Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/03/13


AREA FORECAST DISCUSSION
NWS PUEBLO CO
1126 AM MDT MON APR 1 2013 .UPDATE... ISSUED AT 1121 AM MDT MON APR 1 2013 PLAN TO DECREASE POPS SIGNIFICANTLY BETWEEN NOW AND MIDDAY TOMORROW ACROSS MANY PARTS OF THE REGION. DRY SLOT WILL SIGNIFICANTLY DECREASE PRECIP CHANCES BETWEEN NOW AND THEN. BEST CHANCES OF POPS DURING THE NEXT 24H WILL BE OVER FAR E PLAINS AND C MTN REGIONS. STILL EXPECT LOW CLOUDS TO INVADE ALL OF THE PLAINS LATER THIS EVENING. UPDATE WILL BE ISSUED AROUND 1 PM. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM MDT MON APR 1 2013 A SHORTWAVE TROF IS WRAPPING AROUND AN UPR LOW THAT IS OVR THE WRN STATES...AND IS BRINGING CLOUDS AND SOME PCPN TO PORTIONS OF WRN CO...SOME OF WHICH WL AFFECT THE CONTDVD THIS MORNING. ALSO THIS MORNING A FRONT IS CONTINUING TO MOVE SOUTHWARD THROUGH THE SERN PLAINS AS OF 3AM IT HAD MOVED SOUTH OF THE ARKANSAS RIVER VALLEY. HAVE SEEN SOME STRATUS DEVELOP BEHIND THIS FRONT IN NE AND PORTIONS OF NWRN KS. THE HRRR AND NAM12 SHOW LOW LEVEL RH VALUES/STRATUS BACKING INTO THE FAR SERN PLAINS A LITTLE LATER THIS MORNING...AND MAYBE BACKING INTO THE FAR ERN PORTIONS OF EL PASO COUNTY. THE NAM AND THE HRRR KEEP THE FAR SERN PLAINS DRY THRU THE MORNING HOURS...WHILE THE GFS PRINTS OUT SOME LIGHT QPF ASSOCIATED WITH THE STRATUS. DO NOT FEEL THAT MEASURABLE PCPN WL OCCUR SO WL KEEP THE FORECAST DRY OUT EAST...AND WL ONLY HAVE POPS ALONG THE CONTDVD THIS MORNING. THIS AFTERNOON THE NAM AND GFS SHOW THE BEST PCPN CHANCES BEING OVR THE CENTRAL CO MTS AND OVR PIKES PEAK AND TELLER COUNTY. THE NSSL WRF SHOWS PCPN IN THESE AREAS AS WELL...BUT ALSO SHOWS A BAND OF PCPN MOVING FROM THE SW ACRS THE SWRN MTS...THE SAN LUIS VALLEY...THE SANGRE DE CRISTO MTS...AND THEN ONTO THE ADJACENT I-25 CORRIDOR BY EARLY EVENING...AND THEN MOVING ACRS THE SERN PLAINS THRU THE EVENING. WL LEAN CLOSER TO THE WRF`S SOLUTION. SHOULD SEE SOME LIGHT SNOW ACCUMS OVR THE HIGHEST ELEVATIONS. TEMPS TODAY WL BE COOLER THAN YESTERDAY OVR THE SERN PLAINS IN THE WAKE OF THE FRONT...BUT GUIDANCE TEMPS ARE NOT IN GOOD AGREEMENT SO WL SPLIT THE DIFFERENCE. COULD SEE SOME LOW CLOUDS HANGING AROUND OVR THE FAR SERN CORNER INTO THE AFTERNOON WHICH WOULD KEEP TEMPS EVEN COOLER OUT THERE. SOME WRN AREAS WL BE A LITTLE COOLER TODAY...WHILE THE SAN LUIS VALLEY WL LIKELY SEE TEMPS SIMILAR TO THOSE ON SUN. OVERNIGHT THE UPR LOW WL MOVE INTO ERN UT AND MUCH OF THE FORECAST AREA ENDS UP IN THE DRY SLOT...AS SHOW IN THE NAM12...THE NSSL WRF AND THE GFS. THE CENTRAL MTS WL PROBABLY CONTINUE TO HAVE SOME PCPN THRU THE NIGHT...BUT SHOULD GENERALLY BE LIGHT. WITH MOIST LOW LEVEL UPSLOPE OVR THE ERN PLAINS TONIGHT...WIDESPREAD STRATUS IS EXPECTED. THE ONLY AREA THAT ALL THE MODELS SHOW WIDESPREAD PCPN TONIGHT IS OVR THE FAR SERN PLAINS...SO WL GO WITH LIKELY POPS IN THAT AREA...WITH DECREASING POPS WESTWARD TO THE ERN MTS. THE NAM AND GFS SHOW A FEW HUNDREDTHS OF PCPN OVR THE FAR ERN AREAS OVERNIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 420 AM MDT MON APR 1 2013 TUESDAY AND WEDNESDAY...THE UPPER LOW PRES SYSTEM TRACKS FROM THE NW TO THE SE DIRECTLY ACROSS COLORADO ON TUE AND WED...BRINGING A DECENT SHOT AT SOME PCPN FOR THE FORECAST AREA. STARTING OUT TUE MORNING...THE UPPER SYSTEM SHOULD BE PRODUCING SOME SHOWERS FOR THE CENT MTS...WHILE LLVL EASTERLY UPSLOPE FLOW DUE TO SFC HI PRES OVER NE AND KS WILL KEEP A SOLID THREAT OF PCPN FOR THE EASTERN PLAINS. HOWEVER...AS THE UPPER LOW CONTINUES TO TRACK ACROSS THE STATE...PCPN CHANCES SPREAD TO MUCH OF THE AREA BY TUE AFTN AND REMAIN PROBABLE THROUGH THE NIGHT. ONGOING POP GRIDS LOOKED REASONABLE FOR TUE NIGHT AND EARLY WED MORN WITH ONLY SLIGHT ADJUSTMENTS NEEDED. THE TROUGH AXIS EXITS THE SE CORNER OF THE STATE WED MID-MORNING...WITH PCPN THEN TAPERING OFF QUICKLY. AS FOR TEMPS...MAX TEMPS IN THE 40S FOR TUE WILL GRADUALLY WARM INTO THE 50S FOR WED. WEDNESDAY NIGHT THROUGH THURSDAY NIGHT..THE REGION DRIES OUT AS AN UPPER RIDGE OF HIGH PRESSURE MOVES ACROSS THE 4 CORNERS. TEMPS SHOULD REMAIN COOL FOR WED...THEN REBOUND INTO THE MID TO UPPER 60S FOR THU. FRIDAY THROUGH SUNDAY...THE EXTENDED MODELS WANT TO KEEP THINGS A BIT UNSETTLED OVER THE WEEKEND. ONE DISTURBANCE ROLLS ACROSS THE ROCKIES ON FRIDAY BUT LOOKS LIKE IT WILL STAY MAINLY TO THE NORTH OF THE STATE. A BRIEF BREAK ON SAT...THEN SAT NIGHT ANOTHER SHORTWAVE TRACKS ACROSS THE GREAT BASIN AND DIGS FURTHER SOUTH...PROMISING A BETTER SHOT AT SOME BENEFICIAL PCPN. FOR THE TIME BEING...KEPT ISOLATED POPS OVER THE MTS OVER THE WEEKEND AS THE EXTENDED PROCEDURE PRODUCED...AND WILL HAVE TO FINE TUNE AS THAT WINDOW NEARS. FOR THE TIME BEING...FRIDAY LOOKS LIKE THE WARMEST DAY OF THE EXTENDED FORECAST PERIOD. MOORE && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1121 AM MDT MON APR 1 2013 I DO NOT EXPECT ANY SIGNIF PRECIP IN THE TAFS (KCOS...KPUB...KALS) NEXT 24H. MAIN CONCERN WILL BE LOW CIGS MOVING INTO KCOS AND KPUB AROUND MIDNIGHT TONIGHT AND LASTING THROUGH THE END OF THE TAF PD. MVFR CIGS ARE LIKELY AT KPUB AND KCOS AFTER MIDNIGHT TONIGHT. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HODANISH SHORT TERM...28 LONG TERM...MOORE AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1018 AM MDT MON APR 1 2013 .UPDATE...NO CHANGES TO THE FORECAST ANTICIPATED THIS TIME AROUND. UPPER LOW CENTER HAS MOVED INTO SOUTHWESTERN UTAH WITH DEFORMATION BAND CLOUDINESS OUT AHEAD OF IT SPREADING OVER WESTERN AND CENTRAL COLORADO. RECENT LIGHTNING DATA PLOTS HAVE SHOWN SOME STRIKES TO THE SOUTH OF VERNAL...UTAH AND ONE OR TWO FLASHES AROUND KGJT. THIS IS INDICATIVE OF THE INSTABILITY PRESENT IN THE DEFORMATION ZONE. THE CURRENT FORECASTS ALREADY MENTION SOME THUNDER OVER THE MOUNTAINS THIS AFTERNOON...WHICH WILL BE LEFT ALONE. KCCU IS ALSO INDICATING SOME SNOW ALREADY FALLING OVER THE HIGHER MOUNTAINS. ACROSS THE EASTERN COLORADO PLAINS...EASTERLY FLOW WILL PERSIST THROUGH THE DAY WHICH MAY HELP SHOWER ACTIVITY TO DEVELOP ALONG THE FOOTHILLS LATE IN THE AFTERNOON. EACH OF THESE FEATURES IS ADEQUATELY COVERED IN THE CURRENT FORECAST. && .AVIATION...HIGH CEILINGS WILL BE DEVELOPING BY EARLY AFTERNOON AND THEN BEGIN LOWERING BY EVENING. SCATTERED SHOWERS WILL BE POSSIBLE THROUGH THE EVENING...BUT MOST ACTIVITY SHOULD BE CLOSER TO THE FOOTHILLS. WINDS SHOULD REMAIN OUT OF THE EAST AND SOUTHEAST THROUGH THE AFTERNOON. A MIX OF RAIN AND SNOW SHOWERS ARE EXPECTED OVERNIGHT WITH A COMPLETE CHANGEOVER TO SNOW POSSIBLE BEFORE SUNRISE TUESDAY. TEMPERATURES SHOULD BE JUST COLD ENOUGH TO ALLOW SNOW TO FALL...BUT GROUND TEMPERATURES SHOULD BE WARM ENOUGH TO LIMIT ANY ACCUMULATION. && .PREV DISCUSSION... /ISSUED 340 AM MDT MON APR 1 2013/ SHORT TERM...AN UPPER LEVEL LOW WILL MOVE FROM NEVADA INTO UTAH BY THIS EVENING. AHEAD OF THE LOW THE FLOW ALOFT WILL BE SWLY. AT THE SURFACE HIGH PRES WILL BE OVER THE CNTRL PLAINS WITH LOW PRES OVER WRN COLORADO. THIS WILL LEAD TO SELY LOW LVL FLOW OVER NERN CO THRU TONIGHT. CROSS- SECTIONS SHOW AN INCREASE IN MOISTURE WITH SOME MID LVL QG ASCENT MAINLY LATE TONIGHT. LAPSE RATES ARE BEST OVER THE HIGHER TERRAIN WITH LESS INSTABILITY OVER THE PLAINS. AT THIS TIME THE BEST CHC OF PCPN THRU THIS AFTN LOOKS TO BE IN THE MTNS WITH DRY CONDITIONS OVER THE PLAINS. WILL MENTION SOME THUNDER IN THE MTNS WHERE SOME CAPE EXISTS. HIGHS THIS AFTN OVER NERN CO WILL RANGE FM THE UPPER 40S TO LOWER 50S EXCEPT POSSIBLY ALONG THE FRONT RANGE WHERE SELY LOW LVL WINDS COMING OFF THE PALMER DIVIDE COULD ALLOW FOR READINGS TO RISE INTO THE MID TO UPPER 50S NR DENVER. THE RAP SHOWS HIGHS IN THE LOWER TO MID 60S AROUND DENVER HOWEVER WILL NOT GO THIS WARM. FOR TONIGHT SNOW SHOWERS WILL CONTINUE IN THE MTNS DUE TO INCREASING QG ASCENT HOWEVER SWLY OROGRAPHIC FLOW MAY KEEP ACCUMULATIONS ON THE LIGHT SIDE IN MOST AREAS. EAST OF THE MTNS THE LOW LVL FLOW WILL REMAIN SELY. SHOULD SEE SOME SHOWERS DVLP IN THE FOOTHILLS BY EARLY EVENING WITH SOME OF THE ACTIVITY SPREADING ACROSS THE ADJACENT PLAINS OVERNIGHT. WITH SELY LOW LVL FLOW THE BEST CHC OF PCPN MAY FOCUS IN THE NRN FOOTHILLS AND NORTH OF A DENVER TO LIMON LINE. AT THIS TIME OVERALL CONFIDENCE IS NOT VERY HIGH AS TO WHERE TO MENTION LIKELY POPS OVER THE PLAINS TONIGHT SO WILL KEEP POPS IN THE CHC CATEGORY. SOUNDINGS SHOW WET BULB ZEROS WILL BECOME LOW ENOUGH FOR SHOWERS TO MIX WITH OR CHANGE TO SOME SNOW AFTER MIDNIGHT ACROSS THE PLAINS HOWEVER AT THIS TIME IT LOOKS LIKE ANY ACCUMULATION WILL BE AN INCH OR LESS. LONG TERM...MODELS HAVE THE UPPER CLOSED LOW OVER EAST CENTRAL UTAH...THEN OVER THE FOUR CORNERS AT 00Z TUESDAY AFTERNOON. BY 18Z WEDNESDAY...ITS OVER SOUTHEASTERN/ WESTERN KANSAS. ON WEDNESDAY NIGHT...INCREASING NORTHWESTERLY FLOW ALOFT IS PROGGED FOR THE FORECAST AREA. THE QG VERTICAL VELOCITY FIELDS HAVE UPWARD MOTION OVER THE CWA TUESDAY AND TUESDAY NIGHT ...HOWEVER IT IS NOT VERY STRONG. WEAK DOWNWARD MOTION IS PROGGED WEDNESDAY AND WEDNESDAY NIGHT. NORTHEAST TO SOUTHEASTERLY LOW LEVEL WINDS ARE PROGGED FOR THE PLAINS AND FOOTHILLS TUESDAY AND TUESDAY EVENING. WEAK FLOW IS PROGGED THE REST OF TUESDAY NIGHT THROUGH WEDNESDAY...WITH A COMBINATION OF NORMAL DUIRNAL PATTERNS TO WEAK DOWNSLOPING WEDNESDAY NIGHT. MOISTURE IS FAIRLY DEEP ON TUESDAY FOR MOST OF THE CWA. IT IS PRETTY DEEP ON THE NAM TUESDAY NIGHT...DRIER ON THE GFS. IT DRIES OUT SOMEWHAT ON WEDNESDAY. THERE IS SOME MOUNTAIN MOISTURE WEDNESDAY NIGHT...BUT ITS DRIER ON THE PLAINS. MODELS SHOW MINOR CAPE OVER THE MOUNTAINS AND FOOTHILLS LATE DAY TUESDAY AND AGAIN WEDNESDAY AFTERNOON. THE QPF FIELDS SHOW MEASURABLE PRECIPITATION TUESDAY AND TUESDAY EVENING FOR MOST AREAS...BEST OVER THE FOOTHILLS AND EASTERN MOUNTIANS ZONES. THERE IS A TAD THE REST OF TUESDAY NIGHT AND WEDNESDAY... MAINLY OVER THE MOUNTIANS. FOR POPS...WILL KEEP THE "LIKELY"S IN OVER THE MOUNTAINS AND "CHANCES" OUT ON THE PLAINS TUESDAY AND TUESDAY EVENING. THE PLAINS WILL SEE BOTH SNOW AND RAIN...WITH LITTLE ACCUMULATION. WILL DECREASE POPS THE REST OF TUESDAY NIGHT. ON WEDNESDAY...JUST SOME MINOR ALPINE POPS. WILL PUT "ISOLATED" THUNDER IN BOTH TUESDAY AND WEDNESDAY AFTERNOONS IN THE MOUNTIANS. FOR TEMPERATURES...TUESDAY`S HIGHS ARE 2.0-3.5 C COOLER THAN TODAY`S EXPECTED HIGHS. WEDNESDAY`S READINGS COME UP 3-7 C FROM TUESDAY`S. FOR THE LATER DAYS...THURSDAY THROUGH SUNDAY...MODELS HAVE UPPER RIDGING FOR COLORADO THROUGH MID DAY FRIDAY...THEN A WEAK UPPER TROUGH IS PROGGED ACROSS THE STATE BY EARLY SATURDAY MORNING. AFTER THAT...WEST-SOUTHWESTERLY FLOW ALOFT IS PROGGED OVER THE CWA THROUGH SUNDAY. THERE IS LIMITED MOISTURE AROUND...BUT IT INCREASES ON SUNDAY. AVIATION...SO FAR ANY STRATUS WAS CONFINED TO THE FAR NERN CORNER OF THE PLAINS SO AT THIS POINT IT DOES NOT APPEAR IT WILL AFFECT THE AIRPORT THIS MORNING. AS FOR WINDS BOTH THE RAP AND HRR SHOW A DENVER CYCLONE DEVELOPING SW OF DENVER WITH WINDS BEING E TO SE THRU THE AFTN. COULD SEE SUSTAINED WINDS IN THE 15 TO 20 MPH BY 20Z. AT THIS TIME ANY CHC FOR RAIN SHOWERS WILL BE AFTER 00Z. COULD SEE SHOWERS CHANGE TO SOME SNOW AFTER MIDNIGHT BUT ANY ACCUMULATION WILL BE UNDER ONE HALF INCH AND CONFINED TO GRASSY AREAS. LATEST NAM CONTINUES TO SHOW A CYCLONE OVERNIGHT OVER DENVER WITH WINDS BECOMING MORE SLY AFTER MIDNIGHT. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DANKERS LONG TERM....99 AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS PUEBLO CO
421 AM MDT MON APR 1 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 420 AM MDT MON APR 1 2013 A SHORTWAVE TROF IS WRAPPING AROUND AN UPR LOW THAT IS OVR THE WRN STATES...AND IS BRINGING CLOUDS AND SOME PCPN TO PORTIONS OF WRN CO...SOME OF WHICH WL AFFECT THE CONTDVD THIS MORNING. ALSO THIS MORNING A FRONT IS CONTINUING TO MOVE SOUTHWARD THROUGH THE SERN PLAINS AS OF 3AM IT HAD MOVED SOUTH OF THE ARKANSAS RIVER VALLEY. HAVE SEEN SOME STRATUS DEVELOP BEHIND THIS FRONT IN NE AND PORTIONS OF NWRN KS. THE HRRR AND NAM12 SHOW LOW LEVEL RH VALUES/STRATUS BACKING INTO THE FAR SERN PLAINS A LITTLE LATER THIS MORNING...AND MAYBE BACKING INTO THE FAR ERN PORTIONS OF EL PASO COUNTY. THE NAM AND THE HRRR KEEP THE FAR SERN PLAINS DRY THRU THE MORNING HOURS...WHILE THE GFS PRINTS OUT SOME LIGHT QPF ASSOCIATED WITH THE STRATUS. DO NOT FEEL THAT MEASURABLE PCPN WL OCCUR SO WL KEEP THE FORECAST DRY OUT EAST...AND WL ONLY HAVE POPS ALONG THE CONTDVD THIS MORNING. THIS AFTERNOON THE NAM AND GFS SHOW THE BEST PCPN CHANCES BEING OVR THE CENTRAL CO MTS AND OVR PIKES PEAK AND TELLER COUNTY. THE NSSL WRF SHOWS PCPN IN THESE AREAS AS WELL...BUT ALSO SHOWS A BAND OF PCPN MOVING FROM THE SW ACRS THE SWRN MTS...THE SAN LUIS VALLEY...THE SANGRE DE CRISTO MTS...AND THEN ONTO THE ADJACENT I-25 CORRIDOR BY EARLY EVENING...AND THEN MOVING ACRS THE SERN PLAINS THRU THE EVENING. WL LEAN CLOSER TO THE WRF`S SOLUTION. SHOULD SEE SOME LIGHT SNOW ACCUMS OVR THE HIGHEST ELEVATIONS. TEMPS TODAY WL BE COOLER THAN YESTERDAY OVR THE SERN PLAINS IN THE WAKE OF THE FRONT...BUT GUIDANCE TEMPS ARE NOT IN GOOD AGREEMENT SO WL SPLIT THE DIFFERENCE. COULD SEE SOME LOW CLOUDS HANGING AROUND OVR THE FAR SERN CORNER INTO THE AFTERNOON WHICH WOULD KEEP TEMPS EVEN COOLER OUT THERE. SOME WRN AREAS WL BE A LITTLE COOLER TODAY...WHILE THE SAN LUIS VALLEY WL LIKELY SEE TEMPS SIMILAR TO THOSE ON SUN. OVERNIGHT THE UPR LOW WL MOVE INTO ERN UT AND MUCH OF THE FORECAST AREA ENDS UP IN THE DRY SLOT...AS SHOW IN THE NAM12...THE NSSL WRF AND THE GFS. THE CENTRAL MTS WL PROBABLY CONTINUE TO HAVE SOME PCPN THRU THE NIGHT...BUT SHOULD GENERALLY BE LIGHT. WITH MOIST LOW LEVEL UPSLOPE OVR THE ERN PLAINS TONIGHT...WIDESPREAD STRATUS IS EXPECTED. THE ONLY AREA THAT ALL THE MODELS SHOW WIDESPREAD PCPN TONIGHT IS OVR THE FAR SERN PLAINS...SO WL GO WITH LIKELY POPS IN THAT AREA...WITH DECREASING POPS WESTWARD TO THE ERN MTS. THE NAM AND GFS SHOW A FEW HUNDREDTHS OF PCPN OVR THE FAR ERN AREAS OVERNIGHT. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 420 AM MDT MON APR 1 2013 TUESDAY AND WEDNESDAY...THE UPPER LOW PRES SYSTEM TRACKS FROM THE NW TO THE SE DIRECTLY ACROSS COLORADO ON TUE AND WED...BRINGING A DECENT SHOT AT SOME PCPN FOR THE FORECAST AREA. STARTING OUT TUE MORNING...THE UPPER SYSTEM SHOULD BE PRODUCING SOME SHOWERS FOR THE CENT MTS...WHILE LLVL EASTERLY UPSLOPE FLOW DUE TO SFC HI PRES OVER NE AND KS WILL KEEP A SOLID THREAT OF PCPN FOR THE EASTERN PLAINS. HOWEVER...AS THE UPPER LOW CONTINUES TO TRACK ACROSS THE STATE...PCPN CHANCES SPREAD TO MUCH OF THE AREA BY TUE AFTN AND REMAIN PROBABLE THROUGH THE NIGHT. ONGOING POP GRIDS LOOKED REASONABLE FOR TUE NIGHT AND EARLY WED MORN WITH ONLY SLIGHT ADJUSTMENTS NEEDED. THE TROUGH AXIS EXITS THE SE CORNER OF THE STATE WED MID-MORNING...WITH PCPN THEN TAPERING OFF QUICKLY. AS FOR TEMPS...MAX TEMPS IN THE 40S FOR TUE WILL GRADUALLY WARM INTO THE 50S FOR WED. WEDNESDAY NIGHT THROUGH THURSDAY NIGHT..THE REGION DRIES OUT AS AN UPPER RIDGE OF HIGH PRESSURE MOVES ACROSS THE 4 CORNERS. TEMPS SHOULD REMAIN COOL FOR WED...THEN REBOUND INTO THE MID TO UPPER 60S FOR THU. FRIDAY THROUGH SUNDAY...THE EXTENDED MODELS WANT TO KEEP THINGS A BIT UNSETTLED OVER THE WEEKEND. ONE DISTURBANCE ROLLS ACROSS THE ROCKIES ON FRIDAY BUT LOOKS LIKE IT WILL STAY MAINLY TO THE NORTH OF THE STATE. A BRIEF BREAK ON SAT...THEN SAT NIGHT ANOTHER SHORTWAVE TRACKS ACROSS THE GREAT BASIN AND DIGS FURTHER SOUTH...PROMISING A BETTER SHOT AT SOME BENEFICIAL PCPN. FOR THE TIME BEING...KEPT ISOLATED POPS OVER THE MTS OVER THE WEEKEND AS THE EXTENDED PROCEDURE PRODUCED...AND WILL HAVE TO FINE TUNE AS THAT WINDOW NEARS. FOR THE TIME BEING...FRIDAY LOOKS LIKE THE WARMEST DAY OF THE EXTENDED FORECAST PERIOD. MOORE && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 420 AM MDT MON APR 1 2013 EXPECT VFR CONDITIONS TODAY AT KALS...KPUB AND KCOS. THERE COULD BE A FEW LOW CLOUDS IN THE VCNTY OF KCOS THIS MORNING. EARLY THIS EVENING THERE COULD BE A FEW SHOWERS AND MAYBE EVEN A THUNDERSTORMS AT OR IN THE VCNTY OF KCOS...PROBABLY AFTER 22Z AND BEFORE 03Z. KALS COULD ALSO SEE SOME SHOWERS OR A THUNDERSTORM IN THE AREA...MAINLY AFTER 18Z AND BEFORE 01Z. KALS SHOULD HAVE VFR CONDITIONS TONIGHT. KCOS AND KPUB SHOULD SEE LOW CLOUDS MOVE INTO THE AREA AROUND 06Z WITH IFR CONDITIONS EXPECTED. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...MOORE AVIATION...28
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
340 AM MDT MON APR 1 2013 .SHORT TERM...AN UPPER LEVEL LOW WILL MOVE FROM NEVADA INTO UTAH BY THIS EVENING. AHEAD OF THE LOW THE FLOW ALOFT WILL BE SWLY. AT THE SURFACE HIGH PRES WILL BE OVER THE CNTRL PLAINS WITH LOW PRES OVER WRN COLORADO. THIS WILL LEAD TO SELY LOW LVL FLOW OVER NERN CO THRU TONIGHT. CROSS- SECTIONS SHOW AN INCREASE IN MOISTURE WITH SOME MID LVL QG ASCENT MAINLY LATE TONIGHT. LAPSE RATES ARE BEST OVER THE HIGHER TERRAIN WITH LESS INSTABILITY OVER THE PLAINS. AT THIS TIME THE BEST CHC OF PCPN THRU THIS AFTN LOOKS TO BE IN THE MTNS WITH DRY CONDITIONS OVER THE PLAINS. WILL MENTION SOME THUNDER IN THE MTNS WHERE SOME CAPE EXISTS. HIGHS THIS AFTN OVER NERN CO WILL RANGE FM THE UPPER 40S TO LOWER 50S EXCEPT POSSIBLY ALONG THE FRONT RANGE WHERE SELY LOW LVL WINDS COMING OFF THE PALMER DIVIDE COULD ALLOW FOR READINGS TO RISE INTO THE MID TO UPPER 50S NR DENVER. THE RAP SHOWS HIGHS IN THE LOWER TO MID 60S AROUND DENVER HOWEVER WILL NOT GO THIS WARM. FOR TONIGHT SNOW SHOWERS WILL CONTINUE IN THE MTNS DUE TO INCREASING QG ASCENT HOWEVER SWLY OROGRAPHIC FLOW MAY KEEP ACCUMULATIONS ON THE LIGHT SIDE IN MOST AREAS. EAST OF THE MTNS THE LOW LVL FLOW WILL REMAIN SELY. SHOULD SEE SOME SHOWERS DVLP IN THE FOOTHILLS BY EARLY EVENING WITH SOME OF THE ACTIVITY SPREADING ACROSS THE ADJACENT PLAINS OVERNIGHT. WITH SELY LOW LVL FLOW THE BEST CHC OF PCPN MAY FOCUS IN THE NRN FOOTHILLS AND NORTH OF A DENVER TO LIMON LINE. AT THIS TIME OVERALL CONFIDENCE IS NOT VERY HIGH AS TO WHERE TO MENTION LIKELY POPS OVER THE PLAINS TONIGHT SO WILL KEEP POPS IN THE CHC CATEGORY. SOUNDINGS SHOW WET BULB ZEROS WILL BECOME LOW ENOUGH FOR SHOWERS TO MIX WITH OR CHANGE TO SOME SNOW AFTER MIDNIGHT ACROSS THE PLAINS HOWEVER AT THIS TIME IT LOOKS LIKE ANY ACCUMULATION WILL BE AN INCH OR LESS. .LONG TERM...MODELS HAVE THE UPPER CLOSED LOW OVER EAST CENTRAL UTAH...THEN OVER THE FOUR CORNERS AT 00Z TUESDAY AFTERNOON. BY 18Z WEDNESDAY...ITS OVER SOUTHEASTERN/ WESTERN KANSAS. ON WEDNESDAY NIGHT...INCREASING NORTHWESTERLY FLOW ALOFT IS PROGGED FOR THE FORECAST AREA. THE QG VERTICAL VELOCITY FIELDS HAVE UPWARD MOTION OVER THE CWA TUESDAY AND TUESDAY NIGHT ...HOWEVER IT IS NOT VERY STRONG. WEAK DOWNWARD MOTION IS PROGGED WEDNESDAY AND WEDNESDAY NIGHT. NORTHEAST TO SOUTHEASTERLY LOW LEVEL WINDS ARE PROGGED FOR THE PLAINS AND FOOTHILLS TUESDAY AND TUESDAY EVENING. WEAK FLOW IS PROGGED THE REST OF TUESDAY NIGHT THROUGH WEDNESDAY...WITH A COMBINATION OF NORMAL DUIRNAL PATTERNS TO WEAK DOWNSLOPING WEDNESDAY NIGHT. MOISTURE IS FAIRLY DEEP ON TUESDAY FOR MOST OF THE CWA. IT IS PRETTY DEEP ON THE NAM TUESDAY NIGHT...DRIER ON THE GFS. IT DRIES OUT SOMEWHAT ON WEDNESDAY. THERE IS SOME MOUNTAIN MOISTURE WEDNESDAY NIGHT...BUT ITS DRIER ON THE PLAINS. MODELS SHOW MINOR CAPE OVER THE MOUNTAINS AND FOOTHILLS LATE DAY TUESDAY AND AGAIN WEDNESDAY AFTERNOON. THE QPF FIELDS SHOW MEASURABLE PRECIPITATION TUESDAY AND TUESDAY EVENING FOR MOST AREAS...BEST OVER THE FOOTHILLS AND EASTERN MOUNTIANS ZONES. THERE IS A TAD THE REST OF TUESDAY NIGHT AND WEDNESDAY... MAINLY OVER THE MOUNTIANS. FOR POPS...WILL KEEP THE "LIKELY"S IN OVER THE MOUNTAINS AND "CHANCES" OUT ON THE PLAINS TUESDAY AND TUESDAY EVENING. THE PLAINS WILL SEE BOTH SNOW AND RAIN...WITH LITTLE ACCUMULATION. WILL DECREASE POPS THE REST OF TUESDAY NIGHT. ON WEDNESDAY...JUST SOME MINOR ALPINE POPS. WILL PUT "ISOLATED" THUNDER IN BOTH TUESDAY AND WEDNESDAY AFTERNOONS IN THE MOUNTIANS. FOR TEMPERATURES...TUESDAY`S HIGHS ARE 2.0-3.5 C COOLER THAN TODAY`S EXPECTED HIGHS. WEDNESDAY`S READINGS COME UP 3-7 C FROM TUESDAY`S. FOR THE LATER DAYS...THURSDAY THROUGH SUNDAY...MODELS HAVE UPPER RIDGING FOR COLORADO THROUGH MID DAY FRIDAY...THEN A WEAK UPPER TROUGH IS PROGGED ACROSS THE STATE BY EARLY SATURDAY MORNING. AFTER THAT...WEST-SOUTHWESTERLY FLOW ALOFT IS PROGGED OVER THE CWA THROUGH SUNDAY. THERE IS LIMITED MOISTURE AROUND...BUT IT INCREASES ON SUNDAY. && .AVIATION...SO FAR ANY STRATUS WAS CONFINED TO THE FAR NERN CORNER OF THE PLAINS SO AT THIS POINT IT DOES NOT APPEAR IT WILL AFFECT THE AIRPORT THIS MORNING. AS FOR WINDS BOTH THE RAP AND HRR SHOW A DENVER CYCLONE DEVELOPING SW OF DENVER WITH WINDS BEING E TO SE THRU THE AFTN. COULD SEE SUSTAINED WINDS IN THE 15 TO 20 MPH BY 20Z. AT THIS TIME ANY CHC FOR RAIN SHOWERS WILL BE AFTER 00Z. COULD SEE SHOWERS CHANGE TO SOME SNOW AFTER MIDNIGHT BUT ANY ACCUMULATION WILL BE UNDER ONE HALF INCH AND CONFINED TO GRASSY AREAS. LATEST NAM CONTINUES TO SHOW A CYCLONE OVERNIGHT OVER DENVER WITH WINDS BECOMING MORE SLY AFTER MIDNIGHT. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RPK LONG TERM....RJK AVIATION...RPK
AREA FORECAST DISCUSSION
NWS MIAMI FL
150 PM EDT MON APR 1 2013 .AVIATION... SHOWERS AND THUNDERSTORMS ARE EXPECTED TO CONTINUE DEVELOPING ACROSS THE EASTERN PORTION OF THE PENINSULA THIS AFTERNOON. FOR THE VERY SHORT TERM...SHOWERS AND THUNDERSTORMS ARE IN THE VICINITY OF TERMINALS KTMB...KMIA AND KOPF WITH BRIEF PERIODS OF IFR CONDITIONS POSSIBLE. THERE IS A SLIGHT RISK OF SEVERE WEATHER WITH ANY THUNDERSTORMS THAT DEVELOP THIS AFTERNOON AND EARLY EVENING. AFTER THE EARLY EVENING HOURS THE POTENTIAL FOR CONVECTION WILL START TO DECREASE. FOR THE EAST COAST TERMINALS...AS SOUTHWESTERLY WINDS CONTINUE TO DEVELOP THE CHANCES OF A SEA BREEZE THIS AFTERNOON ARE DIMINISHING BUT WINDS COULD BE SOMEWHAT VARIABLE AT TIMES. 60 && .PREV DISCUSSION... /ISSUED 1031 AM EDT MON APR 1 2013/ UPDATE... THE MORNING SURFACE ANALYSIS SHOWED A HIGH PRESSURE RIDGE AXIS EXTENDING WEST ACROSS SOUTH FLORIDA AND THE SOUTHEAST GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE NORTH. SSW LOW-LEVEL FLOW IS EXPECTED TO GRADUALLY VEER TOWARD THE WEST THROUGH THE COURSE OF THE DAY AS THIS BOUNDARY CONTINUES SOUTH. THIS FLOW COMBINED WITH THE AFTERNOON EAST COAST SEA BREEZE...A COUPLE OF IMPULSES ALOFT AND MODERATE INSTABILITY AND SHEAR (0-6KM 30-35 KT) COULD GENERATE A FEW STRONG TO EVEN SEVERE THUNDERSTORMS THROUGH THE AFTERNOON/EVENING PERIOD TODAY OVER THE METRO/EAST COAST LOCATIONS. THE LATEST WRF AND HRRR MODEL REFLECTIVITIES... HOWEVER...ARE ONLY INDICATING ISOLATED COVERAGE OVER THESE AREAS AT BEST THROUGH THIS TIME. ANY STORMS THAT DO INITIATE COULD BE CAPABLE OF PRODUCING STRONG WINDS, HAIL AND POSSIBLY A TORNADO. THE LATEST FORECAST HAS BEEN UPDATED TO REFLECT THIS POTENTIAL THIS AFTERNOON. ELSEWHERE...VISIBILITIES HAVE BEGUN TO IMPROVE OVER THE PAST HOUR ACROSS THE INTERIOR LOCATIONS FROM THE EARLY MORNING FOG AND THIS TREND IS EXPECTED TO CONTINUE. THE LOCAL OFFICIALS HAVE REPORTED THAT SEGMENTS OF I-75 HAVE BEEN CLOSED TODAY DUE TO A COMBINATION OF THIS FOG EARLIER AND SMOKE FROM THE ONGOING WILDFIRE IN COLLIER COUNTY. PREV DISCUSSION... /ISSUED 739 AM EDT MON APR 1 2013/ AVIATION... AN UPPER LEVEL SHORTWAVE ACROSS THE EASTERN GULF WILL MOVE ACROSS THE FLORIDA PENINSULA TODAY. A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MAINLY TO THE EAST OF THE EAST COAST TAF SITES THIS MORNING. SEA BREEZE BOUNDARIES EARLY THIS AFTERNOON ARE EXPECTED TO HELP GENERATE SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS NEAR THE EAST COAST TAF SITES. SO ADDED VCTS FOR THE EAST COAST TAFS. FOR KAPF...THERE IS A SLIGHT CHANCE OF SHOWERS AHEAD OF THE TROUGH...MAINLY BEFORE 18Z. WIND DIRECTION MAY VARY BETWEEN 160-210 DEGREES DURING THE DAY AT THE EAST COAST TAF SITES. WINDS WILL SHIFT TO THE WEST TO NORTHWEST TONIGHT BEHIND THE BOUNDARY. PREV DISCUSSION... /ISSUED 459 AM EDT MON APR 1 2013/ DISCUSSION... CURRENTLY, A MID LEVEL TROUGH, ROUGHLY AT 700 MB, IS MOVING ACROSS THE EASTERN GULF OF MEXICO. THIS HAS GENERATED A LINE OF THUNDERSTORMS THAT IS EXPECTED TO FALL APART AS IT APPROACHES CENTRAL FLORIDA. THIS TROUGH, ACCORDING TO THE HRRR, MAY SPARK OFF A FEW SHOWERS OVER SOUTH FLORIDA THIS MORNING. ALSO, ANOTHER SHORT WAVE HAS GENERATED SOME SHOWERS AND ISOLATED THUNDERSTORMS OVER THE FLORIDA STRAITS. THESE ARE MOVING NORTH NORTHEAST. THE SHOWERS WILL AFFECT THE SOUTHEASTERN PORTION OF THE CWA THIS MORNING. THE QUESTION IS IF THERE WILL BE ANY THUNDERSTORMS THAT MOVE INTO THE AREA AS WELL. THERE IS AROUND 1000 JOULES JUST ONSHORE, AROUND HOMESTEAD AND MIAMI. SO, ALTHOUGH ORIGINAL THINKING WAS THEY WOULD STAY OFFSHORE, MAY HAVE TO ADD A MENTION OF THUNDERSTORMS FOR THIS AREA THIS MORNING. AS FOR LATER TODAY, MODELS INDICATE THE TROUGH, OR REALLY, A WEAKENING FRONT, WILL MOVE ONSHORE THE GULF COAST LATER THIS MORNING. MODELS ARE INDICATING IT WILL NOT BE TOO ACTIVE, CONVECTION WISE WHEN IT DOES. BUT, AS IT PROGRESS ACROSS THE STATE, ALONG WITH DAYTIME HEATING, CONVECTION MAY BE ABLE TO INITIATE. THE MODELS DO DIFFER GREATLY WITH HOW MUCH CAPE WILL BE AVAILABLE. THE GFS KEEPS THE HIGHEST BOUNDARY LAYER CAPE VALUES WELL OFFSHORE AND ONLY 500-600 JOULES OVER THE ATLANTIC COAST. THE NAM, ON THE OTHER HAND, HAS 1200 TO 1600 JOULES OVER THE ATLANTIC COAST, NEAT WEST PALM BEACH, AND DROPS TO 500-700 JOULES NEAR MIAMI. NOW THE NAM MODEL SOUNDINGS HAVE 1200-1600 JOULES ALL OVER THE ATLANTIC COAST. THEY DO SHOW A WEAK CAP FURTHER NORTH, BUT IT IS SO WEAK, NOT THINKING IT WILL BE A REAL INHIBITOR. THERE IS ALSO A TOUCH OF CIN TO THE NORTH AS WELL, BUT AGAIN, NOTHING THAT REALLY SHOULD INHIBIT DEVELOPMENT. SO, WHAT WILL INHIBIT THEIR DEVELOPMENT. WELL, MODELS DO SHOW THAT THE CAPE WILL BE PUSHING OFF TO THE EAST, AHEAD OF THE TROUGH. SO, WE MAY BE LACKING THE LIFTING MECHANISM. IT MAY ARRIVE WELL AFTER THE CAPE HAS PUSHED OFF SHORE. SO, HAVE KEPT CHC POPS AND SLIGHT CHC TSTMS, BUT HAVE BROADENED THE COVERAGE OF TSTMS THIS AFTERNOON. BEHIND THE TROUGH TODAY, HIGH PRESSURE WILL BE BUILDING IN FAIRLY QUICK. THIS WILL BRING QUIET WEATHER BACK TO SOUTH FLORIDA FOR A FEW DAYS. FOR FRIDAY AND THE WEEKEND, A LOW PRESSURE SYSTEM WILL DEVELOP OVER THE WESTERN GULF AND MOVE OVER THE FLORIDA PANHANDLE THURSDAY NIGHT/FRIDAY MORNING. A COLD FRONT WILL MOVE THROUGH SOUTH FLORIDA FRIDAY. THIS SYSTEM WILL BRING OUR NEXT CHANCE FOR RAIN AND POSSIBLY A THUNDERSTORM. MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE STRENGTH, POSITION, AND TIMING OF THIS SYSTEM. GIVEN THIS, HAVE A HIGH CHC POP IN THE FORECAST FOR FRIDAY. BEHIND THE FRONT, HIGH PRESSURE WILL BUILD IN ONCE AGAIN. TEMPERATURES WILL NOT BE MUCH COOLER, ONLY A FEW DEGREES. THIS HIGH PRESSURE WILL LAST FOR THE REMAINDER OF THE EXTENDED FORECAST. MARINE... WINDS AHEAD OF A WEAK FRONT/TROUGH WILL PICK UP OUT OF THE SOUTH TO BETWEEN 13 AND 19 KTS OVER THE ATLANTIC WATERS. THEY SHOULD REMAIN BELOW 10 KTS OVER THE GULF WATERS. THE HIGHER WIND SPEEDS OVER THE ATLANTIC WATERS HAS PROMPTED A SMALL CRAFT SHOULD EXERCISE CAUTION STATEMENT FOR THIS AFTERNOON. SEAS TODAY WILL BE SUBSIDING SOMEWHAT, EVEN WITH THE WINDS, AND ARE EXPECTED TO BE 1 TO 3 FEET BY TOMORROW IN THE ATLANTIC WATERS. THE GULF WATERS WILL BE AROUND 1 FOOT FOR THE NEXT COUPLE OF DAYS. HIGH PRESSURE WILL BUILD IN BEGINNING TONIGHT. THIS WILL CAUSE WINDS TO WEAKEN SOME TONIGHT TO 7-10 KTS OVER THE ATLANTIC AND SHIFT THEM OUT OF THE NORTH TOMORROW. FIRE WEATHER... THE MAIN FIRE WEATHER CONCERN TODAY ARE THE SHIFTING WINDS. AN APPROACHING FRONT/TROUGH WILL CAUSE WINDS TO PICK UP SOME TODAY TO 10 TO 15 MPH OVER GLADES, HENDRY, AND INTERIOR COLLIER COUNTIES. THEY WILL BEGIN OUT OF THE SOUTHEAST, BUT TURN THROUGH THE DAY TO THE SOUTH, THEN SOUTHWEST BY EARLY AFTERNOON. BY THIS EVENING, THEY WILL BECOME WESTERLY BETWEEN 5 AND 10 MPH. ALONG WITH THIS WIND SHIFT, WILL BE THE CHANCE FOR SOME RAIN SHOWERS AND A SLIGHT CHANCE FOR A THUNDERSTORM. THE CHANCES INCREASE AS YOU GO EASTWARD ACROSS SOUTH FLORIDA. IN THE INTERIOR PORTION OF THE AREA, THE DIVIDING LINE FOR THE CHANCE OF AND THUNDERSTORMS IS A DIFFICULT ONE AT BEST. SO, AREAS WEST OF THE FORECASTED AREA, SHOULD REMAIN AWARE OF THE POSSIBILITY THAT THE FORECAST COULD CHANGE TO INCLUDE THEM AS THE TROUGH GETS CLOSER. ONE THE OTHER HAND, IT COULD ALSO BE PUSHED FURTHER EAST. THERE IS JUST GREAT UNCERTAINTY WITH THE CONVECTIVE DEVELOPMENT TODAY. BEHIND THE TROUGH, HIGH PRESSURE WILL BUILD IN THROUGH THURSDAY, BRINGING QUIET WEATHER BACK TO SOUTH FLORIDA. PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 1 2013/ AVIATION... ISOLATED SHOWERS WERE MOVING ACROSS THE ATLANTIC WATERS AND NEAR KFLL AND FXE. ANOTHER AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS WERE MOVING JUST SOUTH OF THE KEYS. THIS AREA OF SHOWERS AND STORMS WILL CONTINUE TO MOVE NORTHWARD OVERNIGHT...AND COULD GET NEAR KTMB AND KMIA IN THE NEXT FEW HOURS IF THEY HOLD TOGETHER. A SHORTWAVE TROUGH MOVING ACROSS THE EASTERN GULF WAS FORCING SHOWERS AND THUNDERSTORMS TO DEVELOP WEST OF TAMPA. THE HRRR KEEPS THIS LINE TOGETHER AND MOVES IT TOWARDS KAPF AROUND 16Z. OTHER SHOWERS OR STORMS COULD ALSO BEGIN DEVELOPING ON THE EAST COAST SEA BREEZE AROUND THIS TIME. THE WIND DIRECTION IS ALSO TRICKY TODAY AS THE BOUNDARY LAYER WINDS SHIFT TO THE SOUTHWEST AHEAD OF THE TROUGH AND WEAK COLD FRONT. SO THE WINDS MAY SHIFT TO THE SOUTHWEST FOR A TIME LATE IN THE MORNING BEFORE THE EAST COAST SEA BREEZE BOUNDARY TRIES TO PUSH THE WINDS BACK TO THE SOUTH OR SOUTHEAST. BY 00Z...SOUTHWESTERLY FLOW IS EXPECTED TO PREVAIL...WITH WEST TO NORTHWESTERLY FLOW BEHIND THE SURFACE TROUGH AFTER 02-04Z. SO FOR THE TAFS...KEPT VCSH FOR NOW...BUT MAY NEED TO ADD VCTS. MVFR CONDITIONS ARE POSSIBLE NEAR ANY SHOWERS OR STORMS THAT FORM. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 65 81 67 81 / 20 10 - 10 FORT LAUDERDALE 68 84 71 83 / 20 10 - 10 MIAMI 68 85 69 82 / 20 10 - 10 NAPLES 65 83 64 85 / 10 10 - 10 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...85/AG AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS MIAMI FL
1031 AM EDT MON APR 1 2013 .UPDATE... THE MORNING SURFACE ANALYSIS SHOWED A HIGH PRESSURE RIDGE AXIS EXTENDING WEST ACROSS SOUTH FLORIDA AND THE SOUTHEAST GULF OF MEXICO AND A COLD FRONT APPROACHING FROM THE NORTH. SSW LOW-LEVEL FLOW IS EXPECTED TO GRADUALLY VEER TOWARD THE WEST THROUGH THE COURSE OF THE DAY AS THIS BOUNDARY CONTINUES SOUTH. THIS FLOW COMBINED WITH THE AFTERNOON EAST COAST SEA BREEZE...A COUPLE OF IMPULSES ALOFT AND MODERATE INSTABILITY AND SHEAR (0-6KM 30-35 KT) COULD GENERATE A FEW STRONG TO EVEN SEVERE THUNDERSTORMS THROUGH THE AFTERNOON/EVENING PERIOD TODAY OVER THE METRO/EAST COAST LOCATIONS. THE LATEST WRF AND HRRR MODEL REFLECTIVITIES... HOWEVER...ARE ONLY INDICATING ISOLATED COVERAGE OVER THESE AREAS AT BEST THROUGH THIS TIME. ANY STORMS THAT DO INITIATE COULD BE CAPABLE OF PRODUCING STRONG WINDS, HAIL AND POSSIBLY A TORNADO. THE LATEST FORECAST HAS BEEN UPDATED TO REFLECT THIS POTENTIAL THIS AFTERNOON. ELSEWHERE...VISIBILITIES HAVE BEGUN TO IMPROVE OVER THE PAST HOUR ACROSS THE INTERIOR LOCATIONS FROM THE EARLY MORNING FOG AND THIS TREND IS EXPECTED TO CONTINUE. THE LOCAL OFFICIALS HAVE REPORTED THAT SEGMENTS OF I-75 HAVE BEEN CLOSED TODAY DUE TO A COMBINATION OF THIS FOG EARLIER AND SMOKE FROM THE ONGOING WILDFIRE IN COLLIER COUNTY. && .PREV DISCUSSION... /ISSUED 739 AM EDT MON APR 1 2013/ AVIATION... AN UPPER LEVEL SHORTWAVE ACROSS THE EASTERN GULF WILL MOVE ACROSS THE FLORIDA PENINSULA TODAY. A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MAINLY TO THE EAST OF THE EAST COAST TAF SITES THIS MORNING. SEA BREEZE BOUNDARIES EARLY THIS AFTERNOON ARE EXPECTED TO HELP GENERATE SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS NEAR THE EAST COAST TAF SITES. SO ADDED VCTS FOR THE EAST COAST TAFS. FOR KAPF...THERE IS A SLIGHT CHANCE OF SHOWERS AHEAD OF THE TROUGH...MAINLY BEFORE 18Z. WIND DIRECTION MAY VARY BETWEEN 160-210 DEGREES DURING THE DAY AT THE EAST COAST TAF SITES. WINDS WILL SHIFT TO THE WEST TO NORTHWEST TONIGHT BEHIND THE BOUNDARY. PREV DISCUSSION... /ISSUED 459 AM EDT MON APR 1 2013/ DISCUSSION... CURRENTLY, A MID LEVEL TROUGH, ROUGHLY AT 700 MB, IS MOVING ACROSS THE EASTERN GULF OF MEXICO. THIS HAS GENERATED A LINE OF THUNDERSTORMS THAT IS EXPECTED TO FALL APART AS IT APPROACHES CENTRAL FLORIDA. THIS TROUGH, ACCORDING TO THE HRRR, MAY SPARK OFF A FEW SHOWERS OVER SOUTH FLORIDA THIS MORNING. ALSO, ANOTHER SHORT WAVE HAS GENERATED SOME SHOWERS AND ISOLATED THUNDERSTORMS OVER THE FLORIDA STRAITS. THESE ARE MOVING NORTH NORTHEAST. THE SHOWERS WILL AFFECT THE SOUTHEASTERN PORTION OF THE CWA THIS MORNING. THE QUESTION IS IF THERE WILL BE ANY THUNDERSTORMS THAT MOVE INTO THE AREA AS WELL. THERE IS AROUND 1000 JOULES JUST ONSHORE, AROUND HOMESTEAD AND MIAMI. SO, ALTHOUGH ORIGINAL THINKING WAS THEY WOULD STAY OFFSHORE, MAY HAVE TO ADD A MENTION OF THUNDERSTORMS FOR THIS AREA THIS MORNING. AS FOR LATER TODAY, MODELS INDICATE THE TROUGH, OR REALLY, A WEAKENING FRONT, WILL MOVE ONSHORE THE GULF COAST LATER THIS MORNING. MODELS ARE INDICATING IT WILL NOT BE TOO ACTIVE, CONVECTION WISE WHEN IT DOES. BUT, AS IT PROGRESS ACROSS THE STATE, ALONG WITH DAYTIME HEATING, CONVECTION MAY BE ABLE TO INITIATE. THE MODELS DO DIFFER GREATLY WITH HOW MUCH CAPE WILL BE AVAILABLE. THE GFS KEEPS THE HIGHEST BOUNDARY LAYER CAPE VALUES WELL OFFSHORE AND ONLY 500-600 JOULES OVER THE ATLANTIC COAST. THE NAM, ON THE OTHER HAND, HAS 1200 TO 1600 JOULES OVER THE ATLANTIC COAST, NEAT WEST PALM BEACH, AND DROPS TO 500-700 JOULES NEAR MIAMI. NOW THE NAM MODEL SOUNDINGS HAVE 1200-1600 JOULES ALL OVER THE ATLANTIC COAST. THEY DO SHOW A WEAK CAP FURTHER NORTH, BUT IT IS SO WEAK, NOT THINKING IT WILL BE A REAL INHIBITOR. THERE IS ALSO A TOUCH OF CIN TO THE NORTH AS WELL, BUT AGAIN, NOTHING THAT REALLY SHOULD INHIBIT DEVELOPMENT. SO, WHAT WILL INHIBIT THEIR DEVELOPMENT. WELL, MODELS DO SHOW THAT THE CAPE WILL BE PUSHING OFF TO THE EAST, AHEAD OF THE TROUGH. SO, WE MAY BE LACKING THE LIFTING MECHANISM. IT MAY ARRIVE WELL AFTER THE CAPE HAS PUSHED OFF SHORE. SO, HAVE KEPT CHC POPS AND SLIGHT CHC TSTMS, BUT HAVE BROADENED THE COVERAGE OF TSTMS THIS AFTERNOON. BEHIND THE TROUGH TODAY, HIGH PRESSURE WILL BE BUILDING IN FAIRLY QUICK. THIS WILL BRING QUIET WEATHER BACK TO SOUTH FLORIDA FOR A FEW DAYS. FOR FRIDAY AND THE WEEKEND, A LOW PRESSURE SYSTEM WILL DEVELOP OVER THE WESTERN GULF AND MOVE OVER THE FLORIDA PANHANDLE THURSDAY NIGHT/FRIDAY MORNING. A COLD FRONT WILL MOVE THROUGH SOUTH FLORIDA FRIDAY. THIS SYSTEM WILL BRING OUR NEXT CHANCE FOR RAIN AND POSSIBLY A THUNDERSTORM. MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE STRENGTH, POSITION, AND TIMING OF THIS SYSTEM. GIVEN THIS, HAVE A HIGH CHC POP IN THE FORECAST FOR FRIDAY. BEHIND THE FRONT, HIGH PRESSURE WILL BUILD IN ONCE AGAIN. TEMPERATURES WILL NOT BE MUCH COOLER, ONLY A FEW DEGREES. THIS HIGH PRESSURE WILL LAST FOR THE REMAINDER OF THE EXTENDED FORECAST. MARINE... WINDS AHEAD OF A WEAK FRONT/TROUGH WILL PICK UP OUT OF THE SOUTH TO BETWEEN 13 AND 19 KTS OVER THE ATLANTIC WATERS. THEY SHOULD REMAIN BELOW 10 KTS OVER THE GULF WATERS. THE HIGHER WIND SPEEDS OVER THE ATLANTIC WATERS HAS PROMPTED A SMALL CRAFT SHOULD EXERCISE CAUTION STATEMENT FOR THIS AFTERNOON. SEAS TODAY WILL BE SUBSIDING SOMEWHAT, EVEN WITH THE WINDS, AND ARE EXPECTED TO BE 1 TO 3 FEET BY TOMORROW IN THE ATLANTIC WATERS. THE GULF WATERS WILL BE AROUND 1 FOOT FOR THE NEXT COUPLE OF DAYS. HIGH PRESSURE WILL BUILD IN BEGINNING TONIGHT. THIS WILL CAUSE WINDS TO WEAKEN SOME TONIGHT TO 7-10 KTS OVER THE ATLANTIC AND SHIFT THEM OUT OF THE NORTH TOMORROW. FIRE WEATHER... THE MAIN FIRE WEATHER CONCERN TODAY ARE THE SHIFTING WINDS. AN APPROACHING FRONT/TROUGH WILL CAUSE WINDS TO PICK UP SOME TODAY TO 10 TO 15 MPH OVER GLADES, HENDRY, AND INTERIOR COLLIER COUNTIES. THEY WILL BEGIN OUT OF THE SOUTHEAST, BUT TURN THROUGH THE DAY TO THE SOUTH, THEN SOUTHWEST BY EARLY AFTERNOON. BY THIS EVENING, THEY WILL BECOME WESTERLY BETWEEN 5 AND 10 MPH. ALONG WITH THIS WIND SHIFT, WILL BE THE CHANCE FOR SOME RAIN SHOWERS AND A SLIGHT CHANCE FOR A THUNDERSTORM. THE CHANCES INCREASE AS YOU GO EASTWARD ACROSS SOUTH FLORIDA. IN THE INTERIOR PORTION OF THE AREA, THE DIVIDING LINE FOR THE CHANCE OF AND THUNDERSTORMS IS A DIFFICULT ONE AT BEST. SO, AREAS WEST OF THE FORECASTED AREA, SHOULD REMAIN AWARE OF THE POSSIBILITY THAT THE FORECAST COULD CHANGE TO INCLUDE THEM AS THE TROUGH GETS CLOSER. ONE THE OTHER HAND, IT COULD ALSO BE PUSHED FURTHER EAST. THERE IS JUST GREAT UNCERTAINTY WITH THE CONVECTIVE DEVELOPMENT TODAY. BEHIND THE TROUGH, HIGH PRESSURE WILL BUILD IN THROUGH THURSDAY, BRINGING QUIET WEATHER BACK TO SOUTH FLORIDA. PREV DISCUSSION... /ISSUED 241 AM EDT MON APR 1 2013/ AVIATION... ISOLATED SHOWERS WERE MOVING ACROSS THE ATLANTIC WATERS AND NEAR KFLL AND FXE. ANOTHER AREA OF SHOWERS AND EMBEDDED THUNDERSTORMS WERE MOVING JUST SOUTH OF THE KEYS. THIS AREA OF SHOWERS AND STORMS WILL CONTINUE TO MOVE NORTHWARD OVERNIGHT...AND COULD GET NEAR KTMB AND KMIA IN THE NEXT FEW HOURS IF THEY HOLD TOGETHER. A SHORTWAVE TROUGH MOVING ACROSS THE EASTERN GULF WAS FORCING SHOWERS AND THUNDERSTORMS TO DEVELOP WEST OF TAMPA. THE HRRR KEEPS THIS LINE TOGETHER AND MOVES IT TOWARDS KAPF AROUND 16Z. OTHER SHOWERS OR STORMS COULD ALSO BEGIN DEVELOPING ON THE EAST COAST SEA BREEZE AROUND THIS TIME. THE WIND DIRECTION IS ALSO TRICKY TODAY AS THE BOUNDARY LAYER WINDS SHIFT TO THE SOUTHWEST AHEAD OF THE TROUGH AND WEAK COLD FRONT. SO THE WINDS MAY SHIFT TO THE SOUTHWEST FOR A TIME LATE IN THE MORNING BEFORE THE EAST COAST SEA BREEZE BOUNDARY TRIES TO PUSH THE WINDS BACK TO THE SOUTH OR SOUTHEAST. BY 00Z...SOUTHWESTERLY FLOW IS EXPECTED TO PREVAIL...WITH WEST TO NORTHWESTERLY FLOW BEHIND THE SURFACE TROUGH AFTER 02-04Z. SO FOR THE TAFS...KEPT VCSH FOR NOW...BUT MAY NEED TO ADD VCTS. MVFR CONDITIONS ARE POSSIBLE NEAR ANY SHOWERS OR STORMS THAT FORM. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 82 65 81 68 / 50 20 10 - FORT LAUDERDALE 82 66 82 69 / 50 20 10 - MIAMI 82 67 83 69 / 50 20 10 - NAPLES 79 63 79 63 / 20 10 10 - && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...85/AG AVIATION/RADAR...60/BD
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
350 PM EDT MON APR 1 2013 ...BRIEF DRY PERIOD BEFORE RAIN RETURNS MID WEEK... .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... LATEST SURFACE ANALYSIS SHOWS SEMI PERMANENT SURFACE TROUGH FROM JUST SOUTH OF ATHENS THROUGH COLUMBUS. ALONG AND SOUTH OF THIS FEATURE MOISTURE SURFACE CONVERGENCE HAS RESULTED IN SCATTERED TO BROKEN CU DEVELOPMENT BUT SHOWER ACTIVITY HAS REMAINED OUTSIDE OF THE FORECAST AREA. FURTHER NORTH...SURFACE FRONT CONTINUES TO SAG INTO NORTH GA WITH MOISTURE POOLING ALONG ITS LEADING EDGE AS WELL AND ADDITIONAL CLOUD DEVELOPMENT THE RESULT. THIS SHOULD REMAIN JUST CLOUDS WITH NO PRECIP FOR THIS EVENING AS MAIN FOCUS WILL BE ON SOUTHERN TROUGH AND IT AFFECTS ON CENTRAL GEORGIA. LOOKING AT THE LATEST RAP ANALYSIS OF CAPE IN THIS VICINITY AND WE SEE 500 J/KG TO 1000 J/KG OF AVAILABLE ENERGY...SLIGHTLY HIGHER THAN MODEL PROJECTIONS. STILL LOOKING AT 500MN TEMPS IN THE VERY COLD RANGE OF -17C IN THIS AREA SO ANY SUSTAINED UPDRAFTS WILL BE CAPABLE OF PRODUCING LARGE HAIL. ACTIVITY WILL SHIFT EAST QUICKLY THIS EVENING WITH CLEARING CONDITIONS TAKING PLACE. STILL SOME GRADIENT IN PLACE ACROSS THE AREA WHICH WILL PREVENT OPTIMUM RADIATIONAL COOLING CONDITIONS. WENT WITH A MAV/MET BLEND FOR THE OVERNIGHT TEMPS WHICH WILL BE TRICKY TO THE SOUTH BASED ON HOW FAST CLOUDS CLEAR. SURFACE FRONT LOOKS TO STALL ACROSS NORTH GEORGIA TUESDAY AND IMPULSES OF ENERGY BEGIN TO ROUND PERIPHERY OF EAST COAST TROUGH. THIS SHOULD ALLOW A FEW LIGHT SHOWERS TO DEVELOP ACROSS EXTREME NORTH GEORGIA AND HAVE INCLUDED IN THIS GRID PACKAGE. AS HIGH BRIDGES ACROSS THROUGH TUESDAY NIGHT...MAY SEE FRONT SAG FURTHER SOUTH AND TAKE 20 POPS ALONG WITH IT INTO THE REMAINDER OF NORTH GEORGIA. DEESE .LONG TERM /WEDNESDAY THROUGH MONDAY/... MAIN CONCERN FOR THE EXTENDED REMAINS THE SYSTEM MOVING THROUGH THE STATE ON WEDNESDAY INTO THE END OF THE WORK WEEK. DISCREPANCIES STILL REMAIN BETWEEN THE EURO AND GFS AS FAR AS TIMING OF THE SYSTEM LEAVING THE CWA. THE 12Z MODELS ARE STRIKINGLY SIMILAR TO THEIR OOZ COUNTERPARTS. AS SUCH...WAS NOT ABLE TO NAIL DOWN AN ACCURATE END TO THE RAIN THIS WEEK. ACCORDING TO HPC MODEL DISCUSSIONS THE EURO IS AN OUTLIER...MOVING THE SYSTEM FURTHER SOUTH AND IS SLOWER. THAT SAID THEY DECIDED TO WITH A BLEND BETWEEN THE 00Z EURO AND THE 06Z GEFS. WITH THIS MUCH UNCERTAINTY DECIDED TO ONLY CHANGE THE COVERAGE OF THUNDER ON WEDNESDAY AND LEAVE THE REST OF THE FORECAST ALONE. DID LOWER TEMPS ON THURSDAY AS A PSEUDO WEDGE BUILDS IN. CLOUDS AND RAIN IN ASSOCIATION WITH THIS WEDGE SHOULD HELP TO KEEP TEMPS LOW. HAVE INCLUDED PREVIOUS EXTENDED BELOW/ ARG && LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... POTENTIAL FOR A HEAVY RAIN/SEVERE WEATHER EVENT SETTING UP IN THE THURSDAY TO THURSDAY NIGHT TIME FRAME. MODELS SIMILAR WITH SPREADING DEEPER MOISTURE INTO THE AREA LATE WEDNESDAY BUT THE MAIN PRECIP PERIOD LOOKS TO BE WEDNESDAY NIGHT THRU THURSDAY NIGHT. AN OVERRUNNING PATTERN WILL SET LATE WEDNESDAY/WEDNESDAY NIGHT WITH MODELS DEVELOPING A WARM FRONT ALONG THE GULF COAST. SURFACE LOW PRESSURE DEVELOPS OVER THE WESTERN GULF AND MOVES TO THE WESTERN FL PANHANDLE LATE THURSDAY AND THEN ACROSS CENTRAL TO S GA THURSDAY NIGHT/FRIDAY. THE GFS IS FASTER WITH THIS PROGRESSION THAN THE EUROPEAN. THIS TRACK COULD MOVE THE WARM FRONT INTO THE SE CWA AND GIVE POTENTIAL FOR SEVERE THUNDERSTORMS MAINLY THURSDAY NIGHT. IT WILL ALSO GIVE POTENTIAL FOR HEAVY RAIN ACROSS A LARGE PORTION OF EAST GEORGIA AND MODELS IN GENERAL ARE LESS GUN-OH WITH PRECIP AMOUNTS WITH A LARGE AREA OF 1-2 INCHES FORECAST. THE UPPER TROUGH MOVES ACROSS THE AREA ON FRIDAY AND THE GFS IS FASTER WITH THIS PROGRESSION THAN THE EUROPEAN. THE AIRMASS DRIES OUT FOR SATURDAY AND MOSTLY LIKELY SUNDAY WITH THE EUROPEAN INDICATING SOME MOISTURE ASSOCIATED WITH A SHORT WAVE ON SUNDAY...MOST SO FOR N GA. FOR NOW WILL KEEP THINGS DRY AND MONITOR THE PROGRESSION. A SHORT WAVE RIDGE BUILDS FOR MONDAY WITH THE EUROPEAN CONTINUING TO SHOW MORE MOISTURE SKIRTING OVER N GA THAN THE GFS. BDL AVIATION... 18Z UPDATE... VFR FORECAST IN STORE AS MAIN CLOUD SHIELD HAS SLIPPED TO THE SOUTH OF THE TERMINALS. WILL BE WATCHING SECONDARY AREA OF CLOUDS DEVELOPING OVER EXTREME NORTH GA IN ENHANCED MOISTURE ZONE BUT JUST PLAYING AS FEW050 FOR NOW. OTHERWISE...STILL UNCERTAINTY WITH WIND SHIFT POTENTIAL MID MORNING TUESDAY WITH NW VS NE STILL IN QUESTION FOR ATL. WENT WITH CONSENSUS OF NW FOR NOW WHICH AGREES WITH PARTNERS AND CONSENSUS. //ATL CONFIDENCE...18Z UPDATE... MEDIUM ON WIND SHIFT. HIGH ON REMAINING ELEMENTS. DEESE && .PRELIMINARY POINT TEMPS/POPS... ATHENS 42 69 41 64 / 10 10 20 20 ATLANTA 47 67 44 64 / 5 5 20 20 BLAIRSVILLE 37 58 35 63 / 10 10 20 20 CARTERSVILLE 41 65 40 64 / 5 10 20 20 COLUMBUS 51 75 50 70 / 5 5 5 30 GAINESVILLE 44 65 43 61 / 10 10 20 20 MACON 45 75 44 69 / 5 5 5 30 ROME 38 65 38 64 / 5 10 20 20 PEACHTREE CITY 40 70 42 65 / 5 5 20 30 VIDALIA 55 76 51 74 / 20 0 5 20 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DEESE LONG TERM....ARG AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
126 AM EDT MON APR 1 2013 .SYNOPSIS... ATLANTIC HIGH PRESSURE WILL PREVAIL OVERNIGHT. A COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY AFTERNOON INTO MONDAY EVENING...FOLLOWED BY HIGH PRESSURE BUILDING FROM THE NORTH THROUGH THE MIDDLE OF THE WEEK. A LOW PRESSURE SYSTEM WILL THEN PASS ALONG THE SOUTHEAST COAST LATE IN THE WEEK INTO EARLY NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... UPSTREAM PCPN TRENDS AND LATEST RAP MODEL DATA HAVE TRENDED A BIT SLOWER WITH RAIN REACHING THE I-95 CORRIDOR THROUGH 6 AM. WE KNOCKED BACK POPS ALONG AND E OF I-95 DOWN ON THE MIDNIGHT UPDATE. TEMPS WILL BE NO LOWER THAN THE UPPER 50S AND LOWER 60S...MAKING THEM THE WARMEST NIGHT TIME LOWS IN MANY LOCALES SINCE FEBRUARY 11TH. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... MONDAY...A COLD FRONT WILL BE SITUATED ACROSS THE SOUTH CAROLINA MIDLANDS AND EAST-CENTRAL GEORGIA TO START THE DAY...WITH AN AXIS OF DEEP MOISTURE IN PLACE OVER THE AREA AHEAD OF THE FRONT WHERE PRECIPITABLE WATER VALUES WILL PEAK AROUND 1.3 TO 1.4 INCHES. THE DEEP MOISTURE COMBINED WITH FORCING FROM THE RIGHT ENTRANCE REGION OF A WEAKENING H25 JET WILL SUPPORT NUMEROUS SHOWERS ACROSS THE AREA IN THE MORNING. THE SHOWERS WILL THEN BEGIN TO TAPER OFF FROM THE WEST DURING THE AFTERNOON AS THE FRONT SHIFTS ACROSS THE AREA AND OFFSHORE BY LATE IN THE DAY. SOME THUNDERSTORMS ARE POSSIBLE...A FEW OF WHICH COULD BE STRONG/SEVERE AT TIMES WITH SURFACE BASED CAPE VALUES OF 800-1000 J/KG AND...LI VALUES OF -3C TO -5C AND MID LEVEL LAPSE RATES OF 6-7 C/KM. WET BULB ZERO HEIGHTS POSSIBLY REACHING AS LOW AS 8-9K FT WILL SUPPORT A HAIL THREAT...WITH DAMAGING WINDS ALSO POSSIBLE. THE GREATEST POTENTIAL FOR ANY STRONG/SEVERE THUNDERSTORMS APPEARS TO BE ACROSS SOUTHEAST GEORGIA...BUT GIVEN UNCERTAINTY IN THE EXTENT OF DIURNAL HEATING THAT CAN TAKE PLACE DUE TO EXTENSIVE CLOUD COVER AND PRECIPITATION...WILL KEEP MENTION OUT OF THE HAZARDOUS WEATHER OUTLOOK FOR NOW. DESPITE THE EXTENSIVE CLOUD COVER INITIALLY...A GOOD SOUTHWEST FLOW AND WEAK COMPRESSIONAL HEATING AHEAD OF THE FRONT FOLLOWED BY A WARM WESTERLY FLOW IN ITS WAKE SHOULD ALLOW TEMPERATURES TO REACH HIGHS IN THE MID 70S ACROSS THE AREA AWAY FROM THE COOLER IMMEDIATE COAST. MONDAY NIGHT...A SECONDARY COLD FRONT WILL SWING THROUGH THE AREA DURING THE EVENING...WITH A DEVELOPING NORTHWEST/NORTH FLOW ADVECTING A DRIER AIRMASS INTO THE REGION. ANY LINGERING ISOLATED SHOWERS EARLY IN THE EVENING WILL QUICKLY COME TO AN END...WITH MOSTLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED THROUGH THE REMAINDER OF THE NIGHT. LOW TEMPERATURES WILL BE IN THE UPPER 40S TO LOWER 50S. TUESDAY AND TUESDAY NIGHT...A WEAK BUBBLE HIGH WILL SETTLE OVER THE CAROLINAS WITH A NEARLY ZONAL FLOW IN PLACE ALOFT. RAIN-FREE CONDITIONS AND PARTLY CLOUDY SKIES ARE EXPECTED. A WEAK DOWNSLOPE FLOW ALOFT SHOULD HELP TEMPERATURES REACHES HIGH ON TUESDAY IN THE LOWER TO MID 70S ACROSS MUCH OF THE AREA AWAY FROM THE IMMEDIATE COAST...WITH SOME UPPER 70S EVEN POSSIBLE SOUTH OF THE I-16 CORRIDOR. LOWS TUESDAY NIGHT WILL BE IN THE UPPER 40S TO LOWER 50S ONCE AGAIN. WEDNESDAY...IT APPEARS THAT A WEAK BACKDOOR COLD FRONT DROPS THROUGH THE AREA IN RESPONSE TO A STRONGER WEDGE OF HIGH PRESSURE BUILDING FROM THE NORTH. THERE IS SOME MODEL DISAGREEMENT WITH RESPECT TO THE EXTENT OF MOISTURE ACCOMPANYING THE BUILDING WEDGE...WITH THE NAM MUCH MORE AGGRESSIVE THAN THE OTHER MODELS. WHILE THE CONSENSUS IS FOR NOT MUCH IN THE WAY OF RAINFALL STILL FEEL THAN AN ISOLATED SHOWER CANNOT BE RULED OUT AND THE FORECAST INDICATES A SLIGHT CHANCE OF RAIN AS A RESULT. THE TEMPERATURE FORECAST IS ALSO TRICKY AND THERE WILL LIKELY BE A LARGE GRADIENT ACROSS THE AREA...BUT FEEL THE SAFEST BET IS TO FORECAST HIGHS RANGING FROM THE LOWER AND MID 60S IN SOUTHEAST SOUTH CAROLINA TO THE UPPER 60S AND LOWER 70S IN SOUTHEAST GEORGIA. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... WEDNESDAY NIGHT THROUGH FRIDAY...WE WILL SEE A TRANSITION TO A MUCH WETTER PATTERN AS A SFC LOW DEEPENS OVER THE NORTHERN GULF WHILE AN H5 SHORTWAVE DIGS OVER THE DEEP SOUTH. PRECIP CHANCES WILL INCREASE IN SOUTHEAST GEORGIA..THEN INTO SOUTHEAST SOUTH CAROLINA AS AN EASTWARD EXTENDING WARM FRONT DEVELOPS WEDNESDAY NIGHT AND BECOMES POSITIONED ALONG THE SOUTHEAST COAST THURSDAY. THE AMOUNT OF RAINFALL ASSOCIATED WITH THIS SYSTEM WILL BE HIGHLY DEPENDENT ON THE POSITION OF THE WARM FRONT AND THE TRACK OF THE SFC LOW FROM THE NORTHERN GULF OF MEXICO TO THE SOUTHEAST COAST. AT THIS TIME...HIGH PRESSURE LOOKS TO MAINTAIN SOME HOLD OVER THE FORECAST AREA...THUS FORCING A MORE SOUTHERN TRACK OF THE SFC LOW OVER NORTHERN FLORIDA AND THEN ALONG THE SOUTHEAST COAST. WITH THIS TRACK IN MIND...HAVE INTRODUCED LIKELY POPS OVER SOUTHEAST GEORGIA AND CHANCE POPS OVER SOUTHEAST SOUTH CAROLINA WEDNESDAY NIGHT...WITH LIKELY POPS ACROSS THE AREA THURSDAY AND THURSDAY NIGHT BEFORE THE SFC LOW RAPIDLY DEEPENS AND SHIFTS TO THE NORTHEAST FRIDAY. SHOULD A MORE NORTHERN TRACK TAKE PLACE...A CHANCE OF THUNDERSTORMS WILL LIKELY NEED TO BE INTRODUCED OVER THE AREA. OVERALL TEMPS SHOULD REMAIN COOL ON THURSDAY WITH HIGH PRESSURE MAINTAINING A HOLD. OVERALL TEMPS SHOULD RANGE BETWEEN THE UPPER 50S NORTH...TO LOW/MID 60S SOUTH. BY FRIDAY...TEMPS SHOULD MODIFY A FEW DEGREES WITH THE WARM FRONT ALONG THE COAST. OVERNIGHT LOWS SHOULD REACH THE LOW/MID 40S WEDNESDAY NIGHT AND UPPER 40S TO LOWER 50S THURSDAY AND FRIDAY NIGHT. SATURDAY AND SUNDAY...A DRY AND WARMING TREND IS ANTICIPATED FOR THE SECOND HALF OF THE WEEKEND AS MID LVL RIDGING GRADUALLY EXPANDS INTO THE SOUTHEAST. WITH LITTLE CLOUD ANTICIPATED...OVERALL TEMPS SHOULD REACH THE UPPER 60S TO LOWER 70S SATURDAY AND LOWER 70S OVER MOST LOCATIONS ON SUNDAY. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... OVERNIGHT WE HAVE MAINTAINED VFR WITH DRY WEATHER AT KSAV AND KCHS. LATEST MODEL GUIDANCE SUGGESTS THE BEST TIMING FOR SCATTERED SHOWERS WILL BE FROM 8 AM TO ABOUT NOON TODAY. TSTMS ARE POSSIBLE BUT TOO EARLY/UNCERTAIN TO INTRO TSRA/CB AT THIS TIME. THIS AFTERNOON...WEST WINDS WILL DIMINISH RAIN CHANCES AND MVFR CIG POTENTIAL BUT WILL HAVE TO WATCH FOR ISOLATED TSTMS AHEAD OF THE COLD FRONT. AFTER SUNSET...VFR CONDITIONS TO ALSO PREVAIL. EXTENDED AVIATION OUTLOOK...VFR CONDITIONS SHOULD PREVAIL THROUGH WEDNESDAY. MVFR OR LOWER CIGS/VSBYS ARE POSSIBLE WEDNESDAY NIGHT THROUGH FRIDAY MORNING DUE TO RAIN/SHOWERS ASSOCIATED WITH A SFC LOW TRACKING OVER NORTHERN FLORIDA AND THEN ALONG THE SOUTHEAST COAST. && .MARINE... OVERNIGHT...THE COASTAL WATERS WILL BE SITUATED UNDER THE NW FRINGES OF ATLANTIC RIDGING...WITH AN UPSTREAM COLD FRONT OVER THE SE UNITED STATES. THE PRESSURE GRADIENT BETWEEN THESE TWO SYNOPTIC FEATURES WILL BE TIGHT ENOUGH WHERE SOUTH AND SW WINDS WILL REMAIN ELEVATED. SPEEDS WILL BE A SOLID 15 OR 20 KT OVER THE OCEAN...WITH FREQUENT GUSTS OF 25 KT ACROSS THE OUTER GA WATERS. IT IS THERE WHERE WE HAVE MAINTAINED THE SCA. IN CHARLESTON HARBOR WINDS WILL GENERALLY HOLD UNDER 15 KT. DUE TO THESE WINDS AND A SOMEWHAT FAVORABLE FETCH...SEAS WILL BE AS HIGH AS 3-5 FT WITHIN 20 NM OF THE SHORE...BUT 4-6 FT ACROSS THE GA WATERS 20-60 NM OUT. MONDAY THROUGH FRIDAY...SOUTHWEST FLOW WILL PREVAIL AHEAD OF AN APPROACHING COLD FRONT MONDAY...WITH A TIGHT SURFACE PRESSURE GRADIENT SUPPORTING MARGINAL SMALL CRAFT ADVISORY CONDITIONS OVER PORTIONS OF THE OUTER GEORGIA WATERS DURING THE MORNING. CONDITIONS WILL IMPROVE FOLLOWING THE PASSAGE OF A COLD FRONT MONDAY EVENING AS WINDS SHIFT OFFSHORE. BUILDING HIGH PRESSURE WILL ALLOW A NORTHEAST SURGE TO DEVELOP LATE MONDAY NIGHT INTO TUESDAY...WITH WINDS PEAKING AROUND 15-20 KT. WEAK HIGH PRESSURE OVER THE CAROLINAS WILL THEN KEEP CONDITIONS RATHER BENIGN OVER THE WATERS THROUGH TUESDAY NIGHT. A WEAK BACK DOOR COLD FRONT WILL DROP THROUGH AS STRONGER HIGH PRESSURE BUILDS FROM THE NORTH ON WEDNESDAY...CAUSING WINDS/SEAS TO BEGIN DETERIORATING LATE WEDNESDAY AND WEDNESDAY NIGHT. SMALL CRAFT ADVISORY CONDITIONS ARE THEN LIKELY LATE WEEK AS CONDITIONS DETERIORATE FURTHER DUE TO AN ENHANCED PRESSURE GRADIENT BETWEEN HIGH PRESSURE OVER THE WESTERN ATLANTIC AND LOW PRESSURE OVER THE NORTHERN GULF ON THURSDAY FOLLOWED BY THE PASSAGE OF A COASTAL LOW ALONG THE SOUTHEAST COAST THURSDAY NIGHT INTO FRIDAY. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR AMZ374. && $$ SYNOPSIS... NEAR TERM... SHORT TERM...JAQ LONG TERM...DPB/JAQ AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
635 AM EDT MON APR 1 2013 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 353 AM EDT MON APR 1 2013 A WEAK UPPER WAVE WILL MOVE THROUGH THE AREA THIS MORNING BUT HIGH PRESSURE WILL BUILD IN THIS AFTERNOON AND KEEP DRY WEATHER ACROSS THE AREA THROUGH SATURDAY. SATURDAY NIGHT A LOW PRESSURE SYSTEM WILL APPROACH AND BRING CHANCES FOR RAIN. TEMPERATURES WILL BE WELL BELOW NORMAL TODAY THROUGH TUESDAY NIGHT AND THEN REBOUND TO ABOVE NORMAL BY THE WEEKEND. && .NEAR TERM /TODAY/... ISSUED AT 353 AM EDT MON APR 1 2013 FORECAST FOCUS IS ON NEED FOR ANY POPS FROM EARLY TO MID MORNING. UPPER WAVE IS CURRENTLY MOVING SOUTHEAST THROUGH SOUTHERN IOWA AND WESTERN ILLINOIS. RADAR MOSAIC SHOWS WEAK ECHOES OVER WESTERN AND CENTRAL ILLINOIS AS WELL AS SOME ENTERING WESTERN INDIANA BUT SURFACE OBS SHOW NO PRECIP AT THE GROUND. GFS AND NAM ARE BOTH DRY AND GUIDANCE IS AS WELL. RAPID REFRESH AND RAP SHOW SOME DEVELOPMENT OCCURRING ACROSS THE SOUTHERN COUNTIES AROUND 11-12Z AND MOVING THROUGH BY 15Z. WITH BOTH OF THE RAPID UPDATE MODELS SHOWING THIS DEVELOPMENT WILL GO AHEAD AND LEAVE A SLIGHT CHANCE FOR RAIN AND SNOW MOVING ACROSS THE SOUTH FROM 11 TO 15Z AND DRY FROM 15Z ON. SHOULD NOT AMOUNT TO ANYTHING. WILL DROP ANY MENTION OF FLURRIES ELSEWHERE. CLOUDS SHOULD SCATTER OUT AS THE DAY GOES ON. WILL SEE COLD ADVECTION THROUGHOUT THE DAY SO TEMPERATURES SHOULD STRUGGLE TO WARM AND THUS WENT WITH A CONSENSUS OF RAW MODEL NUMBERS SINCE CLIMATOLOGY COULD BIAS THINGS UP. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 353 AM EDT MON APR 1 2013 HIGH PRESSURE WILL DOMINATE THE WEATHER IN THE SHORT TERM. MODELS ARE IN GOOD AGREEMENT AND WILL USE A CONSENSUS. WITH MOSTLY CLEAR TO CLEAR SKIES THROUGHOUT THE SHORT TERM STUCK CLOSE TO COOLER GUIDANCE NUMBERS AT NIGHT OF LOW TO MIDDLE 20S. FOR HIGHS TUESDAY AGAIN THOUGHT GUIDANCE WAS BIASED A BIT WARM FROM CLIMATOLOGY SO STUCK WITH A RAW MODEL CONSENSUS IN THE LOW TO MID 40S...BUT BY WEDNESDAY THE AIR MASS SHOULD BE REBOUNDING UNDER WARM ADVECTION AND A COMPLETE CONSENSUS LOOKED GOOD IN THE UPPER 40S TO LOW 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 324 AM EDT MON APR 1 2013 A LARGE AREA OF HIGH PRESSURE WILL BE MOVING AWAY TO THE EAST ON THURSDAY WITH A SPLIT FLOW PATTERN ALOFT AS A WEAK FRONT APPROACHES FROM THE NORTHWEST AND AN UPPER LOW TRACKS ACROSS THE SOUTHERN PLAINS. MODEL CONSENSUS HAS BEEN TRACKING THE UPPER WAVE FURTHER NORTH OVER THE LAST COUPLE DAYS AND BRINGS THE NORTHERN FRINGES OF THE RAINFALL ASSOCIATED WITH THE UPPER LOW INTO THE OHIO RIVER VALLEY THURSDAY NIGHT. CONSIDERING THE NORTHERLY LOW LEVEL FLOW...PRESENCE OF DRIER AIR OVER THE REGION AND THE BULK OF THE DEEPER FORCING REMAINING TO THE SOUTH OF THE FORECAST AREA...WILL CONTINUE TO KEEP A DRY FORECAST GOING THURSDAY NIGHT. DO ANTICIPATE AN INCREASE IN CLOUDS OVER THE SOUTHERN COUNTIES THURSDAY NIGHT AND EARLY FRIDAY AS THE UPPER WAVE PASSES TO THE SOUTH. THE AFOREMENTIONED WEAK FRONT APPROACHING FROM THE NORTHWEST SET TO WASH OUT ACROSS THE LOWER GREAT LAKES THURSDAY NIGHT. AS THE UPPER WAVE WEAKENS AND SHIFTS INTO THE SOUTHEAST STATES BY FRIDAY AFTERNOON...HIGH PRESSURE WILL REESTABLISH ACROSS THE OHIO VALLEY WITH AN EXPANSION OF RIDGING ALOFT BRINGING WARMER AIR INTO THE REGION. LOW LEVEL THERMALS SUPPORT HIGH TEMPS RISING INTO THE 60S BY SATURDAY. FORECAST MORE MUDDLED FOR THE SECOND HALF OF THE WEEKEND AS A DEVELOPING WARM FRONT SETS UP OVER THE LOWER GREAT LAKES AND A SURFACE WAVE TRACKS ALONG THE BOUNDARY ON SUNDAY. WILL CARRY LOW CHANCE POPS SATURDAY NIGHT INTO SUNDAY AS THE SURFACE WAVE PASSES THROUGH THE AREA. APPEARS THE BOUNDARY MAY SETTLE FURTHER SOUTH NEAR THE OHIO RIVER BY LATE SUNDAY WITH THE PASSAGE OF THE LOW...BEFORE THE BOUNDARY RETURNS BACK NORTH EARLY NEXT WEEK. LOW LEVEL THERMALS STILL SUGGESTIVE OF HIGHS IN THE 60S FOR SUNDAY EVEN AS THE BOUNDARY SHIFTS SOUTH...WITH POSSIBILITY FOR WARMER DAYTIME HIGHS EARLY NEXT WEEK ONCE THE FRONT LIFTS BACK NORTH. && .AVIATION /DISCUSSION FOR 011200Z TAF ISSUANCE/... ISSUED AT 635 AM EDT MON APR 1 2013 VFR CONDITIONS ANTICIPATED THROUGHOUT THE FORECAST PERIOD. MID LEVEL CLOUDS PRESENT EARLY THIS MORNING AS AN UPPER WAVE MOVES THROUGH THE REGION. AREA OF RETURNS NOTED FROM WESTERN INDIANA BACK INTO ILLINOIS BUT APPEARS LITTLE IF ANY OF THIS IS REACHING THE GROUND BASED ON CURRENT OBS. MAY SEE A FEW FLURRIES AT KBMG/KHUF/KIND THROUGH 15Z BUT EXPECT NO IMPACTS TO TERMINALS. MODEL SOUNDINGS SHOW FAVORABLE CONDITIONS FOR CU DEVELOPMENT THIS AFTERNOON WITH CONVECTIVE TEMPS IN THE UPPER 30S AND INCREASING COLD ADVECTION. LIKELY TO SEE GUSTS TO AROUND 20KTS AS WELL THROUGH THE AFTERNOON WITH GOOD LOW LEVEL MIXING. AS HIGH PRESSURE SPREADS INCREASINGLY DRIER AIR INTO THE FORECAST AREA...WILL SEE A GRADUAL DECREASE IN CU BY LATE DAY WITH SKIES BECOMING MOSTLY CLEAR TONIGHT.NORTHWEST WINDS WILL BECOME LIGHT THIS EVENING. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
415 AM EDT MON APR 1 2013 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 353 AM EDT MON APR 1 2013 A WEAK UPPER WAVE WILL MOVE THROUGH THE AREA THIS MORNING BUT HIGH PRESSURE WILL BUILD IN THIS AFTERNOON AND KEEP DRY WEATHER ACROSS THE AREA THROUGH SATURDAY. SATURDAY NIGHT A LOW PRESSURE SYSTEM WILL APPROACH AND BRING CHANCES FOR RAIN. TEMPERATURES WILL BE WELL BELOW NORMAL TODAY THROUGH TUESDAY NIGHT AND THEN REBOUND TO ABOVE NORMAL BY THE WEEKEND. && .NEAR TERM /TODAY/... ISSUED AT 353 AM EDT MON APR 1 2013 FORECAST FOCUS IS ON NEED FOR ANY POPS FROM EARLY TO MID MORNING. UPPER WAVE IS CURRENTLY MOVING SOUTHEAST THROUGH SOUTHERN IOWA AND WESTERN ILLINOIS. RADAR MOSAIC SHOWS WEAK ECHOES OVER WESTERN AND CENTRAL ILLINOIS AS WELL AS SOME ENTERING WESTERN INDIANA BUT SURFACE OBS SHOW NO PRECIP AT THE GROUND. GFS AND NAM ARE BOTH DRY AND GUIDANCE IS AS WELL. RAPID REFRESH AND RAP SHOW SOME DEVELOPMENT OCCURRING ACROSS THE SOUTHERN COUNTIES AROUND 11-12Z AND MOVING THROUGH BY 15Z. WITH BOTH OF THE RAPID UPDATE MODELS SHOWING THIS DEVELOPMENT WILL GO AHEAD AND LEAVE A SLIGHT CHANCE FOR RAIN AND SNOW MOVING ACROSS THE SOUTH FROM 11 TO 15Z AND DRY FROM 15Z ON. SHOULD NOT AMOUNT TO ANYTHING. WILL DROP ANY MENTION OF FLURRIES ELSEWHERE. CLOUDS SHOULD SCATTER OUT AS THE DAY GOES ON. WILL SEE COLD ADVECTION THROUGHOUT THE DAY SO TEMPERATURES SHOULD STRUGGLE TO WARM AND THUS WENT WITH A CONSENSUS OF RAW MODEL NUMBERS SINCE CLIMATOLOGY COULD BIAS THINGS UP. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 353 AM EDT MON APR 1 2013 HIGH PRESSURE WILL DOMINATE THE WEATHER IN THE SHORT TERM. MODELS ARE IN GOOD AGREEMENT AND WILL USE A CONSENSUS. WITH MOSTLY CLEAR TO CLEAR SKIES THROUGHOUT THE SHORT TERM STUCK CLOSE TO COOLER GUIDANCE NUMBERS AT NIGHT OF LOW TO MIDDLE 20S. FOR HIGHS TUESDAY AGAIN THOUGHT GUIDANCE WAS BIASED A BIT WARM FROM CLIMATOLOGY SO STUCK WITH A RAW MODEL CONSENSUS IN THE LOW TO MID 40S...BUT BY WEDNESDAY THE AIR MASS SHOULD BE REBOUNDING UNDER WARM ADVECTION AND A COMPLETE CONSENSUS LOOKED GOOD IN THE UPPER 40S TO LOW 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 324 AM EDT MON APR 1 2013 A LARGE AREA OF HIGH PRESSURE WILL BE MOVING AWAY TO THE EAST ON THURSDAY WITH A SPLIT FLOW PATTERN ALOFT AS A WEAK FRONT APPROACHES FROM THE NORTHWEST AND AN UPPER LOW TRACKS ACROSS THE SOUTHERN PLAINS. MODEL CONSENSUS HAS BEEN TRACKING THE UPPER WAVE FURTHER NORTH OVER THE LAST COUPLE DAYS AND BRINGS THE NORTHERN FRINGES OF THE RAINFALL ASSOCIATED WITH THE UPPER LOW INTO THE OHIO RIVER VALLEY THURSDAY NIGHT. CONSIDERING THE NORTHERLY LOW LEVEL FLOW...PRESENCE OF DRIER AIR OVER THE REGION AND THE BULK OF THE DEEPER FORCING REMAINING TO THE SOUTH OF THE FORECAST AREA...WILL CONTINUE TO KEEP A DRY FORECAST GOING THURSDAY NIGHT. DO ANTICIPATE AN INCREASE IN CLOUDS OVER THE SOUTHERN COUNTIES THURSDAY NIGHT AND EARLY FRIDAY AS THE UPPER WAVE PASSES TO THE SOUTH. THE AFOREMENTIONED WEAK FRONT APPROACHING FROM THE NORTHWEST SET TO WASH OUT ACROSS THE LOWER GREAT LAKES THURSDAY NIGHT. AS THE UPPER WAVE WEAKENS AND SHIFTS INTO THE SOUTHEAST STATES BY FRIDAY AFTERNOON...HIGH PRESSURE WILL REESTABLISH ACROSS THE OHIO VALLEY WITH AN EXPANSION OF RIDGING ALOFT BRINGING WARMER AIR INTO THE REGION. LOW LEVEL THERMALS SUPPORT HIGH TEMPS RISING INTO THE 60S BY SATURDAY. FORECAST MORE MUDDLED FOR THE SECOND HALF OF THE WEEKEND AS A DEVELOPING WARM FRONT SETS UP OVER THE LOWER GREAT LAKES AND A SURFACE WAVE TRACKS ALONG THE BOUNDARY ON SUNDAY. WILL CARRY LOW CHANCE POPS SATURDAY NIGHT INTO SUNDAY AS THE SURFACE WAVE PASSES THROUGH THE AREA. APPEARS THE BOUNDARY MAY SETTLE FURTHER SOUTH NEAR THE OHIO RIVER BY LATE SUNDAY WITH THE PASSAGE OF THE LOW...BEFORE THE BOUNDARY RETURNS BACK NORTH EARLY NEXT WEEK. LOW LEVEL THERMALS STILL SUGGESTIVE OF HIGHS IN THE 60S FOR SUNDAY EVEN AS THE BOUNDARY SHIFTS SOUTH...WITH POSSIBILITY FOR WARMER DAYTIME HIGHS EARLY NEXT WEEK ONCE THE FRONT LIFTS BACK NORTH. && .AVIATION /DISCUSSION FOR THE 010900Z TAF UPDATE/... ISSUED AT 415 AM EDT MON APR 1 2013 MID LEVEL CLOUDS EXPANDING BACK ACROSS THE TERMINALS EARLY THIS MORNING AS THE UPPER TROUGH SHARPENS OVER THE REGION. TWEAKED CLOUDS AND WIND SPEEDS BASED ON CURRENT OBS WITH EXPECTATION OF SOME GUSTS APPROACHING 20KTS THROUGH THE MORNING. AREA OF SCATTERED LIGHT SNOW SHOWERS/FLURRIES OVER NORTHEAST MISSOURI AND WESTERN ILLINOIS WILL MOVE EAST TOWARDS THE REGION BY DAYBREAK. AT THIS POINT HOWEVER... STILL APPEARS THIS AREA OF PRECIP WILL CONTINUE TO WEAKEN WITH POSSIBILITY OF JUST A FEW FLURRIES AT KBMG/KHUF/KIND IN THE 12-15Z PERIOD. WILL MAINTAIN NO PRECIP MENTION IN TERMINALS AT THIS TIME. 06Z DISCUSSION FOLLOWS. VFR THROUGH THE PERIOD. SCT TO BKN MID CLOUD LIKELY THE ONLY SKY COVER THROUGH THE NIGHT. WINDS WILL ONCE AGAIN GUST TOMORROW TO NEAR 20KT...AND DIURNAL CUMULUS WILL FORM AROUND 5KFT. NO VISIBILITY ISSUES ANTICIPATED THROUGH THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...NIELD/RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
400 AM EDT MON APR 1 2013 .UPDATE... THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW && .SYNOPSIS... ISSUED AT 353 AM EDT MON APR 1 2013 A WEAK UPPER WAVE WILL MOVE THROUGH THE AREA THIS MORNING BUT HIGH PRESSURE WILL BUILD IN THIS AFTERNOON AND KEEP DRY WEATHER ACROSS THE AREA THROUGH SATURDAY. SATURDAY NIGHT A LOW PRESSURE SYSTEM WILL APPROACH AND BRING CHANCES FOR RAIN. TEMPERATURES WILL BE WELL BELOW NORMAL TODAY THROUGH TUESDAY NIGHT AND THEN REBOUND TO ABOVE NORMAL BY THE WEEKEND. && .NEAR TERM /TODAY/... ISSUED AT 353 AM EDT MON APR 1 2013 FORECAST FOCUS IS ON NEED FOR ANY POPS FROM EARLY TO MID MORNING. UPPER WAVE IS CURRENTLY MOVING SOUTHEAST THROUGH SOUTHERN IOWA AND WESTERN ILLINOIS. RADAR MOSAIC SHOWS WEAK ECHOES OVER WESTERN AND CENTRAL ILLINOIS AS WELL AS SOME ENTERING WESTERN INDIANA BUT SURFACE OBS SHOW NO PRECIP AT THE GROUND. GFS AND NAM ARE BOTH DRY AND GUIDANCE IS AS WELL. RAPID REFRESH AND RAP SHOW SOME DEVELOPMENT OCCURRING ACROSS THE SOUTHERN COUNTIES AROUND 11-12Z AND MOVING THROUGH BY 15Z. WITH BOTH OF THE RAPID UPDATE MODELS SHOWING THIS DEVELOPMENT WILL GO AHEAD AND LEAVE A SLIGHT CHANCE FOR RAIN AND SNOW MOVING ACROSS THE SOUTH FROM 11 TO 15Z AND DRY FROM 15Z ON. SHOULD NOT AMOUNT TO ANYTHING. WILL DROP ANY MENTION OF FLURRIES ELSEWHERE. CLOUDS SHOULD SCATTER OUT AS THE DAY GOES ON. WILL SEE COLD ADVECTION THROUGHOUT THE DAY SO TEMPERATURES SHOULD STRUGGLE TO WARM AND THUS WENT WITH A CONSENSUS OF RAW MODEL NUMBERS SINCE CLIMATOLOGY COULD BIAS THINGS UP. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 353 AM EDT MON APR 1 2013 HIGH PRESSURE WILL DOMINATE THE WEATHER IN THE SHORT TERM. MODELS ARE IN GOOD AGREEMENT AND WILL USE A CONSENSUS. WITH MOSTLY CLEAR TO CLEAR SKIES THROUGHOUT THE SHORT TERM STUCK CLOSE TO COOLER GUIDANCE NUMBERS AT NIGHT OF LOW TO MIDDLE 20S. FOR HIGHS TUESDAY AGAIN THOUGHT GUIDANCE WAS BIASED A BIT WARM FROM CLIMATOLOGY SO STUCK WITH A RAW MODEL CONSENSUS IN THE LOW TO MID 40S...BUT BY WEDNESDAY THE AIR MASS SHOULD BE REBOUNDING UNDER WARM ADVECTION AND A COMPLETE CONSENSUS LOOKED GOOD IN THE UPPER 40S TO LOW 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 324 AM EDT MON APR 1 2013 A LARGE AREA OF HIGH PRESSURE WILL BE MOVING AWAY TO THE EAST ON THURSDAY WITH A SPLIT FLOW PATTERN ALOFT AS A WEAK FRONT APPROACHES FROM THE NORTHWEST AND AN UPPER LOW TRACKS ACROSS THE SOUTHERN PLAINS. MODEL CONSENSUS HAS BEEN TRACKING THE UPPER WAVE FURTHER NORTH OVER THE LAST COUPLE DAYS AND BRINGS THE NORTHERN FRINGES OF THE RAINFALL ASSOCIATED WITH THE UPPER LOW INTO THE OHIO RIVER VALLEY THURSDAY NIGHT. CONSIDERING THE NORTHERLY LOW LEVEL FLOW...PRESENCE OF DRIER AIR OVER THE REGION AND THE BULK OF THE DEEPER FORCING REMAINING TO THE SOUTH OF THE FORECAST AREA...WILL CONTINUE TO KEEP A DRY FORECAST GOING THURSDAY NIGHT. DO ANTICIPATE AN INCREASE IN CLOUDS OVER THE SOUTHERN COUNTIES THURSDAY NIGHT AND EARLY FRIDAY AS THE UPPER WAVE PASSES TO THE SOUTH. THE AFOREMENTIONED WEAK FRONT APPROACHING FROM THE NORTHWEST SET TO WASH OUT ACROSS THE LOWER GREAT LAKES THURSDAY NIGHT. AS THE UPPER WAVE WEAKENS AND SHIFTS INTO THE SOUTHEAST STATES BY FRIDAY AFTERNOON...HIGH PRESSURE WILL REESTABLISH ACROSS THE OHIO VALLEY WITH AN EXPANSION OF RIDGING ALOFT BRINGING WARMER AIR INTO THE REGION. LOW LEVEL THERMALS SUPPORT HIGH TEMPS RISING INTO THE 60S BY SATURDAY. FORECAST MORE MUDDLED FOR THE SECOND HALF OF THE WEEKEND AS A DEVELOPING WARM FRONT SETS UP OVER THE LOWER GREAT LAKES AND A SURFACE WAVE TRACKS ALONG THE BOUNDARY ON SUNDAY. WILL CARRY LOW CHANCE POPS SATURDAY NIGHT INTO SUNDAY AS THE SURFACE WAVE PASSES THROUGH THE AREA. APPEARS THE BOUNDARY MAY SETTLE FURTHER SOUTH NEAR THE OHIO RIVER BY LATE SUNDAY WITH THE PASSAGE OF THE LOW...BEFORE THE BOUNDARY RETURNS BACK NORTH EARLY NEXT WEEK. LOW LEVEL THERMALS STILL SUGGESTIVE OF HIGHS IN THE 60S FOR SUNDAY EVEN AS THE BOUNDARY SHIFTS SOUTH...WITH POSSIBILITY FOR WARMER DAYTIME HIGHS EARLY NEXT WEEK ONCE THE FRONT LIFTS BACK NORTH. && .AVIATION /DISCUSSION FOR THE 01/06Z TAFS/... ISSUED AT 104 AM EDT MON APR 1 2013 VFR THROUGH THE PERIOD. SCT TO BKN MID CLOUD LIKELY THE ONLY SKY COVER THROUGH THE NIGHT. WINDS WILL ONCE AGAIN GUST TOMORROW TO NEAR 20KT...AND DIURNAL CUMULUS WILL FORM AROUND 5KFT. NO VISIBILITY ISSUES ANTICIPATED THROUGH THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS WICHITA KS
1230 PM CDT MON APR 1 2013 .UPDATE... ISSUED AT 1229 PM CDT MON APR 1 2013 PUT OUT ANOTHER UPDATE TO ADD LIGHT SNOW AS A PRECIP TYPE BASED ON LATEST REPORTS. HOWEVER THE BIGGER REASON FOR THE UPDATE WAS TO DROP HIGHS TODAY SEVERAL DEGREES. ISENTROPIC LIFT NORTH OF THE SURFACE COLD FRONT HAS RESULTED IN NUMEROUS RAIN/SNOW SHOWERS ACROSS MOST OF SOUTH CENTRAL KS. THIS ACTIVITY SHOULD CONTINUE TRACKING OFF TO THE EAST-SOUTHEAST THIS AFTERNOON. WITH WARM GROUND TEMPS...NO ACCUMULATION IS EXPECTED. THE INCREASED CLOUD COVER WILL COMBINE WITH TEMPS WET-BULBING DOWN TO KEEP TEMPS FROM CLIMBING MUCH THIS AFTERNOON. SO WENT AHEAD AND DROPPED HIGHS SEVERAL DEGREES. UPDATE ISSUED AT 1013 AM CDT MON APR 1 2013 SENT OUT A QUICK UPDATE TO KEEP UP WITH CURRENT PRECIP TRENDS. ISENTROPIC LIFT ALONG THE 305K SURFACE HAS RESULTED IN PRECIP EXPANDING OVER SW PORTIONS OF THE FORECAST AREA. THIS ACTIVITY SHOULD CONTINUE TO PUSH EAST LATE THIS MORNING INTO THE EARLY AFTERNOON HOURS. A COUPLE RUMBLES OF THUNDER MAY MIX WITH THE SHOWERS. LAWSON && .SYNOPSIS... ISSUED AT 332 AM CDT MON APR 1 2013 A POTENT DISTURBANCE IS PLUNGING SOUTHWARD INTO THE GREAT LAKES REGION...CAUSING A COLD FRONT TO DIVE SOUTHWARD ACROSS THE CENTRAL PLAINS. THE COLD FRONT HAS MADE IT HALF WAY THROUGH KANSAS AS OF THIS ISSUANCE AND WILL CONTINUE TO MOVE SOUTHWARD THROUGH OKLAHOMA DURING THE DAY. WINDS ARE GUSTY BEHIND THE FRONT WITH LOW TO MID LEVEL CLOUDS. LOOKING WEST...ANOTHER DISTURBANCE IS LOCATED OVER MID-CALIFORNIA/NEVADA/UTAH. THIS WILL BE THE WEATHER MAKER FOR THE FIRST PART OF THE WEEK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 332 AM CDT MON APR 1 2013 THIS PERIOD WILL BE RAINY OFF AND ON AND COOLER FOR MUCH OF SOUTHERN KANSAS. THE LATEST GUIDANCE...NAM/GFS/ECMWF AND HRRR INDICATE PRECIPITATION DEVELOPING ACROSS SOUTH CENTRAL KANSAS AROUND MID AFTERNOON TODAY BEFORE SPREADING EAST ACROSS SOUTHERN KANSAS THROUGH THE DAY AND OVERNIGHT. PRECIPITATION WILL DEVELOP NEAR THE 850MB FRONT. THE UPPER LEVEL WAVE OVER THE WEST WILL CONTINUE TO MOVE TOWARDS THE AREA...ENHANCING UPPER LEVEL SUPPORT. THE 850MB FRONT WILL REMAIN STATIONARY...KEEPING THE PRECIPITATION CHANCES THROUGH WEDNESDAY. NOT EXPECTING THUNDER WITH THIS EVENT WITH VERY LOW MUCAPE VALUES...BUT CANNOT RULE OUT AN ISOLATED LIGHTNING STRIKE. THIS PERIOD WILL REMAIN COOLER...AS THE COLD FRONT USHERED IN UNSEASONABLY COOL AIR. WITH COLD AIR ADVECTION...CLOUDY SKIES AND RAIN...TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. TUESDAY LOOKS TO BE THE COOLEST DAY WITH CLOUD COVER AND RAIN. BILLINGS .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON APR 1 2013 BY THURSDAY THE UPPER LEVEL DISTURBANCE THAT WILL IMPACT THE AREA FOR THE FIRST HALF OF THE FORECAST WILL FINALLY BE ON ITS WAY EAST. SURFACE HIGH PRESSURE WILL MOVE OVERHEAD THURSDAY WITH CLEARING SKIES IN THE SUBSIDENCE ZONE OF THE UPPER WAVE. THIS WILL ALLOW TEMPERATURES TO WARM BACK INTO THE UPPER 50S AND LOW 60S. TEMPERATURES WILL CONTINUE TO INCREASE FOR FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. LEE CYCLOGENESIS WILL DEEPEN AHEAD OF THE NEXT WAVE...WITH STRONG WARM AIR ADVECTION AND MIXING...TEMPS WILL REACH BACK INTO THE 60S AND 70S. THE NEXT DISTURBANCE WILL MOVE ACROSS THE NORTHERN PLAINS...DRAGGING A COLD FRONT ACROSS THE REGION. THE MAIN LIFT ASSOCIATED WITH THIS FRONT WILL BE ACROSS THE NORTHERN PLAINS...SO NOT EXPECTING MUCH IN THE WAY OF PRECIPITATION ALONG THE FRONTAL BOUNDARY AND HAVE LEFT THE FORECAST DRY FOR SATURDAY AND SUNDAY. TEMPERATURES BEHIND THE FRONT WILL ONLY DECREASE SLIGHTLY. ANOTHER WAVE WILL APPROACH FOR THE VERY END OF THE FORECAST AND PRECIPITATION MAY RETURN FOR SUNDAY AND INTO THE EARLY PART OF NEXT WEEK. WILL CONTINUE TO WATCH THIS PERIOD AS THE FORECAST EVOLVES AS THE TIME PERIOD NEARS. BILLINGS && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1229 PM CDT MON APR 1 2013 MAIN AVIATION FORECAST CONCERNS WILL PRECIP THIS AFTERNOON ALONG WITH LOWERING CIGS TONIGHT. THE PRECIP AFFECTING SOUTH CENTRAL KS WILL CONTINUE SLOWLY TRACKING OFF TO THE SOUTHEAST THIS AFTERNOON WITH MAINLY KICT BEING AFFECTED. A RAIN-SNOW MIX WILL BE THE MAIN PRECIP TYPE. THERE SHOULD BE A BREAK IN THE PRECIP LATE THIS AFTERNOON/EARLY THIS EVENING BEFORE ISENTROPIC LIFT GETS CRANKED UP AGAIN AFTER DARK. HOWEVER FOR THIS EVENING FEEL THAT THE BULK OF THE PRECIP WILL BE SOUTH OF THE KS-OK BORDER WITH KICT BEING ON THE NORTHERN FRINGES OF THE PRECIP. IN ADDITION...CIGS WILL START TO LOWER TOWARD SUNRISE ACROSS SOUTH CENTRAL KS WITH KICT POSSIBLY GETTING INTO SOME MVFR CONDITIONS BY 12Z. LAWSON && .FIRE WEATHER... ISSUED AT 332 AM CDT MON APR 1 2013 VERY LITTLE IN THE WAY OF FIRE CONCERN FOR MUCH OF THE FORECAST. LIGHT WINDS AND PRECIPITATION WILL KEEP GRASSLAND FIRE DANGER LOW. WITH STRONGER WINDS AND WARMER TEMPERATURES ON FRIDAY...GRASSLAND FIRE DANGER WILL BE VERY HIGH. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 45 35 43 35 / 80 60 50 30 HUTCHINSON 42 33 45 32 / 50 40 40 20 NEWTON 43 32 43 31 / 50 30 30 20 ELDORADO 45 33 44 33 / 80 40 40 20 WINFIELD-KWLD 49 36 42 36 / 90 70 70 40 RUSSELL 43 30 48 30 / 10 30 20 10 GREAT BEND 42 31 46 31 / 20 30 30 20 SALINA 43 31 50 33 / 10 20 10 10 MCPHERSON 42 32 46 32 / 20 30 20 10 COFFEYVILLE 52 37 44 36 / 70 60 70 40 CHANUTE 48 34 44 34 / 40 30 30 10 IOLA 47 33 45 33 / 20 20 20 10 PARSONS-KPPF 50 35 44 35 / 60 50 50 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1013 AM CDT MON APR 1 2013 .UPDATE... ISSUED AT 1013 AM CDT MON APR 1 2013 SENT OUT A QUICK UPDATE TO KEEP UP WITH CURRENT PRECIP TRENDS. ISENTROPIC LIFT ALONG THE 305K SURFACE HAS RESULTED IN PRECIP EXPANDING OVER SW PORTIONS OF THE FORECAST AREA. THIS ACTIVITY SHOULD CONTINUE TO PUSH EAST LATE THIS MORNING INTO THE EARLY AFTERNOON HOURS. A COUPLE RUMBLES OF THUNDER MAY MIX WITH THE SHOWERS. LAWSON && .SYNOPSIS... ISSUED AT 332 AM CDT MON APR 1 2013 A POTENT DISTURBANCE IS PLUNGING SOUTHWARD INTO THE GREAT LAKES REGION...CAUSING A COLD FRONT TO DIVE SOUTHWARD ACROSS THE CENTRAL PLAINS. THE COLD FRONT HAS MADE IT HALF WAY THROUGH KANSAS AS OF THIS ISSUANCE AND WILL CONTINUE TO MOVE SOUTHWARD THROUGH OKLAHOMA DURING THE DAY. WINDS ARE GUSTY BEHIND THE FRONT WITH LOW TO MID LEVEL CLOUDS. LOOKING WEST...ANOTHER DISTURBANCE IS LOCATED OVER MID-CALIFORNIA/NEVADA/UTAH. THIS WILL BE THE WEATHER MAKER FOR THE FIRST PART OF THE WEEK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 332 AM CDT MON APR 1 2013 THIS PERIOD WILL BE RAINY OFF AND ON AND COOLER FOR MUCH OF SOUTHERN KANSAS. THE LATEST GUIDANCE...NAM/GFS/ECMWF AND HRRR INDICATE PRECIPITATION DEVELOPING ACROSS SOUTH CENTRAL KANSAS AROUND MID AFTERNOON TODAY BEFORE SPREADING EAST ACROSS SOUTHERN KANSAS THROUGH THE DAY AND OVERNIGHT. PRECIPITATION WILL DEVELOP NEAR THE 850MB FRONT. THE UPPER LEVEL WAVE OVER THE WEST WILL CONTINUE TO MOVE TOWARDS THE AREA...ENHANCING UPPER LEVEL SUPPORT. THE 850MB FRONT WILL REMAIN STATIONARY...KEEPING THE PRECIPITATION CHANCES THROUGH WEDNESDAY. NOT EXPECTING THUNDER WITH THIS EVENT WITH VERY LOW MUCAPE VALUES...BUT CANNOT RULE OUT AN ISOLATED LIGHTNING STRIKE. THIS PERIOD WILL REMAIN COOLER...AS THE COLD FRONT USHERED IN UNSEASONABLY COOL AIR. WITH COLD AIR ADVECTION...CLOUDY SKIES AND RAIN...TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. TUESDAY LOOKS TO BE THE COOLEST DAY WITH CLOUD COVER AND RAIN. BILLINGS .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON APR 1 2013 BY THURSDAY THE UPPER LEVEL DISTURBANCE THAT WILL IMPACT THE AREA FOR THE FIRST HALF OF THE FORECAST WILL FINALLY BE ON ITS WAY EAST. SURFACE HIGH PRESSURE WILL MOVE OVERHEAD THURSDAY WITH CLEARING SKIES IN THE SUBSIDENCE ZONE OF THE UPPER WAVE. THIS WILL ALLOW TEMPERATURES TO WARM BACK INTO THE UPPER 50S AND LOW 60S. TEMPERATURES WILL CONTINUE TO INCREASE FOR FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. LEE CYCLOGENESIS WILL DEEPEN AHEAD OF THE NEXT WAVE...WITH STRONG WARM AIR ADVECTION AND MIXING...TEMPS WILL REACH BACK INTO THE 60S AND 70S. THE NEXT DISTURBANCE WILL MOVE ACROSS THE NORTHERN PLAINS...DRAGGING A COLD FRONT ACROSS THE REGION. THE MAIN LIFT ASSOCIATED WITH THIS FRONT WILL BE ACROSS THE NORTHERN PLAINS...SO NOT EXPECTING MUCH IN THE WAY OF PRECIPITATION ALONG THE FRONTAL BOUNDARY AND HAVE LEFT THE FORECAST DRY FOR SATURDAY AND SUNDAY. TEMPERATURES BEHIND THE FRONT WILL ONLY DECREASE SLIGHTLY. ANOTHER WAVE WILL APPROACH FOR THE VERY END OF THE FORECAST AND PRECIPITATION MAY RETURN FOR SUNDAY AND INTO THE EARLY PART OF NEXT WEEK. WILL CONTINUE TO WATCH THIS PERIOD AS THE FORECAST EVOLVES AS THE TIME PERIOD NEARS. BILLINGS && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 648 AM CDT MON APR 1 2013 A SHARP COLD FRONT HAS ALREADY MOVED ACROSS MOST LOCATIONS THIS MORNING EXPECT SOME GUSTY WINDS TO 25 KTS FOR A FEW HOURS AFTER THE FRONT MOVES THROUGH. WILL ALSO SEE SOME POST FRONTAL MVFR CEILINGS ALSO DROP SOUTH ACROSS THE REGION FOR A FEW HOURS AFTER THE FRONT PASSES...WITH CEILINGS OF 1500 FT AGL. EXPECT THIS MVFR CLOUD DECK TO BE SHORT LIVED....WITH LOWER CLOUDS STAYING AROUND FOR ONLY 4 OR 5 HOURS. LIFT OVER THE TOP OF THE SHALLOW COLD AIR ACROSS SRN KS...WILL LEAD TO A CHANCE OF SOME LIGHT RAIN SHOWERS FOR MAINLY SRN KS. SO WILL INCLUDE A VCSH FOR THE KICT/KHUT AND KCNU TAF SITES AFTER 22Z/MON. WILL SEE MORE OF WIDESPREAD LIGHT RAIN CHANCE DEVELOP LATE TNGT INTO TUE AM...AFTER 12Z TUE. COULD ALSO SEE CEILINGS DROP TO LOW MVFR OR POSSIBLY IFR ACROSS SRN KS ON TUE....BUT THIS IS BEYOND THIS TAF TIME FRAME. KETCHAM && .FIRE WEATHER... ISSUED AT 332 AM CDT MON APR 1 2013 VERY LITTLE IN THE WAY OF FIRE CONCERN FOR MUCH OF THE FORECAST. LIGHT WINDS AND PRECIPITATION WILL KEEP GRASSLAND FIRE DANGER LOW. WITH STRONGER WINDS AND WARMER TEMPERATURES ON FRIDAY...GRASSLAND FIRE DANGER WILL BE VERY HIGH. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 51 35 43 35 / 40 60 50 30 HUTCHINSON 50 33 45 32 / 30 40 40 20 NEWTON 51 32 43 31 / 20 30 30 20 ELDORADO 51 33 44 33 / 30 40 40 20 WINFIELD-KWLD 53 36 42 36 / 40 70 70 40 RUSSELL 51 30 48 30 / 10 30 20 10 GREAT BEND 50 31 46 31 / 20 30 30 20 SALINA 52 31 50 33 / 10 20 10 10 MCPHERSON 51 32 46 32 / 20 30 20 10 COFFEYVILLE 55 37 44 36 / 30 60 70 40 CHANUTE 53 34 44 34 / 20 30 30 10 IOLA 52 33 45 33 / 20 20 20 10 PARSONS-KPPF 53 35 44 35 / 30 50 50 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
651 AM CDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 332 AM CDT MON APR 1 2013 A POTENT DISTURBANCE IS PLUNGING SOUTHWARD INTO THE GREAT LAKES REGION...CAUSING A COLD FRONT TO DIVE SOUTHWARD ACROSS THE CENTRAL PLAINS. THE COLD FRONT HAS MADE IT HALF WAY THROUGH KANSAS AS OF THIS ISSUANCE AND WILL CONTINUE TO MOVE SOUTHWARD THROUGH OKLAHOMA DURING THE DAY. WINDS ARE GUSTY BEHIND THE FRONT WITH LOW TO MID LEVEL CLOUDS. LOOKING WEST...ANOTHER DISTURBANCE IS LOCATED OVER MID-CALIFORNIA/NEVADA/UTAH. THIS WILL BE THE WEATHER MAKER FOR THE FIRST PART OF THE WEEK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 332 AM CDT MON APR 1 2013 THIS PERIOD WILL BE RAINY OFF AND ON AND COOLER FOR MUCH OF SOUTHERN KANSAS. THE LATEST GUIDANCE...NAM/GFS/ECMWF AND HRRR INDICATE PRECIPITATION DEVELOPING ACROSS SOUTH CENTRAL KANSAS AROUND MID AFTERNOON TODAY BEFORE SPREADING EAST ACROSS SOUTHERN KANSAS THROUGH THE DAY AND OVERNIGHT. PRECIPITATION WILL DEVELOP NEAR THE 850MB FRONT. THE UPPER LEVEL WAVE OVER THE WEST WILL CONTINUE TO MOVE TOWARDS THE AREA...ENHANCING UPPER LEVEL SUPPORT. THE 850MB FRONT WILL REMAIN STATIONARY...KEEPING THE PRECIPITATION CHANCES THROUGH WEDNESDAY. NOT EXPECTING THUNDER WITH THIS EVENT WITH VERY LOW MUCAPE VALUES...BUT CANNOT RULE OUT AN ISOLATED LIGHTNING STRIKE. THIS PERIOD WILL REMAIN COOLER...AS THE COLD FRONT USHERED IN UNSEASONABLY COOL AIR. WITH COLD AIR ADVECTION...CLOUDY SKIES AND RAIN...TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. TUESDAY LOOKS TO BE THE COOLEST DAY WITH CLOUD COVER AND RAIN. BILLINGS .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON APR 1 2013 BY THURSDAY THE UPPER LEVEL DISTURBANCE THAT WILL IMPACT THE AREA FOR THE FIRST HALF OF THE FORECAST WILL FINALLY BE ON ITS WAY EAST. SURFACE HIGH PRESSURE WILL MOVE OVERHEAD THURSDAY WITH CLEARING SKIES IN THE SUBSIDENCE ZONE OF THE UPPER WAVE. THIS WILL ALLOW TEMPERATURES TO WARM BACK INTO THE UPPER 50S AND LOW 60S. TEMPERATURES WILL CONTINUE TO INCREASE FOR FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. LEE CYCLOGENESIS WILL DEEPEN AHEAD OF THE NEXT WAVE...WITH STRONG WARM AIR ADVECTION AND MIXING...TEMPS WILL REACH BACK INTO THE 60S AND 70S. THE NEXT DISTURBANCE WILL MOVE ACROSS THE NORTHERN PLAINS...DRAGGING A COLD FRONT ACROSS THE REGION. THE MAIN LIFT ASSOCIATED WITH THIS FRONT WILL BE ACROSS THE NORTHERN PLAINS...SO NOT EXPECTING MUCH IN THE WAY OF PRECIPITATION ALONG THE FRONTAL BOUNDARY AND HAVE LEFT THE FORECAST DRY FOR SATURDAY AND SUNDAY. TEMPERATURES BEHIND THE FRONT WILL ONLY DECREASE SLIGHTLY. ANOTHER WAVE WILL APPROACH FOR THE VERY END OF THE FORECAST AND PRECIPITATION MAY RETURN FOR SUNDAY AND INTO THE EARLY PART OF NEXT WEEK. WILL CONTINUE TO WATCH THIS PERIOD AS THE FORECAST EVOLVES AS THE TIME PERIOD NEARS. BILLINGS && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 648 AM CDT MON APR 1 2013 A SHARP COLD FRONT HAS ALREADY MOVED ACROSS MOST LOCATIONS THIS MORNING EXPECT SOME GUSTY WINDS TO 25 KTS FOR A FEW HOURS AFTER THE FRONT MOVES THROUGH. WILL ALSO SEE SOME POST FRONTAL MVFR CEILINGS ALSO DROP SOUTH ACROSS THE REGION FOR A FEW HOURS AFTER THE FRONT PASSES...WITH CEILINGS OF 1500 FT AGL. EXPECT THIS MVFR CLOUD DECK TO BE SHORT LIVED....WITH LOWER CLOUDS STAYING AROUND FOR ONLY 4 OR 5 HOURS. LIFT OVER THE TOP OF THE SHALLOW COLD AIR ACROSS SRN KS...WILL LEAD TO A CHANCE OF SOME LIGHT RAIN SHOWERS FOR MAINLY SRN KS. SO WILL INCLUDE A VCSH FOR THE KICT/KHUT AND KCNU TAF SITES AFTER 22Z/MON. WILL SEE MORE OF WIDESPREAD LIGHT RAIN CHANCE DEVELOP LATE TNGT INTO TUE AM...AFTER 12Z TUE. COULD ALSO SEE CEILINGS DROP TO LOW MVFR OR POSSIBLY IFR ACROSS SRN KS ON TUE....BUT THIS IS BEYOND THIS TAF TIME FRAME. KETCHAM && .FIRE WEATHER... ISSUED AT 332 AM CDT MON APR 1 2013 VERY LITTLE IN THE WAY OF FIRE CONCERN FOR MUCH OF THE FORECAST. LIGHT WINDS AND PRECIPITATION WILL KEEP GRASSLAND FIRE DANGER LOW. WITH STRONGER WINDS AND WARMER TEMPERATURES ON FRIDAY...GRASSLAND FIRE DANGER WILL BE VERY HIGH. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 51 35 43 35 / 40 60 50 30 HUTCHINSON 50 33 45 32 / 30 40 40 20 NEWTON 51 32 43 31 / 30 30 30 20 ELDORADO 51 33 44 33 / 30 40 40 20 WINFIELD-KWLD 53 36 42 36 / 40 70 70 40 RUSSELL 51 30 48 30 / 20 30 20 10 GREAT BEND 50 31 46 31 / 20 30 30 20 SALINA 52 31 50 33 / 20 20 10 10 MCPHERSON 51 32 46 32 / 30 30 20 10 COFFEYVILLE 55 37 44 36 / 40 60 70 40 CHANUTE 53 34 44 34 / 30 30 30 10 IOLA 52 33 45 33 / 30 20 20 10 PARSONS-KPPF 53 35 44 35 / 30 50 50 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
335 AM CDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 332 AM CDT MON APR 1 2013 A POTENT DISTURBANCE IS PLUNGING SOUTHWARD INTO THE GREAT LAKES REGION...CAUSING A COLD FRONT TO DIVE SOUTHWARD ACROSS THE CENTRAL PLAINS. THE COLD FRONT HAS MADE IT HALF WAY THROUGH KANSAS AS OF THIS ISSUANCE AND WILL CONTINUE TO MOVE SOUTHWARD THROUGH OKLAHOMA DURING THE DAY. WINDS ARE GUSTY BEHIND THE FRONT WITH LOW TO MID LEVEL CLOUDS. LOOKING WEST...ANOTHER DISTURBANCE IS LOCATED OVER MID-CALIFORNIA/NEVADA/UTAH. THIS WILL BE THE WEATHER MAKER FOR THE FIRST PART OF THE WEEK. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 332 AM CDT MON APR 1 2013 THIS PERIOD WILL BE RAINY OFF AND ON AND COOLER FOR MUCH OF SOUTHERN KANSAS. THE LATEST GUIDANCE...NAM/GFS/ECMWF AND HRRR INDICATE PRECIPITATION DEVELOPING ACROSS SOUTH CENTRAL KANSAS AROUND MID AFTERNOON TODAY BEFORE SPREADING EAST ACROSS SOUTHERN KANSAS THROUGH THE DAY AND OVERNIGHT. PRECIPITATION WILL DEVELOP NEAR THE 850MB FRONT. THE UPPER LEVEL WAVE OVER THE WEST WILL CONTINUE TO MOVE TOWARDS THE AREA...ENHANCING UPPER LEVEL SUPPORT. THE 850MB FRONT WILL REMAIN STATIONARY...KEEPING THE PRECIPITATION CHANCES THROUGH WEDNESDAY. NOT EXPECTING THUNDER WITH THIS EVENT WITH VERY LOW MUCAPE VALUES...BUT CANNOT RULE OUT AN ISOLATED LIGHTNING STRIKE. THIS PERIOD WILL REMAIN COOLER...AS THE COLD FRONT USHERED IN UNSEASONABLY COOL AIR. WITH COLD AIR ADVECTION...CLOUDY SKIES AND RAIN...TEMPERATURES WILL BE 10 TO 20 DEGREES BELOW NORMAL. TUESDAY LOOKS TO BE THE COOLEST DAY WITH CLOUD COVER AND RAIN. BILLINGS .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON APR 1 2013 BY THURSDAY THE UPPER LEVEL DISTURBANCE THAT WILL IMPACT THE AREA FOR THE FIRST HALF OF THE FORECAST WILL FINALLY BE ON ITS WAY EAST. SURFACE HIGH PRESSURE WILL MOVE OVERHEAD THURSDAY WITH CLEARING SKIES IN THE SUBSIDENCE ZONE OF THE UPPER WAVE. THIS WILL ALLOW TEMPERATURES TO WARM BACK INTO THE UPPER 50S AND LOW 60S. TEMPERATURES WILL CONTINUE TO INCREASE FOR FRIDAY AND SATURDAY AHEAD OF THE NEXT SYSTEM. LEE CYCLOGENESIS WILL DEEPEN AHEAD OF THE NEXT WAVE...WITH STRONG WARM AIR ADVECTION AND MIXING...TEMPS WILL REACH BACK INTO THE 60S AND 70S. THE NEXT DISTURBANCE WILL MOVE ACROSS THE NORTHERN PLAINS...DRAGGING A COLD FRONT ACROSS THE REGION. THE MAIN LIFT ASSOCIATED WITH THIS FRONT WILL BE ACROSS THE NORTHERN PLAINS...SO NOT EXPECTING MUCH IN THE WAY OF PRECIPITATION ALONG THE FRONTAL BOUNDARY AND HAVE LEFT THE FORECAST DRY FOR SATURDAY AND SUNDAY. TEMPERATURES BEHIND THE FRONT WILL ONLY DECREASE SLIGHTLY. ANOTHER WAVE WILL APPROACH FOR THE VERY END OF THE FORECAST AND PRECIPITATION MAY RETURN FOR SUNDAY AND INTO THE EARLY PART OF NEXT WEEK. WILL CONTINUE TO WATCH THIS PERIOD AS THE FORECAST EVOLVES AS THE TIME PERIOD NEARS. BILLINGS && .AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU ISSUED AT 1208 AM CDT MON APR 1 2013 AT 05Z A STRONG ALMOST E-W ORIENTED COLD FRONT THAT HAS BEEN MOVING S THIS EVENING ENTERED NRN KS ~03Z & SHOULD STILL ARRIVE KRSL & KSLN 08Z. THE COLD FRONT SHOULD REACH SC & SE KS ~10Z. DURING FRONTAL PASSAGE WINDS THAT ARE VARIABLE <7KTS WILL QUICKLY & ABRUPTLY SHIFT TOWARD THE NE & INCREASE TO A SUSTAINED ~17KTS/20MPH WITH GUSTS ~25KTS. POST-COLD FRONTAL ~1,500FT STRATOCU WILL SPREAD OVER PRIMARILY KSLN ~11Z BUT ONLY LAST TIL ~15Z. NE WINDS WILL GRADUALLY DIMINISH IN A N-S MANNER AS HIGH PRESSURE SPREADS S/SE FROM THE DAKOTAS TO NEBRASKA. ES && .FIRE WEATHER... ISSUED AT 332 AM CDT MON APR 1 2013 VERY LITTLE IN THE WAY OF FIRE CONCERN FOR MUCH OF THE FORECAST. LIGHT WINDS AND PRECIPITATION WILL KEEP GRASSLAND FIRE DANGER LOW. WITH STRONGER WINDS AND WARMER TEMPERATURES ON FRIDAY...GRASSLAND FIRE DANGER WILL BE VERY HIGH. BILLINGS && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 51 35 43 35 / 40 60 50 30 HUTCHINSON 50 33 45 32 / 30 40 40 20 NEWTON 51 32 43 31 / 30 30 30 20 ELDORADO 51 33 44 33 / 30 40 40 20 WINFIELD-KWLD 53 36 42 36 / 40 70 70 40 RUSSELL 51 30 48 30 / 20 30 20 10 GREAT BEND 50 31 46 31 / 20 30 30 20 SALINA 52 31 50 33 / 20 20 10 10 MCPHERSON 51 32 46 32 / 30 30 20 10 COFFEYVILLE 55 37 44 36 / 40 60 70 40 CHANUTE 53 34 44 34 / 30 30 30 10 IOLA 52 33 45 33 / 30 20 20 10 PARSONS-KPPF 53 35 44 35 / 30 50 50 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
927 AM EDT MON APR 1 2013 .SYNOPSIS... NORTHWEST WINDS WILL PROVIDE BELOW NORMAL TEMPERATURES THROUGH MIDWEEK. AN UPPER LEVEL SYSTEM WILL BRING THE RISK FOR RAIN OR SNOW SHOWERS TODAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A MIX OF RAIN AND SNOW SHOWERS CONTINUE TO CROSS THE REGION ALONG AND BEHIND THE COLD FRONT THIS MORNING. HAVE BUMPED UP THE POPS ACCORDINGLY USING RUC DATA THAT SEEMS TO BE HANDLING THE TIMING AND SCATTERED NATURE OF THE SHOWERS QUITE WELL. TEMPERATURES AHEAD OF THIS BOUNDARY HAVE WARMED UP SLIGHTLY BUT THIS WILL BE BRIEF AS COLD ADVECTION SHOULD GENERALLY KEEP A DOWNWARD TREND IN TEMPS DURING THE DAY. LATEST MODEL SOUNDINGS ARE SHOWING A DRY AIR MASS SETTLING IN THE LOWER LEVELS THIS AFTERNOON. THIS WILL LIMIT LAKE EFFECT /UP-SLOPE SNOW SHOWER DEVELOPMENT. THE HIGHEST RIDGES WILL HAVE THE BEST CHANCE TO SEE MORE NUMEROUS SNOW SHOWERS AS ELEVATION WILL KEEP THEM IN A THE SATURATED LAYER. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... OUR BRIEF ACQUAINTANCE WITH SPRING WILL SADLY DEPART AS WE ONCE AGAIN RETURN TO A PATTERN MORE REMINISCENT OF WINTER WITH THE EASTERN HALF OF THE CONUS UNDER THE INFLUENCE OF A LARGE UPPER LEVEL TROUGH THROUGH MUCH OF THE PERIOD. WHILE THE UPPER LEVEL FLOW MAY KEEP A SLIGHTLY MORE WESTERLY THAN NORTHWESTERLY COMPONENT...SHORTWAVES DIVING THROUGH THE COLD UPPER LEVEL FLOW SHOULD PROVIDE AT LEAST CLOUD COVER THROUGH LATE TUESDAY AND SOME LAKE ENHANCED SNOW SHOWERS POSSIBLE IMMEDIATELY DOWNWIND OF LAKE ERIE...THOUGH IT IS QUESTIONABLE TO WHETHER IT WILL REALLY IMPACT OUR NORTHERN ZONES VERY MUCH. BY WEDNESDAY...MODELS SHOW A FEW INCONSISTENCIES IN THE PLACEMENT AND STRENGTH OF A SHORTWAVE DIVING THROUGH THE TROUGH AND ITS IMPACT TO THE REGION. AS SUCH...OPTED TO REMAIN CLOSER TO THE ENSEMBLE MEANS WHICH KEEP THE REGION DRY. EVEN FOR THE START OF APRIL....COLD ADVECTION AND CLOUD COVER SHOULD KEEP TEMPERATURES BELOW SEASONAL AVERAGES THROUGH THE PERIOD. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... MODEL AND ENSEMBLE SOLUTIONS ALL FAVOR A DRY EXTENDED FORECAST WITH LOW PRES SUPPRESSED TO OUR SOUTH IN THE SPLIT FLOW PATTERN LATE IN THE WEEK. HOWEVER...AS THE PRECIP SHIELD OF THAT SYSTEM MAY CLIP THE SOUTHEASTERN PORTIONS OF THE FORECAST AREA...HAVE INCLUDED SLGT TO CHC POPS FOR FRIDAY INTO FRIDAY NIGHT. HIGH PRESSURE IS CURRENTLY TIMED TO BRING DRY WEATHER FOR SATURDAY....BUT ANOTHER FRONT MAY BRING A CHANCE OF SHOWERS FOR SUNDAY.. TEMPERATURES THROUGH THE EXTENDED MODERATE TOWARD AVERAGE. WITH A SPLIT FLOW LIKELY TO BE IN PLACE...OUR AREA SHOULD REMAIN LARGELY LOCKED BETWEEN THE NORTHERN AND SOUTHERN STREAM. AS A RESULT...NO WILD SWINGS OF TEMPS ARE ANTICIPATED. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... A RELATIVELY DRY COLD FRONT WILL CROSS THE TERMINALS THIS MORNING...BRINGING A WIND SHIFT FROM SOUTHWESTERLY TO NORTHWESTERLY WITH ITS PASSAGE. THE FRONT WILL CROSS THE TERMINALS BETWEEN 09Z AND 13Z. WINDS BEHIND THE FRONT WILL INCREASE TO AROUND 15KTS WITH GUSTS UP TO 25KTS LATE THIS MORNING INTO THE AFTERNOON. WITH LITTLE PRECIPITATION EXPECTED OTHER THAN A STRAY SPRINKLE OR FLURRY...VFR CONDITIONS ARE FORECAST ACROSS MOST OF THE TERMINALS THROUGH THE TAF PERIOD. THE EXCEPTION IS AT KFKL/KDUJ...WHERE TEMPO GROUPS ARE FORECAST FOR MVFR CEILINGS LATE THIS MORNING. .OUTLOOK.../TUESDAY THROUGH FRIDAY/... A COLD NORTHWESTERLY FLOW WILL LEAD TO POSSIBLE RESTRICTIONS AT KFKL/KDUJ ON TUESDAY AND TUESDAY NIGHT. OTHERWISE...GENERAL VFR CONDITIONS CAN BE EXPECTED THROUGH THURSDAY NIGHT AS HIGH PRESSURE BUILDS OVER THE REGION. A LOW PRESSURE SYSTEM PASSING SOUTH OF THE AREA MAY BRING RAIN TO LOCATIONS SOUTH OF KPIT ON FRIDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS GAYLORD MI
154 PM EDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 422 AM EDT MON APR 1 2013 A SYSTEM IN QUEBEC IS BRINGING COLD AIR AND NORTHWEST WINDS TO THE STATE TODAY. THE COLDER AIR IS PRODUCING LAKE EFFECT SNOW SHOWERS WHICH WILL PERSIST OVER NORTHERN MICHIGAN THROUGH TUESDAY. THE MOST PERSISTENT SNOW SHOWERS WITH THE BEST CHANCE OF ACCUMULATION WILL BE IN THE TYPICAL SNOW BELTS OF NORTHWEST LOWER AND EAST UPPER MICHIGAN. && .UPDATE... ISSUED AT 153 PM EDT MON APR 1 2013 CURRENT FORECAST IS IN LINE. LAKE EFFECT SNOWS CONTINUE OVER NRN MI...AS SFC-850MB WINDS LINGER FROM THE NW AND 850MB TEMPS REMAIN ARND -16C. UPDATE ISSUED AT 951 AM EDT MON APR 1 2013 THE STORM SYSTEM WHICH SWEPT ACROSS THE GREAT LAKES THIS WEEKEND... HAS PUSHED EAST OF THE STATE AND WILL CONTINUE TO LIFT INTO QUEBEC THROUGH TUESDAY. COLD 850MB TEMPS...NORTHWEST WINDS AND LAKE EFFECT SNOWS HAD ALREADY BEGUN TO FILTER INTO NRN MI EARLIER THIS MORNING. 850MB TEMPS DROPPED FROM AROUND 0C SUNDAY AFTERNOON TO ARND -16C BY 12Z THIS MORNING. AS FOR THE REST OF THE AFTN...THE PARAMETERS WHICH ARE CURRENTLY GENERATING LAKE INDUCED SNOWS OVER THE WRN LAKES...ARE NOT EXPECTED TO CHANGE MUCH THROUGH 21Z. 850MB TEMPS WILL LINGER AROUND -16C AS THE AXIS OF THE SFC AND 500MB FEATURES PUSH FURTHER EAST OF THE REGION THIS AFTERNOON. SFC-850MB WINDS WOBBLE DURING THE AFTN...THOUGH REMAIN GENERALLY NW (300-320) WHILE INVERSION HEIGHTS LINGER AROUND 5K FT. OVERALL EXPECT WIDESPREAD LAKE SNOWS TO CONT OVER THE WRN LAKES THROUGH THE AFTN...THOUGH WITH THE HIGH SUN ANGLE...EXPECT DOMINATE SNOW BANDS TO BECOME A LEAST SLIGHTLY DISRUPTED THROUGH THE REST OF THE MORNING. OVERALL WILL KEEP CONT TO MENTION LAKE SNOWS THROUGH THE AFTN. WILL MENTION UP TO 2 INCHES OF SNOW POSSIBLE IN FAVORED SNOW BELTS...AND WILL EXTEND HEADLINES THRU THE AFTN. UPDATE ISSUED AT 708 AM EDT MON APR 1 2013 CHANGES THIS HOUR: ADDITIONAL /UPWARD/ ADJUSTMENTS TO SNOWFALL AS A BAND OF NEARLY 5 INCHES HAS OCCURRED OVER EXTREME SW OTSEGO COUNTY AND NW CRAWFORD COUNTY. BANDING IS MAKING ITS EXPECTED SHIFT EAST...AND IS BEGINNING TO BECOME A LITTLE MORE DIFFUSE. EXPECT WE/VE GOT 2-3 MORE HOURS OF DECENT ACCUMS BEFORE THINGS WIND DOWN. ADVISORY CONTINUES TO LOOK GOOD AND WILL MAKE NO CHANGES TO THIS. UPDATE ISSUED AT 519 AM EDT MON APR 1 2013 CHANGES THIS HOUR: BAND HESITATED LONG ENOUGH FOR ME...AND HAVE ISSUED A WINTER WEATHER ADVISORY FOR 4 OF THE BIG 5 /EXCLUDED KALKASKA/ THROUGH NOON. RADAR ESTIMATES HAVE REACHED 2-3" IN SPOTS...WITH BIG FLUFFY FLAKES FALLING HERE AT THE OFFICE INDICATING 20:1 RATIOS LOOK GOOD. WINDS AMPLE TO BLOW THIS SNOW AROUND AS WELL. EXPECT 2-4 OVER THE NEXT FEW HOURS AS BAND STARTS TO EDGE EAST FROM ITS CURRENT LOCATION...BEFORE LIKELY BREAKING UP BY LATE MORNING. NO OTHER CHANGES ATTM. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 422 AM EDT MON APR 1 2013 HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND GUSTS POSSIBLE ALL MARINE WATERS THROUGH TODAY. SNOW/BLOWING SNOW WILL BRING SOME SLICK TRAVEL AND REDUCED VISIBILITIES TO THE SNOWBELTS OF EASTERN UPPER/NORTHERN LOWER...WITH SNOW SHOWERS REACHING ALL OTHER LOCALES AS WELL. OVERVIEW: WISHING THE EARLY MORNING WATER VAPOR IMAGERY WAS AN APRIL FOOLS JOKE THIS MORNING AS IMPRESSIVE TROUGH CARVES ITSELF OUT OVER THE GREAT LAKES REGION. PICKLE LAKE /ONTARIO/ 00Z RAOB SHOWS -42C AT H5...-25C AT H7 AND -20C AT H8...AN ARCTIC AIRMASS INDEED WITH SURFACE TEMPS UPSTREAM OF THE GREAT LAKES IN THE LOWER TEENS AND DEWPOINTS FALLING TO NEAR ZERO. WITH SUBSTANTIAL DOWNSTREAM BLOCKING IN PLACE FROM GREENLAND SOUTH AND EAST...THE DEVELOPING LONGWAVE TROUGH OVERHEAD WILL BE IN NO HURRY TO DEPART...WITH ITS IMPACTS DOMINATING THE SHORT TERM PORTION OF THE FORECAST. THROUGH DAYBREAK: APX WSR-88D SHOWING LAKE EFFECT SNOW GETTING IT/S ACT TOGETHER OVER NORTHERN LOWER...WITH PRIMARY BAND FROM ACB-GOV STRENGTHENING WITH GOOD LAKE SUPERIOR CONNECTION. EXPECT THIS TREND TO CONTINUE THROUGH DAYBREAK WITH AN INCH OR TWO OF SNOW POSSIBLE OVER THE BIG 5 OF NW LOWER. WILL COVER THIS BAND WITH AN SPS FOR A QUICK 1-2 INCHES WHICH WILL LIKELY IMPACT THE MONDAY MORNING COMMUTE. WINDS REMAIN QUITE BRISK AS 6MB/6HR PRESSURE RISE CENTER OVER NORTHERN LAKE SUPERIOR SLIDES SOUTH AND EAST...WITH 15-25 MPH WINDS THROUGHOUT NORTHERN MICHIGAN...GUSTING AS HIGH AS 35 MPH NEAR THE COASTS. TODAY: WITH THE CORE OF THE H5 LOW PUSHING FROM JUST NORTH OF THE SOO EARLY THIS MORNING TO SOUTHWESTERN QUEBEC BY THSI EVENING...OUR FLOW ALOFT WILL BACK SLIGHTLY AS THE COLDEST AIR ALOFT MAKES ITS CLOSEST APPROACH. T8 AROUND -17C WITH WHAT LOOKS TO BE ROBUST LLEVEL MOISTURE /SEE FOG PRODUCT IMAGERY SHOWING ALL KINDS OF MOISTURE JUST WEST OF THE H5 LOW CENTER /AND THUS...OVERHEAD TODAY/. THIS SPELLS CONTINUED LAKE EFFECT SNOW SHOWERS UNDER STRONG NW WINDS. ALL HIGH RESOLUTION GUIDANCE CONTINUES TO SHOW A DOMINANT BAND TO START THE DAY...WITH THE HRRR LOOKING TO CAPTURE IT/S LOCATION BEST /FURTHER WEST THAN THE RAP AND LOCAL WRF/. GIVEN THAT WE ALREADY HAVE A BAND OF THIS NATURE...SEE NO REASON TO DISAGREE WITH THE GUDIANCE SUGGESTION...WHICH SHOWS THIS BAND STARTING THE DAY CENTERED FROM CVX-ACB-GOV PUSHING EAST GIVEN THE AFOREMENTIONED BACKING FLOW...WITH SOMEWHAT LIGHTER SHSN SURROUNDING IT. THE BAND LOOKS TO BE QUITE MOBILE THROUGH THE MORNING BEFORE CAPE/SHEAR NOMOGRAM SUGGESTS THAT BY LATE MORNING IT WIL BEGIN TO BREAK UP AS OVERLAND INSTABILITY STRENGTHENS. THIS BACKING FLOW SHOULD HELP GET WESTERN CHIPPEWA/MACKINAC BACK INTO THE ACTION DURING THE DAY AS WELL. SNOWFALL: MOBILE SNOWBAND WILL KEEP A LID ON SNOW AMOUNTS...BUT COULD SEE 1-3" FOR THE DAY TODAY OVER THE NW SNOWBELTS...WITH MOST OF THIS FALLING BEFORE ACTIVITY BECOMES MORE CELLULAR THIS AFTERNOON. WHILE WE LOSE HELP FROM ANY ISALLOBARIC COMPONENT TO THE LLEVEL WINDS TODAY...H9 WINDS 25-30KTS AND AMPLE LLEVEL MIXING SUGGEST WINDS 15-25 MPH WINDS WITH GUSTS WELL INTO THE 30S...PARTICULARLY NEAR THE LAKESHORES AND OVER EASTERN UPPER. TEMPS WILL BE VERY SLOW TO CLIMB WITH T9 AROUND -10C SUGGESTING MID 20S /SOME 20F BELOW NORMAL/ WILL BE ABOUT ALL WE CAN MUSTER. WITH THE STRONG WINDS...WIND CHILLS WILL REMAIN IN THE TEENS THROUGH THE DAY. HEADLINES: WILL GO AHEAD AND DROP WINTER WEATHER ADVISORY FOR CHIPPEWA GIVEN LOCATION OF SNOWFALL ACTIVITY WELL WEST OF COUNTY WITH ACCUMS THUS FAR NOT SUFFICIENT TO WARRANT THE HEADLINE. AS DISCUSSED ABOVE...HEAVIEST SNOW IS NOW OVER THE BIG 5 IN NW LOWER...AND WILL MONITOR FOR POTENTIAL HEADLINE THROUGH DAYBREAK...ALTHOUGH EXPECTATION IS THAT THE BAND WILL BEGIN TO MOVE...REDUCING THE THREAT OF SIGNIFICANT ACCUMS. TONIGHT: SYNOPTIC MOISTURE BEGINS TO SLOWLY ERODE WITH TEMPS ALOFT STEADY OR JUST SLIGHTLY WARING UNDER A FAIRLY STEADY 300-310 FLOW REGIME. SOME RESIDUAL LAND-BASED CAPE CONTINUES THROUGH THE OVERNIGHT WHICH MAY NOT FULLY ALLOW THE LAKE EFFECT TO RE-SOLIDIFY INTO BANDS. SHSN WILL CERTAINLY CONTINUE...HOWEVER...WITH ADDITIONAL LIGHT ACCUMULATIONS LIKELY. INHERITED ACCUMS OF 1-2 INCHES /PERHAPS 3 OVER WESTERN CHIPPEWA/ LOOK REASONABLE AND HAVE NO COMPELLING REASON TO DEVIATE SIGNIFICANTLY. CLOUDS WILL LIKELY KEEP TEMPERATURES FROM FALLING ALL THAT FAR... GENERALLY IN THE UPPER TEENS TO AROUND 20. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 422 AM EDT MON APR 1 2013 TUESDAY...AS THE SFC HIGH BEGINS TO MOVE INTO THE REGION, THE 850 MB TEMPERATURES BEGIN TO WARM SLIGHTLY, JUST ENOUGH THAT WE MAY LOSE THE INSTABILITY NEEDED FOR THE LES. THE MOISTURE IN THE 850-700 MB LAYER FALLS OFF TO BELOW 60% ON ALL THE MODELS SO WOULD EXPECT LIGHT SNOW AND FLURRIES. ALTHOUGH WILL HAVE LIKELY POPS SINCE MEASURABLE SNOW IS EXPECTED FROM THIS PATTERN IN THE MORNING. BY THE AFTERNOON, THE MOISTURE CONTINUES TO FALL OFF IN THE 850-700 MB LAYER. THE ONE THING THAT I HAVE NOTICED ABOUT THESE LATE SEASON LES EVENTS IS THAT IT HAS BECOME HARD FOR THE LOWER END OF THE SOUNDINGS TO SATURATE. THIS HAS BEEN LEADING TO INVERTED V SOUNDINGS AND REALIZING LESS SNOW THAN WE WOULD HAVE EVEN A MONTH AGO DURING THE AFTERNOON. TUESDAY NIGHT...AS THE RIDGE BUILDS INTO THE REGION, THE DRIER AIR REALLY BEGINS TO OVERWHELM THE REGION, SHUTTING OFF MOST OF THE SNOW LEAVING ONLY CHANCE POPS IN THE EVENING IN E UPPER, WHILE N LOWER WILL BE DRY ENOUGH TO NOT HAVE ANY SNOW. WEDNESDAY...HIGH PRESSURE AT THE SFC AND 500 MB RIDGE MOVES THROUGH THE REGION SO THAT WE WILL REMAIN DRY FOR THE DAY. OVERNIGHT, A COLD FRONT AND 500 MB SHORTWAVE TROUGH MOVE INTO THE REGION. THE GFS IS A LITTLE FASTER THAN THE ECMWF AND NAM. WILL HOLD OFF THE SNOW BY ALLOWING IT TO JUST TOUCH E UPPER BY 12Z. EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, THE MODELS DRY THINGS OUT WITH THE FRONTAL PASSAGE DURING THE DAY. SO WILL HAVE CHANCE POPS WITH A MIX OF THE RAIN AND SNOW IN E UPPER AND JUST RAIN IN N LOWER. WITH THE SFC TEMPERATURES IN THE 40S, WOULD NOT BE SURPRISED IF THIS TURNS OUT TO BE FLURRIES AND SPRINKLES. FRIDAY, THE HIGH BUILDS INTO THE UPPER GREAT LAKES REGION AND DRIES THINGS OUT AGAIN. SO DRY WEATHER WILL BE EXPECTED. SATURDAY, THE WARM FRONT WILL BE MOVING INTO THE REGION. THE ECMWF HAS THE WARM AIR INTO E UPPER SO THAT IT COULD BE ALL RAIN, WHILE THE GFS HAS IT PLACED A LITTLE SOUTH. PUT THE DIVIDING LINE AT THE STRAITS SINCE THAT SEEMED TO BE THE MIDDLE GROUND. WHICH WOULD CONTINUE THROUGH THE NIGHT AS THE SYSTEM MOVES EAST. SUNDAY, THE LOW MOVES EAST OF THE REGION AND THE COLD AIR MOVES BACK IN ALLOWING FOR A CHANGE OVER TO SNOW. THE GFS DRIES THINGS OUT. WILL LEAN TOWARD THE ECMWF WHICH WOULD BE THE PESSIMISTIC FORECAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 153 PM EDT MON APR 1 2013 MVFR CIGS WILL CONTINUE OVR NRN MI THRU THE TAF PERIOD...A RESULT OF COLD NORTHWEST FLOW ON THE BACKSIDE OF A SYSTEM WOBBLING OVER QUEBEC. 850MB TEMPS WILL BE COLD ENOUGH TO GENERATE LAKE SNOWS OVER NRN MI TAF SITES INTO TUESDAY AFTN. THE MOST PERSISTENT LAKE SNOWS AND OCCASIONAL IFR VSBYS...WILL INFLUENCE TAF SITES KPLN AND KTVC INTO TUESDAY AFTN. && .MARINE... ISSUED AT 422 AM EDT MON APR 1 2013 UPDATE AT 708 AM...DROPPED GALE WARNINGS FOR ALL AREAS SAVE WHITEFISH BAY AND THE COAST OF NORTHERN LAKE HURON. HIGH END SMALL CRAFTS SHOULD SUFFICE THROUGH TODAY AND WILL NEED EXTENDING BEYOND TONIGHT IN SUBSEQUENT UPDATES. SUMMARY: STRONG NORTHWESTERLY WINDS TO CONTINUE THROUGH TUESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. HIGH PRESSURE ARRIVES BY MIDWEEK WITH QUIETER CONDITIONS EXPECTED. HEADLINES: MARGINAL GALES WILL BE ALLOWED TO CONTINUE ALL ZONES THROUGH THIS EVENING. SMALL CRAFTS WILL CERTAINLY BE NEEDED BEYOND THIS...WITH ADDITIONAL GALE FORCE GUSTS POSSIBLE AGAIN TUESDAY...PARTICULARLY FOR NORTHWESTERLY FLOW FAVORED REGIONS. BEYOND THIS...NEXT ROUND OF SMALL CRAFTS LOOKS LIKELY BY WEDNESDAY NIGHT OVER LAKE MICHIGAN AS SOUTHWESTERLY WINDS STRENGTHEN AHEAD OF NEXT APPROACHING SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR MIZ015>017-019-021>023-027-028. LH...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LHZ345-346- 349. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LHZ347-348. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ323-341- 342-344>346. LS...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LSZ322. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ321. && $$ UPDATE...SR SYNOPSIS...JL SHORT TERM...ARNOTT LONG TERM...JL AVIATION...SR MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
126 PM EDT MON APR 1 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 440 AM EDT MON APR 1 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF CENTERED FM HUDSON BAY INTO THE GRT LKS DOWNSTREAM OF UPR RDG OVER WRN CANADA. 00Z H5/H85 TEMPS ARE AS LO AS -42C/-20C AT THE CORE OF THE COLDEST AIR AT YPL. CYC NNW FLOW ON THE WRN FLANK OF LO PRES MOVING SLOWLY E INTO QUEBEC IS DRAWING THIS VERY COLD AIR SWD INTO THE UPR LKS OVER THE RELATIVELY WARM WATERS OF LAKE SUP...WITH THE RESULT NMRS LES BANDS AS SHOWN ON MQT RADAR. WELL DEFINED AXIS OF COLDER CLD TOPS AS SHOWN ON IR STLT IMAGERY IS PRESENT OVER THE E HALF OF THE LK AND ASSOCIATED WITH FAIRLY SHARP H7-3 QVECTOR CNVGC. THIS AXIS OF DEEPER MSTR HAS CAUSED SOME ENHANCEMENT TO THE SHSN. THE HEAVIEST BAND IS STREAMING INTO CENTRAL ALGER COUNTY/SCHOOLCRAFT COUTY...WITH SOME RETURNS AOA 30 DBZ AT 06Z. SN UNDER THIS BAND IS LIKELY FALLING AT THE RATE OF AT LEAST AN INCH/HR GIVEN FAVORABLE LOCATION OF UVV MAX WITHIN DGZ AS SHOWN BY PROFILE FM LOCAL HI RES MODEL. SINCE THE COLDER CLD TOPS ARE TENDING TO DRIFT TO THE E AND DRIER LLVL AIR SHOWN ON THE 00Z INL RAOB IS PRESSING TO THE E... DROPPING THE SFC DEWPT TO NEAR 7F AT IWD AT 06Z...THE INTENSITY OF THE LES W OF MQT HAS TENDED TO DIMINISH OVER TIME PER RADAR TRENDS EVEN THOUGH IR STLT IMAGERY INDICATES SOME LES BANDS OVER THE W HALF OF THE LK THAT HAVE FORMED IN THE PRESENCE OF NOCTURNAL COOLING THAT IS SO IMPORTANT TO ACHIEVE BETTER LES BAND STRUCTURE THIS TIME OF YEAR. NW WINDS ARE STILL GUSTING AS HI AS 40 KTS AT STANNARD ROCK AS OF 06Z...BUT PASSAGE OF PRES RISE CENTER TRAILING THE SFC LO INTO ONTARIO E OF LK SUP HAS CAUSED A SLOW DIMINISHING TREND TO THE WINDS. MAIN FCST CONCERNS THIS PACKAGE ARE LES TRENDS/GOIND HEADLINES. TODAY...MODELS INDICATE UPR TROF AXIS WL DRIFT SLOWLY TO THE E. AREA OF DEEP LYR QVECTOR CNVGC ENHANCING COMMA HEAD/COLDER CLD TOPS NOW OVER THE E HALF OF LK SUP IS PROGGED TO DRIFT INTO ONTARIO IN THE 09Z-12Z TIME FRAME. IN CONCERT WITH THE ARRIVAL OF SOME DRYING FM THE W...LES INTENSITY/COVERAGE SHUD DIMINISH BY SUNRISE. BUT GIVEN PERSISTENCE OF SGNFT BAND OVER CENTRAL ALGER COUNTY INTO NRN SCHOOLCRAFT COUNTY IN PERSISTENT NNW FLOW THRU THE EARLY MRNG HRS...FVRBL SN/WATER RATIOS UNDER COLDEST H85 TEMPS...AND HIER RES MODEL FCSTS THAT SHOWING FAIRLY HI QPF THRU 18Z WITH DEEPER MSTR PERSISTING LONGEST IN THAT AREA CLOSER TO DEPARTING LO...OPTED TO UPGRADE GOING ADVY FOR THOSE ZONES TO AN LES WARNING. OTRW...RISING H5 HGTS/DEEP LYR QVECTOR CNVGC/SUBSIDENCE IN THE PRESENCE OF DIURNAL HEATING THAT TENDS TO DISRUPT THE LES PROCESS IN EARLY SPRING SHOULD CAUSE THE LES BANDS TO WEAKEN AND TRANSITION TO A MORE BLOTCHY APPEARANCE. SLOWLY BACKING FLOW TOWARD MORE WNW BY THE LATE IN THE DAY WL ALSO CAUSE AREA OF HEAVIER SHSN TO SHIFT. ADDITIONAL SN AMOUNTS OVER THE W WL BE LIGHT WITH LLVL DRY AIR HAVING A MORE SGNFT IMPACT THERE AND MODELS HINTING TOWARD A TRANSITION TO LLVL ACYC FLOW IN THE AFTN. TONIGHT...STEADILY RISING HGTS/DEEP LYR QVECTOR CNVGC THAT DROPS FCST INVRN BASE TOWARD 5-6K FT OVER EVEN THE E SUG LES INTENSITY WL BE SOMEWHAT DIMINISHED EVEN THOUGH PERSISTENT NW FLOW/H85 TEMPS IN THE -16 TO -17C RANGE WL ALLOW FOR CONTINUED WDSPRD LES...ESPECIALLY AFTER MID EVNG WHEN IMPACTS OF DAYTIME HEATING WOULD TEND TO SUBSIDE. WITH INVRN BASE OVER THE W FALLING TO ARND 4K FT OVER THE W...SHSN INTENSITY IN THIS AREA WL BE WEAKER WITH SHORTER FETCH/LESS MODERATION OF UPSTREAM AIRMASS. BUT STILL WENT WITH LIKELY POPS GIVEN FVRBL NW FLOW/OVERWATER INSTABILITY/NOCTURNAL COOLING THAT WL ALLOW LES BANDS TO REDEVELOP. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 440 AM EDT MON APR 1 2013 DESPITE ADEQUATE DELTA TS PERSISTING INTO TUESDAY FOR LAKE EFFECT...SFC-H85 FLOW WILL BECOME INCREASINGLY ANTICYCLONIC THROUGH THE DAY. IN ADDITION...INVERSION HEIGHTS BEGIN TO FALL OFF SIGNIFICANTLY BELOW 5KFT. THUS...EXPECT OVERALL COVERAGE AND INTENSITY OF LAKE EFFECT TO BE ON THE WANE AS THE DAY PROGRESSES. TEMPERATURES WILL REMAIN WELL BELOW NORMAL WITH A SIGNIFICANT AMOUNT OF CLOUDINESS DOWNWIND OF LAKE SUPERIOR. LAKE CLOUDS AND EVEN A FEW FLURRIES WILL PERSIST INTO THE MORNING WEDNESDAY OVER THE EAST. AS SURFACE RIDGE AXIS MOVES OVERHEAD THROUGH THE DAY EXPECT SKIES TO BECOME MOSTLY SUNNY AREA WIDE. TEMPERATURES SHOULD REBOUND BACK ABOVE FREEZING AND EVEN APPROACH 40 ACROSS THE WEST WITH WARM ADVECTION INCREASING DURING THE AFTERNOON AND MORE SUNSHINE. MODELS COMING INTO BETTER AGREEMENT WITH THE TIMING OF THE NEXT SHORTWAVE AND SFC TROUGH EXPECTED TO MOVE ACROSS THE AREA WED NIGHT/THU. THE TREND HAS BEEN TOWARD QUICKER MOVEMENT WITH THE TROUGH. SYSTEM IS FAIRLY MOISTURE STARVED...SO DESPITE PRECIP TYPE BEING A CHALLENGE BETWEEN RAIN AND SNOW...AMOUNTS WILL BE LIGHT ENOUGH TO BE PRETTY INSIGNIFICANT. COLD ADVECTION BEHIND THE TROUGH SHOULD PUSH 85H TEMPS BACK DOWN TO THE -10 TO -14C RANGE BY FRIDAY. PROBABLY NOT QUITE COLD ENOUGH FOR LAKE EFFECT THIS TIME AROUND...BUT COLDER AIR WILL KEEP DAYTIME TEMPS BELOW AVERAGE ONLY IN THE 30S. FORECAST FOR NEXT WEEKEND STILL PRETTY CHALLENGING...BUT MODELS SHOWING SOME SIGNS THAT THEY ARE TRYING TO CONVERGE ON A MORE PROBABLE OUTCOME. SHORTWAVE ENERGY AND ASSOCIATED SURFACE LOW MOVING OUT OF THE PLAINS LOOKING LIKE THEY MAY NOW TRACK THROUGH THE LOWER LAKES WHICH WOULD STILL RESULT IN SOME LIGHT SNOWFALL ACROSS SOUTHERN AREAS SATURDAY INTO SUNDAY BUT SPARE THE AREA FROM A MORE SIGNIFICANT STORM. IT IS STILL SOMETHING TO KEEP AN EYE ON AS WE HEAD THROUGH THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 125 PM EDT MON APR 1 2013 DRY AIR MOVING ACROSS LAKE SUPERIOR SHOULD HELP TO KEEP CMX AND IWD AT OR ABOVE MVFR THROUGH THE TAF PERIOD. CEILINGS SHOULD REMAIN AT OR ABOVE 3KFT FOR EACH TAF SITE...WITH KSAW POSSIBLY REACHING VFR CEILINGS THIS AFTERNOON AND EVENING AS WNW WINDS ALLOW FOR DOWNSLOPING OVER THAT AREA. VISIBILITIES ARE A BIT TRICKY AS INTERMITTENT SNOW SHOWERS PASS OVER EACH TAF SITE...OCCASIONALLY REDUCING VISIBILITY TO MVFR OR LOWER AT TIMES...ESPECIALLY OVER THE KEWEENAW WHERE WINDS MAY REMAIN GUSTY THROUGH THE TAF PERIOD INCREASING THE POTENTIAL FOR BLOWING SNOW. WINDS ARE EXPECTED TO DECREASE OVER THE REMAINING TAF SITES AS PRESSURE GRADIENT IS REDUCED AS THE SURFACE LOW SHIFTS TO CENTRAL QUEBEC BY TUESDAY MORNING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 440 AM EDT MON APR 1 2013 AS LO PRES OVER SE CANADA CONTINUES TO THE E AND THE PRES GRADIENT WEAKENS...EXPECT NW WINDS TO SLOWLY DIMINISH AND BELOW GALE FORCE OVER THE CENTRAL BY MID MORNING...SO HASTENED THE ENDING OF THE GALE WARNINGS FOR THIS AREA. ALTHOUG NW GALES TO 35 KTS WILL CONTINUE LONGER OVER THE E INTO THIS EVENING...ENDED THE GALES FOR THAT AREA EARLIER AS WELL. WINDS/WAVES WILL BE SUFFICIENT TO MAINTAIN FREEZING SPRAY OVER AT LEAST THE E HALF THRU TONIGHT. WINDS WILL REMAIN PRETTY GUSTY UP TO 30 KNOTS OVER THE EASTERN LAKE THROUGH THE DAY ON TUESDAY...BUT AS SURFACE RIDGE AXIS PUSHES IN FROM THE WEST PRESSURE GRADIENT WILL RELAX AND WINDS WILL DIMINISH DURING THE EVENING. UNTIL THAT TIME...FREEZING SPRAY SHOULD CONTINUE ACROSS THE EASTERN LAKE. AFTER A BRIEF RESPITE ON WEDNESDAY...SOUTHWESTERLY WINDS UP TO 25 KNOTS AHEAD OF THE NEXT TROUGH CROSSING THE LAKE WILL INCREASE WEDNESDAY NIGHT INTO EARLY THURSDAY BEFORE SHIFTING TO THE NORTHWEST DURING THE DAY THURSDAY INTO THURSDAY NIGHT. WINDS FOR FRIDAY INTO NEXT WEEKEND SHOULD BE BELOW 20 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006-085. WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007. LAKE SUPERIOR... GALE WARNING UNTIL 2 AM EDT TUESDAY FOR LSZ250-251-266-267. GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MZ AVIATION...KEC MARINE...KC/MZ
AREA FORECAST DISCUSSION
NWS GAYLORD MI
952 AM EDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 422 AM EDT MON APR 1 2013 A SYSTEM IN QUEBEC IS BRINGING COLD AIR AND NORTHWEST WINDS TO THE STATE TODAY. THE COLDER AIR IS PRODUCING LAKE EFFECT SNOW SHOWERS WHICH WILL PERSIST OVER NORTHERN MICHIGAN THROUGH TUESDAY. THE MOST PERSISTENT SNOW SHOWERS WITH THE BEST CHANCE OF ACCUMULATION WILL BE IN THE TYPICAL SNOW BELTS OF NORTHWEST LOWER AND EAST UPPER MICHIGAN. && .UPDATE... ISSUED AT 951 AM EDT MON APR 1 2013 THE STORM SYSTEM WHICH SWEPT ACROSS THE GREAT LAKES THIS WEEKEND... HAS PUSHED EAST OF THE STATE AND WILL CONTINUE TO LIFT INTO QUEBEC THROUGH TUESDAY. COLD 850MB TEMPS...NORTHWEST WINDS AND LAKE EFFECT SNOWS HAD ALREADY BEGUN TO FILTER INTO NRN MI EARLIER THIS MORNING. 850MB TEMPS DROPPED FROM AROUND 0C SUNDAY AFTERNOON TO ARND -16C BY 12Z THIS MORNING. AS FOR THE REST OF THE AFTN...THE PARAMETERS WHICH ARE CURRENTLY GENERATING LAKE INDUCED SNOWS OVER THE WRN LAKES...ARE NOT EXPECTED TO CHANGE MUCH THROUGH 21Z. 850MB TEMPS WILL LINGER AROUND -16C AS THE AXIS OF THE SFC AND 500MB FEATURES PUSH FURTHER EAST OF THE REGION THIS AFTERNOON. SFC-850MB WINDS WOBBLE DURING THE AFTN...THOUGH REMAIN GENERALLY NW (300-320) WHILE INVERSION HEIGHTS LINGER AROUND 5K FT. OVERALL EXPECT WIDESPREAD LAKE SNOWS TO CONT OVER THE WRN LAKES THROUGH THE AFTN...THOUGH WITH THE HIGH SUN ANGLE...EXPECT DOMINATE SNOW BANDS TO BECOME A LEAST SLIGHTLY DISRUPTED THROUGH THE REST OF THE MORNING. OVERALL WILL KEEP CONT TO MENTION LAKE SNOWS THROUGH THE AFTN. WILL MENTION UP TO 2 INCHES OF SNOW POSSIBLE IN FAVORED SNOW BELTS...AND WILL EXTEND HEADLINES THRU THE AFTN. UPDATE ISSUED AT 708 AM EDT MON APR 1 2013 CHANGES THIS HOUR: ADDITIONAL /UPWARD/ ADJUSTMENTS TO SNOWFALL AS A BAND OF NEARLY 5 INCHES HAS OCCURRED OVER EXTREME SW OTSEGO COUNTY AND NW CRAWFORD COUNTY. BANDING IS MAKING ITS EXPECTED SHIFT EAST...AND IS BEGINNING TO BECOME A LITTLE MORE DIFFUSE. EXPECT WE/VE GOT 2-3 MORE HOURS OF DECENT ACCUMS BEFORE THINGS WIND DOWN. ADVISORY CONTINUES TO LOOK GOOD AND WILL MAKE NO CHANGES TO THIS. UPDATE ISSUED AT 519 AM EDT MON APR 1 2013 CHANGES THIS HOUR: BAND HESITATED LONG ENOUGH FOR ME...AND HAVE ISSUED A WINTER WEATHER ADVISORY FOR 4 OF THE BIG 5 /EXCLUDED KALKASKA/ THROUGH NOON. RADAR ESTIMATES HAVE REACHED 2-3" IN SPOTS...WITH BIG FLUFFY FLAKES FALLING HERE AT THE OFFICE INDICATING 20:1 RATIOS LOOK GOOD. WINDS AMPLE TO BLOW THIS SNOW AROUND AS WELL. EXPECT 2-4 OVER THE NEXT FEW HOURS AS BAND STARTS TO EDGE EAST FROM ITS CURRENT LOCATION...BEFORE LIKELY BREAKING UP BY LATE MORNING. NO OTHER CHANGES ATTM. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 422 AM EDT MON APR 1 2013 HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND GUSTS POSSIBLE ALL MARINE WATERS THROUGH TODAY. SNOW/BLOWING SNOW WILL BRING SOME SLICK TRAVEL AND REDUCED VISIBILITIES TO THE SNOWBELTS OF EASTERN UPPER/NORTHERN LOWER...WITH SNOW SHOWERS REACHING ALL OTHER LOCALES AS WELL. OVERVIEW: WISHING THE EARLY MORNING WATER VAPOR IMAGERY WAS AN APRIL FOOLS JOKE THIS MORNING AS IMPRESSIVE TROUGH CARVES ITSELF OUT OVER THE GREAT LAKES REGION. PICKLE LAKE /ONTARIO/ 00Z RAOB SHOWS -42C AT H5...-25C AT H7 AND -20C AT H8...AN ARCTIC AIRMASS INDEED WITH SURFACE TEMPS UPSTREAM OF THE GREAT LAKES IN THE LOWER TEENS AND DEWPOINTS FALLING TO NEAR ZERO. WITH SUBSTANTIAL DOWNSTREAM BLOCKING IN PLACE FROM GREENLAND SOUTH AND EAST...THE DEVELOPING LONGWAVE TROUGH OVERHEAD WILL BE IN NO HURRY TO DEPART...WITH ITS IMPACTS DOMINATING THE SHORT TERM PORTION OF THE FORECAST. THROUGH DAYBREAK: APX WSR-88D SHOWING LAKE EFFECT SNOW GETTING IT/S ACT TOGETHER OVER NORTHERN LOWER...WITH PRIMARY BAND FROM ACB-GOV STRENGTHENING WITH GOOD LAKE SUPERIOR CONNECTION. EXPECT THIS TREND TO CONTINUE THROUGH DAYBREAK WITH AN INCH OR TWO OF SNOW POSSIBLE OVER THE BIG 5 OF NW LOWER. WILL COVER THIS BAND WITH AN SPS FOR A QUICK 1-2 INCHES WHICH WILL LIKELY IMPACT THE MONDAY MORNING COMMUTE. WINDS REMAIN QUITE BRISK AS 6MB/6HR PRESSURE RISE CENTER OVER NORTHERN LAKE SUPERIOR SLIDES SOUTH AND EAST...WITH 15-25 MPH WINDS THROUGHOUT NORTHERN MICHIGAN...GUSTING AS HIGH AS 35 MPH NEAR THE COASTS. TODAY: WITH THE CORE OF THE H5 LOW PUSHING FROM JUST NORTH OF THE SOO EARLY THIS MORNING TO SOUTHWESTERN QUEBEC BY THSI EVENING...OUR FLOW ALOFT WILL BACK SLIGHTLY AS THE COLDEST AIR ALOFT MAKES ITS CLOSEST APPROACH. T8 AROUND -17C WITH WHAT LOOKS TO BE ROBUST LLEVEL MOISTURE /SEE FOG PRODUCT IMAGERY SHOWING ALL KINDS OF MOISTURE JUST WEST OF THE H5 LOW CENTER /AND THUS...OVERHEAD TODAY/. THIS SPELLS CONTINUED LAKE EFFECT SNOW SHOWERS UNDER STRONG NW WINDS. ALL HIGH RESOLUTION GUIDANCE CONTINUES TO SHOW A DOMINANT BAND TO START THE DAY...WITH THE HRRR LOOKING TO CAPTURE IT/S LOCATION BEST /FURTHER WEST THAN THE RAP AND LOCAL WRF/. GIVEN THAT WE ALREADY HAVE A BAND OF THIS NATURE...SEE NO REASON TO DISAGREE WITH THE GUDIANCE SUGGESTION...WHICH SHOWS THIS BAND STARTING THE DAY CENTERED FROM CVX-ACB-GOV PUSHING EAST GIVEN THE AFOREMENTIONED BACKING FLOW...WITH SOMEWHAT LIGHTER SHSN SURROUNDING IT. THE BAND LOOKS TO BE QUITE MOBILE THROUGH THE MORNING BEFORE CAPE/SHEAR NOMOGRAM SUGGESTS THAT BY LATE MORNING IT WIL BEGIN TO BREAK UP AS OVERLAND INSTABILITY STRENGTHENS. THIS BACKING FLOW SHOULD HELP GET WESTERN CHIPPEWA/MACKINAC BACK INTO THE ACTION DURING THE DAY AS WELL. SNOWFALL: MOBILE SNOWBAND WILL KEEP A LID ON SNOW AMOUNTS...BUT COULD SEE 1-3" FOR THE DAY TODAY OVER THE NW SNOWBELTS...WITH MOST OF THIS FALLING BEFORE ACTIVITY BECOMES MORE CELLULAR THIS AFTERNOON. WHILE WE LOSE HELP FROM ANY ISALLOBARIC COMPONENT TO THE LLEVEL WINDS TODAY...H9 WINDS 25-30KTS AND AMPLE LLEVEL MIXING SUGGEST WINDS 15-25 MPH WINDS WITH GUSTS WELL INTO THE 30S...PARTICULARLY NEAR THE LAKESHORES AND OVER EASTERN UPPER. TEMPS WILL BE VERY SLOW TO CLIMB WITH T9 AROUND -10C SUGGESTING MID 20S /SOME 20F BELOW NORMAL/ WILL BE ABOUT ALL WE CAN MUSTER. WITH THE STRONG WINDS...WIND CHILLS WILL REMAIN IN THE TEENS THROUGH THE DAY. HEADLINES: WILL GO AHEAD AND DROP WINTER WEATHER ADVISORY FOR CHIPPEWA GIVEN LOCATION OF SNOWFALL ACTIVITY WELL WEST OF COUNTY WITH ACCUMS THUS FAR NOT SUFFICIENT TO WARRANT THE HEADLINE. AS DISCUSSED ABOVE...HEAVIEST SNOW IS NOW OVER THE BIG 5 IN NW LOWER...AND WILL MONITOR FOR POTENTIAL HEADLINE THROUGH DAYBREAK...ALTHOUGH EXPECTATION IS THAT THE BAND WILL BEGIN TO MOVE...REDUCING THE THREAT OF SIGNIFICANT ACCUMS. TONIGHT: SYNOPTIC MOISTURE BEGINS TO SLOWLY ERODE WITH TEMPS ALOFT STEADY OR JUST SLIGHTLY WARING UNDER A FAIRLY STEADY 300-310 FLOW REGIME. SOME RESIDUAL LAND-BASED CAPE CONTINUES THROUGH THE OVERNIGHT WHICH MAY NOT FULLY ALLOW THE LAKE EFFECT TO RE-SOLIDIFY INTO BANDS. SHSN WILL CERTAINLY CONTINUE...HOWEVER...WITH ADDITIONAL LIGHT ACCUMULATIONS LIKELY. INHERITED ACCUMS OF 1-2 INCHES /PERHAPS 3 OVER WESTERN CHIPPEWA/ LOOK REASONABLE AND HAVE NO COMPELLING REASON TO DEVIATE SIGNIFICANTLY. CLOUDS WILL LIKELY KEEP TEMPERATURES FROM FALLING ALL THAT FAR... GENERALLY IN THE UPPER TEENS TO AROUND 20. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 422 AM EDT MON APR 1 2013 TUESDAY...AS THE SFC HIGH BEGINS TO MOVE INTO THE REGION, THE 850 MB TEMPERATURES BEGIN TO WARM SLIGHTLY, JUST ENOUGH THAT WE MAY LOSE THE INSTABILITY NEEDED FOR THE LES. THE MOISTURE IN THE 850-700 MB LAYER FALLS OFF TO BELOW 60% ON ALL THE MODELS SO WOULD EXPECT LIGHT SNOW AND FLURRIES. ALTHOUGH WILL HAVE LIKELY POPS SINCE MEASURABLE SNOW IS EXPECTED FROM THIS PATTERN IN THE MORNING. BY THE AFTERNOON, THE MOISTURE CONTINUES TO FALL OFF IN THE 850-700 MB LAYER. THE ONE THING THAT I HAVE NOTICED ABOUT THESE LATE SEASON LES EVENTS IS THAT IT HAS BECOME HARD FOR THE LOWER END OF THE SOUNDINGS TO SATURATE. THIS HAS BEEN LEADING TO INVERTED V SOUNDINGS AND REALIZING LESS SNOW THAN WE WOULD HAVE EVEN A MONTH AGO DURING THE AFTERNOON. TUESDAY NIGHT...AS THE RIDGE BUILDS INTO THE REGION, THE DRIER AIR REALLY BEGINS TO OVERWHELM THE REGION, SHUTTING OFF MOST OF THE SNOW LEAVING ONLY CHANCE POPS IN THE EVENING IN E UPPER, WHILE N LOWER WILL BE DRY ENOUGH TO NOT HAVE ANY SNOW. WEDNESDAY...HIGH PRESSURE AT THE SFC AND 500 MB RIDGE MOVES THROUGH THE REGION SO THAT WE WILL REMAIN DRY FOR THE DAY. OVERNIGHT, A COLD FRONT AND 500 MB SHORTWAVE TROUGH MOVE INTO THE REGION. THE GFS IS A LITTLE FASTER THAN THE ECMWF AND NAM. WILL HOLD OFF THE SNOW BY ALLOWING IT TO JUST TOUCH E UPPER BY 12Z. EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, THE MODELS DRY THINGS OUT WITH THE FRONTAL PASSAGE DURING THE DAY. SO WILL HAVE CHANCE POPS WITH A MIX OF THE RAIN AND SNOW IN E UPPER AND JUST RAIN IN N LOWER. WITH THE SFC TEMPERATURES IN THE 40S, WOULD NOT BE SURPRISED IF THIS TURNS OUT TO BE FLURRIES AND SPRINKLES. FRIDAY, THE HIGH BUILDS INTO THE UPPER GREAT LAKES REGION AND DRIES THINGS OUT AGAIN. SO DRY WEATHER WILL BE EXPECTED. SATURDAY, THE WARM FRONT WILL BE MOVING INTO THE REGION. THE ECMWF HAS THE WARM AIR INTO E UPPER SO THAT IT COULD BE ALL RAIN, WHILE THE GFS HAS IT PLACED A LITTLE SOUTH. PUT THE DIVIDING LINE AT THE STRAITS SINCE THAT SEEMED TO BE THE MIDDLE GROUND. WHICH WOULD CONTINUE THROUGH THE NIGHT AS THE SYSTEM MOVES EAST. SUNDAY, THE LOW MOVES EAST OF THE REGION AND THE COLD AIR MOVES BACK IN ALLOWING FOR A CHANGE OVER TO SNOW. THE GFS DRIES THINGS OUT. WILL LEAN TOWARD THE ECMWF WHICH WOULD BE THE PESSIMISTIC FORECAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 708 AM EDT MON APR 1 2013 SUMMARY: STRONG LOW PRESSURE...DEPARTING INTO EASTERN CANADA WILL CAUSE STRONG NORTHWEST WINDS THROUGH THE UPCOMING TAF PERIOD...WITH OCCASIONAL LAKE EFFECT SNOW SHOWERS IMPACTING THE TAF SITES. RESTRICTIONS: LAKE EFFECT SNOW BANDS DOING A GOOD JOB AVOIDING THE TERMINALS EARLY THIS MORNING. PRIMARY BAND FROM CHARLEVOIX TO GAYLORD WILL START TO BREAK UP AS IT SHIFTS EAST...BUT WILL LIKELY BRING A PERIOD OF MVFR/IFR TO PLN FOR A TIME THIS MORNING. LAKE EFFECT SHSN WILL CONTINUE THIS AFTERNOON...BUT IN A MORE CELLULAR/SCATTERED FASHION...WHICH WILL LIKELY ALLOW TVC/MBL/APN TO REMAIN VFR WHILE PLN DEALS WITH OCCASIONAL MVFR VSBYS-CIGS /WITH PERHAPS VERY BRIEF IFR VSBYS/. SHSN ACTIVITY WILL CONTINUE TONIGHT...BUT WILL AVOID INCLUDING MVFR/IFR RESTRICTIONS IN THIS TAF PACKAGE AS THESE SHSN WILL BE SHORT-LIVED AND CONFIDENCE NOT HIGH ENOUGH ON LOCATION /ALTHOUGH BEST CHANCES WILL LIKELY CONTINUE TO BE AT PLN/ TO INCLUDE. WINDS: NORTHWEST WINDS WILL REACH 18G28KTS FOR THE DAY TODAY BEFORE DIMINISHING TO 10-15KTS TONIGHT. && .MARINE... ISSUED AT 422 AM EDT MON APR 1 2013 UPDATE AT 708 AM...DROPPED GALE WARNINGS FOR ALL AREAS SAVE WHITEFISH BAY AND THE COAST OF NORTHERN LAKE HURON. HIGH END SMALL CRAFTS SHOULD SUFFICE THROUGH TODAY AND WILL NEED EXTENDING BEYOND TONIGHT IN SUBSEQUENT UPDATES. SUMMARY: STRONG NORTHWESTERLY WINDS TO CONTINUE THROUGH TUESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. HIGH PRESSURE ARRIVES BY MIDWEEK WITH QUIETER CONDITIONS EXPECTED. HEADLINES: MARGINAL GALES WILL BE ALLOWED TO CONTINUE ALL ZONES THROUGH THIS EVENING. SMALL CRAFTS WILL CERTAINLY BE NEEDED BEYOND THIS...WITH ADDITIONAL GALE FORCE GUSTS POSSIBLE AGAIN TUESDAY...PARTICULARLY FOR NORTHWESTERLY FLOW FAVORED REGIONS. BEYOND THIS...NEXT ROUND OF SMALL CRAFTS LOOKS LIKELY BY WEDNESDAY NIGHT OVER LAKE MICHIGAN AS SOUTHWESTERLY WINDS STRENGTHEN AHEAD OF NEXT APPROACHING SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ019-021-022- 028. LH...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LHZ345-346- 349. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LHZ347-348. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ323-341- 342-344>346. LS...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LSZ322. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ321. && $$ UPDATE...SR SYNOPSIS...JL SHORT TERM...ARNOTT LONG TERM...JL AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
728 AM EDT MON APR 1 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 440 AM EDT MON APR 1 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF CENTERED FM HUDSON BAY INTO THE GRT LKS DOWNSTREAM OF UPR RDG OVER WRN CANADA. 00Z H5/H85 TEMPS ARE AS LO AS -42C/-20C AT THE CORE OF THE COLDEST AIR AT YPL. CYC NNW FLOW ON THE WRN FLANK OF LO PRES MOVING SLOWLY E INTO QUEBEC IS DRAWING THIS VERY COLD AIR SWD INTO THE UPR LKS OVER THE RELATIVELY WARM WATERS OF LAKE SUP...WITH THE RESULT NMRS LES BANDS AS SHOWN ON MQT RADAR. WELL DEFINED AXIS OF COLDER CLD TOPS AS SHOWN ON IR STLT IMAGERY IS PRESENT OVER THE E HALF OF THE LK AND ASSOCIATED WITH FAIRLY SHARP H7-3 QVECTOR CNVGC. THIS AXIS OF DEEPER MSTR HAS CAUSED SOME ENHANCEMENT TO THE SHSN. THE HEAVIEST BAND IS STREAMING INTO CENTRAL ALGER COUNTY/SCHOOLCRAFT COUTY...WITH SOME RETURNS AOA 30 DBZ AT 06Z. SN UNDER THIS BAND IS LIKELY FALLING AT THE RATE OF AT LEAST AN INCH/HR GIVEN FAVORABLE LOCATION OF UVV MAX WITHIN DGZ AS SHOWN BY PROFILE FM LOCAL HI RES MODEL. SINCE THE COLDER CLD TOPS ARE TENDING TO DRIFT TO THE E AND DRIER LLVL AIR SHOWN ON THE 00Z INL RAOB IS PRESSING TO THE E... DROPPING THE SFC DEWPT TO NEAR 7F AT IWD AT 06Z...THE INTENSITY OF THE LES W OF MQT HAS TENDED TO DIMINISH OVER TIME PER RADAR TRENDS EVEN THOUGH IR STLT IMAGERY INDICATES SOME LES BANDS OVER THE W HALF OF THE LK THAT HAVE FORMED IN THE PRESENCE OF NOCTURNAL COOLING THAT IS SO IMPORTANT TO ACHIEVE BETTER LES BAND STRUCTURE THIS TIME OF YEAR. NW WINDS ARE STILL GUSTING AS HI AS 40 KTS AT STANNARD ROCK AS OF 06Z...BUT PASSAGE OF PRES RISE CENTER TRAILING THE SFC LO INTO ONTARIO E OF LK SUP HAS CAUSED A SLOW DIMINISHING TREND TO THE WINDS. MAIN FCST CONCERNS THIS PACKAGE ARE LES TRENDS/GOIND HEADLINES. TODAY...MODELS INDICATE UPR TROF AXIS WL DRIFT SLOWLY TO THE E. AREA OF DEEP LYR QVECTOR CNVGC ENHANCING COMMA HEAD/COLDER CLD TOPS NOW OVER THE E HALF OF LK SUP IS PROGGED TO DRIFT INTO ONTARIO IN THE 09Z-12Z TIME FRAME. IN CONCERT WITH THE ARRIVAL OF SOME DRYING FM THE W...LES INTENSITY/COVERAGE SHUD DIMINISH BY SUNRISE. BUT GIVEN PERSISTENCE OF SGNFT BAND OVER CENTRAL ALGER COUNTY INTO NRN SCHOOLCRAFT COUNTY IN PERSISTENT NNW FLOW THRU THE EARLY MRNG HRS...FVRBL SN/WATER RATIOS UNDER COLDEST H85 TEMPS...AND HIER RES MODEL FCSTS THAT SHOWING FAIRLY HI QPF THRU 18Z WITH DEEPER MSTR PERSISTING LONGEST IN THAT AREA CLOSER TO DEPARTING LO...OPTED TO UPGRADE GOING ADVY FOR THOSE ZONES TO AN LES WARNING. OTRW...RISING H5 HGTS/DEEP LYR QVECTOR CNVGC/SUBSIDENCE IN THE PRESENCE OF DIURNAL HEATING THAT TENDS TO DISRUPT THE LES PROCESS IN EARLY SPRING SHOULD CAUSE THE LES BANDS TO WEAKEN AND TRANSITION TO A MORE BLOTCHY APPEARANCE. SLOWLY BACKING FLOW TOWARD MORE WNW BY THE LATE IN THE DAY WL ALSO CAUSE AREA OF HEAVIER SHSN TO SHIFT. ADDITIONAL SN AMOUNTS OVER THE W WL BE LIGHT WITH LLVL DRY AIR HAVING A MORE SGNFT IMPACT THERE AND MODELS HINTING TOWARD A TRANSITION TO LLVL ACYC FLOW IN THE AFTN. TONIGHT...STEADILY RISING HGTS/DEEP LYR QVECTOR CNVGC THAT DROPS FCST INVRN BASE TOWARD 5-6K FT OVER EVEN THE E SUG LES INTENSITY WL BE SOMEWHAT DIMINISHED EVEN THOUGH PERSISTENT NW FLOW/H85 TEMPS IN THE -16 TO -17C RANGE WL ALLOW FOR CONTINUED WDSPRD LES...ESPECIALLY AFTER MID EVNG WHEN IMPACTS OF DAYTIME HEATING WOULD TEND TO SUBSIDE. WITH INVRN BASE OVER THE W FALLING TO ARND 4K FT OVER THE W...SHSN INTENSITY IN THIS AREA WL BE WEAKER WITH SHORTER FETCH/LESS MODERATION OF UPSTREAM AIRMASS. BUT STILL WENT WITH LIKELY POPS GIVEN FVRBL NW FLOW/OVERWATER INSTABILITY/NOCTURNAL COOLING THAT WL ALLOW LES BANDS TO REDEVELOP. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 440 AM EDT MON APR 1 2013 DESPITE ADEQUATE DELTA TS PERSISTING INTO TUESDAY FOR LAKE EFFECT...SFC-H85 FLOW WILL BECOME INCREASINGLY ANTICYCLONIC THROUGH THE DAY. IN ADDITION...INVERSION HEIGHTS BEGIN TO FALL OFF SIGNIFICANTLY BELOW 5KFT. THUS...EXPECT OVERALL COVERAGE AND INTENSITY OF LAKE EFFECT TO BE ON THE WANE AS THE DAY PROGRESSES. TEMPERATURES WILL REMAIN WELL BELOW NORMAL WITH A SIGNIFICANT AMOUNT OF CLOUDINESS DOWNWIND OF LAKE SUPERIOR. LAKE CLOUDS AND EVEN A FEW FLURRIES WILL PERSIST INTO THE MORNING WEDNESDAY OVER THE EAST. AS SURFACE RIDGE AXIS MOVES OVERHEAD THROUGH THE DAY EXPECT SKIES TO BECOME MOSTLY SUNNY AREA WIDE. TEMPERATURES SHOULD REBOUND BACK ABOVE FREEZING AND EVEN APPROACH 40 ACROSS THE WEST WITH WARM ADVECTION INCREASING DURING THE AFTERNOON AND MORE SUNSHINE. MODELS COMING INTO BETTER AGREEMENT WITH THE TIMING OF THE NEXT SHORTWAVE AND SFC TROUGH EXPECTED TO MOVE ACROSS THE AREA WED NIGHT/THU. THE TREND HAS BEEN TOWARD QUICKER MOVEMENT WITH THE TROUGH. SYSTEM IS FAIRLY MOISTURE STARVED...SO DESPITE PRECIP TYPE BEING A CHALLENGE BETWEEN RAIN AND SNOW...AMOUNTS WILL BE LIGHT ENOUGH TO BE PRETTY INSIGNIFICANT. COLD ADVECTION BEHIND THE TROUGH SHOULD PUSH 85H TEMPS BACK DOWN TO THE -10 TO -14C RANGE BY FRIDAY. PROBABLY NOT QUITE COLD ENOUGH FOR LAKE EFFECT THIS TIME AROUND...BUT COLDER AIR WILL KEEP DAYTIME TEMPS BELOW AVERAGE ONLY IN THE 30S. FORECAST FOR NEXT WEEKEND STILL PRETTY CHALLENGING...BUT MODELS SHOWING SOME SIGNS THAT THEY ARE TRYING TO CONVERGE ON A MORE PROBABLE OUTCOME. SHORTWAVE ENERGY AND ASSOCIATED SURFACE LOW MOVING OUT OF THE PLAINS LOOKING LIKE THEY MAY NOW TRACK THROUGH THE LOWER LAKES WHICH WOULD STILL RESULT IN SOME LIGHT SNOWFALL ACROSS SOUTHERN AREAS SATURDAY INTO SUNDAY BUT SPARE THE AREA FROM A MORE SIGNIFICANT STORM. IT IS STILL SOMETHING TO KEEP AN EYE ON AS WE HEAD THROUGH THE WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 726 AM EDT MON APR 1 2013 ALTHOUGH NW FLOW OF COLD AIR FLOWING ACRS LK SUP MAY CAUSE MVFR CONDITIONS AT TIMES AT IWD/CMX WITH UPSLOPE WIND COMPONENT...EXPECT VFR CONDITIONS TO PREDOMINATE AT THESE SITES GIVEN VERY DRY NATURE OF THE LLVLS UPSTREAM AS SHOWN ON THE 00Z INL/YQD RAOBS. WITH A DOWNSLOPE WIND COMPONENT AND THIS DRYNESS...SAW HAS THE BEST SHOT TO REMAIN VFR FOR THE ENTIRE TIME. GUSTY NW WINDS WL LINGER... ESPECIALLY AT THE MORE EXPOSED CMX LOCATION. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 440 AM EDT MON APR 1 2013 AS LO PRES OVER SE CANADA CONTINUES TO THE E AND THE PRES GRADIENT WEAKENS...EXPECT NW WINDS TO SLOWLY DIMINISH AND BELOW GALE FORCE OVER THE CENTRAL BY MID MORNING...SO HASTENED THE ENDING OF THE GALE WARNINGS FOR THIS AREA. ALTHOUG NW GALES TO 35 KTS WILL CONTINUE LONGER OVER THE E INTO THIS EVENING...ENDED THE GALES FOR THAT AREA EARLIER AS WELL. WINDS/WAVES WILL BE SUFFICIENT TO MAINTAIN FREEZING SPRAY OVER AT LEAST THE E HALF THRU TONIGHT. WINDS WILL REMAIN PRETTY GUSTY UP TO 30 KNOTS OVER THE EASTERN LAKE THROUGH THE DAY ON TUESDAY...BUT AS SURFACE RIDGE AXIS PUSHES IN FROM THE WEST PRESSURE GRADIENT WILL RELAX AND WINDS WILL DIMINISH DURING THE EVENING. UNTIL THAT TIME...FREEZING SPRAY SHOULD CONTINUE ACROSS THE EASTERN LAKE. AFTER A BRIEF RESPITE ON WEDNESDAY...SOUTHWESTERLY WINDS UP TO 25 KNOTS AHEAD OF THE NEXT TROUGH CROSSING THE LAKE WILL INCREASE WEDNESDAY NIGHT INTO EARLY THURSDAY BEFORE SHIFTING TO THE NORTHWEST DURING THE DAY THURSDAY INTO THURSDAY NIGHT. WINDS FOR FRIDAY INTO NEXT WEEKEND SHOULD BE BELOW 20 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007. LAKE EFFECT SNOW WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006-085. LAKE SUPERIOR... GALE WARNING UNTIL 2 AM EDT TUESDAY FOR LSZ250-251-266-267. GALE WARNING UNTIL NOON EDT TODAY FOR LSZ265. GALE WARNING UNTIL 8 AM EDT THIS MORNING FOR LSZ244-245-264. GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MZ AVIATION...KC MARINE...KC/MZ
AREA FORECAST DISCUSSION...UPDATED
NWS GAYLORD MI
716 AM EDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 422 AM EDT MON APR 1 2013 A SYSTEM IN QUEBEC IS BRINGING COLD AIR AND NORTHWEST WINDS TO THE STATE TODAY. THE COLDER AIR IS PRODUCING LAKE EFFECT SNOW SHOWERS WHICH WILL PERSIST OVER NORTHERN MICHIGAN THROUGH TUESDAY. THE MOST PERSISTENT SNOW SHOWERS WITH THE BEST CHANCE OF ACCUMULATION WILL BE IN THE TYPICAL SNOW BELTS OF NORTHWEST LOWER AND EAST UPPER MICHIGAN. && .UPDATE... ISSUED AT 708 AM EDT MON APR 1 2013 CHANGES THIS HOUR: ADDITIONAL /UPWARD/ ADJUSTMENTS TO SNOWFALL AS A BAND OF NEARLY 5 INCHES HAS OCCURRED OVER EXTREME SW OTSEGO COUNTY AND NW CRAWFORD COUNTY. BANDING IS MAKING ITS EXPECTED SHIFT EAST...AND IS BEGINNING TO BECOME A LITTLE MORE DIFFUSE. EXPECT WE/VE GOT 2-3 MORE HOURS OF DECENT ACCUMS BEFORE THINGS WIND DOWN. ADVISORY CONTINUES TO LOOK GOOD AND WILL MAKE NO CHANGES TO THIS. UPDATE ISSUED AT 519 AM EDT MON APR 1 2013 CHANGES THIS HOUR: BAND HESITATED LONG ENOUGH FOR ME...AND HAVE ISSUED A WINTER WEATHER ADVISORY FOR 4 OF THE BIG 5 /EXCLUDED KALKASKA/ THROUGH NOON. RADAR ESTIMATES HAVE REACHED 2-3" IN SPOTS...WITH BIG FLUFFY FLAKES FALLING HERE AT THE OFFICE INDICATING 20:1 RATIOS LOOK GOOD. WINDS AMPLE TO BLOW THIS SNOW AROUND AS WELL. EXPECT 2-4 OVER THE NEXT FEW HOURS AS BAND STARTS TO EDGE EAST FROM ITS CURRENT LOCATION...BEFORE LIKELY BREAKING UP BY LATE MORNING. NO OTHER CHANGES ATTM. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 422 AM EDT MON APR 1 2013 HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND GUSTS POSSIBLE ALL MARINE WATERS THROUGH TODAY. SNOW/BLOWING SNOW WILL BRING SOME SLICK TRAVEL AND REDUCED VISIBILITIES TO THE SNOWBELTS OF EASTERN UPPER/NORTHERN LOWER...WITH SNOW SHOWERS REACHING ALL OTHER LOCALES AS WELL. OVERVIEW: WISHING THE EARLY MORNING WATER VAPOR IMAGERY WAS AN APRIL FOOLS JOKE THIS MORNING AS IMPRESSIVE TROUGH CARVES ITSELF OUT OVER THE GREAT LAKES REGION. PICKLE LAKE /ONTARIO/ 00Z RAOB SHOWS -42C AT H5...-25C AT H7 AND -20C AT H8...AN ARCTIC AIRMASS INDEED WITH SURFACE TEMPS UPSTREAM OF THE GREAT LAKES IN THE LOWER TEENS AND DEWPOINTS FALLING TO NEAR ZERO. WITH SUBSTANTIAL DOWNSTREAM BLOCKING IN PLACE FROM GREENLAND SOUTH AND EAST...THE DEVELOPING LONGWAVE TROUGH OVERHEAD WILL BE IN NO HURRY TO DEPART...WITH ITS IMPACTS DOMINATING THE SHORT TERM PORTION OF THE FORECAST. THROUGH DAYBREAK: APX WSR-88D SHOWING LAKE EFFECT SNOW GETTING IT/S ACT TOGETHER OVER NORTHERN LOWER...WITH PRIMARY BAND FROM ACB-GOV STRENGTHENING WITH GOOD LAKE SUPERIOR CONNECTION. EXPECT THIS TREND TO CONTINUE THROUGH DAYBREAK WITH AN INCH OR TWO OF SNOW POSSIBLE OVER THE BIG 5 OF NW LOWER. WILL COVER THIS BAND WITH AN SPS FOR A QUICK 1-2 INCHES WHICH WILL LIKELY IMPACT THE MONDAY MORNING COMMUTE. WINDS REMAIN QUITE BRISK AS 6MB/6HR PRESSURE RISE CENTER OVER NORTHERN LAKE SUPERIOR SLIDES SOUTH AND EAST...WITH 15-25 MPH WINDS THROUGHOUT NORTHERN MICHIGAN...GUSTING AS HIGH AS 35 MPH NEAR THE COASTS. TODAY: WITH THE CORE OF THE H5 LOW PUSHING FROM JUST NORTH OF THE SOO EARLY THIS MORNING TO SOUTHWESTERN QUEBEC BY THSI EVENING...OUR FLOW ALOFT WILL BACK SLIGHTLY AS THE COLDEST AIR ALOFT MAKES ITS CLOSEST APPROACH. T8 AROUND -17C WITH WHAT LOOKS TO BE ROBUST LLEVEL MOISTURE /SEE FOG PRODUCT IMAGERY SHOWING ALL KINDS OF MOISTURE JUST WEST OF THE H5 LOW CENTER /AND THUS...OVERHEAD TODAY/. THIS SPELLS CONTINUED LAKE EFFECT SNOW SHOWERS UNDER STRONG NW WINDS. ALL HIGH RESOLUTION GUIDANCE CONTINUES TO SHOW A DOMINANT BAND TO START THE DAY...WITH THE HRRR LOOKING TO CAPTURE IT/S LOCATION BEST /FURTHER WEST THAN THE RAP AND LOCAL WRF/. GIVEN THAT WE ALREADY HAVE A BAND OF THIS NATURE...SEE NO REASON TO DISAGREE WITH THE GUDIANCE SUGGESTION...WHICH SHOWS THIS BAND STARTING THE DAY CENTERED FROM CVX-ACB-GOV PUSHING EAST GIVEN THE AFOREMENTIONED BACKING FLOW...WITH SOMEWHAT LIGHTER SHSN SURROUNDING IT. THE BAND LOOKS TO BE QUITE MOBILE THROUGH THE MORNING BEFORE CAPE/SHEAR NOMOGRAM SUGGESTS THAT BY LATE MORNING IT WIL BEGIN TO BREAK UP AS OVERLAND INSTABILITY STRENGTHENS. THIS BACKING FLOW SHOULD HELP GET WESTERN CHIPPEWA/MACKINAC BACK INTO THE ACTION DURING THE DAY AS WELL. SNOWFALL: MOBILE SNOWBAND WILL KEEP A LID ON SNOW AMOUNTS...BUT COULD SEE 1-3" FOR THE DAY TODAY OVER THE NW SNOWBELTS...WITH MOST OF THIS FALLING BEFORE ACTIVITY BECOMES MORE CELLULAR THIS AFTERNOON. WHILE WE LOSE HELP FROM ANY ISALLOBARIC COMPONENT TO THE LLEVEL WINDS TODAY...H9 WINDS 25-30KTS AND AMPLE LLEVEL MIXING SUGGEST WINDS 15-25 MPH WINDS WITH GUSTS WELL INTO THE 30S...PARTICULARLY NEAR THE LAKESHORES AND OVER EASTERN UPPER. TEMPS WILL BE VERY SLOW TO CLIMB WITH T9 AROUND -10C SUGGESTING MID 20S /SOME 20F BELOW NORMAL/ WILL BE ABOUT ALL WE CAN MUSTER. WITH THE STRONG WINDS...WIND CHILLS WILL REMAIN IN THE TEENS THROUGH THE DAY. HEADLINES: WILL GO AHEAD AND DROP WINTER WEATHER ADVISORY FOR CHIPPEWA GIVEN LOCATION OF SNOWFALL ACTIVITY WELL WEST OF COUNTY WITH ACCUMS THUS FAR NOT SUFFICIENT TO WARRANT THE HEADLINE. AS DISCUSSED ABOVE...HEAVIEST SNOW IS NOW OVER THE BIG 5 IN NW LOWER...AND WILL MONITOR FOR POTENTIAL HEADLINE THROUGH DAYBREAK...ALTHOUGH EXPECTATION IS THAT THE BAND WILL BEGIN TO MOVE...REDUCING THE THREAT OF SIGNIFICANT ACCUMS. TONIGHT: SYNOPTIC MOISTURE BEGINS TO SLOWLY ERODE WITH TEMPS ALOFT STEADY OR JUST SLIGHTLY WARING UNDER A FAIRLY STEADY 300-310 FLOW REGIME. SOME RESIDUAL LAND-BASED CAPE CONTINUES THROUGH THE OVERNIGHT WHICH MAY NOT FULLY ALLOW THE LAKE EFFECT TO RE-SOLIDIFY INTO BANDS. SHSN WILL CERTAINLY CONTINUE...HOWEVER...WITH ADDITIONAL LIGHT ACCUMULATIONS LIKELY. INHERITED ACCUMS OF 1-2 INCHES /PERHAPS 3 OVER WESTERN CHIPPEWA/ LOOK REASONABLE AND HAVE NO COMPELLING REASON TO DEVIATE SIGNIFICANTLY. CLOUDS WILL LIKELY KEEP TEMPERATURES FROM FALLING ALL THAT FAR... GENERALLY IN THE UPPER TEENS TO AROUND 20. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 422 AM EDT MON APR 1 2013 TUESDAY...AS THE SFC HIGH BEGINS TO MOVE INTO THE REGION, THE 850 MB TEMPERATURES BEGIN TO WARM SLIGHTLY, JUST ENOUGH THAT WE MAY LOSE THE INSTABILITY NEEDED FOR THE LES. THE MOISTURE IN THE 850-700 MB LAYER FALLS OFF TO BELOW 60% ON ALL THE MODELS SO WOULD EXPECT LIGHT SNOW AND FLURRIES. ALTHOUGH WILL HAVE LIKELY POPS SINCE MEASURABLE SNOW IS EXPECTED FROM THIS PATTERN IN THE MORNING. BY THE AFTERNOON, THE MOISTURE CONTINUES TO FALL OFF IN THE 850-700 MB LAYER. THE ONE THING THAT I HAVE NOTICED ABOUT THESE LATE SEASON LES EVENTS IS THAT IT HAS BECOME HARD FOR THE LOWER END OF THE SOUNDINGS TO SATURATE. THIS HAS BEEN LEADING TO INVERTED V SOUNDINGS AND REALIZING LESS SNOW THAN WE WOULD HAVE EVEN A MONTH AGO DURING THE AFTERNOON. TUESDAY NIGHT...AS THE RIDGE BUILDS INTO THE REGION, THE DRIER AIR REALLY BEGINS TO OVERWHELM THE REGION, SHUTTING OFF MOST OF THE SNOW LEAVING ONLY CHANCE POPS IN THE EVENING IN E UPPER, WHILE N LOWER WILL BE DRY ENOUGH TO NOT HAVE ANY SNOW. WEDNESDAY...HIGH PRESSURE AT THE SFC AND 500 MB RIDGE MOVES THROUGH THE REGION SO THAT WE WILL REMAIN DRY FOR THE DAY. OVERNIGHT, A COLD FRONT AND 500 MB SHORTWAVE TROUGH MOVE INTO THE REGION. THE GFS IS A LITTLE FASTER THAN THE ECMWF AND NAM. WILL HOLD OFF THE SNOW BY ALLOWING IT TO JUST TOUCH E UPPER BY 12Z. EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, THE MODELS DRY THINGS OUT WITH THE FRONTAL PASSAGE DURING THE DAY. SO WILL HAVE CHANCE POPS WITH A MIX OF THE RAIN AND SNOW IN E UPPER AND JUST RAIN IN N LOWER. WITH THE SFC TEMPERATURES IN THE 40S, WOULD NOT BE SURPRISED IF THIS TURNS OUT TO BE FLURRIES AND SPRINKLES. FRIDAY, THE HIGH BUILDS INTO THE UPPER GREAT LAKES REGION AND DRIES THINGS OUT AGAIN. SO DRY WEATHER WILL BE EXPECTED. SATURDAY, THE WARM FRONT WILL BE MOVING INTO THE REGION. THE ECMWF HAS THE WARM AIR INTO E UPPER SO THAT IT COULD BE ALL RAIN, WHILE THE GFS HAS IT PLACED A LITTLE SOUTH. PUT THE DIVIDING LINE AT THE STRAITS SINCE THAT SEEMED TO BE THE MIDDLE GROUND. WHICH WOULD CONTINUE THROUGH THE NIGHT AS THE SYSTEM MOVES EAST. SUNDAY, THE LOW MOVES EAST OF THE REGION AND THE COLD AIR MOVES BACK IN ALLOWING FOR A CHANGE OVER TO SNOW. THE GFS DRIES THINGS OUT. WILL LEAN TOWARD THE ECMWF WHICH WOULD BE THE PESSIMISTIC FORECAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 708 AM EDT MON APR 1 2013 SUMMARY: STRONG LOW PRESSURE...DEPARTING INTO EASTERN CANADA WILL CAUSE STRONG NORTHWEST WINDS THROUGH THE UPCOMING TAF PERIOD...WITH OCCASIONAL LAKE EFFECT SNOW SHOWERS IMPACTING THE TAF SITES. RESTRICTIONS: LAKE EFFECT SNOW BANDS DOING A GOOD JOB AVOIDING THE TERMINALS EARLY THIS MORNING. PRIMARY BAND FROM CHARLEVOIX TO GAYLORD WILL START TO BREAK UP AS IT SHIFTS EAST...BUT WILL LIKELY BRING A PERIOD OF MVFR/IFR TO PLN FOR A TIME THIS MORNING. LAKE EFFECT SHSN WILL CONTINUE THIS AFTERNOON...BUT IN A MORE CELLULAR/SCATTERED FASHION...WHICH WILL LIKELY ALLOW TVC/MBL/APN TO REMAIN VFR WHILE PLN DEALS WITH OCCASIONAL MVFR VSBYS-CIGS /WITH PERHAPS VERY BRIEF IFR VSBYS/. SHSN ACTIVITY WILL CONTINUE TONIGHT...BUT WILL AVOID INCLUDING MVFR/IFR RESTRICTIONS IN THIS TAF PACKAGE AS THESE SHSN WILL BE SHORT-LIVED AND CONFIDENCE NOT HIGH ENOUGH ON LOCATION /ALTHOUGH BEST CHANCES WILL LIKELY CONTINUE TO BE AT PLN/ TO INCLUDE. WINDS: NORTHWEST WINDS WILL REACH 18G28KTS FOR THE DAY TODAY BEFORE DIMINISHING TO 10-15KTS TONIGHT. && .MARINE... ISSUED AT 422 AM EDT MON APR 1 2013 UPDATE AT 708 AM...DROPPED GALE WARNINGS FOR ALL AREAS SAVE WHITEFISH BAY AND THE COAST OF NORTHERN LAKE HURON. HIGH END SMALL CRAFTS SHOULD SUFFICE THROUGH TODAY AND WILL NEED EXTENDING BEYOND TONIGHT IN SUBSEQUENT UPDATES. SUMMARY: STRONG NORTHWESTERLY WINDS TO CONTINUE THROUGH TUESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. HIGH PRESSURE ARRIVES BY MIDWEEK WITH QUIETER CONDITIONS EXPECTED. HEADLINES: MARGINAL GALES WILL BE ALLOWED TO CONTINUE ALL ZONES THROUGH THIS EVENING. SMALL CRAFTS WILL CERTAINLY BE NEEDED BEYOND THIS...WITH ADDITIONAL GALE FORCE GUSTS POSSIBLE AGAIN TUESDAY...PARTICULARLY FOR NORTHWESTERLY FLOW FAVORED REGIONS. BEYOND THIS...NEXT ROUND OF SMALL CRAFTS LOOKS LIKELY BY WEDNESDAY NIGHT OVER LAKE MICHIGAN AS SOUTHWESTERLY WINDS STRENGTHEN AHEAD OF NEXT APPROACHING SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ019-021-022- 028. LH...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LHZ345-346- 349. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LHZ347-348. LM...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LMZ323-341- 342-344>346. LS...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR LSZ322. GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ321. && $$ UPDATE...ARNOTT SYNOPSIS...JL SHORT TERM...ARNOTT LONG TERM...JL AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION...UPDATED
NWS GAYLORD MI
523 AM EDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 422 AM EDT MON APR 1 2013 A SYSTEM IN QUEBEC IS BRINGING COLD AIR AND NORTHWEST WINDS TO THE STATE TODAY. THE COLDER AIR IS PRODUCING LAKE EFFECT SNOW SHOWERS WHICH WILL PERSIST OVER NORTHERN MICHIGAN THROUGH TUESDAY. THE MOST PERSISTENT SNOW SHOWERS WITH THE BEST CHANCE OF ACCUMULATION WILL BE IN THE TYPICAL SNOW BELTS OF NORTHWEST LOWER AND EAST UPPER MICHIGAN. && .UPDATE... ISSUED AT 519 AM EDT MON APR 1 2013 CHANGES THIS HOUR: BAND HESITATED LONG ENOUGH FOR ME...AND HAVE ISSUED A WINTER WEATHER ADVISORY FOR 4 OF THE BIG 5 /EXCLUDED KALKASKA/ THROUGH NOON. RADAR ESTIMATES HAVE REACHED 2-3" IN SPOTS...WITH BIG FLUFFY FLAKES FALLING HERE AT THE OFFICE INDICATING 20:1 RATIOS LOOK GOOD. WINDS AMPLE TO BLOW THIS SNOW AROUND AS WELL. EXPECT 2-4 OVER THE NEXT FEW HOURS AS BAND STARTS TO EDGE EAST FROM ITS CURRENT LOCATION...BEFORE LIKELY BREAKING UP BY LATE MORNING. NO OTHER CHANGES ATTM. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 422 AM EDT MON APR 1 2013 HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND GUSTS POSSIBLE ALL MARINE WATERS THROUGH TODAY. SNOW/BLOWING SNOW WILL BRING SOME SLICK TRAVEL AND REDUCED VISIBILITIES TO THE SNOWBELTS OF EASTERN UPPER/NORTHERN LOWER...WITH SNOW SHOWERS REACHING ALL OTHER LOCALES AS WELL. OVERVIEW: WISHING THE EARLY MORNING WATER VAPOR IMAGERY WAS AN APRIL FOOLS JOKE THIS MORNING AS IMPRESSIVE TROUGH CARVES ITSELF OUT OVER THE GREAT LAKES REGION. PICKLE LAKE /ONTARIO/ 00Z RAOB SHOWS -42C AT H5...-25C AT H7 AND -20C AT H8...AN ARCTIC AIRMASS INDEED WITH SURFACE TEMPS UPSTREAM OF THE GREAT LAKES IN THE LOWER TEENS AND DEWPOINTS FALLING TO NEAR ZERO. WITH SUBSTANTIAL DOWNSTREAM BLOCKING IN PLACE FROM GREENLAND SOUTH AND EAST...THE DEVELOPING LONGWAVE TROUGH OVERHEAD WILL BE IN NO HURRY TO DEPART...WITH ITS IMPACTS DOMINATING THE SHORT TERM PORTION OF THE FORECAST. THROUGH DAYBREAK: APX WSR-88D SHOWING LAKE EFFECT SNOW GETTING IT/S ACT TOGETHER OVER NORTHERN LOWER...WITH PRIMARY BAND FROM ACB-GOV STRENGTHENING WITH GOOD LAKE SUPERIOR CONNECTION. EXPECT THIS TREND TO CONTINUE THROUGH DAYBREAK WITH AN INCH OR TWO OF SNOW POSSIBLE OVER THE BIG 5 OF NW LOWER. WILL COVER THIS BAND WITH AN SPS FOR A QUICK 1-2 INCHES WHICH WILL LIKELY IMPACT THE MONDAY MORNING COMMUTE. WINDS REMAIN QUITE BRISK AS 6MB/6HR PRESSURE RISE CENTER OVER NORTHERN LAKE SUPERIOR SLIDES SOUTH AND EAST...WITH 15-25 MPH WINDS THROUGHOUT NORTHERN MICHIGAN...GUSTING AS HIGH AS 35 MPH NEAR THE COASTS. TODAY: WITH THE CORE OF THE H5 LOW PUSHING FROM JUST NORTH OF THE SOO EARLY THIS MORNING TO SOUTHWESTERN QUEBEC BY THSI EVENING...OUR FLOW ALOFT WILL BACK SLIGHTLY AS THE COLDEST AIR ALOFT MAKES ITS CLOSEST APPROACH. T8 AROUND -17C WITH WHAT LOOKS TO BE ROBUST LLEVEL MOISTURE /SEE FOG PRODUCT IMAGERY SHOWING ALL KINDS OF MOISTURE JUST WEST OF THE H5 LOW CENTER /AND THUS...OVERHEAD TODAY/. THIS SPELLS CONTINUED LAKE EFFECT SNOW SHOWERS UNDER STRONG NW WINDS. ALL HIGH RESOLUTION GUIDANCE CONTINUES TO SHOW A DOMINANT BAND TO START THE DAY...WITH THE HRRR LOOKING TO CAPTURE IT/S LOCATION BEST /FURTHER WEST THAN THE RAP AND LOCAL WRF/. GIVEN THAT WE ALREADY HAVE A BAND OF THIS NATURE...SEE NO REASON TO DISAGREE WITH THE GUDIANCE SUGGESTION...WHICH SHOWS THIS BAND STARTING THE DAY CENTERED FROM CVX-ACB-GOV PUSHING EAST GIVEN THE AFOREMENTIONED BACKING FLOW...WITH SOMEWHAT LIGHTER SHSN SURROUNDING IT. THE BAND LOOKS TO BE QUITE MOBILE THROUGH THE MORNING BEFORE CAPE/SHEAR NOMOGRAM SUGGESTS THAT BY LATE MORNING IT WIL BEGIN TO BREAK UP AS OVERLAND INSTABILITY STRENGTHENS. THIS BACKING FLOW SHOULD HELP GET WESTERN CHIPPEWA/MACKINAC BACK INTO THE ACTION DURING THE DAY AS WELL. SNOWFALL: MOBILE SNOWBAND WILL KEEP A LID ON SNOW AMOUNTS...BUT COULD SEE 1-3" FOR THE DAY TODAY OVER THE NW SNOWBELTS...WITH MOST OF THIS FALLING BEFORE ACTIVITY BECOMES MORE CELLULAR THIS AFTERNOON. WHILE WE LOSE HELP FROM ANY ISALLOBARIC COMPONENT TO THE LLEVEL WINDS TODAY...H9 WINDS 25-30KTS AND AMPLE LLEVEL MIXING SUGGEST WINDS 15-25 MPH WINDS WITH GUSTS WELL INTO THE 30S...PARTICULARLY NEAR THE LAKESHORES AND OVER EASTERN UPPER. TEMPS WILL BE VERY SLOW TO CLIMB WITH T9 AROUND -10C SUGGESTING MID 20S /SOME 20F BELOW NORMAL/ WILL BE ABOUT ALL WE CAN MUSTER. WITH THE STRONG WINDS...WIND CHILLS WILL REMAIN IN THE TEENS THROUGH THE DAY. HEADLINES: WILL GO AHEAD AND DROP WINTER WEATHER ADVISORY FOR CHIPPEWA GIVEN LOCATION OF SNOWFALL ACTIVITY WELL WEST OF COUNTY WITH ACCUMS THUS FAR NOT SUFFICIENT TO WARRANT THE HEADLINE. AS DISCUSSED ABOVE...HEAVIEST SNOW IS NOW OVER THE BIG 5 IN NW LOWER...AND WILL MONITOR FOR POTENTIAL HEADLINE THROUGH DAYBREAK...ALTHOUGH EXPECTATION IS THAT THE BAND WILL BEGIN TO MOVE...REDUCING THE THREAT OF SIGNIFICANT ACCUMS. TONIGHT: SYNOPTIC MOISTURE BEGINS TO SLOWLY ERODE WITH TEMPS ALOFT STEADY OR JUST SLIGHTLY WARING UNDER A FAIRLY STEADY 300-310 FLOW REGIME. SOME RESIDUAL LAND-BASED CAPE CONTINUES THROUGH THE OVERNIGHT WHICH MAY NOT FULLY ALLOW THE LAKE EFFECT TO RE-SOLIDIFY INTO BANDS. SHSN WILL CERTAINLY CONTINUE...HOWEVER...WITH ADDITIONAL LIGHT ACCUMULATIONS LIKELY. INHERITED ACCUMS OF 1-2 INCHES /PERHAPS 3 OVER WESTERN CHIPPEWA/ LOOK REASONABLE AND HAVE NO COMPELLING REASON TO DEVIATE SIGNIFICANTLY. CLOUDS WILL LIKELY KEEP TEMPERATURES FROM FALLING ALL THAT FAR... GENERALLY IN THE UPPER TEENS TO AROUND 20. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 422 AM EDT MON APR 1 2013 TUESDAY...AS THE SFC HIGH BEGINS TO MOVE INTO THE REGION, THE 850 MB TEMPERATURES BEGIN TO WARM SLIGHTLY, JUST ENOUGH THAT WE MAY LOSE THE INSTABILITY NEEDED FOR THE LES. THE MOISTURE IN THE 850-700 MB LAYER FALLS OFF TO BELOW 60% ON ALL THE MODELS SO WOULD EXPECT LIGHT SNOW AND FLURRIES. ALTHOUGH WILL HAVE LIKELY POPS SINCE MEASURABLE SNOW IS EXPECTED FROM THIS PATTERN IN THE MORNING. BY THE AFTERNOON, THE MOISTURE CONTINUES TO FALL OFF IN THE 850-700 MB LAYER. THE ONE THING THAT I HAVE NOTICED ABOUT THESE LATE SEASON LES EVENTS IS THAT IT HAS BECOME HARD FOR THE LOWER END OF THE SOUNDINGS TO SATURATE. THIS HAS BEEN LEADING TO INVERTED V SOUNDINGS AND REALIZING LESS SNOW THAN WE WOULD HAVE EVEN A MONTH AGO DURING THE AFTERNOON. TUESDAY NIGHT...AS THE RIDGE BUILDS INTO THE REGION, THE DRIER AIR REALLY BEGINS TO OVERWHELM THE REGION, SHUTTING OFF MOST OF THE SNOW LEAVING ONLY CHANCE POPS IN THE EVENING IN E UPPER, WHILE N LOWER WILL BE DRY ENOUGH TO NOT HAVE ANY SNOW. WEDNESDAY...HIGH PRESSURE AT THE SFC AND 500 MB RIDGE MOVES THROUGH THE REGION SO THAT WE WILL REMAIN DRY FOR THE DAY. OVERNIGHT, A COLD FRONT AND 500 MB SHORTWAVE TROUGH MOVE INTO THE REGION. THE GFS IS A LITTLE FASTER THAN THE ECMWF AND NAM. WILL HOLD OFF THE SNOW BY ALLOWING IT TO JUST TOUCH E UPPER BY 12Z. EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, THE MODELS DRY THINGS OUT WITH THE FRONTAL PASSAGE DURING THE DAY. SO WILL HAVE CHANCE POPS WITH A MIX OF THE RAIN AND SNOW IN E UPPER AND JUST RAIN IN N LOWER. WITH THE SFC TEMPERATURES IN THE 40S, WOULD NOT BE SURPRISED IF THIS TURNS OUT TO BE FLURRIES AND SPRINKLES. FRIDAY, THE HIGH BUILDS INTO THE UPPER GREAT LAKES REGION AND DRIES THINGS OUT AGAIN. SO DRY WEATHER WILL BE EXPECTED. SATURDAY, THE WARM FRONT WILL BE MOVING INTO THE REGION. THE ECMWF HAS THE WARM AIR INTO E UPPER SO THAT IT COULD BE ALL RAIN, WHILE THE GFS HAS IT PLACED A LITTLE SOUTH. PUT THE DIVIDING LINE AT THE STRAITS SINCE THAT SEEMED TO BE THE MIDDLE GROUND. WHICH WOULD CONTINUE THROUGH THE NIGHT AS THE SYSTEM MOVES EAST. SUNDAY, THE LOW MOVES EAST OF THE REGION AND THE COLD AIR MOVES BACK IN ALLOWING FOR A CHANGE OVER TO SNOW. THE GFS DRIES THINGS OUT. WILL LEAN TOWARD THE ECMWF WHICH WOULD BE THE PESSIMISTIC FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 128 AM EDT MON APR 1 2013 SUMMARY: STRONG NORTHWEST FLOW WILL CONTINUE THROUGH THE UPCOMING TAF PERIOD...WITH LAKE EFFECT SNOW SHOWERS OCCASIONALLY IMPACTING THE TERMINALS. RESTRICTIONS: EXPECT VFR CONDITIONS TO DOMINATE MOST OF THE TAF PERIOD...WITH HEAVIEST LES OVERNIGHT TONIGHT REMAINING BETWEEN PLN AND TVC. BANDING LOOKS TO TARGET PLN SOMETIME LATER THIS MORNING/EARLY AFTERNOON...ALTHOUGH IT WILL LIKELY BE BREAKING UP INTO MORE CELLULAR ACTIVITY BY THIS TIME. SO...WILL ONLY INCLUDE A PERIOD OF MVFR WITH THIS TAF PACKAGE...AND AWAIT LATER TRENDS TO POTENTIALLY ADD A SHORT PERIOD OF IFR. AT THE OTHER TERMINALS...WHILE A QUICK DROP TO MVFR IN SHSN IS POSSIBLE...THERE IS LOW CONFIDENCE IN TIMING...SO WILL FOLLOW TRENDS THROUGH THE REMAINDER OF THE OVERNIGHT BEFORE ADDING ANY TEMPOS AT TVC/APN. AT THIS TIME...MBL LOOKS TO REMAIN VFR. WINDS: NORTHWEST WINDS 14G22KTS TONIGHT WILL CONTINUE 18G28KTS FOR THE DAY ON MONDAY BEFORE DIMINISHING TO 10-15KTS MONDAY NIGHT. && .MARINE... ISSUED AT 422 AM EDT MON APR 1 2013 SUMMARY: STRONG NORTHWESTERLY WINDS TO CONTINUE THROUGH TUESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. HIGH PRESSURE ARRIVES BY MIDWEEK WITH QUIETER CONDITIONS EXPECTED. HEADLINES: MARGINAL GALES WILL BE ALLOWED TO CONTINUE ALL ZONES THROUGH THIS EVENING. SMALL CRAFTS WILL CERTAINLY BE NEEDED BEYOND THIS...WITH ADDITIONAL GALE FORCE GUSTS POSSIBLE AGAIN TUESDAY...PARTICULARLY FOR NORTHWESTERLY FLOW FAVORED REGIONS. BEYOND THIS...NEXT ROUND OF SMALL CRAFTS LOOKS LIKELY BY WEDNESDAY NIGHT OVER LAKE MICHIGAN AS SOUTHWESTERLY WINDS STRENGTHEN AHEAD OF NEXT APPROACHING SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...WINTER WEATHER ADVISORY UNTIL NOON EDT TODAY FOR MIZ019-021-022- 028. LH...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LHZ345>349. LM...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LMZ323-341-342- 344>346. LS...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ321-322. && $$ UPDATE...ARNOTT SYNOPSIS...JL SHORT TERM...ARNOTT LONG TERM...JL AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
444 AM EDT MON APR 1 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 440 AM EDT MON APR 1 2013 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP UPR TROF CENTERED FM HUDSON BAY INTO THE GRT LKS DOWNSTREAM OF UPR RDG OVER WRN CANADA. 00Z H5/H85 TEMPS ARE AS LO AS -42C/-20C AT THE CORE OF THE COLDEST AIR AT YPL. CYC NNW FLOW ON THE WRN FLANK OF LO PRES MOVING SLOWLY E INTO QUEBEC IS DRAWING THIS VERY COLD AIR SWD INTO THE UPR LKS OVER THE RELATIVELY WARM WATERS OF LAKE SUP...WITH THE RESULT NMRS LES BANDS AS SHOWN ON MQT RADAR. WELL DEFINED AXIS OF COLDER CLD TOPS AS SHOWN ON IR STLT IMAGERY IS PRESENT OVER THE E HALF OF THE LK AND ASSOCIATED WITH FAIRLY SHARP H7-3 QVECTOR CNVGC. THIS AXIS OF DEEPER MSTR HAS CAUSED SOME ENHANCEMENT TO THE SHSN. THE HEAVIEST BAND IS STREAMING INTO CENTRAL ALGER COUNTY/SCHOOLCRAFT COUTY...WITH SOME RETURNS AOA 30 DBZ AT 06Z. SN UNDER THIS BAND IS LIKELY FALLING AT THE RATE OF AT LEAST AN INCH/HR GIVEN FAVORABLE LOCATION OF UVV MAX WITHIN DGZ AS SHOWN BY PROFILE FM LOCAL HI RES MODEL. SINCE THE COLDER CLD TOPS ARE TENDING TO DRIFT TO THE E AND DRIER LLVL AIR SHOWN ON THE 00Z INL RAOB IS PRESSING TO THE E... DROPPING THE SFC DEWPT TO NEAR 7F AT IWD AT 06Z...THE INTENSITY OF THE LES W OF MQT HAS TENDED TO DIMINISH OVER TIME PER RADAR TRENDS EVEN THOUGH IR STLT IMAGERY INDICATES SOME LES BANDS OVER THE W HALF OF THE LK THAT HAVE FORMED IN THE PRESENCE OF NOCTURNAL COOLING THAT IS SO IMPORTANT TO ACHIEVE BETTER LES BAND STRUCTURE THIS TIME OF YEAR. NW WINDS ARE STILL GUSTING AS HI AS 40 KTS AT STANNARD ROCK AS OF 06Z...BUT PASSAGE OF PRES RISE CENTER TRAILING THE SFC LO INTO ONTARIO E OF LK SUP HAS CAUSED A SLOW DIMINISHING TREND TO THE WINDS. MAIN FCST CONCERNS THIS PACKAGE ARE LES TRENDS/GOIND HEADLINES. TODAY...MODELS INDICATE UPR TROF AXIS WL DRIFT SLOWLY TO THE E. AREA OF DEEP LYR QVECTOR CNVGC ENHANCING COMMA HEAD/COLDER CLD TOPS NOW OVER THE E HALF OF LK SUP IS PROGGED TO DRIFT INTO ONTARIO IN THE 09Z-12Z TIME FRAME. IN CONCERT WITH THE ARRIVAL OF SOME DRYING FM THE W...LES INTENSITY/COVERAGE SHUD DIMINISH BY SUNRISE. BUT GIVEN PERSISTENCE OF SGNFT BAND OVER CENTRAL ALGER COUNTY INTO NRN SCHOOLCRAFT COUNTY IN PERSISTENT NNW FLOW THRU THE EARLY MRNG HRS...FVRBL SN/WATER RATIOS UNDER COLDEST H85 TEMPS...AND HIER RES MODEL FCSTS THAT SHOWING FAIRLY HI QPF THRU 18Z WITH DEEPER MSTR PERSISTING LONGEST IN THAT AREA CLOSER TO DEPARTING LO...OPTED TO UPGRADE GOING ADVY FOR THOSE ZONES TO AN LES WARNING. OTRW...RISING H5 HGTS/DEEP LYR QVECTOR CNVGC/SUBSIDENCE IN THE PRESENCE OF DIURNAL HEATING THAT TENDS TO DISRUPT THE LES PROCESS IN EARLY SPRING SHOULD CAUSE THE LES BANDS TO WEAKEN AND TRANSITION TO A MORE BLOTCHY APPEARANCE. SLOWLY BACKING FLOW TOWARD MORE WNW BY THE LATE IN THE DAY WL ALSO CAUSE AREA OF HEAVIER SHSN TO SHIFT. ADDITIONAL SN AMOUNTS OVER THE W WL BE LIGHT WITH LLVL DRY AIR HAVING A MORE SGNFT IMPACT THERE AND MODELS HINTING TOWARD A TRANSITION TO LLVL ACYC FLOW IN THE AFTN. TONIGHT...STEADILY RISING HGTS/DEEP LYR QVECTOR CNVGC THAT DROPS FCST INVRN BASE TOWARD 5-6K FT OVER EVEN THE E SUG LES INTENSITY WL BE SOMEWHAT DIMINISHED EVEN THOUGH PERSISTENT NW FLOW/H85 TEMPS IN THE -16 TO -17C RANGE WL ALLOW FOR CONTINUED WDSPRD LES...ESPECIALLY AFTER MID EVNG WHEN IMPACTS OF DAYTIME HEATING WOULD TEND TO SUBSIDE. WITH INVRN BASE OVER THE W FALLING TO ARND 4K FT OVER THE W...SHSN INTENSITY IN THIS AREA WL BE WEAKER WITH SHORTER FETCH/LESS MODERATION OF UPSTREAM AIRMASS. BUT STILL WENT WITH LIKELY POPS GIVEN FVRBL NW FLOW/OVERWATER INSTABILITY/NOCTURNAL COOLING THAT WL ALLOW LES BANDS TO REDEVELOP. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 440 AM EDT MON APR 1 2013 DESPITE ADEQUATE DELTA TS PERSISTING INTO TUESDAY FOR LAKE EFFECT...SFC-H85 FLOW WILL BECOME INCREASINGLY ANTICYCLONIC THROUGH THE DAY. IN ADDITION...INVERSION HEIGHTS BEGIN TO FALL OFF SIGNIFICANTLY BELOW 5KFT. THUS...EXPECT OVERALL COVERAGE AND INTENSITY OF LAKE EFFECT TO BE ON THE WANE AS THE DAY PROGRESSES. TEMPERATURES WILL REMAIN WELL BELOW NORMAL WITH A SIGNIFICANT AMOUNT OF CLOUDINESS DOWNWIND OF LAKE SUPERIOR. LAKE CLOUDS AND EVEN A FEW FLURRIES WILL PERSIST INTO THE MORNING WEDNESDAY OVER THE EAST. AS SURFACE RIDGE AXIS MOVES OVERHEAD THROUGH THE DAY EXPECT SKIES TO BECOME MOSTLY SUNNY AREA WIDE. TEMPERATURES SHOULD REBOUND BACK ABOVE FREEZING AND EVEN APPROACH 40 ACROSS THE WEST WITH WARM ADVECTION INCREASING DURING THE AFTERNOON AND MORE SUNSHINE. MODELS COMING INTO BETTER AGREEMENT WITH THE TIMING OF THE NEXT SHORTWAVE AND SFC TROUGH EXPECTED TO MOVE ACROSS THE AREA WED NIGHT/THU. THE TREND HAS BEEN TOWARD QUICKER MOVEMENT WITH THE TROUGH. SYSTEM IS FAIRLY MOISTURE STARVED...SO DESPITE PRECIP TYPE BEING A CHALLENGE BETWEEN RAIN AND SNOW...AMOUNTS WILL BE LIGHT ENOUGH TO BE PRETTY INSIGNIFICANT. COLD ADVECTION BEHIND THE TROUGH SHOULD PUSH 85H TEMPS BACK DOWN TO THE -10 TO -14C RANGE BY FRIDAY. PROBABLY NOT QUITE COLD ENOUGH FOR LAKE EFFECT THIS TIME AROUND...BUT COLDER AIR WILL KEEP DAYTIME TEMPS BELOW AVERAGE ONLY IN THE 30S. FORECAST FOR NEXT WEEKEND STILL PRETTY CHALLENGING...BUT MODELS SHOWING SOME SIGNS THAT THEY ARE TRYING TO CONVERGE ON A MORE PROBABLE OUTCOME. SHORTWAVE ENERGY AND ASSOCIATED SURFACE LOW MOVING OUT OF THE PLAINS LOOKING LIKE THEY MAY NOW TRACK THROUGH THE LOWER LAKES WHICH WOULD STILL RESULT IN SOME LIGHT SNOWFALL ACROSS SOUTHERN AREAS SATURDAY INTO SUNDAY BUT SPARE THE AREA FROM A MORE SIGNIFICANT STORM. IT IS STILL SOMETHING TO KEEP AN EYE ON AS WE HEAD THROUGH THE WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 129 AM EDT MON APR 1 2013 INCREASINGLY COLDER AIR MOVING ACROSS LAKE SUPERIOR IN NW FLOW WILL SUSTAIN PERIODS OF LAKE EFFECT SNOW SHOWERS AND MVFR CONDITIONS INTO MONDAY AT ALL 3 TAF SITES. GUSTY NW WINDS TO 25 KTS AT TIMES COULD ALSO CONTRIBUTE TO LOWER IFR VSBYS IN SNOW AND BLOWING SNOW...MAINLY AT MORE EXPOSED KCMX SITE. WINDS BACKING A BIT MORE TO THE WNW...SHOULD REDUCE CHCS FOR LAKE EFFECT SNOW SHOWERS AT KSAW BY MONDAY AFTERNOON...PERHAPS EVEN LEADING TO VFR CONDITIONS BY MONDAY EVENING. ARRIVAL OF DRIER NEAR SFC AIR SHOWN ON THE 00Z INL RAOB WILL ALSO BRING ABOUT LONG PERIODS OF VFR CONDITIONS AT IWD. THE COMBINATION OF THE DRYING AND DAYTIME HEATING THIS AFTN WILL DIMINISH THE LES INTENSITY AT CMX AS WELL. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 440 AM EDT MON APR 1 2013 AS LO PRES OVER SE CANADA CONTINUES TO THE E AND THE PRES GRADIENT WEAKENS...EXPECT NW WINDS TO SLOWLY DIMINISH AND BELOW GALE FORCE OVER THE CENTRAL BY MID MORNING...SO HASTENED THE ENDING OF THE GALE WARNINGS FOR THIS AREA. ALTHOUG NW GALES TO 35 KTS WILL CONTINUE LONGER OVER THE E INTO THIS EVENING...ENDED THE GALES FOR THAT AREA EARLIER AS WELL. WINDS/WAVES WILL BE SUFFICIENT TO MAINTAIN FREEZING SPRAY OVER AT LEAST THE E HALF THRU TONIGHT. WINDS WILL REMAIN PRETTY GUSTY UP TO 30 KNOTS OVER THE EASTERN LAKE THROUGH THE DAY ON TUESDAY...BUT AS SURFACE RIDGE AXIS PUSHES IN FROM THE WEST PRESSURE GRADIENT WILL RELAX AND WINDS WILL DIMINISH DURING THE EVENING. UNTIL THAT TIME...FREEZING SPRAY SHOULD CONTINUE ACROSS THE EASTERN LAKE. AFTER A BRIEF RESPITE ON WEDNESDAY...SOUTHWESTERLY WINDS UP TO 25 KNOTS AHEAD OF THE NEXT TROUGH CROSSING THE LAKE WILL INCREASE WEDNESDAY NIGHT INTO EARLY THURSDAY BEFORE SHIFTING TO THE NORTHWEST DURING THE DAY THURSDAY INTO THURSDAY NIGHT. WINDS FOR FRIDAY INTO NEXT WEEKEND SHOULD BE BELOW 20 KNOTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007. LAKE EFFECT SNOW WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006-085. LAKE SUPERIOR... GALE WARNING UNTIL 2 AM EDT TUESDAY FOR LSZ266-267. GALE WARNING UNTIL NOON EDT TODAY FOR LSZ265. GALE WARNING UNTIL 8 AM EDT THIS MORNING FOR LSZ264. GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249. GALE WARNING UNTIL 6 PM EDT THIS EVENING FOR LSZ244-245. GALE WARNING UNTIL 6 AM EDT TUESDAY FOR LSZ250-251. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MZ AVIATION...VOSS/KC MARINE...KC/MZ
AREA FORECAST DISCUSSION
NWS GAYLORD MI
430 AM EDT MON APR 1 2013 .SYNOPSIS... ISSUED AT 422 AM EDT MON APR 1 2013 A SYSTEM IN QUEBEC IS BRINGING COLD AIR AND NORTHWEST WINDS TO THE STATE TODAY. THE COLDER AIR IS PRODUCING LAKE EFFECT SNOW SHOWERS WHICH WILL PERSIST OVER NORTHERN MICHIGAN THROUGH TUESDAY. THE MOST PERSISTENT SNOW SHOWERS WITH THE BEST CHANCE OF ACCUMULATION WILL BE IN THE TYPICAL SNOW BELTS OF NORTHWEST LOWER AND EAST UPPER MICHIGAN. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 422 AM EDT MON APR 1 2013 HIGH IMPACT WEATHER POTENTIAL: GALE FORCE WIND GUSTS POSSIBLE ALL MARINE WATERS THROUGH TODAY. SNOW/BLOWING SNOW WILL BRING SOME SLICK TRAVEL AND REDUCED VISIBILITIES TO THE SNOWBELTS OF EASTERN UPPER/NORTHERN LOWER...WITH SNOW SHOWERS REACHING ALL OTHER LOCALES AS WELL. OVERVIEW: WISHING THE EARLY MORNING WATER VAPOR IMAGERY WAS AN APRIL FOOLS JOKE THIS MORNING AS IMPRESSIVE TROUGH CARVES ITSELF OUT OVER THE GREAT LAKES REGION. PICKLE LAKE /ONTARIO/ 00Z RAOB SHOWS -42C AT H5...-25C AT H7 AND -20C AT H8...AN ARCTIC AIRMASS INDEED WITH SURFACE TEMPS UPSTREAM OF THE GREAT LAKES IN THE LOWER TEENS AND DEWPOINTS FALLING TO NEAR ZERO. WITH SUBSTANTIAL DOWNSTREAM BLOCKING IN PLACE FROM GREENLAND SOUTH AND EAST...THE DEVELOPING LONGWAVE TROUGH OVERHEAD WILL BE IN NO HURRY TO DEPART...WITH ITS IMPACTS DOMINATING THE SHORT TERM PORTION OF THE FORECAST. THROUGH DAYBREAK: APX WSR-88D SHOWING LAKE EFFECT SNOW GETTING IT/S ACT TOGETHER OVER NORTHERN LOWER...WITH PRIMARY BAND FROM ACB-GOV STRENGTHENING WITH GOOD LAKE SUPERIOR CONNECTION. EXPECT THIS TREND TO CONTINUE THROUGH DAYBREAK WITH AN INCH OR TWO OF SNOW POSSIBLE OVER THE BIG 5 OF NW LOWER. WILL COVER THIS BAND WITH AN SPS FOR A QUICK 1-2 INCHES WHICH WILL LIKELY IMPACT THE MONDAY MORNING COMMUTE. WINDS REMAIN QUITE BRISK AS 6MB/6HR PRESSURE RISE CENTER OVER NORTHERN LAKE SUPERIOR SLIDES SOUTH AND EAST...WITH 15-25 MPH WINDS THROUGHOUT NORTHERN MICHIGAN...GUSTING AS HIGH AS 35 MPH NEAR THE COASTS. TODAY: WITH THE CORE OF THE H5 LOW PUSHING FROM JUST NORTH OF THE SOO EARLY THIS MORNING TO SOUTHWESTERN QUEBEC BY THSI EVENING...OUR FLOW ALOFT WILL BACK SLIGHTLY AS THE COLDEST AIR ALOFT MAKES ITS CLOSEST APPROACH. T8 AROUND -17C WITH WHAT LOOKS TO BE ROBUST LLEVEL MOISTURE /SEE FOG PRODUCT IMAGERY SHOWING ALL KINDS OF MOISTURE JUST WEST OF THE H5 LOW CENTER /AND THUS...OVERHEAD TODAY/. THIS SPELLS CONTINUED LAKE EFFECT SNOW SHOWERS UNDER STRONG NW WINDS. ALL HIGH RESOLUTION GUIDANCE CONTINUES TO SHOW A DOMINANT BAND TO START THE DAY...WITH THE HRRR LOOKING TO CAPTURE IT/S LOCATION BEST /FURTHER WEST THAN THE RAP AND LOCAL WRF/. GIVEN THAT WE ALREADY HAVE A BAND OF THIS NATURE...SEE NO REASON TO DISAGREE WITH THE GUDIANCE SUGGESTION...WHICH SHOWS THIS BAND STARTING THE DAY CENTERED FROM CVX-ACB-GOV PUSHING EAST GIVEN THE AFOREMENTIONED BACKING FLOW...WITH SOMEWHAT LIGHTER SHSN SURROUNDING IT. THE BAND LOOKS TO BE QUITE MOBILE THROUGH THE MORNING BEFORE CAPE/SHEAR NOMOGRAM SUGGESTS THAT BY LATE MORNING IT WIL BEGIN TO BREAK UP AS OVERLAND INSTABILITY STRENGTHENS. THIS BACKING FLOW SHOULD HELP GET WESTERN CHIPPEWA/MACKINAC BACK INTO THE ACTION DURING THE DAY AS WELL. SNOWFALL: MOBILE SNOWBAND WILL KEEP A LID ON SNOW AMOUNTS...BUT COULD SEE 1-3" FOR THE DAY TODAY OVER THE NW SNOWBELTS...WITH MOST OF THIS FALLING BEFORE ACTIVITY BECOMES MORE CELLULAR THIS AFTERNOON. WHILE WE LOSE HELP FROM ANY ISALLOBARIC COMPONENT TO THE LLEVEL WINDS TODAY...H9 WINDS 25-30KTS AND AMPLE LLEVEL MIXING SUGGEST WINDS 15-25 MPH WINDS WITH GUSTS WELL INTO THE 30S...PARTICULARLY NEAR THE LAKESHORES AND OVER EASTERN UPPER. TEMPS WILL BE VERY SLOW TO CLIMB WITH T9 AROUND -10C SUGGESTING MID 20S /SOME 20F BELOW NORMAL/ WILL BE ABOUT ALL WE CAN MUSTER. WITH THE STRONG WINDS...WIND CHILLS WILL REMAIN IN THE TEENS THROUGH THE DAY. HEADLINES: WILL GO AHEAD AND DROP WINTER WEATHER ADVISORY FOR CHIPPEWA GIVEN LOCATION OF SNOWFALL ACTIVITY WELL WEST OF COUNTY WITH ACCUMS THUS FAR NOT SUFFICIENT TO WARRANT THE HEADLINE. AS DISCUSSED ABOVE...HEAVIEST SNOW IS NOW OVER THE BIG 5 IN NW LOWER...AND WILL MONITOR FOR POTENTIAL HEADLINE THROUGH DAYBREAK...ALTHOUGH EXPECTATION IS THAT THE BAND WILL BEGIN TO MOVE...REDUCING THE THREAT OF SIGNIFICANT ACCUMS. TONIGHT: SYNOPTIC MOISTURE BEGINS TO SLOWLY ERODE WITH TEMPS ALOFT STEADY OR JUST SLIGHTLY WARING UNDER A FAIRLY STEADY 300-310 FLOW REGIME. SOME RESIDUAL LAND-BASED CAPE CONTINUES THROUGH THE OVERNIGHT WHICH MAY NOT FULLY ALLOW THE LAKE EFFECT TO RE-SOLIDIFY INTO BANDS. SHSN WILL CERTAINLY CONTINUE...HOWEVER...WITH ADDITIONAL LIGHT ACCUMULATIONS LIKELY. INHERITED ACCUMS OF 1-2 INCHES /PERHAPS 3 OVER WESTERN CHIPPEWA/ LOOK REASONABLE AND HAVE NO COMPELLING REASON TO DEVIATE SIGNIFICANTLY. CLOUDS WILL LIKELY KEEP TEMPERATURES FROM FALLING ALL THAT FAR... GENERALLY IN THE UPPER TEENS TO AROUND 20. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 422 AM EDT MON APR 1 2013 TUESDAY...AS THE SFC HIGH BEGINS TO MOVE INTO THE REGION, THE 850 MB TEMPERATURES BEGIN TO WARM SLIGHTLY, JUST ENOUGH THAT WE MAY LOSE THE INSTABILITY NEEDED FOR THE LES. THE MOISTURE IN THE 850-700 MB LAYER FALLS OFF TO BELOW 60% ON ALL THE MODELS SO WOULD EXPECT LIGHT SNOW AND FLURRIES. ALTHOUGH WILL HAVE LIKELY POPS SINCE MEASURABLE SNOW IS EXPECTED FROM THIS PATTERN IN THE MORNING. BY THE AFTERNOON, THE MOISTURE CONTINUES TO FALL OFF IN THE 850-700 MB LAYER. THE ONE THING THAT I HAVE NOTICED ABOUT THESE LATE SEASON LES EVENTS IS THAT IT HAS BECOME HARD FOR THE LOWER END OF THE SOUNDINGS TO SATURATE. THIS HAS BEEN LEADING TO INVERTED V SOUNDINGS AND REALIZING LESS SNOW THAN WE WOULD HAVE EVEN A MONTH AGO DURING THE AFTERNOON. TUESDAY NIGHT...AS THE RIDGE BUILDS INTO THE REGION, THE DRIER AIR REALLY BEGINS TO OVERWHELM THE REGION, SHUTTING OFF MOST OF THE SNOW LEAVING ONLY CHANCE POPS IN THE EVENING IN E UPPER, WHILE N LOWER WILL BE DRY ENOUGH TO NOT HAVE ANY SNOW. WEDNESDAY...HIGH PRESSURE AT THE SFC AND 500 MB RIDGE MOVES THROUGH THE REGION SO THAT WE WILL REMAIN DRY FOR THE DAY. OVERNIGHT, A COLD FRONT AND 500 MB SHORTWAVE TROUGH MOVE INTO THE REGION. THE GFS IS A LITTLE FASTER THAN THE ECMWF AND NAM. WILL HOLD OFF THE SNOW BY ALLOWING IT TO JUST TOUCH E UPPER BY 12Z. EXTENDED (THURSDAY THROUGH SUNDAY)...THURSDAY, THE MODELS DRY THINGS OUT WITH THE FRONTAL PASSAGE DURING THE DAY. SO WILL HAVE CHANCE POPS WITH A MIX OF THE RAIN AND SNOW IN E UPPER AND JUST RAIN IN N LOWER. WITH THE SFC TEMPERATURES IN THE 40S, WOULD NOT BE SURPRISED IF THIS TURNS OUT TO BE FLURRIES AND SPRINKLES. FRIDAY, THE HIGH BUILDS INTO THE UPPER GREAT LAKES REGION AND DRIES THINGS OUT AGAIN. SO DRY WEATHER WILL BE EXPECTED. SATURDAY, THE WARM FRONT WILL BE MOVING INTO THE REGION. THE ECMWF HAS THE WARM AIR INTO E UPPER SO THAT IT COULD BE ALL RAIN, WHILE THE GFS HAS IT PLACED A LITTLE SOUTH. PUT THE DIVIDING LINE AT THE STRAITS SINCE THAT SEEMED TO BE THE MIDDLE GROUND. WHICH WOULD CONTINUE THROUGH THE NIGHT AS THE SYSTEM MOVES EAST. SUNDAY, THE LOW MOVES EAST OF THE REGION AND THE COLD AIR MOVES BACK IN ALLOWING FOR A CHANGE OVER TO SNOW. THE GFS DRIES THINGS OUT. WILL LEAN TOWARD THE ECMWF WHICH WOULD BE THE PESSIMISTIC FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 128 AM EDT MON APR 1 2013 SUMMARY: STRONG NORTHWEST FLOW WILL CONTINUE THROUGH THE UPCOMING TAF PERIOD...WITH LAKE EFFECT SNOW SHOWERS OCCASIONALLY IMPACTING THE TERMINALS. RESTRICTIONS: EXPECT VFR CONDITIONS TO DOMINATE MOST OF THE TAF PERIOD...WITH HEAVIEST LES OVERNIGHT TONIGHT REMAINING BETWEEN PLN AND TVC. BANDING LOOKS TO TARGET PLN SOMETIME LATER THIS MORNING/EARLY AFTERNOON...ALTHOUGH IT WILL LIKELY BE BREAKING UP INTO MORE CELLULAR ACTIVITY BY THIS TIME. SO...WILL ONLY INCLUDE A PERIOD OF MVFR WITH THIS TAF PACKAGE...AND AWAIT LATER TRENDS TO POTENTIALLY ADD A SHORT PERIOD OF IFR. AT THE OTHER TERMINALS...WHILE A QUICK DROP TO MVFR IN SHSN IS POSSIBLE...THERE IS LOW CONFIDENCE IN TIMING...SO WILL FOLLOW TRENDS THROUGH THE REMAINDER OF THE OVERNIGHT BEFORE ADDING ANY TEMPOS AT TVC/APN. AT THIS TIME...MBL LOOKS TO REMAIN VFR. WINDS: NORTHWEST WINDS 14G22KTS TONIGHT WILL CONTINUE 18G28KTS FOR THE DAY ON MONDAY BEFORE DIMINISHING TO 10-15KTS MONDAY NIGHT. && .MARINE... ISSUED AT 422 AM EDT MON APR 1 2013 SUMMARY: STRONG NORTHWESTERLY WINDS TO CONTINUE THROUGH TUESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. HIGH PRESSURE ARRIVES BY MIDWEEK WITH QUIETER CONDITIONS EXPECTED. HEADLINES: MARGINAL GALES WILL BE ALLOWED TO CONTINUE ALL ZONES THROUGH THIS EVENING. SMALL CRAFTS WILL CERTAINLY BE NEEDED BEYOND THIS...WITH ADDITIONAL GALE FORCE GUSTS POSSIBLE AGAIN TUESDAY...PARTICULARLY FOR NORTHWESTERLY FLOW FAVORED REGIONS. BEYOND THIS...NEXT ROUND OF SMALL CRAFTS LOOKS LIKELY BY WEDNESDAY NIGHT OVER LAKE MICHIGAN AS SOUTHWESTERLY WINDS STRENGTHEN AHEAD OF NEXT APPROACHING SYSTEM. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LHZ345>349. LM...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LMZ323-341-342- 344>346. LS...GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LSZ321-322. && $$ SYNOPSIS...JL SHORT TERM...ARNOTT LONG TERM...JL AVIATION...ARNOTT MARINE...ARNOTT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
235 AM EDT MON APR 1 2013 .UPDATE... ISSUED AT 233 AM EDT MON APR 1 2013 OPTED TO UPGRADE ADVY FOR ALGER/NRN SCHOOLCRAFT TO A WARNING GIVEN PERSISTENCE OF INTENSE LES BAND JUST E OF MUNISING UNDER COLDER CLD TOPS ASSOCIATED WITH DEEPENING UPR TROF...FVRBL SN/WATER RATIOS WITH UVV MAX WITHIN DGZ...AND REPORTS OF SGNFT BLSN/WHITEOUT CONDITIONS ALONG M-28. ALTHOUGH THE EXPECTED DEPARTURE OF THE COLDER CLD TOPS BY 09Z WOULD SUG THE BAND WL DIMINISH...PERSISTENCE OF BAND SINCE MID EVNG ARND 03Z AND ESTIMATED SN ACCUMS UP TO 2 INCHES/HR SINCE BAND DVLPD SUG WARNING AMNTS ARE LIKELY FM SHINGLETON AND MELSTRAND TO GRAND MARAIS AND SENEY. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 451 PM EDT SUN MAR 31 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF DEEPENING INTO THE GREAT LAKES REGION. VIGOROUS SHORTWAVE WAS PASSING OVER LAKE SUPERIOR. PER SATELLITE IMAGERY AND CANADIAN RADAR IMAGERY...AN ASSOCIATED IMPRESSIVE LOOKING SMALL SWATH OF MDT TO HVY SNOW HAS PASSED JUST N OF THE FCST AREA ACROSS FAR NRN LAKE SUPERIOR/ADJACENT ONTARIO TODAY...ALONG/JUST N OF SHORTWAVE TRACK. AN INCREASINGLY WELL-DEFINED SFC LOW PRES IS ORGANIZING OVER EASTERN LAKE ATTM PER VIS SATELLITE IMAGERY. TO THE S...-SHSN TODAY HAVE DEFINITELY TAKEN ON A SPRINGTIME DIURNAL LAND BASED LOOK WITH UNORGANIZED SCT/NMRS COVERAGE. WELL-MIXED LAYER HAS PREVENTED SOME OF THE PCPN FROM REACHING THE GROUND. UPSTREAM 12Z KINL SOUNDING SHOWED A DEEP MOISTURE PROFILE TO 650MB (AROUND 11KFT)... AND MODIFYING SOUNDING FOR A SFC T/TD IN THE LWR 30S/LWR 20S YIELDED SBCAPE AROUND 100J/KG...AND THUS THE DIURNAL COMPONENT TO THE -SHSN THIS AFTN. MAIN FCST ISSUES TONIGHT/MON ARE POTENTIAL LES ACCUMULATIONS AS WELL AS WINDS. FIRST UP...WINDS. EXPECT STRONGEST WINDS TO OCCUR FROM NOW THRU THE ABOUT MID EVENING AS AREA OF 4MB/3HR PRES RISES CURRENTLY JUST NW OF LAKE SUPERIOR SETTLES SE. THE DEEPENING INCREASINGLY WELL-DEFINED SFC LOW OVER ERN LAKE SUPERIOR IS A CONCERN AS IT WILL SERVE TO STRENGTHEN ISALLOBARIC WINDS. SOME OF THE HIGHER RES MODEL GUIDANCE SEEMS TO BE PICKING UP ON THIS AS A SMALL 5-6MB/3HR PRES RISE MAX DEVELOPS OVER CNTRL/ERN LAKE SUPERIOR WITHIN THE LARGER SCALE PRES RISES. THE IMPACT OF THE DEEPENING LOW HAS ALREADY MADE AN IMPACT AS WINDS HAVE GUSTED TO 50MPH AT KP59. THIS SHOULD BE A GOOD INDICATION OF WHAT IS TO COME IN THE NEXT FEW HRS TO THE E OF MARQUETTE. WIND ADVY HAS BEEN ISSUED FOR KEWEENAW COUNTY INTO MID EVENING TO ACCOUNT FOR STRONG WINDS OVER THE NEXT FEW HRS. AS FOR SNOW...NNW CYCLONIC FLOW SHOULD ALLOW SOME OF THE DEEPER MOISTURE IN NRN ONTARIO PER 12Z CWPL SOUNDING WHICH SHOWED DEEP MOISTURE TO 425MB (20500FT) TO SLIP INTO THE UPPER LAKES. WITH 850MB TEMPS FALLING TO -18C BY 12Z MON...A 3KFT THICK DGZ LAYER FALLS NICELY INTO THE CONVECTIVE LAYER WHERE NAM INDICATES RATHER VIGOROUS UPWARD MOTION TONIGHT. WITH EQUILIBRIUM LEVELS LIKELY ABOVE 10KFT... LES SHOULD GET GOING AT A PRETTY GOOD CLIP...BUT THE LES WILL LIKELY TAKE SOME TIME TO GET FULLY DEVELOPED AND ORGANIZED AS THE TYPICAL DISRUPTIVE EFFECTS OF SPRING DAYTIME HEATING ON LES WILL NEED TO BE ERODED AWAY FIRST. ALTHOUGH IT`S NOT ESPECIALLY COLD YET...NOTE THAT THE LAKE IS HAVING MORE OF A STABILIZING INFLUENCE WITH LESS CLOUD OVER THE WATER THAN LAND...EXCEPT RIGHT IN THE VCNTY OF THE SFC LOW. THE OVERNIGHT PERIOD THRU MON MORNING SHOULD BE THE PRIME PERIOD OF LES...AND THE GOING ADVY LOOKS ON TRACK FOR THE ERN COUNTIES ALONG LAKE SUPERIOR. WILL PROBABLY SEE SOME ACCUMULATIONS UP TO 6-7 INCHES BY MON AFTN. CONSIDERABLE BLSN WILL ALSO BE AN ISSUE...ESPECIALLY IN OPEN AREAS NEAR LAKE SUPERIOR. THE W WILL BE MORE ON THE FRINGE OF THE DEEPER MOISTURE PLUS FCST SOUNDINGS SHOW MORE OF A WELL MIXED BOUNDARY LAYER LINGERING THRU THE NIGHT WHICH ARGUES FOR LIGHTER LES THAN OVER THE E. ACCUMULATIONS TONIGHT THRU EARLY MON AFTN SHOULD BE IN THE 1-4 INCH RANGE OVER THE W... INCLUDING INTO THE HIGHER TERRAIN OF NW MARQUETTE COUNTY. CONDITIONS REMAIN FAVORABLE FOR LES MON AS 850MB TEMPS ONLY RISE A DEGREE OR TWO IN THE AFTN. MOISTURE PROFILE REMAINS DEEP OVER THE E...BUT DOES BECOME MORE SHALLOW OVER THE W. SO LES WILL DIMINISH OVER THE W. EVEN OVER THE E...EXPECT LES TO BEGIN TO DIMINISH IN THE AFTN AS STRONG DAYTIME HEATING DISRUPTS LES PROCESSES. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 451 PM EDT SUN MAR 31 2013 LAKE EFFECT WILL BE ONGOING AT THE START OF THE LONGER TERM PERIOD ON MONDAY NIGHT. INVERSIONS 6-8KFT AND DELTA T/S AROUND 18C WITH LAKE EQL NEARING 10KFT INDICATE NW FLOW AREAS EAST OF MARQUETTE WILL CONTINUE TO SEE LIGHT AND MAYBE MODERATE SNOW ACCUMS AND CONTINUING BLOWING SNOW. HEAVIER SNOW LIKELY OCCURS OVERNIGHT MONDAY NIGHT THROUGH EARLY TUESDAY MORNING WHEN DIURNAL DISRUPTION IS MINIMAL AND WHEN LOW-LEVEL CONVERGENCE IS STRONGEST. POSSIBLE THAT MORE ADVISORIES MAY BE NEEDED MONDAY NIGHT THROUGH TUESDAY MORNING IN AREAS THAT ARE CURRENTLY IN A HEADLINE. SFC-H85 FLOW BECOMES INCREASINGLY ANTICYCLONIC TUESDAY WHICH OFFSETS SUFFICIENT OVER-WATER INSTABILITY AS H85 TEMPS STAY AOB -15C THROUGH 18Z TUESDAY. GFS SOUNDINGS SHOW INVERSION FALLING BLO 5KFT OVR WEST AFT 12Z AND TO AROUND 5KFT FOR AREAS OVR EASTERN CWA. NO ADDITIONAL DEEPER MOISTURE AND CYCLONIC FLOW AT A MINIMUM SHOULD COMBINE WITH HIGHER EARLY APRIL SUN ANGLE/BLYR HEATING TO CONSIDERABLY DISRUPT LAKE EFFECT BY TUESDAY AFTN. GFS/GEM-NH SLIGHTLY LOWER WITH HEIGHTS AND COLDER AT H85 FARTHER WEST TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. RESULT IS AT LEAST ISOLD LK EFFECT CONTINUING OVER FAR EASTERN CWA. ECMWF MORE PROGRESSIVE WITH HEIGHTS AND KEEPS COLDER AIR ON THE MOVE LEADING TO LESS OF CHANCE OF LK EFFECT INTO WEDNESDAY. SOME HINT OF ANOTHER WEAKER TROUGH UPSTREAM THAT WILL HAVE TO DROP ACROSS THE UPPER LAKES AS LARGER TROUGH MOVES TO EAST. WILL HEDGE FORECAST TOWARD GFS/GEM-NH IDEA. SHORTWAVE RIDGING SLIDES ACROSS AREA FOR WEDNESDAY. LINGERING LK EFFECT CLOUDS/FLURRIES IN THE MORNING EAST...BUT THIS SHOULD BREAK UP IN AFTN WITH ARRIVAL OF SFC-H925 RIDGE. MAY SEE INCREASING HIGH CLOUDS OVER WEST BY LATE AFTN. OTHERWISE...A WARMER DAY SHAPING UP WITH LIGHT WINDS/LAKE BREEZES. MIXING TO H9-H85 SUPPORTS MAX TEMPS AS WARM AS LOWER 40S IN THE WEST AND STILL ABOVE THE FREEZING MARK ELSEWHERE. HIGH CLOUDS SPILLING IN LATE ON WEDNESDAY ARE IN ADVANCE OF SHORTWAVE TROUGH TRACKING ACROSS NORTHERN MANITOBA AND NORTHERN ONTARIO. MODELS STILL AT ODDS HOW QUICKLY THIS SYSTEM MOVES THROUGH WEDNESDAY NIGHT AND THURSDAY. 00Z GFS WAS SLOWER BUT 06Z LOOKS MORE LIKE ECMWF. GEM-NH WRAPPED UP AND SLOWER. HEIGHT FALLS AND H7-H5 Q-VECTOR CONVERGENCE FOCUS MOST PRECIPITATION WELL TO NORTH OF LK SUPERIOR. SFC-H85 FRONT/1000-850MB MOISTURE CONVERGENCE SWINGING ACROSS LK SUPERIOR AND UPR MICHIGAN...ALONG WITH RIBBON OF HIGHER H85-H7 MOISTURE...H85 MOISTURE/TEMPERATURE ADVECTION AND STEEPER H7-H5 LAPSE RATES AOA 6.5C/KM NOSING IN FROM WEST ADD UP TO BRIEF PERIOD OF SCATTERED PRECIPITATION AS FRONT WORKS THROUGH. IF TIMING IS LIKE ECMWF...THEN BETTER CHANCES WILL BE IN THE NORTH. IF TIMING ENDS UP SLOWER...THEN MORE AREAS SEE CHANCES AS HEATING OF THE DAY COMBINES WITH THE FORCING. EVEN WITH SLOWER IDEA...MOST PRECIP SHOULD BE OUT OF AREA BY MID AFTN. PTYPE ALSO DEPENDS ON TIMING AS A LATER ARRIVAL WOULD BRING RAIN POTENTIAL INTO MIX. FOR NOW...LOOKS LIKE MOSTLY SNOW AS SOUNDINGS INDICATE WET BULB FALLS BLO ZERO EXCEPT FOR FAR LOWEST REACHES OF BLYR. ONCE FRONT MOVES THROUGH QUIET WEATHER EXPECTED THROUGH FRIDAY AS HIGH PRESSURE DRIFTS ACROSS. GFS A FEW DEGREES COLDER AT H85 ON FRIDAY COMPARED TO ECMWF AND THUS HAS MORE IN WAY OF LAKE EFFECT CLOUDS. SYSTEM FOR NEXT WEEKEND STILL SHOWING UP...BUT THERE REMAIN SOME BIG QUESTIONS. UPPER LAKES REMAINS ON SOUTHERN EDGE OF STRONGER JET STREAM RIDING ALONG SOUTHERN TIER OF CANADA...WHICH WILL HELP ENHANCE PRECIPITATION ALONG SFC-H85 BAROCLINIC ZONE. WHERE THAT ZONE IS LOCATED IS UNCERTAIN. AS MID-LEVEL FLOW BECOMES MORE WESTERLY... SHORTWAVE TROUGH AND SFC-H85 LOWS MOVE FROM ROCKIES ACROSS THE NORTHERN PLAINS INTO WESTERN GREAT LAKES. OPERATIONAL MODELS FROM LAST NIGHT AND NAEFS ENSEMBLES INDICATED SLOWER ARRIVAL TO PRECIPITATION NOT IMPACTING MUCH OF UPR MICHIGAN UNTIL SATURDAY NIGHT. OF COURSE THE 12Z MODELS HAVE TRENDED QUICKER AGAIN. ECMWF IS A LOT QUICKER...BRINGING QPF OVER MOST OF UPR MICHIGAN BY 12Z SATURDAY...AND BASED ON 1000-500MB THICKNESS/H85 TEMPS IS SHOWING BETTER SHOT AT MIXED PRECIPITATION. KIND OF SEEMS LIKE ECMWF IS SHOWING TWO SEPARATE WAVES OF QPF AND THAT IS WHY IT APPEARS MUCH FASTER WITH QPF ARRIVAL. POOR RUN-TO-RUN CONSISTENCY CONTINUES WITH THE SYSTEM. UNTIL CONSISTENCY IMPROVES WILL KEEP WITH CONSENSUS OF MODELS FOR THIS SYSTEM FOR POPS. ENOUGH OF A SIGNAL FROM MODELS OVER LAST COUPLE DAYS TO GO WITH RAIN AND SNOW FOR PTYPE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 129 AM EDT MON APR 1 2013 INCREASINGLY COLDER AIR MOVING ACROSS LAKE SUPERIOR IN NW FLOW WILL SUSTAIN PERIODS OF LAKE EFFECT SNOW SHOWERS AND MVFR CONDITIONS INTO MONDAY AT ALL 3 TAF SITES. GUSTY NW WINDS TO 25 KTS AT TIMES COULD ALSO CONTRIBUTE TO LOWER IFR VSBYS IN SNOW AND BLOWING SNOW...MAINLY AT MORE EXPOSED KCMX SITE. WINDS BACKING A BIT MORE TO THE WNW...SHOULD REDUCE CHCS FOR LAKE EFFECT SNOW SHOWERS AT KSAW BY MONDAY AFTERNOON...PERHAPS EVEN LEADING TO VFR CONDITIONS BY MONDAY EVENING. ARRIVAL OF DRIER NEAR SFC AIR SHOWN ON THE 00Z INL RAOB WILL ALSO BRING ABOUT LONG PERIODS OF VFR CONDITIONS AT IWD. THE COMBINATION OF THE DRYING AND DAYTIME HEATING THIS AFTN WILL DIMINISH THE LES INTENSITY AT CMX AS WELL. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 451 PM EDT SUN MAR 31 2013 STRONG NORTH TO NORTHWEST GALES TO 45 KTS INTO EARLY THIS EVENING AS COLD FRONT CROSSES LK SUPERIOR. STRONGEST WINDS OCCUR THROUGH LATE EVENING IN CORRIDOR FROM CNTRL LK SUPERIOR BUOY TO STANNARD ROCK AND ACROSS REST OF EASTERN LK SUPERIOR. GALES CONTINUE THROUGH MONDAY AND MONDAY NIGHT OVER SAME AREAS...BUT NOT QUITE AS STRONG. WINDS DIMINISH TO LESS THAN 25 KTS BY WEDNESDAY MORNING AS BRIEF RIDGING MOVES ACROSS. STRONGER SOUTHWEST WINDS TO 30 KTS THEN EXPECTED WEDNESDAY NIGHT AND THURSDAY MORNING AS LOW PRESSURE CROSSES NORTHERN ONTARIO AND DRAGS COLD FRONT ACROSS LK SUPERIOR. NORTHWEST WINDS TO 25 KTS DEVELOP BEHIND THE FRONT INTO NEXT WEEKEND. THE STRONG WINDS WILL DRAW MUCH COLDER AIR INTO THE UPPER LAKES EARLY THIS WEEK RESULTING IN FREEZING SPRAY THROUGH TUESDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ007. LAKE EFFECT SNOW WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006-085. LAKE SUPERIOR... GALE WARNING UNTIL 6 AM EDT TUESDAY FOR LSZ250-251-266-267. GALE WARNING UNTIL 6 PM EDT THIS EVENING FOR LSZ244-245-264-265. GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249. LAKE MICHIGAN... NONE. && $$ UPDATE...KC SHORT TERM...ROLFSON LONG TERM...JLA AVIATION...VOSS/KC MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
138 AM EDT MON APR 1 2013 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 451 PM EDT SUN MAR 31 2013 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF DEEPENING INTO THE GREAT LAKES REGION. VIGOROUS SHORTWAVE WAS PASSING OVER LAKE SUPERIOR. PER SATELLITE IMAGERY AND CANADIAN RADAR IMAGERY...AN ASSOCIATED IMPRESSIVE LOOKING SMALL SWATH OF MDT TO HVY SNOW HAS PASSED JUST N OF THE FCST AREA ACROSS FAR NRN LAKE SUPERIOR/ADJACENT ONTARIO TODAY...ALONG/JUST N OF SHORTWAVE TRACK. AN INCREASINGLY WELL-DEFINED SFC LOW PRES IS ORGANIZING OVER EASTERN LAKE ATTM PER VIS SATELLITE IMAGERY. TO THE S...-SHSN TODAY HAVE DEFINITELY TAKEN ON A SPRINGTIME DIURNAL LAND BASED LOOK WITH UNORGANIZED SCT/NMRS COVERAGE. WELL-MIXED LAYER HAS PREVENTED SOME OF THE PCPN FROM REACHING THE GROUND. UPSTREAM 12Z KINL SOUNDING SHOWED A DEEP MOISTURE PROFILE TO 650MB (AROUND 11KFT)... AND MODIFYING SOUNDING FOR A SFC T/TD IN THE LWR 30S/LWR 20S YIELDED SBCAPE AROUND 100J/KG...AND THUS THE DIURNAL COMPONENT TO THE -SHSN THIS AFTN. MAIN FCST ISSUES TONIGHT/MON ARE POTENTIAL LES ACCUMULATIONS AS WELL AS WINDS. FIRST UP...WINDS. EXPECT STRONGEST WINDS TO OCCUR FROM NOW THRU THE ABOUT MID EVENING AS AREA OF 4MB/3HR PRES RISES CURRENTLY JUST NW OF LAKE SUPERIOR SETTLES SE. THE DEEPENING INCREASINGLY WELL-DEFINED SFC LOW OVER ERN LAKE SUPERIOR IS A CONCERN AS IT WILL SERVE TO STRENGTHEN ISALLOBARIC WINDS. SOME OF THE HIGHER RES MODEL GUIDANCE SEEMS TO BE PICKING UP ON THIS AS A SMALL 5-6MB/3HR PRES RISE MAX DEVELOPS OVER CNTRL/ERN LAKE SUPERIOR WITHIN THE LARGER SCALE PRES RISES. THE IMPACT OF THE DEEPENING LOW HAS ALREADY MADE AN IMPACT AS WINDS HAVE GUSTED TO 50MPH AT KP59. THIS SHOULD BE A GOOD INDICATION OF WHAT IS TO COME IN THE NEXT FEW HRS TO THE E OF MARQUETTE. WIND ADVY HAS BEEN ISSUED FOR KEWEENAW COUNTY INTO MID EVENING TO ACCOUNT FOR STRONG WINDS OVER THE NEXT FEW HRS. AS FOR SNOW...NNW CYCLONIC FLOW SHOULD ALLOW SOME OF THE DEEPER MOISTURE IN NRN ONTARIO PER 12Z CWPL SOUNDING WHICH SHOWED DEEP MOISTURE TO 425MB (20500FT) TO SLIP INTO THE UPPER LAKES. WITH 850MB TEMPS FALLING TO -18C BY 12Z MON...A 3KFT THICK DGZ LAYER FALLS NICELY INTO THE CONVECTIVE LAYER WHERE NAM INDICATES RATHER VIGOROUS UPWARD MOTION TONIGHT. WITH EQUILIBRIUM LEVELS LIKELY ABOVE 10KFT... LES SHOULD GET GOING AT A PRETTY GOOD CLIP...BUT THE LES WILL LIKELY TAKE SOME TIME TO GET FULLY DEVELOPED AND ORGANIZED AS THE TYPICAL DISRUPTIVE EFFECTS OF SPRING DAYTIME HEATING ON LES WILL NEED TO BE ERODED AWAY FIRST. ALTHOUGH IT`S NOT ESPECIALLY COLD YET...NOTE THAT THE LAKE IS HAVING MORE OF A STABILIZING INFLUENCE WITH LESS CLOUD OVER THE WATER THAN LAND...EXCEPT RIGHT IN THE VCNTY OF THE SFC LOW. THE OVERNIGHT PERIOD THRU MON MORNING SHOULD BE THE PRIME PERIOD OF LES...AND THE GOING ADVY LOOKS ON TRACK FOR THE ERN COUNTIES ALONG LAKE SUPERIOR. WILL PROBABLY SEE SOME ACCUMULATIONS UP TO 6-7 INCHES BY MON AFTN. CONSIDERABLE BLSN WILL ALSO BE AN ISSUE...ESPECIALLY IN OPEN AREAS NEAR LAKE SUPERIOR. THE W WILL BE MORE ON THE FRINGE OF THE DEEPER MOISTURE PLUS FCST SOUNDINGS SHOW MORE OF A WELL MIXED BOUNDARY LAYER LINGERING THRU THE NIGHT WHICH ARGUES FOR LIGHTER LES THAN OVER THE E. ACCUMULATIONS TONIGHT THRU EARLY MON AFTN SHOULD BE IN THE 1-4 INCH RANGE OVER THE W... INCLUDING INTO THE HIGHER TERRAIN OF NW MARQUETTE COUNTY. CONDITIONS REMAIN FAVORABLE FOR LES MON AS 850MB TEMPS ONLY RISE A DEGREE OR TWO IN THE AFTN. MOISTURE PROFILE REMAINS DEEP OVER THE E...BUT DOES BECOME MORE SHALLOW OVER THE W. SO LES WILL DIMINISH OVER THE W. EVEN OVER THE E...EXPECT LES TO BEGIN TO DIMINISH IN THE AFTN AS STRONG DAYTIME HEATING DISRUPTS LES PROCESSES. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 451 PM EDT SUN MAR 31 2013 LAKE EFFECT WILL BE ONGOING AT THE START OF THE LONGER TERM PERIOD ON MONDAY NIGHT. INVERSIONS 6-8KFT AND DELTA T/S AROUND 18C WITH LAKE EQL NEARING 10KFT INDICATE NW FLOW AREAS EAST OF MARQUETTE WILL CONTINUE TO SEE LIGHT AND MAYBE MODERATE SNOW ACCUMS AND CONTINUING BLOWING SNOW. HEAVIER SNOW LIKELY OCCURS OVERNIGHT MONDAY NIGHT THROUGH EARLY TUESDAY MORNING WHEN DIURNAL DISRUPTION IS MINIMAL AND WHEN LOW-LEVEL CONVERGENCE IS STRONGEST. POSSIBLE THAT MORE ADVISORIES MAY BE NEEDED MONDAY NIGHT THROUGH TUESDAY MORNING IN AREAS THAT ARE CURRENTLY IN A HEADLINE. SFC-H85 FLOW BECOMES INCREASINGLY ANTICYCLONIC TUESDAY WHICH OFFSETS SUFFICIENT OVER-WATER INSTABILITY AS H85 TEMPS STAY AOB -15C THROUGH 18Z TUESDAY. GFS SOUNDINGS SHOW INVERSION FALLING BLO 5KFT OVR WEST AFT 12Z AND TO AROUND 5KFT FOR AREAS OVR EASTERN CWA. NO ADDITIONAL DEEPER MOISTURE AND CYCLONIC FLOW AT A MINIMUM SHOULD COMBINE WITH HIGHER EARLY APRIL SUN ANGLE/BLYR HEATING TO CONSIDERABLY DISRUPT LAKE EFFECT BY TUESDAY AFTN. GFS/GEM-NH SLIGHTLY LOWER WITH HEIGHTS AND COLDER AT H85 FARTHER WEST TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. RESULT IS AT LEAST ISOLD LK EFFECT CONTINUING OVER FAR EASTERN CWA. ECMWF MORE PROGRESSIVE WITH HEIGHTS AND KEEPS COLDER AIR ON THE MOVE LEADING TO LESS OF CHANCE OF LK EFFECT INTO WEDNESDAY. SOME HINT OF ANOTHER WEAKER TROUGH UPSTREAM THAT WILL HAVE TO DROP ACROSS THE UPPER LAKES AS LARGER TROUGH MOVES TO EAST. WILL HEDGE FORECAST TOWARD GFS/GEM-NH IDEA. SHORTWAVE RIDGING SLIDES ACROSS AREA FOR WEDNESDAY. LINGERING LK EFFECT CLOUDS/FLURRIES IN THE MORNING EAST...BUT THIS SHOULD BREAK UP IN AFTN WITH ARRIVAL OF SFC-H925 RIDGE. MAY SEE INCREASING HIGH CLOUDS OVER WEST BY LATE AFTN. OTHERWISE...A WARMER DAY SHAPING UP WITH LIGHT WINDS/LAKE BREEZES. MIXING TO H9-H85 SUPPORTS MAX TEMPS AS WARM AS LOWER 40S IN THE WEST AND STILL ABOVE THE FREEZING MARK ELSEWHERE. HIGH CLOUDS SPILLING IN LATE ON WEDNESDAY ARE IN ADVANCE OF SHORTWAVE TROUGH TRACKING ACROSS NORTHERN MANITOBA AND NORTHERN ONTARIO. MODELS STILL AT ODDS HOW QUICKLY THIS SYSTEM MOVES THROUGH WEDNESDAY NIGHT AND THURSDAY. 00Z GFS WAS SLOWER BUT 06Z LOOKS MORE LIKE ECMWF. GEM-NH WRAPPED UP AND SLOWER. HEIGHT FALLS AND H7-H5 Q-VECTOR CONVERGENCE FOCUS MOST PRECIPITATION WELL TO NORTH OF LK SUPERIOR. SFC-H85 FRONT/1000-850MB MOISTURE CONVERGENCE SWINGING ACROSS LK SUPERIOR AND UPR MICHIGAN...ALONG WITH RIBBON OF HIGHER H85-H7 MOISTURE...H85 MOISTURE/TEMPERATURE ADVECTION AND STEEPER H7-H5 LAPSE RATES AOA 6.5C/KM NOSING IN FROM WEST ADD UP TO BRIEF PERIOD OF SCATTERED PRECIPITATION AS FRONT WORKS THROUGH. IF TIMING IS LIKE ECMWF...THEN BETTER CHANCES WILL BE IN THE NORTH. IF TIMING ENDS UP SLOWER...THEN MORE AREAS SEE CHANCES AS HEATING OF THE DAY COMBINES WITH THE FORCING. EVEN WITH SLOWER IDEA...MOST PRECIP SHOULD BE OUT OF AREA BY MID AFTN. PTYPE ALSO DEPENDS ON TIMING AS A LATER ARRIVAL WOULD BRING RAIN POTENTIAL INTO MIX. FOR NOW...LOOKS LIKE MOSTLY SNOW AS SOUNDINGS INDICATE WET BULB FALLS BLO ZERO EXCEPT FOR FAR LOWEST REACHES OF BLYR. ONCE FRONT MOVES THROUGH QUIET WEATHER EXPECTED THROUGH FRIDAY AS HIGH PRESSURE DRIFTS ACROSS. GFS A FEW DEGREES COLDER AT H85 ON FRIDAY COMPARED TO ECMWF AND THUS HAS MORE IN WAY OF LAKE EFFECT CLOUDS. SYSTEM FOR NEXT WEEKEND STILL SHOWING UP...BUT THERE REMAIN SOME BIG QUESTIONS. UPPER LAKES REMAINS ON SOUTHERN EDGE OF STRONGER JET STREAM RIDING ALONG SOUTHERN TIER OF CANADA...WHICH WILL HELP ENHANCE PRECIPITATION ALONG SFC-H85 BAROCLINIC ZONE. WHERE THAT ZONE IS LOCATED IS UNCERTAIN. AS MID-LEVEL FLOW BECOMES MORE WESTERLY... SHORTWAVE TROUGH AND SFC-H85 LOWS MOVE FROM ROCKIES ACROSS THE NORTHERN PLAINS INTO WESTERN GREAT LAKES. OPERATIONAL MODELS FROM LAST NIGHT AND NAEFS ENSEMBLES INDICATED SLOWER ARRIVAL TO PRECIPITATION NOT IMPACTING MUCH OF UPR MICHIGAN UNTIL SATURDAY NIGHT. OF COURSE THE 12Z MODELS HAVE TRENDED QUICKER AGAIN. ECMWF IS A LOT QUICKER...BRINGING QPF OVER MOST OF UPR MICHIGAN BY 12Z SATURDAY...AND BASED ON 1000-500MB THICKNESS/H85 TEMPS IS SHOWING BETTER SHOT AT MIXED PRECIPITATION. KIND OF SEEMS LIKE ECMWF IS SHOWING TWO SEPARATE WAVES OF QPF AND THAT IS WHY IT APPEARS MUCH FASTER WITH QPF ARRIVAL. POOR RUN-TO-RUN CONSISTENCY CONTINUES WITH THE SYSTEM. UNTIL CONSISTENCY IMPROVES WILL KEEP WITH CONSENSUS OF MODELS FOR THIS SYSTEM FOR POPS. ENOUGH OF A SIGNAL FROM MODELS OVER LAST COUPLE DAYS TO GO WITH RAIN AND SNOW FOR PTYPE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 129 AM EDT MON APR 1 2013 INCREASINGLY COLDER AIR MOVING ACROSS LAKE SUPERIOR IN NW FLOW WILL SUSTAIN PERIODS OF LAKE EFFECT SNOW SHOWERS AND MVFR CONDITIONS INTO MONDAY AT ALL 3 TAF SITES. GUSTY NW WINDS TO 25 KTS AT TIMES COULD ALSO CONTRIBUTE TO LOWER IFR VSBYS IN SNOW AND BLOWING SNOW...MAINLY AT MORE EXPOSED KCMX SITE. WINDS BACKING A BIT MORE TO THE WNW...SHOULD REDUCE CHCS FOR LAKE EFFECT SNOW SHOWERS AT KSAW BY MONDAY AFTERNOON...PERHAPS EVEN LEADING TO VFR CONDITIONS BY MONDAY EVENING. ARRIVAL OF DRIER NEAR SFC AIR SHOWN ON THE 00Z INL RAOB WILL ALSO BRING ABOUT LONG PERIODS OF VFR CONDITIONS AT IWD. THE COMBINATION OF THE DRYING AND DAYTIME HEATING THIS AFTN WILL DIMINISH THE LES INTENSITY AT CMX AS WELL. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 451 PM EDT SUN MAR 31 2013 STRONG NORTH TO NORTHWEST GALES TO 45 KTS INTO EARLY THIS EVENING AS COLD FRONT CROSSES LK SUPERIOR. STRONGEST WINDS OCCUR THROUGH LATE EVENING IN CORRIDOR FROM CNTRL LK SUPERIOR BUOY TO STANNARD ROCK AND ACROSS REST OF EASTERN LK SUPERIOR. GALES CONTINUE THROUGH MONDAY AND MONDAY NIGHT OVER SAME AREAS...BUT NOT QUITE AS STRONG. WINDS DIMINISH TO LESS THAN 25 KTS BY WEDNESDAY MORNING AS BRIEF RIDGING MOVES ACROSS. STRONGER SOUTHWEST WINDS TO 30 KTS THEN EXPECTED WEDNESDAY NIGHT AND THURSDAY MORNING AS LOW PRESSURE CROSSES NORTHERN ONTARIO AND DRAGS COLD FRONT ACROSS LK SUPERIOR. NORTHWEST WINDS TO 25 KTS DEVELOP BEHIND THE FRONT INTO NEXT WEEKEND. THE STRONG WINDS WILL DRAW MUCH COLDER AIR INTO THE UPPER LAKES EARLY THIS WEEK RESULTING IN FREEZING SPRAY THROUGH TUESDAY NIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WINTER WEATHER ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR MIZ006- 007-085. LAKE SUPERIOR... GALE WARNING UNTIL 6 AM EDT TUESDAY FOR LSZ250-251-266-267. GALE WARNING UNTIL 6 PM EDT THIS EVENING FOR LSZ244-245-264-265. GALE WARNING UNTIL 5 PM EDT THIS AFTERNOON FOR LSZ249. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...JLA AVIATION...VOSS/KC MARINE...JLA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1030 AM EDT MON APR 1 2013 .SYNOPSIS... A WEAK FRONT WILL MOVE THROUGH AND BRING SCATTERED RAIN SHOWERS THROUGH THIS AFTERNOON. A STRONGER FRONT WILL MOVE THROUGH TONIGHT USHERING IN COOL AIR FOR THE MID WEEK PERIOD. GULF OF MEXICO LOW PRESSURE WILL MOVE UP THE CAROLINA COAST FRIDAY BRINGING A SOAKING RAIN. NEXT WEEKEND SHOULD BE FAIR AND SEASONABLE. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM MONDAY...SEVERAL FEATURES WORKING TOGETHER TO BRING US SOME SHOWERS THIS MORNING...AND THESE WILL LINGER INTO THE EARLY AFTN BEFORE RAPID DRYING OCCURS LATER TODAY. PRECIP ONGOING AT THIS HOUR IS DRIVEN PRIMARILY BY A VORT MAX MOVING ACROSS SC. THIS WILL CONTINUE TO WORK EAST THROUGH THE AFTN...CONTINUING THE CHANCES FOR SHOWERS. BUFR PROFILES SUGGEST INCREASING INSTABILITY AHEAD OF THE UPPER FEATURE...ESPECIALLY ACROSS SOUTHERN ZONES WHICH WILL BE MORE DIRECTLY IMPACTED BY THE IMPULSE MOVING OVERHEAD. HAVE INTRODUCED ISO -TRW FOR THE EXTREME SOUTHERN ZONES SINCE THERE APPEARS TO BE ENOUGH LIFT AND INSTABILITY FOR AN ISOLATED LIGHTNING STRIKE THROUGH THE AFTN...BUT NOTHING WIDESPREAD...AND ANY CHC FOR THUNDER WILL END QUICKLY AS VORT SKIRTS OFFSHORE. WEAK COLD FRONT...AND I DON`T LIKE THE TERM COLD FRONT DUE TO LACK OF ANY TEMP GRADIENT...WILL DROP SOUTH THIS AFTN BEHIND THE DEPARTING SHORTWAVE. THE COMBINATION OF SOME SUBSIDENCE BEHIND THIS SHORTWAVE AND DRYING BEHIND THE COLD FRONT (TROUGH) WILL BRING AN END TO THE SHOWERS EARLY THIS AFTN...WITH RAPID DRYING OCCURRING IN THE COLUMN THEREAFTER. THIS DRYING WILL ALLOW FOR SOME SUN TO PEEK THROUGH THIS AFTN/EVE...AND HIGH TEMPS WILL STILL REACH TO 70 OR HIGHER EVEN BEHIND THE "COLD FRONT" THANKS TO THE APRIL INSOLATION. A MORE SIGNIFICANT COLD FRONT...THIS ONE ACCOMPANIED BY REAL CAA...WILL DROP SOUTH TONIGHT AND TEMPS WILL PLUMMET BEHIND IT. THE EXACT TIMING IS STILL IN QUESTION...BUT IT APPEARS THIS FRONT WILL DROP THROUGH THE CWA AFTER MIDNIGHT AND HELP MINS FALL TO SEASONABLE LEVELS...LOW 40S NORTH TO UPPER 40S SOUTH...AND HAVE LEANED ON THE SLIGHTLY COOLER MAV NUMBERS. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...DEEP UPPER CUTOFF NORTH OF NEW ENGLAND STATES ON TUESDAY HELPING TO PUSH ARCTIC COLD FRONT AND ITS ASSOC MOISTURE OFF TO THE SOUTH OF THE AREA. THE UPPER LOW WILL BE LIFTING OUT TO THE NORTH A BIT HOWEVER AND THIS WILL TEMPER THE STRENGTH OF THE COLD AIR ADVECTION INTO THE CAROLINAS. GUIDANCE HAS COME UP A FEW DEGREES PAST SEVERAL RUNS BUT HAVE OPTED TO REMAIN A FEW DEGREES BELOW AS THE VERY SHALLOW NATURE OF THE COLD AIR MAY BUST THE NUMBERS A BIT. CURRENT FORECAST CAPS HIGHS AT ABOUT 10F BELOW CLIMO. THE SAME DEVIATION FROM NORMAL IS EXPECTED TUESDAY NIGHT WITH LOWS UPPER 30S/NR 40. ATTENTION TURNS TO SOUTHERN BRANCH AS WE HEAD INTO WEDNESDAY. THE NORTHERN STREAM UPPER LOW CONTINUES ITS SLOW LIFTING/PROGRESSING ENERGY MOVING ACROSS TX WILL BEGIN CYCLOGENESIS IN THE WESTERN GULF. WRF READILY SPREADS CLOUD COVER AND INCREASING RAIN CHANCES INTO THE REGION LATE WEDNESDAY AND THEN VERY MUCH SO WEDNESDAY NIGHT. GIVEN THE MID LEVEL CONFLUENCE ALLOWING THE HIGH TO REALLY HANG ON AND THAT DEWPOINTS WILL INITIALIZE PRETTY LOW FEEL THAT THIS IS TOO FAST. END OF PERIOD A COMPROMISE BETWEEN GFS AND WRF. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...VERY RAINY PERIOD TO START THE LONG TERM AS SOUTHERN BRANCH FEATURE TAPS COPIOUS GOMEX MOISTURE AND FLINGS IT UP ACROSS THE CAROLINAS. THERE ARE SOME TIMING DIFFERENCES BETWEEN VARIOUS GUIDANCE BUT THE BULK OF THE RAINFALL APPEARS TO BE SLATED FOR THURSDAY NIGHT INTO FRIDAY MORNING. THEREAFTER DEPENDING ON THE TRACK OF THE LOW A DRY SLOT MAY WORK UP THE COAST. TEMPS ALSO VERY MUCH HINGE ON THE TRACK OF THE STORM AS EASTERN COUNTIES APPEAR LIKELY TO SECURELY WARM SECTOR WHERE INLAND ZONES MAY STRUGGLE A BIT. TOUGH TO SAY HOW QUICK THE DRYING IS LATER FRIDAY DUE TO THE LAGGING OF THE UPPER TROUGH INCLUDING WRAPAROUND RAIN POTENTIAL THOUGH SMALL. HIGH BUILDS IN BEHIND THIS SYSTEM FOR THE WEEKEND AMIDST LOW AMPLITUDE MID LVL FLOW BRINGING A FAIR AMOUNT OF SUN AND CLIMO TEMPS...EVEN PERHAPS A WARMING TREND. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... AS OF 12Z...MOST OF THE RAIN IS OVER THE WESTERN TERMINALS AT THIS TIME. TIME HEIGHTS AND HRRR MODEL ARE IN REASONABLE AGREEMENT IN MOVING THE PRECIP TOWARD THE COAST WITH A FRONT THAT BASICALLY WASHES OUT AFTER IT EXITS THE COAST THIS AFTERNOON. LOOK FOR CONDITIONS TO BOUNCE FROM VFR TO MVFR IN THE PRECIP. ALL AREAS WILL BECOME VFR BY EARLY AFTERNOON AS THE BULK OF THE DEEP MOISTURE SHIFTS TO THE SOUTHEAST. A STRONGER FRONT MOVES IN TONIGHT. NO WEATHER ASSOCIATED WITH IT OTHER THAN A WIND SHIFT TO THE NORTH AND A VFR STRATA CU CEILING. EXTENDED OUTLOOK...VFR TUESDAY AND WEDNESDAY. SHOWERS AND SUB-VFR CONDITIONS LIKELY THURSDAY AND FRIDAY AS LOW PRESSURE MOVES UP THE ATLANTIC COAST. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 AM MONDAY...BUOY 41008 AND 41013 HAVE FINALLY SHOWN THE RAPID DROP OFF WE WERE EXPECTING THIS MORNING...AND DROPPED THE SCA FOR THE NC WATERS AS NEEDED. A SERIES OF COLD FRONTS...THE FIRST QUITE WEAK...WILL DROP SOUTH ACROSS THE WATERS TODAY. THIS FIRST ONE CROSSES LATE THIS AFTN...BRINGING A SLIGHT WIND SHIFT TO W/NW AND AN END TO SHOWERS/TSTMS. THE STRONGER FRONT CROSSES LATE TONIGHT...AND WILL BE ACCOMPANIED BY A STRONG BUT SHORT-LIVED SURGE OF N/NE WINDS APPROACHING 20 KTS. WHILE SEAS MAY TICK UPWARD WITH THIS SURGE...AFTER BEING 2-4 FT MUCH OF THE DAY...DO NOT ANTICIPATE THE NEED FOR ANY CAUTIONARY STATEMENTS OR HEADLINES ATTM. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...MAIN AREA OF HIGH PRESSURE BUILDING IN FROM THE NORTH AND WEST IN A FAIRLY RESTRAINED MANNER ON TUESDAY KEEPING THE CENTER UP IN THE GREAT LAKES. A SMALLER AND POORLY DEFINED CENTER SLIPS INTO THE CAROLINAS HOWEVER KEEPING GRADIENT VERY LIGHT LEADING AND TAME WINDS OUT OF THE N/NE. SEAS BEGIN THE PERIOD STIRRED UP FROM THE NEAR TERM BUT WILL QUICKLY ABATE. THE PARENT AIRMASS DRAWS A LITTLE CLOSER WEDNESDAY PICKING UP AND SLIGHTLY VEERING THE WINDS. AS THE HIGH SETTLES ACRS VA BY THE END OF THE PERIOD AND LOW PRESSURE MARCHES EAST ACROSS THE GULF COAST THERE SHOULD BE AN ADDITIONAL VEER AND SMALL INCREASE IN WINDS. THE SPEED AT WHICH THIS HAPPENS IS A LITTLE UNCERTAIN. .LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...MODERATELY STRONG SOUTHERN BRANCH FEATURE COMING ACROSS THE GULF OF MEXICO ON THURSDAY WHILE WEST ATLANTIC HIGH PRESSURE PROGRESSES EASTWARD BUT AT A SLOWER SPEED. THIS WILL INCREASE THE GRADIENT UP AND DOWN THE SOUTHEAST COAST AND A SMALL CRAFT ADVISORY WILL BE NEEDED. AS THE STORM SYSTEM TURNS TO THE NE AND MOVES RIGHT UP THE CAROLINA COAST ON AN INLAND TRACK THE STRONG SW FLOW WILL BE MAINTAINED IF NOT STRENGTHENED. EXPECT A FURTHER BUILDING OF SEAS FROM ADDED FETCH DURATION IF NOTHING ELSE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...TRA/JDW NEAR TERM...JDW SHORT TERM...MBB LONG TERM...MBB AVIATION...TRA/BJR MARINE...
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
651 AM EDT MON APR 1 2013 .SYNOPSIS... A WEAK FRONT WILL MOVE THROUGH AND BRING WIDESPREAD RAIN THIS MORNING. A STRONGER FRONT WILL MOVE THROUGH TONIGHT USHERING IN COOL AIR FOR THE MID WEEK PERIOD. GULF OF MEXICO LOW PRESSURE WILL MOVE UP THE CAROLINA COAST FRIDAY BRINGING A SOAKING RAIN. NEXT WEEKEND SHOULD BE FAIR AND SEASONABLE. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM MONDAY...LINEAR EXTRAPOLATION OF THE BACK EDGE OF THE RADAR ECHOES ACROSS EASTERN GEORGIA PLACES IT NEAR FLORENCE AROUND 15Z/10:00 AM EDT...AND IN WILMINGTON AROUND 1730Z/1:30 PM EDT. THAT IS LIKELY A LITTLE SLOW GIVEN HOW QUICKLY THE UPPER LEVEL FEATURE AND ITS SUBSEQUENT MID-LEVEL DRYING SHOULD ADVECT EAST TOWARD THE COAST...SO I FEEL COMFORTABLE WITH A FORECAST STILL CALLING FOR THE BULK OF THE PRECIP TO BE OFFSHORE BY NOON. 06Z MODELS MADE NO SIGNIFICANT CHANGES WITH AFTERNOON TEMPERATURES EITHER. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... A COLD FRONT LIES ACROSS NORTH CAROLINA FROM NEAR CHARLOTTE NORTHEAST THROUGH FAYETTEVILLE AND GREENVILLE... SEPARATING SUBTROPICAL AIR TO THE SOUTH FROM A HEAVILY MODIFIED ARCTIC AIRMASS TO THE NORTH. THIS BOUNDARY WILL SAG SOUTH DURING THE DAY...CLEARING THE COASTLINE BY MID TO LATE AFTERNOON. IN THE UPPER LEVELS A 500 MB DISTURBANCE WILL SWEEP OFFSHORE DURING THE LATE MORNING HOURS...TAKING MOST OF THE DEEP-LAYER MOISTURE WITH IT. RADAR COMPOSITES SHOW A CONCENTRATED STREAK OF SHOWERS AND EMBEDDED THUNDERSTORMS EXTENDING FROM CAPE FEAR WESTWARD ACROSS SC TO NEAR ATLANTA. MODEL SOUNDINGS SHOW SOMETHING WE HAVEN`T SEEN A LOT OF THIS YEAR: CONVECTIVE INSTABILITY THROUGH A DEEP LAYER OF THE ATMOSPHERE. CAPE VALUES ARE NOT AND WILL NOT GET VERY HIGH...ONLY A COUPLE HUNDRED J/KG FOR ANY INITIAL PARCEL LEVEL...BUT GIVEN THE SYNOPTIC LIFT OCCURRING IN ADVANCE OF THE SHORTWAVE UPRIGHT CONVECTION HAS DEVELOPED AND MAY CONTINUE THROUGH THE MORNING. RAINFALL AMOUNTS COULD APPROACH HALF AN INCH ACROSS FLORENCE... MARION AND WHITEVILLE THIS MORNING. ONCE THE SHORTWAVE CLEARS THE COAST THERE IS VERY LITTLE SUPPORT REMAINING FOR SHOWER ACTIVITY. CLOUDS SHOULD ALSO DIMINISH... ALTHOUGH MODELS CONTINUE TO PAINT BOTH CIRRUS AND SOME BOUNDARY- LAYER DRIVEN CUMULUS INTO LATE AFTERNOON. SINCE THERE IS LITTLE REAL COLD ADVECTION BEHIND THIS FIRST COLD FRONT HIGHS SHOULD RISE INTO THE LOWER TO MID 70S AWAY FROM THE BEACHES...ACTUALLY A FEW DEGREES ABOVE NORMAL. TONIGHT A SECOND MUCH STRONGER COLD FRONT WILL DIVE IN FROM THE NORTH SHORTLY AFTER MIDNIGHT...ACCOMPANIED BY A SHIFT TO NORTH WINDS AND A MORE IMPRESSIVE SHOT OF COLD ADVECTION. TEMPERATURES WILL FALL IN EARNEST LATE AND LOWS SHOULD REACH THE 40S EVERYWHERE BY DAYBREAK TUESDAY. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...DEEP UPPER CUTOFF NORTH OF NEW ENGLAND STATES ON TUESDAY HELPING TO PUSH ARCTIC COLD FRONT AND ITS ASSOC MOISTURE OFF TO THE SOUTH OF THE AREA. THE UPPER LOW WILL BE LIFTING OUT TO THE NORTH A BIT HOWEVER AND THIS WILL TEMPER THE STRENGTH OF THE COLD AIR ADVECTION INTO THE CAROLINAS. GUIDANCE HAS COME UP A FEW DEGREES PAST SEVERAL RUNS BUT HAVE OPTED TO REMAIN A FEW DEGREES BELOW AS THE VERY SHALLOW NATURE OF THE COLD AIR MAY BUST THE NUMBERS A BIT. CURRENT FORECAST CAPS HIGHS AT ABOUT 10F BELOW CLIMO. THE SAME DEVIATION FROM NORMAL IS EXPECTED TUESDAY NIGHT WITH LOWS UPPER 30S/NR 40. ATTENTION TURNS TO SOUTHERN BRANCH AS WE HEAD INTO WEDNESDAY. THE NORTHERN STREAM UPPER LOW CONTINUES ITS SLOW LIFTING/PROGRESSING ENERGY MOVING ACROSS TX WILL BEGIN CYCLOGENESIS IN THE WESTERN GULF. WRF READILY SPREADS CLOUD COVER AND INCREASING RAIN CHANCES INTO THE REGION LATE WEDNESDAY AND THEN VERY MUCH SO WEDNESDAY NIGHT. GIVEN THE MID LEVEL CONFLUENCE ALLOWING THE HIGH TO REALLY HANG ON AND THAT DEWPOINTS WILL INITIALIZE PRETTY LOW FEEL THAT THIS IS TOO FAST. END OF PERIOD A COMPROMISE BETWEEN GFS AND WRF. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 3 AM MONDAY...VERY RAINY PERIOD TO START THE LONG TERM AS SOUTHERN BRANCH FEATURE TAPS COPIOUS GOMEX MOISTURE AND FLINGS IT UP ACROSS THE CAROLINAS. THERE ARE SOME TIMING DIFFERENCES BETWEEN VARIOUS GUIDANCE BUT THE BULK OF THE RAINFALL APPEARS TO BE SLATED FOR THURSDAY NIGHT INTO FRIDAY MORNING. THEREAFTER DEPENDING ON THE TRACK OF THE LOW A DRY SLOT MAY WORK UP THE COAST. TEMPS ALSO VERY MUCH HINGE ON THE TRACK OF THE STORM AS EASTERN COUNTIES APPEAR LIKELY TO SECURELY WARM SECTOR WHERE INLAND ZONES MAY STRUGGLE A BIT. TOUGH TO SAY HOW QUICK THE DRYING IS LATER FRIDAY DUE TO THE LAGGING OF THE UPPER TROUGH INCLUDING WRAPAROUND RAIN POTENTIAL THOUGH SMALL. HIGH BUILDS IN BEHIND THIS SYSTEM FOR THE WEEKEND AMIDST LOW AMPLITUDE MID LVL FLOW BRINGING A FAIR AMOUNT OF SUN AND CLIMO TEMPS...EVEN PERHAPS A WARMING TREND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 12Z...MOST OF THE RAIN IS OVER THE WESTERN TERMINALS AT THIS TIME. TIME HEIGHTS AND HRRR MODEL ARE IN REASONABLE AGREEMENT IN MOVING THE PRECIP TOWARD THE COAST WITH A FRONT THAT BASICALLY WASHES OUT AFTER IT EXITS THE COAST THIS AFTERNOON. LOOK FOR CONDITIONS TO BOUNCE FROM VFR TO MVFR IN THE PRECIP. ALL AREAS WILL BECOME VFR BY EARLY AFTERNOON AS THE BULK OF THE DEEP MOISTURE SHIFTS TO THE SOUTHEAST. A STRONGER FRONT MOVES IN TONIGHT. NO WEATHER ASSOCIATED WITH IT OTHER THAN A WIND SHIFT TO THE NORTH AND A VFR STRATA CU CEILING. EXTENDED OUTLOOK...VFR TUESDAY AND WEDNESDAY. SHOWERS AND SUB-VFR CONDITIONS LIKELY THURSDAY AND FRIDAY AS LOW PRESSURE MOVES UP THE ATLANTIC COAST. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM MONDAY...SEAS ARE FALLING VERY SLOWLY...BUT BASED ON 6 A.M. BUOY OBS IN THE CAPE FEAR VICINITY THE ADVISORY WILL NEED TO REMAIN POSTED THROUGH AT LEAST 9 A.M. NO SIGNIFICANT CHANGES HAVE BEEN MADE TO THE FORECAST. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... A COLD FRONT ACROSS INTERIOR NORTH CAROLINA WILL DROP SOUTHWARD SLOWLY DURING THE DAY...REACHING THE NORTH AND SOUTH CAROLINA COASTAL WATERS BY LATE AFTERNOON. WINDS WILL GRADUALLY VEER FROM SOUTHWEST TO WEST IN THE VICINITY OF THIS RATHER WEAK FRONT. SHOWER AND THUNDERSTORM ACTIVITY WILL OCCUR THIS MORNING MAINLY NORTH OF MYRTLE BEACH...WITH SHOWERS BECOMING VERY ISOLATED IF NOT TOTALLY ABSENT THIS AFTERNOON. A SECOND BUT MUCH STRONGER COLD FRONT WILL ARRIVE FROM THE NORTH AFTER MIDNIGHT TONIGHT...ACCOMPANIED BY A SHIFT TO NORTH WINDS WITH AN INCREASE IN SPEEDS TO 15-20 KNOTS. AT THIS TIME IT DOESN`T APPEAR SMALL CRAFT ADVISORIES WILL BE NEEDED...BUT CONDITIONS WILL CERTAINLY DETERIORATE LATE. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM MONDAY...MAIN AREA OF HIGH PRESSURE BUILDING IN FROM THE NORTH AND WEST IN A FAIRLY RESTRAINED MANNER ON TUESDAY KEEPING THE CENTER UP IN THE GREAT LAKES. A SMALLER AND POORLY DEFINED CENTER SLIPS INTO THE CAROLINAS HOWEVER KEEPING GRADIENT VERY LIGHT LEADING AND TAME WINDS OUT OF THE N/NE. SEAS BEGIN THE PERIOD STIRRED UP FROM THE NEAR TERM BUT WILL QUICKLY ABATE. THE PARENT AIRMASS DRAWS A LITTLE CLOSER WEDNESDAY PICKING UP AND SLIGHTLY VEERING THE WINDS. AS THE HIGH SETTLES ACRS VA BY THE END OF THE PERIOD AND LOW PRESSURE MARCHES EAST ACROSS THE GULF COAST THERE SHOULD BE AN ADDITIONAL VEER AND SMALL INCREASE IN WINDS. THE SPEED AT WHICH THIS HAPPENS IS A LITTLE UNCERTAIN. .LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 3 AM MONDAY...MODERATELY STRONG SOUTHERN BRANCH FEATURE COMING ACROSS THE GULF OF MEXICO ON THURSDAY WHILE WEST ATLANTIC HIGH PRESSURE PROGRESSES EASTWARD BUT AT A SLOWER SPEED. THIS WILL INCREASE THE GRADIENT UP AND DOWN THE SOUTHEAST COAST AND A SMALL CRAFT ADVISORY WILL BE NEEDED. AS THE STORM SYSTEM TURNS TO THE NE AND MOVES RIGHT UP THE CAROLINA COAST ON AN INLAND TRACK THE STRONG SW FLOW WILL BE MAINTAINED IF NOT STRENGTHENED. EXPECT A FURTHER BUILDING OF SEAS FROM ADDED FETCH DURATION IF NOTHING ELSE. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 9 AM EDT THIS MORNING FOR AMZ250- 252. && $$ SYNOPSIS...TRA NEAR TERM...MBB SHORT TERM...MBB LONG TERM...MBB AVIATION...43
AREA FORECAST DISCUSSION
NWS BISMARCK ND
547 PM CDT MON APR 1 2013 .UPDATE... ISSUED AT 546 PM CDT MON APR 1 2013 LATEST SUITE OF SATELLITE IMAGERY/SURFACE OBSERVATIONS SHOWS CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA WITH THE EXCEPTION OF A SCT/BKN CUMULUS DECK OVER THE HIGHER TERRAIN IN THE SOUTHWEST...IN CONJUNCTION WITH A LOW LEVEL BAROCLINIC ZONE. TEMPERATURES WERE IN THE 50S ACROSS SOUTHEAST MONTANA...WITH TEMPERATURES AROUND 40 IN OUR SOUTHWEST ZONES. OTHERWISE...A 1030MB SURFACE HIGH PRESSURE SITS OVER NORTHERN NORTH DAKOTA THIS EVENING PRODUCING CLEAR SKIES AND LIGHT WINDS. FURTHER UPSTREAM...WATER VAPOR IMAGERY SHOWS A WEAK SHORTWAVE TROUGH ALOFT OVER NORTHEAST SASKATCHEWAN ALONG WITH A SURFACE REFLECTION/SURFACE TROUGH PER MSAS...ALL MOVING SOUTHEAST WITH TIME. THIS SHORTWAVE IS FORECAST TO MOVE TO LAKE WINNIPEG BY 06Z TUESDAY...THEN INTO NORTHERN MINNESOTA BY 12Z TUESDAY. BEST UPWARD VERTICAL MOTION/H85-H3 OMEGA FIELD IS FORECAST OVER SOUTHERN MANITOBA DURING THE 06Z-12Z TUESDAY TIME FRAME. HOWEVER THE 18Z NAM/GFS AND LATEST RAP MODEL PRODUCE A SWATH OF 80 TO 90 PERCENT H85-H7 RH LATER TONIGHT ASSOCIATED WITH THIS SHORTWAVE. THE NAM/GFS ALSO PAINT LIGHT QPF OF 0.01 COVERING PORTIONS OF BOTTINEAU AND ROLETTE COUNTIES BETWEEN 09Z AND 12Z TUESDAY. THE LATEST RAP MODEL KEEPS THE PRECIPITATION JUST EAST OF BOTTINEAU/ROLETTE COUNTIES. OBSERVATIONS AND PAST WEATHER IN LOCATION OF CURRENT SHORTWAVE DOES REVEAL A POCKET OF LOW/MID LEVEL CLOUDS AND A BRIEF PERIOD OF ISOLATED FLURRIES. FOR THIS UPDATE...HAVE COLLABORATED WITH NEIGHBORING OFFICES TO INCREASE THE SKY GRIDS FOR THE NORTHEAST TONIGHT...BUT HOLD OFF ON ANY MENTION OF PRECIPITATION AS BEST VERTICAL MOTION IS FORECAST NORTH/EAST. WILL AWAIT THE 00Z MODEL RUNS AND KEEP A CLOSE EYE ON THE RAP MODEL THIS EVENING FOR ANY CHANGES. UNTIL OBSERVATIONS SUGGEST SOMETHING DEVELOPING CLOSER TO OUR NORTHERN BORDER...WILL STAY THE COURSE WITH THE DRY FORECAST. REST OF FORECAST IS IN GOOD SHAPE. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 346 PM CDT MON APR 1 2013 HIGH PRESSURE WILL GRADUALLY SHIFT EAST OF THE REGION THROUGH THE PERIOD. DRY CONDITIONS WILL PREVAIL AS A RESULT. BELOW NORMAL TEMPERATURES WILL CONTINUE THIS AFTERNOON AND TONIGHT. HOWEVER...RETURN FLOW DEVELOPING ACROSS THE REGION COMBINED WITH NO SNOW PACK SOUTHWEST OF THE MISSOURI WILL ALLOW TUESDAY AFTERNOON HIGHS TO BE ABOVE NORMAL SOUTHWEST. BELOW NORMAL TEMPERATURES WILL CONTINUE NORTH AND EAST OF THE MISSOURI RIVER...WHERE THE SNOW PACK IS LOCATED. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 346 PM CDT MON APR 1 2013 THE MAIN FORECAST CHALLENGES FOR THE EXTENDED PERIOD INCLUDE PRECIPITATION CHANCES AND PRECIPITATION TYPE. 12Z SUITE OF MODEL SOLUTIONS ARE IN AGREEMENT EARLY IN THE PERIOD...WITH SOLUTIONS DIVERGING LATE THIS WEEK. WARM AIR ADVECTION WILL CONTINUE ACROSS THE AREA TUESDAY NIGHT AND WEDNESDAY AHEAD OF A UPPER LEVEL WAVE/SURFACE LOW PRESSURE SYSTEM THAT IS FORECAST TO PASS OVER NORTH DAKOTA. WARM H850 TEMPERATURES OF +6 TO +10C WILL BE FIRMLY IN PLACE WEDNESDAY AS PRECIPITATION BEGINS ACROSS THE NORTHWEST AND SPREADS SOUTHEAST ACROSS THE AREA WEDNESDAY. PRECIPITATION WILL BEGIN AS LIGHT FREEZING RAIN AND TRANSITION TO LIGHT RAIN DURING WEDNESDAY AFTERNOON. ACROSS THE SOUTHWEST...ISOLATED WEAK THUNDERSTORMS ARE POSSIBLE...WHERE TEMPERATURES WILL BE IN THE 60S WITH SURFACE BASED CAPE IN THE 100 TO 200 J/KG ADVERTISED BY THE 12Z NAM. BEFORE ENDING WEDNESDAY EVENING...A TRANSITION FROM LIGHT RAIN TO A WINTRY MIX OF SNOW...FREEZING RAIN...AND POSSIBLY SLEET WILL BE SEEN AS A COLD FRONT MOVES SOUTH FROM CANADA. COOLER TEMPERATURES WILL BE SEEN WEDNESDAY NIGHT AND THURSDAY...AS COLD AIR COMMENCES FOLLOWING THE PASSAGE OF THE AFOREMENTIONED COLD FRONT. HOWEVER...ACROSS THE SNOW LESS AREAS...TEMPERATURES WILL BE WARMEST WITH TEMPERATURES IN 50S ON THURSDAY. FOR LOCATIONS ACROSS THE SNOWPACK...TEMPERATURES WILL BE IN THE LOW TO MID 30S. STARTING FRIDAY...AN ACTIVE PERIOD OF WEATHER IS EXPECTED TO START AS A SERIES OF UPPER LEVEL WAVES AND THEIR SURFACE REFLECTIONS ARE PROGGED TO MOVE ACROSS THE AREA IN NORTHWESTERLY FLOW. UNCERTAINTY REMAINS IN THE PLACEMENT AND TYPE OF PRECIPITATION ACROSS NORTH DAKOTA...AS THERE IS DISAGREEMENT AMONGST THE 12Z MODEL SOLUTIONS. THE 12Z GEM/GFS ARE MORE AGGRESSIVE WITH QPF ACROSS THE WEST AND CENTRAL VERSUS THE 12Z EC SOLUTION. THE 12Z EC KEEPS THE BULK OF THE PRECIPITATION FURTHER NORTH ACROSS SOUTHERN MANITOBA AND SASKATCHEWAN. AT THIS TIME HAVE UTILIZED A BLEND OF MODEL SOLUTIONS DURING THE FRIDAY TO MONDAY PERIOD...WHICH GIVE A WIDE ARRAY OF PRECIPITATION TYPES. AT THIS MOMENT...IT LOOKS LIKE THE SOUTHWEST WILL REMAIN MOSTLY RAIN AS IT REMAINS IN THE WARM H850 TEMPERATURES OF +4 TO +8 C. ELSEWHERE...A LIGHT WINTRY MIX OF SNOW...FREEZING RAIN...AND POSSIBLY SLEET MAY OCCUR. BY SUNDAY EVENING AND MONDAY...PRECIPITATION TYPE WILL BE SNOW...AS ANOTHER COLD FRONT DROPS SOUTH OUT OF CANADA. FOLLOWING THE PASSAGE OF THE COLD FRONT...COLDER H850 TEMPERATURES OF -8 TO -12 C ARE POSSIBLE AT THE BEGINNING OF NEXT WEEK...AS A SURFACE HIGH PRESSURE STARTS TO MOVE SOUTH. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING... ISSUED AT 546 PM CDT MON APR 1 2013 GENERALLY CLEAR SKIES/VFR CONDITIONS WILL PREVAIL OVER WESTERN AND CENTRAL NORTH DAKOTA THROUGH THE 00Z TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...TM LONG TERM...LTH AVIATION...KS
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1113 AM MDT MON APR 1 2013 .UPDATE... ISSUED AT 1047 AM MDT MON APR 1 2013 CURRENT SURFACE ANALYSIS SHOWS CANADIAN HIGH PRESSURE OVER EASTERN PORTIONS OF THE DAKOTAS. UPPER LEVEL ANALYSIS SHOWS LARGE TROF CENTERED OVER THE GREAT LAKES REGION...WITH RIDGING OVER THE PACIFIC NW. A CUTOFF LOW IS SLOWLY MOVING EAST-SOUTHEAST ACROSS NV. SKIES CURRENTLY RANGE FROM SUNNY ACROSS NORTHEAST WY AND SOUTHWESTERN SD TO PARTLY TO MOSTLY CLOUDY FROM NORTHWESTERN INTO CENTRAL SD. BAND OF CLOUDS IS SLOWLY DISSIPATING ACROSS THESE AREAS...WITH MOSTLY SUNNY SKIES EXPECTED BY EARLY AFTERNOON. NEAR TO SLIGHTLY BELOW AVERAGE TEMPERATURES CAN BE EXPECTED THIS AFTERNOON...WITH HIGHS IN THE MID 40S TO MID 50S...WARMEST OVER NORTHEASTERN WY AND COOLEST OVER FAR EASTERN AREAS. WINDS WILL REMAIN RELATIVELY LIGHT AND VARIABLE THROUGH THE AFTERNOON. MAIN ADJUSTMENTS TO THE FORECAST WERE TO TWEAK CLOUD COVER AND WINDS FOR THE REST OF TODAY. && .SHORT TERM...TODAY THROUGH TUESDAY NIGHT ISSUED AT 240 AM MDT MON APR 1 2013 ACTIVE PROGRESSIVE NORTHERN STREAM FLOW WILL DOMINATE THE WEATHER IN THE PERIOD...WITH A LARGE SCALE SPLIT FLOW REGIME. THIS WILL OFFER WARM DOWNSLOPE PAC ORIGIN FLOW INTO THE AREA...ESP TUE. GREAT LAKES UPPER TROUGH WILL SLOWLY SHIFT EAST WITH DEEP LAYER RIDGING DEVELOPING TODAY...INITIATING WAA BY THIS AFTERNOON OVER THE WESTERN FA. THE ONLY FORECAST CONCERN TODAY WILL BE THE EVOLUTION OF THE CURRENT STRATUS IN PLACE ACROSS THE EASTERN FA...WHICH MAY HAMPER T RISES. THE ONLY FORECAST MODELS WHICH SEEMS TO HAVE ANY SORT OF HANDLE ON THE EXISTENCE OF CLOUD COVER IS THE RAP AND LOCAL WRF...WITH ALL OTHER GUIDANCE REMAINING TOO DRY IN THE LL/S. RAP/LOCAL WRF BOTH INDICATE THAT INCREASING DRY WESTERLY FLOW AT THE BL TOP SHOULD HELP ERODE CLOUD COVER WEST TO EAST THROUGH MORNING AND TRIED TO INCORPORATE THIS IDEA INTO THE GRIDS. ONCE CLOUDS CLEAR...SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE PERIOD...SAVE FOR SOME PASSING CIRRUS. TEMPS WILL REMAIN ON THE COOL SIDE ACROSS MOST OF THE AREA TODAY...WITH THE SD PLAINS BEING THE COOLEST. NE WY WILL SEE QUICK RESPONSE TO ENSUING WAA WITH MANY PLACES EXPECTED TO BE IN THE 50S THERE. HAVE ADJUSTED TEMPS UP SOME...GIVEN LATEST BLENDED GUIDANCE WITH STRONG INSOLATION EXPECTED. MUCH WARMER CONDITIONS EXPECTED TUE...WITH 50S AND 60S COMMON MOST PLACES. HAVE WARMED MOST PLACES A FEW DEGREES TUE...ESP NE WY. STRONG INSOLATION SHOULD SUPPORT SUPERADIABATS AT MOST LOCATIONS GIVEN WEAK LL FLOW...WITH TEMPS WARMER THAN CURRENT FORECAST HIGHS CERTAINLY POSSIBLE. THE NEXT NORTHERN STREAM IMPULSE WILL APPROACH THE REGION TUE...WITH WAA RAMPING UP...AS WELL AS LL SOUTHERLY FLOW TUE NIGHT. THIS SHOULD KEEP TEMPS UP AT MANY PLACES OVERNIGHT TUE...GIVEN TURBULENT MIXING...ESP IN THE LEE DOWNSLOPE AREAS OF THE BH. .LONG TERM...WEDNESDAY THROUGH SUNDAY ISSUED AT 240 AM MDT MON APR 1 2013 UPPER LEVEL RIDGE FLATTENS LATE WEDNESDAY AS A COLD FRONT CROSSES THE AREA...BRINGING A CHANCE FOR RAIN SHOWERS AND AN ISOLATED THUNDERSTORM. RAIN SHOWERS WILL LINGER INTO THURSDAY...MAINLY ACROSS NORTHERN PORTIONS OF THE AREA. A MORE UNSETTLED PATTERN WILL DEVELOP BY THE WEEKEND AS A LARGE UPPER TROF DEVELOPS OVER THE WEST COAST AND A SERIES OF DISTURBANCES MOVE ACROSS THE NORTHERN PLAINS IN WEST TO SOUTHWEST FLOW. TEMPERATURES WILL GENERALLY STAY ABOVE AVERAGE LATE IN THE WEEK AND LIKELY DROP CLOSER TO AVERAGE LEVELS DURING THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1109 AM MDT MON APR 1 2013 LEFTOVER MARGINALLY MVFR CIGS FROM KPHP TO KVTN WILL MOVE SLOWLY EAST AND DISSIPATE EARLY THIS AFTERNOON AS BOUNDARY LAYER MIXES OUT. SOME VFR CU IS EXPECTED FROM K2WX TO KVTN FOR THE AFTERNOON. OTHERWISE...VFR CONDITIONS WILL BE THE RULE THROUGH THE PERIOD. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...26 SHORT TERM...JC LONG TERM...15 AVIATION...HELGESON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1047 AM MDT MON APR 1 2013 .UPDATE... ISSUED AT 1047 AM MDT MON APR 1 2013 CURRENT SURFACE ANALYSIS SHOWS CANADIAN HIGH PRESSURE OVER EASTERN PORTIONS OF THE DAKOTAS. UPPER LEVEL ANALYSIS SHOWS LARGE TROF CENTERED OVER THE GREAT LAKES REGION...WITH RIDGING OVER THE PACIFIC NW. A CUTOFF LOW IS SLOWLY MOVING EAST-SOUTHEAST ACROSS NV. SKIES CURRENTLY RANGE FROM SUNNY ACROSS NORTHEAST WY AND SOUTHWESTERN SD TO PARTLY TO MOSTLY CLOUDY FROM NORTHWESTERN INTO CENTRAL SD. BAND OF CLOUDS IS SLOWLY DISSIPATING ACROSS THESE AREAS...WITH MOSTLY SUNNY SKIES EXPECTED BY EARLY AFTERNOON. NEAR TO SLIGHTLY BELOW AVERAGE TEMPERATURES CAN BE EXPECTED THIS AFTERNOON...WITH HIGHS IN THE MID 40S TO MID 50S...WARMEST OVER NORTHEASTERN WY AND COOLEST OVER FAR EASTERN AREAS. WINDS WILL REMAIN RELATIVELY LIGHT AND VARIABLE THROUGH THE AFTERNOON. MAIN ADJUSTMENTS TO THE FORECAST WERE TO TWEAK CLOUD COVER AND WINDS FOR THE REST OF TODAY. && .SHORT TERM...TODAY THROUGH TUESDAY NIGHT ISSUED AT 240 AM MDT MON APR 1 2013 ACTIVE PROGRESSIVE NORTHERN STREAM FLOW WILL DOMINATE THE WEATHER IN THE PERIOD...WITH A LARGE SCALE SPLIT FLOW REGIME. THIS WILL OFFER WARM DOWNSLOPE PAC ORIGIN FLOW INTO THE AREA...ESP TUE. GREAT LAKES UPPER TROUGH WILL SLOWLY SHIFT EAST WITH DEEP LAYER RIDGING DEVELOPING TODAY...INITIATING WAA BY THIS AFTERNOON OVER THE WESTERN FA. THE ONLY FORECAST CONCERN TODAY WILL BE THE EVOLUTION OF THE CURRENT STRATUS IN PLACE ACROSS THE EASTERN FA...WHICH MAY HAMPER T RISES. THE ONLY FORECAST MODELS WHICH SEEMS TO HAVE ANY SORT OF HANDLE ON THE EXISTENCE OF CLOUD COVER IS THE RAP AND LOCAL WRF...WITH ALL OTHER GUIDANCE REMAINING TOO DRY IN THE LL/S. RAP/LOCAL WRF BOTH INDICATE THAT INCREASING DRY WESTERLY FLOW AT THE BL TOP SHOULD HELP ERODE CLOUD COVER WEST TO EAST THROUGH MORNING AND TRIED TO INCORPORATE THIS IDEA INTO THE GRIDS. ONCE CLOUDS CLEAR...SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE PERIOD...SAVE FOR SOME PASSING CIRRUS. TEMPS WILL REMAIN ON THE COOL SIDE ACROSS MOST OF THE AREA TODAY...WITH THE SD PLAINS BEING THE COOLEST. NE WY WILL SEE QUICK RESPONSE TO ENSUING WAA WITH MANY PLACES EXPECTED TO BE IN THE 50S THERE. HAVE ADJUSTED TEMPS UP SOME...GIVEN LATEST BLENDED GUIDANCE WITH STRONG INSOLATION EXPECTED. MUCH WARMER CONDITIONS EXPECTED TUE...WITH 50S AND 60S COMMON MOST PLACES. HAVE WARMED MOST PLACES A FEW DEGREES TUE...ESP NE WY. STRONG INSOLATION SHOULD SUPPORT SUPERADIABATS AT MOST LOCATIONS GIVEN WEAK LL FLOW...WITH TEMPS WARMER THAN CURRENT FORECAST HIGHS CERTAINLY POSSIBLE. THE NEXT NORTHERN STREAM IMPULSE WILL APPROACH THE REGION TUE...WITH WAA RAMPING UP...AS WELL AS LL SOUTHERLY FLOW TUE NIGHT. THIS SHOULD KEEP TEMPS UP AT MANY PLACES OVERNIGHT TUE...GIVEN TURBULENT MIXING...ESP IN THE LEE DOWNSLOPE AREAS OF THE BH. .LONG TERM...WEDNESDAY THROUGH SUNDAY ISSUED AT 240 AM MDT MON APR 1 2013 UPPER LEVEL RIDGE FLATTENS LATE WEDNESDAY AS A COLD FRONT CROSSES THE AREA...BRINGING A CHANCE FOR RAIN SHOWERS AND AN ISOLATED THUNDERSTORM. RAIN SHOWERS WILL LINGER INTO THURSDAY...MAINLY ACROSS NORTHERN PORTIONS OF THE AREA. A MORE UNSETTLED PATTERN WILL DEVELOP BY THE WEEKEND AS A LARGE UPPER TROF DEVELOPS OVER THE WEST COAST AND A SERIES OF DISTURBANCES MOVE ACROSS THE NORTHERN PLAINS IN WEST TO SOUTHWEST FLOW. TEMPERATURES WILL GENERALLY STAY ABOVE AVERAGE LATE IN THE WEEK AND LIKELY DROP CLOSER TO AVERAGE LEVELS DURING THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 540 AM MDT MON APR 1 2013 MVFR CIGS WILL PERSIST ACROSS THE WESTERN SOUTH DAKOTA PLAINS THROUGH THE MORNING HOURS BEFORE LIFTING AND SHIFTING EAST BY 18Z. VFR CONDITIONS ARE THEN EXPECTED THROUGH TUESDAY MORNING. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ UPDATE...26 SHORT TERM...JC LONG TERM...15 AVIATION...15
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
541 AM MDT MON APR 1 2013 .SHORT TERM...TODAY THROUGH TUESDAY NIGHT ISSUED AT 240 AM MDT MON APR 1 2013 ACTIVE PROGRESSIVE NORTHERN STREAM FLOW WILL DOMINATE THE WEATHER IN THE PERIOD...WITH A LARGE SCALE SPLIT FLOW REGIME. THIS WILL OFFER WARM DOWNSLOPE PAC ORIGIN FLOW INTO THE AREA...ESP TUE. GREAT LAKES UPPER TROUGH WILL SLOWLY SHIFT EAST WITH DEEP LAYER RIDGING DEVELOPING TODAY...INITIATING WAA BY THIS AFTERNOON OVER THE WESTERN FA. THE ONLY FORECAST CONCERN TODAY WILL BE THE EVOLUTION OF THE CURRENT STRATUS IN PLACE ACROSS THE EASTERN FA...WHICH MAY HAMPER T RISES. THE ONLY FORECAST MODELS WHICH SEEMS TO HAVE ANY SORT OF HANDLE ON THE EXISTENCE OF CLOUD COVER IS THE RAP AND LOCAL WRF...WITH ALL OTHER GUIDANCE REMAINING TOO DRY IN THE LL/S. RAP/LOCAL WRF BOTH INDICATE THAT INCREASING DRY WESTERLY FLOW AT THE BL TOP SHOULD HELP ERODE CLOUD COVER WEST TO EAST THROUGH MORNING AND TRIED TO INCORPORATE THIS IDEA INTO THE GRIDS. ONCE CLOUDS CLEAR...SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE PERIOD...SAVE FOR SOME PASSING CIRRUS. TEMPS WILL REMAIN ON THE COOL SIDE ACROSS MOST OF THE AREA TODAY...WITH THE SD PLAINS BEING THE COOLEST. NE WY WILL SEE QUICK RESPONSE TO ENSUING WAA WITH MANY PLACES EXPECTED TO BE IN THE 50S THERE. HAVE ADJUSTED TEMPS UP SOME...GIVEN LATEST BLENDED GUIDANCE WITH STRONG INSOLATION EXPECTED. MUCH WARMER CONDITIONS EXPECTED TUE...WITH 50S AND 60S COMMON MOST PLACES. HAVE WARMED MOST PLACES A FEW DEGREES TUE...ESP NE WY. STRONG INSOLATION SHOULD SUPPORT SUPERADIABATS AT MOST LOCATIONS GIVEN WEAK LL FLOW...WITH TEMPS WARMER THAN CURRENT FORECAST HIGHS CERTAINLY POSSIBLE. THE NEXT NORTHERN STREAM IMPULSE WILL APPROACH THE REGION TUE...WITH WAA RAMPING UP...AS WELL AS LL SOUTHERLY FLOW TUE NIGHT. THIS SHOULD KEEP TEMPS UP AT MANY PLACES OVERNIGHT TUE...GIVEN TURBULENT MIXING...ESP IN THE LEE DOWNSLOPE AREAS OF THE BH. .LONG TERM...WEDNESDAY THROUGH SUNDAY ISSUED AT 240 AM MDT MON APR 1 2013 UPPER LEVEL RIDGE FLATTENS LATE WEDNESDAY AS A COLD FRONT CROSSES THE AREA...BRINGING A CHANCE FOR RAIN SHOWERS AND AN ISOLATED THUNDERSTORM. RAIN SHOWERS WILL LINGER INTO THURSDAY...MAINLY ACROSS NORTHERN PORTIONS OF THE AREA. A MORE UNSETTLED PATTERN WILL DEVELOP BY THE WEEKEND AS A LARGE UPPER TROF DEVELOPS OVER THE WEST COAST AND A SERIES OF DISTURBANCES MOVE ACROSS THE NORTHERN PLAINS IN WEST TO SOUTHWEST FLOW. TEMPERATURES WILL GENERALLY STAY ABOVE AVERAGE LATE IN THE WEEK AND LIKELY DROP CLOSER TO AVERAGE LEVELS DURING THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 540 AM MDT MON APR 1 2013 MVFR CIGS WILL PERSIST ACROSS THE WESTERN SOUTH DAKOTA PLAINS THROUGH THE MORNING HOURS BEFORE LIFTING AND SHIFTING EAST BY 18Z. VFR CONDITIONS ARE THEN EXPECTED THROUGH TUESDAY MORNING. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...JC LONG TERM...15 AVIATION...15
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
241 AM MDT MON APR 1 2013 .SHORT TERM...TODAY THROUGH TUESDAY NIGHT ISSUED AT 240 AM MDT MON APR 1 2013 ACTIVE PROGRESSIVE NORTHERN STREAM FLOW WILL DOMINATE THE WEATHER IN THE PERIOD...WITH A LARGE SCALE SPLIT FLOW REGIME. THIS WILL OFFER WARM DOWNSLOPE PAC ORIGIN FLOW INTO THE AREA...ESP TUE. GREAT LAKES UPPER TROUGH WILL SLOWLY SHIFT EAST WITH DEEP LAYER RIDGING DEVELOPING TODAY...INITIATING WAA BY THIS AFTERNOON OVER THE WESTERN FA. THE ONLY FORECAST CONCERN TODAY WILL BE THE EVOLUTION OF THE CURRENT STRATUS IN PLACE ACROSS THE EASTERN FA...WHICH MAY HAMPER T RISES. THE ONLY FORECAST MODELS WHICH SEEMS TO HAVE ANY SORT OF HANDLE ON THE EXISTENCE OF CLOUD COVER IS THE RAP AND LOCAL WRF...WITH ALL OTHER GUIDANCE REMAINING TOO DRY IN THE LL/S. RAP/LOCAL WRF BOTH INDICATE THAT INCREASING DRY WESTERLY FLOW AT THE BL TOP SHOULD HELP ERODE CLOUD COVER WEST TO EAST THROUGH MORNING AND TRIED TO INCORPORATE THIS IDEA INTO THE GRIDS. ONCE CLOUDS CLEAR...SKIES WILL REMAIN MOSTLY CLEAR THROUGH THE PERIOD...SAVE FOR SOME PASSING CIRRUS. TEMPS WILL REMAIN ON THE COOL SIDE ACROSS MOST OF THE AREA TODAY...WITH THE SD PLAINS BEING THE COOLEST. NE WY WILL SEE QUICK RESPONSE TO ENSUING WAA WITH MANY PLACES EXPECTED TO BE IN THE 50S THERE. HAVE ADJUSTED TEMPS UP SOME...GIVEN LATEST BLENDED GUIDANCE WITH STRONG INSOLATION EXPECTED. MUCH WARMER CONDITIONS EXPECTED TUE...WITH 50S AND 60S COMMON MOST PLACES. HAVE WARMED MOST PLACES A FEW DEGREES TUE...ESP NE WY. STRONG INSOLATION SHOULD SUPPORT SUPERADIABATS AT MOST LOCATIONS GIVEN WEAK LL FLOW...WITH TEMPS WARMER THAN CURRENT FORECAST HIGHS CERTAINLY POSSIBLE. THE NEXT NORTHERN STREAM IMPULSE WILL APPROACH THE REGION TUE...WITH WAA RAMPING UP...AS WELL AS LL SOUTHERLY FLOW TUE NIGHT. THIS SHOULD KEEP TEMPS UP AT MANY PLACES OVERNIGHT TUE...GIVEN TURBULENT MIXING...ESP IN THE LEE DOWNSLOPE AREAS OF THE BH. && .LONG TERM...WEDNESDAY THROUGH SUNDAY ISSUED AT 240 AM MDT MON APR 1 2013 UPPER LEVEL RIDGE FLATTENS LATE WEDNESDAY AS A COLD FRONT CROSSES THE AREA...BRINGING A CHANCE FOR RAIN SHOWERS AND AN ISOLATED THUNDERSTORM. RAIN SHOWERS WILL LINGER INTO THURSDAY...MAINLY ACROSS NORTHERN PORTIONS OF THE AREA. A MORE UNSETTLED PATTERN WILL DEVELOP BY THE WEEKEND AS A LARGE UPPER TROF DEVELOPS OVER THE WEST COAST AND A SERIES OF DISTURBANCES MOVE ACROSS THE NORTHERN PLAINS IN WEST TO SOUTHWEST FLOW. TEMPERATURES WILL GENERALLY STAY ABOVE AVERAGE LATE IN THE WEEK AND LIKELY DROP CLOSER TO AVERAGE LEVELS DURING THE WEEKEND. && .AVIATION...FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT ISSUED AT 240 AM MDT MON APR 1 2013 MVFR AND LOCAL IFR CIGS WILL PERSIST ACROSS WESTERN SOUTH DAKOTA THROUGH THE MORNING HOURS BEFORE LIFTING AND SHIFTING EAST BY 18Z. VFR CONDITIONS ARE THEN EXPECTED THROUGH TUESDAY MORNING. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && $$ SHORT TERM...JC LONG TERM...15 AVIATION...15
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
329 PM CDT MON APR 1 2013 .SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)...ANOTHER ONE OF THESE FORECASTS WHERE MESO-SCALE INFLUENCES MAY PLAY HAVOC ON WHAT TRANSPIRES TONIGHT. MAIN FLY IN OINTMENT NOW IS THAT LOTS OF STRATUS IS JUST ACROSS THE RIVER AND TEMPERATURES OUT WEST ARE NOT THAT WARM...SO SEA BREEZE LIMITED OUT THERE AS WELL AS DAYTIME HEATING. THUS...CONVERGING BOUNDARIES LIKE LAST NIGHT NOT PRESENT AND STORMS MAY HAVE A HARD TIME FIRING UP DIRECTLY WEST OF FORECAST AREA. HOWEVER...STORMS ARE DEVELOPING FARTHER NORTHWEST OF STRATUS DECK (HAVE A LONG WAY TO GO THOUGH). STILL AM GOING TO GO WITH LOW CHANCE POPS NEAR RIO GRANDE AND DIMINISH THEM FARTHER EAST. THING THAT HELPS CONVECTION TO DEVELOP IS EASTERLY UPSLOPE FLOW SO DO NOT WANT TO GO TOO LOW ON POPS (ESPECIALLY WITH SLIGHT RISK IN AREA)...AND WITH SPC 4 KM MODEL AND HRRR MODEL SHOWING ACTIVITY MOVING IN THERE. OTHERWISE...TEMPERATURES SHOULD BE SIMILAR TO LAST NIGHT...EXCEPT WHERE CONVECTION COULD COOL AIR SOME. NO SIGNIFICANT FOG EXPECTED. UPPER LEVEL JET IMPACTS AREA ON TUESDAY AS CAP BREAKS/WEAKENS. AM GOING HIGH CHANCE POPS EASTERN AREAS...TAD LOWER OUT WEST. MORE CLOUDS AND RAIN-COOLED AIR MEANS LOWER TEMPERATURES TUESDAY. SOME JET DYNAMICS REMAIN TUESDAY NIGHT AS FRONT APPROACHES...SO PRETTY MUCH HAVE KEPT POPS SIMILAR TO PREVIOUS FORECAST WITH SLIGHT ADJUSTMENT OF HIGHER POPS A BIT MORE TOWARD THE NORTHEAST (AREA ADJUSTEMENT...STILL NO MORE THAN 70 POPS). WITH COOLER AIR REMAINING NORTH OF AREA (BUT PROBABLY SOME CONVECTION AROUND COOLING THINGS OFF)...WILL GO A BIT COOLER TUESDAY NIGHT THAN TONIGHT. SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO HIGHLIGHT UPCOMING EVENT. && .MARINE (TONIGHT THROUGH TUESDAY NIGHT)...SEA FOG ALBEIT LIGHT REMAINS IN THE FORECAST AS VISIBLE SATELLITE AND OBSERVATIONS SHOW SOME OUT THERE. OVERALL VISIBILITIES SHOULD REMAIN ABOVE 2 NM. GENERALLY WEAK TO MODERATE ESE/SE FLOW THROUGH THE PERIOD. RAIN CHANCES INCREASE MAINLY LATE TUESDAY AND TUESDAY NIGHT. && .LONG TERM (WEDNESDAY THROUGH SUNDAY)...OVERALL TREND CONTINUES ABUNDANT GULF MOISTURE ACROSS THE REGION WITH PWATS 1.3 TO 1.5 INCHES...WHICH IS JUST OVER 75 PERCENT OF NORMAL PWATS FOR THIS TIME OF YEAR. TIMING OF THE FRONT STILL REMAINS A CHALLENGE ALTHOUGH MODEST AGREEMENT BETWEEN THE EURO/CANADIAN/NAM AROUND 00Z...WITH THE GFS LAGGING A FEW HOURS BEHIND. A PREFRONTAL WIND SHIFT SHOULD TAKE PLACE BETWEEN 18Z-00Z. WITH MULTIPLE SHORTWAVES ROUNDING THE SOUTHERN PERIPHERY OF THE MIDLEVEL LOW //POSITIONED OVER THE CENTRAL PLAINS//...CONTINUED HIGH END CHANCE TO LIKELY POPS GOING INTO WEDNESDAY...WITH MOST ACTIVITY IN THE MORNING BEING MORE OF A SHOWER ACTIVITY UNDER A WEAK CAP. HOWEVER...DID CONTINUE THUNDER WORDING AS A VORT MAX AND 60 KNOT JET MOVE OVER THE AREA. DID SHOW THE INCREASE IN CHANCES INTO THE AFTERNOON AS FURTHER COOLING IN THE MIDLEVELS TAKES PLACE WITH THE FRONT SLOWLY MOVING SOUTHWARD. CONCERN DOES EXIST IN THE AFTERNOON TO EARLY EVENING FOR STRONG TO SEVERE AS LAPSE RATES STEEPEN WITH LI VALUES OF -7C TO -9C. HOWEVER...THE ONSHORE IS WEAK TO FEED INTO ANY STORMS. CURRENTLY IF ANYTHING DEVELOPS INTO THE STRONG TO SEVERE CATEGORY...SHOULD BE MORE OF PULSE STORMS...WITH BETTER CHANCES ALONG THE FRONT ITSELF. WILL CONTINUE TO MONITOR THE DEVELOPMENT OF THIS WEATHER EVENT. MOISTURE AND THE MIDLEVEL LOW PULLS TO THE NORTHEAST WITH DRYING FROM WEST TO EAST LATE WEDNESDAY INTO THURSDAY WITH HIGH PRESSURE ENTERING THE REGION. QUIET WEATHER TO PERSIST INTO THE WEEKEND WITH A ONSHORE FLOW DEVELOPING SATURDAY. TEMPERATURES TO COOL INTO THE 70S AREAWIDE THURSDAY...WITH A WARMING TREND INTO THE WEEKEND UNDER MOSTLY CLEAR TO PARTLY CLOUDY SKIES. && .PRELIMINARY POINT TEMPS/POPS... CORPUS CHRISTI 68 82 69 81 55 / 10 50 50 70 40 VICTORIA 66 80 66 76 52 / 10 50 70 70 40 LAREDO 67 86 70 83 58 / 40 30 30 40 10 ALICE 68 86 69 83 55 / 10 50 50 60 30 ROCKPORT 68 77 68 75 55 / 10 50 60 70 40 COTULLA 65 83 67 78 53 / 30 30 50 50 10 KINGSVILLE 67 84 69 82 55 / 10 50 40 60 40 NAVY CORPUS 68 78 69 76 58 / 10 50 50 70 40 && .CRP WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ GW/86...SHORT TERM CB/85...LONG TERM
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
208 PM CDT MON APR 1 2013 .SHORT TERM /NOW THROUGH TUESDAY NIGHT/...THE AREA REMAINS IN QUASI-ZONAL FLOW ALOFT WITH AN UPPER LEVEL TROUGH LOCATED OVER THE GREAT BASIN AND A WEAK IMPULSE RIDING WESTERLY FLOW IN NORTHERN MEXICO SOUTH OF THE TEXAS BIG BEND. AT THE SURFACE...SOUTHEASTERLY FLOW CONTINUES TO ADVECT MOISTURE FROM THE GULF OF MEXICO WITH A COLD FRONT LOCATED ACROSS OKLAHOMA AND THE TEXAS PANHANDLE. A 1020MB HIGH IS LOCATED ACROSS THE ARKLAMISS. FOR THE REST OF THE AFTERNOON AND INTO THIS EVENING...WILL CONTINUE TO SEE CLOUDS BREAK UP AS MIXING AND DAYTIME HEATING CONTINUES. THICKER STRATOCU RESIDES OVER ZAPATA/JIM HOGG/STARR COUNTIES AND MAY BE A LITTLE HARDER TO BREAK UP CLOUDS IN THIS AREA. EVEN THOUGH THICK CLOUDS ARE LOCATED HERE...TEMPERATURES HAVE WARMED NICELY AND ARE ACTUALLY ABOVE FORECASTED HOURLY TEMPERATURES BUT LOOK GOOD FOR THE HIGHS THIS AFTERNOON. WEAK IMPULSE TO OUR WEST IS FORECAST TO SPARK CONVECTION ON THE SIERRA MADRE LATER THIS AFTERNOON AS IT MOVES EAST. LATEST HRRR AND SPC 4KM WRF CONTINUE TO ROLL CONVECTION OFF THE HIGHER TERRAIN AND MAKE A RUN AT OUR WESTERN ZONES. CURRENT 20 POPS OUT WEST LOOK GOOD FOR THIS EVENING AND MADE ONLY MINOR ADJUSTMENTS TO MOVE JUST A LITTLE EASTWARD. ANY STORMS THAT DO CREEP INTO OUR AREA WILL QUICKLY DISSIPATE TOWARDS MID EVENING AS BOUNDARY LEVEL STABILIZES. FOR TONIGHT...LOW CLOUDS WILL MOVE BACK IN ON SOUTHEASTERLY LOW LEVEL WINDS BY MID TO LATE EVENING. NAM12/RAP/HRRR SHOW SIGNALS OF SEA FOG DEVELOPING AND/OR ADVECTING IN TO THE COASTAL AREAS OVERNIGHT. ADDED AREAS OF FOG ALONG THE COASTLINE WITH PATCHY FOG INLAND. WILL HOLD OFF ON ANY DENSE FOG ADVISORY AT THIS TIME AND LET SWING SHIFT MAKE THE CALL. INCREASED LOW TEMPERATURES SLIGHTLY WITH EXPECTED ABUNDANCE OF LOW CLOUDS AND LOOKING AT MAINLY UPPER 60S TO LOWER 70S. FOR TUESDAY...WE WILL START OUT WITH THOSE LOW CLOUDS AND WILL BREAK OUT AND DISSIPATE BY LATE MORNING. MIXING WILL TAKE PLACE BY MID MORNING WITH GUSTY WINDS BY LATE MORNING. ANOTHER IMPULSE IS PROGGED TO MOVE ACROSS THE AREA EARLY TUESDAY AFTERNOON. THERE IS PLACEMENT ISSUES BETWEEN THE NAM AND GFS WITH THE NAM FURTHER NORTH AND THE GFS IS ACROSS THE NORTHERN PORTION OF THE AREA AND IS WEAKER THAN THE PREVIOUS RUN. KEPT POPS AS IS AND JUST TWEAKED LOCATION BASED ON 12Z GFS. A STRONG TO SEVERE STORM IS POSSIBLE GIVEN THE THERMODYNAMIC ENVIRONMENT. FOR TUESDAY NIGHT...THAT IMPULSE IS WELL NORTH OF THE AREA WITH JUST A FEW SHOWERS LEFT OVER IN THE COASTAL WATERS. ATMOSPHERE WILL STABILIZE RATHER RAPIDLY AFTER SUNSET WITH SKIES BECOMING CLOUDY ONCE AGAIN. COLD FRONT WILL SAG INTO NORTH CENTRAL TEXAS WITH A SFC LOW SOUTH OF THE TEXAS BIG BEND. CLOUDS WILL KEEP LOWS UP...COMPARABLE TO TONIGHT. .LONG TERM /WEDNESDAY THROUGH MONDAY/...12Z MODEL RUN REMAINS PERSISTENT ON THE TRACK AND STRENGTH OF THE MID TO UPPER LEVEL TROUGH CURRENTLY OVER THE GREAT BASIN. BY 18Z WEDNESDAY GFS PLACES THE UPPER TROUGH AXIS ACROSS NORTHWEST TEXAS AROUND 18Z WITH ITS ASSOCIATED COLD FRONT APPROACHING THE NORTHERN PORTIONS OF THE CWA. LARGE SCALE ASCENT COUPLED WITH LOW LEVEL CONVERGENCE ALONG THE FRONT SHOULD BE THE COMBINATION NEEDED TO BRING ABOUT THE CHANCE OF RAIN WE HAVE SEEN IN A WHILE. MODEST LOW LEVEL MOISTURE WILL BE IN PLACE AND A LATE AFTERNOON FRONTAL PASSAGE SHOULD ALLOW FOR SURFACE HEATING TO EXCEED GUIDANCE VALUES. SPC MAINTAINS GENERAL THUNDERSTORM CHANCES FOR WEDNESDAY BUT CAN NOT RULE OUT ISOLATED SEVERE STORMS AS THE ATMOSPHERE BECOMES INCREASINGLY UNSTABLE. A DAY TO DAY ANALYSIS TO TAKE PLACE BEFORE WE ADD SEVERE WORDING INTO THE FORECAST/GRIDS. POP GUIDANCE REMAINS AT LOW END CHANCE BUT THIS MIGHT BE ON THE LOW END WITH DYNAMICS LOOKING A BETTER THEN YESTERDAY AT THIS TIME. KEEP WED AND WEDNESDAY NIGHT POPS CLOSE TO THE PREVIOUS FORECAST. AS MENTIONED TEMPERATURES SHOULD CLIMB AHEAD OF THE COLD FRONT WITH A LATE AFTERNOON OR EARLY EVENING PASSAGE. FORECAST HIGHS TO REMAIN ABOVE GUIDANCE VALUES ESPECIALLY IF WE SEE MORE SUN PEAK THROUGH. TROUGH AXIS AND SURFACE LOW PRESSURE QUICKLY EXITS TO THE EAST THURSDAY MORNING. HUNG ON TO LOW POPS ACROSS THE COASTAL COUNTIES BEFORE ENDING THURSDAY AFTERNOON AS THIS SYSTEM OPENS AND PUSHES TO THE EAST. FAIR WEATHER ENSUES THURSDAY AFTERNOON INTO FRIDAY AS SHORTWAVE RIDGING BUILDS OVERHEAD. COOL TO MILD TEMPERATURES THURSDAY MORNING WITH SOME RECOVERY THURSDAY WITH HIGHS DROPPING TO SLIGHTLY EARLY APRIL NORMALS. GFS HAS BEEN INDICATING A QUICK RETURN OF GULF MOISTURE FRIDAY NIGHT INTO SATURDAY. A WEAK DISTURBANCE IN THE ZONAL FLOW HAS BEEN SEEN THE LAST FEW RUNS. ALTHOUGH GUIDANCE IS SHOWING VERY LOW POPS ON SATURDAY WILL UP THE CHANCES SLIGHTLY TO MENTION ISOLATED SHOWERS. MODEST DIVERGENCE AND SUFFICIENT MOISTURE...IF OCCURS MIGHT BE ENOUGH FOR A FEW SHOWERS. WIND MACHINE TO POSSIBLY TURN ON SUNDAY AND MONDAY AS NEXT TROUGH AND SURFACE LOW DEVELOP OUT WEST. TEMPERATURES TO CLIMB AS USUAL. && .MARINE /NOW THROUGH TUESDAY/GENERALLY FAVORABLE MARINE CONDITIONS ARE EXPECTED THROUGH TUESDAY NIGHT WITH MODERATE EASTERLY TO SOUTHEASTERLY WINDS. CONDITIONS MAY APPROACH EXERCISE CAUTION LEVELS ON THE GULF OF MEXICO TONIGHT. SEAS SHOULD REMAIN LOW TO MODERATE. WEDNESDAY THROUGH SUNDAY...COLD FRONT ON TAP FOR A LATE WEDNESDAY OR WEDNESDAY EVENING PASSAGE. LIGHT WINDS IN ADVANCE OF THE FRONT TO SHIFT AND INCREASE FROM THE NORTH. SMALL CRAFT ADVISORIES STILL EXPECTED WITH A 6 TO 12 HOUR WINDOW OF STRONG NORTH FLOW WEDNESDAY NIGHT INTO EARLY THURSDAY AS SURFACE LOW PRESSURE DEVELOPS EAST OF PADRE ISLAND ALONG THE FRONT. WITH THE SURFACE LOW TRACKING EAST FAIRLY QUICKLY THURSDAY NORTH TO NORTHEAST WINDS TO WEAKEN. WINDS VEER FRIDAY TO THE EAST AND SOUTHEAST BY FRIDAY NIGHT BUT THE RETURN FLOW REMAINS LIGHT TO MODERATE. MORE SUBSTANTIAL INCREASE OF SOUTHEAST WINDS RESUME SUNDAY INTO MONDAY AS THE GRADIENT TIGHTENS WITH LOW PRESSURE DEEPENING ACROSS WESTERN TEXAS AND NORTHEAST MEXICO. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 70 82 68 82 / 10 20 30 40 BROWNSVILLE 69 84 68 84 / 10 20 30 40 HARLINGEN 70 86 68 84 / 10 20 20 40 MCALLEN 70 87 70 86 / 10 30 20 40 RIO GRANDE CITY 70 90 70 87 / 20 30 20 30 SOUTH PADRE ISLAND 69 76 68 78 / 10 20 30 40 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 55...SHORT TERM 59...LONG TERM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
311 AM CDT MON APR 1 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 311 AM CDT MON APR 1 2013 A BROAD/DEEP MID TO UPPER LEVEL TROUGH HAS SET UP ACROSS SOUTHEASTERN CANADA WHILE AN AMPLIFYING RIDGE DEVELOPS ACROSS THE WESTERN US. AT THE SURFACE...CYCLONIC FLOW PERSISTS ACROSS THE GREAT LAKES AND UPPER MISSISSIPPI RIVER VALLEY AS A RIDGE OF HIGH PRESSURE PUSHES DOWN TO THE SOUTHEAST ACROSS THE DAKOTAS. SKIES HAVE MAINLY CLEARED OUT THOUGH A FEW CU STREAKS HAVE STUCK AROUND NORTHERN WISCONSIN. SHOULD NOT SEE MUCH IN THE WAY OF CHANGES IN THE PATTERN FOR TODAY AS THE RIDGE UNDERCUTS THE REGION TO THE SOUTHWEST AND STRONGLY SUBSIDENT AIR SHOULD KEEP SKIES MAINLY CLEAR. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 311 AM CDT MON APR 1 2013 WITH 850MB TEMPERATURES STAYING BETWEEN -10C TO -15C INTO WEDNESDAY MORNING...TEMPERATURES WILL STAY WELL BELOW NORMAL OVER THIS PERIOD. THE COLDEST MORNING WILL LIKELY BE ON WEDNESDAY MORNING AS THE CORE OF THE RIDGE MOVES OVERHEAD AND ALLOWS FOR IDEAL RADIATIONAL COOLING WITH CLEAR SKIES AND LIGHT WINDS. THINK THAT SOME OF THE MODELS ARE LEANING TOWARD CLIMO AND HAVE SOME HIGHER VALUES IN THERE...SO HAVE UNDERCUT LOWS THERE A BIT FOR WEDNESDAY MORNING. TEMPERATURES WILL BE ON THE INCREASE ON WEDNESDAY AS THE RIDGE AXIS MOVES IN FROM THE WEST AND 850MB TEMPERATURES IMPROVE TO AROUND -2C TO 0C. HIGH TEMPERATURES WILL STILL BE BELOW NORMAL BUT AT LEAST WILL BE TRENDING IN THE RIGHT DIRECTION. A MID LEVEL TROUGH WILL THEN TRACK ACROSS SOUTHERN CANADA WEDNESDAY NIGHT INTO THURSDAY AND IN TURN BRING A SURFACE LOW ALONG WITH IT. A COLD FRONT WILL EXTEND SOUTH OF THIS LOW AND WILL APPROACH CENTRAL MINNESOTA/NORTHERN WISCONSIN EARLY THURSDAY MORNING. THE BETTER LIFT/MOISTURE CONVERGENCE STILL APPEARS TO BE OFF TO THE NORTHEAST CLOSER TO THE MID LEVEL/SURFACE LOW...SO IT DOES NOT LOOK LIKE THERE SHOULD BE MUCH PRECIPITATION THAT OCCURS ALONG/AHEAD OF THE COLD FRONT. THERMAL PROFILES OFF OF THE 01.00Z GFS SUGGEST THAT THE PRECIPITATION SHOULD MAINLY FALL AS LIGHT RAIN...BUT CAN NOT RULE OUT THAT THERE COULD BE SOME SNOW THAT MIXES IN AS THE PROFILE SATURATES DOWN TO THE WET BULB TEMPERATURE. THE FOCUS THEN GOES TO A MORE POTENT SYSTEM THAT WILL BE DEVELOPING IN THE CENTRAL PLAINS ON FRIDAY WITH THE AFOREMENTIONED COLD FRONT TRANSITIONING TO A WARM FRONT. THE INITIAL QUESTION REMAINS WITH HOW FAR NORTH THAT FRONT MAKES IT NEXT WEEKEND AS TEMPERATURES WILL LIKELY BE IN THE 60S TO THE SOUTH OF IT AND IN THE 30S WITH SNOW TO THE NORTH OF IT. THE ECMWF HAS FLIP FLOPPED AROUND A BIT THE PAST FEW DAYS WITH THE TRACK OF THE SURFACE LOW THAT EVENTUALLY COMES THROUGH THE REGION ON SUNDAY WHILE THE GFS HAS BEEN FAIRLY STEADY WITH ITS TRACK. A FEW OF THE ECMWF RUNS HAVE TAKEN A MORE NORTHERLY TRACK THROUGH SOUTHERN MINNESOTA/CENTRAL WISCONSIN WHILE THE GFS HAS BEEN FAIRLY CONSISTENT WITH TAKING THE LOW THROUGH IOWA. PRECIPITATION WILL INITIALLY START OUT WELL AHEAD OF THIS LOW AS WARM AIR ADVECTION/FRONTOGENESIS STRENGTHENS ALONG THE THERMAL GRADIENT. A LOT OF DETAILS TO BE WORKED OUT AND HAVE BASICALLY DONE A BLEND BETWEEN THE 01.00Z GFS/ECMWF WITH THIS SYSTEM BUT SOME DRASTIC CHANGES COULD BE IN STORE DEPENDING ON WHETHER WE END UP IN THE WARM OR COLD SECTOR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) 1148 PM CDT SUN MAR 31 2013 SURFACE HIGH PRESSURE WILL BUILD SOUTHEAST FROM THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY THROUGH THE TAF PERIOD. NORTHWEST WINDS WILL CONTINUE INTO THE 10 TO 15 KNOT RANGE THROUGH 00Z TUESDAY...THEN DIMINISH AS THE SURFACE HIGH SPREADS EASTWARD INTO THE AREA. SOME PATCHES OF MVFR CLOUDS SEEN ON SATELLITE ACROSS NORTHERN MINNESOTA. MODELS...ESPECIALLY THE NAM AND RAP ARE BOTH OVERDOING THE CURRENT MOISTURE FIELD. DID MENTION SCATTERED CLOUDS WITH BASES BETWEEN 020-030K FEET AFTER 11Z AT KRST AND 15Z AT KLSE. THIS WILL THEN DISSIPATE AFTER 00Z TUESDAY. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...HALBACH LONG TERM...HALBACH AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1148 PM CDT SUN MAR 31 2013 .SHORT TERM...TONIGHT THROUGH WEDNESDAY 321 PM CDT SUN MAR 31 2013 AT 3 PM...A CANADIAN COLD FRONT EXTENDED FROM TRAVERSE CITY MICHIGAN TO COLUMBIA MISSOURI. ANOTHER MUCH STRONGER CANADIAN COLD FRONT EXTENDED FROM IRONWOOD MICHIGAN TO MANKATO MINNESOTA. SCATTERED RAIN AND SNOW SHOWERS WERE DEVELOPING AHEAD OF THIS SECOND FRONT ACROSS WESTERN WISCONSIN. WITH 925-800 MB LAPSE RATES RUNNING AROUND 8C/KM... THE STRONGER WINDS FROM ALOFT ARE MIXING DOWN TO THE SURFACE. JUST IN THE PAST HOUR...THE WINDS HAVE BEEN GUSTING INTO THE 30 TO 35 MPH RANGE ACROSS NORTHEAST IOWA AND SOUTHEAST MINNESOTA. THE STRONGEST WIND GUST /36 MPH/ WAS A MAYO HELIPAD IN ROCHESTER MINNESOTA. THESE WIND GUST WILL QUICKLY WANE EARLY THIS EVENING WITH THE LOSS OF DIURNAL HEATING. FOR LATE TONIGHT AND MONDAY...THE 31.12Z NAM/WRF SHOWS THAT SOME OF THE CLOUDS ACROSS NORTHERN MINNESOTA...WESTERN ONTARIO...AND EASTERN MANITOBA WILL MOVE SOUTHEAST TOWARD THE FORECAST AREA. IN ADDITION WITH CONVECTIVE TEMPERATURE IN THE MID TO UPPER 20S...THIS WOULD ALSO FAVOR THE DEVELOPMENT OF A SCATTERED TO BROKEN DECK OF CUMULUS CLOUDS. IN ADDITION...THE 31.12Z NMM WOULD SUGGEST THE POSSIBILITY OF A FEW SNOW SHOWERS ACROSS TAYLOR COUNTY AND THE NORTHERN PORTIONS OF CLARK COUNTY IN CENTRAL AND NORTH CENTRAL WISCONSIN. SINCE THIS IS THE ONLY MODEL SHOWING THIS...KEPT THE FORECAST DRY FOR NOW. ON TUESDAY AFTERNOON...THE MODELS CONTINUE TO SHOW THAT ANOTHER SHORT WAVE TROUGH MOVE THROUGH THE NORTHERN AND EASTERN PORTIONS OF WISCONSIN. THE SOUNDINGS SHOW A SLIGHT SATURATION OCCURRING BETWEEN 850 AND 700 MB. WITH THE 270-280K ISENTROPIC CONDENSATION PRESSURE DEFICITS GREATER THAN 100 MB NOT EXPECTING VERY MANY CLOUDS OR PRECIPITATION FROM THIS SYSTEM. ON WEDNESDAY...THE MODELS CONTINUE TO SLOW THE EASTWARD PROGRESSION OF A FRONT MOVING TOWARD THE AREA FROM THE NORTHERN PLAINS. DUE TO THIS...THE PRESSURE GRADIENT IS NOT AS TIGHT AND THE AREA DOES NOT MIX AS DEEP. AS RESULT...COOLED THE HIGH TEMPERATURES A FEW DEGREES. .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY 321 PM CDT SUN MAR 31 2013 ON THURSDAY...A FRONT WILL MOVE THROUGH THE AREA. IT CONTINUES TO LOOK LIKE THE BEST SYNOPTIC AND ISENTROPIC LIFT AND THE BEST 925 TO 850 MB MOISTURE TRANSPORT WILL BE MAINLY TO OUR NORTHWEST. THE GFS CONTINUES TO SHOW THAT THIS FRONT WILL PRODUCE A BAND OF PRECIPITATION AS IT PROGRESSES SOUTHEAST ACROSS THE AREA. MEANWHILE THE GEM AND ECMWF SHOW THAT THIS PRECIPITATION WILL DEVELOP NORTH OF INTERSTATE 94 DURING THE MORNING AND THEN MOVES THROUGH THE REMAINDER OF THE AREA DRY DURING THE AFTERNOON. OVERALL PREFER THE ECMWF AND GEM SOLUTIONS DUE TO THE LACK OF MOISTURE TRANSPORT DURING THE AFTERNOON...AND THAT THE GFS HAS BEEN HAVING A LOT OF ISSUES WITH ITS LOW LEVEL MOISTURE DURING THE PAST MONTH. FROM FRIDAY AFTERNOON THROUGH THE UPCOMING WEEKEND...THE MODELS CONTINUE TO STRUGGLE WITH THEIR TIMING AND LOCATION OF A SERIES OF LOW PRESSURE SYSTEMS MOVING THROUGH THE REGION. MUCH OF THIS IS HOW THEY HAVE BEEN TRYING TO DEVELOP A TROUGH OVER THE WESTERN UNITED STATES AND A RIDGE OVER THE CENTRAL UNITED STATES. OVER THE PAST DAY...THE MODELS HAVE BEEN SLOWING THIS DEVELOPMENT AND THIS HAS KEPT OUR AREA MORE IN ZONAL FLOW ALOFT. AS A RESULT...THE TEMPERATURES HAVE BEEN COOLING OVER THE PAST 4 MODEL RUNS. AS A RESULT...HAD TO INTRODUCE MORE SNOW INTO THE FORECAST FOR THIS TIME PERIOD. WITH THE FIRST SYSTEM /FRIDAY AFTERNOON THROUGH SATURDAY/...THE GFS IS PRODUCING A 6 TO 12 INCH BAND OF SNOW ALONG AND NORTH OF INTERSTATE 94. MEANWHILE THE ECMWF HAS A 3 TO 6 INCH BAND OF SNOW ACROSS FAR NORTHERN WISCONSIN AND UPPER MICHIGAN. THE GFS THEN MOVES YET ANOTHER LOW PRESSURE SYSTEM INTO SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN ON SATURDAY. THE ECMWF ALSO SHOWS ANOTHER LOW PRESSURE SYSTEM...BUT IT DOES NOT AFFECT THE AREA UNTIL MONDAY. THE TEMPERATURES ALOFT LOOK A BIT WARMER...SO THE PRECIPITATION WITH THIS SYSTEM LOOKS TO BE IN THE FORM OF RAIN. && .AVIATION...THROUGH 06Z TUESDAY 1148 PM CDT SUN MAR 31 2013 SURFACE HIGH PRESSURE WILL BUILD SOUTHEAST FROM THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY THROUGH THE TAF PERIOD. NORTHWEST WINDS WILL CONTINUE INTO THE 10 TO 15 KNOT RANGE THROUGH 00Z TUESDAY...THEN DIMINISH AS THE SURFACE HIGH SPREADS EASTWARD INTO THE AREA. SOME PATCHES OF MVFR CLOUDS SEEN ON SATELLITE ACROSS NORTHERN MINNESOTA. MODELS...ESPECIALLY THE NAM AND RAP ARE BOTH OVERDOING THE CURRENT MOISTURE FIELD. DID MENTION SCATTERED CLOUDS WITH BASES BETWEEN 020-030K FEET AFTER 11Z AT KRST AND 15Z AT KLSE. THIS WILL THEN DISSIPATE AFTER 00Z TUESDAY. && .HYDROLOGY...TODAY AND TONIGHT 1235 PM CDT SUN MAR 31 2013 MANY RIVERS HAVE CLIMBED OVER THE PAST FEW DAYS DUE TO RECENT SNOW MELT AND THE RAIN THAT FELL ON SATURDAY WHICH GENERALLY TOTALED UP TO BETWEEN A QUARTER AND THREE QUARTERS OF AN INCH. THERE HAVE BEEN REPORTS OF SOME ROADS BEING CLOSED DUE TO HIGH WATER... PARTICULARLY IN PORTIONS OF SOUTHEAST MINNESOTA WHERE THERE HAD BEEN QUITE A BIT OF SNOW STILL ON THE GROUND LEADING UP TO THIS WEEKEND. APPEARS THAT HIGH WATER LEVELS ARE PAST THEIR PEAKS OVER NORTHEAST IA AND SOUTHWEST WI...AND ARE RIGHT AROUND THEIR PEAK NOW FOR SOUTHEAST MN. WITH THE COOLER WEATHER MOVING IN... ANTICIPATE THAT THE RUNOFF WILL SLOW AND CEASE...ALLOWING THIS WATER TO MOVE OFF DOWNSTREAM. WILL CONTINUE TO MONITOR THE RIVERS CLOSELY. REFER TO THE LATEST STATEMENTS FOR UP-TO-DATE INFO. && .ARX WATCHES/WARNINGS/ADVISORIES... 321 PM CDT SUN MAR 31 2013 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...RABERDING HYDROLOGY....MW
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
314 AM CDT WED APR 3 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CDT WED APR 3 2013 THE RAP...NAM AND GFS ARE SUGGESTING SUFFICIENT LOW AND MID LEVEL CLOUDINESS ACROSS SRN NEB TO HOLD TEMPS IN THE 50S TODAY. AT THE SAME TIME SOUTH AND SOUTHWEST WINDS WILL RECIRCULATE COOL AIR NORTH FROM THE HIGH PRESSURE SYSTEM ACROSS THE MID SOUTH. SO THE RAP 21Z TEMPS WERE USED AS THE BASIS FOR TODAYS HIGHS WHICH IS CLOSE TO THE GUIDANCE DATA SETS. IF FULL SUN ARRIVES OR EVEN JUST HIGH LEVEL CLOUDINESS...HIGHS COULD BE A FEW DEGREES WARMER. THE BEST GUESS ON TONIGHTS LOWS IS FOR THE CLOUDS TO DEPART WITH WEAK SFC WINDS DEVELOPING AHEAD OF A COLD FRONT MOVING THROUGH SOUTH DAKOTA WHICH WOULD SUPPORT SOME RADIATIONAL COOLING ACROSS NEB. LOWS IN THE UPPER 20S TO MID 30S APPEARS TO BE THE BEST FORECAST. ADDITIONAL COOLING FROM THE DROUGHT CONDITIONS COULD PUSH LOWS FURTHER. THE REST OF THE FCST IS WELL BEHAVED. WINDS COULD REACH THE BREEZY CATEGORY BUT RELATIVE HUMIDITY WILL RUN 25 TO 30 PERCENT. THE RAP SUGGESTED LOWER RH ACROSS FAR NORTHWEST NEB AS THE FRONT NOSES SOUTH LATE THIS AFTN BUT AT THE SAME TIME WINDS WEAKEN. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 314 AM CDT WED APR 3 2013 12Z THURSDAY AND BEYOND. TWO MAIN CONCERNS GOING IN THE EXTENDED PERIOD. FIRST BEING THE POTENTIAL FOR FIRE HEADLINES ON FRIDAY...THEREAFTER THE FOCUS TURNS TO THE DEVELOPMENT OF A WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF WIDESPREAD PRECIPITATION BACK ACROSS THE FORECAST AREA LATE THIS WEEKEND THROUGH EARLY NEXT WEEK. SURFACE TEMPERATURES WILL SLOWLY MODERATE FROM WEST TO EAST ON THURSDAY AS SURFACE HIGH PRESSURE SLOWLY BUILDS EAST ACROSS THE NORTHERN PLAINS AND ALLOWS FOR A RETURN SOUTHERLY FLOW. A TIGHT GRADIENT IS EXPECTED IN THE TEMPERATURE FIELD...WITH HIGHS POSSIBLY APPROACHING 70 ACROSS SOUTHWEST NEBRASKA...BUT READINGS OF ONLY THE LOW TO MID 50S OVER NORTH CENTRAL NEBRASKA. FOR FRIDAY...THE NORTHERN PLAINS HIGH WILL BE LOCATED OVER THE GREAT LAKES REGION WITH STRONG SOUTHERLY RETURN FLOW TARGETING THE ENTIRE FORECAST AREA. WITH DEEPENING LOW PRESSURE ON THE LEE OF THE ROCKIES...A TIGHT PRESSURE GRADIENT IS EXPECTED...WITH THE POTENTIAL FOR WIND GUSTS IN EXCESS OF 25 MPH. MEANWHILE SFC TEMPERATURE AND DEW POINT SPREADS WILL APPROACH 40 F...WHICH SHOULD LEAD TO LOCALIZED AREAS OF SUB 20 PERCENT RH. GIVEN THAT GREEN UP HAS NOT YET OCCURRED...LOCALIZED RED FLAG CONDITIONS ARE POSSIBLE. UNCERTAINTY REMAINS IF THE RED FLAG CRITERIA WIND GUSTS WILL BE CO-LOCATED WITHIN THE CRITICAL RH FIELD. AT THIS TIME...IT APPEARS THAT THE STRONGEST GUSTS SHOULD OCCUR OVER EASTERN PORTIONS OF THE CWA...WHERE THE SOUTHERLY FLOW SHOULD HELP PUSH TD/S UP NEAR 40...WHICH WOULD KEEP MINIMUM RH IN THE 20-30 PERCENT RANGE. THE DRIEST AIR IS EXPECTED ACROSS THE WESTERN HALF OF THE CWA...SLIGHTLY REMOVED FROM THE STRONGEST GUSTS. OBVIOUSLY THERE IS STILL TIME TO HAMMER OUT THE DETAILS...BUT GIVEN A FAVORABLE FIRE WX PATTERN /RIDGE BREAKDOWN/ AND THE FACT THAT WIND SHIFT IS EXPECTED LATE AFTERNOON/EVENING AS A SURFACE TROUGH AND COLD FRONT ADVANCE EAST ACROSS THE CWA...ITS SAFE TO SAY AT THIS JUNCTURE THAT ELEVATED FIRE CONCERNS ARE CERTAINLY WARRANTED...WILL CONTINUE TO MONITOR. ALSO OF CONCERN...PROXIMITY SOUNDINGS INDICATE WEAK INSTABILITY ALONG THE FRONTAL PASSAGE...BUT DRY LOWER LEVELS...A FEW DRIER CG STRIKES COULD OCCUR. OTHERWISE HIGH TEMPERATURES WILL COOL SOME TEN DEGREES FROM THE MID 70S DOWN TO THE UPPER 50S TO MID 60S ON SATURDAY. LOWS FRIDAY AND SATURDAY MORNING WILL BE MILD RELATIVELY SPEAKING...WITH LOWS IN THE 30S FRIDAY...AND LOWS IN THE 40S SATURDAY MORNING. ATTENTION NOW TURNS TO THE MYRIAD OF POTENTIAL WEATHER FOR LATE SUNDAY THROUGH EARLY NEXT WEEK...BUT UNFORTUNATELY THE 03.00Z RUN OF THE MODELS FAILED TO INCREASE FORECAST CONFIDENCE AS SIGNIFICANT DIFFERENCES IN TIMING AND STRENGTH OF THE WESTERN CONUS TROUGH EXISTS. THE GENERAL IDEA IS THAT A SHORTWAVE WILL CROSS THE CENTRAL/NORTHERN PLAINS ON SUNDAY PROVIDING FOR SHOWERS AND/OR TSTMS...THEN THE MEAN TROUGH WILL DEVELOP OVER THE ROCKIES AND SLOWLY ADVANCE OUT ONTO THE PLAINS EARLY NEXT WEEK. THE EC SOLUTION CONTINUES TO ADVERTISE ENOUGH COLD AIR ON THE BACK SIDE OF THE MAIN H5 LOW TO ALLOW FOR SNOW ACCUMULATIONS...WHICH MAY BE SIGNIFICANT. ALSO OF NOTE...THE EC DEVELOPS H85 WINDS IN EXCESS OF 60KTS EARLY TUESDAY ACROSS EASTERN PORTIONS OF THE CWA. THE EURO HAS SHOWN A COLD BIAS WITH IT/S LAST STORM THAT AFFECTED OUR CWA...SO THE AMOUNT OF COOLING IS SUSPECT. THE GFS IS SHOWING A BIT MORE OF A SOUTHERLY TRACK OF THE MEAN TROUGH...AND IS LESS NEGATIVELY TILTED...BUT THE GFS ENSEMBLE MEAN GIVES SUPPORT TO THE EC SOLUTION. AS STATED PREVIOUSLY...CONFIDENCE IN ANY PARTICULAR SOLUTION IS LOW...THUS WILL MAINTAIN 40 PERCENT POPS OR LESS THROUGH THE EVENT AND KEEP THE GENERAL IDEA OF SHOWERS OF RAIN INITIALLY...THEN POSSIBLY CHANGING OVER TO SNOW MONDAY NIGHT INTO TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1240 AM CDT WED APR 3 2013 SATELLITE IMAGERY IS SHOWING LOW CLOUDS WITH CEILINGS 1000-2000 FEET AGL ACROSS EASTERN COLORADO AND 2000-3000 FEET IN NORTHWEST KANSAS AND EXTREME SOUTHWEST NEBRASKA. A PROJECTION OF THE CURRENT MOVEMENT KEEPS THE LOWER CLOUDS SOUTH OF AN OGA-LBF LINE. HOWEVER...LOW LEVEL WIND WOULD INDICATE SOME PROGRESS FARTHER NORTH THAN THAT. IN FACT...SHORT RANGE PROJECTIONS FROM THE EVENING MODEL RUN SHOW THE LOWER CLOUDS SPREADING THROUGH OGA TO MHN BUT STILL WEST OF LBF AND SOUTHWEST OF VTN. SO...FOR NOW...WE WILL KEEP LOW CEILINGS OUT OF THE FORECASTS FOR LBF AND VTN. WIND WILL BE BELOW 10KT UNTIL LATE MORNING...AROUND 15Z...WHEN IT WILL INCREASE AGAIN AND BECOME 190-220 AT 16-20G24-28KT IN THE NORTH AND 180-210 AT 12-14G18-24KT IN THE SOUTHWEST. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
410 AM CDT WED APR 3 2013 .SHORT TERM... MAJOR CHANGE TO THE FCST THIS MORNING IS TO CONSIDERABLY LOWER POPS ACROSS THE AREA. UNFORTUNATELY...PREVIOUS MODEL RUNS MISSED THE EXTENSIVE MCS THAT MOVED ACROSS AREAS FROM NW TEXAS TO SOUTH TEXAS. IT APPEARS THAT THIS MCS WILL LEAVE THE FCST AREA STARVED OF DEEP MOISTURE AND THUS THE LIFT ASSOCIATED WITH THE LOW OVER CNTL COLORADO WILL LIKELY PRODUCE MUCH LESS PRECIP THAN PREVIOUSLY EXPECTED. THE 00Z MODEL SUITE MISSED THIS CRITICAL ELEMENT RESULTING IN TOO MUCH WIDESPREAD QPF AND MOS GUIDANCE WHOSE POPS APPEAR TO BE TOO HIGH. HAVE TRENDED THE FCST MUCH CLOSER TO THE 06Z RUC WHICH DID INITIALIZE THE MCS AND SUBSEQUENTLY SEEMS TO HAVE A BETTER HANDLE ON POSSIBLE PRECIP TODAY. THAT POSSIBILITY THEN SEEMS TO FOCUS ON POTENTIAL FOR SCATTERED LIGHT SHOWERS MAINLY ACROSS THE NRN ZONES IN AN AREA OF LIFT JUST AHEAD AND SOUTH OF THE TRACK OF THE UPPER LOW. PRECIP HAS BEEN HARD TO COME BY VCNTY OF THE LOW WITH SOME LIGHT RA AND SN IN SRN COLORADO AND SOME LIGHT RA SOUTH OF KABQ IN CNTL NM AS A JET STREAK ROTATES AROUND THE BASE OF THE TROUGH. IN THE NEAR TERM EVEN DRIZZLE CHANCES APPEAR TO BE ON THE WANE AS A MID LEVEL DRY SLOT AND SOME APPARENT DOWNWARD MOTION TO THE REAR OF THE CNTL TX MCS WORK IN ACROSS THE AREA. COULD SEE DRIZZLE TRY TO REDEVELOP A LITTLE LATER THIS MORNING ONCE SOME WEAK LIFT WORKS BACK OVER THE AREA...BUT EVEN MEASURABLE PRECIP FROM THIS ELEMENT LOOKING VERY UNLIKELY. TEMP FCST WILL BE TRICKY FOR THIS AFTN WITH SOME UNCERTAINTY REGARDING HOW MUCH LOW STRATUS WILL REMAIN IN PLACE OR THIN. 00Z MODELS APPEAR TO BE TOO AGGRESSIVE WITH WARMING AND HAVE TRENDED TEMPS A BIT BELOW MOS. HOWEVER...ANY LATE DAY CLEARING OR LIFTING OF CEILINGS AS THE CENTER OF THE LOW MOVES ACROSS THE SRN PANHANDLE WOULD SEE TEMPS APPROACH THAT PROGGED BY MOS. THIS WOULD BE MOST LIKELY TO OCCUR ACROSS THE SWRN ZONES. MOVING INTO TONIGHT...LESSENING RAIN CHANCES SHOULD SHIFT EAST OF THE AREA BY EARLY EVENING. MODELS KEEP LOW LEVEL MOISTURE LEVELS PRETTY STEADY WHILE DROPPING WINDS OFF TO BECOME VERY LIGHT. SOME HINTING OF FOG POTENTIAL LATE TONIGHT...AND IF MORE RAIN HAD FALLEN IN THE LAST 24 HOURS OR MORE FALLS THAN EXPECTED OVER THE NEXT SEVERAL HOURS WOULD BE MORE INCLINED TO MENTION AREAS OF FOG IN THE FCST. STILL A BIT TOO MUCH UNCERTAINTY HERE AND WILL LET NEXT SHIFT REEVALUATE THAT POTENTIAL. && .LONG TERM... A RETURN TO MORE SEASONABLE TEMPS REMAINS ON TRACK BEGINNING TOMORROW AS THE SOUTH PLAINS SHAKES THE RECENT FORAY OF MODIFIED CANADIAN AIR. A BEVERAGE SUCH AS CANADA DRY WOULD PROVE FITTING FOR THE NEXT SEVERAL DAYS AS TRANSIENT RIDGING ALOFT CARRIES A DOME OF VERY MILD AND DRY AIR EAST OVER MUCH OF THE SOUTH PLAINS. BY FRIDAY...WE SHOULD SEE A PALTRY DRYLINE EVOLVE IN THE ROLLING PLAINS BEHIND THE DEPARTING SURFACE HIGH. QUALITY RETURN FLOW HOWEVER IS NOT EXPECTED UNTIL SATURDAY AT WHICH POINT STRONGER WESTERLY WINDS ALOFT BEHIND THE UPPER RIDGE WILL SHUNT MUCH OF THIS SHALLOW MOISTURE OUT OF ALL BUT OUR FAR EASTERN COLUMN OF COUNTIES. A MINOR SHORT WAVE TROUGH IS STILL PROGGED TO SLIDE THROUGH THIS STRONGER WESTERLY FLOW BY SAT NIGHT/SUN MORNING ACCOMPANIED BY PERHAPS EVEN DRIER AND WARMER CONDITIONS ON SUNDAY...BUT WILL STICK WITH SLIGHTLY COOLER CONDITIONS AS A COLD FRONT WILL BE FOUND EDGING PERILOUSLY CLOSE TO OUR NRN COUNTIES IN THE WAKE OF THIS UPPER IMPULSE. BY EARLY NEXT WEEK...NO CHANGES ARE WARRANTED ATTM AS MODELS ARE NOW IN MORE DISAGREEMENT THAN 24 HOURS AGO. WPC CONTINUES TO FAVOR A SLOWER AND DEEPER LONGWAVE TROUGH EVOLVING IN THE GREAT BASIN AND FOUR CORNERS REGION BY THIS TIME. ONLY SIMILARITY AMONG THE CURRENT ECMWF AND GFS IS THAT THIS WAVE WOULD BE OPEN AND PROGRESSIVE...THOUGH SIGNIFICANT DIFFERENCES EMERGE IN THE TIMING OF SAID WAVE AND HOW MUCH CP AIR IS DRAWN SOUTHWARD FOLLOWING ITS PASSAGE. WOULD STILL EXPECT A SEMI-ACTIVE DRYLINE TO UNFOLD NEAR THE FRINGES OF OUR EASTERN COUNTIES AS EARLY AS MON AND PERHAPS LINGERING INTO TUE UNDERNEATH AN INCREASINGLY UNSETTLED SWLY UPPER FLOW REGIME. THE GEFS MEAN AND EVEN THE CMC INDICATE SUCH A SCENARIO THAT AS OF YESTERDAY WAS FAVORED BY THE ECMWF...BUT WILL AWAIT LATER MODEL RUNS BEFORE COMMITTING TO ANY CHANGES STILL SO MANY PERIODS OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 46 32 68 43 76 / 40 10 0 0 0 TULIA 41 32 67 43 77 / 40 10 0 0 0 PLAINVIEW 41 34 68 44 77 / 30 10 0 0 0 LEVELLAND 48 34 70 46 81 / 30 10 0 0 0 LUBBOCK 43 35 70 45 79 / 30 10 0 0 0 DENVER CITY 51 34 70 47 82 / 20 10 0 0 0 BROWNFIELD 48 35 70 46 82 / 30 10 0 0 0 CHILDRESS 43 35 64 43 78 / 40 20 0 0 0 SPUR 41 35 68 45 81 / 30 10 0 0 0 ASPERMONT 43 37 66 44 80 / 30 10 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07/93
AREA FORECAST DISCUSSION
NWS PUEBLO CO
700 AM MDT WED APR 3 2013 .UPDATE... ISSUED AT 655 AM MDT WED APR 3 2013 UPDATED FORECAST TO REFLECT CURRENT CONDITIONS. REMOVED DRIZZLE/FOG FROM SOUTHERN I-25 CORRIDOR AS VISIBILITY HAS BEEN IMPROVING MOST AREAS. STILL SOME DENSE FOG AND PATCHY FREEZING DRIZZLE ACROSS EL PASO COUNTY THROUGH MID-MRNG AS WINDS HAVE YET TO GO NORTHERLY. ALSO ADDED A COUPLE HOURS OF LIGHT SNOW TO SAN LUIS VALLEY...WHERE ALAMOSA HAS BEEN REPORTING SNOW THE PAST HOUR. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 352 AM MDT WED APR 3 2013 UPPER LOW GRADUALLY SLIPPING EASTWARD ACROSS THE STATE EARLY THIS MORNING...AND SHOULD MOVE INTO THE SOUTHERN PLAINS BY THIS EVENING. STILL SOME RESIDUAL -SHRA/-SHSN/-FZDZ ACROSS THE AREA THIS MORNING...THOUGH RADAR TRENDS SUGGEST GRADUALLY DECREASING COVERAGE AND INTENSITY SINCE 09Z. WILL HOLD ON TO SOME LIGHT PRECIP THROUGH THE MORNING MOST AREAS...GRADUALLY ENDING FROM NW TO SE BY MIDDAY. MAY SEE A FEW SHOWERS REFIRE OVER THE MTS THIS AFTERNOON AS LAPSE RATES REMAIN FAIRLY STEEP...THOUGH PRECIP WILL BE VERY LIGHT. PERSISTENT -FZDZ AND FZFG OVER EL PASO COUNTY MAY LINGER THROUGH LATE MORNING...AS LATEST HRRR KEEPS WEAK SOUTHEAST WIND IN PLACE UNTIL 17Z. STILL THINK N-NW FLOW WILL DEVELOP THIS AFTERNOON AND GRADUALLY REMOVE ANY REMNANTS OF CLOUDS/FOG...THOUGH FAR SOUTHEAST PLAINS MAY HAVE TO WAIT UNTIL VERY LATE AFTERNOON TO SEE ANY SUN. WILL CONTINUE WITH REASONABLY MILD MAX TEMPS MOST LOCATIONS...THOUGH KEPT AREAS AROUND SPRINGFIELD COLDER THAN GUIDANCE DUE TO LINGERING CLOUDS. OVERNIGHT...WILL END PRECIP QUICKLY IN THE EVENING WITH LOSS OF HEATING...LEADING TO A MOSTLY CLEAR AND SEASONABLY COOL NIGHT MOST AREAS UNDER WEAK NORTHWEST FLOW. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 352 AM MDT WED APR 3 2013 ...SIGNIFICANT STORM POSSIBLE EARLY NEXT WEEK... LATTER HALF OF THIS WEEK LOOKS QUITE PLEASANT AS A TRANSITORY RIDGE CROSSES OUR AREA. THURSDAY MAY BE THE NICEST DAY...WITH DRY AND CLEAR CONDITIONS EXPECTED AREA-WIDE. WINDS SHOULD BE RELATIVELY LIGHT WITH THE RIDGE AXIS JUST WWD OF THE CWA. GIVEN THE LIGHT WINDS AND H7 TEMPS AROUND 4 DEGREES OR SO...HAVE GONE ON THE LOW SIDE OF MOS FOR TEMPS ON THE PLAINS...WITH HIGHS EXPECTED TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. FRIDAY...FIRE WX ISSUES ARISE AS THE RIDGE SHIFTS TO THE EAST...AND ZONAL FLOW STRENGTHENS ACROSS THE CONTDVD. SHOULD SEE MARGINALLY CRITICAL FIRE WX CONDITIONS DEVELOP ACROSS THE PLAINS AS RH DROPS TO BELOW 15 PERCENT AND W WINDS BECOME RATHER GUSTY BY AFTERNOON. FOR THE WEEKEND...A WEAK SHORTWAVE TROUGH WILL MOVE THROUGH THE NRN ROCKIES...AND WILL LIKELY SPARK SCT-NMRS SHOWERS ACROSS THE MTS ESPECIALLY SAT AFTERNOON-EVE. MAIN CHANCES FOR PRECIP WILL BE N OF HIGHWAY 50 BOTH DAYS. TEMPS SHOULD REMAIN QUITE PLEASANT...IN THE MID 60S ACROSS THE PLAINS AND 50S FOR THE MTS AND HIGH VALLEYS. MAIN FOCUS IN THE EXTENDED CONTINUES TO BE THE LARGE SPRING STORM SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA BY LATE IN THE WEEKEND THROUGH THE FIRST HALF OF NEXT WEEK. ENSEMBLE MEANS CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SRN ROCKIES FROM MON THROUGH WEDNESDAY. OP RUNS OF THE GFS AND ECMWF ALSO CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SOUTHERN ROCKIES DURING THIS TIME FRAME. HOWEVER...SIGNIFICANT DIFFERENCES REMAIN IN THE EVOLUTION OF THE TROUGH PER THE GFS AND EC. THE 00Z EC IS MORE PROGRESSIVE...BUT SPLITS THE TROUGH...WITH THE MAIN ENERGY ARRIVING SUNDAY NIGHT THRU MONDAY...AND A SECONDARY LOW MOVING THROUGH NEXT WED. THE GFS BRINGS THE LOW THROUGH IN ONE PIECE...BUT IS SLOWER AND TARGETS THE MON NIGHT-TUESDAY TIME FRAME FOR THE HIGHEST POPS. BOTH MODELS PROG SIGNIFICANT QPF FOR SE CO...BETWEEN 1-2 INCHES OF LIQUID FOR THE SUN-WED TIME PERIOD. BOTH MODELS ALSO TARGET THE SERN MTS FOR THE HIGHEST PRECIP POTENTIAL. WHILE SNOW LEVELS LOOK TO REMAIN FAIRLY HIGH FOR THE BULK OF THIS EVENT...THE SE MTS ABOVE 7000 FEET WOULD PICK UP SIGNIFICANT SNOWFALL IN EITHER SCENARIO. THE ECMWF BRINGS IN UNUSUALLY COLD AIR BEHIND THE TROUGH BY WED...WITH H7 TEMPS BOTTOMING OUT NEAR MINUS 16 DEGREES. IF THIS OCCURS...THE HIGH TEMPS FOR NEXT WED MAY NEED TO BE SUBSTANTIALLY REDUCED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 352 AM MDT WED APR 3 2013 AT KCOS...PERSISTENT SE SURFACE WIND HAS PRODUCED DENSE FZFG AND FZDZ EARLY THIS MORNING...AND EXPECT LIFR CONDITIONS TO PERSIST UNTIL 14Z...THEN IFR FROM 14-17Z AS FOG/CIGS BEGIN TO LIFT. PRECIP AMOUNTS AND ANY ICING THIS MORNING SHOULD BE MINIMAL. WILL SEE VFR CONDITIONS RETURN 17Z-18Z AS LIGHT NORTH WIND DEVELOP...THEN VFR CONDITIONS FOR THE REMAINDER OF TODAY AND TONIGHT WITH LIGHT WINDS. MAY SEE A -SHRA OVER THE MOUNTAINS WEST OF THE AIRPORT AFTER 18Z...THOUGH CHANCE OF ANY SHOWERS AT THE TERMINAL LOOKS TOO LOW TO MENTION IN THE TAF. AT KPUB...E-SE WIND WILL KEEP IFR STRATUS IN PLACE UNTIL 14-15Z...THEN GRADUAL CLEARING BY 17Z AS WINDS BECOME LIGHT N. EXPECT VFR CONDITIONS FROM 17Z ONWARD THROUGH THE AFTERNOON AND OVERNIGHT WITH LIGHT WINDS. AT KALS...SOME PATCHY MVFR STRATUS EARLY THIS MORNING WILL DISSIPATE BY 14Z...THEN VFR CONDITIONS FOR THE REMAINDER OF TODAY AND TONIGHT WITH LIGHT WINDS. MAY SEE A -SHRA OVER THE MOUNTAINS SURROUNDING THE AREA AFTER 18Z...THOUGH IT APPEARS DOUBTFUL ANY WILL MOVE TOWARD THE TERMINAL. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PETERSEN SHORT TERM...PETERSEN LONG TERM...ROSE AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
428 AM MDT WED APR 3 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 352 AM MDT WED APR 3 2013 UPPER LOW GRADUALLY SLIPPING EASTWARD ACROSS THE STATE EARLY THIS MORNING...AND SHOULD MOVE INTO THE SOUTHERN PLAINS BY THIS EVENING. STILL SOME RESIDUAL -SHRA/-SHSN/-FZDZ ACROSS THE AREA THIS MORNING...THOUGH RADAR TRENDS SUGGEST GRADUALLY DECREASING COVERAGE AND INTENSITY SINCE 09Z. WILL HOLD ON TO SOME LIGHT PRECIP THROUGH THE MORNING MOST AREAS...GRADUALLY ENDING FROM NW TO SE BY MIDDAY. MAY SEE A FEW SHOWERS REFIRE OVER THE MTS THIS AFTERNOON AS LAPSE RATES REMAIN FAIRLY STEEP...THOUGH PRECIP WILL BE VERY LIGHT. PERSISTENT -FZDZ AND FZFG OVER EL PASO COUNTY MAY LINGER THROUGH LATE MORNING...AS LATEST HRRR KEEPS WEAK SOUTHEAST WIND IN PLACE UNTIL 17Z. STILL THINK N-NW FLOW WILL DEVELOP THIS AFTERNOON AND GRADUALLY REMOVE ANY REMNANTS OF CLOUDS/FOG...THOUGH FAR SOUTHEAST PLAINS MAY HAVE TO WAIT UNTIL VERY LATE AFTERNOON TO SEE ANY SUN. WILL CONTINUE WITH REASONABLY MILD MAX TEMPS MOST LOCATIONS...THOUGH KEPT AREAS AROUND SPRINGFIELD COLDER THAN GUIDANCE DUE TO LINGERING CLOUDS. OVERNIGHT...WILL END PRECIP QUICKLY IN THE EVENING WITH LOSS OF HEATING...LEADING TO A MOSTLY CLEAR AND SEASONABLY COOL NIGHT MOST AREAS UNDER WEAK NORTHWEST FLOW. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 352 AM MDT WED APR 3 2013 ...SIGNIFICANT STORM POSSIBLE EARLY NEXT WEEK... LATTER HALF OF THIS WEEK LOOKS QUITE PLEASANT AS A TRANSITORY RIDGE CROSSES OUR AREA. THURSDAY MAY BE THE NICEST DAY...WITH DRY AND CLEAR CONDITIONS EXPECTED AREA-WIDE. WINDS SHOULD BE RELATIVELY LIGHT WITH THE RIDGE AXIS JUST WWD OF THE CWA. GIVEN THE LIGHT WINDS AND H7 TEMPS AROUND 4 DEGREES OR SO...HAVE GONE ON THE LOW SIDE OF MOS FOR TEMPS ON THE PLAINS...WITH HIGHS EXPECTED TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. FRIDAY...FIRE WX ISSUES ARISE AS THE RIDGE SHIFTS TO THE EAST...AND ZONAL FLOW STRENGTHENS ACROSS THE CONTDVD. SHOULD SEE MARGINALLY CRITICAL FIRE WX CONDITIONS DEVELOP ACROSS THE PLAINS AS RH DROPS TO BELOW 15 PERCENT AND W WINDS BECOME RATHER GUSTY BY AFTERNOON. FOR THE WEEKEND...A WEAK SHORTWAVE TROUGH WILL MOVE THROUGH THE NRN ROCKIES...AND WILL LIKELY SPARK SCT-NMRS SHOWERS ACROSS THE MTS ESPECIALLY SAT AFTERNOON-EVE. MAIN CHANCES FOR PRECIP WILL BE N OF HIGHWAY 50 BOTH DAYS. TEMPS SHOULD REMAIN QUITE PLEASANT...IN THE MID 60S ACROSS THE PLAINS AND 50S FOR THE MTS AND HIGH VALLEYS. MAIN FOCUS IN THE EXTENDED CONTINUES TO BE THE LARGE SPRING STORM SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA BY LATE IN THE WEEKEND THROUGH THE FIRST HALF OF NEXT WEEK. ENSEMBLE MEANS CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SRN ROCKIES FROM MON THROUGH WEDNESDAY. OP RUNS OF THE GFS AND ECMWF ALSO CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SOUTHERN ROCKIES DURING THIS TIME FRAME. HOWEVER...SIGNIFICANT DIFFERENCES REMAIN IN THE EVOLUTION OF THE TROUGH PER THE GFS AND EC. THE 00Z EC IS MORE PROGRESSIVE...BUT SPLITS THE TROUGH...WITH THE MAIN ENERGY ARRIVING SUNDAY NIGHT THRU MONDAY...AND A SECONDARY LOW MOVING THROUGH NEXT WED. THE GFS BRINGS THE LOW THROUGH IN ONE PIECE...BUT IS SLOWER AND TARGETS THE MON NIGHT-TUESDAY TIME FRAME FOR THE HIGHEST POPS. BOTH MODELS PROG SIGNIFICANT QPF FOR SE CO...BETWEEN 1-2 INCHES OF LIQUID FOR THE SUN-WED TIME PERIOD. BOTH MODELS ALSO TARGET THE SERN MTS FOR THE HIGHEST PRECIP POTENTIAL. WHILE SNOW LEVELS LOOK TO REMAIN FAIRLY HIGH FOR THE BULK OF THIS EVENT...THE SE MTS ABOVE 7000 FEET WOULD PICK UP SIGNIFICANT SNOWFALL IN EITHER SCENARIO. THE ECMWF BRINGS IN UNUSUALLY COLD AIR BEHIND THE TROUGH BY WED...WITH H7 TEMPS BOTTOMING OUT NEAR MINUS 16 DEGREES. IF THIS OCCURS...THE HIGH TEMPS FOR NEXT WED MAY NEED TO BE SUBSTANTIALLY REDUCED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 352 AM MDT WED APR 3 2013 AT KCOS...PERSISTENT SE SURFACE WIND HAS PRODUCED DENSE FZFG AND FZDZ EARLY THIS MORNING...AND EXPECT LIFR CONDITIONS TO PERSIST UNTIL 14Z...THEN IFR FROM 14-17Z AS FOG/CIGS BEGIN TO LIFT. PRECIP AMOUNTS AND ANY ICING THIS MORNING SHOULD BE MINIMAL. WILL SEE VFR CONDITIONS RETURN 17Z-18Z AS LIGHT NORTH WIND DEVELOP...THEN VFR CONDITIONS FOR THE REMAINDER OF TODAY AND TONIGHT WITH LIGHT WINDS. MAY SEE A -SHRA OVER THE MOUNTAINS WEST OF THE AIRPORT AFTER 18Z...THOUGH CHANCE OF ANY SHOWERS AT THE TERMINAL LOOKS TOO LOW TO MENTION IN THE TAF. AT KPUB...E-SE WIND WILL KEEP IFR STRATUS IN PLACE UNTIL 14-15Z...THEN GRADUAL CLEARING BY 17Z AS WINDS BECOME LIGHT N. EXPECT VFR CONDITIONS FROM 17Z ONWARD THROUGH THE AFTERNOON AND OVERNIGHT WITH LIGHT WINDS. AT KALS...SOME PATCHY MVFR STRATUS EARLY THIS MORNING WILL DISSIPATE BY 14Z...THEN VFR CONDITIONS FOR THE REMAINDER OF TODAY AND TONIGHT WITH LIGHT WINDS. MAY SEE A -SHRA OVER THE MOUNTAINS SURROUNDING THE AREA AFTER 18Z...THOUGH IT APPEARS DOUBTFUL ANY WILL MOVE TOWARD THE TERMINAL. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PETERSEN LONG TERM...ROSE AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
622 AM CDT WED APR 3 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CDT WED APR 3 2013 THE RAP...NAM AND GFS ARE SUGGESTING SUFFICIENT LOW AND MID LEVEL CLOUDINESS ACROSS SRN NEB TO HOLD TEMPS IN THE 50S TODAY. AT THE SAME TIME SOUTH AND SOUTHWEST WINDS WILL RECIRCULATE COOL AIR NORTH FROM THE HIGH PRESSURE SYSTEM ACROSS THE MID SOUTH. SO THE RAP 21Z TEMPS WERE USED AS THE BASIS FOR TODAYS HIGHS WHICH IS CLOSE TO THE GUIDANCE DATA SETS. IF FULL SUN ARRIVES OR EVEN JUST HIGH LEVEL CLOUDINESS...HIGHS COULD BE A FEW DEGREES WARMER. THE BEST GUESS ON TONIGHTS LOWS IS FOR THE CLOUDS TO DEPART WITH WEAK SFC WINDS DEVELOPING AHEAD OF A COLD FRONT MOVING THROUGH SOUTH DAKOTA WHICH WOULD SUPPORT SOME RADIATIONAL COOLING ACROSS NEB. LOWS IN THE UPPER 20S TO MID 30S APPEARS TO BE THE BEST FORECAST. ADDITIONAL COOLING FROM THE DROUGHT CONDITIONS COULD PUSH LOWS FURTHER. THE REST OF THE FCST IS WELL BEHAVED. WINDS COULD REACH THE BREEZY CATEGORY BUT RELATIVE HUMIDITY WILL RUN 25 TO 30 PERCENT. THE RAP SUGGESTED LOWER RH ACROSS FAR NORTHWEST NEB AS THE FRONT NOSES SOUTH LATE THIS AFTN BUT AT THE SAME TIME WINDS WEAKEN. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 314 AM CDT WED APR 3 2013 12Z THURSDAY AND BEYOND. TWO MAIN CONCERNS GOING IN THE EXTENDED PERIOD. FIRST BEING THE POTENTIAL FOR FIRE HEADLINES ON FRIDAY...THEREAFTER THE FOCUS TURNS TO THE DEVELOPMENT OF A WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF WIDESPREAD PRECIPITATION BACK ACROSS THE FORECAST AREA LATE THIS WEEKEND THROUGH EARLY NEXT WEEK. SURFACE TEMPERATURES WILL SLOWLY MODERATE FROM WEST TO EAST ON THURSDAY AS SURFACE HIGH PRESSURE SLOWLY BUILDS EAST ACROSS THE NORTHERN PLAINS AND ALLOWS FOR A RETURN SOUTHERLY FLOW. A TIGHT GRADIENT IS EXPECTED IN THE TEMPERATURE FIELD...WITH HIGHS POSSIBLY APPROACHING 70 ACROSS SOUTHWEST NEBRASKA...BUT READINGS OF ONLY THE LOW TO MID 50S OVER NORTH CENTRAL NEBRASKA. FOR FRIDAY...THE NORTHERN PLAINS HIGH WILL BE LOCATED OVER THE GREAT LAKES REGION WITH STRONG SOUTHERLY RETURN FLOW TARGETING THE ENTIRE FORECAST AREA. WITH DEEPENING LOW PRESSURE ON THE LEE OF THE ROCKIES...A TIGHT PRESSURE GRADIENT IS EXPECTED...WITH THE POTENTIAL FOR WIND GUSTS IN EXCESS OF 25 MPH. MEANWHILE SFC TEMPERATURE AND DEW POINT SPREADS WILL APPROACH 40 F...WHICH SHOULD LEAD TO LOCALIZED AREAS OF SUB 20 PERCENT RH. GIVEN THAT GREEN UP HAS NOT YET OCCURRED...LOCALIZED RED FLAG CONDITIONS ARE POSSIBLE. UNCERTAINTY REMAINS IF THE RED FLAG CRITERIA WIND GUSTS WILL BE CO-LOCATED WITHIN THE CRITICAL RH FIELD. AT THIS TIME...IT APPEARS THAT THE STRONGEST GUSTS SHOULD OCCUR OVER EASTERN PORTIONS OF THE CWA...WHERE THE SOUTHERLY FLOW SHOULD HELP PUSH TD/S UP NEAR 40...WHICH WOULD KEEP MINIMUM RH IN THE 20-30 PERCENT RANGE. THE DRIEST AIR IS EXPECTED ACROSS THE WESTERN HALF OF THE CWA...SLIGHTLY REMOVED FROM THE STRONGEST GUSTS. OBVIOUSLY THERE IS STILL TIME TO HAMMER OUT THE DETAILS...BUT GIVEN A FAVORABLE FIRE WX PATTERN /RIDGE BREAKDOWN/ AND THE FACT THAT WIND SHIFT IS EXPECTED LATE AFTERNOON/EVENING AS A SURFACE TROUGH AND COLD FRONT ADVANCE EAST ACROSS THE CWA...ITS SAFE TO SAY AT THIS JUNCTURE THAT ELEVATED FIRE CONCERNS ARE CERTAINLY WARRANTED...WILL CONTINUE TO MONITOR. ALSO OF CONCERN...PROXIMITY SOUNDINGS INDICATE WEAK INSTABILITY ALONG THE FRONTAL PASSAGE...BUT DRY LOWER LEVELS...A FEW DRIER CG STRIKES COULD OCCUR. OTHERWISE HIGH TEMPERATURES WILL COOL SOME TEN DEGREES FROM THE MID 70S DOWN TO THE UPPER 50S TO MID 60S ON SATURDAY. LOWS FRIDAY AND SATURDAY MORNING WILL BE MILD RELATIVELY SPEAKING...WITH LOWS IN THE 30S FRIDAY...AND LOWS IN THE 40S SATURDAY MORNING. ATTENTION NOW TURNS TO THE MYRIAD OF POTENTIAL WEATHER FOR LATE SUNDAY THROUGH EARLY NEXT WEEK...BUT UNFORTUNATELY THE 03.00Z RUN OF THE MODELS FAILED TO INCREASE FORECAST CONFIDENCE AS SIGNIFICANT DIFFERENCES IN TIMING AND STRENGTH OF THE WESTERN CONUS TROUGH EXISTS. THE GENERAL IDEA IS THAT A SHORTWAVE WILL CROSS THE CENTRAL/NORTHERN PLAINS ON SUNDAY PROVIDING FOR SHOWERS AND/OR TSTMS...THEN THE MEAN TROUGH WILL DEVELOP OVER THE ROCKIES AND SLOWLY ADVANCE OUT ONTO THE PLAINS EARLY NEXT WEEK. THE EC SOLUTION CONTINUES TO ADVERTISE ENOUGH COLD AIR ON THE BACK SIDE OF THE MAIN H5 LOW TO ALLOW FOR SNOW ACCUMULATIONS...WHICH MAY BE SIGNIFICANT. ALSO OF NOTE...THE EC DEVELOPS H85 WINDS IN EXCESS OF 60KTS EARLY TUESDAY ACROSS EASTERN PORTIONS OF THE CWA. THE EURO HAS SHOWN A COLD BIAS WITH IT/S LAST STORM THAT AFFECTED OUR CWA...SO THE AMOUNT OF COOLING IS SUSPECT. THE GFS IS SHOWING A BIT MORE OF A SOUTHERLY TRACK OF THE MEAN TROUGH...AND IS LESS NEGATIVELY TILTED...BUT THE GFS ENSEMBLE MEAN GIVES SUPPORT TO THE EC SOLUTION. AS STATED PREVIOUSLY...CONFIDENCE IN ANY PARTICULAR SOLUTION IS LOW...THUS WILL MAINTAIN 40 PERCENT POPS OR LESS THROUGH THE EVENT AND KEEP THE GENERAL IDEA OF SHOWERS OF RAIN INITIALLY...THEN POSSIBLY CHANGING && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 630 AM CDT WED APR 3 2013 VFR IS GENERALLY EXPECTED ACROSS ALL AREAS TODAY AND TONIGHT. LOCAL MVFR/IFR CIGS ARE MOVING NORTH THROUGH THE NEB PANHANDLE SOUTH OF KAIA. THIS SHOULD MOVE NORTH TO NEAR KAIA THIS MORNING AND THEN MIX OUT. A NARROW BAND OF MVFR CIGS COULD DEVELOP AOA 06Z TONIGHT ALONG HIGHWAY 20 AS A COLD FRONT DROPS INTO NRN NEB. OTHERWISE VFR SHOULD PREVAIL. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...CDC
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
634 AM CDT WED APR 3 2013 .AVIATION... IFR CONDITIONS LIKELY TO PERSIST INTO THE AFTN HOURS AT BOTH TAF SITES. KLBB MAY SEE SOME LIFTING OF THE CIGS THIS AFTN THEN PROBABLY SCATTER OUT THIS EVENING. KCDS LOOKS LESS LIKELY TO SEE MUCH IMPROVEMENT UNTIL LATE IN THE TAF PERIOD OR BEYOND. DEEP MOISTURE NOT AS RICH AS EXPECTED WHICH WILL RESULT IN GREATLY REDUCED PRECIP CHANCES TODAY. BOTH TAF SITES...KCDS MORESO THAN KLBB...COULD SEE SOME LIGHT SHOWERS BUT CHANCES NOW LOOK TO SLIM TO MENTION GIVEN RESTRICTIONS ON PROB30 GROUP WITHIN FIRST 9 HOURS OF TAF PERIOD. && .PREV DISCUSSION... /ISSUED 410 AM CDT WED APR 3 2013/ SHORT TERM... MAJOR CHANGE TO THE FCST THIS MORNING IS TO CONSIDERABLY LOWER POPS ACROSS THE AREA. UNFORTUNATELY...PREVIOUS MODEL RUNS MISSED THE EXTENSIVE MCS THAT MOVED ACROSS AREAS FROM NW TEXAS TO SOUTH TEXAS. IT APPEARS THAT THIS MCS WILL LEAVE THE FCST AREA STARVED OF DEEP MOISTURE AND THUS THE LIFT ASSOCIATED WITH THE LOW OVER CNTL COLORADO WILL LIKELY PRODUCE MUCH LESS PRECIP THAN PREVIOUSLY EXPECTED. THE 00Z MODEL SUITE MISSED THIS CRITICAL ELEMENT RESULTING IN TOO MUCH WIDESPREAD QPF AND MOS GUIDANCE WHOSE POPS APPEAR TO BE TOO HIGH. HAVE TRENDED THE FCST MUCH CLOSER TO THE 06Z RUC WHICH DID INITIALIZE THE MCS AND SUBSEQUENTLY SEEMS TO HAVE A BETTER HANDLE ON POSSIBLE PRECIP TODAY. THAT POSSIBILITY THEN SEEMS TO FOCUS ON POTENTIAL FOR SCATTERED LIGHT SHOWERS MAINLY ACROSS THE NRN ZONES IN AN AREA OF LIFT JUST AHEAD AND SOUTH OF THE TRACK OF THE UPPER LOW. PRECIP HAS BEEN HARD TO COME BY VCNTY OF THE LOW WITH SOME LIGHT RA AND SN IN SRN COLORADO AND SOME LIGHT RA SOUTH OF KABQ IN CNTL NM AS A JET STREAK ROTATES AROUND THE BASE OF THE TROUGH. IN THE NEAR TERM EVEN DRIZZLE CHANCES APPEAR TO BE ON THE WANE AS A MID LEVEL DRY SLOT AND SOME APPARENT DOWNWARD MOTION TO THE REAR OF THE CNTL TX MCS WORK IN ACROSS THE AREA. COULD SEE DRIZZLE TRY TO REDEVELOP A LITTLE LATER THIS MORNING ONCE SOME WEAK LIFT WORKS BACK OVER THE AREA...BUT EVEN MEASURABLE PRECIP FROM THIS ELEMENT LOOKING VERY UNLIKELY. TEMP FCST WILL BE TRICKY FOR THIS AFTN WITH SOME UNCERTAINTY REGARDING HOW MUCH LOW STRATUS WILL REMAIN IN PLACE OR THIN. 00Z MODELS APPEAR TO BE TOO AGGRESSIVE WITH WARMING AND HAVE TRENDED TEMPS A BIT BELOW MOS. HOWEVER...ANY LATE DAY CLEARING OR LIFTING OF CEILINGS AS THE CENTER OF THE LOW MOVES ACROSS THE SRN PANHANDLE WOULD SEE TEMPS APPROACH THAT PROGGED BY MOS. THIS WOULD BE MOST LIKELY TO OCCUR ACROSS THE SWRN ZONES. MOVING INTO TONIGHT...LESSENING RAIN CHANCES SHOULD SHIFT EAST OF THE AREA BY EARLY EVENING. MODELS KEEP LOW LEVEL MOISTURE LEVELS PRETTY STEADY WHILE DROPPING WINDS OFF TO BECOME VERY LIGHT. SOME HINTING OF FOG POTENTIAL LATE TONIGHT...AND IF MORE RAIN HAD FALLEN IN THE LAST 24 HOURS OR MORE FALLS THAN EXPECTED OVER THE NEXT SEVERAL HOURS WOULD BE MORE INCLINED TO MENTION AREAS OF FOG IN THE FCST. STILL A BIT TOO MUCH UNCERTAINTY HERE AND WILL LET NEXT SHIFT REEVALUATE THAT POTENTIAL. LONG TERM... A RETURN TO MORE SEASONABLE TEMPS REMAINS ON TRACK BEGINNING TOMORROW AS THE SOUTH PLAINS SHAKES THE RECENT FORAY OF MODIFIED CANADIAN AIR. A BEVERAGE SUCH AS CANADA DRY WOULD PROVE FITTING FOR THE NEXT SEVERAL DAYS AS TRANSIENT RIDGING ALOFT CARRIES A DOME OF VERY MILD AND DRY AIR EAST OVER MUCH OF THE SOUTH PLAINS. BY FRIDAY...WE SHOULD SEE A PALTRY DRYLINE EVOLVE IN THE ROLLING PLAINS BEHIND THE DEPARTING SURFACE HIGH. QUALITY RETURN FLOW HOWEVER IS NOT EXPECTED UNTIL SATURDAY AT WHICH POINT STRONGER WESTERLY WINDS ALOFT BEHIND THE UPPER RIDGE WILL SHUNT MUCH OF THIS SHALLOW MOISTURE OUT OF ALL BUT OUR FAR EASTERN COLUMN OF COUNTIES. A MINOR SHORT WAVE TROUGH IS STILL PROGGED TO SLIDE THROUGH THIS STRONGER WESTERLY FLOW BY SAT NIGHT/SUN MORNING ACCOMPANIED BY PERHAPS EVEN DRIER AND WARMER CONDITIONS ON SUNDAY...BUT WILL STICK WITH SLIGHTLY COOLER CONDITIONS AS A COLD FRONT WILL BE FOUND EDGING PERILOUSLY CLOSE TO OUR NRN COUNTIES IN THE WAKE OF THIS UPPER IMPULSE. BY EARLY NEXT WEEK...NO CHANGES ARE WARRANTED ATTM AS MODELS ARE NOW IN MORE DISAGREEMENT THAN 24 HOURS AGO. WPC CONTINUES TO FAVOR A SLOWER AND DEEPER LONGWAVE TROUGH EVOLVING IN THE GREAT BASIN AND FOUR CORNERS REGION BY THIS TIME. ONLY SIMILARITY AMONG THE CURRENT ECMWF AND GFS IS THAT THIS WAVE WOULD BE OPEN AND PROGRESSIVE...THOUGH SIGNIFICANT DIFFERENCES EMERGE IN THE TIMING OF SAID WAVE AND HOW MUCH CP AIR IS DRAWN SOUTHWARD FOLLOWING ITS PASSAGE. WOULD STILL EXPECT A SEMI-ACTIVE DRYLINE TO UNFOLD NEAR THE FRINGES OF OUR EASTERN COUNTIES AS EARLY AS MON AND PERHAPS LINGERING INTO TUE UNDERNEATH AN INCREASINGLY UNSETTLED SWLY UPPER FLOW REGIME. THE GEFS MEAN AND EVEN THE CMC INDICATE SUCH A SCENARIO THAT AS OF YESTERDAY WAS FAVORED BY THE ECMWF...BUT WILL AWAIT LATER MODEL RUNS BEFORE COMMITTING TO ANY CHANGES STILL SO MANY PERIODS OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 46 32 68 43 76 / 40 10 0 0 0 TULIA 41 32 67 43 77 / 40 10 0 0 0 PLAINVIEW 41 34 68 44 77 / 30 10 0 0 0 LEVELLAND 48 34 70 46 81 / 30 10 0 0 0 LUBBOCK 43 35 70 45 79 / 30 10 0 0 0 DENVER CITY 51 34 70 47 82 / 20 10 0 0 0 BROWNFIELD 48 35 70 46 82 / 30 10 0 0 0 CHILDRESS 43 35 64 43 78 / 40 20 0 0 0 SPUR 41 35 68 45 81 / 30 10 0 0 0 ASPERMONT 43 37 66 44 80 / 30 10 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07/93/07
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1128 AM MDT WED APR 3 2013 .UPDATE... ISSUED AT 655 AM MDT WED APR 3 2013 UPDATED FORECAST TO REFLECT CURRENT CONDITIONS. REMOVED DRIZZLE/FOG FROM SOUTHERN I-25 CORRIDOR AS VISIBILITY HAS BEEN IMPROVING MOST AREAS. STILL SOME DENSE FOG AND PATCHY FREEZING DRIZZLE ACROSS EL PASO COUNTY THROUGH MID-MRNG AS WINDS HAVE YET TO GO NORTHERLY. ALSO ADDED A COUPLE HOURS OF LIGHT SNOW TO SAN LUIS VALLEY...WHERE ALAMOSA HAS BEEN REPORTING SNOW THE PAST HOUR. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 352 AM MDT WED APR 3 2013 UPPER LOW GRADUALLY SLIPPING EASTWARD ACROSS THE STATE EARLY THIS MORNING...AND SHOULD MOVE INTO THE SOUTHERN PLAINS BY THIS EVENING. STILL SOME RESIDUAL -SHRA/-SHSN/-FZDZ ACROSS THE AREA THIS MORNING...THOUGH RADAR TRENDS SUGGEST GRADUALLY DECREASING COVERAGE AND INTENSITY SINCE 09Z. WILL HOLD ON TO SOME LIGHT PRECIP THROUGH THE MORNING MOST AREAS...GRADUALLY ENDING FROM NW TO SE BY MIDDAY. MAY SEE A FEW SHOWERS REFIRE OVER THE MTS THIS AFTERNOON AS LAPSE RATES REMAIN FAIRLY STEEP...THOUGH PRECIP WILL BE VERY LIGHT. PERSISTENT -FZDZ AND FZFG OVER EL PASO COUNTY MAY LINGER THROUGH LATE MORNING...AS LATEST HRRR KEEPS WEAK SOUTHEAST WIND IN PLACE UNTIL 17Z. STILL THINK N-NW FLOW WILL DEVELOP THIS AFTERNOON AND GRADUALLY REMOVE ANY REMNANTS OF CLOUDS/FOG...THOUGH FAR SOUTHEAST PLAINS MAY HAVE TO WAIT UNTIL VERY LATE AFTERNOON TO SEE ANY SUN. WILL CONTINUE WITH REASONABLY MILD MAX TEMPS MOST LOCATIONS...THOUGH KEPT AREAS AROUND SPRINGFIELD COLDER THAN GUIDANCE DUE TO LINGERING CLOUDS. OVERNIGHT...WILL END PRECIP QUICKLY IN THE EVENING WITH LOSS OF HEATING...LEADING TO A MOSTLY CLEAR AND SEASONABLY COOL NIGHT MOST AREAS UNDER WEAK NORTHWEST FLOW. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 352 AM MDT WED APR 3 2013 ...SIGNIFICANT STORM POSSIBLE EARLY NEXT WEEK... LATTER HALF OF THIS WEEK LOOKS QUITE PLEASANT AS A TRANSITORY RIDGE CROSSES OUR AREA. THURSDAY MAY BE THE NICEST DAY...WITH DRY AND CLEAR CONDITIONS EXPECTED AREA-WIDE. WINDS SHOULD BE RELATIVELY LIGHT WITH THE RIDGE AXIS JUST WWD OF THE CWA. GIVEN THE LIGHT WINDS AND H7 TEMPS AROUND 4 DEGREES OR SO...HAVE GONE ON THE LOW SIDE OF MOS FOR TEMPS ON THE PLAINS...WITH HIGHS EXPECTED TO BE IN THE UPPER 60S TO AROUND 70 DEGREES. FRIDAY...FIRE WX ISSUES ARISE AS THE RIDGE SHIFTS TO THE EAST...AND ZONAL FLOW STRENGTHENS ACROSS THE CONTDVD. SHOULD SEE MARGINALLY CRITICAL FIRE WX CONDITIONS DEVELOP ACROSS THE PLAINS AS RH DROPS TO BELOW 15 PERCENT AND W WINDS BECOME RATHER GUSTY BY AFTERNOON. FOR THE WEEKEND...A WEAK SHORTWAVE TROUGH WILL MOVE THROUGH THE NRN ROCKIES...AND WILL LIKELY SPARK SCT-NMRS SHOWERS ACROSS THE MTS ESPECIALLY SAT AFTERNOON-EVE. MAIN CHANCES FOR PRECIP WILL BE N OF HIGHWAY 50 BOTH DAYS. TEMPS SHOULD REMAIN QUITE PLEASANT...IN THE MID 60S ACROSS THE PLAINS AND 50S FOR THE MTS AND HIGH VALLEYS. MAIN FOCUS IN THE EXTENDED CONTINUES TO BE THE LARGE SPRING STORM SYSTEM THAT IS EXPECTED TO AFFECT OUR AREA BY LATE IN THE WEEKEND THROUGH THE FIRST HALF OF NEXT WEEK. ENSEMBLE MEANS CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SRN ROCKIES FROM MON THROUGH WEDNESDAY. OP RUNS OF THE GFS AND ECMWF ALSO CONTINUE TO SHOW A DEEP TROUGH MOVING THROUGH THE SOUTHERN ROCKIES DURING THIS TIME FRAME. HOWEVER...SIGNIFICANT DIFFERENCES REMAIN IN THE EVOLUTION OF THE TROUGH PER THE GFS AND EC. THE 00Z EC IS MORE PROGRESSIVE...BUT SPLITS THE TROUGH...WITH THE MAIN ENERGY ARRIVING SUNDAY NIGHT THRU MONDAY...AND A SECONDARY LOW MOVING THROUGH NEXT WED. THE GFS BRINGS THE LOW THROUGH IN ONE PIECE...BUT IS SLOWER AND TARGETS THE MON NIGHT-TUESDAY TIME FRAME FOR THE HIGHEST POPS. BOTH MODELS PROG SIGNIFICANT QPF FOR SE CO...BETWEEN 1-2 INCHES OF LIQUID FOR THE SUN-WED TIME PERIOD. BOTH MODELS ALSO TARGET THE SERN MTS FOR THE HIGHEST PRECIP POTENTIAL. WHILE SNOW LEVELS LOOK TO REMAIN FAIRLY HIGH FOR THE BULK OF THIS EVENT...THE SE MTS ABOVE 7000 FEET WOULD PICK UP SIGNIFICANT SNOWFALL IN EITHER SCENARIO. THE ECMWF BRINGS IN UNUSUALLY COLD AIR BEHIND THE TROUGH BY WED...WITH H7 TEMPS BOTTOMING OUT NEAR MINUS 16 DEGREES. IF THIS OCCURS...THE HIGH TEMPS FOR NEXT WED MAY NEED TO BE SUBSTANTIALLY REDUCED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1121 AM MDT WED APR 3 2013 KCOS AND KPUB...EXPECT THE LOW CIGS TO CLEAR WITHIN THE NEXT HOUR OR SO. SAT PIX IMGY CONTINUES TO SHOW LOW CLOUDS DISSIPATING FROM NW/SE WITH TIME. WINDS AT KCOS THIS AFTERNOON MAY BE QUITE VARIABLE. HI RES SIMULATIONS SHOW A BOUNDARY EXTENDING E-W ACROSS W EL PASO COUNTY. WINDS N OF THE BOUNDARY ARE NORTHERLY AND SOUTH OF THE BOUNDARY THEY ARE SOUTHERLY. THIS BOUNDARY IS FCST TO WOBBLE DURING THE AFTERNOON AND THIS COULD CAUSE WINDS TO VARY SUBSTANTIALLY OVER THE KCOS TAF SITE. OVERALL...THE MODELS SHOW THE BOUNDARY STAYING N OF KCOS PROPER...AND FOR THIS REASON I PUT IN A PREDOMINANT SOUTHERLY WIND FOR KCOS THIS AFTERNOON. IN ADDITION...I CANNOT RULE OUT SOME LOCAL GROUND FOG LATER TONIGHT AT ALL 3 TAF SITES...BUT PROBABILITY IS TOO LOW FOR ME TO MENTION IT EXPLICITLY IN THE TAF. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...PETERSEN SHORT TERM...PETERSEN LONG TERM...ROSE AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS BILLINGS MT
314 PM MDT WED APR 3 2013 .SHORT TERM...VALID FOR THU AND FRI... COLD FRONT HAD PUSHED THROUGH THE FRONT RANGE OF MONTANA BY EARLY AFTERNOON AND IS CHUGGING ALONG PRETTY GOOD. I LIKE THE RAP MODELS TIMING WHICH SWITCHES BILLINGS WINDS TO THE NORTHEAST LATE THIS AFTERNOON AND SHERIDANS BY 8 PM. THE RAP ALSO BRINGS EASTERLY WIND INTO LIVINGSTON AT THAT POINT...BUT WE ARE LESS CONFIDENT IN THIS OCCURRING...AND BELIEVE THE COOLER AIR MIGHT STAY JUST EAST OF LIVINGSTON DOORSTEP. AT ANY RATE MODELS ARE GENERATING DECENT FRONTOGENESIS OVER OUR WESTERN ZONES LATE TODAY AND THERE APPEARS TO BE SOME MODEST CONVECTION DEVELOPING JUST UPSTREAM OF THIS AREA. SOME WEAK ENERGY CONTINUES TO MOVE ACROSS EAST CENTRAL MONTANA OVERNIGHT...SO WILL CONTINUE TO INCLUDE SOME LOW POPS AFTER MIDNIGHT. THURSDAY OUR FORECAST AREA WILL GENERALLY BE BETWEEN SYSTEMS WITH LOW AMPLITUDE RIDGING AND SURFACE TROUGHING DEVELOPING BEFORE EVENING. THE MAIN WEATHER FEATURE THURSDAY WILL BE THE BACKING UPPER FLOW BRINGING A NICE FETCH OF PACIFIC MOISTURE INTO THE INNER ROCKIES. SO WE EXPECT INCREASING CLOUD COVER TO LIMIT TEMPERATURES AND MIXING SOMEWHAT. BY THURSDAY NIGHT...WEAK ENERGY INVOLVED WITH THAT MOISTURE FETCH MAY SPREAD SOME LIGHT SHOWERS ACROSS THE REGION. HOWEVER THE MAIN PLAYER CONTINUES TO BE A LOW AMPLITUDE SHORT WAVE PROGGED TO CROSS OUR FORECAST AREA FRIDAY. MODELS AGREE THAT Q VECTOR FORCING WILL BE RIGHT OVER OUR ZONES FRIDAY AFTERNOON WITH DECENT CAPE ON THE ORDER FROM 200-400 JL/KG. I CONTINUED TO NUDGE THE POPS UP FOR FRIDAY AFTERNOON IN MANY LOCATIONS AND WENT CATEGORICAL IN THE HIGH COUNTRY. THE GFS LINGERS QPF OVER OUR FORECAST AREA WELL INTO FRIDAY NIGHT...BUT THE OVERALL CONSENSUS OF MODELS GENERALLY EXIT THIS FORCING TO THE EAST IN THE EVENING. THIS SEEMS MORE LIKELY GIVEN THE GOOD CONVERGENT/DIVERGENT COUPLET...SO TRENDED OUR POPS LOWER OVERNIGHT. BT .LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED... FAIRLY ACTIVE AND SPRING-LIKE WEATHER PATTERN SHAPING UP FOR THE EXTENDED PERIOD...THOUGH LATEST MODELS HAVE SHIFTED A BIT FOR THE MON/TUE TIME FRAME. SATURDAY STILL LOOKING FAIRLY QUIET WITH RIDGING BEHIND LATE FRIDAY WAVE. HAVE REDUCED POPS FOR ALL BUT OUR WEST...WHICH SHOULD BEGIN TO SEE INCREASED SHOWER ACTIVITY BY AFTERNOON...AND PER WESTERLY DOWNSLOPE WINDS HAVE ALSO RAISED TEMPS A FEW DEGREES. SHOULD SEE HIGHS INTO THE LOWER/MID 60S. MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH TIMING A SHORTWAVE THROUGH THE REGION SATURDAY NIGHT. WITH INCREASING CONFIDENCE HAVE RAISED POPS A BIT MORE...TO LIKELY IN CENTRAL AND EAST PARTS AWAY FROM THE DOWNSLOPING WESTERN FOOTHILLS. AIRMASS LOOKS TO BE TOO WARM FOR ANYTHING BUT RAIN SHOWERS AT OUR LOWER ELEVATIONS...WITH A POSSIBLE EXCEPTION IN OUR FAR NE WHERE LOW LEVEL EAST WINDS MAY KEEP 850MB TEMPS NEAR ZERO. SO WILL KEEP A RAIN/SNOW MIX WITH JUST A LITTLE ACCUMULATION FROM MILES CITY TO BAKER...BUT THE BETTER SNOW POTENTIAL REALLY SHOULD BE NORTH AND NORTHEAST OF OUR CWA. SYSTEM WILL EXIT QUICKLY INTO THE DAKOTAS AROUND 12Z SUNDAY. NEXT PACIFIC ENERGY WILL BEGIN TO INFLUENCE OUR WEST BY SUNDAY AFTERNOON OR NIGHT...SOME TIMING ISSUES EXIST HERE. THEN...AS PREVIOUSLY MENTIONED...MODELS ARE BEGINNING TO PAINT A DIFFERENT PICTURE WITH EVOLUTION OF THIS SYSTEM INTO MON/TUE. FLOW IN THE EASTERN PACIFIC NOW EXPECTED TO BE A BIT FLATTER...WITH AMPLIFICATION OVER THE WESTERN CONUS SHIFTED A BIT EAST. THUS... PER LATEST TRENDS...A LARGE CLOSED LOW OVER THE GREAT BASIN TO 4-CORNERS REGION NOW LOOKS LESS LIKELY...WHICH LEAVES A WNW FLOW WITH LOWER HEIGHTS OVER OUR REGION AS ENERGY DRIVES TO THE CENTRAL ROCKIES AND MIDDLE PLAINS. COULD STILL SEE SOME WET SNOW IMPACTS IN OUR AREA SOMETIME IN THE SUNDAY NIGHT INTO TUESDAY TIME FRAME...AND BOTH THE GFS AND EC SHOW 850MB TEMPS NEAR OR SLIGHTLY BELOW ZERO...BUT OVERALL POTENTIAL APPEARS LOWER NOW. PROGRESSIVE SHORTWAVE ENERGY IN LOW HEIGHT REGIME AND LOW LEVEL UPSLOPE FLOW ALL COMBINE TO WARRANT ABOVE CLIMO POPS FOR US NONETHELESS. WILL TAPER POPS TO BELOW CLIMO...SLIGHT CHANCE...BY WEDNESDAY AS MODEL CONSENSUS IS FOR RISING HEIGHTS WITH RIDGE BEGINNING TO BUILD OVER THE PAC NW BY THEN. AS FOR TEMPERATURES...ABOVE NORMAL SATURDAY SHOULD COOL TO NEAR NORMAL SUNDAY AND BELOW NORMAL MONDAY AND TUESDAY. COULD SEE A RETURN TO NEAR OR ABOVE NORMAL TEMPS BY THE MIDDLE OF NEXT WEEK... AND HAVE ADJUSTED GRIDS ACCORDINGLY. JKL && .AVIATION... A CANADIAN COLD FRONT IS PUSHING SOUTHWARD THROUGH THE AREA THIS AFTERNOON...CAUSING GUSTY NW-N-NE WINDS ACROSS THE LOWER ELEVATIONS...WITH GUSTS TO 25 KTS UNTIL SUNSET. EXPECT ISOLATED TO SCATTERED SHOWERS TO DEVELOP ALONG THIS FRONTAL BOUNDARY FROM KLVM TO KBIL AND KSHR THROUGH AROUND 04Z...WITH DRYING ANTICIPATED LATER TONIGHT. LOCALIZED MVFR IS POSSIBLE WITH THE SHOWER ACTIVITY. VFR CONDITIONS WILL PREVAIL ACROSS THE AREA LATE TONIGHT AND THURSDAY. JKL && .PRELIMINARY POINT TEMP/POPS... THU FRI SAT SUN MON TUE WED ----------------------------------------------------------- BIL 034/064 043/064 038/063 038/057 032/046 029/048 030/056 20/B 37/T 32/W 52/W 35/W 42/W 22/W LVM 033/064 039/058 033/061 031/055 029/044 028/046 028/055 31/B 26/T 24/W 53/W 35/J 32/W 22/W HDN 033/065 041/068 038/065 036/059 031/047 029/049 028/054 20/B 37/T 32/W 62/W 35/W 42/W 22/W MLS 031/057 038/067 038/061 035/055 029/045 027/045 026/049 32/W 24/T 31/B 62/W 24/W 42/W 22/W 4BQ 031/064 040/066 038/062 036/056 032/046 028/044 024/046 21/B 14/T 41/B 63/W 24/W 43/W 22/W BHK 027/050 032/061 035/055 031/050 027/041 023/041 023/043 33/W 13/T 31/B 64/W 33/W 33/J 22/W SHR 032/064 039/066 035/061 033/056 030/045 027/045 027/051 20/B 14/T 31/B 32/W 35/W 43/W 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1248 PM CDT WED APR 3 2013 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 314 AM CDT WED APR 3 2013 THE RAP...NAM AND GFS ARE SUGGESTING SUFFICIENT LOW AND MID LEVEL CLOUDINESS ACROSS SRN NEB TO HOLD TEMPS IN THE 50S TODAY. AT THE SAME TIME SOUTH AND SOUTHWEST WINDS WILL RECIRCULATE COOL AIR NORTH FROM THE HIGH PRESSURE SYSTEM ACROSS THE MID SOUTH. SO THE RAP 21Z TEMPS WERE USED AS THE BASIS FOR TODAYS HIGHS WHICH IS CLOSE TO THE GUIDANCE DATA SETS. IF FULL SUN ARRIVES OR EVEN JUST HIGH LEVEL CLOUDINESS...HIGHS COULD BE A FEW DEGREES WARMER. THE BEST GUESS ON TONIGHTS LOWS IS FOR THE CLOUDS TO DEPART WITH WEAK SFC WINDS DEVELOPING AHEAD OF A COLD FRONT MOVING THROUGH SOUTH DAKOTA WHICH WOULD SUPPORT SOME RADIATIONAL COOLING ACROSS NEB. LOWS IN THE UPPER 20S TO MID 30S APPEARS TO BE THE BEST FORECAST. ADDITIONAL COOLING FROM THE DROUGHT CONDITIONS COULD PUSH LOWS FURTHER. THE REST OF THE FCST IS WELL BEHAVED. WINDS COULD REACH THE BREEZY CATEGORY BUT RELATIVE HUMIDITY WILL RUN 25 TO 30 PERCENT. THE RAP SUGGESTED LOWER RH ACROSS FAR NORTHWEST NEB AS THE FRONT NOSES SOUTH LATE THIS AFTN BUT AT THE SAME TIME WINDS WEAKEN. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 314 AM CDT WED APR 3 2013 12Z THURSDAY AND BEYOND. TWO MAIN CONCERNS GOING IN THE EXTENDED PERIOD. FIRST BEING THE POTENTIAL FOR FIRE HEADLINES ON FRIDAY...THEREAFTER THE FOCUS TURNS TO THE DEVELOPMENT OF A WESTERN CONUS TROUGH...WHICH MAY BRING PERIODS OF WIDESPREAD PRECIPITATION BACK ACROSS THE FORECAST AREA LATE THIS WEEKEND THROUGH EARLY NEXT WEEK. SURFACE TEMPERATURES WILL SLOWLY MODERATE FROM WEST TO EAST ON THURSDAY AS SURFACE HIGH PRESSURE SLOWLY BUILDS EAST ACROSS THE NORTHERN PLAINS AND ALLOWS FOR A RETURN SOUTHERLY FLOW. A TIGHT GRADIENT IS EXPECTED IN THE TEMPERATURE FIELD...WITH HIGHS POSSIBLY APPROACHING 70 ACROSS SOUTHWEST NEBRASKA...BUT READINGS OF ONLY THE LOW TO MID 50S OVER NORTH CENTRAL NEBRASKA. FOR FRIDAY...THE NORTHERN PLAINS HIGH WILL BE LOCATED OVER THE GREAT LAKES REGION WITH STRONG SOUTHERLY RETURN FLOW TARGETING THE ENTIRE FORECAST AREA. WITH DEEPENING LOW PRESSURE ON THE LEE OF THE ROCKIES...A TIGHT PRESSURE GRADIENT IS EXPECTED...WITH THE POTENTIAL FOR WIND GUSTS IN EXCESS OF 25 MPH. MEANWHILE SFC TEMPERATURE AND DEW POINT SPREADS WILL APPROACH 40 F...WHICH SHOULD LEAD TO LOCALIZED AREAS OF SUB 20 PERCENT RH. GIVEN THAT GREEN UP HAS NOT YET OCCURRED...LOCALIZED RED FLAG CONDITIONS ARE POSSIBLE. UNCERTAINTY REMAINS IF THE RED FLAG CRITERIA WIND GUSTS WILL BE CO-LOCATED WITHIN THE CRITICAL RH FIELD. AT THIS TIME...IT APPEARS THAT THE STRONGEST GUSTS SHOULD OCCUR OVER EASTERN PORTIONS OF THE CWA...WHERE THE SOUTHERLY FLOW SHOULD HELP PUSH TD/S UP NEAR 40...WHICH WOULD KEEP MINIMUM RH IN THE 20-30 PERCENT RANGE. THE DRIEST AIR IS EXPECTED ACROSS THE WESTERN HALF OF THE CWA...SLIGHTLY REMOVED FROM THE STRONGEST GUSTS. OBVIOUSLY THERE IS STILL TIME TO HAMMER OUT THE DETAILS...BUT GIVEN A FAVORABLE FIRE WX PATTERN /RIDGE BREAKDOWN/ AND THE FACT THAT WIND SHIFT IS EXPECTED LATE AFTERNOON/EVENING AS A SURFACE TROUGH AND COLD FRONT ADVANCE EAST ACROSS THE CWA...ITS SAFE TO SAY AT THIS JUNCTURE THAT ELEVATED FIRE CONCERNS ARE CERTAINLY WARRANTED...WILL CONTINUE TO MONITOR. ALSO OF CONCERN...PROXIMITY SOUNDINGS INDICATE WEAK INSTABILITY ALONG THE FRONTAL PASSAGE...BUT DRY LOWER LEVELS...A FEW DRIER CG STRIKES COULD OCCUR. OTHERWISE HIGH TEMPERATURES WILL COOL SOME TEN DEGREES FROM THE MID 70S DOWN TO THE UPPER 50S TO MID 60S ON SATURDAY. LOWS FRIDAY AND SATURDAY MORNING WILL BE MILD RELATIVELY SPEAKING...WITH LOWS IN THE 30S FRIDAY...AND LOWS IN THE 40S SATURDAY MORNING. ATTENTION NOW TURNS TO THE MYRIAD OF POTENTIAL WEATHER FOR LATE SUNDAY THROUGH EARLY NEXT WEEK...BUT UNFORTUNATELY THE 03.00Z RUN OF THE MODELS FAILED TO INCREASE FORECAST CONFIDENCE AS SIGNIFICANT DIFFERENCES IN TIMING AND STRENGTH OF THE WESTERN CONUS TROUGH EXISTS. THE GENERAL IDEA IS THAT A SHORTWAVE WILL CROSS THE CENTRAL/NORTHERN PLAINS ON SUNDAY PROVIDING FOR SHOWERS AND/OR TSTMS...THEN THE MEAN TROUGH WILL DEVELOP OVER THE ROCKIES AND SLOWLY ADVANCE OUT ONTO THE PLAINS EARLY NEXT WEEK. THE EC SOLUTION CONTINUES TO ADVERTISE ENOUGH COLD AIR ON THE BACK SIDE OF THE MAIN H5 LOW TO ALLOW FOR SNOW ACCUMULATIONS...WHICH MAY BE SIGNIFICANT. ALSO OF NOTE...THE EC DEVELOPS H85 WINDS IN EXCESS OF 60KTS EARLY TUESDAY ACROSS EASTERN PORTIONS OF THE CWA. THE EURO HAS SHOWN A COLD BIAS WITH IT/S LAST STORM THAT AFFECTED OUR CWA...SO THE AMOUNT OF COOLING IS SUSPECT. THE GFS IS SHOWING A BIT MORE OF A SOUTHERLY TRACK OF THE MEAN TROUGH...AND IS LESS NEGATIVELY TILTED...BUT THE GFS ENSEMBLE MEAN GIVES SUPPORT TO THE EC SOLUTION. AS STATED PREVIOUSLY...CONFIDENCE IN ANY PARTICULAR SOLUTION IS LOW...THUS WILL MAINTAIN 40 PERCENT POPS OR LESS THROUGH THE EVENT AND KEEP THE GENERAL IDEA OF SHOWERS OF RAIN INITIALLY...THEN POSSIBLY CHANGING && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1243 PM CDT WED APR 3 2013 UPPER LEVEL LOW PRESSURE SYSTEM CONTINUES TO MOVE SLOWLY EAST ACROSS KS. SOME MID AND HIGH LEVEL CLOUDS HAVE SPREAD INTO SOUTHWEST NEBRASKA WITH THIS SYSTEM. OTHERWISE A BRISK SOUTH TO SOUTHWEST WIND...WITH GUSTS OF 25 TO 30 KTS WILL CONTINUE THROUGH THE AFTERNOON. WINDS WILL DECREASE TONIGHT WITH CONTINUE VFR. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...JACOBS AVIATION...TAYLOR
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1227 PM CDT WED APR 3 2013 .UPDATE... SEE UPDATED AVIATION DISCUSSION BELOW. LATE MORNING UPDATE TODAY INCLUDED INCREASING WIND SPEEDS AND ENHANCING A CORRIDOR OF STRONGER WINDS ALONG AND JUST EAST OF THE EASTERN SLOPE OF THE PRAIRIE COTEAU. LEFT EVERYTHING ELSE AS IS SINCE THERMAL ADVECTION SUGGESTS WE SHOULD GET CLOSE TO ADVERTISED HIGH TEMPS TODAY...AND LATEST HRRR AND 12Z SPC WRF CONTINUES TO HINT AT ISOLATED TO WIDELY SCATTERED WEAK CONVECTION THIS AFTERNOON THROUGH EARLY THIS EVENING. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH FRIDAY MAIN CONCERNS THROUGH THE PERIOD ARE TEMPERATURES AND PCPN CHANCES. FOR TODAY THE REGION SHOULD BASK IN A RELATIVELY MILD AIRMASS AS SOUTHWEST BREEZES KICK IN AHEAD OF AN ADVANCING FRONT. MODEL H85 TEMPS ARE EXPECTED TO RANGE FROM 5 TO 10 DEGREES C WHICH SUGGESTS THE SOUTHWEST CWA SHOULD GET CLOSE TO 70 PROVIDED MIXING IS SUFFICIENT. THE NORTHEAST CWA REMAINS PROBLEMATIC AS SNOW IS STILL COVERING A MAJOR PORTION OF THE GLACIAL LAKES AREA. FOR NOW AM GOING CLOSE TO A MODEL BLEND FOR THAT REGION. MEANWHILE THE MODELS CONTINUE TO CRANK OUT SOME LIGHT PCPN JUST BEHIND THE FRONT LATE TODAY AND TNT AS IT CROSSES THE CWA. TIME HEIGHTS AND SOUNDINGS INDICATE SOME LOWER LEVEL DRY AIR THAT WOULD HAVE TO BE OVERCOME FOR MUCH IN THE WAY OF MEASURABLE PCPN. SO...SLIGHT CHANCE POPS LOOK FINE. IT SHOULD THEN BE MAINLY DRY FOR THURSDAY THROUGH FRIDAY BEFORE THE NEXT SYSTEM MOVES IN LATER ON FRIDAY. THAT SYSTEM SHOULD BRING SOME WAA PCPN TO THE NORTHERN PARTS OF THE STATE FRIDAY INTO FRIDAY NIGHT. FOR NOW IT APPEARS TO BE MOSTLY RAIN GIVEN EXPECTED TEMPERATURES AND PROGGED PARTIAL THICKNESS. .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY FAIRLY ACTIVE PATTERN LOOKS TO BE SETTING UP ACROSS THE NORTHERN PLAINS WITH THE FIRST WAVE OF INTEREST MOVING THROUGH THE AREA FRIDAY NIGHT AND SATURDAY. MODELS IN GENERAL AGREEMENT IN MOVING THE SFC LOW EASTWARD ACROSS SOUTHERN SOUTH DAKOTA. CONFIDENCE IS INCREASING IN THERE BEING PRECIP NORTH OF THE WARM FRONT ACROSS THE NORTHEASTERN CWA. HAVE INCREASED POPS A BIT. AS THE SFC LOW MOVES INTO MN BY SATURDAY...COLDER AIR WRAPS INTO THE CWA...ALTHOUGH MODELS ARE STILL VARYING QUITE A BIT IN THEIR THERMAL PROFILES ON THE BACK SIDE OF THIS SYSTEM. EC IS RATHER WARM WHILE GFS IS COOLER. FOR RIGHT NOW HAVE JUST ALL RAIN IN THE FORECAST BUT IF MODELS TURN A BIT COLDER...COULD ALSO SEE SOME SNOW MIXED IN AS WELL BY SATURDAY MORNING. IT LOOKS LIKE ANOTHER DECENT LOOKING WAVE MOVES THROUGH ON SUNDAY...WITH FAIR AGREEMENT AMONGST THE MODELS. GENERALLY ACCEPTED ALLBLEND POP GRIDS FOR THIS SYSTEM. HEADING INTO EARLY NEXT WEEK THINGS BECOME MUCH MORE UNCERTAIN. ALLBLEND POPS MAY BE OVERDONE INTO EARLY NEXT WEEK AS MODELS ARE SHOWING SFC HIGH RIDGING ACROSS THE AREA...BUT ALLBLEND GIVING POPS. MAY NEED TO BACK OFF MORE ON THIS. MODELS HAVE TRENDED A BIT FURTHER SOUTH WITH ANOTHER POTENTIAL STORM SYSTEM EARLY NEXT WEEK. && .AVIATION... 18Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL THROUGH THE TAF FORECAST PERIOD. BREEZY SOUTHERLY SFC WINDS WILL CONTINUE ACROSS THE REGION THIS AFTERNOON. A COLD FRONT WILL SWEEP SOUTHEAST ACROSS THE AREA THIS AFTERNOON AND EVENING...SWITCHING SFC WINDS TO A NORTHERLY DIRECTION. SOME LIGHT SHOWERS ARE POSSIBLE AHEAD OF THIS FRONT. CURRENTLY A LINE STRETCHES FROM BISMARCK TO LEMMON PROGRESSING SOUTHEASTWARD. NO IMPACTS ARE EXPECTED TO TAFS WITH THESE SHOWERS. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...WISE SHORT TERM...TDK LONG TERM...TMT AVIATION...WISE WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1222 PM CDT WED APR 3 2013 .UPDATE... LATE MORNING UPDATE TODAY INCLUDED INCREASING WIND SPEEDS AND ENHANCING A CORRIDOR OF STRONGER WINDS ALONG AND JUST EAST OF THE EASTERN SLOPE OF THE PRAIRIE COTEAU. LEFT EVERYTHING ELSE AS IS SINCE THERMAL ADVECTION SUGGESTS WE SHOULD GET CLOSE TO ADVERTISED HIGH TEMPS TODAY...AND LATEST HRRR AND 12Z SPC WRF CONTINUES TO HINT AT ISOLATED TO WIDELY SCATTERED WEAK CONVECTION THIS AFTERNOON THROUGH EARLY THIS EVENING. && .PREVIOUS DISCUSSION... .SHORT TERM...TODAY THROUGH FRIDAY MAIN CONCERNS THROUGH THE PERIOD ARE TEMPERATURES AND PCPN CHANCES. FOR TODAY THE REGION SHOULD BASK IN A RELATIVELY MILD AIRMASS AS SOUTHWEST BREEZES KICK IN AHEAD OF AN ADVANCING FRONT. MODEL H85 TEMPS ARE EXPECTED TO RANGE FROM 5 TO 10 DEGREES C WHICH SUGGESTS THE SOUTHWEST CWA SHOULD GET CLOSE TO 70 PROVIDED MIXING IS SUFFICIENT. THE NORTHEAST CWA REMAINS PROBLEMATIC AS SNOW IS STILL COVERING A MAJOR PORTION OF THE GLACIAL LAKES AREA. FOR NOW AM GOING CLOSE TO A MODEL BLEND FOR THAT REGION. MEANWHILE THE MODELS CONTINUE TO CRANK OUT SOME LIGHT PCPN JUST BEHIND THE FRONT LATE TODAY AND TNT AS IT CROSSES THE CWA. TIME HEIGHTS AND SOUNDINGS INDICATE SOME LOWER LEVEL DRY AIR THAT WOULD HAVE TO BE OVERCOME FOR MUCH IN THE WAY OF MEASURABLE PCPN. SO...SLIGHT CHANCE POPS LOOK FINE. IT SHOULD THEN BE MAINLY DRY FOR THURSDAY THROUGH FRIDAY BEFORE THE NEXT SYSTEM MOVES IN LATER ON FRIDAY. THAT SYSTEM SHOULD BRING SOME WAA PCPN TO THE NORTHERN PARTS OF THE STATE FRIDAY INTO FRIDAY NIGHT. FOR NOW IT APPEARS TO BE MOSTLY RAIN GIVEN EXPECTED TEMPERATURES AND PROGGED PARTIAL THICKNESS. .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY FAIRLY ACTIVE PATTERN LOOKS TO BE SETTING UP ACROSS THE NORTHERN PLAINS WITH THE FIRST WAVE OF INTEREST MOVING THROUGH THE AREA FRIDAY NIGHT AND SATURDAY. MODELS IN GENERAL AGREEMENT IN MOVING THE SFC LOW EASTWARD ACROSS SOUTHERN SOUTH DAKOTA. CONFIDENCE IS INCREASING IN THERE BEING PRECIP NORTH OF THE WARM FRONT ACROSS THE NORTHEASTERN CWA. HAVE INCREASED POPS A BIT. AS THE SFC LOW MOVES INTO MN BY SATURDAY...COLDER AIR WRAPS INTO THE CWA...ALTHOUGH MODELS ARE STILL VARYING QUITE A BIT IN THEIR THERMAL PROFILES ON THE BACK SIDE OF THIS SYSTEM. EC IS RATHER WARM WHILE GFS IS COOLER. FOR RIGHT NOW HAVE JUST ALL RAIN IN THE FORECAST BUT IF MODELS TURN A BIT COLDER...COULD ALSO SEE SOME SNOW MIXED IN AS WELL BY SATURDAY MORNING. IT LOOKS LIKE ANOTHER DECENT LOOKING WAVE MOVES THROUGH ON SUNDAY...WITH FAIR AGREEMENT AMONGST THE MODELS. GENERALLY ACCEPTED ALLBLEND POP GRIDS FOR THIS SYSTEM. HEADING INTO EARLY NEXT WEEK THINGS BECOME MUCH MORE UNCERTAIN. ALLBLEND POPS MAY BE OVERDONE INTO EARLY NEXT WEEK AS MODELS ARE SHOWING SFC HIGH RIDGING ACROSS THE AREA...BUT ALLBLEND GIVING POPS. MAY NEED TO BACK OFF MORE ON THIS. MODELS HAVE TRENDED A BIT FURTHER SOUTH WITH ANOTHER POTENTIAL STORM SYSTEM EARLY NEXT WEEK. && .AVIATION... 12Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CONDITIONS WILL PREVAIL THROUGH THE TAF FORECAST PERIOD. BREEZY SOUTHERLY SFC WINDS WILL DEVELOP ACROSS THE REGION TODAY. A COLD FRONT WILL THEN SWEEP SOUTHEAST ACROSS THE AREA THIS EVENING...SWITCHING SFC WINDS TO A NORTHERLY DIRECTION. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...DORN SHORT TERM...TDK LONG TERM...TMT AVIATION...TMT WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1244 PM CDT WED APR 3 2013 .AVIATION... CONDITIONS AT KLBB ARE EXPECTED TO IMPROVE THIS AFTERNOON AS DRY SLOT ROTATING ACROSS THE UPPER LEVEL LOW TO OUR NORTHWEST HELPS TO DRY LOW LEVEL CONDITIONS. CLOUDS ARE EXPECTED TO HANG AROUND KCDS THOUGH SOME UNCERTAINTY EXISTS IN THE FLIGHT CATEGORY AS IFR CONDITIONS PERSIST JUST NORTH OF THAT TERMINAL. INTO THE OVERNIGHT HOURS...CLEARING SKIES AND LIGHT WINDS WILL LIKELY HELP FOG FORMATION. HAVE GONE FAIRLY CONSERVATIVELY ON VISIBILITY FOR NOW THOUGH VLIFR IS POSSIBLE. && .PREV DISCUSSION... /ISSUED 634 AM CDT WED APR 3 2013/ AVIATION... IFR CONDITIONS LIKELY TO PERSIST INTO THE AFTN HOURS AT BOTH TAF SITES. KLBB MAY SEE SOME LIFTING OF THE CIGS THIS AFTN THEN PROBABLY SCATTER OUT THIS EVENING. KCDS LOOKS LESS LIKELY TO SEE MUCH IMPROVEMENT UNTIL LATE IN THE TAF PERIOD OR BEYOND. DEEP MOISTURE NOT AS RICH AS EXPECTED WHICH WILL RESULT IN GREATLY REDUCED PRECIP CHANCES TODAY. BOTH TAF SITES...KCDS MORESO THAN KLBB...COULD SEE SOME LIGHT SHOWERS BUT CHANCES NOW LOOK TO SLIM TO MENTION GIVEN RESTRICTIONS ON PROB30 GROUP WITHIN FIRST 9 HOURS OF TAF PERIOD. PREV DISCUSSION... /ISSUED 410 AM CDT WED APR 3 2013/ SHORT TERM... MAJOR CHANGE TO THE FCST THIS MORNING IS TO CONSIDERABLY LOWER POPS ACROSS THE AREA. UNFORTUNATELY...PREVIOUS MODEL RUNS MISSED THE EXTENSIVE MCS THAT MOVED ACROSS AREAS FROM NW TEXAS TO SOUTH TEXAS. IT APPEARS THAT THIS MCS WILL LEAVE THE FCST AREA STARVED OF DEEP MOISTURE AND THUS THE LIFT ASSOCIATED WITH THE LOW OVER CNTL COLORADO WILL LIKELY PRODUCE MUCH LESS PRECIP THAN PREVIOUSLY EXPECTED. THE 00Z MODEL SUITE MISSED THIS CRITICAL ELEMENT RESULTING IN TOO MUCH WIDESPREAD QPF AND MOS GUIDANCE WHOSE POPS APPEAR TO BE TOO HIGH. HAVE TRENDED THE FCST MUCH CLOSER TO THE 06Z RUC WHICH DID INITIALIZE THE MCS AND SUBSEQUENTLY SEEMS TO HAVE A BETTER HANDLE ON POSSIBLE PRECIP TODAY. THAT POSSIBILITY THEN SEEMS TO FOCUS ON POTENTIAL FOR SCATTERED LIGHT SHOWERS MAINLY ACROSS THE NRN ZONES IN AN AREA OF LIFT JUST AHEAD AND SOUTH OF THE TRACK OF THE UPPER LOW. PRECIP HAS BEEN HARD TO COME BY VCNTY OF THE LOW WITH SOME LIGHT RA AND SN IN SRN COLORADO AND SOME LIGHT RA SOUTH OF KABQ IN CNTL NM AS A JET STREAK ROTATES AROUND THE BASE OF THE TROUGH. IN THE NEAR TERM EVEN DRIZZLE CHANCES APPEAR TO BE ON THE WANE AS A MID LEVEL DRY SLOT AND SOME APPARENT DOWNWARD MOTION TO THE REAR OF THE CNTL TX MCS WORK IN ACROSS THE AREA. COULD SEE DRIZZLE TRY TO REDEVELOP A LITTLE LATER THIS MORNING ONCE SOME WEAK LIFT WORKS BACK OVER THE AREA...BUT EVEN MEASURABLE PRECIP FROM THIS ELEMENT LOOKING VERY UNLIKELY. TEMP FCST WILL BE TRICKY FOR THIS AFTN WITH SOME UNCERTAINTY REGARDING HOW MUCH LOW STRATUS WILL REMAIN IN PLACE OR THIN. 00Z MODELS APPEAR TO BE TOO AGGRESSIVE WITH WARMING AND HAVE TRENDED TEMPS A BIT BELOW MOS. HOWEVER...ANY LATE DAY CLEARING OR LIFTING OF CEILINGS AS THE CENTER OF THE LOW MOVES ACROSS THE SRN PANHANDLE WOULD SEE TEMPS APPROACH THAT PROGGED BY MOS. THIS WOULD BE MOST LIKELY TO OCCUR ACROSS THE SWRN ZONES. MOVING INTO TONIGHT...LESSENING RAIN CHANCES SHOULD SHIFT EAST OF THE AREA BY EARLY EVENING. MODELS KEEP LOW LEVEL MOISTURE LEVELS PRETTY STEADY WHILE DROPPING WINDS OFF TO BECOME VERY LIGHT. SOME HINTING OF FOG POTENTIAL LATE TONIGHT...AND IF MORE RAIN HAD FALLEN IN THE LAST 24 HOURS OR MORE FALLS THAN EXPECTED OVER THE NEXT SEVERAL HOURS WOULD BE MORE INCLINED TO MENTION AREAS OF FOG IN THE FCST. STILL A BIT TOO MUCH UNCERTAINTY HERE AND WILL LET NEXT SHIFT REEVALUATE THAT POTENTIAL. LONG TERM... A RETURN TO MORE SEASONABLE TEMPS REMAINS ON TRACK BEGINNING TOMORROW AS THE SOUTH PLAINS SHAKES THE RECENT FORAY OF MODIFIED CANADIAN AIR. A BEVERAGE SUCH AS CANADA DRY WOULD PROVE FITTING FOR THE NEXT SEVERAL DAYS AS TRANSIENT RIDGING ALOFT CARRIES A DOME OF VERY MILD AND DRY AIR EAST OVER MUCH OF THE SOUTH PLAINS. BY FRIDAY...WE SHOULD SEE A PALTRY DRYLINE EVOLVE IN THE ROLLING PLAINS BEHIND THE DEPARTING SURFACE HIGH. QUALITY RETURN FLOW HOWEVER IS NOT EXPECTED UNTIL SATURDAY AT WHICH POINT STRONGER WESTERLY WINDS ALOFT BEHIND THE UPPER RIDGE WILL SHUNT MUCH OF THIS SHALLOW MOISTURE OUT OF ALL BUT OUR FAR EASTERN COLUMN OF COUNTIES. A MINOR SHORT WAVE TROUGH IS STILL PROGGED TO SLIDE THROUGH THIS STRONGER WESTERLY FLOW BY SAT NIGHT/SUN MORNING ACCOMPANIED BY PERHAPS EVEN DRIER AND WARMER CONDITIONS ON SUNDAY...BUT WILL STICK WITH SLIGHTLY COOLER CONDITIONS AS A COLD FRONT WILL BE FOUND EDGING PERILOUSLY CLOSE TO OUR NRN COUNTIES IN THE WAKE OF THIS UPPER IMPULSE. BY EARLY NEXT WEEK...NO CHANGES ARE WARRANTED ATTM AS MODELS ARE NOW IN MORE DISAGREEMENT THAN 24 HOURS AGO. WPC CONTINUES TO FAVOR A SLOWER AND DEEPER LONGWAVE TROUGH EVOLVING IN THE GREAT BASIN AND FOUR CORNERS REGION BY THIS TIME. ONLY SIMILARITY AMONG THE CURRENT ECMWF AND GFS IS THAT THIS WAVE WOULD BE OPEN AND PROGRESSIVE...THOUGH SIGNIFICANT DIFFERENCES EMERGE IN THE TIMING OF SAID WAVE AND HOW MUCH CP AIR IS DRAWN SOUTHWARD FOLLOWING ITS PASSAGE. WOULD STILL EXPECT A SEMI-ACTIVE DRYLINE TO UNFOLD NEAR THE FRINGES OF OUR EASTERN COUNTIES AS EARLY AS MON AND PERHAPS LINGERING INTO TUE UNDERNEATH AN INCREASINGLY UNSETTLED SWLY UPPER FLOW REGIME. THE GEFS MEAN AND EVEN THE CMC INDICATE SUCH A SCENARIO THAT AS OF YESTERDAY WAS FAVORED BY THE ECMWF...BUT WILL AWAIT LATER MODEL RUNS BEFORE COMMITTING TO ANY CHANGES STILL SO MANY PERIODS OUT. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 46 32 68 43 76 / 40 10 0 0 0 TULIA 41 32 67 43 77 / 40 10 0 0 0 PLAINVIEW 41 34 68 44 77 / 30 10 0 0 0 LEVELLAND 48 34 70 46 81 / 30 10 0 0 0 LUBBOCK 43 35 70 45 79 / 30 10 0 0 0 DENVER CITY 51 34 70 47 82 / 20 10 0 0 0 BROWNFIELD 48 35 70 46 82 / 30 10 0 0 0 CHILDRESS 43 35 64 43 78 / 40 20 0 0 0 SPUR 41 35 68 45 81 / 30 10 0 0 0 ASPERMONT 43 37 66 44 80 / 30 10 0 0 0 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/26