND SHOULD LEAD TO A FILTERED SUNSHINE OVER THE AREA DUE TO HIGH CLOUDS AHEAD OF THE NEXT SYSTEM. STRONG WARMING IN THE LOWER LEVELS THROUGH THE DAY ON WEDNESDAY (850MB TEMPS RISING FROM -4C AT 06Z TO AT LEAST 6C AT 00Z THURSDAY) SHOULD LEAD TO ANOTHER WARM DAY ACROSS THE CWA. WILL CONTINUE TO SHOW HIGHS IN THE UPPER 50S AND LOWER 60S OVER THE WESTERN HALF OF THE CWA AND LOWER VALUES (40S) OVER THE EAST WITH THE SOUTHWEST WINDS OFF LAKE MICHIGAN. SPEAKING OF THOSE WINDS...THEY LOOK TO BE A LITTLE GUSTY IN THE AFTERNOON (15-25KTS) AND THAT WILL ALLOW THE DOWNSLOPE AREAS TO WARM AND LIMIT LAKE BREEZE COOLING. WHILE THE WARMING IS OCCURRING ON WEDNESDAY...A SURFACE LOW WILL BE SHIFTING EAST THROUGH FAR NORTHERN ONTARIO AND A COLD FRONT WILL STRETCH SOUTHWEST INTO THE UPPER MISSISSIPPI VALLEY. MODELS REMAIN CONSISTENT ON THE TIMING OF THIS COLD FRONT MOVING THROUGH THE CWA DURING THE OVERNIGHT HOURS WEDNESDAY NIGHT AND FOR THE FIRST PART OF THURSDAY MORNING. MODELS ARE INDICATING THE BEST FORCING ALONG THE FRONT TO DIVE TO THE SOUTHEAST THROUGH WISCONSIN...BUT WILL HOLD ONTO CHANCE POPS DUE TO THE EXPECTED EASTWARD MOVEMENT OF THE UPSTREAM SHOWERS. STEEP MID LEVEL LAPSE RATES AND SHOWALTER VALUES AROUND 0 COULD PRODUCE A RUMBLE OF THUNDER OVER WESTERN LAKE SUPERIOR AND HAVE ADDED A SLIGHT CHANCE TO THE FAR WEST. WITH THE SHORTWAVE WELL BEHIND THE FRONT AND ONLY A VERY THIN LINE OF MOISTURE...EXPECT QPF AMOUNTS TO STAY BELOW 0.15IN IN MOST LOCATIONS. MOST OF THESE SHOWERS SHOULD SHIFT OUT OF THE CWA BY THE AFTERNOON. TEMPERATURES ALOFT COOL SOME BEHIND THE FRONT...BUT STILL LOOK TO BE AROUND 0C TO -2C AT 850MB. THOSE TEMPS COMBINED WITH SUNSHINE BEHIND THE FRONT WILL YIELD HIGHS IN THE UPPER 40S TO MID 50S. WITH A HIGH PRESSURE RIDGE SLIDING THROUGH THE AREA ON THURSDAY NIGHT...DRY CONDITIONS ARE EXPECTED AND TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S. FRIDAY LOOKS TO BE DRY OVER MUCH OF THE CWA...BUT THERE ARE A COUPLE SUBTLE FEATURES TO NOTE. FIRST...A SECONDARY SURFACE TROUGH TRIES TO BRUSH THE NORTHEAST THIRD OF THE CWA FRIDAY MORNING...BUT IT DOESN/T LOOK LIKE IT WILL MAKE IT THAT FAR INTO LAKE SUPERIOR. SECOND...A WEAK SHORTWAVE AND ASSOCIATED SURFACE TROUGH LOOKS TO SHIFT EAST THROUGH UPPER MICHIGAN AND WISCONSIN FRIDAY AFTERNOON/ EVENING AND COULD KICK OFF A SHOWER OR TWO. GFS IS BY FAR THE STRONGEST WITH THE WAVE BUT MOISTURE SEEMS TO BE VERY LIMITED. WILL TREND POPS UP TO LOW END SLIGHT CHANCES FOR THE AFTERNOON/EVENING...BUT CONFIDENCE IS LOW. FOR THE WEEKEND...FOCUS IS ON TWO UPPER LEVEL FEATURES THAT WILL BE OVER THE WESTERN CONUS ON FRIDAY NIGHT...ONE NEAR SOUTHERN CALIFORNIA AND THE OTHER IN THE PACIFIC NORTHWEST. THE LEADING PIECES OF ENERGY ASSOCIATED WITH THESE WAVES WILL PUSH THE FIRST WAVE OF PRECIP ACROSS THE AREA ON SATURDAY. THIS PRECIP WILL BE ASSOCIATED WITH AN ELONGATED TROUGH STRETCHING NORTHEAST FROM THE CENTRAL/SOUTHERN ROCKIES. MODELS STILL SHOWING A WIDE VARIETY OF SOLUTIONS FOR THE LOCATION OF THE TROUGH WITH THE GFS/GEM FAST/SE ECMWF FARTHEST NORTHWEST. A GENERAL BLEND WILL WORK WELL AT THIS POINT FOR POPS (CHANCES)...MOVING INTO THE WESTERN CWA SATURDAY MORNING AND SHIFTING EAST OVER THE REST OF THE AREA IN THE AFTERNOON. THE LOCATION OF THE ELONGATED TROUGH HAS A INFLUENCE ON THE WEATHER FOR THE REGION FOR THE SECOND HALF OF THE WEEKEND AND INTO MONDAY. BY THAT POINT...THE TWO WAVES THAT ARE ALONG THE WEST COAST WILL HAVE MERGED OVER THE CENTRAL CONUS AND WILL BE SHIFTING EAST. THESE FEATURES WILL BE HELPED BY A THIRD DISTURBANCE THAT WILL DROP SOUTHEAST FROM CANADA. THE TIMING OF THESE THREE FEATURES AND HOW FAR EAST THEY END UP WILL DETERMINE PRECIP CHANCES (AND MEASURABLE SNOW POSSIBILITY) FOR PARTS OF THE CWA. AS HAS BEEN THE CASE FOR THE LAST COUPLE DAYS...THE GFS IS THE FARTHEST EAST AND THE ECMWF IS THE FARTHEST WEST WHILE THE 00Z GEM IS NOW SIMILAR TO . THE GFS. WITH THE PHASING OF SEVERAL SHORTWAVES...CONFIDENCE IN ANY ONE SOLUTION IS VERY LOW AND MODELS WILL BE HIGHLY VARIABLE OVER THE NEXT COUPLE DAYS. AT THIS POINT...WILL HAVE THE HIGHER CHANCE POPS OVER THE SOUTHEAST HALF OF THE CWA...WHERE A GENERAL CONSENSUS WOULD INDICATE PRECIP. WITH THE EXPECTED COLD AIR THAT WILL SPILL IN BEHIND THE TROUGH ON SUNDAY...WOULD EXPECT THE PRECIP TO TRANSITION TO SNOW AND THERE COULD BE SOME ACCUMULATION IF THE 12Z ECMWF IS CORRECT. IN ADDITION...THE LOW LEVEL COLD AIR SURGING IN AT THE SURFACE WITH THE NORTHERLY WINDS COULD PRODUCE A 6HR PERIOD OF FREEZING RAIN. WAY TO FAR OUT TO GET TOO EXCITED AT THAT POTENTIAL AT THIS POINT...BUT IT IS SOMETHING TO WATCH. THE FIRST HALF OF NEXT WEEK LOOKS TO BE BELOW NORMAL TEMPERATURE WISE ACROSS THE GREAT LAKES REGION...AS THE UPPER LEVEL PATTERN RESEMBLES THE ONE FROM MUCH OF THIS PAST WINTER. 850MB TEMPS DO LOOK TO FALL TOWARD -12C TO -17C FOR A SHORT PERIOD DURING THE FIRST HALF OF THE WORK WEEK AND THAT COULD LEAD TO HIGHS AROUND FEEZING ON TUESDAY. FOR THOSE THAT HAVE BEEN ENJOYING THE SPRING LIKE TEMPERATURES OVER THE LAST COUPLE OF DAYS...IT APPEARS THIS TROUGH WILL LIFT OUT OF THE AREA ON WEDNESDAY AND RETURN THE AREA BACK TO NORMAL TEMPERATURES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 752 AM EDT TUE APR 8 2014 COLD AIR ADVECTION AND MID CLOUDS HAVE LIMITED POTENTIAL FOR LOW CLOUDS/FOG/-DZ/-FZDZ FOR THE REST OF THE MORNING...BUT DAYTIME HEATING MAY YIELD MVFR CIGS FOR A TIME THIS MORNING AT KIWD/KSAW. OTHERWISE...VFR CONDITIONS SHOULD BE THE RULE THRU THIS FCST PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 505 AM EDT TUE APR 8 2014 AS PRES GRADIENT TIGHTENS BTWN APPROACHING HIGH PRES RIDGE AND DEEPENING LOW PRES MOVING FROM THE LWR LAKES TO NEW ENGLAND...WINDS WILL PICK UP ACROSS LAKE SUPERIOR THIS MORNING...BUT MAINLY OVER THE ERN PORTION OF THE LAKE WHERE WINDS SHOULD INCREASE TO 15-25KT. WINDS WILL DIMINISH TONIGHT AS THE HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEP LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. WINDS WILL REACH THE 20-30KT RANGE...AND NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS WILL REACH GALE FORCE AT SOME POINT WED/THU. STABLE LOW-LEVEL TEMP PROFILE WILL WORK AGAINST STRONGER WINDS...BUT HEALTHY PRES FALLS AHEAD OF LOW WED AND HEALTHY PRES RISES ARRIVING BEHIND TROF PASSAGE WED NIGHT/THU MORNING MAY BE WHAT PUSHES WINDS TO GALE FORCE FOR A TIME. WINDS WILL THEN DIMINISH THU NIGHT/FRI. INCREASING WINDS ARE EXPECTED FOR THE WEEKEND AS LOW PRES TROF APPROACHES AND THEN MOVES ACROSS THE AREA. && .HYDROLOGY... ISSUED AT 416 AM EDT TUE APR 8 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN UPPER MICHIGAN HAS RIPENED AND WOULD EXPECT THE ABOVE NORMAL TEMPERATURES TODAY TO INCREASE SNOWMELT. COOLER TEMPERATURES ARRIVING ON TUESDAY (INCLUDING LOWS WELL BELOW FREEZING TUESDAY NIGHT) WILL LEAD TO REDUCED SNOWMELT DURING THAT PERIOD...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS OVER THE FIRST HALF OF THIS WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...SRF AVIATION...ROLFSON MARINE...ROLFSON HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS JACKSON MS
1045 AM CDT TUE APR 8 2014 .UPDATE...FORECAST FOR TODAY UPDATED TO ADJUST TEMPERATURES AND ADJUST TIMING OF SHOWER AND THUNDERSTORM PROBABILITIES THROUGH MIDDAY. OTHER ADJUSTMENTS MINOR. /BB/ && .DISCUSSION...FOCUSED LIFT ASSOCIATED WITH MID TO UPPER LEVEL DEEP TROUGH AXIS OVER THE AREA IS FORCING A NORTH TO SOUTH ORIENTED BAND OF SHOWERS CURRENTLY MOVING TOWARD THE I-55 CORRIDOR. THERE HAS THUS FAR BEEN VERY LITTLE TO NO LIGHTNING ACTIVITY ASSOCIATED WITH THESE SHOWERS. HIRES MODEL OUTPUT SUGGESTS THIS BAND CONTINUING TO PROGRESS EAST INTO THE AFTERNOON AND EXITING INTO ALABAMA BY MID TO LATE AFTERNOON. MORNING REGIONAL SOUNDINGS SUGGESTS CONVECTIVE TEMPERATURES WILL BE REACHED WHEN SURFACE TEMPS HIT THE 60 TO 65 DEGREE RANGE...WHICH WILL HAPPEN IN PATCHES OVER THE NEXT FEW HOURS EVEN GIVEN RATHER EXTENSIVE CLOUD COVER. THEREFORE...ANTICIPATE AT LEAST SOME MIXING IN OF THUNDERSTORMS WITH MENTIONED SHOWER BAND AS IT PROGRESSES EAST INTO THE AFTERNOON. IN THE WAKE OF THE BAND THERE STILL WILL BE AN IMPULSE OR TWO LEFT TO SWING RAPIDLY DOWN THE WESTERN SIDE OF THE TROUGH OVER OUR REGION...WHICH SHOULD KICK UP AT LEAST SCATTERED SHOWERS AND STORMS INTO THE AFTERNOON IN WESTERN AND CENTRAL ZONES. HIRES HRRR OUTPUT SUGGESTS SOME OF THIS LATTER ACTIVITY COULD PRODUCE SWATHS OF GUSTY WINDS THROUGH 6 TO 7 PM...POSSIBLY OVER 50 MPH...WHICH IS SOMETHING WE WILL HAVE TO KEEP A CLOSE EYE ON. OTHERWISE...THE PREVIOUS FORECAST AND HAZARDOUS WEATHER OUTLOOK HAD A VERY GOOD HANDLE OF THE SITUATION AND NO LARGE ADJUSTMENTS ARE NEEDED. HAIL POTENTIAL AS ADVERTISED SHOULD FAVOR SMALL HAIL SIZES ALTHOUGH A TOP END STORM FOR THE ENVIRONMENT MAY ACHIEVE SOME STONES TO THE SIZE OF QUARTERS. ONE FINAL COMMENT IS THAT LATEST HRRR OUTPUT SHOWS SOME CLUSTERS OF SHOWERS AND STORMS THIS AFTERNOON WHICH WOULD HAVE THE POTENTIAL FOR HEAVY DOWNPOURS...WHICH IS NOT GOOD NEWS CONSIDERING FLOODING SITUATION ONGOING IN PORTIONS OF THE REGION. HOWEVER...LIKELIHOOD OF RAINFALL TOTALS TODAY EXCEEDING AN INCH ARE VERY LOW AND TODAY`S RAINFALL IN GENERAL IS STILL NOT EXPECTED TO SIGNIFICANTLY WORSEN ANY CURRENT FLOODING. /BB/ && .PREV DISCUSSION... /ISSUED 435 AM CDT TUE APR 8 2014/ DISCUSSION... TODAY THROUGH WEDNESDAY NIGHT... HYDROLOGY...MODERATE RAINFALL AMOUNTS OF ONE QUARTER TO ONE HALF INCH ARE EXPECTED ON AVERAGE TODAY WITH LOCAL AMOUNTS TO ONE INCH POSSIBLE. THIS RAINFALL IS NOT EXPECTED TO BE HEAVY ENOUGH TO SERIOUSLY AGGRAVATE THE CURRENT FLOODING SITUATION...BUT ANY RAIN AT THIS POINT WILL RUN OFF QUICKLY AND POSSIBLY SLOW DOWN THE DRAINAGE PROCESS. /EC/ THERE ARE NO SIGNIFICANT CHANGES REGARDING THE SET-UP FOR TODAY`S MARGINAL SEVERE WEATHER RISK. AN IMPRESSIVELY COLD MID/UPPER LEVEL TROUGH WITH H500 TEMPERATURES ~ -25 DEG C WILL MOVE EAST ACROSS THE LOWER MS VALLEY REGION TODAY. EXPECT A LINE OF SHOWERS AND A FEW THUNDERSTORMS TO INCREASE IN ASSOCIATION WITH LIFT JUST AHEAD OF THE TROUGH AXIS AND MOVE INTO WESTERN PORTIONS OF THE ARKLAMISS BY MID MORNING AND INTO EASTERN MS BY EARLY AFTERNOON. JET ENERGY DIGGING SOUTHWARD AROUND THE WESTERN SIDE OF THE TROUGH WILL ENHANCE CYCLONIC FLOW AND PROVIDE SUPPORT FOR ADDITIONAL SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT THIS AFTERNOON. MOISTURE IS LIMITED...BUT THE TIMING OF THE TROUGH PASSAGE WILL LINE UP WITH MAXIMUM DAYTIME HEATING TO PRODUCE STEEP LOW-MID LEVEL LAPSE RATES AND SURFACE-BASED CAPE LIKELY EXCEEDING 700 J/KG. THIS COMBINATION OF LIFT AND INSTABILITY WILL YIELD LOW-TOP NEAR SURFACE- BASED THUNDERSTORMS. GIVEN LOW WET BULB ZERO HEIGHTS AROUND 6000 FT..SMALL HAIL WILL BE POSSIBLE WITH JUST ABOUT ANY STORM AND STRONG WIND GUSTS COULD CERTAINLY MIX DOWN GIVEN STEEP SUB-CLOUD LAPSE RATES/ENHANCED DOWNDRAFTS AND 30-35KTS OF LOW-MID LEVEL FLOW DEVELOPING IN THE AFTERNOON. WILL CONTINUE THE HAZARD PRODUCTS AS THEY ARE WITH A MENTION OF MARGINALLY SEVERE HAIL AND 40-50 MPH WIND GUST POTENTIAL. AS WE GO INTO TONIGHT...EXPECT RAPID DIMINISHING OF THE THUNDERSTORM POTENTIAL WITH LOSS OF DAYTIME HEATING AND LIFT ASSOCIATED WITH THE DEPARTING TROUGH. THIS WILL BE FOLLOWED BY A RETURN TO DRY BUT SEASONABLY COOL CONDITIONS THROUGH WEDNESDAY NIGHT. /EC/ THURSDAY THROUGH NEXT TUESDAY...QUIET WEATHER IS CURRENTLY FORECAST FROM THURSDAY THROUGH AT LEAST THE FIRST HALF OF THE UPCOMING WEEKEND AS HIGH PRESSURE BUILDS THROUGH THE FORECAST AREA. SOUTHERLY FLOW AT THE SURFACE AS HIGH PRESSURE POSITIONS ITSELF EAST OF THE REGION...AND QUASI-ZONAL FLOW ALOFT...WILL CAUSE CONDITIONS TO GRADUALLY WARM AND MOISTEN THROUGH THE WEEKEND. CLOUDS AND RAIN CHANCES WILL BE ON THE INCREASE THROUGH SUNDAY AFTERNOON AND INTO MONDAY AS ANOTHER SYSTEM IS PROGGED TO PUSH INTO AND THROUGH THE CWA. JUST AS THE CASE WAS LAST NIGHT...THERE ARE SOME DISAGREEMENTS IN HOW THE GFS AND ECMWF DEVELOP THIS SYSTEM. HOWEVER...BOTH AGREE WITH THEIR TIMING OF SAID SYSTEM IN BRINGING IT INTO THE FORECAST AREA LATE SUNDAY NIGHT AND EXITING IT MONDAY EVENING...WITH RAIN COMING TO AN END MONDAY NIGHT. BEHIND THIS SYSTEM...A COOLER DRIER AIRMASS IS EXPECTED TO ADVECT SOUTH INTO THE FORECAST AREA ON TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. /19/ && .AVIATION...MOSTLY VFR CEILINGS WILL PREVAIL TODAY DESPITE SCATTERED SHOWERS THROUGH THE AFTERNOON AND ENDING SHORTLY AFTER 09/00Z. SOME MVFR VISIBILITIES WILL EXIST THIS AFTERNOON AT THOSE LOACTIONS THAT MANAGE TO SEE SHOWERS. VFR CONDITIONS SHOULD EXIST FOR THE MAJORITY OF THE NIGHT...BUT SOME MVFR VISIBILITIES WILL BE POSSIBLE IN THE 10-14Z TIMEFRAME FROM FOG./26/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 64 41 67 43 / 68 27 0 0 MERIDIAN 65 40 68 38 / 70 42 0 0 VICKSBURG 63 41 67 41 / 73 15 0 0 HATTIESBURG 69 44 69 41 / 70 35 0 0 NATCHEZ 65 40 65 43 / 63 20 0 0 GREENVILLE 63 43 67 45 / 80 15 0 0 GREENWOOD 66 43 67 44 / 70 26 0 0 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/26/EC/19
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1105 AM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL PUSH EAST ACROSS CENTRAL NC THIS AFTERNOON. AN UPPER LEVEL TROUGH WILL APPROACH THE AREA TONIGHT AND SWING THROUGH THE AREA LATE WEDNESDAY. HIGH PRESSURE CENTERED OVER THE GULF OF MEXICO AND THE SOUTH ATLANTIC WILL EXTEND INTO THE REGION ON THURSDAY AND FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1105 AM TUESDAY... AT 1100 AM THE SURFACE COLD FRONT WAS ANALYZED FROM JUST WEST OF ROANOKE RAPIDS TO RALEIGH TO NEAR WADESBORO. MUCH DRIER AIR IS SPILLING INTO THE REGION BEHIND THE FRONT WITH DEWPOINTS DOWN INTO THE LOWER 40S ACROSS THE TRIAD WHILE AHEAD OF THE FRONT...DEW POINTS ARE IN THE MID 60S ACROSS THE SOUTHERN COASTAL PLAIN. EVEN WITH MOIST DEW POINTS...INSTABILITY IS RATHER LACKING BASED ON THE MOST RECENT SPC MESOANALYSIS. RECENT RADAR IMAGERY SHOWS A FEW SHOWERS DEVELOPING AHEAD OF THE FRONT ACROSS JOHNSTON AND WILSON COUNTIES WITH LIGHT TO MODERATE RETURNS. RECENT HRRR RUNS NOTED THE POTENTIAL FOR THESE SHOWERS BUT INDICATED A LIMITED AERIAL OVERAGE AND INTENSITY. SATELLITE IMAGERY AND SURFACE OBSERVATIONS NOTE A DECREASE IN THE LOW LEVEL MOISTURE AND CLOUDS BEHIND THE COLD FRONT WITH A FAIRLY THICK VEIL OF HIGH LEVEL CLOUDS ASSOCIATED WITH A STOUT 165+KT JET ALOFT. THE PRIO MORNING UPDATE TRIMMED POPS DOWN TO JUST THE SOUTHEAST PORTION OF THE CAW FOR THIS MORNING AND MADE ADJUSTMENTS TO CLOUD AND TEMPERATURE TRENDS. TEMPERATURE FORECASTS FOR THIS AFTERNOON WILL BE PROBLEMATIC WITH THE COUNTERACTIVE INFLUENECES OF INCREASING SUNSHINE AND SOME SLIGHT COLD ADVECTION. LEANED HEAVILY UPON THE HRRR HOURLY TEMPERATURE GUIDANCE WHICH RESULTED IN MAX TEMPERATURES IN THE MID TO UPPER 60S IN THE TRIAGE AND THE LOWER 70S ELSEWHERE. -BLAES TONIGHT AND WEDNESDAY: EXPECT A SERIES OF EMBEDDED S/W`S IN THE DEEP TROUGH ALOFT WILL CROSS THE REGION AS THE DEEP TROUGH ITSELF SHIFTS EASTWARD AND ACROSS THE AREA THROUGH WEDNESDAY. THIS WILL RESULT IN PERIODS OF PARTLY TO MOSTLY CLOUDY/CLOUDY SKIES. EXPECT WE WILL GENERALLY REMAIN DRY THOUGH. HOWEVER... WITH 500 MB HEIGHTS FALLING SOME 150 METERS BETWEEN NOW AND WEDNESDAY MORNING WE WILL SEE OUR INSTABILITY ALOFT INCREASE... WITH POSSIBLY SOME SHOWERS DEVELOPING WEDNESDAY AFTERNOON IN ASSOCIATION WITH THE FINAL PASSING SHORTWAVE. FOR NOW WILL LEAVE POPS IN THE SLIGHT CHANCE CATEGORY AS MODEL SOUNDING ARE QUITE DRY AND MODEL GUIDANCE HAS TRENDED DRIER. EXPECT LOWS WEDNESDAY MORNING WILL GENERALLY BE IN THE 40S... WITH HIGHS WEDNESDAY AFTERNOON IN THE 60S. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 315 AM TUESDAY... WEDNESDAY NIGHT AND THURSDAY... A S/W RIDGE IN THE MID-UPPER LEVELS AND ITS ATTENDANT SFC HIGH WILL CROSS CENTRAL NC WEDNESDAY NIGHT INTO THURSDAY. THIS WEATHER SYSTEM WILL PROVIDE PLENTY OF DRY STABLE AIR LEADING TO CLEAR SKIES WEDNESDAY NIGHT AND INTO THURSDAY. SFC WINDS WILL DECOUPLE EARLY WEDNESDAY EVENING...ALLOWING TEMPS TO COOL QUICKLY. LATEST MOS GUIDANCE HAS COME IN A COUPLE OF DEGREES WARMER THAN PREVIOUS RUN. NOT READY TO BUY INTO THIS YET AS SFC DEWPOINTS UNDERNEATH THE HIGH AT THIS TIME ARE IN THE 20S TO LOWER 30S. WENT WITH MIN TEMPS UPPER 30S NORTH-NW TO LOWER 40S SOUTH. POTENTIAL FOR LIGHT FROST DOES NOT LOOK AS GOOD AS IT DID 24-48 HOURS AGO. HOWEVER STILL BELIEVE THAT A SPOT OR TWO ACROSS THE NORTHERN PIEDMONT MAY DIP BRIEFLY INTO THE MID 30S TO ALLOW FROST FORMATION BUT LIMITED NATURE OF THE LIGHT FROST SUGGEST THAT AN ADVISORY WOULD PROBABLY BE OVERKILL. SFC HIGH WILL SCOOT QUICKLY EAST THURSDAY WITH A WARM BREEZY SW SFC WIND DEVELOPING IN ITS WAKE. THIS LOW LEVEL FLOW WILL ADVECT WARMER AIR INTO CENTRAL NC. AGAIN...MOS GUIDANCE HAS TRENDED WARMER COMPARED TO PREVIOUS RUNS. PREFER TO WAIT TO SEE IF THIS TREND HOLDS AS MODEL LOW LEVEL THICKNESSES SUPPORT MAX TEMPS 3-5 DEGREES COOLER. FOR NOW WILL FAVOR MAX TEMPS ON THE COOL END OF MOS GUIDANCE... VARYING FROM NEAR 70 ACROSS THE NORTH TO THE LOWER 70S SOUTH. THURSDAY NIGHT AND FRIDAY...WARM AND DRY CONDITIONS WILL PERSIST AS FLOW ALOFT WILL REMAIN ZONAL AND LOW LEVEL SW FLOW CONTINUES WITH A SFC HIGH ANCHORED OFF THE SE U.S. COAST. THE MODIFYING AIR MASS WILL SUPPORT MIN TEMPS THURSDAY NIGHT ABOUT 10 DEGREES WARMER THAN THE PREVIOUS NIGHT (UPPER 40S TO AROUND 50). MAX TEMPS FRIDAY AFTERNOON REBOUND WELL INTO THE 70S...APPROACHING 80 IN THE FAR SOUTH-SE. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 315 AM TUESDAY... FRIDAY NIGHT AND SATURDAY...A S/W IN THE NORTHERN STREAM WILL CROSS THE GREAT LAKES AND NEW ENGLAND. THIS FEATURE WILL DRAG A SFC COLD FRONT TOWARD CENTRAL NC BY LATE FRIDAY AND FRIDAY NIGHT...CROSSING INTO OUR REGION EARLY SATURDAY BEFORE DISSIPATING. BEST/DEEPEST MOISTURE AND BETTER LIFT WILL OCCUR WELL TO OUR NORTH-NORTHWEST. THE FRONT LOSES A LOT OF ITS UPPER SUPPORT BY THE TIME IT REACHES CENTRAL NC LATE FRIDAY NIGHT INTO EARLY SATURDAY. IN ADDITION...MOISTURE WILL BE FAIRLY LIMITED. PLAN TO MAINTAIN A SLIGHT CHANCE POP ACROSS THE FAR NORTH FRIDAY NIGHT AND A SLIGHT CHANCE POP MOST PLACES SATURDAY THOUGH IT APPEARS THAT S/W RIDGING ALOFT WILL TAKE HOLD BY SATURDAY AFTERNOON. SUBSIDENCE ASSOCIATED WITH THIS FEATURE SHOULD LIMIT SHOWER DEVELOPMENT. ADDITIONAL CLOUD COVER FRIDAY NIGHT AND A LIGHT SOUTH WIND WILL RESULT IN MILD OVERNIGHT CONDITIONS. A MIX OF CLOUDS AND SUN SATURDAY AND VERY LITTLE CHANGE IN THE AIR MASS SUPPORTS MAX TEMPS IN THE MID-UPPER 70S. SUNDAY INTO MONDAY...UPPER LEVEL FLOW WILL GRADUALLY BACK TO THE SW IN ADVANCE OF A DEVELOPING/STRENGTHENING L/W TROUGH THAT WILL APPROACH FROM THE WEST. A S/W RIDGE OVER SE U.S. SUNDAY WILL MAINTAIN WARM AND MOSTLY DRY CONDITIONS. CANNOT RULE OUT AN ISOLATED SHOWER LATE SUNDAY AFTERNOON AS NEAR SFC FLOW BECOMES SELY...LEADING TO A WEAK UPSLOPE COMPONENT AND SOME MOISTURE ADVECTION OFF THE ATLANTIC. SHOWER THREAT APPEARS TOO MINIMAL TO MENTION IN FORECAST AT THIS TIME. SHOWER THREAT WILL GRADUALLY INCREASE MONDAY AS DEEP/STRENGTHENING SLY FLOW WILL ADVECT GULF MOISTURE INTO CENTRAL NC. THIS MOIST AND SLIGHTLY UNSTABLE AIR MASS MAY SUPPORT A FEW SHOWERS BY MONDAY AFTERNOON DUE TO SFC HEATING. BETTER DYNAMICS/SUPPORT ALOFT WILL OCCUR MONDAY NIGHT INTO TUESDAY FOR A GREATER THREAT FOR SHOWERS. TEMPS SUNDAY AND MONDAY EXPECTED TO REMAIN MILD WITH MAX TEMPS AVERAGING 5-6 DEGREES ABOVE NORMAL. EXPECT MIN TEMPS IN THE 50S WITH AFTERNOON TEMPS IN THE 75-80 DEGREE RANGE. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 755 AM TUESDAY... 24 HOUR TAF PERIOD: A COLD FRONT WILL MOVE THROUGH THE AREA THIS MORNING. ONCE THE FRONT PASSES A GIVEN LOCATION EXPECT CIGS SHOULD LIFT TO VFR WHEN IN A FEW HOURS. THIS HAS ALREADY OCCURRED AT KGSO AND KINT. THE FRONT IS EXPECTED TO MOVE THROUGH KRDU IN THE 13-15Z TIMEFRAME... THEN KFAY AND KRWI IN THE 15-18Z TIMEFRAME. CANT COMPLETELY RULE OUT A FEW SHOWERS THIS MORNING AT KFAY AND KRWI THROUGH AROUND 15Z. HOWEVER...ANY SHOWERS SHOULD BE BRIEF AND FAIRLY LIGHT. EXPECT VFR CONDITIONS TO RETURN TO KRDU BY AROUND MID MORNING TODAY. WE MAY SEE SOME OF THE LOWER LEVEL MOISTURE LINGERING AT KFAY AND KRWI AS A LINGERING SURFACE TROUGH IS EXPECTED TO STALL ACROSS OUR FAR EASTERN/SOUTHEASTERN REACHES OF CENTRAL NC. THUS... WILL NOT SHOW CONDITIONS BECOMING VFR AT KFAY AND KRWI UNTIL 18Z (AND COULD EVEN LINGER AS LATE AS 21Z). OTHERWISE... EXPECT WINDS WILL SWING AROUND TO MORE OF A WNW TO NW DIRECTION BEHIND THE FRONT... WITH WINDS BECOMING NORTHERLY TONIGHT. VFR CONDITIONS AREA EXPECTED TONIGHT. HOWEVER... SKIES AREA EXPECTED TO BE PARTLY TO AT TIME MOSTLY CLOUDY (VFR CIGS THOUGH) AS AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION. OUTLOOK: AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA WEDNESDAY... WITH POSSIBLY SOME VERY LIGHT SHOWERS. HOWEVER... AT THIS TIME VFR CONDITIONS ARE EXPECTED ON WEDNESDAY AS MODELS HAVE TRENDED A BIT DRIER. OTHERWISE... MAINLY VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE PERIOD. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...BLAES/BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...BSD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
757 AM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL MOVE EAST ACROSS THE AREA THIS MORNING. SURFACE HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT THROUGH WEDNESDAY NIGHT. MEANWHILE AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE ACROSS THE AREA ON WEDNESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 255 AM TUESDAY... TODAY: THE SURFACE COLD FRONT THIS MORNING IS CURRENTLY MOVING ACROSS THE MOUNTAINS OF NC. EXPECT THE SURFACE FRONT WILL CONTINUE TO SLOWLY SHIFT EASTWARD ACROSS CENTRAL THIS MORNING...AS THE FULL LATITUDE TROUGH ALOFT TO OUR WEST CONTINUES TO SHIFT EASTWARD. EXPECT THE MAIN SURFACE FRONT SHOULD BE TO THE EAST OF CENTRAL NC BY EARLY AFTERNOON AT THE LATEST. HOWEVER... WITH THE DEEP MOIST SOUTHWESTERLY MID/UPPER LEVEL FLOW AND PW`S STILL AROUND 1.5+ INCHES THIS MORNING ACROSS OUR EAST EXPECT WE WILL SEE SOME SHOWERS AND PERHAPS OF AN ISOLATED RUMBLE OF THUNDER FOR LOCATIONS IN THE SANDHILLS AND COASTAL PLAIN. 0-6KM DEEP LAYER SHEAR IS IMPRESSIVE THIS MORNING IN THE 60 TO 80 KT RANGE ACROSS THE CWA. HOWEVER... GIVEN THE TIME OF MORNING AND RAINFALL FROM EARLIER TODAY WE REMAIN RATHER STABLE AT THE SURFACE. THUS.. VERY LITTLE IF ANY SURFACE INSTABILITY TO WORK WITH WE ARE NOT EXPECTED MUCH OF A SEVERE THREAT. HOWEVER... THE LATEST RAP DID SHOW MAYBE A 100 J/KG OF MLCAPE DEVELOPING LATER THIS MORNING AS THE SURFACE FRONT APPROACHES POINTS GENERALLY ALONG AN EAST OF RALEIGH. THUS... WE CANT RULE OUT A STRONG WIND GUST OR TWO ACROSS EASTERN PORTIONS OF THE AREA... BUT THE THREAT WILL REMAIN QUITE SMALL AT BEST. WITH THE DEEP TROUGH ALOFT EXPECTED TO REMAIN TO THE WEST OF THE AREA TODAY... WE SHOULD SEE A GOOD BIT OF MID AND HIGH LEVEL MOISTURE TO START THE DAY EVEN AFTER THE SURFACE FRONT PUSHES TO THE EAST. IN FACT WE MAY EVEN SEE SOME LINGER LOW LEVEL MOISTURE ACROSS OUR FAR EAST/SOUTHEAST REACHES OF THE CWA BEHIND THE FRONT TODAY IN ASSOCIATED WITH A LINGERING SURFACE TROUGH. WHILE WE DO NOT EXPECT ANY PRECIP AFTER 18Z OR SO ACROSS OUR EAST/SOUTHEAST (OR ANYWHERE IN THE CWA)... WE MAY SEE MOSTLY CLOUDY SKIES LINGERING INTO LATE IN THE DAY... WITH LOCATIONS ACROSS THE WESTERN PIEDMONT PERHAPS SEE THE MOST SUN TODAY. WRT HIGH TEMPS.... STILL THINK WE WILL SEE HIGH TEMPS RANGE FROM THE MID 60S NW TO THE LOWER 70S SOUTH AND EAST... AS WE WILL HAVE HAVE A DOWNSLOPE FLOW... PLUS THICKNESS VALUES ARE NOT EXPECTED TO CRASH. TONIGHT AND WEDNESDAY: EXPECT A SERIES OF EMBEDDED S/W`S IN THE DEEP TROUGH ALOFT WILL CROSS THE REGION AS THE DEEP TROUGH ITSELF SHIFTS EASTWARD AND ACROSS THE AREA THROUGH WEDNESDAY. THIS WILL RESULT IN PERIODS OF PARTLY TO MOSTLY CLOUDY/CLOUDY SKIES. EXPECT WE WILL GENERALLY REMAIN DRY THOUGH. HOWEVER... WITH 500 MB HEIGHTS FALLING SOME 150 METERS BETWEEN NOW AND WEDNESDAY MORNING WE WILL SEE OUR INSTABILITY ALOFT INCREASE... WITH POSSIBLY SOME SHOWERS DEVELOPING WEDNESDAY AFTERNOON IN ASSOCIATION WITH THE FINAL PASSING SHORTWAVE. FOR NOW WILL LEAVE POPS IN THE SLIGHT CHANCE CATEGORY AS MODEL SOUNDING ARE QUITE DRY AND MODEL GUIDANCE HAS TRENDED DRIER. EXPECT LOWS WEDNESDAY MORNING WILL GENERALLY BE IN THE 40S... WITH HIGHS WEDNESDAY AFTERNOON IN THE 60S. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 315 AM TUESDAY... WEDNESDAY NIGHT AND THURSDAY... A S/W RIDGE IN THE MID-UPPER LEVELS AND ITS ATTENDANT SFC HIGH WILL CROSS CENTRAL NC WEDNESDAY NIGHT INTO THURSDAY. THIS WEATHER SYSTEM WILL PROVIDE PLENTY OF DRY STABLE AIR LEADING TO CLEAR SKIES WEDNESDAY NIGHT AND INTO THURSDAY. SFC WINDS WILL DECOUPLE EARLY WEDNESDAY EVENING...ALLOWING TEMPS TO COOL QUICKLY. LATEST MOS GUIDANCE HAS COME IN A COUPLE OF DEGREES WARMER THAN PREVIOUS RUN. NOT READY TO BUY INTO THIS YET AS SFC DEWPOINTS UNDERNEATH THE HIGH AT THIS TIME ARE IN THE 20S TO LOWER 30S. WENT WITH MIN TEMPS UPPER 30S NORTH-NW TO LOWER 40S SOUTH. POTENTIAL FOR LIGHT FROST DOES NOT LOOK AS GOOD AS IT DID 24-48 HOURS AGO. HOWEVER STILL BELIEVE THAT A SPOT OR TWO ACROSS THE NORTHERN PIEDMONT MAY DIP BRIEFLY INTO THE MID 30S TO ALLOW FROST FORMATION BUT LIMITED NATURE OF THE LIGHT FROST SUGGEST THAT AN ADVISORY WOULD PROBABLY BE OVERKILL. SFC HIGH WILL SCOOT QUICKLY EAST THURSDAY WITH A WARM BREEZY SW SFC WIND DEVELOPING IN ITS WAKE. THIS LOW LEVEL FLOW WILL ADVECT WARMER AIR INTO CENTRAL NC. AGAIN...MOS GUIDANCE HAS TRENDED WARMER COMPARED TO PREVIOUS RUNS. PREFER TO WAIT TO SEE IF THIS TREND HOLDS AS MODEL LOW LEVEL THICKNESSES SUPPORT MAX TEMPS 3-5 DEGREES COOLER. FOR NOW WILL FAVOR MAX TEMPS ON THE COOL END OF MOS GUIDANCE... VARYING FROM NEAR 70 ACROSS THE NORTH TO THE LOWER 70S SOUTH. THURSDAY NIGHT AND FRIDAY...WARM AND DRY CONDITIONS WILL PERSIST AS FLOW ALOFT WILL REMAIN ZONAL AND LOW LEVEL SW FLOW CONTINUES WITH A SFC HIGH ANCHORED OFF THE SE U.S. COAST. THE MODIFYING AIR MASS WILL SUPPORT MIN TEMPS THURSDAY NIGHT ABOUT 10 DEGREES WARMER THAN THE PREVIOUS NIGHT (UPPER 40S TO AROUND 50). MAX TEMPS FRIDAY AFTERNOON REBOUND WELL INTO THE 70S...APPROACHING 80 IN THE FAR SOUTH-SE. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 315 AM TUESDAY... FRIDAY NIGHT AND SATURDAY...A S/W IN THE NORTHERN STREAM WILL CROSS THE GREAT LAKES AND NEW ENGLAND. THIS FEATURE WILL DRAG A SFC COLD FRONT TOWARD CENTRAL NC BY LATE FRIDAY AND FRIDAY NIGHT...CROSSING INTO OUR REGION EARLY SATURDAY BEFORE DISSIPATING. BEST/DEEPEST MOISTURE AND BETTER LIFT WILL OCCUR WELL TO OUR NORTH-NORTHWEST. THE FRONT LOSES A LOT OF ITS UPPER SUPPORT BY THE TIME IT REACHES CENTRAL NC LATE FRIDAY NIGHT INTO EARLY SATURDAY. IN ADDITION...MOISTURE WILL BE FAIRLY LIMITED. PLAN TO MAINTAIN A SLIGHT CHANCE POP ACROSS THE FAR NORTH FRIDAY NIGHT AND A SLIGHT CHANCE POP MOST PLACES SATURDAY THOUGH IT APPEARS THAT S/W RIDGING ALOFT WILL TAKE HOLD BY SATURDAY AFTERNOON. SUBSIDENCE ASSOCIATED WITH THIS FEATURE SHOULD LIMIT SHOWER DEVELOPMENT. ADDITIONAL CLOUD COVER FRIDAY NIGHT AND A LIGHT SOUTH WIND WILL RESULT IN MILD OVERNIGHT CONDITIONS. A MIX OF CLOUDS AND SUN SATURDAY AND VERY LITTLE CHANGE IN THE AIR MASS SUPPORTS MAX TEMPS IN THE MID-UPPER 70S. SUNDAY INTO MONDAY...UPPER LEVEL FLOW WILL GRADUALLY BACK TO THE SW IN ADVANCE OF A DEVELOPING/STRENGTHENING L/W TROUGH THAT WILL APPROACH FROM THE WEST. A S/W RIDGE OVER SE U.S. SUNDAY WILL MAINTAIN WARM AND MOSTLY DRY CONDITIONS. CANNOT RULE OUT AN ISOLATED SHOWER LATE SUNDAY AFTERNOON AS NEAR SFC FLOW BECOMES SELY...LEADING TO A WEAK UPSLOPE COMPONENT AND SOME MOISTURE ADVECTION OFF THE ATLANTIC. SHOWER THREAT APPEARS TOO MINIMAL TO MENTION IN FORECAST AT THIS TIME. SHOWER THREAT WILL GRADUALLY INCREASE MONDAY AS DEEP/STRENGTHENING SLY FLOW WILL ADVECT GULF MOISTURE INTO CENTRAL NC. THIS MOIST AND SLIGHTLY UNSTABLE AIR MASS MAY SUPPORT A FEW SHOWERS BY MONDAY AFTERNOON DUE TO SFC HEATING. BETTER DYNAMICS/SUPPORT ALOFT WILL OCCUR MONDAY NIGHT INTO TUESDAY FOR A GREATER THREAT FOR SHOWERS. TEMPS SUNDAY AND MONDAY EXPECTED TO REMAIN MILD WITH MAX TEMPS AVERAGING 5-6 DEGREES ABOVE NORMAL. EXPECT MIN TEMPS IN THE 50S WITH AFTERNOON TEMPS IN THE 75-80 DEGREE RANGE. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 755 AM TUESDAY... 24 HOUR TAF PERIOD: A COLD FRONT WILL MOVE THROUGH THE AREA THIS MORNING. ONCE THE FRONT PASSES A GIVEN LOCATION EXPECT CIGS SHOULD LIFT TO VFR WHEN IN A FEW HOURS. THIS HAS ALREADY OCCURRED AT KGSO AND KINT. THE FRONT IS EXPECTED TO MOVE THROUGH KRDU IN THE 13-15Z TIMEFRAME... THEN KFAY AND KRWI IN THE 15-18Z TIMEFRAME. CANT COMPLETELY RULE OUT A FEW SHOWERS THIS MORNING AT KFAY AND KRWI THROUGH AROUND 15Z. HOWEVER...ANY SHOWERS SHOULD BE BRIEF AND FAIRLY LIGHT. EXPECT VFR CONDITIONS TO RETURN TO KRDU BY AROUND MID MORNING TODAY. WE MAY SEE SOME OF THE LOWER LEVEL MOISTURE LINGERING AT KFAY AND KRWI AS A LINGERING SURFACE TROUGH IS EXPECTED TO STALL ACROSS OUR FAR EASTERN/SOUTHEASTERN REACHES OF CENTRAL NC. THUS... WILL NOT SHOW CONDITIONS BECOMING VFR AT KFAY AND KRWI UNTIL 18Z (AND COULD EVEN LINGER AS LATE AS 21Z). OTHERWISE... EXPECT WINDS WILL SWING AROUND TO MORE OF A WNW TO NW DIRECTION BEHIND THE FRONT... WITH WINDS BECOMING NORTHERLY TONIGHT. VFR CONDITIONS AREA EXPECTED TONIGHT. HOWEVER... SKIES AREA EXPECTED TO BE PARTLY TO AT TIME MOSTLY CLOUDY (VFR CIGS THOUGH) AS AN UPPER LEVEL DISTURBANCE MOVES ACROSS THE REGION. OUTLOOK: AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE AREA WEDNESDAY... WITH POSSIBLY SOME VERY LIGHT SHOWERS. HOWEVER... AT THIS TIME VFR CONDITIONS ARE EXPECTED ON WEDNESDAY AS MODELS HAVE TRENDED A BIT DRIER. OTHERWISE... MAINLY VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER OF THE PERIOD. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BSD/KCP NEAR TERM...BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...BSD
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1014 AM CDT TUE APR 8 2014 .DISCUSSION...UPDATED FOR LATEST MARINE AND FIRE WEATHER DISCUSSION BELOW. && .MARINE...MIXING OF NORTHWEST FLOW TO THE SURFACE GETTING UNDERWAY THIS MORNING BUT WINDS HOLDING IN THE 12-15 KNOT RANGE WITH FEW HIGHER GUSTS OVER THE OFFSHORE WATERS. WITH LIMITED COLD ADVECTION EVEN THOUGH 850 MB WINDS SIT ON 30-33 KNOTS AND SHOULD BE ABLE TO MIX DOWN A BIT. MOST RECENT NAM DATA IN THE 950-925 MB LAYER INDICATE 20-22 KNOTS WITH LESS TOWARD THE SURFACE...AND IT MAY BE A BIT TOUGH TO REALIZE 20 KNOT SUSTAINED ACROSS THE OFFSHORE WATERS...ESPECIALLY THE SOUTHERN LEG WHICH IS FARTHER AWAY FROM THE BETTER PRESSURE GRADIENT. FOR NOW...WILL HOLD ADVISORY/CAUTION AS IS AND MONITOR FOR POSSIBLE CANCELLATION EARLY THIS AFTERNOON. 52/BSG && .FIRE WEATHER...LATEST 12Z NAM AND 12Z HRRR ARE RIGHT IN TUNE WITH THE CURRENT THINKING ON 20 FOOT WINDS...WITH A LATE MORNING/EARLY AFTERNOON SURGE ACROSS THE UPPER VALLEY AND RIO GRANDE PLAINS DIMINISHING BELOW 15 MPH AS THE LOWEST RH APPROACHES. IN THE WARNING AREA...THE 15+ MPH 20 FOOT NORTHWEST WINDS LINE UP WITH THE SHARPEST DEW POINT DROP BETWEEN 1 AND 5 PM. THE BIG QUESTION WILL BE HOW LOW THE HUMIDITY FALLS...WE NEED TO DROP JUST BELOW 15 PERCENT FOR A COUPLE HOURS TO REALIZE THE `FLASH DROUGHT` SITUATION THAT CAN CAUSE RAPID WILDFIRE GROWTH AND THAT MAY BE A STRETCH BUT SITUATION IS RIGHT ON THE FENCE SO NO REASON TO REMOVE THE SAFETY VALVE OF THE WARNING FOR NOW. 52/BSG && .PREV DISCUSSION... /ISSUED 628 AM CDT TUE APR 8 2014/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...VFR CONDITIONS WITH CLEAR SKIES EXPECTED TODAY AS NORTHWESTERLY WINDS USHER IN MUCH DRIER AIR. WINDS WILL GUST AT 18 TO 25 KNOTS THROUGH THE LATE MORNING AND AFTERNOON. WIND SPEEDS WILL DECREASE AFTER SUNSET AND VFR CONDITIONS ARE EXPECTED TO HOLD OVERNIGHT. PREV DISCUSSION... /ISSUED 355 AM CDT TUE APR 8 2014/ SHORT TERM /NOW THROUGH WEDNESDAY/...UPPER LEVEL TROUGH AXIS IS CLEAR ON WATER VAPOR JUST TO THE NORTHWEST OF THE REGION. MOST EVIDENT AREAS OF LARGE SCALE LIFT ARE NOW EAST OF DEEP SOUTH TEXAS WITH THE RADAR BECOMING INCREASINGLY QUIET OVER THE LAST FEW HOURS. LOW LEVEL MOISTURE PERSISTS...ESPECIALLY NEAR THE COAST... AND PATCHES OF FOG MAY DEVELOP EARLY THIS MORNING IN CAMERON AND WILLACY COUNTY. TODAY...AS THE UPPER LEVEL TROUGH AXIS CLEARS TO THE EAST A REINFORCING SHOT OF NORTHWESTERLY SURFACE WINDS WILL MOVE INTO THE AREA. NAM12 AND ARW/NMM 00Z GUIDANCE PRODUCES WIND SPEEDS AROUND 15 TO 20 MPH THROUGH THE DAY WITH DEW POINTS DROPPING INTO THE LOW 30S ACROSS MOST OF THE AREA. MET AND MAV MOS DO NOT SHOW DEW POINTS THIS LOW...BUT SUSPECT THE CLIMATOLOGY SIGNAL IS TOO STRONG IN THE DATASET FOR THE ANOMALOUSLY DRY AIR AND WENT CLOSER TO THE RAW MODEL OUTPUT BASED ON THE SOURCE AIR MASS IN SOUTHEASTERN COLORADO AND NEW MEXICO WITH DEW POINTS AROUND 0 TO 10 DEGREES F IN THAT AREA. DEW POINTS WILL DROP QUICKLY A FEW HOURS AFTER SUNRISE WITH VERTICAL MIXING COMBINING WITH ADVECTION OF VERY DRY AIR. THERE WILL BE VERY WEAK NET COLD ADVECTION ONGOING BUT WITH AMPLE SUNSHINE AND INCREASING 850/700MB THICKNESS VALUES...CONTINUED A LITTLE WARMER THAN GUIDANCE ON FORECAST MAXES. PRESSURE GRADIENT SHOULD BE STRONG ENOUGH FOR 20 KNOT MARINE WINDS AND NAM/HIGH RES DEPICTION OF LOWER WINDS NEAR SHORE AND ADVISORY LEVEL WINDS OFFSHORE MAKES SENSE GIVEN SATELLITE DERIVED AND OBSERVED SEA SURFACE TEMPERATURE OBS. HAVE ISSUED A SMALL CRAFT ADVISORY FOR THE OFFSHORE ZONES AND A RED FLAG WARNING FOR ALL BUT ZAPATA AND JIM HOGG COUNTIES FOR SEVERAL HOURS OF 15 MPH 20 FOOT WIND AND AT OR BELOW 15 PERCENT RELATIVE HUMIDITY. WIND SPEEDS ARE FORECAST TO BE A LITTLE TOO LOW IN JIM HOGG AND ZAPATA COUNTY FOR A WARNING WITH THIS FORECAST PACKAGE. TONIGHT...BOUNDARY LAYER IS EXPECTED TO FULLY DECOUPLE TONIGHT AMID MOSTLY CLEAR SKIES. WINDS OFFSHORE WILL SHIFT TO THE EAST. VERY DRY NEAR SURFACE AIR AND GOOD RADIATIONAL COOLING CONDITIONS WILL LIKELY PRODUCE LOWS IN THE LOW TO MID 50S. WEDNESDAY...EASTERLY LOW LEVEL FLOW WILL BECOME MORE SOUTHEASTERLY WEDNESDAY MORNING INTO THE AFTERNOON AS SURFACE HIGH PRESSURE STRENGTHENS OVER THE NORTH CENTRAL GULF OF MEXICO. A SLOW RETURN OF LOW LEVEL MOISTURE WILL ALSO OCCUR WITH THOSE WINDS ALTHOUGH IT WILL PROBABLY TAKE A DAY OR TWO TO RECHARGE THE WESTERN GULF AIR MASS AFTER THE ONSLAUGHT OF VERY DRY CONTINENTAL AIR EXPECTED ON TUESDAY. WITH THAT...PLEASANT WEATHER IS EXPECTED ON WEDNESDAY WITH WARM TEMPERATURES IN THE MID TO UPPER 80S AND A STEADY BUT NOT OVER WHELMING SOUTHEAST BREEZE. LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...A BROAD MID LEVEL RIDGE WILL RESIDE OVER THE SOUTHWEST UNITED STATES AND WILL MAINTAIN A PERIOD OF RELATIVELY QUIET WEATHER THROUGH THE END OF THE WEEK AND EARLY PART OF THE WEEKEND. LOW RELATIVE HUMIDITY VALUES WILL REPEAT THURSDAY AFTN...DIPPING INTO THE 20S OUT WEST AND ENHANCING FIRE WEATHER CONCERNS A BIT. LOW TEMPS WEDNESDAY NIGHT WILL DIP INTO THE 50S...WHILE HIGH TEMPS THURSDAY WILL BE IN THE 80S...UNDER CLEAR SKIES. LATE IN THE WEEK...WITH HIGH PRESSURE BUILDING IN OVER THE NORTH GULF...AND SOUTHEAST WINDS BECOMING MORE ESTABLISHED...CLOUD COVER WILL INCREASE BACK INTO THE PARTLY CLOUDY TO CLOUDY RANGE...WITH TEMPERATURES TRENDING TOWARD ABOVE NORMAL. MID LEVEL RIDGING WILL STILL DOMINATE JUST UPSTREAM...BUT A TROUGH WILL MOVE INTO THE LWR WEST COAST...AND THE AMPLIFIED PATTERN WILL FLATTEN. FRIDAY NIGHT INTO SATURDAY...INCREASING MOISTURE WILL SUPPORT A SLIGHT CHANCE OF SHOWERS AS MID LEVEL DIFFLUENCE FROM THE UPSTREAM TROUGH/LOW OVER THE SOUTHERN SOUTHWEST HELPS DESTABILIZE THINGS A BIT OVER DEEP SOUTH TEXAS AND THE RGV FRIDAY INTO SATURDAY. THE POTENTIAL FOR THE ARRIVAL OF A STRONGER FRONT WILL INCREASE SUNDAY NIGHT INTO MONDAY ACCORDING TO THE GFS AND ECMWF...AS THE EASTWARD MOVING TROUGH COINCIDES WITH A COLD FRONT MOVING SOUTH ACROSS THE REGION. THE GFS BRINGS A GOO AMOUNT OF RAIN THE THE CWA LATE SUNDAY NIGHT...WHILE THE ECMWF IS SLOWER AND KEEPS MOST OF THE RAIN NORTH OF THE CWA BUT BRINGS A SECONDARY FRONT THROUGH THE RGV MONDAY AFTERNOON TO EVENING. CHOSE TO GO WITH A BLEND...SINCE TIMING ISSUES WERE NOT EXTREME... AND WENT WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY AND MONDAY NIGHT. THIS IS STILL AT THE TAIL END OF THE FORECAST... AND THERE IS A FAIR AMOUNT OF UNCERTAINTY WITH THE AMOUNT OF RAIN THAT MIGHT MATERIALIZE...BUT BOTH MODELS AGREE WITH A CANADIAN COLD FRONT COINCIDING WITH A SOUTHERN STREAM DISTURBANCE MOVING OVER AND AN AMPLIFIED MID LEVEL PATTERN WITH RIDGING OVER THE WEST AND A PHASING TROUGHING OVER THE NORTHERN PLAINS TO UPPER MIDWEST ON MONDAY. CONDITIONS WILL CLEAR OUT RAPIDLY POST FRONT WITH AN AMPLIFIED MID LEVEL RIDGE BUILDING IN QUICKLY AFTER THE FRONT. TEMPERATURES WILL DIP A HANDFUL OF DEGREES IN THE WAKE OF THE FRONT AS SKIES CLEAR. MARINE... NOW THROUGH WEDNESDAY...A SURGE OF NORTHWESTERLY WINDS IS EXPECTED TO ARRIVE LATER THIS MORNING AND EARLY THIS AFTERNOON. SMALL CRAFT SHOULD EXERCISE CAUTION ON THE LAGUNA MADRE AND NEARSHORE WATERS AND A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE OFFSHORE WATERS FROM MID MORNING THROUGH THIS EVENING DUE TO STRONG NORTHWEST WINDS. SEAS WILL BE MODERATE NEARSHORE AND LIKELY AT LEAST BRIEFLY BECOME ROUGH OFFSHORE. BETTER CONDITIONS ARE EXPECTED LATE TUESDAY NIGHT INTO WEDNESDAY AS WIND SPEEDS DECREASE AND SHIFT TO THE EAST AND EVENTUALLY SOUTHEAST. SEAS ARE EXPECTED TO REMAIN MODERATE THROUGH WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...BROAD HIGH PRESSURE OVER THE NORTHWEST GULF WILL INITIALIZE THE LONG TERM FORECAST WITH LIGHT TO MODERATE SOUTHEAST WINDS AND LOW SEAS. THEREAFTER THOUGH...THROUGH SATURDAY...SOUTHEAST WINDS WILL PUSH 20 KNOTS AND SEAS WILL INCREASE TO 5 TO 7 FEET OFFSHORE AS LOWER PRESSURE OVER THE SOUTHERN PLAINS INTERACTS WITH GULF HIGH PRESSURE TO GENERATE SOMEWHAT STRONGER WINDS. RAIN CHANCES WILL BE LOW TO NEARLY NONEXISTENT. FIRE WEATHER... ELEVATED AND CRITICAL FIRE DANGER IS FORECAST ACROSS THE RIO GRANDE VALLEY AND DEEP SOUTH TEXAS TODAY. A SURGE OF NORTHWEST WINDS WILL USHER IN MUCH DRIER AIR LATE THIS MORNING AND THIS AFTERNOON. RELATIVE HUMIDITY VALUES WILL FALL TO AROUND 12 TO 18 PERCENT WITH 20 FOOT WIND SPEEDS AROUND 15 MPH. A RED FLAG WARNING HAS BEEN ISSUED FOR STARR...BROOKS...KENEDY...AND INLAND CAMERON AND WILLACY COUNTIES TODAY AND ENHANCED FIRE DANGER CONDITIONS WILL EXIST ACROSS THE REMAINDER OF THE AREA. WIND SPEEDS ARE EXPECTED TO BE LOWER ON WEDNESDAY WITH RELATIVE HUMIDITY VALUES INCREASING. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...RED FLAG WARNING UNTIL 6 PM CDT THIS EVENING FOR TXZ250>255. GM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT WEDNESDAY FOR GMZ170-175. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
111 PM CDT TUE APR 8 2014 .DISCUSSION... 1106 AM CDT MORNING UPDATE... HAVE MADE SOME MINOR ADJUSTMENTS TO POPS THIS AFTERNOON. LAKE BREEZE DEVELOPMENT HAS ALREADY OCCURRED AND IT WILL PUSH INLAND ACROSS ILLINOIS AND INDIANA THROUGH THE AFTERNOON. STEEP LOW LEVEL LAPSE RATES ALREADY IN PLACE WILL FURTHER STEEPEN WITH DAYTIME HEATING AND GOOD LOW LEVEL CONVERGENCE AS LAKE BREEZE PUSHES INLAND WILL INTERACT WITH UPPER TROUGH PUSHING ACROSS THE REGION THIS AFTERNOON. THIS WILL SUPPORT SCATTERED SHOWER DEVELOPMENT INLAND OF LAKE MICHIGAN...WITH AREAS FROM THE LAKEFRONT TO 5 TO 10 MILES INLAND LIKELY REMAINING DRY EARLY THIS AFTERNOON DUE TO THE STABILIZING MARINE ENVIRONMENT AS THE LAKE BREEZE PLOWS INLAND...AND STABILIZATION OCCURRING FURTHER INLAND LATER THIS AFTERNOON. THERE IS AN OUTSIDE SHOT FOR AN ISOLATED THUNDERSTORM OR TWO GIVEN THE STEEP LOW LEVEL LAPSE RATES...HOWEVER...ITS QUESTIONABLE WHETHER THE LOW LEVEL CAPE WILL REACH HIGH ENOUGH ABOVE THE FREEZING LEVEL TO ENABLE LIGHTNING PRODUCTION. SOME OF THE HI-RES NEAR TERM GUIDANCE IS FAIRLY BULLISH ON SHOWER COVERAGE EARLY THIS AFTERNOON...SO WILL NEED TO MONITOR TRENDS FOR HIGHER COVERAGE MENTION THAN CURRENTLY FEATURED IN THE GRIDS. OTHERWISE...HAVE ADJUSTED SKY GRIDS TO ACCOUNT FOR TRENDS AND ALSO BUMPED UP INLAND TEMPERATURES A FEW DEGREES CLOSER TO 925 MB CLIMO FOR EARLY APRIL INTO THE MID AND UPPER 50S. ITS NOT OUT OF THE QUESTION THAT SOME AREAS IN NORTH CENTRAL ILLINOIS COULD APPROACH 60 DEGREES. UPDATED ZONES HAVE BEEN SENT. RC //PREV DISCUSSION... 301 AM CDT PRECIP CHANCES TODAY AND TIMING OF A COOL FRONT THURSDAY AND ASSOCIATED AFFECT ON TEMPERATURES ARE SOME OF THE CONCERNS THIS FORECAST PERIOD. EARLY MORNING WATER VAPOR IMAGERY SHOWS THE HIGH AMPLITUDE UPPER FLOW CONTINUING TO BE IN PLACE WITH A LARGE LONGWAVE TROUGH SHIFTING EAST ACROSS THE MID SECTION OF THE COUNTRY WHILE A LARGE RIDGE MOVES EAST INTO THE ROCKIES. BETWEEN THESE TWO FEATURES IS A VORT MAX THAT IS SWINGING ACROSS THE LOCAL AREA THIS MORNING BRINGING BANDS OF LIGHT RAIN WITH IT. IN ADDITION...A NARROW SHEARED TROUGH AXIS IS MOVING SOUTHEAST INTO WESTERN MINNESOTA/IOWA/MISSOURI WHICH WILL CROSS THE AREA LATER TODAY AIDING IN ADDITIONAL SHOWER CHANCES. FURTHER WEST...A CLOSED UPPER LOW IS SPINNING OFF THE CENTRAL BRITISH COLUMBIA COAST WITH A WAVE LIFTING NORTHEAST OVER THE SOUTHERN B.C COAST AHEAD OF IT. THIS ENERGY WILL DRIVE SURFACE LOW PRESSURE DEVELOPMENT ACROSS WESTERN CANADA WHICH WILL BRING THE AFOREMENTIONED COLD FRONT THURSDAY. AT THE SURFACE...LOW PRESSURE IS MOVING NORTHEAST TOWARD WESTERN NEW YORK WITH HIGH PRESSURE OVER NORTHERN MANITOBA. PRESSURE FALLS ARE BUILDING ACROSS WESTERN CANADA AS THE UPPER WAVES APPROACH. TODAY AND TONIGHT...A MIX OF CLOUDS AND SUN ARE EXPECTED TODAY THANKS TO A COMBINATION OF LAGER SCALE ASCENT PROVIDED BY THE LARGE SCALE TROUGH...STEEP LOW LEVEL LAPSE RATES WITH SOME COOLING ALOFT...AND SOME SLIGHTLY BETTER FOCUSED LIFT WITH THE SHEARED TROUGH AXIS THAT WILL CROSS LATER TODAY. THE BANDS OF LIGHT RAIN CURRENTLY ACROSS THE EASTERN THIRD TO HALF OF THE AREA WILL CONTINUE TO MOVE SOUTHEAST AND LIKELY BE CONFINED TO LAKE MICHIGAN AND NW INDIANA IN THE 12-15Z TIME FRAME BEFORE FADING OR EXITING TO THE EAST. OTHERWISE PRECIP DEVELOPMENT LOOKS TO BE MORE DIURNALLY DRIVEN AS SURFACE TEMPS WARM UP AND LAPSE RATES STEEPEN. THE NEXT FOCUSED TROUGH AXIS ARRIVES THIS AFTERNOON BUT THERE MAY BE SOME WEAKER VORT MAXIMA THAT PASS AHEAD OF IT WHICH COULD DRIVE SOME SPOTTY PRECIP ACTIVITY THROUGH THE MORNING WEST OF THE CURRENT ACTIVITY. OTHERWISE THE BEST TIME LOOKS TO BE THIS AFTERNOON AND EARLY THIS EVENING AS THE TROUGH AXIS PASSES. NORTHERLY WINDS WILL BE IN PLACE AND THE FLOW WILL BE WEAK ENOUGH TO TRIGGER A LAKE BREEZE. GIVEN THE STEEP LOW LEVEL LAPSE RATES THE LAKE BREEZE MAY PROVIDE ENOUGH LOW LEVEL CONVERGENCE TO TRIGGER SHOWERS AS WELL. WILL CONTINUE WITH MENTIONABLE POPS FOR THE ENTIRE AREA WITH THE GREATEST FOCUS ACROSS THE EASTERN HALF OR SO WHERE THE BEST COMBINATION OF UPPER TROUGH TIMING/LAPSE RATES/LAKE BREEZE COME TOGETHER. THIS INCLUDES MUCH OF THE CHICAGO METRO SOUTH TO THE KANKAKEE...PONTIAC...GIBSON CITY AREA. HIGHS WILL BE TRICKY GIVEN THE EXPECTED MIX OF SUN AND CLOUDS BUT SOME CLEARING MAY OCCUR EARLY IN THE WEST...BEFORE DIURNAL CU INCREASES...TO ALLOW TEMPS TO JUMP A BIT SO THE FORECAST COULD BE A LITTLE ON THE COOL SIDE BUT OVERALL EXPECT MID 50S WEST AND AROUND 50 EAST...WITH LOW TO MID 40S WITHIN A FEW MILES OF LAKE MICHIGAN. SOME OF THESE AREAS WITHIN 5-10 MILES OF THE LAKE MAY SEE AN EARLY HIGH THEN FALL DURING THE AFTERNOON AS THE BOUNDARY PASSES...WITH ANY SHOWER ACTIVITY ALSO AFFECTING HOURLY TEMP TRENDS. THE TROUGH AXIS WILL EXIT TO THE EAST EARLY THIS EVENING BUT SOME SHOWER ACTIVITY MAY LINGER JUST BEYOND SUNSET IN THE EAST BEFORE ENDING. HIGH PRESSURE WILL CROSS THE AREA OVERNIGHT ALLOWING FOR LIGHT WINDS AND COOLING TO AROUND 30 DEGREES FOR MOST AREAS TONIGHT. WEDNESDAY AND THURSDAY...THE UPPER FLOW WILL GO THROUGH A TRANSITION WEDNESDAY AND THURSDAY AS THE WESTERN RIDGE MOVES EAST AND DE-AMPLIFIES THANKS TO THE TROUGH OFF THE B.C. COAST MOVING INLAND AND FLATTENING IT. MID LEVEL WARMING WILL INCREASE WEDNESDAY AS H85 TEMPS JUMP TO AROUND +8C BY EVENING AND +12 TO +14C BY THURSDAY. SURFACE LOW PRESSURE WILL MOVE ACROSS SOUTHERN CANADA WITH A COLD FRONT TRAILING IT TO THE SOUTHWEST. THE PRESSURE GRADIENT BETWEEN THIS SYSTEM AND THE HIGH DEPARTING TO THE EAST WILL SUPPORT AN INCREASING SOUTHWEST WIND...WHICH WILL BECOME GUSTY WEDNESDAY NIGHT AND THURSDAY. ALL OF THIS POINTS TO A WARM UP INTO THE UPPER 50S EAST TO LOWER 60S WEST WEDNESDAY WITH THE FLOW STRONG ENOUGH TO PRECLUDE LAKE BREEZE DEVELOPMENT. TEMPS THURSDAY BECOME A BIT TOUGHER THANKS TO THE COLD FRONT CROSSING THE AREA DURING THE DAY. LATEST TRENDS BRING THE FRONT THROUGH A LITTLER SOONER...AROUND MIDDAY. THIS WILL LIMIT THE WARMING POTENTIAL FOR MUCH OF THE AREA COMPARED TO WHAT WAS SUGGESTED TO BE POSSIBLE WITH EARLIER FORECASTS. TIMING STILL SUBJECT TO CHANGE BUT WILL GO WITH HIGHS IN THE LOWER 60S NORTH TO THE UPPER 60S SOUTH. FAR SOUTHERN AREAS COULD STILL SEE 70 IF CLOUDS CAN BE THIN ENOUGH AND SOME COMPRESSIONAL WARMING CAN DEVELOP AHEAD OF THE FRONT. THE FRONT WILL BRING SOME CHANCE FOR RAIN WITH IT BUT THE BEST FORCING WILL BE FURTHER NORTH IN BETTER PROXIMITY TO UPPER FORCING. FRIDAY THROUGH THE WEEKEND...WITH THE REDUCED AMPLITUDE OF THE UPPER FLOW THE PUSH OF COOLER AIR BEHIND THE FRONT WILL NOT BE ALL THAT STRONG. THERE ARE SIGNS OF A WEAK TROUGH CROSSING THE AREA FRIDAY WHICH COULD PROVIDE SOME CLOUD COVER BUT THERE SHOULD BE ENOUGH SUN TO PUSH TEMPS INTO THE LOW TO MID 60S. HIGH PRESSURE WILL QUICKLY CROSS THE AREA SO THE FLOW MAY BE WEAK ENOUGH TO SUPPORT A LAKE BREEZE SO LAKESHORE AREAS MAY BE HELD TO THE 40S ONCE AGAIN. MEDIUM RANGE GUIDANCE CONTINUES TO SHOW SPLIT FLOW TROUGHING WORKING INTO THE WESTERN U.S. INTO SATURDAY DRIVING SURFACE LOW PRESSURE DEVELOPMENT ACROSS THE CENTRAL/NORTHERN PLAINS. THIS WILL SUPPORT A STRONGER SOUTHERLY FLOW FOR SATURDAY AND ANOTHER SURGE IN TEMPS WHICH LOOK TO BE IN THE MID AND UPPER 60S AT THIS POINT. SATURDAY LOOKS DRY AT THIS TIME BUT THE SYSTEM TO THE WEST WILL MOVE IN BRINGING RAIN CHANCES SATURDAY NIGHT. CONFIDENCE LOWERS FOR THE REST OF THE WEEKEND INTO MONDAY AS THE EVOLUTION OF THE NORTHERN AND SOUTHERN STREAM TROUGHS WILL DICTATE HOW PROGRESSIVE THE SYSTEM IS IN CROSSING THE AREA. REGARDLESS...A PERIOD OF RAIN LOOKS MORE LIKELY FROM AS EARLY AS SATURDAY NIGHT THROUGH SUNDAY AND POSSIBLY LONGER WITH THE SPEED OF DEPARTURE BEING MUCH LESS CERTAIN. A GOOD SIGNAL FOR MUCH COOLER AIR EARLY NEXT WEEK CONTINUES WHICH MAY MEAN SOME MIXED PRECIP/SNOW AS PRECIP ENDS. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * WINDS ARND 020-040 TO 10KT...WILL EVENTUALLY BECOME 040 AND SPEEDS THRU THIS EVE TO 8KT. * LAKE BREEZE PUSHING THRU WITH SOME BUILDING CLOUDS...TEMPO CIGS ARND 3KFT AGL. * WINDS RELAXING TO NW OVERNIGHT ARND 4-6KT...MAY BRIEFLY GO VRB DIR AND POTENTIALLY CALM FOR A COUPLE HRS BEFORE DAYBREAK WED. * SOUTHWEST WINDS DEVELOPING MID-MORNING WED WITH GUSTS APPROACHING 16-19KT. BEACHLER //DISCUSSION...UPDATED 18Z... LAKE BREEZE HAS DEVELOPED AND WAS SLOWLY PUSHING INLAND. EARLY THIS AFTERNOON THE BREEZE STRETCHED FROM NEAR ORD SOUTHEAST TO MDW. THIS BREEZE WILL STEADILY PUSH INLAND AND BRING NE WINDS TO ORD/MDW. THIS CONVERGENCE ZONE WILL BECOME A FOCAL POINT FOR LIFT AND BUILD THE CLOUDS. LATEST VISIBLE IMAGERY IS SHOWING THIS WITH CUMULUS DEVELOPMENT. IN ADDITION THE ENVIRONMENT IS BECOMING UNSTABLE ARND 4000-9000FT AND COULD SEE AN ISOLATED THUNDERSTORM DEVELOP JUST WEST OF ORD/MDW. IT APPEARS THAT ALL OF THE CUMULUS/PRECIP THAT DOES DEVELOP WILL BE DIURNALLY DRIVEN AND SHOULD ONLY LINGER THRU 22-23Z...THEN BY 01Z CLOUDS WILL BE CLEARING BACK OUT WITH JUST A CIRRUS DECK REMAINING. A FEW GUIDANCE MEMBERS ARE INDICATING SOME LINGERING LLVL MOISTURE...HOWEVER AT THIS TIME ONLY ENOUGH CONFIDENCE TO INCLUDE A MENTION OF FEW. THIS MAY END UP BEING ABLE TO BE PULLED THOUGH. WINDS WILL BE RELAXING BACK TO THE NORTH THEN NORTHWEST OVERNIGHT WITH SPEEDS ARND 5-8KT. WITH A VERY LIGHT GRADIENT SETTING UP OVERNIGHT...GUIDANCE IS INDICATING THAT A PERIOD OF TIME MAY SEE WINDS BECOME VRB TO CALM JUST BEFORE DAYBREAK WED. THE GRADIENT THEN PICKS UP JUST AFT DAYBREAK WITH SOUTHWEST WINDS INCREASING TO ARND 10KT AND SHUD START TO SEE GUSTS NEARING 16-19KT BY MIDDAY WED. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM CONFIDENCE IN PRECIP REMAINING WEST OF ORD...HIGH CONFIDECE IN PRECIP WEST OF MDW. * HIGH CONFIDENCE IN WINDS TURNING NORTHEAST THRU THIS EVE. * MEDIUM/HIGH CONFIDENCE IN TIMING OF WINDS TURNING BACK TO THE NORTHWEST. * LOW CONFIDENCE IN CIGS FORECAST OVERNIGHT. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...VFR. THURSDAY...CHANCE OF RAIN DURING THE DAY. BRIEF MVFR PSBL. FRIDAY...VFR. SATURDAY...CHANCE OF RAIN...VFR. SUNDAY...RAIN LIKELY WITH A CHANCE OF THUNDERSTORMS DURING THE DAY. MVFR PSBL. MONDAY...CHANCE OF RAIN. MVFR PSBL EARLY. JEE && .MARINE... 223 AM CDT LOW PRESSURE IS OVER LAKE ERIE AND IT WILL CONTINUE OFF TO THE NORTHEAST TODAY. NORTH TO NORTHWEST WINDS ARE EXPECTED THROUGH THIS EVENING. WINDS BECOME SOUTHWEST OVERNIGHT AS HIGH PRESSURE PASSES OVERHEAD AND THEN CONTINUES EASTWARD. THE NEXT LOW PASSES OVER NORTHERN ONTARIO WEDNESDAY NIGHT THROUGH THURSDAY WITH ITS COLD FRONT SWINGING THROUGH THURSDAY. SOUTH WINDS WILL INCREASE TO 30 KT AHEAD OF THE LOW WEDNESDAY...AND STILL THINKING IT WILL BE TOO STABLE FOR GALE FORCE GUSTS TO MIX DOWN TO THE SURFACE. WINDS DIMINISH TO 10 TO 20 KT AND BECOME WEST BEHIND THE COLD FRONT THURSDAY. A BROAD AREA OF HIGH PRESSURE BUILDS OVER THE LAKE LATE THIS WEEK WITH LIGHT WEST WINDS EXPECTED THROUGH FRIDAY NIGHT. THE HIGH SHIFTS EAST AND WINDS TURN SOUTH. THE GRADIENT TIGHTENS SATURDAY AHEAD OF THE NEXT LOW WITH GUSTS OF 20-25 KT EXPECTED. GUIDANCE DIFFERS WITH HOW FAST THE LOW MOVES THROUGH THIS WEEKEND SO HAVE MEDIUM CONFIDENCE IN TIMING RIGHT NOW. GUIDANCE DOES AGREE THAT WINDS TURN NORTH BEHIND THE LOW GUSTS TO AT LEAST 30 KT ARE EXPECTED LATE THIS WEEKEND INTO EARLY NEXT WEEK. SOME MODELS SHOW A BRIEF PERIOD OF LOW END GALES...CAPPED WINDS AT 30 KT FOR NOW. HEADLINES...HIGH WINDS MAY LEAD TO SMALL CRAFT CONDITIONS WEDNESDAY NIGHT THROUGH THURSDAY. THEN HIGH WINDS AND WAVES ARE POSSIBLE AGAIN LATE THIS WEEKEND INTO EARLY NEXT WEEK. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1240 PM CDT Tue Apr 8 2014 .DISCUSSION... ISSUED 900 AM CDT Tue Apr 8 2014 Mostly sunny skies currently prevail across central Illinois: however, with steep low-level lapse rates noted on 12z KILX and KDVN upper air soundings, think diurnal clouds will quickly develop later this morning into the afternoon hours. Region remains under the influence of a high-amplitude trough that has dug all the way to the Gulf Coast. Several weaker short-waves are noted within the flow, including one feature currently over southwest Iowa into eastern Kansas. This particular wave will drop southeastward and remain largely to the W/SW of Illinois today. Meanwhile, another subtle wave will drop southeastward out of Wisconsin and northeast Iowa. This feature will provide enough lift to trigger a few showers and thunderstorms across the area this afternoon. Latest HRRR seems to have a reasonable handle on the current situation, and depicts isolated to scattered convection developing by around 17/18z. Much of the convection will be focused across the E/NE KILX CWA in association with the advancing Wisconsin wave. Have updated the forecast to remove POPs and reduce sky cover this morning, then have gone with partly sunny conditions with isolated to scattered showers/thunder this afternoon. Temp forecast looks to be on track, so made no adjustments to afternoon highs in the middle to upper 50s. Zone update has already been issued. Barnes && .AVIATION... ISSUED 1240 PM CDT Tue Apr 8 2014 Diurnal CU field is currently developing across central Illinois and will become most prevalent along and east of I-57 this afternoon. Forecast soundings suggest low VFR ceilings of 3500 to 4000ft at KCMI, with lesser coverage/higher bases further west at the remaining terminals. Will include VCSH at KCMI as well, as a few showers are beginning to develop upstream over northeast Illinois. Clouds/widely scattered showers will quickly dissipate shortly after sunset, followed by clear skies overnight into Wednesday morning. Winds will initially be gusty from the northwest this afternoon, then will subside to less than 10kt by this evening. As high pressure slides across the area, winds will become W/SW by Wednesday morning. Barnes && .PREV DISCUSSION... ISSUED 304 AM CDT Tue Apr 8 2014 Low pressure exiting to the east as more northwesterly flow moves in over the Midwest this morning. Some remnant clouds and weak echoes over the forecast area on radar imagery this morning. Weak wave in the large scale trof bringing in another chance of precip. Some cold air aloft will help to add to some instability this afternoon and cannot rule out some isolated thunder chances. This is the first issue for the forecast. Warming through the week and another weak boundary and system at the end of the weekend. Not too many changes in the latter two systems. Models in good agreement through Friday...with some divergence in handling the Saturday night/Sunday storm. SHORT TERM...Today and tomorrow... Another chance for rain as a secondary wave moves into the larger scale trof aloft...with highs in the 50s. This afternoon will actually see some colder temps aloft and rather steep lapse rates in the low levels. Though the instability is weak...narrow and skinny CAPE in the forecast soundings...it is pretty deep. Cannot rule out some thunder and small hail with a relatively low freezing level. Will see the showers coming to an end this evening. Tomorrow starts a general warming trend with a southerly component working into the winds. Highs in the 60s. LONG TERM...Thursday through Monday... Forecast continues the warming trend resulting in the warmest day of the forecast on Thursday with highs approaching 70/the lower 70s. A system passing across the southern tier of Canada drags a weak frontal boundary across the Great Lakes and the Midwest...but convergence along the boundary is weak at best. Not to mention that the flow across the country is predominantly SW/NE oriented...effectively cutting off the access to deeper Gulf moisture ahead of the boundary. At this point, pops for Thursday night remain on the low side through Friday night. Far more dynamic system expected into the weekend with pops stretching from Sat night through Sunday for now as the quicker GFS/slower ECMWF having major timing differences. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
555 PM EDT TUE APR 8 2014 .UPDATE... ISSUED AT 555 PM EDT TUE APR 8 2014 MESOSCALE ANALYSIS IS SHOWING A BIT OF INSTABILITY IN OUR FAR SOUTHWESTERN COUNTIES DUE TO DECENT SFC BASED HEATING. FORECAST SOUNDINGS SHOW LAPSE RATES STEEP ENOUGH THAT WE COULD NOT RULE OUT AN ISOLD THUNDERSTORM OR TWO...ESPECIALLY CONSIDERING THE OCCASIONAL STRIKES WE CONTINUE TO PICK UP WITH THE SHOWER ACTIVITY PUSHING INTO THAT AREA OVER THE NEXT COUPLE OF HOURS. UPDATED THE ZONE PACKAGE TO INCLUDE THIS POTENTIAL THROUGH THE LATE AFTERNOON...VERY EARLY EVENING HOURS. EXPECT ANY THUNDERSTORM ACTIVITY WILL BE RESTRICTED TO AREAS WELL WEST OF INTERSTATE 75...IN PULASKI/WAYNE AND SHOULD DIE OFF WITH SUNSET AND THE LOSS OF HEATING. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 329 PM EDT TUE APR 8 2014 MID LEVEL RIDGING CURRENTLY OVER EASTERN KENTUCKY...WILL GIVE WAY TO A MID LEVEL TROUGH THIS EVENING. SCATTERED SHOWERS AND EVEN A FEW THUNDERSTORMS HAVE DEVELOPED UPSTREAM ACROSS WESTERN KENTUCKY INTO CENTRAL INDIANA. THIS ACTIVITY WILL VERY SLOWLY DRIFT SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING...REACHING THE I-75 CORRIDOR BETWEEN 7 AND 8 PM. MEANWHILE...DEWPOINTS HAVE MIXED OUT QUITE WELL ACROSS EASTERN KENTUCKY WITH A FEW PLACES GETTING CLOSE TO 25% RELATIVE HUMIDITY. THIS COULD BE A LIMITING FACTOR ON PRECIPITATION AS IT TRIES TO SPREAD INTO THE AREA THIS EVENING. HOWEVER...HRRR AND RAP BOTH SHOW SOME ACTIVITY MAKING ITS WAY ACROSS THE AREA SO WILL MAINTAIN THE LOW POPS THROUGH THE EVENING AND OVERNIGHT HOURS AS IT DRIFTS SOUTHEAST AND SLOWLY WEAKENS. NAM SEEMS OVERLY AGGRESSIVE ON GENERATING MORE SUBSTANTIAL PRECIPITATION ACROSS THE HIGHER TERRAIN TONIGHT. GIVEN VERY LITTLE SUPPORT FOR THIS AND THE AMBIENT DRY CONDITIONS IN PLACE...NOT CONFIDENT THE NAM HAS A GOOD HANDLE ON THINGS. MID LEVEL RIDGING WILL BUILD BACK ACROSS THE AREA ON WEDNESDAY WITH CLOUDS SLOWLY BREAKING UP THROUGH THE DAY. GIVEN HOW LOW DEWPOINTS HAVE GONE IN THE PAST WEEK ON DRY AFTERNOONS...OPTING TO KEEP THINGS WELL BELOW GUIDANCE...BRINGING IN SOME NEAR 25% RELATIVE HUMIDITY VALUES TOMORROW AFTERNOON. WITH CLEAR SKIES LINGERING INTO TOMORROW NIGHT...A COOLER NIGHT IS ON TAP WITH LOWS FALLING INTO THE 30S...ESPECIALLY IN THE VALLEYS...WHERE SOME FROST WILL BE A POSSIBILITY. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 427 PM EDT TUE APR 8 2014 A MORE ZONAL LONG WAVE PATTERN WILL BE IN PLACE ACROSS THE CONUS THROUGH THE FIRST HALF OF THE WEEKEND...WITH SEVERAL SHORT WAVE TROUGHS TRAVERSING THE OHIO VALLEY/GREAT LAKES REGION. AMPLIFICATION WILL THEN ENSUE FOR THE LATTER HALF OF THE WEEKEND AND INTO EARLY NEXT WEEK...AS FULL LATITUDE TROUGHING TAKES SHAPE ACROSS THE CENTRAL CONUS AND WORKS ITS WAY EAST. THERE IS DECENT MODEL AGREEMENT THROUGH THE FIRST PORTION OF THE EXTENDED...AND THEN LARGER DIFFERENCES CROP UP WITH THE EVOLUTION OF THE DEEPER AND MORE SIGNIFICANT SYSTEM TO AFFECT THE AREA BY EARLY NEXT WEEK. AS SUCH...HAVE STUCK CLOSE TO A BLEND...ALTHOUGH DID FAVOR A SLIGHTLY SLOWER TIMING OF THE HIGHER POPS ASSOCIATED WITH THE DEEPER SYSTEM...SINCE MODELS HAVE GENERALLY TRENDED THIS WAY OVER THE PAST FEW RUNS. DRY AND MILD WEATHER WILL REIGN ACROSS EASTERN KENTUCKY THROUGH THURSDAY AS HIGH PRESSURE SETTLES SOUTHEAST OF THE AREA...WITH GUSTY SOUTH TO SOUTHWEST WINDS HELPING TO BUMP TEMPERATURES UP INTO THE LOW TO MID 70S. A COLD FRONT WILL THEN SLOWLY SAG SOUTHEAST TOWARDS THE AREA LATE THURSDAY NIGHT THROUGH FRIDAY NIGHT...WITH SOME UPPER LEVEL SUPPORT AT TIMES. THERE IS SOME QUESTION AS TO HOW FAR SOUTH THE BOUNDARY WILL MAKE IT INTO OUR AREA...SO STUCK CLOSE TO THE LATEST BLEND AND THE INHERITED POPS...WITH THE OVERALL BETTER CHANCES NORTH...AND LESS TO THE SOUTH. SATURDAY THROUGH SUNDAY...BROAD RIDGING ALOFT WILL KEEP DRY WEATHER IN PLACE ACROSS THE COMMONWEALTH...WITH HIGHS RETURNING TO THE LOW TO MID 70S. DEEP TROUGHING WILL BEGIN TO INFLUENCE FROM THE WEST BY MONDAY...HOWEVER WITH THE NOTED SLOWER TREND...WILL CONTINUE TO CARRY THE HIGHEST POPS MONDAY NIGHT INTO TUESDAY MORNING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 242 PM EDT TUE APR 8 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH MUCH OF THE PERIOD AT THE TAF SITES. A MID LEVEL TROUGH WILL DROP SOUTHEAST LATE THIS EVENING...BRINGING A SOME SCATTERED SHOWERS TO PORTIONS OF EASTERN KENTUCKY. HOWEVER...THIS ACTIVITY IS NOT ANTICIPATED TO BE ALL THAT WIDESPREAD AND MAY SHOW A WEAKENING TREND AS IT DRIFTS SOUTHEAST ACROSS THE AREA. IF WE CAN GENERATE SOME RAIN AND SATURATE THINGS ENOUGH...WE COULD SEE A BRIEF PERIOD OF MVFR CIGS TONIGHT. HOWEVER...GIVEN HOW WELL DEWPOINTS HAVE COME DOWN THIS AFTERNOON...THIS MAY BE A SIGNIFICANT TASK. SO FOR NOW...GOING TO GO WITH A MORE OPTIMISTIC TAF AND KEEP THINGS VFR. IF CIGS DO LOWER TONIGHT...THEY SHOULD QUICKLY BOUNCE BACK UP EARLY TOMORROW MORNING AS DRIER AIR ADVECTS INTO THE AREA AND CLOUDS ERODE THROUGH THE DAY TOMORROW. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...KAS LONG TERM...GEOGERIAN AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
427 PM EDT TUE APR 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 329 PM EDT TUE APR 8 2014 MID LEVEL RIDGING CURRENTLY OVER EASTERN KENTUCKY...WILL GIVE WAY TO A MID LEVEL TROUGH THIS EVENING. SCATTERED SHOWERS AND EVEN A FEW THUNDERSTORMS HAVE DEVELOPED UPSTREAM ACROSS WESTERN KENTUCKY INTO CENTRAL INDIANA. THIS ACTIVITY WILL VERY SLOWLY DRIFT SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING...REACHING THE I-75 CORRIDOR BETWEEN 7 AND 8 PM. MEANWHILE...DEWPOINTS HAVE MIXED OUT QUITE WELL ACROSS EASTERN KENTUCKY WITH A FEW PLACES GETTING CLOSE TO 25% RELATIVE HUMIDITY. THIS COULD BE A LIMITING FACTOR ON PRECIPITATION AS IT TRIES TO SPREAD INTO THE AREA THIS EVENING. HOWEVER...HRRR AND RAP BOTH SHOW SOME ACTIVITY MAKING ITS WAY ACROSS THE AREA SO WILL MAINTAIN THE LOW POPS THROUGH THE EVENING AND OVERNIGHT HOURS AS IT DRIFTS SOUTHEAST AND SLOWLY WEAKENS. NAM SEEMS OVERLY AGGRESSIVE ON GENERATING MORE SUBSTANTIAL PRECIPITATION ACROSS THE HIGHER TERRAIN TONIGHT. GIVEN VERY LITTLE SUPPORT FOR THIS AND THE AMBIENT DRY CONDITIONS IN PLACE...NOT CONFIDENT THE NAM HAS A GOOD HANDLE ON THINGS. MID LEVEL RIDGING WILL BUILD BACK ACROSS THE AREA ON WEDNESDAY WITH CLOUDS SLOWLY BREAKING UP THROUGH THE DAY. GIVEN HOW LOW DEWPOINTS HAVE GONE IN THE PAST WEEK ON DRY AFTERNOONS...OPTING TO KEEP THINGS WELL BELOW GUIDANCE...BRINGING IN SOME NEAR 25% RELATIVE HUMIDITY VALUES TOMORROW AFTERNOON. WITH CLEAR SKIES LINGERING INTO TOMORROW NIGHT...A COOLER NIGHT IS ON TAP WITH LOWS FALLING INTO THE 30S...ESPECIALLY IN THE VALLEYS...WHERE SOME FROST WILL BE A POSSIBILITY. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 427 PM EDT TUE APR 8 2014 A MORE ZONAL LONG WAVE PATTERN WILL BE IN PLACE ACROSS THE CONUS THROUGH THE FIRST HALF OF THE WEEKEND...WITH SEVERAL SHORT WAVE TROUGHS TRAVERSING THE OHIO VALLEY/GREAT LAKES REGION. AMPLIFICATION WILL THEN ENSUE FOR THE LATTER HALF OF THE WEEKEND AND INTO EARLY NEXT WEEK...AS FULL LATITUDE TROUGHING TAKES SHAPE ACROSS THE CENTRAL CONUS AND WORKS ITS WAY EAST. THERE IS DECENT MODEL AGREEMENT THROUGH THE FIRST PORTION OF THE EXTENDED...AND THEN LARGER DIFFERENCES CROP UP WITH THE EVOLUTION OF THE DEEPER AND MORE SIGNIFICANT SYSTEM TO AFFECT THE AREA BY EARLY NEXT WEEK. AS SUCH...HAVE STUCK CLOSE TO A BLEND...ALTHOUGH DID FAVOR A SLIGHTLY SLOWER TIMING OF THE HIGHER POPS ASSOCIATED WITH THE DEEPER SYSTEM...SINCE MODELS HAVE GENERALLY TRENDED THIS WAY OVER THE PAST FEW RUNS. DRY AND MILD WEATHER WILL REIGN ACROSS EASTERN KENTUCKY THROUGH THURSDAY AS HIGH PRESSURE SETTLES SOUTHEAST OF THE AREA...WITH GUSTY SOUTH TO SOUTHWEST WINDS HELPING TO BUMP TEMPERATURES UP INTO THE LOW TO MID 70S. A COLD FRONT WILL THEN SLOWLY SAG SOUTHEAST TOWARDS THE AREA LATE THURSDAY NIGHT THROUGH FRIDAY NIGHT...WITH SOME UPPER LEVEL SUPPORT AT TIMES. THERE IS SOME QUESTION AS TO HOW FAR SOUTH THE BOUNDARY WILL MAKE IT INTO OUR AREA...SO STUCK CLOSE TO THE LATEST BLEND AND THE INHERITED POPS...WITH THE OVERALL BETTER CHANCES NORTH...AND LESS TO THE SOUTH. SATURDAY THROUGH SUNDAY...BROAD RIDGING ALOFT WILL KEEP DRY WEATHER IN PLACE ACROSS THE COMMONWEALTH...WITH HIGHS RETURNING TO THE LOW TO MID 70S. DEEP TROUGHING WILL BEGIN TO INFLUENCE FROM THE WEST BY MONDAY...HOWEVER WITH THE NOTED SLOWER TREND...WILL CONTINUE TO CARRY THE HIGHEST POPS MONDAY NIGHT INTO TUESDAY MORNING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 242 PM EDT TUE APR 8 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH MUCH OF THE PERIOD AT THE TAF SITES. A MID LEVEL TROUGH WILL DROP SOUTHEAST LATE THIS EVENING...BRINGING A SOME SCATTERED SHOWERS TO PORTIONS OF EASTERN KENTUCKY. HOWEVER...THIS ACTIVITY IS NOT ANTICIPATED TO BE ALL THAT WIDESPREAD AND MAY SHOW A WEAKENING TREND AS IT DRIFTS SOUTHEAST ACROSS THE AREA. IF WE CAN GENERATE SOME RAIN AND SATURATE THINGS ENOUGH...WE COULD SEE A BRIEF PERIOD OF MVFR CIGS TONIGHT. HOWEVER...GIVEN HOW WELL DEWPOINTS HAVE COME DOWN THIS AFTERNOON...THIS MAY BE A SIGNIFICANT TASK. SO FOR NOW...GOING TO GO WITH A MORE OPTIMISTIC TAF AND KEEP THINGS VFR. IF CIGS DO LOWER TONIGHT...THEY SHOULD QUICKLY BOUNCE BACK UP EARLY TOMORROW MORNING AS DRIER AIR ADVECTS INTO THE AREA AND CLOUDS ERODE THROUGH THE DAY TOMORROW. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...GEOGERIAN AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
329 PM EDT TUE APR 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 329 PM EDT TUE APR 8 2014 MID LEVEL RIDGING CURRENTLY OVER EASTERN KENTUCKY...WILL GIVE WAY TO A MID LEVEL TROUGH THIS EVENING. SCATTERED SHOWERS AND EVEN A FEW THUNDERSTORMS HAVE DEVELOPED UPSTREAM ACROSS WESTERN KENTUCKY INTO CENTRAL INDIANA. THIS ACTIVITY WILL VERY SLOWLY DRIFT SOUTHEAST THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING...REACHING THE I-75 CORRIDOR BETWEEN 7 AND 8 PM. MEANWHILE...DEWPOINTS HAVE MIXED OUT QUITE WELL ACROSS EASTERN KENTUCKY WITH A FEW PLACES GETTING CLOSE TO 25% RELATIVE HUMIDITY. THIS COULD BE A LIMITING FACTOR ON PRECIPITATION AS IT TRIES TO SPREAD INTO THE AREA THIS EVENING. HOWEVER...HRRR AND RAP BOTH SHOW SOME ACTIVITY MAKING ITS WAY ACROSS THE AREA SO WILL MAINTAIN THE LOW POPS THROUGH THE EVENING AND OVERNIGHT HOURS AS IT DRIFTS SOUTHEAST AND SLOWLY WEAKENS. NAM SEEMS OVERLY AGGRESSIVE ON GENERATING MORE SUBSTANTIAL PRECIPITATION ACROSS THE HIGHER TERRAIN TONIGHT. GIVEN VERY LITTLE SUPPORT FOR THIS AND THE AMBIENT DRY CONDITIONS IN PLACE...NOT CONFIDENT THE NAM HAS A GOOD HANDLE ON THINGS. MID LEVEL RIDGING WILL BUILD BACK ACROSS THE AREA ON WEDNESDAY WITH CLOUDS SLOWLY BREAKING UP THROUGH THE DAY. GIVEN HOW LOW DEWPOINTS HAVE GONE IN THE PAST WEEK ON DRY AFTERNOONS...OPTING TO KEEP THINGS WELL BELOW GUIDANCE...BRINGING IN SOME NEAR 25% RELATIVE HUMIDITY VALUES TOMORROW AFTERNOON. WITH CLEAR SKIES LINGERING INTO TOMORROW NIGHT...A COOLER NIGHT IS ON TAP WITH LOWS FALLING INTO THE 30S...ESPECIALLY IN THE VALLEYS...WHERE SOME FROST WILL BE A POSSIBILITY. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 329 PM EDT TUE APR 8 2014 LONG TERM DISCUSSION WILL FOLLOW SHORTLY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 242 PM EDT TUE APR 8 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH MUCH OF THE PERIOD AT THE TAF SITES. A MID LEVEL TROUGH WILL DROP SOUTHEAST LATE THIS EVENING...BRINGING A SOME SCATTERED SHOWERS TO PORTIONS OF EASTERN KENTUCKY. HOWEVER...THIS ACTIVITY IS NOT ANTICIPATED TO BE ALL THAT WIDESPREAD AND MAY SHOW A WEAKENING TREND AS IT DRIFTS SOUTHEAST ACROSS THE AREA. IF WE CAN GENERATE SOME RAIN AND SATURATE THINGS ENOUGH...WE COULD SEE A BRIEF PERIOD OF MVFR CIGS TONIGHT. HOWEVER...GIVEN HOW WELL DEWPOINTS HAVE COME DOWN THIS AFTERNOON...THIS MAY BE A SIGNIFICANT TASK. SO FOR NOW...GOING TO GO WITH A MORE OPTIMISTIC TAF AND KEEP THINGS VFR. IF CIGS DO LOWER TONIGHT...THEY SHOULD QUICKLY BOUNCE BACK UP EARLY TOMORROW MORNING AS DRIER AIR ADVECTS INTO THE AREA AND CLOUDS ERODE THROUGH THE DAY TOMORROW. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...GEOGERIAN AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
242 PM EDT TUE APR 8 2014 .UPDATE... ISSUED AT 242 PM EDT TUE APR 8 2014 EASTERN KENTUCKY REMAINS UNDER THE INFLUENCE OF MID LEVEL RIDGING THIS AFTERNOON...PROVIDING A PLEASANT DAY ACROSS THE AREA. MORNING CLOUD COVER HAS TURNED INTO A SCATTERED DECK OF CUMULUS ACROSS THE AREA. UPSTREAM...MID LEVEL TROUGH CONTINUES TO SLOWLY PUSH SOUTHEAST ACROSS INDIANA...SOUTHWARD INTO WESTERN KENTUCKY. SCATTERED SHOWERS AND EVEN A FEW ISOLATED THUNDERSTORMS HAVE DEVELOPED IN ASSOCIATION WITH THIS FEATURE. BASED ON THE TIMING AND LATEST HI RES GUIDANCE...STILL LOOKS LIKE A LATE ARRIVAL TIME FOR EASTERN KENTUCKY WITH ANY SHOWERS HOLDING OFF UNTIL AT LEAST 7 PM THIS EVENING. THUS...WILL MAINTAIN THE DRY FORECAST THROUGH THE REMAINDER OF THE AFTERNOON AND INTO THE EARLY EVENING HOURS. UPDATE ISSUED AT 947 AM EDT TUE APR 8 2014 UPDATED THIS MORNING TO ALLOW FOR A PERIOD OF PARTLY CLOUDY SKIES THROUGH THE MORNING AND AFTERNOON HOURS AS SUBSIDENCE AHEAD OF AN APPROACHING TROUGH ALLOWS FOR SEVERAL BREAKS IN THE CLOUD COVER. THIS MID LEVEL TROUGH WILL PUSH SOUTHEAST ACROSS CENTRAL KENTUCKY THIS EVENING...AND INTO SOUTHEAST KENTUCKY TONIGHT. LATEST HRRR AND RAP CONTINUE TO SHOW PLENTY OF SCATTERED RAIN SHOWER ACTIVITY AS IT PUSHES INTO THE AREA. BEST CONCENTRATION OF SHOWER ACTIVITY LOOKS TO OCCUR SOUTH OF A LINE FROM MOUNT STERLING...TO PIKEVILLE. AS THE WAVE EXITS SOUTHEAST TONIGHT...UPSLOPE FLOW AND SOME LINGERING MOISTURE MAY LEAD TO A PERIOD OF LIGHT RAIN ACROSS THE HIGHER TERRAIN AREAS. AS FOR THUNDER...TIMING IS NOT GREAT AS PRECIPITATION MAY NOT ARRIVE UNTIL NEAR OR AFTER SUNSET WITH INSTABILITY ALREADY STARTING TO DECREASE BY THIS TIME. ON TOP OF THIS...SHEAR REMAINS MINIMAL THIS EVENING...WHICH WILL LIMIT ANY SUSTAINED UPDRAFTS AND THEREFORE LIMITING THE THUNDER POTENTIAL. OVERALL RAIN SHOWER COVERAGE COULD BE ENOUGH TO JUSTIFY HIGHER POPS...BUT THE GFS CONTINUES TO SHOW VERY LITTLE MEASURABLE RAIN THIS EVENING...SO WILL WAIT FOR THE NEW GUIDANCE BEFORE INCREASING OR DECREASING POPS. WITH THE BREAKS IN CLOUD COVER...HIGHS SHOULD RECOVER TOE AROUND 60 THIS AFTERNOON. UPDATED LATEST HOURLY AND DEWPOINT GRIDS TO REFLECT CURRENT CONDITIONS. UPDATE ISSUED AT 735 AM EDT TUE APR 8 2014 UPDATED THE FORECAST TO SLOW DOWN THE ONSET OF PRECIPITATION FOR TODAY. ACCORDING TO THE MODELS...IT SHOULD BE RAINING NOW SO DECIDED TO HOLD OFF THE PRECIPITATION UNTIL THE UPPER TROUGH MOVES THROUGH THE AREA LATER TODAY. THE REST OF THE FORECAST IS ON TRACK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 308 AM EDT TUE APR 8 2014 LOW CLOUDS HAVE SPREAD ACROSS THE AREA TONIGHT AS AN UPPER LEVEL DISTURBANCE WORKS ACROSS THE AREA. UNFORTUNATELY...THIS IS THE FIRST OF TWO UPPER TROUGHS WITH ANOTHER UPPER TROUGH EXPECTED TO MOVE ACROSS THE AREA TONIGHT. WITH THE UPPER TROUGH COMES SOME COLD AIR ALOFT. THIS WILL CAUSE THE CONDITIONS ACROSS THE AREA TO BE FAIRLY UNSTABLE THIS AFTERNOON AND EVENING. SO ALONG WITH SOME SCATTERED SHOWERS THAT ARE POSSIBLE...THERE MAY ALSO BE SOME ISOLATED THUNDERSTORMS. THESE ARE THE TYPE OF STORMS THAT WILL BE CAPABLE OF PRODUCING SOME GRAUPEL. HIGH PRESSURE WILL BE BUILDING INTO THE AREA ON WEDNESDAY. TEMPERATURES WILL REMAIN NEAR NORMAL DURING THE PERIOD WITH HIGHS IN THE 60S AND LOWS TONIGHT NEAR 40. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 358 AM EDT TUE APR 8 2014 MODELS CONTINUE TO SHOW GOOD AGREEMENT THROUGH THE MID TERM...AS THE PERIOD STARTS OFF WITH AN EXITING UPPER LEVEL TROUGH THURSDAY...AND A FLATTENING OF THE LONGWAVE PATTERN ACROSS KY. A SHALLOW TROUGHING PATTERN WILL TAKE SHAPE TO OUR NORTH...WITH A CLOSED LOW PASSING EASTWARD ACROSS SOUTHERN CANADA/GREAT LAKES REGION. EXPECT MUCH OF THE PRECIPITATION FROM THIS SYSTEM TO REMAIN TO OUR NORTH NEARER TO THE SURFACE LOW...WHICH WILL BE PASSING THROUGH JAMES BAY AND THEN NEWARD THURSDAY THROUGH THURSDAY NIGHT. HOWEVER...A ELONGATED SURFACE COLD FRONT WILL STRETCH FROM THIS LOW TO A WEAKER SURFACE LOW LOCATED OVER TX. WHILE THE ABOVE-MENTIONED NORTHERN CANADIAN LOW APPEARS TO BE VERY PROGRESSIVE...THE SOUTHERN LOW WILL REMAIN NEARLY STATIONARY. A LINE OF PRECIPITATION WILL DEVELOP ALONG THE LEADING EDGE OF THIS FRONTAL SYSTEM...FIRST MOVING FROM NW TO SE THROUGH KY THURSDAY NIGHT...AND THEN BECOMING ORIENTED FROM W TO E DUE TO THE NORTHERN LOW PROGRESSING MORE QUICKLY DURING THE DAY FRIDAY. SOME LOCALIZED SURFACE LOWS WILL ALSO DEVELOP ALONG THE LINE...HELPING TO BOOST INSTABILITY ACROSS EASTERN KY. LATEST GFS FORECAST SOUNDINGS ARE SHOWING GOOD POTENTIAL FOR CONVECTION WITHIN THIS PRECIPITATION...WITH GOOD FRONTAL LIFT...LOW LEVEL MOISTURE AND MID/UPPER LEVEL DRYING...AND DECENT SHEER. OBVIOUSLY...BEST TIMES FOR CONVECTION WILL BE IN THE AFTERNOON /FRIDAY/...WHEN DAYTIME HEATING ALLOWS ANY LOW LEVEL INVERSIONS TO BREAK AND MAXIMUM CAPE VALUES ARE REACHED. CAPE VALUES ARE MARGINAL...BUT EXPECT FRONTAL LIFT...LLVL WIND SHEAR...AND WARM BUOYANT PARCELS TO BE ABLE TO LIFT AND CREATE SOME TSTMS ACROSS THE AREA. THE W TO E ORIENTED FRONT WILL FINALLY MOVE S OF THE AREA SATURDAY...WITH ANY REMAINING PRECIPITATION ACROSS THE REGION COMING TO AN END AS SURFACE HIGH PRESSURE BRIEFLY RETURNS TO EASTERN KY. IN THE UPPER LEVELS...BRIEF RIDGING WILL TAKE HOLD AS WELL. HOWEVER...YET ANOTHER DEEPENING LOW IS EXPECTED ACROSS THE WESTERN PLAINS BY SUNDAY...WITH SEVERAL SMALLER SHORTWAVES DEVELOPING AS FAR EAST AS THE UPPER GREAT LAKES. MEANWHILE...IT IS ALSO AT THIS POINT THAT LONG RANGE MODELS START TO DIVERGE IN SOLUTIONS...SO WILL RELY ON THE ALLBLEND FOR ANY SURFACE PRECIP FEATURES AS FAR AS TIMING AND EXTENT/LOCATION. AT THE SURFACE...EXPECT A LOW PRESSURE SYSTEM TO DEVELOP OUT OF THIS SHORTWAVE ACROSS THE NORTHERN PLAINS ON SATURDAY...THEN SHIFT ENE TO THE UPPER GREAT LAKES BY LATE SATURDAY NIGHT. A COLD FRONT WILL EXTEND FROM THIS SURFACE LOW...BRINGING THE CHANCE FOR RAIN AND ENOUGH FRONTAL LIFT THAT SOME THUNDERSTORMS CANNOT BE RULED OUT AHEAD OF THE FRONT...WITH PRECIP EXPECTED TO ARRIVE SUNDAY NIGHT INTO MONDAY. WHILE THE PRECIP IS UNDERWAY MONDAY...LATEST ECMWF AND GFS40 SHOW THE UPPER LEVEL TROUGH CONTINUING TO DEEPEN AS IT MOVES EAST ACROSS THE CENTRAL PLAINS MONDAY...REACHING THE MISSISSIPPI RIVER VALLEY MONDAY NIGHT...AND THEN A CLOSED LOW DEVELOPING JUST TO THE SE OF KY BY TUESDAY NIGHT. WITH THAT...EXPECT PRECIP TO CONTINUE ACROSS KY INTO THE OVERNIGHT HOURS MONDAY NIGHT...WITH DRY AIR QUICKLY WORKING IN FROM THE NORTH BY 12Z TUESDAY JUST BEHIND THE FRONTAL PASSAGE THROUGH EASTERN KY. TOOK OUT ANY MENTION OF THUNDER AFTER 0Z TUESDAY...AS LATEST GFS40 SOUNDINGS SHOW AN IMPRESSIVE LOW LEVEL WARMING LAYER/INVERSION...AND WINDS UNSUPPORTIVE OF BEING ABLE TO LIFT PARCELS. OBVIOUSLY THIS FAR OUT IN THE FORECAST...THE TIMING OF SUCH FEATURES...AS WELL AS THE RESULTING POPS AND QPF...WILL NEED TO BE TWEAKED AND ADJUSTED AS WE HEAD CLOSER TO THE ONSET. HOWEVER...STILL FAIRLY IMPRESSED WITH THE AGREEMENT SO FAR BETWEEN THE GFS...GEM...AND ECMWF...AND FOR THE NAM IN THE MID TERM AS WELL. AS FAR AS TEMPERATURES...EXPECT LLVL WINDS TO REMAIN PREDOMINATELY OUT OF THE SOUTH DURING THE EXTENDED PERIOD...WITH THE EXCEPTION OF THE TWO FRONTAL PASSAGES. AS SUCH...DAYTIME HIGHS WILL CLIMB WELL ABOVE SEASONABLE NORMS MOST DAYS...INTO THE UPPER 60S AND LOW 70S. THE COLDEST DAYS WILL BE FRIDAY...AS THE FRONT BECOMES ELONGATED OVER KY AND COOLER AIR IS ALLOWED TO FILTER IN FROM THE NORTH...AS WELL AS AFTER THE FRONTAL PASSAGE AT THE END OF THE PERIOD...WHERE DAYTIME HIGHS ON TUESDAY WILL ONLY BOUNCE BACK INTO THE MID 50S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 242 PM EDT TUE APR 8 2014 VFR CONDITIONS WILL LIKELY PERSIST THROUGH MUCH OF THE PERIOD AT THE TAF SITES. A MID LEVEL TROUGH WILL DROP SOUTHEAST LATE THIS EVENING...BRINGING A SOME SCATTERED SHOWERS TO PORTIONS OF EASTERN KENTUCKY. HOWEVER...THIS ACTIVITY IS NOT ANTICIPATED TO BE ALL THAT WIDESPREAD AND MAY SHOW A WEAKENING TREND AS IT DRIFTS SOUTHEAST ACROSS THE AREA. IF WE CAN GENERATE SOME RAIN AND SATURATE THINGS ENOUGH...WE COULD SEE A BRIEF PERIOD OF MVFR CIGS TONIGHT. HOWEVER...GIVEN HOW WELL DEWPOINTS HAVE COME DOWN THIS AFTERNOON...THIS MAY BE A SIGNIFICANT TASK. SO FOR NOW...GOING TO GO WITH A MORE OPTIMISTIC TAF AND KEEP THINGS VFR. IF CIGS DO LOWER TONIGHT...THEY SHOULD QUICKLY BOUNCE BACK UP EARLY TOMORROW MORNING AS DRIER AIR ADVECTS INTO THE AREA AND CLOUDS ERODE THROUGH THE DAY TOMORROW. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...JJ LONG TERM...JMW AVIATION...KAS
AREA FORECAST DISCUSSION
NWS GRAY ME
531 PM EDT TUE APR 8 2014 .SYNOPSIS... HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST TONIGHT THROUGH WEDNESDAY AND WILL SHIFT OFFSHORE WEDNESDAY NIGHT AND THURSDAY. A COLD FRONT WILL APPROACH FROM THE WEST THURSDAY NIGHT AND WILL PUSH OFFSHORE BY FRIDAY MORNING. WEAK HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY. WEAK LOW PRESSURE WILL MOVE SOUTH OF NEW ENGLAND FRIDAY NIGHT AND SATURDAY. WEAK HIGH PRESSURE BUILDS OVER THE REGION SUNDAY WITH LOW PRESSURE AND A SLOW MOVING COLD FRONT APPROACHING FROM THE WEST MONDAY THROUGH TUESDAY. && .NEAR TERM /TONIGHT/... 530PM UPDATE... A FEW SHOWERS CONTINUE TO MOVE OFF TO THE EAST ACROSS NEW HAMPSHIRE AND MAINE THIS EVENING ASSOCIATED WITH THE FRONTAL BOUNDARY AND LEADING EDGE OF COLD ADVECTION ALOFT. SOME THUNDER IS POSSIBLE AS THE SHOWERS GROW A LITTLE MORE INTENSE. HAVE UPDATED HOURLY POP FORECAST AND RELIED HEAVILY ON THE HRRR MODEL WHICH SEEMS TO BE HANDLING THIS BAND OF SHOWERS FAIRLY WELL. FOG HAS MOVED IN TO COASTAL AREAS WHERE SOUTHERLY WINDS CONTINUE. HOWEVER... AS WINDS SHIFT BEHIND THE FRONT THIS FOG WILL LIKELY CLEAR OUT. ORIGINAL DISCUSSION... LOW PRESSURE WILL PASS TO OUR NORTHWEST THIS AFTERNOON AND THIS EVENING AND IT WILL BRING A TRAILING COLD FRONT ACROSS THE REGION. THERE WILL BE DECENT COLD AIR ADVECTION BEHIND THE FRONT AS OUR WINDS SHIFT ACROSS TO THE NORTHWEST AND THIS WILL GIVE US SOME FAVORABLE UPSLOPE CONDITIONS OVERNIGHT. EXPECTING TO SEE A FEW SNOW SHOWERS ACROSS THE MOUNTAINS OVERNIGHT...HOWEVER ANY ACCUMULATIONS WILL BE VERY LIGHT. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... A RIDGE OF HIGH PRESSURE WILL BUILD IN TOMORROW...THE TIGHTENING PRESSURE GRADIENT WILL KICK OFF SOME GUSTY WINDS THROUGH TOMORROW EVENING AND THEN THE RIDGE WILL CREST OVERHEAD. WE SHOULD SEE SOME DECENT RADIATIONAL COOLING ON WEDNESDAY NIGHT AS THE WINDS GO LIGHT UNDER CLEAR SKIES...LOW TEMPERATURES WILL RUN ABOUT 5 DEGREES BELOW NORMAL. && .LONG TERM /THURSDAY THROUGH TUESDAY/... A WARM SOUTHWEST FLOW WILL BE OVER THE REGION THURSDAY AS HIGH PRESSURE MOVES OFF THE COAST. BY LATE THURSDAY NIGHT AND EARLY FRIDAY A COLD FRONT WILL MOVE THRU NORTHERN NEW ENGLAND WITH SCATTERED SHOWERS TO QUICKLY MOVE THRU THE AREA. SKIES CLEAR ON FRIDAY WITH A DOWNSLOPING NW FLOW. BY FRIDAY NIGHT MODELS SHOW THE POTENTIAL OF ANOTHER FAST MOVING LOW PRESSURE SYSTEM THAT WILL MOVE RAPIDLY NE THRU NEW ENGLAND AND BRING ANOTHER ROUND OF SHOWERS THAT WOULD BE ENDING BY MIDDAY SATURDAY. HIGH PRESSURE BRIEFLY BUILDS IN LATE SATURDAY INTO EARLY SUNDAY WITH DRIER AIR BEFORE A STRONG WARM ADVECTION SETS UP BY MID SUNDAY INTO MONDAY AND TO BE ACCOMPANIED BY SCATTERED SHOWERS. A COLD FRONT WILL MOVE THRU MONDAY EVENING BRINGING COOLER AND DRIER AIR BACK INTO THE REGION. WITH THE FAST MOVING SYSTEMS IN THE OUTLOOK PERIOD STAYED CLOSE TO THE SUPERBLEND MODEL FOR TIMING OF PCPN. INCREASED MAX/MIN TEMPERATURES A FEW DEGREES FOR SUNDAY AND MONDAY WITH THE STRONG WARM ADVECTION. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... SHORT TERM...CONDITIONS WILL BE IMPROVING THROUGHOUT THE EVENING TO IFR AS CLOUDS WILL LIFT WHEN A COLD FRONT PUSHES THROUGH THE AREA. VFR CONDITIONS WILL THEN PERSIST THROUGH THE REMAINDER OF THE PERIOD. LONG TERM...MVFR/IFR POSSIBLE THURSDAY NIGHT IN SHOWERS AND AGAIN FRIDAY NIGHT INTO EARLY SATURDAY. OTHERWISE MAINLY VFR. && .MARINE... SHORT TERM...WINDS WILL DECREASE THIS EVENING...HOWEVER SEAS WILL REMAIN WITHIN SCA LEVELS. HIGH PRESSURE WILL BUILD IN TOMORROW AND THIS WILL HELP KICK OFF SOME GUSTY WINDS UP TO 30 KNOTS OUT OF THE NORTHWEST TOMORROW...SO IT APPEARS THAT THE SCA WILL REMAIN THROUGHOUT THE DAY TOMORROW. LONG TERM...WINDS AND SEAS INCREASE THURSDAY INTO THURSDAY NIGHT IN AN INCREASING SOUTH FLOW WITH SCA CONDITIONS LIKELY AND GUSTS UP TO GALE FORCE POSSIBLE OVER THE OPEN WATERS. WINDS DROP BELOW SCA LEVELS FRIDAY BUT MAY INCREASE AGAIN FRIDAY NIGHT INTO SATURDAY. && .HYDROLOGY... THE SUNCOOK RIVER AT NORTH CHICHESTER REMAINS IN A RIVER FLOOD WARNING. SMALL RIVERS AND STREAMS WILL CONTINUE TO RISE THROUGH THE NIGHT DUE TO RUNOFF FROM SNOW MELT AND RAINFALL EARLIER IN THE DAY... HOWEVER ANY FLOODING WILL BE VERY MINOR. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR ANZ150>154. && $$ NEAR TERM UPDATE... KIMBLE SHORT TERM... KISTNER LONG TERM... MARINE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
223 PM EDT TUE APR 8 2014 .SYNOPSIS... A COLD FRONT MOVES OFF THE MID ATLANTIC COAST TODAY. A TROUGH OF LOW PRESSURE LINGERS ALONG THE COAST THROUGH TONIGHT. HIGH PRESSURE BUILDS BACK INTO THE AREA WEDNESDAY THROUGH FRIDAY. A COLD FRONT APPROACHES FROM THE NORTH FRIDAY NIGHT. && .NEAR TERM /THROUGH TONIGHT/... A SLOW FRONT WILL SLOWLY MOVE THROUGH THE AREA THIS AFTERNOON. WITH THE UPPER FLOW STILL SOUTHWEST AS CAN BE SEEN ON VWP AND SOME PROFILERS THE FRONT WILL MOVE EVEN SLOWER AS IT PUSHES TO THE COAST. RADAR CONTINUES TO SHOW SHOWERS OVER NORTHEAST NORTH CAROLINA. THE HRRR AND RUC DEPICTS THESE ECHOES WELL ON ITS SIMULATED REFLECTIVITY AND THIS SHOWS THE ECHOES VERY SLOWLY SINKING SOUTHEAST. CHANGED POPS TO KEEP THEM A LITTLE HIGHER LONGER ESPECIALLY OVER NORTHEAST NORTH CAROLINA. MILD WITH TEMPERATURES CHANGING VERY LITTLE AND HIGHS MID 60S TO LOW 70S. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... TROF SHIFTS EAST TONIGHT BUT YET ANTHR IN A SERIES OF UPPER LEVEL DISTURBANCES APPRCHS FROM THE WEST AFTR MIDNITE. EXPECT MOST OF THIS MSTR TO GO INTO CLOUD COVERAGE...SO KEPT THE FCST DRY FOR NOW. ANY PCPN THAT DOES DVLP SHOULD STAY IN NC. LOWS IN THE 40S. HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST WED. BEFORE ANY DRYING OCCURRS...LAST OF THE S/W`S PROGGED TO TRACK ACROSS NC DURING THE AFTRN. BOTH GFS/NAM SHOW MINIMAL AMTS OF MSTR ACROSS SRN CNTYS. GIVEN THIS MSTR MOVES THRU DRNG PEAK HEATING HRS...ADDED ISLTD SHWRS TO SRN CNTYS (MAINLY S OF RT 58). HIGHS IN THE 60S. ERN TROF FINALLY LIFTS OUT ALLOWING RIDGING TO SETTLE IN ACROSS THE AREA WED NITE AND THURS. TSCTNS VOID OF ANY SGNFCNT MSTR SO EXPECT A M CLR TO PT CLDY PRD. WEAK CAA DMNSHS SETTING UP DECENT RADIATIONAL COOLING WED NITE. LOWS M-U30S NRN/WRN CNTYS TO U30S-L40S SRN AREAS. PT TO MSTLY SUNNY THURSDAY. HIGHS U60S-L70S. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... SEASONABLY WARM TEMPERATURES WILL HEADLINE THE EXTENDED PERIOD FORECAST WITH CHANCES OF SHOWERS EARLY NEXT WEEK. ZONAL FLOW ALOFT TO BEGIN THE EXTENDED AS A SHORTWAVE TRACKS ACROSS SE CANADA THURS NIGHT-FRI MORNING. THIS WILL PUSH A WEAK COLD FRONT TOWARD THE CTRL APPALACHIANS FRI. HIGH PRESSURE WILL CENTER OVER THE WRN ATLANTIC FRI...RIDGING SWWD INTO THE GULF STATES. HIGH PRESSURE AND WLY FLOW ALOFT WILL LIMIT ANY RETURN MOISTURE REGARDLESS OF SLY FLOW ON THE BACK SIDE OF THE SFC HIGH. THIS WILL KEEP THE LOCAL AREA DRY ON FRI. CYCLONIC FLOW WILL INCREASE OVER THE ERN CONUS FRI AS NRN STREAM ENERGY DIGS OVER THE MIDWEST. MODELS DEVELOP A WAVE ALONG THE FRONT OVER NRN VA/MD... WHICH MAY ENHANCE RAINFALL IN THAT REGION. WILL MAINTAIN SLIGHT CHANCE-LOW END CHANCE POPS OVER THE NRN LOCAL AREA...INCLUDING THE MD ERN SHORE FRI-FRI NIGHT. MODELS THEN DIFFER ON PUSHING THE WEAK FRONT THROUGH THE LOCAL AREA SAT. TRENDED TOWARD THE GFS...THINKING THE FRONT WILL HAVE TROUBLE PUSHING THROUGH THE REGION. ECMWF MORE ROBUST WITH SHORTWAVE TRAVERSING THE REGION FRI NIGHT-THURS MORNING...PUSHING THE FRONT THRU THE LOCAL AREA. REGARDLESS OF WHICH MODEL VERIFIES...LACK OF MOISTURE AND DYNAMICS...AS WELL AS SUBSIDENCE BEHIND THE FRONT WILL KEEP THE FORECAST DRY SAT. SUNDAY WILL ALSO BE DRY AS HIGH PRESSURE/SUBSIDENCE DOMINATES. MEANWHILE... A DEEPENING TROUGH OVER THE WRN CONUS/INTERMOUNTAIN WEST WILL AMPLIFY THE FLOW OVER THE ERN CONUS. AN ASSOCIATED COLD FRONT WILL PROPAGATE EWD OVER THE MIDWEST INTO THE OH VALLEY SUN NIGHT-MON MORNING. MEANINGFUL DIFFERENCES EXIST IN THE MODELS...WITH THE GFS 12+ HRS FASTER WITH THE FRONT/MOISTURE THAN ITS ECMWF COUNTERPART. HAVE OPTED FOR SLIGHT CHANCE-LOW END CHANCE POPS BEGINNING MON TO ACCOUNT FOR UNCERTAINTY. DAYTIME TEMPS WILL BE SEASONABLY WARM...GENERALLY IN THE LOW-MID 70S. SLIGHTLY COOLER SAT WITH FRONTAL PASSAGE AND NLY WINDS. SLY WINDS FRI AND SUN-MON WILL RESULT IN LOCALLY COOLER TEMPS ALONG THE COASTAL ERN SHORE. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... CDFNT TO THE CST EARLY THIS AFTN...WILL CONT TO THE E THROUGH LATE THIS AFTN/EARLY EVE. LINGERING MVFR CIGS MNLY ACRS CSTL SE VA/NE NC ALG W/ ISOLD SHRAS (ABT TO EXIT THE CST)...OTRW...BKN-OVC VFR CIGS MNLY FM 5-25KFT. GUSTY WNW WNDS TO 20-25 KT WANE THIS EVE...BECOMING NNW TNGT. OCNL GUSTY NNE WNDS (TO 20 KT) WED...ESP AT THE CST. TROUGH ALOFT CROSSING THE RGN TNGT THROUGH EARLY WED AFTN W/ CONTD OCNL BKN VFR CIGS...PTNTLLY AN ISOLD SHRA AS WELL. AFT THAT...HIGH PRESSURE BUILDS INTO THE REGION W/ VFR AND DRY THE REST OF THE WEEK. && .MARINE... A COLD FRONT WILL CROSS THE WATERS LATE THIS MORNING INTO THE AFTERNOON WITH WINDS BECOMING W-NW BY AFTN AND N-NW TONIGHT. WINDS REMAIN AOA SCA THRESHOLDS THRU NOON BEFORE DIMINISHING TO 10-15 KT OR LESS THIS AFTERNOON. LACK OF CAA AND STRONG GRADIENT WINDS (HIGH PRESSURE BUILDING IN FROM THE SW) WILL PRODUCE SUB-SCA WINDS (AOB 15 KT) OVER THE WATERS TONIGHT. SEAS WILL BE SLOW TO SUBSIDE ACROSS THE NORTHERN WATERS TODAY...BUT SHOULD DROP BELOW 5 FT AROUND OR SHORTLY AFTER 8 PM. SEAS ACROSS THE SOUTHERN WATERS MAY DROP BELOW 5 FT AS EARLY AS NOON TODAY DUE TO SW FLOW REGIME AND MAY BE ABLE TO DROP SCA`S QUICKER THAN CURRENTLY FORECAST. WILL CONTINUE TO MONITOR AND ADJUST HEADLINES AS NECESSARY. HIGH PRESSURE BUILDS OVER THE WATERS WEDS-THURS RESULTING IN SUB-SCA CONDITIONS. A WEAK COLD FRONT WILL APPROACH THE WATERS THURSDAY NIGHT-EARLY FRI MORNING...LIKELY STALLING OVER OR JUST NORTH OF THE REGION FRI. && .HYDROLOGY... CONTG FLOOD WARNING FOR LAWRENCEVILLE THROUGH LATE TNGT (FOR MINOR FLOODING). OTRW...RECENT RAINFALL OF 1 TO 1.5 INCHES HAS CAUSED AREA RIVERS TO RISE ONCE AGAIN...MAINLY BTWN 1/2 TO 3/4 BANKFULL...GREATEST ACROSS SOUTHERN MAIN STEM RIVERS. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ650-652- 654. && $$ SYNOPSIS...MPR NEAR TERM...MPR/JAB SHORT TERM...MPR LONG TERM...SAM AVIATION...ALB/JDM MARINE...JDM HYDROLOGY...AKQ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
444 PM EDT TUE APR 8 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 442 PM EDT TUE APR 8 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA AND A TROF EXTENDING FROM HUDSON BAY TO THE WRN GULF OF MEXICO. WEAK SHORTWAVE MOVING THROUGH ONTARIO AND THE UPPER GREAT LAKES HAS PRODUCED SOME MID CLOUDS TODAY ACROSS THE CWA AS NOTED ON VISIBLE SATELLITE IMAGERY. BUT THERE HAVE ALSO BEEN ENOUGH BREAKS OF SUN TO SEND AFTERNOON TEMPS INTO THE 40S WITH EVEN SOME 50S REPORTED SCNTRL UPPER MI (AT LEAST 55F IN KMNM) DESPITE NORTHERLY FLOW ACROSS THE AREA. SFC HIGH PRES RIDGE SHIFTS ACROSS THE UPPER LAKES TONIGHT IN RESPONSE TO BUILDING 5H HGTS OVER THE NRN PLAINS. SFC RDG WILL ALLOW LIGHT/CALM WINDS FOR A GOOD PORTION OF THE NIGHT IN MOST AREAS. ON THE BACKSIDE OF THE RIDGE AND IN ADVANCE OF SHORTWAVE MOVING ACROSS THE SRN CANADIAN ROCKIES...STRENGTHENING WAA/ISENTROPIC ASCENT PATTERN TO THE NW WILL GENERATE SOME PCPN ACROSS MANITOBA INTO NRN ONTARIO TONIGHT. ALTHOUGH HIGH/MID CLOUDS WILL SPREAD SE INTO THE AREA OVERNIGHT...THERE SHOULD BE A LONG ENOUGH PERIOD OF MOSTLY CLEAR SKIES AND RADIATIONAL COOLING TO ALLOW FOR A DECENT TEMP FALL. CONTINUED TO KEEP MINS TOWARD THE LOWER END OF AVBL GUIDANCE...REPRESENTED BY THE BIAS CORRECTED REGIONAL AND GLOBAL GEM. TRADITIONAL INTERIOR COLD SPOTS SHOULD FALL TO THE MID TEENS AND PERHAPS EVEN TO THE LOW TEENS OVER THE E. WEDNESDAY WILL TRANSITION BACK TO THE ABOVE NORMAL TEMPERATURES AS THE UPPER RIDGE CURRENTLY OVER THE WESTERN CONUS SHIFTS EAST ACROSS THE GREAT LAKES REGION. WARM AIR ADVECTION AND Q-VECTOR CONVERGENCE AHEAD OF SHORTWAVE/FRONTAL SYSTEM RIDING ALONG THE US/CANADIAN BORDER WILL SPREAD SOME PASSING MID CLOUDS ACROSS MUCH OF THE CWA. THERE MAY BE ENOUGH MOISTENING IN THE LOWER LEVELS TO ALLOW SOME LIGHT SPRINKLES TO AFFECT THE KEWEENAW PENINSULA. OTHERWISE...THE BEST FORCING WILL GENERALLY STAY NORTH SHIFTING QUICKLY THROUGH THE AREA AND LEADING TO A FILTERED SUNSHINE THROUGH HIGH CLOUDS. STRONG WARMING IN THE LOWER LEVELS THROUGH THE DAY ON WEDNESDAY (850MB TEMPS RISING FROM -2C AT 12Z TO AT LEAST 6C BY 00Z THURSDAY) SHOULD LEAD TO ANOTHER WARM DAY ACROSS THE CWA. WILL CONTINUE TO SHOW HIGHS IN THE UPPER 50S AND LOWER 60S OVER THE WESTERN HALF OF THE CWA AND 40S OVER THE EASTERN 1/3 OF CWA WITH SOUTHWEST WINDS OFF LAKE MICHIGAN. SW WINDS SHOULD BE GUSTY IN THE AFTERNOON (15-25KTS) AND THAT WILL ALLOW THE DOWNSLOPE AREAS ALONG LAKE SUPERIOR TO WARM AND LIMIT LAKE BREEZE COOLING. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 442 PM EDT TUE APR 8 2014 A SOMEWHAT ACTIVE LONG TERM IS IN STORE AS EASTERN CANADIAN MID-LEVEL TROUGHING REDEVELOPS AND SENDS A SERIES OF DISTURBANCES ACROSS THE UPPER GREAT LAKES. WEDNESDAY NIGHT THROUGH THURSDAY...WEAK MID-LEVEL RIDGING WILL BE MOVING TO THE EAST AS A POTENT MID-LEVEL TROUGH ACROSS NORTHERN MANITOBA BEGINS TO TRACK EASTWARD ACROSS FAR NORTHWESTERN ONTARIO. 295K ISENTROPIC LIFT/WAA ACROSS THE FAR EAST THURSDAY EVENING AHEAD OF THIS SYSTEM COULD BRING SOME ISOLATED LIGHT SHOWERS. WHILE MOISTURE IS AVAILABLE IN THE MID LEVELS/5-10KFT...THE LOW-LEVELS REMAIN QUITE DRY. THEREFORE...MOST ACTIVITY SHOULD BE LIMITED TO VIRGA WITH ONLY ISOLATED HEAVIER SHOWERS REACHING THE GROUND. FAVORABLE FORCING FROM THE RIGHT ENTRANCE/LEFT EXIT OF A DEVELOPING 90-100KT UPPER JET STREAK...AND MID-LEVEL Q-VECTOR CONVERGENCE WILL PASS ACROSS NORTHERN WI AND NORTH OF LAKE SUPERIOR WEDNESDAY NIGHT...LEAVING THE AVAILABLE FORCING ACROSS UPPER MI TO A NARROW BAND OF FGEN ALONG A SFC COLD FRONT. OVERALL MOISTURE AVAILABILITY IS LOW...SO EXPECT ANY PRECIPITATION TO BE IN THE FORM OF RAIN SHOWER ACTIVITY IN A NARROW 3 TO 5 HOUR WINDOW ALONG THE FRONT. THE SHOWERS LOOK TO BE QUITE SCATTERED...SO DID NOT FEEL CONFIDENT IN ANYTHING OVER CHANCE POPS. SKIES WILL THEN QUICKLY CLEAR BEHIND THE FRONT AND LEAD TO A MOSTLY SUNNY THURSDAY. THOUGH LOW-LEVEL MOISTURE IS LIMITED...DIURNAL STRATOCUMULUS SHOULD DEVELOP IN THE AFTERNOON AWAY FROM LAKE SHADOWS DOWNWIND OF WESTERLY WINDS. WIND WILL BE OF NOTE WEDNESDAY NIGHT INTO THURSDAY. STRENGTHENING S TO SW GRADIENT FLOW AHEAD OF THE COLD FRONT WILL SPREAD ACROSS THE AREA THROUGH THE NIGHT AS NOTED BY A 50 TO 60KT H8 LLJ. AREAS FAVORED BY S TO SW DOWNSLOPE FLOW WILL REMAIN RELATIVELY WARM WITH GUSTY WINDS THROUGH THE NIGHT. COMBINED WITH A WARM DAY WEDNESDAY AND SFC DEWPOINTS RISING ABOVE 32F...THE SNOWPACK ACROSS UPPER MI MAY BEGIN QUICKLY ERODING. SEE THE HYDROLOGY DISCUSSION FOR MORE INFORMATION. FRIDAY THROUGH SUNDAY...TO EACH THEIR OWN WITH THE 12Z MODEL SUITE BEGINNING FRIDAY...WITH SOLUTIONS FRIDAY EVENING RANGING FROM A STRONG LOW JUST NORTH OF LAKE SUPERIOR/GFS/ TO WEAK RIDGING/NAM/ TO NW FLOW WITH MULTIPLE WEAK WAVES/GEM AND ECMWF/. THE GFS SOLUTION IS A MAJOR DEPARTURE FROM THE PREVIOUS RUNS...BUT THE 12Z ECMWF IS ALSO SHOWING SIMILARITIES WITH THE GFS. THERE IS NOT MUCH CONFIDENCE IN THE FORECAST BEYOND FRIDAY MORNING FOR THIS REASON. WHILE THE OVERALL PATTERN SUGGESTS A WETTER AND COOLER THAN NORMAL STRETCH...TIMING OF PRECIP AS WELL AS DOMINATE PRECIP-TYPE WILL BE DIFFICULT TO FORECAST. GIVEN SOME CONTINUITY FROM RUN TO RUN WITH THE ECMWF...WILL USE THAT TO FORMULATE MUCH OF THE REMAINING FORECAST. A TROUGH AXIS EXTENDING SOUTHWESTWARD FROM A BROAD MID-LEVEL TROUGH OVER HUDSON BAY FRIDAY WILL SWING ACROSS NORTHERN ONTARIO AND GRAZE LAKE SUPERIOR/UPPER MI FRIDAY NIGHT. SOME UPPER-LEVEL SUPPORT FROM THE LEFT-EXIT OF A DEVELOPING UPPER JET STREAK SHOULD BE ENOUGH TO GENERATE ISOLATED LIGHT RAIN SHOWERS ACROSS THE AREA LATE FRIDAY AFTERNOON INTO THE EVENING...ESPECIALLY ACROSS THE EAST HALF. A WEAK RIDGE WILL BRIEFLY LIMIT PRECIP COVERAGE LATE FRIDAY NIGHT INTO SATURDAY MORNING BEFORE BROAD LOW PRESSURE DEVELOPING ACROSS THE CENTRAL PLAINS PUSHES A SFC TROUGH NORTHEASTWARD ACROSS THE UPPER MS VALLEY. THIS SHOULD BRING LIGHT RAIN ACROSS MAINLY THE WESTERN CWA THROUGH THE DAY...ESPECIALLY IN THE AFTERNOON. A COMPLICATED MID-LEVEL PATTERN WILL THEN RESULT IN SEVERAL WAVES OF PRECIPITATION ACROSS THE REGION SUNDAY AND MONDAY. AS DEEP TROUGHING OVER THE GULF OF ALASKA LATE THIS WEEK TRACKS SE TO THE CENTRAL PLAINS...A COMPACT SHORTWAVE WILL EJECT FROM SOUTHERN CALIFORNIA AND ROUND THE LARGER TROUGH...REACHING THE UPPER GREAT LAKES MONDAY MORNING. AS NOTED BEFORE...MODEL AGREEMENT IS QUITE POOR...SO CONFIDENCE ON THIS SCENARIO IS VERY LOW. HOWEVER...IF THIS DEVELOPMENT OCCURS...UPPER MI WOULD BE IN LINE FOR ANOTHER MODERATE TO HEAVY WET SNOWFALL ACROSS THE CENTRAL AND EASTERN CWA. FOR COMPARISON...THE GFS AND GEM DEVELOP THIS SYSTEM/PRECIP ACROSS THE NORTHERN OHIO VALLEY. IF ANYTHING...EARLY NEXT WEEK WILL BRING BACK THE PATTERN FELT OVER MUCH OF THIS PAST WINTER. TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW AVERAGE MONDAY AND TUESDAY BEFORE MODERATING BY MID-WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 317 PM EDT TUE APR 8 2014 VFR CONDITIONS SHOULD BE THE RULE THRU THIS FCST PERIOD. WARM ADVECTION AHEAD OF FRONTAL SYSTEM MOVING THROUGH THE NORTHERN PLAINS WILL BRING AN INCREASE IN MID-HIGH CLOUDS ON WEDNESDAY. ALSO THE TIGHTENING SW GRAD AHEAD OF THE FRONT WILL ALSO CAUSE SW WINDS TO GUST BTWN 20-25 KT BY LATE WED MORNING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 442 PM EDT TUE APR 8 2014 WINDS WILL DIMINISH TONIGHT AS THE HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEP LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. WINDS WILL REACH THE 20-30KT RANGE...AND NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS WILL REACH GALE FORCE AT SOME POINT WED/THU. STABLE LOW-LEVEL TEMP PROFILE WILL WORK AGAINST STRONGER WINDS...BUT HEALTHY PRES FALLS AHEAD OF LOW LATE WED AND HEALTHY PRES RISES ARRIVING BEHIND TROF PASSAGE WED NIGHT/THU MORNING MAY BE WHAT PUSHES WINDS TO GALE FORCE FOR A TIME. WINDS WILL THEN DIMINISH THU NIGHT/FRI. INCREASING WINDS ARE EXPECTED FOR THE WEEKEND AS LOW PRES TROF APPROACHES AND THEN MOVES ACROSS THE AREA. && .HYDROLOGY... ISSUED AT 442 PM EDT TUE APR 8 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN/CENTRAL UPPER MICHIGAN HAS RIPENED. LOWS WELL BELOW FREEZING TONIGHT WILL LEAD TO REDUCED SNOWMELT OVER THE NEXT 24 HOURS...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. THE MOST ABUNDANT SNOWMELT IS EXPECTED WEDNESDAY INTO THURSDAY AS TEMPERATURES WILL REMAIN WELL ABOVE FREEZING WEDNESDAY NIGHT ALONG WITH DEWPOINTS ABOVE 32F AND BREEZY CONDITIONS. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS THROUGH THE MIDDLE OF THE WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...KLUBER AVIATION...VOSS MARINE...VOSS HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
321 PM EDT TUE APR 8 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 505 AM EDT TUE APR 8 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A RIDGE OVER WRN NAMERICA AND A TROF EXTENDING FROM HUDSON BAY TO THE WRN GULF OF MEXICO. STRONG SHORTWAVE THAT WAS OVER THE SRN PLAINS 24HRS AGO IS NOW MOVING THRU THE LOWER GREAT LAKES. CLOSER TO HOME...SHORTWAVE OVER WRN UPPER MI HAS BEEN GENERATING PESKY -SHRA FROM ISLE ROYALE ACROSS THE KEWEENAW PENINSULA DURING THE NIGHT. THE -SHRA ARE DRIFTING SSE INTO PORTIONS OF CNTRL UPPER MI ATTM. MID CLOUDS ASSOCIATED WITH SHORTWAVE HAVE WORKED TO LIMIT FOG. OVER THE NEXT SEVERAL HRS...UTILIZED MOSTLY EXTRAPOLATION/TRENDS TO SHIFT AN AREA OF ISOLD/SCT -SHRA SSE FROM THE KEWEENAW TOWARD SCNTRL UPPER MI BEFORE THE -SHRA DISSIPATE. WHERE THE -SHRA ARE OCCURRING...TEMPS WILL STAY ABOVE FREEZING. IN THE WAKE OF THE -SHRA...THERE IS STILL AN OPPORTUNITY FOR -DZ/-FZDZ TO DEVELOP THIS MORNING. BEST CHC SHOULD BE OVER WRN UPPER MI. DWPT AT DISW4 IS STILL AROUND 35F. AS THIS HIGHER DWPT AIR OVER THE LAKE ADVECTS SSE INTO WRN UPPER MI WHERE SFC TEMPS ARE AT OR BLO FREEZING...STRATUS/FOG AND POTENTIALLY -FZDZ SHOULD DEVELOP. THEREAFTER...EXPECT INCREASING SUNSHINE DURING THE AFTN AS DRIER AIR ARRIVES...BREAKING UP CLOUD COVER. IT WILL BE A COOLER DAY...ESPECIALLY NEAR LAKE SUPERIOR. OVER THE E WHERE THERE WILL BE A BRISK WIND ACROSS THE LAKE...TEMPS SHOULD HOLD MOSTLY IN THE LWR 30S TODAY. OTHERWISE...EXPECT GENERALLY 30S AND LWR 40S N TO AROUND 50 FAR SCNTRL FROM KIMT TO NEAR KMNM. SFC HIGH PRES RIDGE SHIFTS ACROSS THE UPPER LAKES TONIGHT... PROVIDING LIGHT/CALM WINDS FOR A GOOD PORTION OF THE NIGHT IN MOST AREAS. ON THE BACKSIDE OF THE RIDGE AND IN ADVANCE OF SHORTWAVE MOVING ACROSS THE SRN CANADIAN ROCKIES...STRENGTHENING WAA/ISENTROPIC ASCENT PATTERN TO THE NW WILL GENERATE SOME PCPN ACROSS MANITOBA INTO NRN ONTARIO TONIGHT. ALTHOUGH HIGH/MID CLOUDS WILL SPREAD SE INTO THE AREA OVERNIGHT...THERE SHOULD BE A LONG ENOUGH PERIOD OF MOSTLY CLEAR SKIES TO ALLOW A DECENT TEMP FALL. LOWERED MINS TOWARD THE LOW END OF AVBL GUIDANCE...REPRESENTED BY THE BIAS CORRECTED REGIONAL AND GLOBAL GEM. TRADITIONAL INTERIOR COLD SPOTS SHOULD FALL TO THE MID TEENS AND PERHAPS EVEN TO THE LOW TEENS OVER THE E. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 416 AM EDT TUE APR 8 2014 AFTER A COOLER DAY TODAY...WEDNESDAY WILL TRANSITION BACK TO THE ABOVE NORMAL TEMPERATURES SEEN OVER THE LAST COUPLE OF DAYS. THIS IS DUE TO AN UPPER RIDGE CURRENTLY OVER THE WESTERN CONUS SHIFTING EAST INTO THE GREAT LAKES REGION FOR WEDNESDAY AND WEDNESDAY NIGHT. AS THIS RIDGE MOVES IN...EXPECT A STRONG AREA OF WARM AIR ADVECTION AND Q-VECTOR CONVERGENCE SHIFTING EAST-SOUTHEAST ALONG THE US/CANADIAN BORDER (AND ACROSS THE NORTHERN HALF OF THE CWA) LATE TONIGHT THROUGH EARLY WEDNESDAY AFTERNOON. FOR MUCH OF THE LAND CWA...WOULD EXPECT THERE TO JUST BE SOME PASSING MID CLOUDS. BUT THERE MAY BE ENOUGH MOISTENING IN THE LOWER LEVELS TO ALLOW SOME LIGHT SPRINKLES TO AFFECT THE KEWEENAW PENINSULA. OTHERWISE...THIS AREA OF FORCING WILL QUICKLY SHIFT THROUGH AND SHOULD LEAD TO A FILTERED SUNSHINE OVER THE AREA DUE TO HIGH CLOUDS AHEAD OF THE NEXT SYSTEM. STRONG WARMING IN THE LOWER LEVELS THROUGH THE DAY ON WEDNESDAY (850MB TEMPS RISING FROM -4C AT 06Z TO AT LEAST 6C AT 00Z THURSDAY) SHOULD LEAD TO ANOTHER WARM DAY ACROSS THE CWA. WILL CONTINUE TO SHOW HIGHS IN THE UPPER 50S AND LOWER 60S OVER THE WESTERN HALF OF THE CWA AND LOWER VALUES (40S) OVER THE EAST WITH THE SOUTHWEST WINDS OFF LAKE MICHIGAN. SPEAKING OF THOSE WINDS...THEY LOOK TO BE A LITTLE GUSTY IN THE AFTERNOON (15-25KTS) AND THAT WILL ALLOW THE DOWNSLOPE AREAS TO WARM AND LIMIT LAKE BREEZE COOLING. WHILE THE WARMING IS OCCURRING ON WEDNESDAY...A SURFACE LOW WILL BE SHIFTING EAST THROUGH FAR NORTHERN ONTARIO AND A COLD FRONT WILL STRETCH SOUTHWEST INTO THE UPPER MISSISSIPPI VALLEY. MODELS REMAIN CONSISTENT ON THE TIMING OF THIS COLD FRONT MOVING THROUGH THE CWA DURING THE OVERNIGHT HOURS WEDNESDAY NIGHT AND FOR THE FIRST PART OF THURSDAY MORNING. MODELS ARE INDICATING THE BEST FORCING ALONG THE FRONT TO DIVE TO THE SOUTHEAST THROUGH WISCONSIN...BUT WILL HOLD ONTO CHANCE POPS DUE TO THE EXPECTED EASTWARD MOVEMENT OF THE UPSTREAM SHOWERS. STEEP MID LEVEL LAPSE RATES AND SHOWALTER VALUES AROUND 0 COULD PRODUCE A RUMBLE OF THUNDER OVER WESTERN LAKE SUPERIOR AND HAVE ADDED A SLIGHT CHANCE TO THE FAR WEST. WITH THE SHORTWAVE WELL BEHIND THE FRONT AND ONLY A VERY THIN LINE OF MOISTURE...EXPECT QPF AMOUNTS TO STAY BELOW 0.15IN IN MOST LOCATIONS. MOST OF THESE SHOWERS SHOULD SHIFT OUT OF THE CWA BY THE AFTERNOON. TEMPERATURES ALOFT COOL SOME BEHIND THE FRONT...BUT STILL LOOK TO BE AROUND 0C TO -2C AT 850MB. THOSE TEMPS COMBINED WITH SUNSHINE BEHIND THE FRONT WILL YIELD HIGHS IN THE UPPER 40S TO MID 50S. WITH A HIGH PRESSURE RIDGE SLIDING THROUGH THE AREA ON THURSDAY NIGHT...DRY CONDITIONS ARE EXPECTED AND TEMPS FALLING INTO THE UPPER 20S AND LOWER 30S. FRIDAY LOOKS TO BE DRY OVER MUCH OF THE CWA...BUT THERE ARE A COUPLE SUBTLE FEATURES TO NOTE. FIRST...A SECONDARY SURFACE TROUGH TRIES TO BRUSH THE NORTHEAST THIRD OF THE CWA FRIDAY MORNING...BUT IT DOESN/T LOOK LIKE IT WILL MAKE IT THAT FAR INTO LAKE SUPERIOR. SECOND...A WEAK SHORTWAVE AND ASSOCIATED SURFACE TROUGH LOOKS TO SHIFT EAST THROUGH UPPER MICHIGAN AND WISCONSIN FRIDAY AFTERNOON/ EVENING AND COULD KICK OFF A SHOWER OR TWO. GFS IS BY FAR THE STRONGEST WITH THE WAVE BUT MOISTURE SEEMS TO BE VERY LIMITED. WILL TREND POPS UP TO LOW END SLIGHT CHANCES FOR THE AFTERNOON/EVENING...BUT CONFIDENCE IS LOW. FOR THE WEEKEND...FOCUS IS ON TWO UPPER LEVEL FEATURES THAT WILL BE OVER THE WESTERN CONUS ON FRIDAY NIGHT...ONE NEAR SOUTHERN CALIFORNIA AND THE OTHER IN THE PACIFIC NORTHWEST. THE LEADING PIECES OF ENERGY ASSOCIATED WITH THESE WAVES WILL PUSH THE FIRST WAVE OF PRECIP ACROSS THE AREA ON SATURDAY. THIS PRECIP WILL BE ASSOCIATED WITH AN ELONGATED TROUGH STRETCHING NORTHEAST FROM THE CENTRAL/SOUTHERN ROCKIES. MODELS STILL SHOWING A WIDE VARIETY OF SOLUTIONS FOR THE LOCATION OF THE TROUGH WITH THE GFS/GEM FAST/SE ECMWF FARTHEST NORTHWEST. A GENERAL BLEND WILL WORK WELL AT THIS POINT FOR POPS (CHANCES)...MOVING INTO THE WESTERN CWA SATURDAY MORNING AND SHIFTING EAST OVER THE REST OF THE AREA IN THE AFTERNOON. THE LOCATION OF THE ELONGATED TROUGH HAS A INFLUENCE ON THE WEATHER FOR THE REGION FOR THE SECOND HALF OF THE WEEKEND AND INTO MONDAY. BY THAT POINT...THE TWO WAVES THAT ARE ALONG THE WEST COAST WILL HAVE MERGED OVER THE CENTRAL CONUS AND WILL BE SHIFTING EAST. THESE FEATURES WILL BE HELPED BY A THIRD DISTURBANCE THAT WILL DROP SOUTHEAST FROM CANADA. THE TIMING OF THESE THREE FEATURES AND HOW FAR EAST THEY END UP WILL DETERMINE PRECIP CHANCES (AND MEASURABLE SNOW POSSIBILITY) FOR PARTS OF THE CWA. AS HAS BEEN THE CASE FOR THE LAST COUPLE DAYS...THE GFS IS THE FARTHEST EAST AND THE ECMWF IS THE FARTHEST WEST WHILE THE 00Z GEM IS NOW SIMILAR TO . THE GFS. WITH THE PHASING OF SEVERAL SHORTWAVES...CONFIDENCE IN ANY ONE SOLUTION IS VERY LOW AND MODELS WILL BE HIGHLY VARIABLE OVER THE NEXT COUPLE DAYS. AT THIS POINT...WILL HAVE THE HIGHER CHANCE POPS OVER THE SOUTHEAST HALF OF THE CWA...WHERE A GENERAL CONSENSUS WOULD INDICATE PRECIP. WITH THE EXPECTED COLD AIR THAT WILL SPILL IN BEHIND THE TROUGH ON SUNDAY...WOULD EXPECT THE PRECIP TO TRANSITION TO SNOW AND THERE COULD BE SOME ACCUMULATION IF THE 12Z ECMWF IS CORRECT. IN ADDITION...THE LOW LEVEL COLD AIR SURGING IN AT THE SURFACE WITH THE NORTHERLY WINDS COULD PRODUCE A 6HR PERIOD OF FREEZING RAIN. WAY TO FAR OUT TO GET TOO EXCITED AT THAT POTENTIAL AT THIS POINT...BUT IT IS SOMETHING TO WATCH. THE FIRST HALF OF NEXT WEEK LOOKS TO BE BELOW NORMAL TEMPERATURE WISE ACROSS THE GREAT LAKES REGION...AS THE UPPER LEVEL PATTERN RESEMBLES THE ONE FROM MUCH OF THIS PAST WINTER. 850MB TEMPS DO LOOK TO FALL TOWARD -12C TO -17C FOR A SHORT PERIOD DURING THE FIRST HALF OF THE WORK WEEK AND THAT COULD LEAD TO HIGHS AROUND FEEZING ON TUESDAY. FOR THOSE THAT HAVE BEEN ENJOYING THE SPRING LIKE TEMPERATURES OVER THE LAST COUPLE OF DAYS...IT APPEARS THIS TROUGH WILL LIFT OUT OF THE AREA ON WEDNESDAY AND RETURN THE AREA BACK TO NORMAL TEMPERATURES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 317 PM EDT TUE APR 8 2014 VFR CONDITIONS SHOULD BE THE RULE THRU THIS FCST PERIOD. WARM ADVECTION AHEAD OF FRONTAL SYSTEM MOVING THROUGH THE NORTHERN PLAINS WILL BRING AN INCREASE IN MID-HIGH CLOUDS ON WEDNESDAY. ALSO THE TIGHTENING SW GRAD AHEAD OF THE FRONT WILL ALSO CAUSE SW WINDS TO GUST BTWN 20-25 KT BY LATE WED MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 505 AM EDT TUE APR 8 2014 AS PRES GRADIENT TIGHTENS BTWN APPROACHING HIGH PRES RIDGE AND DEEPENING LOW PRES MOVING FROM THE LWR LAKES TO NEW ENGLAND...WINDS WILL PICK UP ACROSS LAKE SUPERIOR THIS MORNING...BUT MAINLY OVER THE ERN PORTION OF THE LAKE WHERE WINDS SHOULD INCREASE TO 15-25KT. WINDS WILL DIMINISH TONIGHT AS THE HIGH PRES RIDGE MOVES ACROSS THE AREA. WINDS WILL THEN INCREASE WED/THU AS DEEP LOW PRES MOVES FROM MANITOBA ACROSS NRN ONTARIO TO QUEBEC. WINDS WILL REACH THE 20-30KT RANGE...AND NOT OUT OF THE QUESTION THAT WIND GUSTS AT HIGH PLATFORMS WILL REACH GALE FORCE AT SOME POINT WED/THU. STABLE LOW-LEVEL TEMP PROFILE WILL WORK AGAINST STRONGER WINDS...BUT HEALTHY PRES FALLS AHEAD OF LOW WED AND HEALTHY PRES RISES ARRIVING BEHIND TROF PASSAGE WED NIGHT/THU MORNING MAY BE WHAT PUSHES WINDS TO GALE FORCE FOR A TIME. WINDS WILL THEN DIMINISH THU NIGHT/FRI. INCREASING WINDS ARE EXPECTED FOR THE WEEKEND AS LOW PRES TROF APPROACHES AND THEN MOVES ACROSS THE AREA. && .HYDROLOGY... ISSUED AT 416 AM EDT TUE APR 8 2014 THE FORECASTED ABOVE NORMAL TEMPERATURES FOR MUCH OF THIS WEEK WILL LEAD TO INCREASING SNOWMELT AND RISING RIVER LEVELS. MODELED SNOWPACK TEMPERATURES FROM NOHRSC INDICATES A GOOD PORTION OF THE SNOWPACK IN WESTERN UPPER MICHIGAN HAS RIPENED AND WOULD EXPECT THE ABOVE NORMAL TEMPERATURES TODAY TO INCREASE SNOWMELT. COOLER TEMPERATURES ARRIVING ON TUESDAY (INCLUDING LOWS WELL BELOW FREEZING TUESDAY NIGHT) WILL LEAD TO REDUCED SNOWMELT DURING THAT PERIOD...BUT TEMPERATURES WILL RISE TO ABOVE NORMAL VALUES FOR WEDNESDAY THROUGH SATURDAY. THIS EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES...WITH SEVERAL NIGHTS AT OR ABOVE FREEZING...SHOULD LEAD TO A STEADY SNOWMELT INTO THE FIRST HALF OF THE WEEKEND. PRECIPITATION SHOULD BE LIGHT FOR MOST LOCATIONS THIS WEEK...WITH THE BEST CHANCE FOR RAIN COMING LATE WEDNESDAY NIGHT INTO THURSDAY MORNING (AMOUNTS LESS THAN 0.15IN). WITH THE FORECASTED CONDITIONS...WOULD EXPECT ONLY LIMITED RISES TO THE AREA RIVERS OVER THE FIRST HALF OF THIS WORK WEEK. THEN AS THE TEMPERATURES STAY ABOVE FREEZING FROM WEDNESDAY MORNING THROUGH LATE THURSDAY NIGHT...SNOWMELT WILL INCREASE AND LEAD TO PERSISTENT RISING OF RIVER LEVELS ACROSS THE CWA INTO THE UPCOMING WEEKEND. UNLESS ICE JAMS ARE EXPERIENCED...RIVER LEVELS ARE EXPECTED TO REMAIN BELOW BANKFULL THROUGH THIS WORK WEEK. PERSONS PLANNING RECREATION NEAR RIVERS FOR THE END OF THIS WORK WEEK AND THE UPCOMING WEEKEND SHOULD PREPARE FOR RISING RIVER LEVELS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...SRF AVIATION...VOSS MARINE...ROLFSON HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
140 PM EDT TUE APR 8 2014 .SYNOPSIS...A COLD FRONT WILL PUSH EAST ACROSS CENTRAL NC THIS AFTERNOON. AN UPPER LEVEL TROUGH WILL APPROACH THE AREA TONIGHT AND SWING THROUGH THE AREA LATE WEDNESDAY. HIGH PRESSURE CENTERED OVER THE GULF OF MEXICO AND THE SOUTH ATLANTIC WILL EXTEND INTO THE REGION ON THURSDAY AND FRIDAY. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 1105 AM TUESDAY... AT 1100 AM THE SURFACE COLD FRONT WAS ANALYZED FROM JUST WEST OF ROANOKE RAPIDS TO RALEIGH TO NEAR WADESBORO. MUCH DRIER AIR IS SPILLING INTO THE REGION BEHIND THE FRONT WITH DEWPOINTS DOWN INTO THE LOWER 40S ACROSS THE TRIAD WHILE AHEAD OF THE FRONT...DEW POINTS ARE IN THE MID 60S ACROSS THE SOUTHERN COASTAL PLAIN. EVEN WITH MOIST DEW POINTS...INSTABILITY IS RATHER LACKING BASED ON THE MOST RECENT SPC MESOANALYSIS. RECENT RADAR IMAGERY SHOWS A FEW SHOWERS DEVELOPING AHEAD OF THE FRONT ACROSS JOHNSTON AND WILSON COUNTIES WITH LIGHT TO MODERATE RETURNS. RECENT HRRR RUNS NOTED THE POTENTIAL FOR THESE SHOWERS BUT INDICATED A LIMITED AERIAL OVERAGE AND INTENSITY. SATELLITE IMAGERY AND SURFACE OBSERVATIONS NOTE A DECREASE IN THE LOW LEVEL MOISTURE AND CLOUDS BEHIND THE COLD FRONT WITH A FAIRLY THICK VEIL OF HIGH LEVEL CLOUDS ASSOCIATED WITH A STOUT 165+KT JET ALOFT. THE PRIO MORNING UPDATE TRIMMED POPS DOWN TO JUST THE SOUTHEAST PORTION OF THE CAW FOR THIS MORNING AND MADE ADJUSTMENTS TO CLOUD AND TEMPERATURE TRENDS. TEMPERATURE FORECASTS FOR THIS AFTERNOON WILL BE PROBLEMATIC WITH THE COUNTERACTIVE INFLUENCES OF INCREASING SUNSHINE AND SOME SLIGHT COLD ADVECTION. LEANED HEAVILY UPON THE HRRR HOURLY TEMPERATURE GUIDANCE WHICH RESULTED IN MAX TEMPERATURES IN THE MID TO UPPER 60S IN THE TRIAGE AND THE LOWER 70S ELSEWHERE. -BLAES TONIGHT AND WEDNESDAY: EXPECT A SERIES OF EMBEDDED S/W`S IN THE DEEP TROUGH ALOFT WILL CROSS THE REGION AS THE DEEP TROUGH ITSELF SHIFTS EASTWARD AND ACROSS THE AREA THROUGH WEDNESDAY. THIS WILL RESULT IN PERIODS OF PARTLY TO MOSTLY CLOUDY/CLOUDY SKIES. EXPECT WE WILL GENERALLY REMAIN DRY THOUGH. HOWEVER... WITH 500 MB HEIGHTS FALLING SOME 150 METERS BETWEEN NOW AND WEDNESDAY MORNING WE WILL SEE OUR INSTABILITY ALOFT INCREASE... WITH POSSIBLY SOME SHOWERS DEVELOPING WEDNESDAY AFTERNOON IN ASSOCIATION WITH THE FINAL PASSING SHORTWAVE. FOR NOW WILL LEAVE POPS IN THE SLIGHT CHANCE CATEGORY AS MODEL SOUNDING ARE QUITE DRY AND MODEL GUIDANCE HAS TRENDED DRIER. EXPECT LOWS WEDNESDAY MORNING WILL GENERALLY BE IN THE 40S... WITH HIGHS WEDNESDAY AFTERNOON IN THE 60S. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 315 AM TUESDAY... WEDNESDAY NIGHT AND THURSDAY... A S/W RIDGE IN THE MID-UPPER LEVELS AND ITS ATTENDANT SFC HIGH WILL CROSS CENTRAL NC WEDNESDAY NIGHT INTO THURSDAY. THIS WEATHER SYSTEM WILL PROVIDE PLENTY OF DRY STABLE AIR LEADING TO CLEAR SKIES WEDNESDAY NIGHT AND INTO THURSDAY. SFC WINDS WILL DECOUPLE EARLY WEDNESDAY EVENING...ALLOWING TEMPS TO COOL QUICKLY. LATEST MOS GUIDANCE HAS COME IN A COUPLE OF DEGREES WARMER THAN PREVIOUS RUN. NOT READY TO BUY INTO THIS YET AS SFC DEWPOINTS UNDERNEATH THE HIGH AT THIS TIME ARE IN THE 20S TO LOWER 30S. WENT WITH MIN TEMPS UPPER 30S NORTH-NW TO LOWER 40S SOUTH. POTENTIAL FOR LIGHT FROST DOES NOT LOOK AS GOOD AS IT DID 24-48 HOURS AGO. HOWEVER STILL BELIEVE THAT A SPOT OR TWO ACROSS THE NORTHERN PIEDMONT MAY DIP BRIEFLY INTO THE MID 30S TO ALLOW FROST FORMATION BUT LIMITED NATURE OF THE LIGHT FROST SUGGEST THAT AN ADVISORY WOULD PROBABLY BE OVERKILL. SFC HIGH WILL SCOOT QUICKLY EAST THURSDAY WITH A WARM BREEZY SW SFC WIND DEVELOPING IN ITS WAKE. THIS LOW LEVEL FLOW WILL ADVECT WARMER AIR INTO CENTRAL NC. AGAIN...MOS GUIDANCE HAS TRENDED WARMER COMPARED TO PREVIOUS RUNS. PREFER TO WAIT TO SEE IF THIS TREND HOLDS AS MODEL LOW LEVEL THICKNESSES SUPPORT MAX TEMPS 3-5 DEGREES COOLER. FOR NOW WILL FAVOR MAX TEMPS ON THE COOL END OF MOS GUIDANCE... VARYING FROM NEAR 70 ACROSS THE NORTH TO THE LOWER 70S SOUTH. THURSDAY NIGHT AND FRIDAY...WARM AND DRY CONDITIONS WILL PERSIST AS FLOW ALOFT WILL REMAIN ZONAL AND LOW LEVEL SW FLOW CONTINUES WITH A SFC HIGH ANCHORED OFF THE SE U.S. COAST. THE MODIFYING AIR MASS WILL SUPPORT MIN TEMPS THURSDAY NIGHT ABOUT 10 DEGREES WARMER THAN THE PREVIOUS NIGHT (UPPER 40S TO AROUND 50). MAX TEMPS FRIDAY AFTERNOON REBOUND WELL INTO THE 70S...APPROACHING 80 IN THE FAR SOUTH-SE. && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AS OF 315 AM TUESDAY... FRIDAY NIGHT AND SATURDAY...A S/W IN THE NORTHERN STREAM WILL CROSS THE GREAT LAKES AND NEW ENGLAND. THIS FEATURE WILL DRAG A SFC COLD FRONT TOWARD CENTRAL NC BY LATE FRIDAY AND FRIDAY NIGHT...CROSSING INTO OUR REGION EARLY SATURDAY BEFORE DISSIPATING. BEST/DEEPEST MOISTURE AND BETTER LIFT WILL OCCUR WELL TO OUR NORTH-NORTHWEST. THE FRONT LOSES A LOT OF ITS UPPER SUPPORT BY THE TIME IT REACHES CENTRAL NC LATE FRIDAY NIGHT INTO EARLY SATURDAY. IN ADDITION...MOISTURE WILL BE FAIRLY LIMITED. PLAN TO MAINTAIN A SLIGHT CHANCE POP ACROSS THE FAR NORTH FRIDAY NIGHT AND A SLIGHT CHANCE POP MOST PLACES SATURDAY THOUGH IT APPEARS THAT S/W RIDGING ALOFT WILL TAKE HOLD BY SATURDAY AFTERNOON. SUBSIDENCE ASSOCIATED WITH THIS FEATURE SHOULD LIMIT SHOWER DEVELOPMENT. ADDITIONAL CLOUD COVER FRIDAY NIGHT AND A LIGHT SOUTH WIND WILL RESULT IN MILD OVERNIGHT CONDITIONS. A MIX OF CLOUDS AND SUN SATURDAY AND VERY LITTLE CHANGE IN THE AIR MASS SUPPORTS MAX TEMPS IN THE MID-UPPER 70S. SUNDAY INTO MONDAY...UPPER LEVEL FLOW WILL GRADUALLY BACK TO THE SW IN ADVANCE OF A DEVELOPING/STRENGTHENING L/W TROUGH THAT WILL APPROACH FROM THE WEST. A S/W RIDGE OVER SE U.S. SUNDAY WILL MAINTAIN WARM AND MOSTLY DRY CONDITIONS. CANNOT RULE OUT AN ISOLATED SHOWER LATE SUNDAY AFTERNOON AS NEAR SFC FLOW BECOMES SELY...LEADING TO A WEAK UPSLOPE COMPONENT AND SOME MOISTURE ADVECTION OFF THE ATLANTIC. SHOWER THREAT APPEARS TOO MINIMAL TO MENTION IN FORECAST AT THIS TIME. SHOWER THREAT WILL GRADUALLY INCREASE MONDAY AS DEEP/STRENGTHENING SLY FLOW WILL ADVECT GULF MOISTURE INTO CENTRAL NC. THIS MOIST AND SLIGHTLY UNSTABLE AIR MASS MAY SUPPORT A FEW SHOWERS BY MONDAY AFTERNOON DUE TO SFC HEATING. BETTER DYNAMICS/SUPPORT ALOFT WILL OCCUR MONDAY NIGHT INTO TUESDAY FOR A GREATER THREAT FOR SHOWERS. TEMPS SUNDAY AND MONDAY EXPECTED TO REMAIN MILD WITH MAX TEMPS AVERAGING 5-6 DEGREES ABOVE NORMAL. EXPECT MIN TEMPS IN THE 50S WITH AFTERNOON TEMPS IN THE 75-80 DEGREE RANGE. && .AVIATION /18Z TUESDAY THROUGH SATURDAY/... AS OF 140 PM TUESDAY... 24 HOUR TAF PERIOD...A COLD FRONT CONTINUES TO MOVE SLOWLY EAST ACROSS CENTRAL NC THIS AFTERNOON. IT SHOULD PUSH EAST OF KFAY AND KGSB BY 19Z. A NORTHWEST FLOW OF DRIER AIR AT LOW LEVELS WILL CONTINUE TO SPREAD ACROSS CENTRAL NC BEHIND THE FRONT. CIGS AND VISIBILITIES ARE NOW VFR AT ALL TAF LOCATIONS AND NEARLY ALL OF CENTRAL NC WITH THE EXCEPTION OF SOME LINGERING MVFR CIGS IN THE COASTAL PLAIN AT LOCATIONS SUCH AS GSB AND ETC. WHILE VFR CONDITIONS ARE EXPECTED TO DOMINATE THE WEATHER THROUGH THE 24 HOUR TAF PERIOD...AN UPPER LEVEL TROUGH WILL APPROACH THE REGION TONIGHT AND MOVE THROUGH THE AREA ON WEDNESDAY PRODUCING WIDESPREAD CEILINGS AROUND 4-6KFT TONIGHT AND WEDNESDAY. SOME RAIN SHOWERS WHICH COULD RESULT IN A BRIEF PERIOD OF LOWER CIGS AND VSBYS...WHICH MAY FLIRT WITH MVFR CRITERIA ARE POSSIBLE DURING THE PERIOD...ESPECIALLY OVERNIGHT AND AGAIN REDEVELOPING WEDNESDAY AFTERNOON. CONFIDENCE IS STILL LOW AND THE COVERAGE SHOULD BE LIMITED SO HAVE OMITTED IT FROM THE TAFS FOR NOW. OTHERWISE...A GENERAL NORTHWEST TO NORTHERLY FLOW AT 10 KTS OR LESS IS EXPECTED THROUGH THE NEXT 24 HOURS. OUTLOOK....AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS CENTRAL NC WEDNESDAY TRIGGERING A FEW SHOWERS AND WITH PERHAPS A BRIEF PERIOD OF MVFR CEILINGS OR VISIBILITIES. HIGH PRESSURE OFF THE SOUTHEAST COAST WIL PRODUCE A SOUTHWESTERLY FLOW AND PROLONGED PERIOD OF FAIR WEATHER DURING THE REMAINDER OF THE PERIOD. -BLAES && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BLAES NEAR TERM...BLAES/BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...BLAES
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1243 PM CDT TUE APR 8 2014 .UPDATE... 18Z TAF DISCUSSION. && .AVIATION... VFR CIGS WITH -SHRA/-TSRA EXPECTED AROUND ALL AIRPORTS THIS AFTERNOON/EARLY EVENING AS UPPER TROUGH MOVES ACROSS THE REGION. STRONGER CONVECTION COULD CONTAIN HAIL AND GUSTY WINDS. ACTIVITY TO DIMINISH IN THE EVENING WITH MVFR VIS/CIGS DEVELOPING OVERNIGHT DUE TO WET GROUNDS/LOW LEVEL MOISTURE. LIGHT WEST TO NORTHWEST WINDS ANTICIPATED THROUGHOUT THE TAF PERIOD. SHAMBURGER && .PREV DISCUSSION... /ISSUED 1103 AM CDT TUE APR 8 2014/ UPDATE... SURFACE OBSERVATIONS AND VISIBLE SATELLITE IMAGERY THIS MORNING SHOWS CLOUD COVER KEEPING TEMPERATURES DOWN A BIT WITH CURRENT READINGS IN THE UPPER 40S TO MID 50S. WENT AHEAD AND ADJUSTED HIGHS BASED ON CURRENT TRENDS AND WIDESPREAD CLOUD COVER...BUT BREAKS IN THE CLOUDS SHOULD STILL ALLOW FOR HIGHS IN THE UPPER 50S TO MID 60S. WATER VAPOR IMAGERY THIS MORNING SHOWS CORE OF UPPER TROUGH APPROACHING THE MID STATE FROM THE WEST. 12Z RAOBS SHOW UNUSUALLY COLD MID LEVEL TEMPERATURES ASSOCIATED WITH THIS TROUGH WITH 500MB TEMPERATURES RANGING FROM -25C TO -30C. DESPITE HIGHS ONLY IN THE 50S AND 60S...WARMING BL COMBINED WITH THE COLD MID LEVELS WILL MAKE FOR AN UNSTABLE ATMOSPHERE BY AFTERNOON WITH CAPE VALUES PROGGED BY FORECAST SOUNDINGS AS HIGH AS 800 J/KG IN WESTERN ZONES. THUS EXPECT SCATTERED TO NUMEROUS SHOWERS AND EVEN A FEW THUNDERSTORMS TO BREAK OUT...AND EXPANDED LIKELY POPS TO ALL ZONES IN LINE WITH LATEST HRRR RUNS. THE COLD MID LEVEL TEMPERATURES COMBINED WITH VERY LOW WET BULB ZERO HEIGHTS AROUND 5000 FT AGL INDICATE ANY OF THE STRONGER CONVECTION WILL BE CAPABLE OF PRODUCING HAIL THIS AFTERNOON...WITH THE GREATEST RISK FOR HAIL IN OUR WESTERN AND SOUTHWESTERN COUNTIES WHERE INSTABILITY WILL BE HIGHEST. HAIL SIZE EXPECTED TO BE MAINLY SUB- SEVERE BUT CANNOT RULE OUT SOME MARGINAL SEVERE HAIL IN THE STRONGER CORES. SHAMBURGER PREV DISCUSSION... /ISSUED 556 AM CDT TUE APR 8 2014/ UPDATE...FOR 12Z TAFS. AVIATION... UPPER TROUGH EXPECTED TO MOVE ACROSS THE REGION NEXT 24 HOURS. CONDITIONS ARE EXPECTED TO REMAIN LARGELY VFR BUT SCATTERED CONVECTION BETWEEN ROUGHLY 19Z-02Z MAY BRIEFLY REDUCE CIGS/VSBYS. MVFR FOG LIKELY TO DEVELOP OVERNIGHT. PREV DISCUSSION... /ISSUED 337 AM CDT TUE APR 8 2014/ DISCUSSION... THIS MORNING...A SERIES OF SHORTWAVES EXISTS WITHIN A DEVELOPING UPPER TROUGH UPSTREAM. MOISTURE IN ASSOCIATION WITH THESE SHORTWAVES IS RATHER DEEP AND SOME LIGHT SHOWER ACTIVITY IS ONGOING ACROSS MO AND AR. LATER TODAY...THE UPPER TROUGH WILL MOVE EASTWARD AND WILL BE ORIENTED OVER THE MID STATE BY LATE AFTERNOON. SHORTWAVE IMPULSES WILL CONTINUE TO RESIDE WITHIN THE TROUGH ALONG WITH FAIRLY DEEP MOISTURE LEVELS. THEREFORE...FOR THE FCST...CLOUDS WILL BE ON THE INCREASE TODAY WITH SHOWERS DEVELOPING BY LATE IN THE DAY. LATEST HRRR SHOWS A MOSTLY DRY MORNING BUT BY THIS AFTERNOON...CONVECTIVE TEMPS WILL BE REACHED AND SHOWERS WILL DEVELOP. LAPSE RATES BY THIS AFTERNOON ARE SOMEWHAT IMPRESSIVE. MID LEVEL THETA E RIDGING DOES EXIST BUT PRIMARILY WEST AND SOUTHWEST OF THE MID STATE. SFC CAPES AND INSTABILITIES WILL BE IN PLACE SO THE POTENTIAL FOR AT LEAST ISOL TSTM ACTIVITY WILL EXIST. STORMS DO NOT LOOK STRONG OR SEVERE BUT PERHAPS SOME SMALL PEA SIZE HAIL COULD OCCUR ACROSS WESTERN AREAS THIS AFTERNOON OR EVENING. AFTER A FEW LINGERING SHOWERS THIS EVENING...WE MAY SEE SOME PARTIAL CLEARING LATE. DRY WEATHER TO RETURN FOR WED AND THU. IT WILL BE QUITE A BIT WARMER ON THURSDAY AS THE TROUGHING PATTERN SHIFTS EAST AND HEIGHTS INCREASE. IN THE EXT FCST...A WEAK FRONTAL BOUNDARY WILL ATTEMPT TO SETTLE SOUTHEASTWARD TOWARD TN ON FRIDAY. WILL GO AHEAD AND KEEP THE SLIGHT CHANCE OF SHOWERS AND TSTMS GOING. THE FRONT IS NOT EXPECTED TO MOVE THROUGH HOWEVER AND WILL LIFT TO THE NORTH AS A WARM FRONT DURING THE WEEKEND. NEXT APPRECIABLE RAIN CHANCE WILL OCCUR ON SUNDAY AND MONDAY AS A STRONG FRONTAL SYSTEM MOVES THROUGH. THIS COULD BE A GOOD RAIN MAKER FOR US. AT THE SFC...THE BETTER LOWER LEVEL ENERGY MAY TAKE A SOUTHERLY ROUTE AND THUS...NOT LOOKING LIKE A WELL ORGANIZED SEVERE THREAT AT THIS TIME...JUST A GOOD RAIN MAKER...WITH A FEW NON SVR TSTMS POSSIBLE. FOR THE EXT TEMPS...ABOVE NORMAL TEMPS EXPECTED AS 850 MB VALUES WILL BE GENERALLY 10C+. A COOL DOWN WILL BE LIKELY BEHIND MONDAYS FROPA. THE 7 TO 10 DAY PERIOD LOOKS RATHER CHILLY FOR EARLY TO MID APRIL. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1103 AM CDT TUE APR 8 2014 .UPDATE... SURFACE OBSERVATIONS AND VISIBLE SATELLITE IMAGERY THIS MORNING SHOWS CLOUD COVER KEEPING TEMPERATURES DOWN A BIT WITH CURRENT READINGS IN THE UPPER 40S TO MID 50S. WENT AHEAD AND ADJUSTED HIGHS BASED ON CURRENT TRENDS AND WIDESPREAD CLOUD COVER...BUT BREAKS IN THE CLOUDS SHOULD STILL ALLOW FOR HIGHS IN THE UPPER 50S TO MID 60S. WATER VAPOR IMAGERY THIS MORNING SHOWS CORE OF UPPER TROUGH APPROACHING THE MID STATE FROM THE WEST. 12Z RAOBS SHOW UNUSUALLY COLD MID LEVEL TEMPERATURES ASSOCIATED WITH THIS TROUGH WITH 500MB TEMPERATURES RANGING FROM -25C TO -30C. DESPITE HIGHS ONLY IN THE 50S AND 60S...WARMING BL COMBINED WITH THE COLD MID LEVELS WILL MAKE FOR AN UNSTABLE ATMOSPHERE BY AFTERNOON WITH CAPE VALUES PROGGED BY FORECAST SOUNDINGS AS HIGH AS 800 J/KG IN WESTERN ZONES. THUS EXPECT SCATTERED TO NUMEROUS SHOWERS AND EVEN A FEW THUNDERSTORMS TO BREAK OUT...AND EXPANDED LIKELY POPS TO ALL ZONES IN LINE WITH LATEST HRRR RUNS. THE COLD MID LEVEL TEMPERATURES COMBINED WITH VERY LOW WET BULB ZERO HEIGHTS AROUND 5000 FT AGL INDICATE ANY OF THE STRONGER CONVECTION WILL BE CAPABLE OF PRODUCING HAIL THIS AFTERNOON...WITH THE GREATEST RISK FOR HAIL IN OUR WESTERN AND SOUTHWESTERN COUNTIES WHERE INSTABILITY WILL BE HIGHEST. HAIL SIZE EXPECTED TO BE MAINLY SUB- SEVERE BUT CANNOT RULE OUT SOME MARGINAL SEVERE HAIL IN THE STRONGER CORES. SHAMBURGER && .PREV DISCUSSION... /ISSUED 556 AM CDT TUE APR 8 2014/ UPDATE...FOR 12Z TAFS. AVIATION... UPPER TROUGH EXPECTED TO MOVE ACROSS THE REGION NEXT 24 HOURS. CONDITIONS ARE EXPECTED TO REMAIN LARGELY VFR BUT SCATTERED CONVECTION BETWEEN ROUGHLY 19Z-02Z MAY BRIEFLY REDUCE CIGS/VSBYS. MVFR FOG LIKELY TO DEVELOP OVERNIGHT. PREV DISCUSSION... /ISSUED 337 AM CDT TUE APR 8 2014/ DISCUSSION... THIS MORNING...A SERIES OF SHORTWAVES EXISTS WITHIN A DEVELOPING UPPER TROUGH UPSTREAM. MOISTURE IN ASSOCIATION WITH THESE SHORTWAVES IS RATHER DEEP AND SOME LIGHT SHOWER ACTIVITY IS ONGOING ACROSS MO AND AR. LATER TODAY...THE UPPER TROUGH WILL MOVE EASTWARD AND WILL BE ORIENTED OVER THE MID STATE BY LATE AFTERNOON. SHORTWAVE IMPULSES WILL CONTINUE TO RESIDE WITHIN THE TROUGH ALONG WITH FAIRLY DEEP MOISTURE LEVELS. THEREFORE...FOR THE FCST...CLOUDS WILL BE ON THE INCREASE TODAY WITH SHOWERS DEVELOPING BY LATE IN THE DAY. LATEST HRRR SHOWS A MOSTLY DRY MORNING BUT BY THIS AFTERNOON...CONVECTIVE TEMPS WILL BE REACHED AND SHOWERS WILL DEVELOP. LAPSE RATES BY THIS AFTERNOON ARE SOMEWHAT IMPRESSIVE. MID LEVEL THETA E RIDGING DOES EXIST BUT PRIMARILY WEST AND SOUTHWEST OF THE MID STATE. SFC CAPES AND INSTABILITIES WILL BE IN PLACE SO THE POTENTIAL FOR AT LEAST ISOL TSTM ACTIVITY WILL EXIST. STORMS DO NOT LOOK STRONG OR SEVERE BUT PERHAPS SOME SMALL PEA SIZE HAIL COULD OCCUR ACROSS WESTERN AREAS THIS AFTERNOON OR EVENING. AFTER A FEW LINGERING SHOWERS THIS EVENING...WE MAY SEE SOME PARTIAL CLEARING LATE. DRY WEATHER TO RETURN FOR WED AND THU. IT WILL BE QUITE A BIT WARMER ON THURSDAY AS THE TROUGHING PATTERN SHIFTS EAST AND HEIGHTS INCREASE. IN THE EXT FCST...A WEAK FRONTAL BOUNDARY WILL ATTEMPT TO SETTLE SOUTHEASTWARD TOWARD TN ON FRIDAY. WILL GO AHEAD AND KEEP THE SLIGHT CHANCE OF SHOWERS AND TSTMS GOING. THE FRONT IS NOT EXPECTED TO MOVE THROUGH HOWEVER AND WILL LIFT TO THE NORTH AS A WARM FRONT DURING THE WEEKEND. NEXT APPRECIABLE RAIN CHANCE WILL OCCUR ON SUNDAY AND MONDAY AS A STRONG FRONTAL SYSTEM MOVES THROUGH. THIS COULD BE A GOOD RAIN MAKER FOR US. AT THE SFC...THE BETTER LOWER LEVEL ENERGY MAY TAKE A SOUTHERLY ROUTE AND THUS...NOT LOOKING LIKE A WELL ORGANIZED SEVERE THREAT AT THIS TIME...JUST A GOOD RAIN MAKER...WITH A FEW NON SVR TSTMS POSSIBLE. FOR THE EXT TEMPS...ABOVE NORMAL TEMPS EXPECTED AS 850 MB VALUES WILL BE GENERALLY 10C+. A COOL DOWN WILL BE LIKELY BEHIND MONDAYS FROPA. THE 7 TO 10 DAY PERIOD LOOKS RATHER CHILLY FOR EARLY TO MID APRIL. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1223 PM CDT TUE APR 8 2014 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION...SURFACE HIGH PRESSURE OVER WESTERN TEXAS TO SETTLE ALONG THE TEXAS GULF COAST THIS EVENING AND TRACK EAST ON WEDNESDAY. VFR CONDITIONS TO PREVAIL TONIGHT AND WEDNESDAY WITH NORTHWEST WINDS TO DROP OFF QUICKLY AFTER SUNSET BECOMING LIGHT AND VARIABLE. && .PREV DISCUSSION... /ISSUED 1014 AM CDT TUE APR 8 2014/ DISCUSSION...UPDATED FOR LATEST MARINE AND FIRE WEATHER DISCUSSION BELOW. MARINE...MIXING OF NORTHWEST FLOW TO THE SURFACE GETTING UNDERWAY THIS MORNING BUT WINDS HOLDING IN THE 12-15 KNOT RANGE WITH FEW HIGHER GUSTS OVER THE OFFSHORE WATERS. WITH LIMITED COLD ADVECTION EVEN THOUGH 850 MB WINDS SIT ON 30-33 KNOTS AND SHOULD BE ABLE TO MIX DOWN A BIT. MOST RECENT NAM DATA IN THE 950-925 MB LAYER INDICATE 20-22 KNOTS WITH LESS TOWARD THE SURFACE...AND IT MAY BE A BIT TOUGH TO REALIZE 20 KNOT SUSTAINED ACROSS THE OFFSHORE WATERS...ESPECIALLY THE SOUTHERN LEG WHICH IS FARTHER AWAY FROM THE BETTER PRESSURE GRADIENT. FOR NOW...WILL HOLD ADVISORY/CAUTION AS IS AND MONITOR FOR POSSIBLE CANCELLATION EARLY THIS AFTERNOON. 52/BSG FIRE WEATHER...LATEST 12Z NAM AND 12Z HRRR ARE RIGHT IN TUNE WITH THE CURRENT THINKING ON 20 FOOT WINDS...WITH A LATE MORNING/EARLY AFTERNOON SURGE ACROSS THE UPPER VALLEY AND RIO GRANDE PLAINS DIMINISHING BELOW 15 MPH AS THE LOWEST RH APPROACHES. IN THE WARNING AREA...THE 15+ MPH 20 FOOT NORTHWEST WINDS LINE UP WITH THE SHARPEST DEW POINT DROP BETWEEN 1 AND 5 PM. THE BIG QUESTION WILL BE HOW LOW THE HUMIDITY FALLS...WE NEED TO DROP JUST BELOW 15 PERCENT FOR A COUPLE HOURS TO REALIZE THE `FLASH DROUGHT` SITUATION THAT CAN CAUSE RAPID WILDFIRE GROWTH AND THAT MAY BE A STRETCH BUT SITUATION IS RIGHT ON THE FENCE SO NO REASON TO REMOVE THE SAFETY VALVE OF THE WARNING FOR NOW. 52/BSG PREV DISCUSSION... /ISSUED 628 AM CDT TUE APR 8 2014/ DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. AVIATION...VFR CONDITIONS WITH CLEAR SKIES EXPECTED TODAY AS NORTHWESTERLY WINDS USHER IN MUCH DRIER AIR. WINDS WILL GUST AT 18 TO 25 KNOTS THROUGH THE LATE MORNING AND AFTERNOON. WIND SPEEDS WILL DECREASE AFTER SUNSET AND VFR CONDITIONS ARE EXPECTED TO HOLD OVERNIGHT. PREV DISCUSSION... /ISSUED 355 AM CDT TUE APR 8 2014/ SHORT TERM /NOW THROUGH WEDNESDAY/...UPPER LEVEL TROUGH AXIS IS CLEAR ON WATER VAPOR JUST TO THE NORTHWEST OF THE REGION. MOST EVIDENT AREAS OF LARGE SCALE LIFT ARE NOW EAST OF DEEP SOUTH TEXAS WITH THE RADAR BECOMING INCREASINGLY QUIET OVER THE LAST FEW HOURS. LOW LEVEL MOISTURE PERSISTS...ESPECIALLY NEAR THE COAST... AND PATCHES OF FOG MAY DEVELOP EARLY THIS MORNING IN CAMERON AND WILLACY COUNTY. TODAY...AS THE UPPER LEVEL TROUGH AXIS CLEARS TO THE EAST A REINFORCING SHOT OF NORTHWESTERLY SURFACE WINDS WILL MOVE INTO THE AREA. NAM12 AND ARW/NMM 00Z GUIDANCE PRODUCES WIND SPEEDS AROUND 15 TO 20 MPH THROUGH THE DAY WITH DEW POINTS DROPPING INTO THE LOW 30S ACROSS MOST OF THE AREA. MET AND MAV MOS DO NOT SHOW DEW POINTS THIS LOW...BUT SUSPECT THE CLIMATOLOGY SIGNAL IS TOO STRONG IN THE DATASET FOR THE ANOMALOUSLY DRY AIR AND WENT CLOSER TO THE RAW MODEL OUTPUT BASED ON THE SOURCE AIR MASS IN SOUTHEASTERN COLORADO AND NEW MEXICO WITH DEW POINTS AROUND 0 TO 10 DEGREES F IN THAT AREA. DEW POINTS WILL DROP QUICKLY A FEW HOURS AFTER SUNRISE WITH VERTICAL MIXING COMBINING WITH ADVECTION OF VERY DRY AIR. THERE WILL BE VERY WEAK NET COLD ADVECTION ONGOING BUT WITH AMPLE SUNSHINE AND INCREASING 850/700MB THICKNESS VALUES...CONTINUED A LITTLE WARMER THAN GUIDANCE ON FORECAST MAXES. PRESSURE GRADIENT SHOULD BE STRONG ENOUGH FOR 20 KNOT MARINE WINDS AND NAM/HIGH RES DEPICTION OF LOWER WINDS NEAR SHORE AND ADVISORY LEVEL WINDS OFFSHORE MAKES SENSE GIVEN SATELLITE DERIVED AND OBSERVED SEA SURFACE TEMPERATURE OBS. HAVE ISSUED A SMALL CRAFT ADVISORY FOR THE OFFSHORE ZONES AND A RED FLAG WARNING FOR ALL BUT ZAPATA AND JIM HOGG COUNTIES FOR SEVERAL HOURS OF 15 MPH 20 FOOT WIND AND AT OR BELOW 15 PERCENT RELATIVE HUMIDITY. WIND SPEEDS ARE FORECAST TO BE A LITTLE TOO LOW IN JIM HOGG AND ZAPATA COUNTY FOR A WARNING WITH THIS FORECAST PACKAGE. TONIGHT...BOUNDARY LAYER IS EXPECTED TO FULLY DECOUPLE TONIGHT AMID MOSTLY CLEAR SKIES. WINDS OFFSHORE WILL SHIFT TO THE EAST. VERY DRY NEAR SURFACE AIR AND GOOD RADIATIONAL COOLING CONDITIONS WILL LIKELY PRODUCE LOWS IN THE LOW TO MID 50S. WEDNESDAY...EASTERLY LOW LEVEL FLOW WILL BECOME MORE SOUTHEASTERLY WEDNESDAY MORNING INTO THE AFTERNOON AS SURFACE HIGH PRESSURE STRENGTHENS OVER THE NORTH CENTRAL GULF OF MEXICO. A SLOW RETURN OF LOW LEVEL MOISTURE WILL ALSO OCCUR WITH THOSE WINDS ALTHOUGH IT WILL PROBABLY TAKE A DAY OR TWO TO RECHARGE THE WESTERN GULF AIR MASS AFTER THE ONSLAUGHT OF VERY DRY CONTINENTAL AIR EXPECTED ON TUESDAY. WITH THAT...PLEASANT WEATHER IS EXPECTED ON WEDNESDAY WITH WARM TEMPERATURES IN THE MID TO UPPER 80S AND A STEADY BUT NOT OVER WHELMING SOUTHEAST BREEZE. LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...A BROAD MID LEVEL RIDGE WILL RESIDE OVER THE SOUTHWEST UNITED STATES AND WILL MAINTAIN A PERIOD OF RELATIVELY QUIET WEATHER THROUGH THE END OF THE WEEK AND EARLY PART OF THE WEEKEND. LOW RELATIVE HUMIDITY VALUES WILL REPEAT THURSDAY AFTN...DIPPING INTO THE 20S OUT WEST AND ENHANCING FIRE WEATHER CONCERNS A BIT. LOW TEMPS WEDNESDAY NIGHT WILL DIP INTO THE 50S...WHILE HIGH TEMPS THURSDAY WILL BE IN THE 80S...UNDER CLEAR SKIES. LATE IN THE WEEK...WITH HIGH PRESSURE BUILDING IN OVER THE NORTH GULF...AND SOUTHEAST WINDS BECOMING MORE ESTABLISHED...CLOUD COVER WILL INCREASE BACK INTO THE PARTLY CLOUDY TO CLOUDY RANGE...WITH TEMPERATURES TRENDING TOWARD ABOVE NORMAL. MID LEVEL RIDGING WILL STILL DOMINATE JUST UPSTREAM...BUT A TROUGH WILL MOVE INTO THE LWR WEST COAST...AND THE AMPLIFIED PATTERN WILL FLATTEN. FRIDAY NIGHT INTO SATURDAY...INCREASING MOISTURE WILL SUPPORT A SLIGHT CHANCE OF SHOWERS AS MID LEVEL DIFFLUENCE FROM THE UPSTREAM TROUGH/LOW OVER THE SOUTHERN SOUTHWEST HELPS DESTABILIZE THINGS A BIT OVER DEEP SOUTH TEXAS AND THE RGV FRIDAY INTO SATURDAY. THE POTENTIAL FOR THE ARRIVAL OF A STRONGER FRONT WILL INCREASE SUNDAY NIGHT INTO MONDAY ACCORDING TO THE GFS AND ECMWF...AS THE EASTWARD MOVING TROUGH COINCIDES WITH A COLD FRONT MOVING SOUTH ACROSS THE REGION. THE GFS BRINGS A GOO AMOUNT OF RAIN THE THE CWA LATE SUNDAY NIGHT...WHILE THE ECMWF IS SLOWER AND KEEPS MOST OF THE RAIN NORTH OF THE CWA BUT BRINGS A SECONDARY FRONT THROUGH THE RGV MONDAY AFTERNOON TO EVENING. CHOSE TO GO WITH A BLEND...SINCE TIMING ISSUES WERE NOT EXTREME... AND WENT WITH A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY AND MONDAY NIGHT. THIS IS STILL AT THE TAIL END OF THE FORECAST... AND THERE IS A FAIR AMOUNT OF UNCERTAINTY WITH THE AMOUNT OF RAIN THAT MIGHT MATERIALIZE...BUT BOTH MODELS AGREE WITH A CANADIAN COLD FRONT COINCIDING WITH A SOUTHERN STREAM DISTURBANCE MOVING OVER AND AN AMPLIFIED MID LEVEL PATTERN WITH RIDGING OVER THE WEST AND A PHASING TROUGHING OVER THE NORTHERN PLAINS TO UPPER MIDWEST ON MONDAY. CONDITIONS WILL CLEAR OUT RAPIDLY POST FRONT WITH AN AMPLIFIED MID LEVEL RIDGE BUILDING IN QUICKLY AFTER THE FRONT. TEMPERATURES WILL DIP A HANDFUL OF DEGREES IN THE WAKE OF THE FRONT AS SKIES CLEAR. MARINE... NOW THROUGH WEDNESDAY...A SURGE OF NORTHWESTERLY WINDS IS EXPECTED TO ARRIVE LATER THIS MORNING AND EARLY THIS AFTERNOON. SMALL CRAFT SHOULD EXERCISE CAUTION ON THE LAGUNA MADRE AND NEARSHORE WATERS AND A SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR THE OFFSHORE WATERS FROM MID MORNING THROUGH THIS EVENING DUE TO STRONG NORTHWEST WINDS. SEAS WILL BE MODERATE NEARSHORE AND LIKELY AT LEAST BRIEFLY BECOME ROUGH OFFSHORE. BETTER CONDITIONS ARE EXPECTED LATE TUESDAY NIGHT INTO WEDNESDAY AS WIND SPEEDS DECREASE AND SHIFT TO THE EAST AND EVENTUALLY SOUTHEAST. SEAS ARE EXPECTED TO REMAIN MODERATE THROUGH WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...BROAD HIGH PRESSURE OVER THE NORTHWEST GULF WILL INITIALIZE THE LONG TERM FORECAST WITH LIGHT TO MODERATE SOUTHEAST WINDS AND LOW SEAS. THEREAFTER THOUGH...THROUGH SATURDAY...SOUTHEAST WINDS WILL PUSH 20 KNOTS AND SEAS WILL INCREASE TO 5 TO 7 FEET OFFSHORE AS LOWER PRESSURE OVER THE SOUTHERN PLAINS INTERACTS WITH GULF HIGH PRESSURE TO GENERATE SOMEWHAT STRONGER WINDS. RAIN CHANCES WILL BE LOW TO NEARLY NONEXISTENT. FIRE WEATHER... ELEVATED AND CRITICAL FIRE DANGER IS FORECAST ACROSS THE RIO GRANDE VALLEY AND DEEP SOUTH TEXAS TODAY. A SURGE OF NORTHWEST WINDS WILL USHER IN MUCH DRIER AIR LATE THIS MORNING AND THIS AFTERNOON. RELATIVE HUMIDITY VALUES WILL FALL TO AROUND 12 TO 18 PERCENT WITH 20 FOOT WIND SPEEDS AROUND 15 MPH. A RED FLAG WARNING HAS BEEN ISSUED FOR STARR...BROOKS...KENEDY...AND INLAND CAMERON AND WILLACY COUNTIES TODAY AND ENHANCED FIRE DANGER CONDITIONS WILL EXIST ACROSS THE REMAINDER OF THE AREA. WIND SPEEDS ARE EXPECTED TO BE LOWER ON WEDNESDAY WITH RELATIVE HUMIDITY VALUES INCREASING. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...RED FLAG WARNING UNTIL 6 PM CDT THIS EVENING FOR TXZ250>255. GM...SMALL CRAFT ADVISORY UNTIL 1 AM CDT WEDNESDAY FOR GMZ170-175. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 59/51