Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/28/12


AREA FORECAST DISCUSSION
NWS PUEBLO CO
337 PM MDT SAT MAY 26 2012 .SHORT TERM... (TONIGHT AND SUNDAY) MAIN CONCERNS ARE THE WINDS AND ASSOCIATED FIRE WEATHER CONCERNS...AND THE POTENTIAL FOR THUNDERSTORMS NEAR THE KANSAS BORDER. A STRONG UPR LOW IS CURRENTLY LIFTING NORTHEASTWARD AND IS EXPECTED TO MOVE ACRS ERN ID AND WRN WY TONIGHT...AND MOVING INTO EASTERN MT BY SUN AFTERNOON. THE STRONG WINDS OVR THE AREA WL CONTINUE INTO THE EARLY EVENING HOURS AND WL THEN DECREASE. HOWEVER...MANY AREAS WL CONTINUE TO SEE BREEZY CONDITIONS THRU MUCH OF THE NIGHT AS THE WINDS BECOME MORE WESTERLY AS THAT UPR LOW TRACKS NORTHEAST. THE STRONG WINDS...AND LOW HUMIDITIES AND DRY FUELS IN TELLER AND FREMONT COUNTIES AND OVER THE RAMPART RANGE WL CONTINUE TO PRODUCE CRITICAL FIRE CONDITIONS UNTIL LATE EVENING IN THESE AREAS...SO THE RED FLAG WARNING WILL REMAIN IN PLACE. THIS AFTERNOON...DEW POINTS NR THE KS BORDER HAVE DROPPED INTO THE UPPER 30S AND LOWER 40S...BUT THE HRRR AND THE NAM12 SHOW THE DRY LINE WITH LOWER 50 DEW POINTS BACKING WESTWARD INTO THE SOUTHEAST CORNER OF CO THIS EVENING...WITH CAPE VALUES INCREASING TO AROUND 800 J/KG. 0-6 KM BULK SHEAR VALUES ARE EXPECTED TO BE AROUND 35 KTS. SO WL KEEP IN ISOLD TO SCT POPS OVR THE FAR SOUTHEAST PLAINS. THE HRRR ALSO KEEP SOME PCPN CHANCES IN THAT AREA UNTIL AT LEAST 06Z. THERE IS ALSO THE CHANCE THAT WE COULD SEE A SEVERE STORM OUT THERE WITH HAIL UP TO 1 INCH IN DIAMETER AND GUSTS NR 60 MPH. ONE MINOR CONCERN FOR TONIGHT IS THAT IF THE WINDS DECOUPLE IN THE SAN LUIS VALLEY TONIGHT...THE TEMPS COULD DROP TO AROUND FREEZING. ON SUNDAY THE UPR TROF WL BE MOVING ACRS CO...WITH GUSTY WESTERLY WINDS IN MOST AREAS...ALTHOUGH NOT AS STRONG AS TODAY. IT AGAIN LOOKS LIKE WIND AND HUMIDITY VALUES WILL REACH RED FLAG CRITERIA OVER TELLER AND FREMONT COUNTIES AND THE RAMPART RANGE...ALONG WITH THE CONTINUED DRY FUELS...THUS WL UPGRADE THE FIRE WEATHER WATCH TO A RED FLAG WARNING. WITH THAT TROF BRINGING COOLER AIR OVR THE AREA ON SUN...HIGH TEMPS WILL BE MUCH COOLER. THAT SYSTEM WILL ALSO PROBABLY BRING SOME ISOLD SHOWERS OR THUNDERSTORMS TO THE CENTRAL CO MTS SO WL LEAVE THAT IN THE FORECAST. .LONG TERM... (SUNDAY NIGHT THROUGH SATURDAY) SUNDAY NIGHT THROUGH TUESDAY...THE CLOSED UPPER LOW PRES SYSTEM PASSES ACROSS MT AND THE NORTHERN ROCKIES...BRUSHING THE STATE TO THE NORTH AND PRODUCING WESTERLY FLOW ALOFT ACROSS COLORADO. A TIGHT PRES GRADIENT SHOULD PRODUCE SOME BRISK WINDS ACROSS THE CWA SUNDAY NIGHT AND MONDAY...BUT THEN RELAXES FOR TUE. A WEAK COLD FRONT OR NORTHERLY SURGE IS FORECAST TO DROP DOWN THE E PLAINS MON MORNING...BUT AT THIS TIME LOOKS TO BE DRY AND A NON-PLAYER IN THE EXPECTED TEMPS...SO LOOK FOR DRY CONDITIONS AND MAX TEMPS IN THE LOWER 80S FOR THE PLAINS...AND IN THE 70S FOR THE HIGH VALLEYS. TUESDAY NIGHT THROUGH SATURDAY...THE UPPER FLOW BECOMES NORTHWESTERLY ACROSS THE GREAT BASIN AND ROCKY MT REGION FOR THE REST OF THE WORK WEEK...AS THE NORTHERN SYSTEM DROPS DOWN INTO THE MID-SECTION OF THE US...AND ANOTHER RIDGE OF HI PRES DEVELOPS OVER THE DESERT US. LLVL UPSLOPE FLOW THROUGH AT LEAST FRI IS EXPECTED TO KEP AN ISOLATED THREAT OF SOME CONVECTION OVER THE HIGHER TERRAIN AND E PLAINS THROUGH THE WEEK...WITH NEAR NORMAL TEMPS. MOORE && .AVIATION... STRONG SOUTH TO SOUTHWEST WINDS WILL CONTINUE INTO THE EVENING WITH 25 TO 35 KTS GENERALLY AT THE TAF SITES...AND GUSTS OF 35 TO 45 KTS. THESE SHOULD DECREASE THRU THE EVENING. VFR CONDITIONS WILL BE FOUND AT KCOS AND KPUB TONIGHT AND SUNDAY...BUT KALS WL HAVE REDUCED VSBY THIS EVENING DUE TO BLOWING DUST. ONCE THE WINDS DECREASE THE BLOWING DUST WL STOP...PROBABLY BY 02-03Z AND CONDITIONS WILL BE VFR THE REST OF THE NIGHT AND SUNDAY. WIND WILL BE A BIT BREEZY ON SUNDAY FROM THE WEST OR SOUTHWEST...WITH GENERALLY 20-30 KTS AND SOME HIGHER GUSTS. && .PUB WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 8 PM MDT THIS EVENING FOR COZ058-060- 065>071-073>076-080-082-084>089-093>099. RED FLAG WARNING UNTIL 10 PM MDT THIS EVENING FOR COZ221-222. RED FLAG WARNING FROM NOON TO 8 PM MDT SUNDAY FOR COZ221-222. && $$ 28/27
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
334 PM MDT SAT MAY 26 2012 .SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT) ISSUED AT 331 PM MDT SAT MAY 26 2012 TONIGHT...STRONG WINDS SHOULD CONTINUE THROUGH MOST OF THE EVENING. SATELLITE...ANALYSIS AND THE RUC SHOW THE FRONT THROUGH CENTRAL UT AND APPROACHING KSLC. THE FRONT IS SOMEWHAT PARALLEL TO THE FLOW ALOFT AND WILL MOVE SLOWLY EAST THE REST OF THIS AFTERNOON. PROJECTED FRONTAL PASSAGE AT THE MOAB AT 430 PM...GRAND JUNCTION AT ABOUT 600 PM...RIFLE AT ABOUT 700 PM AND ASPEN/VAIL ABOUT 800 PM. WINDS SHOULD SHIFT FROM SOUTH TO SOUTHWEST WITH FROPA AND BEGIN DECREASING ABOUT AN HOUR AFTER FROPA. THE RED FLAG WARNING AND HIGH WIND WARNING WILL CONTINUE PROBABLY UNTIL EXPIRATION TIME. VERY LITTLE PRECIP IS BEING PRODUCED BY THIS SYSTEM IN CO OR UT...ONLY CLOSE TO THE LOW CENTER OVER EXTREME NORTHERN UT. HAVE DECREASE THE CHANCE OF RAIN AS A RESULT. OVERNIGHT WINDS WILL RELAX...THOUGH THE GRADIENT FLOW SHOULD OVERPOWER THE NORMAL DIURNAL WINDS. SUNDAY THROUGH MONDAY...THE FLOW WILL CONTINUE VEERING TO BECOME WEST-SOUTHWEST. ON SUNDAY THE MAIN LOW WILL PASS FAR NORTH OF THE AREA WITH A SECONDARY TROUGH ROUNDING THE BOTTOM OF THE TROUGH AND BRINGING A CHANCE OF PRECIP TO THE NORTHERN QUARTER OF THE AREA FROM LATE MORNING THROUGH EARLY EVENING. MUCH DRIER AIR UP NORTH WILL ADVECT LATE SUNDAY NIGHT AFTER THIS TROUGH PASSES. ON MONDAY... ANOTHER VERY WEAK SHORTWAVE IN WESTERLY FLOW WILL BRUSH THE FAR NORTH ON MONDAY BUT CARRY LITTLE MOISTURE WITH IT FOR MAINLY JUST SOME INCREASE IN CLOUDS NORTH OF I-70. IT WILL ALSO KEEP SOME BREEZY CONDITIONS PRESENT MONDAY AFTERNOON. SUNSHINE WILL PREVAIL ACROSS THE CENTRAL AND SOUTH WITH TEMPS STARTING A WARMING TREND. .LONG TERM...(TUESDAY THROUGH SATURDAY) ISSUED AT 331 PM MDT SAT MAY 26 2012 TUESDAY...ANOTHER MOSTLY DRY SHORTWAVE DISTURBANCE ALOFT CRUISES ACROSS THE NORTH ON TUESDAY. LITTLE OR NO PRECIPITATION IS EXPECTED...BUT IT SHOULD BRING SOME AFTERNOON GUSTINESS ONCE AGAIN. TEMPS WILL CONTINUE TO WARM. TUE NIGHT THROUGH SATURDAY...DURING THESE PERIODS...TODAY`S GFS IS FOLLOWING THE ECMWF WITH TUE NIGHT`S WEAK SHORTWAVE STAYING FARTHER TO THE NORTH. JUST A REFLECTION OF THIS WAVE IS PROGGED TO BRUSH OUR NORTHEAST CORNER THROUGH EARLY WED. THE FLOW WILL BECOME MORE NORTHWEST BEHIND THIS DISTURBANCE...AND AS HIGH PRESSURE BUILDS OVER CA/NV BY THU. THE 12Z GFS IS VERY SIMILAR TO YESTERDAY`S 12Z EC AS IT DEVELOPS A LOW OFF NORTHERN BAJA UNDERNEATH THE HIGH PRESSURE RIDGE. HOWEVER TODAY`S 12Z EC PUTS THIS LOW FARTHER TO THE EAST. THE CANADIAN ALSO SHOWS A SIMILAR PATTERN...BUT HAS THE MOST WESTERLY SOLUTION. THE OTHER DIFFERENCE FROM YESTERDAY...IS THAT THE WESTERN HIGH PRESSURE RIDGE IS JUST NOT AS AMPLIFIED IN TODAY`S RUNS. MODELS PRETTY MUCH AGREE THAT WE WILL SEE NORTHWEST FLOW OVER THE CENTRAL ROCKIES THROUGH THU NIGHT AND PROBABLY INTO FRI. THEN THE FLATTENED RIDGE WILL PASS OVERHEAD THROUGH SAT. MODELS INDICATE THAT LIMITED MOISTURE WILL MOVE OVER THE RIDGE WHICH MAY BE ENOUGH FOR ISOLATED TERRAIN AND DIURNALLY BASED THUNDERSTORMS FRI AND SAT AFTERNOONS...FAVORING THE NORTH. TEMPERATURES WILL BE A COUPLE DEGREES WARMER THAN NORMAL READINGS ON WEDNESDAY...THEN SLOWLY WARM A FEW MORE DEGREES THROUGH THE END OF THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY AFTERNOON) ISSUED AT 331 PM MDT SAT MAY 26 2012 STRONG SURFACE WINDS WILL CONTINUE THROUGH THIS EVENING...WITH GUSTS POSSIBLY REACHING 60 MPH IN SOME VALLEYS...AND OVER 75 MPH AT EXPOSED MOUNTAIN LOCATIONS. THEREFORE MECHANICAL TURBULENCE WILL CONTINUE...ESPECIALLY NORTH OF AND ALONG RIDGES AND PEAKS. VFR CONDITIONS ARE GENERALLY EXPECTED...ALTHOUGH HAZE FROM BLOWING DUST AND SAND WILL LOWER VISIBILITIES AT TIMES INTO THE MVFR CATEGORY FOR SOME AREAS. WINDS WILL DIMINISH LATE THIS EVENING AND OVERNIGHT. && .FIRE WEATHER... ISSUED AT 331 PM MDT SAT MAY 26 2012 A RED FLAG WARNING REMAINS IN EFFECT THIS EVENING FOR ALL OF WESTERN COLORADO EXCEPT FIRE ZONE 291 /NORTHERN SAN JUAN MTNS/. HUMIDITY RECOVERY WILL BE BETTER TONIGHT DUE TO COOLER TEMPERATURES...THOUGH STILL ONLY MODERATE IN MANY PLACES DUE TO THE DRYNESS OF THE AIR BEHIND THE COLD FRONT. GUSTY WINDS WILL DEVELOP DURING THE AFTERNOONS SUNDAY THROUGH TUESDAY MAINLY ACROSS THE NORTH...BUT WIND SPEEDS WILL BE NO WHERE NEAR THE WIND OF TODAY. ANY ADDITIONAL FIRE WEATHER HIGHLIGHTS EARLY NEXT WEEK APPEAR UNLIKELY AT THIS TIME. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...HIGH WIND WARNING UNTIL 10 PM MDT THIS EVENING FOR COZ001>014- 017>023. RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200>203-207- 290-292-293. UT...HIGH WIND WARNING UNTIL 10 PM MDT THIS EVENING FOR UTZ022>025- 027>029. && $$ SHORT TERM......CC LONG TERM...... JAD/ELH AVIATION........EH FIRE WEATHER... JAD
AREA FORECAST DISCUSSION
NWS MIAMI FL
245 PM EDT SAT MAY 26 2012 .DISCUSSION...A BROAD UPPER LEVEL TROUGH CURRENTLY EXTENDS FROM THE EASTERN GULF AND ACROSS MUCH OF THE FLORIDA PENINSULA. HOWEVER, ITS OVERALL ORIENTATION IS RESULTING IN A BIT OF LINGERING SUBSIDENCE OVER THE REGION ALONG WITH SOME DRIER AIR IN THE MID AND LOW LEVELS. DESPITE THESE FACTORS, WE WILL CONTINUE TO EXPERIENCE ISOLATED TO SCATTERED SHOWERS AND STORMS THIS AFTERNOON, ESPECIALLY OVER THE INTERIOR AND WEST. IT APPEARS THE EAST COAST SEA BREEZE SHOULD WORK TO KEEP THE IMMEDIATE EAST COAST MAINLY DRY WITH THE STEERING FLOW TAKING ANY STORMS TO THE SOUTH- SOUTHWEST. H5 TEMPS REMAIN AROUND -10C AND WITH A DRY LAYER ALOFT, STRONG WIND GUSTS MAY OCCUR IN A COUPLE THUNDERSTORMS ALONG WITH SOME SMALL HAIL. 20-30 POPS ARE SUFFICIENT FOR MOST AREAS. THIS CONTINUES TO BE IN GOOD AGREEMENT WITH THE LATEST GUIDANCE, INCLUDING THE HRRR AND LOCAL WRF, WHICH SHOW THE BEST CHANCE OF CONVECTION OVER SOUTHERN AND WESTERN PORTIONS OF THE AREA THROUGH EARLY EVENING. ANY SHOWERS OR STORMS WILL GRADUALLY COME TO AN END AFTER 00Z, BUT COULD LINGER IN A FEW AREAS UNTIL ABOUT 02Z. A FEW SHOWERS OR EVEN ISOLATED THUNDERSTORMS COULD THEN RE-DEVELOP LATE TONIGHT, BUT MAINLY OVER THE GULF AND ATLANTIC WATERS, PARTICULARLY OFF THE PALM BEACH COAST. OTHERWISE, AS SURFACE WINDS BECOME LIGHT AND PERHAPS SHIFT TO THE SOUTHWEST, SOME PATCHY FOG COULD FORM ACROSS THE INTERIOR AFTER 06Z. SUBTROPICAL STORM BERYL WILL MOVE SOUTHWEST OFF THE CAROLINA COAST AND TOWARD THE NORTHEAST FLORIDA COAST BY SUNDAY EVENING. THIS WILL RESULT IN A GRADUAL INCREASE IN TOTAL ATMOSPHERIC MOISTURE ACROSS THE LOCAL AREA. MEANWHILE, H85 WINDS WILL BECOME SOUTHWESTERLY BY MIDDAY SUNDAY. THIS WILL HELP FOCUS CONVECTION OVER THE INTERIOR AND NORTHEAST PORTIONS OF THE REGION SUNDAY AFTERNOON AND EVENING. BERYL (OR ITS REMNANTS) WILL LIKELY CONTINUE PUSHING WEST ACROSS NORTH FLORIDA SUNDAY NIGHT, BEFORE ULTIMATELY TAKING A TURN BACK TO THE NORTHEAST SOMETIME MONDAY. CONTINUED SOUTH TO SOUTHWEST FLOW IN THE LOW LEVELS WILL BRING SCATTERED TO PERHAPS EVEN NUMEROUS SHOWERS AND STORMS ACROSS MUCH OF SOUTH FLORIDA ON MONDAY, WITH THE MOST CONCENTRATED ACTIVITY FOCUSED OVER THE NORTH AND EAST. WEST SOUTHWEST FLOW ALOFT COMBINED WITH CONSIDERABLE MOISTURE WILL RESULT IN MORE UNSETTLED WEATHER THROUGH AT LEAST THE MID WEEK PERIOD, ESPECIALLY AS AN UPPER LEVEL TROUGH LINGERS ACROSS THE AREA. ANOTHER SHORTWAVE WILL MOVE INTO THE LOWER MISSISSIPPI VALLEY BY THURSDAY AND FRIDAY. MEANWHILE, AN ASSOCIATED SURFACE LOW WILL ADVANCE INTO THE OHIO VALLEY. IF THIS VERIFIES, A COLD FRONT MAY PUSH THROUGH THE FLORIDA PENINSULA FRIDAY INTO EARLY NEXT SATURDAY WITH MORE SHOWERS AND THUNDERSTORMS IN ADVANCE OF IT. && .AVIATION...18Z ISSUANCE...EAST COAST SEA BREEZE MOVING ONSHORE EARLY THIS AFTERNOON AND GULF COAST SEA BREEZE ABOUT TO BEGIN MOVING ONSHORE AS WELL. NORTHERLY WIND FLOW ON FAR OUTER EDGE OF SUBTROPICAL STORM BERYL WILL FOCUS AFTERNOON/EARLY EVENING CONVECTION OVER INTERIOR SECTIONS OF THE PENINSULA. EXPECTED MOVEMENT OF ANY CONVECTION TO THE SSW-SW MEANS THAT SOME TSTMS COULD GET CLOSE ENOUGH TO FLL-MIA AREA TERMINALS TO WARRANT A VCTS MENTION THROUGH 03Z, BUT FEEL THAT TSTMS SHOULD NOT DIRECTLY AFFECT THESE SITES. SAME APPLIES FOR KAPF ALTHOUGH GULF COAST HAS A BETTER CHANCE OF TSTMS THAN THE EAST COAST. LIGHT WINDS TONIGHT WITH PERHAPS LOW CLOUDS/FOG INTERIOR TOWARDS DAYBREAK. WIND FLOW MORE FROM SW ON SUNDAY WHICH COULD FOCUS EARLY AFTERNOON TSTMS CLOSER TO E COAST. /MOLLEDA && .MARINE...SUBTROPICAL STORM BERYL WILL PUSH A NORTH-NORTHEAST SWELL INTO THE LOCAL ATLANTIC WATERS BY LATE TONIGHT, WHICH WILL CONTINUE TO IMPACT THE AREA THROUGH AT LEAST LATE SUNDAY NIGHT. IT STILL APPEARS THE SWELL WILL PEAK AROUND 3 FEET OFF THE PALM BEACH COAST, ESPECIALLY SUNDAY INTO SUNDAY EVENING. IT SHOULD BE NOTED THAT THE PREVAILING WIND DIRECTION AND SPEED ARE HIGHLY DEPENDENT ON THE ULTIMATE STRENGTH AND PATH OF BERYL. CONDITIONS ALONG THE EAST COAST WILL ALSO DETERIORATE WITH INCREASING SURF AND RIP CURRENTS. && .FIRE WEATHER...NO SIGNIFICANT CONCERNS AS RELATIVE HUMIDITIES WILL REMAIN ABOVE CRITICAL THRESHOLDS OVER AT LEAST THE NEXT SEVERAL DAYS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 73 87 73 87 / 20 50 40 50 FORT LAUDERDALE 75 88 74 87 / 20 50 40 40 MIAMI 74 89 73 88 / 20 40 30 40 NAPLES 74 89 74 88 / 20 30 30 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...14/MJB AVIATION/RADAR...59/RM
AREA FORECAST DISCUSSION
NWS MIAMI FL
1049 AM EDT SAT MAY 26 2012 .UPDATE...THE 12Z MFL SOUNDING INDICATED A PRECIPITABLE WATER OF 1.4 INCHES WITH DRIER AIR JUST NORTH AND WEST OF THE LOCAL AREA. OVERALL, THE AIR MASS HAS AT LEAST TEMPORARILY BECOME A BIT MORE STABLE, IN PART DUE TO SUBSIDENCE FROM SUBTROPICAL STORM BERYL. WHILE A FEW SHOWERS AND THUNDERSTORMS FORMED OVER THE ATLANTIC WATERS EARLY THIS MORNING, THAT ACTIVITY HAS DECREASED IN COVERAGE A BIT, WHICH IS TYPICAL IN THESE REGIMES. STILL, WE EXPECT AT LEAST A FEW SHOWERS AND STORMS TO FORM THIS AFTERNOON, ESPECIALLY OVER THE INTERIOR AND WEST. IT APPEARS THE EAST COAST SEA BREEZE SHOULD WORK TO KEEP THE IMMEDIATE EAST COAST MAINLY DRY. H5 TEMPS REMAIN AROUND -10C AND WITH A DRY LAYER ALOFT, STRONG WIND GUSTS MAY OCCUR IN A COUPLE THUNDERSTORMS ALONG WITH SOME SMALL HAIL. WE INCREASED POPS SLIGHTLY, TO 30 PERCENT, ACROSS PORTIONS OF THE INTERIOR AND OVER MUCH OF COLLIER, MAINLAND MONROE, AND PORTIONS OF HENDRY COUNTIES. THIS IS IN GOOD AGREEMENT WITH THE LATEST GUIDANCE, INCLUDING THE HRRR AND LOCAL WRF, WHICH PERFORMED QUITE WELL YESTERDAY. ANY CONVECTION WILL GRADUALLY COME TO AN END AFTER 00Z, BUT COULD LINGER IN A FEW AREAS UNTIL ABOUT 02Z. && .PREV DISCUSSION... /ISSUED 713 AM EDT SAT MAY 26 2012/ AVIATION...12Z ISSUANCE...NO SIGNIFICANT CHANGES FROM PREVIOUS DISCUSSION WITH MOSTLY VFR CONDITIONS WITH LIGHT 5 KTS OR LESS FLOW EXPECTED THROUGH THE MORNING HOURS. HOWEVER, DECIDED TO MENTION VCSH FOR EASTERN TERMINALS FROM KFLL NORTH DURING THE MORNING HOURS DUE TO RECENT DEVELOPMENT OF SHOWERS ACROSS THE ATLANTIC WATERS. MAIN FORECAST PROBLEM OF THE DAY IS WHETHER SHWRS/TSTMS WILL DEVELOP THIS AFTERNOON. GIVEN THE DEVELOPMENT AND PROXIMITY OF SUBTROPICAL STORM BERYL OVER THE WESTERN ATLANTIC...BELIEVE THAT SUBSIDENCE AROUND ITS PERIPHERY WL TEND TO INHIBIT (OR KEEP TO A MINIMUM) SHWRS/TSTMS ACTIVITY. EVEN, IF ANY STORM DEVELOPS, THE FORECAST STEERING FLOW SUGGEST A MOVEMENT MAINLY TOWARD EXTREME SOUTHERN PORTIONS OF SOUTH FLORIDA...THEREFORE DECIDED NOT TO MENTION ANY PRECIP IN THE TAFS FOR THIS AFTERNOON. WL ALSO EXPECT LOCAL WIND REGIME TO BE DOMINATED BY LOCAL SEA BREEZES WITH EASTERLY FLOW OVER THE ERN TERMINALS AND W-NW WINDS AT KAPF FROM MID-MORNING ON. PREV DISCUSSION... /ISSUED 502 AM EDT SAT MAY 26 2012/ .CORRECTION TO THE PREVIOUS DISCUSSION TO REPLACE TROPICAL STORM BERYL WITH SUBTROPICAL STORM BERYL... PREV DISCUSSION... /ISSUED 427 AM EDT SAT MAY 26 2012/ DISCUSSION... SUBTROPICAL STORM BERYL CONTINUES TO MOVE TO THE SOUTHEAST OFF THE SOUTH CAROLINA AND GEORGIA COAST. IT IS FORECAST TO CONTINUE ON A SOUTHEAST TRACK THROUGH SUNDAY AND APPROACH THE NORTHEAST FLORIDA COAST SUNDAY EVENING WITH CONSIDERABLE UNCERTAINTY IN THE FORECAST TRACK THEREAFTER. IN ADDITION TO SUBTROPICAL STORM BERYL THE OTHER MAJOR SYNOPTIC FEATURE ACROSS THE SOUTHEAST U.S. IS A LARGE UPPER LEVEL TROUGH EXTENDING ACROSS THE EASTERN GULF WITH MOST OF THE FLORIDA PENINSULA UNDER ITS INFLUENCE. BUT THE ORIENTATION OF THE UPPER LEVEL TROUGH IS SUCH THAT LARGE SCALE SUBSIDENCE IS TAKING PLACE ACROSS THE SOUTHEAST U.S. AND EASTERN GULF AND ACROSS FLORIDA. THAT WILL RESULT IN LITTLE CHANCE OF CONVECTION ACROSS THE SOUTH FLORIDA PENINSULA AND ADJACENT WATERS TODAY WITH JUST A SLIGHT CHANCE OF THUNDERSTORMS INDICATED IN THE FORECAST. BUT BY SUNDAY AFTERNOON IF SUBTROPICAL STORM BERYL APPROACHES THE NORTHEAST FLORIDA COAST AS FORECAST THEN LOW LEVEL MASS AND MOISTURE CONVERGENCE ACROSS THE REGION AROUND THE OUTER PERIPHERY OF BERYL COULD RESULT IN SCATTERED SHOWERS AND THUNDERSTORMS ACROSS SOUTH FLORIDA AND ADJACENT WATERS. BUT THERE IS SOME UNCERTAINTY IN THE FORECAST WITH THIS SCENARIO WITH THE NAM BEING MORE AGGRESSIVE WITH THE CHANCES OF CONVECTION AS OPPOSED TO THE GFS AND ECMWF MODELS. BUT IF SUBTROPICAL STORM BERYL MOVES A LITTLE FURTHER SOUTH THEN THIS SCENARIO COULD BE A BIT MORE REALISTIC. FOR THE REMAINDER OF THE FORECAST THROUGH THE WORK WEEK THE UNCERTAINTY OBVIOUSLY CONTINUES WITH THE REGIONAL WEATHER AFFECTED BY THE EVOLUTION OF THE REMAINS OF SUBTROPICAL STORM BERYL AS IT MOVES INLAND AND ON THE EVOLUTION OF THE UPPER LEVEL TROUGH DURING THIS PERIOD. BUT THE EXTENDED GUIDANCE INDICATES THAT SUFFICIENT MOISTURE COULD BE ACROSS THE REGION AND THE UPPER LEVEL TROUGH COULD STILL LINGER AS WELL WITH AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS POSSIBLE THROUGH AT LEAST MID WEEK. MARINE... THE LATEST GUIDANCE INDICATES GULF STREAM SEAS EAST OF PALM BEACH FORECAST TO BUILD TO NEAR 6 FEET BY SUNDAY AFTERNOON AND SLOWLY DECREASING EARLY MONDAY BUT NEED TO STRESS THE UNCERTAINTIES IN BOTH THE WIND AND SEAS FORECAST. MARINE BUOYS OFF THE COAST FROM CAPE CANAVERAL CURRENTLY INDICATE A SWELL NEAR 5 FEET WELL AHEAD OF SUBTROPICAL STORM BERYL BUT BY THE TIME IT MIGHT REACH THE ATLANTIC WATERS OFF PALM BEACH COUNTY ONLY A SMALL SWELL WOULD BE LEFT. THE LATEST MARINE GUIDANCE INDICATES THAT SUBTROPICAL STORM BERYL COULD GENERATE A LONG PERIOD SWELL THAT COULD IMPACT THE LOCAL ATLANTIC WATERS LATE IN THE WEEKEND. THE LOCAL NWPS MARINE FORECAST MODEL INDICATED A LONG PERIOD NORTHERLY SMALL SWELL ENTERING THE WATERS EAST OF PALM BEACH COUNTY EARLY SUNDAY THEN FORECAST TO BUILD TO A 2 TO 3 FOOT SWELL LATER ON SUNDAY AND THEN SLOWLY DIMINISHING EARLY MONDAY. OBVIOUSLY THIS SCENARIO WILL ULTIMATELY DEPEND ON THE TRACK OF SUBTROPICAL STORM BERYL. FIRE WEATHER... NO FIRE WEATHER CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 87 74 88 73 / 20 20 50 30 FORT LAUDERDALE 87 75 88 74 / 20 20 50 30 MIAMI 89 74 89 75 / 20 20 40 30 NAPLES 89 74 86 74 / 20 20 40 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...14/MJB AVIATION/RADAR...59/RM
AREA FORECAST DISCUSSION
NWS MIAMI FL
120 AM EDT SAT MAY 26 2012 .AVIATION...VFR CONDITIONS WITH LIGHT (<5 KTS) FLOW EXPECTED THROUGH THE MORNING HOURS. MAIN FORECAST PROBLEM OF THE DAY IS WHETHER SHWRS/TSTMS WILL DEVELOP SATURDAY AFTERNOON. GIVEN THE DEVELOPMENT AND PROXIMITY OF SUBTROPICAL STORM BERYL OVER THE WESTERN ATLANTIC...BELIEVE THAT SUBSIDENCE AROUND ITS PERIPHERY WL TEND TO INHIBIT (OR KEEP TO A MINIMUM) SHWRS/TSTMS ACTIVITY SATURDAY AFTERNOON. EVEN, IF ANY STORM DEVELOPS, THE FORECAST STEERING FLOW SUGGEST A MOVEMENT MAINLY TOWARD EXTREME SOUTHERN PORTIONS OF SOUTH FLORIDA...THEREFORE DECIDED NOT TO MENTION ANY PRECIP IN THE TAFS. WL ALSO EXPECT LOCAL WIND REGIME TO BE DOMINATED BY LOCAL SEA BREEZES WITH EASTERLY FLOW OVER THE ERN TERMINALS AND W-NW WINDS AT KAPF FROM MID-MORNING ON. && .PREV DISCUSSION... /ISSUED 815 PM EDT FRI MAY 25 2012/ ..NO SIGNIFICANT CHANGES. IN THE MARINE ZONES...LITTLE IF ANY CHANGES. PREVIOUS DISCUSSION...AN AREA OF LOW PRESSURE NORTH OF THE BAHAMAS WILL MOVE NORTHEAST AND INTENSIFY THROUGH THIS EVENING, POSSIBLY STRENGTHENING INTO A SUBTROPICAL OR TROPICAL ENTITY BY LATE TONIGHT. A LARGE AMPLITUDE UPPER LEVEL TROUGH ALSO REMAINS ACROSS THE SOUTHEAST U.S. AND EASTERN GULF WITH THE AXIS EXTENDING JUST WEST OF SOUTH FLORIDA AND INTO THE VICINITY OF THE YUCATAN PENINSULA. MEANWHILE, WEAK SURFACE HIGH PRESSURE IS ATTEMPTING TO PUSH SOUTH OVER THE FLORIDA PENINSULA. WHILE THIS FEATURE HAS AIDED IN LOWER PRECIPITABLE WATERS, SUFFICIENT AMOUNTS OF MOISTURE WILL REMAIN IN PLACE ACROSS THE INTERIOR AND WEST THROUGH THIS EVENING FOR AT LEAST ISOLATED TO SCATTERED CONVECTION. ALONG MUCH OF THE EAST COAST, POPS HAVE BEEN REDUCED TO 10-20 PERCENT FOR THIS AFTERNOON AND EARLY EVENING. WITH A LACK OF APPRECIABLE FORCING ALOFT, ANY AFTERNOON/EVENING CONVECTION WILL BE DRIVEN MAINLY BY SEA BREEZE INTERACTIONS AND LOCAL MESO-SCALE EFFECTS. THE HRRR SHOWS THE WEST COAST SEA BREEZE PUSHING INLAND AND PROVIDING ENOUGH LIFT TO RESULT IN SCATTERED CONVECTION OVER WESTERN AND INTERIOR PORTIONS OF THE REGION BY 21Z. A FEW STORMS COULD BECOME STRONG OR EVEN MARGINALLY SEVERE, ESPECIALLY WITH ANY CELL MERGERS. STRONG WINDS ARE THE PRIMARY CONCERN, ALTHOUGH SOME HAIL COULD ALSO OCCUR. WITH THE EAST COAST SEA BREEZE CONTINUING TO ADVANCE INLAND, LITTLE ACTIVITY IS EXPECTED ALONG THE IMMEDIATE EAST COAST. ANY SHOWERS OR THUNDERSTORMS WILL GRADUALLY END AFTER 00Z, ALTHOUGH SOME LINGERING ISOLATED ACTIVITY IS POSSIBLE OVERNIGHT, MAINLY LIMITED TO THE GULF AND ATLANTIC WATERS. FORECAST SOUNDINGS SHOW A SLIGHT INCREASE IN PRECIPITABLE WATERS ON SATURDAY WHILE CONDITIONAL INSTABILITY COMBINED WITH SEA BREEZE BOUNDARIES WILL RESULT IN ANOTHER ROUND OF ISOLATED TO SCATTERED AFTERNOON CONVECTION. A FEW STORMS COULD AGAIN BE STRONG, ALTHOUGH OVERALL COVERAGE SHOULD BE SIMILAR TO TODAY. THE LATEST GUIDANCE REMAINS RATHER CONSISTENT AND SHOWS THE DEVELOPING WARM-CORE LOW COMING TO A POSITION OFF THE SOUTH CAROLINA COAST BY LATE SATURDAY. ITS FORWARD MOVEMENT WILL THEN SLOW AND ULTIMATELY GO BACK TO THE WEST OR SOUTHWEST IN RESPONSE TO BUILDING HIGH PRESSURE OFF THE MID ATLANTIC COAST. AS DEEP LAYER MOISTURE INCREASES AND H85 WINDS BECOME SOUTHWESTERLY ACROSS THE LOCAL AREA, CONVECTION MAY BECOME A BIT MORE WIDESPREAD AND INTENSE ON SUNDAY AFTERNOON AND EVENING. A SIMILAR PATTERN IS EXPECTED ON MONDAY. WESTERLY FLOW ALOFT COUPLED WITH SIGNIFICANT MOISTURE WILL PRODUCE AT LEAST SCATTERED SHOWERS AND STORMS TUESDAY INTO WEDNESDAY. THE POSSIBLE WARM-CORE LOW PRESSURE SYSTEM WILL HAVE WEAKENED, BUT WILL ONLY SLOWLY PUSH BACK TO THE EAST NORTHEAST ACROSS THE FLORIDA PANHANDLE AND WESTERN ATLANTIC. SO WHILE THE BEST SYNOPTIC FORCING WILL REMAIN TO THE NORTH, A RATHER UNSETTLED PATTERN WILL LIKELY PREVAIL WITH PRECIPITATION CHANCES GENERALLY AT OR ABOVE CLIMO. AVIATION...18Z ISSUANCE...MAINLY VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. THE EAST COAST SEA BREEZE HAS DEVELOPED AND CONTINUES TO MOVE INLAND. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS INTERIOR SECTIONS AND THEN THEY COULD DRIFT BACK CLOSER TO THE EAST COAST TERMINALS LATER THIS AFTERNOON. A WEST COAST SEA BREEZE WILL ALSO DEVELOP AT KAPF AS THE AFTERNOON PROGRESSES. ANY SHOWERS OR THUNDERSTORMS WILL DIMINISH LATER THIS EVENING AND WINDS WILL BECOME LIGHT AND VARIABLE ACROSS ALL SOUTH FLORIDA TERMINALS. MARINE...WINDS AND SEAS ARE FORECAST TO REMAIN BELOW ADVISORY LEVELS THROUGH AT LEAST SATURDAY. HOWEVER, A SMALL SWELL MAY BEGIN TO IMPACT THE LOCAL ATLANTIC WATERS, ESPECIALLY OFF THE PALM BEACH COAST, BY SUNDAY. THERE IS SOME UNCERTAINTY IN THE FORECAST AS THE ULTIMATE TRACK AND INTENSITY OF A POSSIBLE WARM CORE SYSTEM TO THE NORTH WILL HAVE AT LEAST SOME IMPACT ON LOCAL MARINE CONDITIONS. FIRE WEATHER...NO SIGNIFICANT CONCERNS AS RELATIVE HUMIDITIES AND OVERALL ATMOSPHERIC MOISTURE WILL REMAIN HIGH THROUGH THE WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 87 74 88 74 / 30 20 40 30 FORT LAUDERDALE 87 75 88 76 / 30 20 40 30 MIAMI 88 74 89 74 / 30 20 40 30 NAPLES 91 73 90 73 / 30 20 30 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...60/BD AVIATION/RADAR...47/RGH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
528 PM CDT SAT MAY 26 2012 .DISCUSSION... 338 PM CDT MAIN FORECAST CHALLENGES ARE WITH A WARMING TREND STILL ON TRACK AND MUCH WARMER CONDITIONS FOR THE ENTIRE CWA EXPECTED SUNDAY AND MONDAY...WITH THUNDERSTORM CHANCES LATE THIS AFTERNOON AND EARLY EVENING STILL POSSIBLE MAINLY FOR AREAS ACROSS FAR NORTHERN ILLINOIS. ONGOING CHANGES ACROSS THE CWA THIS AFTERNOON AS A MUCH WARMER AIRMASS CONTINUES TO MOVE NORTH ACROSS THE CENTRAL CONUS THIS AFTERNOON. AS HEIGHTS ALOFT SLOWLY RISE THIS AFTERNOON...SURFACE LOW OVER THE CENTRAL PLAINS CONTINUES TO DEVELOP WITH SURFACE WARM FRONT PUSHING NORTH THROUGH THE REGION. LATEST SURFACE ANALYSIS SHOWING WARM FRONT PUSHING NORTH THROUGH AREAS NEAR STERLING IN NORTHWEST ILLINOIS SOUTHEAST TO AREAS NEAR KANKAKEE. PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS THE ENTIRE CWA TODAY WITH TEMPERATURES REMAINING IN THE 70S AND LOW 80S NORTH OF THE FRONT...WITH TEMPERATURES QUICKLY RISING TO THE UPPER 80S TO LOW 90S SOUTH OF THE FRONT. THIS FRONT WILL CONTINUE LIFTING NORTH THIS EVENING WITH STEADY IF NOT WARMING TEMPS THROUGH THE OVERNIGHT HOURS AND EARLY MORNING TIME FRAME SUNDAY MORNING. THUS...PAVING THE WAY FOR A WARM NEXT COUPLE OF DAYS WITH CURRENT FORECAST HIGH TEMPERATURES STILL ON TRACK. STRONG WARM AIR ADVECTION CURRENTLY ONGOING ACROSS OVER THE ENTIRE REGION WILL CONTINUE WITH MAIN THERMAL AXIS SHIFTING OVERHEAD ON SUNDAY BRINGING 850MB TEMPS OF 20-22C ACROSS THE CWA. THIS COINCIDING WITH FULL SUNSHINE AND STRONG MIXING OF SOUTH/SOUTHWEST FLOW...WILL ALL AID IN TEMPERATURES RISING INTO THE MID AND UPPER 90S ON SUNDAY...WITH STRONG FLOW KEEPING ANY LAKE BREEZE AT BAY AND WARMER TEMPERATURES TO BE OBSERVED THROUGHOUT THE ENTIRE CWA. TEMPERATURES IN THE 90S EXPECTED ONCE AGAIN ON MONDAY BUT NOT QUITE AS HIGH DUE TO PRECIP/CLOUD COVER ISSUES WITH SURFACE WAVE AND FRONTAL BOUNDARY APPROACHING FROM THE WEST. AFTER A COMPLEX OF SHOWERS AND THUNDERSTORMS PUSHED EAST ACROSS AREAS IN NORTHERN ILLINOIS THIS MORNING...THE CWA HAS REMAINED MOSTLY DRY THIS AFTERNOON. DESPITE THIS DRY TREND THUS FAR...STILL FEEL THAT THERE IS A POSSIBILITY FOR AREAS ACROSS FAR NORTHERN ILLINOIS TO OBSERVE SOME SHOWERS AND THUNDERSTORMS...WITH STILL AN ISOLATED SEVERE THREAT REMAINING. ALL MODEL GUIDANCE TODAY AS BEEN USELESS WITH MOST GUIDANCE CONTINUING TO GENERATE CONVECTION WHERE THERE HAS BEEN NONE...AND MOSTLY LIKELY NOT BE. DESPITE A FRONTAL BOUNDARY/IMPETUS FOR CONVECTION LIFTING NORTH ACROSS THE REGION AND SURGE OF GOOD MOISTURE MAKING ITS WAY NORTH...WARMING ALOFT HAS LIMITED UPDRAFT DEVELOPMENT. LATEST RUC ANALYSIS INDICATING THAT 700MB TEMPS OF 10-12C ARE PUSHING OVERHEAD...WHICH IN THE ABSENCE OF BOTH GOOD SURFACE LIFT AND LARGE SCALE ASCENT...HAS LIMITED ANY THUNDERSTORM DEVELOPMENT TODAY. THIS HAS BEEN NOTED WITH THE SHOWERS WHICH HAVE BEEN TRYING TO GET GOING ACROSS IOWA...WHICH ARE ALREADY DISSIPATING. FEEL THAT THE ONLY CHANCE FOR THE CWA TO OBSERVE THUNDERSTORM DEVELOPMENT THIS AFTERNOON WILL BE ACROSS FAR NORTHERN ILLINOIS. HAVE BEEN MONITORING CONVECTION ACROSS SOUTHEAST MINNESOTA AND WESTERN ILLINOIS AND FEEL THAT THIS IS THE AREA WHICH MAY HELP STEER CONVECTION SOUTHWARD. AS A MID LEVEL IMPULSE CONTINUES TO PROGRESS TO THE EAST/NORTHEAST INTO SOUTHERN WISCONSIN...THIS COULD PROVIDE LARGE SCALE ASCENT WHICH COULD THEN INTERACT WITH A NORTHWARD SURGING WARM FRONT. SOME DEVELOPMENT ALONG THE SOUTHERN PORTION OF THIS COMPLEX HAS BEEN OBSERVED THIS AFTERNOON AND CONTINUES TO SEEM PROBABLE FOR THE REMAINDER OF THE AFTERNOON AND EARLY AFTERNOON WITH THE AFOREMENTIONED SYNOPTIC DETAILS COMING INTO BETTER LINE. MOISTURE ADVECTION NORTH COULD HELP FEED THIS DEVELOPMENT AND EVEN HELP STEER ANY CONVECTION FURTHER SOUTHEAST. IF THIS DEVELOPMENT WERE TO SHIFT SOUTH INTO THE NORTHERN PORTIONS OF THE CWA...AN OUTSIDE WIND AND HAIL THREAT COULD STILL BE POSSIBLE AS STEEP MID LEVEL LAPSE RATES REMAIN. RIGHT NOW...THIS IS THE LOW END SOLUTION BUT STILL A POSSIBILITY THAT NEEDS TO CONTINUE TO BE MONITORED. RODRIGUEZ && .CLIMATE... ...RECORD BREAKING HIGH TEMPERATURES EXPECTED SUNDAY MAY 27TH... 529 PM...CURRENTLY FORECASTING A RECORD HIGH AT ORD OF 96 ON SUNDAY...MAY 27TH. THE ORD RECORD HIGH FOR MAY 27TH IS 94 SET IN 1911. THE EARLIEST OCCURRENCE OF 96 DEGREES OR HIGHER IN CHICAGO IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 98 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 96 OR HIGHER ON SUNDAY MAY 27TH...IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. CURRENTLY FORECASTING A RECORD HIGH OF 95 AT RFD ON SUNDAY...MAY 27TH. THE RFD RECORD HIGH FOR MAY 27TH IS 92 SET IN 1978. A LIST OF RECORD HIGH TEMPS AND RECORD HIGH MINIMUM TEMPS FOR THE THE HOLIDAY WEEKEND IS BELOW. DEPENDING ON FRONTAL TIMING AND ASSOCIATED PRECIP/CLOUD COVER...REACHING RECORD HIGHS ON MONDAY IS STILL POSSIBLE...BUT CONFIDENCE IS LOWER THAN REACHING RECORD HIGHS ON SUNDAY. RECORDS FOR ORD... HIGH TEMP/YEAR HIGH MINIMUM TEMP/YEAR SUN MAY 27TH 94/1911 75/1911 MON MAY 28TH 93/1977 74/2006 RECORDS FOR RFD... SUN MAY 27TH 92/1978 71/1914 MON MAY 28TH 93/2006 69/2006 RODRIGUEZ && .FIRE WEATHER... 451 PM CDT AS A WARM FRONTAL BOUNDARY CONTINUES TO LIFT NORTH THIS EVENING...IT WILL HELP USHER A MUCH WARMER AIR MASS AND MORE MOIST ENVIRONMENT NORTH ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. DESPITE HIGHER MOISTURE AIR SHIFTING NORTH...COULD STILL OBSERVE SOME LOW RELATIVE HUMIDITY VALUES AROUND THE 35 PERCENT AREA SUNDAY AFTERNOON ALONG AND SOUTH OF INTERSTATE 80 AS STRONG MIXING AND HIGH DEWPOINT DEPRESSIONS WILL BE IN PLACE. ALTHOUGH...NOT EXPECTING THE WINDS TO BE TOO STRONG IN THESE LOCATIONS WITH 20FT WINDS EXPECTED TO TOP OFF AT 10-15MPH IN THE AFTERNOON. SIMILAR TEMP AND DEWPOINT CONDITIONS ARE EXPECTED ON MONDAY...ALTHOUGH NOT QUITE AS WARM. NONETHELESS...LOW RELATIVE HUMIDITY VALUES OF 30-35 PERCENT ARE STILL EXPECTED. STRONGER WINDS WILL ALSO BE IN PLACE MONDAY AFTERNOON AS LOW PRESSURE AND A COLD FRONTAL BOUNDARY APPROACH FROM THE WEST...WITH 20FT WINDS EXPECTED TO BE CLOSER TO 20MPH. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * NE WINDS EXPECTED TO CONTINUE THROUGH MID EVENING. GUSTS AROUND 20 KT POSSIBLE TIL 00Z OR SO. * LOW CHANCE FOR ISOLD/SCT SHRA/TSRA NEAR THE TERMINALS EARLY THIS EVENING. * SOUTH WINDS TO START SUNDAY BECOMING GUSTY 20-25 KT SUNDAY AFTERNOON. MDB //DISCUSSION...UPDATED 22Z... WINDS HAVE SHIFTED NORTHEAST ACROSS THE TERMINALS THANKS TO THE PASSAGE OF A BOUNDARY THAT MAY BE A SECOND LAKE BREEZE BOUNDARY. EXPECT THAT THESE NORTHEAST WINDS WILL CONTINUE THROUGH EARLY OR MID EVENING BEFORE TURNING SOUTHEASTERLY MID OR LATE EVENING. THIS WILL BE DEPENDENT ON THE WARM FRONT THAT IS SOUTH OF THE TERMINALS AND IT APPEARS ITS NORTHWARD MOVEMENT WILL BE STALLED BY THE COOLING THAT HAS DEVELOPED OFF THE LAKE. A PORTION OF THE FRONT MAY LIFT NORTHWARD WHILE SECTIONS CLOSER TO LAKE MICHIGAN REMAINS HUNG UP SO RFD COULD SEE A SHIFT TO SOUTHERLY WINDS FIRST. WILL CONTINUE MONITOR TIMING OF WIND TRENDS INTO THE EVENING. SHRA/TSRA STILL POSSIBLE BUT CHANCE CONTINUES TO LOOK LOW. MOST FAVORED AREA WOULD BE FROM RFD TO PWK AND POINTS NORTH INTO MID EVENING. MDB FROM 18Z... WARM FRONTAL BOUNDARY CONTINUES TO SLOWLY LIFT NORTH ACROSS SOUTHEAST IOWA STRETCHING EAST THROUGH CENTRAL IL/IN. WINDS NORTH OF THIS BOUNDARY AND ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS CONTINUES TO BE EASTERLY WITH OCCASIONAL GUSTS INTO THE MID/UPR TEENS. SOUTH OF THE BOUNDARY WINDS VEER SOUTHEAST/SOUTH. VISIBLE IMAGERY WAS INDICATING A NARROW CHANNEL OF A CUMULUS FIELDS...HOWEVER IT APPEARS TO REMAIN RATHER FLAT. SOME BETTER GROWTH IN THE CLOUDS EXISTS ACROSS SOUTHEAST MN/WESTERN WI/FAR NORTHERN IA. THIS AREA OF CONVECTION HAS POSED SOME CONCERN FOR NORTHERN IL AIRFIELDS LATER THIS AFTN/EVE...HOWEVER THE GENERAL THINKING IS THAT THIS WILL SLIDE EAST AND AVOID MOST OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...IF NOT ALL OF THEM. AT THIS TIME HAVE GONE WITH A DRY FORECAST...WITH JUST A FEW/SCT CLOUDS ARND 5KFT AGL. BASED ON MODEL SOUNDINGS A THIN MOISTURE LAYER WAS NOTED AT 5KFT AGL...AND THEN DRIES AS THE WARM AIR ADVECTS OVER THE REGION. THIS SHOULD AID IN LIMITING THE CHANCES FOR SHOWERS AND THUNDERSTORMS LATER. THEN AS THE BOUNDARY LIFTS NORTH INTO SOUTHERN WISC...WINDS WILL REMAIN SOUTHERLY THROUGH THE REMAINDER OF THE OVERNIGHT AND SUNDAY PERIOD. WINDS WILL BECOME BETTER MIXED DURING THE DAY SUN..AND CAN EASILY SEE WINDS GUSTING TO 20-25KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 22Z... * HIGH CONFIDENCE IN NE WINDS CONTINUING THROUGH 00Z...MEDIUM-HIGH CONFIDENCE THROUGH MID EVENING. * HIGH CONFIDENCE THAT THREAT FOR SHRA/TSRA IS LOW THIS EVENING. * HIGH CONFIDENCE IN WX TRENDS OVERNIGHT AND SUNDAY. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...SOUTHWEST WINDS POSSIBLY GUSTING OVER 30KT. CHANCE OF TSRA AT NIGHT...OTHERWISE VFR TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SHRA. FRIDAY...VFR. IZZI && .MARINE... 247 PM CDT A LARGE AREA OF HIGH PRESSURE WILL REMAIN OVER ONTARIO AND WESTERN QUEBEC TONIGHT. LOW PRESSURE MOVES EAST ACROSS THE CENTRAL ROCKIES AND THEN NORTHEAST TO SOUTH DAKOTA OVERNIGHT... LIFTING A WARM FRONT NORTH OVER THE SOUTHERN PORTION OF LAKE MICHIGAN. THE HIGH WILL DRIFT NORTH AND BE CENTERED OVER SOUTHERN HUDSON BAY BY SUNDAY EVENING WHILE THE LOW MOVES VERY SLOWLY NORTH-NORTHEAST TO EASTERN NORTH DAKOTA AND THE WARM FRONT CONTINUING TO MOVE NORTH ACROSS NORTHERN LAKE MICHIGAN. SOUTHEAST TO SOUTH WINDS WILL STRENGTHEN A BIT DUE TO THE INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND LOW PRESSURE AREAS BUT DUE TO THE STABILIZING EFFECT OF THE COOL WATER UNDER VERY WARM AIR...PREVAILING SPEEDS ARE NOT EXPECTED TO 15-20KT. THE LOW MOVES TRACKS EASTWARD JUST NORTH OF THE NORTHERN GREAT LAKES REGION SUNDAY NIGHT THROUGH MONDAY NIGHT SWEEPING A COLD FRONT THROUGH THE WESTERN AND CENTRAL GREAT LAKES LATER MONDAY AND MONDAY NIGHT SHIFTING WINDS TO OUT OF THE WEST AND NORTHWEST FOR TUESDAY. AS THE LOW CONTINUES EAST TO QUEBEC ON TUESDAY A RIDGE OF HIGH PRESSURE BUILDS SOUTH FROM CENTRAL CANADA ACROSS THE NORTHERN AND CENTRAL PLAINS. AS THE RIDGE EVENTUALLY DRIFTS EASTWARD WEDNESDAY AND OVER THE UPPER MIDWEST AND WESTERN GREAT LAKES THURSDAY WINDS DROP OFF TO 10 KT OR LESS AS THE CENTER OF THE HIGH APPROACHES. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
511 PM CDT SAT MAY 26 2012 .DISCUSSION... 338 PM CDT MAIN FORECAST CHALLENGES ARE WITH A WARMING TREND STILL ON TRACK AND MUCH WARMER CONDITIONS FOR THE ENTIRE CWA EXPECTED SUNDAY AND MONDAY...WITH THUNDERSTORM CHANCES LATE THIS AFTERNOON AND EARLY EVENING STILL POSSIBLE MAINLY FOR AREAS ACROSS FAR NORTHERN ILLINOIS. ONGOING CHANGES ACROSS THE CWA THIS AFTERNOON AS A MUCH WARMER AIRMASS CONTINUES TO MOVE NORTH ACROSS THE CENTRAL CONUS THIS AFTERNOON. AS HEIGHTS ALOFT SLOWLY RISE THIS AFTERNOON...SURFACE LOW OVER THE CENTRAL PLAINS CONTINUES TO DEVELOP WITH SURFACE WARM FRONT PUSHING NORTH THROUGH THE REGION. LATEST SURFACE ANALYSIS SHOWING WARM FRONT PUSHING NORTH THROUGH AREAS NEAR STERLING IN NORTHWEST ILLINOIS SOUTHEAST TO AREAS NEAR KANKAKEE. PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS THE ENTIRE CWA TODAY WITH TEMPERATURES REMAINING IN THE 70S AND LOW 80S NORTH OF THE FRONT...WITH TEMPERATURES QUICKLY RISING TO THE UPPER 80S TO LOW 90S SOUTH OF THE FRONT. THIS FRONT WILL CONTINUE LIFTING NORTH THIS EVENING WITH STEADY IF NOT WARMING TEMPS THROUGH THE OVERNIGHT HOURS AND EARLY MORNING TIME FRAME SUNDAY MORNING. THUS...PAVING THE WAY FOR A WARM NEXT COUPLE OF DAYS WITH CURRENT FORECAST HIGH TEMPERATURES STILL ON TRACK. STRONG WARM AIR ADVECTION CURRENTLY ONGOING ACROSS OVER THE ENTIRE REGION WILL CONTINUE WITH MAIN THERMAL AXIS SHIFTING OVERHEAD ON SUNDAY BRINGING 850MB TEMPS OF 20-22C ACROSS THE CWA. THIS COINCIDING WITH FULL SUNSHINE AND STRONG MIXING OF SOUTH/SOUTHWEST FLOW...WILL ALL AID IN TEMPERATURES RISING INTO THE MID AND UPPER 90S ON SUNDAY...WITH STRONG FLOW KEEPING ANY LAKE BREEZE AT BAY AND WARMER TEMPERATURES TO BE OBSERVED THROUGHOUT THE ENTIRE CWA. TEMPERATURES IN THE 90S EXPECTED ONCE AGAIN ON MONDAY BUT NOT QUITE AS HIGH DUE TO PRECIP/CLOUD COVER ISSUES WITH SURFACE WAVE AND FRONTAL BOUNDARY APPROACHING FROM THE WEST. AFTER A COMPLEX OF SHOWERS AND THUNDERSTORMS PUSHED EAST ACROSS AREAS IN NORTHERN ILLINOIS THIS MORNING...THE CWA HAS REMAINED MOSTLY DRY THIS AFTERNOON. DESPITE THIS DRY TREND THUS FAR...STILL FEEL THAT THERE IS A POSSIBILITY FOR AREAS ACROSS FAR NORTHERN ILLINOIS TO OBSERVE SOME SHOWERS AND THUNDERSTORMS...WITH STILL AN ISOLATED SEVERE THREAT REMAINING. ALL MODEL GUIDANCE TODAY AS BEEN USELESS WITH MOST GUIDANCE CONTINUING TO GENERATE CONVECTION WHERE THERE HAS BEEN NONE...AND MOSTLY LIKELY NOT BE. DESPITE A FRONTAL BOUNDARY/IMPETUS FOR CONVECTION LIFTING NORTH ACROSS THE REGION AND SURGE OF GOOD MOISTURE MAKING ITS WAY NORTH...WARMING ALOFT HAS LIMITED UPDRAFT DEVELOPMENT. LATEST RUC ANALYSIS INDICATING THAT 700MB TEMPS OF 10-12C ARE PUSHING OVERHEAD...WHICH IN THE ABSENCE OF BOTH GOOD SURFACE LIFT AND LARGE SCALE ASCENT...HAS LIMITED ANY THUNDERSTORM DEVELOPMENT TODAY. THIS HAS BEEN NOTED WITH THE SHOWERS WHICH HAVE BEEN TRYING TO GET GOING ACROSS IOWA...WHICH ARE ALREADY DISSIPATING. FEEL THAT THE ONLY CHANCE FOR THE CWA TO OBSERVE THUNDERSTORM DEVELOPMENT THIS AFTERNOON WILL BE ACROSS FAR NORTHERN ILLINOIS. HAVE BEEN MONITORING CONVECTION ACROSS SOUTHEAST MINNESOTA AND WESTERN ILLINOIS AND FEEL THAT THIS IS THE AREA WHICH MAY HELP STEER CONVECTION SOUTHWARD. AS A MID LEVEL IMPULSE CONTINUES TO PROGRESS TO THE EAST/NORTHEAST INTO SOUTHERN WISCONSIN...THIS COULD PROVIDE LARGE SCALE ASCENT WHICH COULD THEN INTERACT WITH A NORTHWARD SURGING WARM FRONT. SOME DEVELOPMENT ALONG THE SOUTHERN PORTION OF THIS COMPLEX HAS BEEN OBSERVED THIS AFTERNOON AND CONTINUES TO SEEM PROBABLE FOR THE REMAINDER OF THE AFTERNOON AND EARLY AFTERNOON WITH THE AFOREMENTIONED SYNOPTIC DETAILS COMING INTO BETTER LINE. MOISTURE ADVECTION NORTH COULD HELP FEED THIS DEVELOPMENT AND EVEN HELP STEER ANY CONVECTION FURTHER SOUTHEAST. IF THIS DEVELOPMENT WERE TO SHIFT SOUTH INTO THE NORTHERN PORTIONS OF THE CWA...AN OUTSIDE WIND AND HAIL THREAT COULD STILL BE POSSIBLE AS STEEP MID LEVEL LAPSE RATES REMAIN. RIGHT NOW...THIS IS THE LOW END SOLUTION BUT STILL A POSSIBILITY THAT NEEDS TO CONTINUE TO BE MONITORED. RODRIGUEZ && .CLIMATE... ...RECORD BREAKING HIGH TEMPERATURES EXPECTED SUNDAY MAY 27TH... 302 PM...CURRENTLY FORECASTING A NEW RECORD HIGH AT ORD OF 96 ON SUNDAY...MAY 27TH. THE ORD RECORD HIGH FOR MAY 27TH IS 94 SET IN 1911. THE EARLIEST OCCURRENCE OF 96 DEGREES OR HIGHER IN CHICAGO IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 98 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 96...OR HIGHER...ON SUNDAY MAY 27TH...IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. CURRENTLY FORECASTING A NEW RECORD HIGH OF 98 AT RFD ON SUNDAY... MAY 27TH. THE RFD RECORD HIGH FOR MAY 27TH IS 92 SET IN 1978. THE EARLIEST OCCURRENCE OF 98 DEGREES OR HIGHER IN ROCKFORD IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 106 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 98...OR HIGHER...ON SUNDAY MAY 27TH... IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. A LIST OF RECORD HIGH TEMPS AND RECORD HIGH MINIMUM TEMPS FOR THE UPCOMING HOLIDAY WEEKEND IS BELOW. DEPENDING ON FRONTAL TIMING... REACHING RECORD HIGHS ON MONDAY IS POSSIBLE...BUT CONFIDENCE IS LOWER THAN REACHING RECORD HIGHS ON SUNDAY. RECORDS FOR ORD... HIGH TEMP/YEAR HIGH MINIMUM TEMP/YEAR SAT MAY 26TH 94/1911 75/1914 SUN MAY 27TH 94/1911 75/1911 MON MAY 28TH 93/1977 74/2006 RECORDS FOR RFD... SAT MAY 26TH 92/1911 67/1991 SUN MAY 27TH 92/1978 71/1914 MON MAY 28TH 93/2006 69/2006 CMS && .FIRE WEATHER... 451 PM CDT AS A WARM FRONTAL BOUNDARY CONTINUES TO LIFT NORTH THIS EVENING...IT WILL HELP USHER A MUCH WARMER AIR MASS AND MORE MOIST ENVIRONMENT NORTH ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. DESPITE HIGHER MOISTURE AIR SHIFTING NORTH...COULD STILL OBSERVE SOME LOW RELATIVE HUMIDITY VALUES AROUND THE 35 PERCENT AREA SUNDAY AFTERNOON ALONG AND SOUTH OF INTERSTATE 80 AS STRONG MIXING AND HIGH DEWPOINT DEPRESSIONS WILL BE IN PLACE. ALTHOUGH...NOT EXPECTING THE WINDS TO BE TOO STRONG IN THESE LOCATIONS WITH 20FT WINDS EXPECTED TO TOP OFF AT 10-15MPH IN THE AFTERNOON. SIMILAR TEMP AND DEWPOINT CONDITIONS ARE EXPECTED ON MONDAY...ALTHOUGH NOT QUITE AS WARM. NONETHELESS...LOW RELATIVE HUMIDITY VALUES OF 30-35 PERCENT ARE STILL EXPECTED. STRONGER WINDS WILL ALSO BE IN PLACE MONDAY AFTERNOON AS LOW PRESSURE AND A COLD FRONTAL BOUNDARY APPROACH FROM THE WEST...WITH 20FT WINDS EXPECTED TO BE CLOSER TO 20MPH. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 22Z... * NE WINDS EXPECTED TO CONTINUE THROUGH MID EVENING. GUSTS AROUND 20 KT POSSIBLE TIL 00Z OR SO. * LOW CHANCE FOR ISOLD/SCT SHRA/TSRA NEAR THE TERMINALS EARLY THIS EVENING. * SOUTH WINDS TO START SUNDAY BECOMING GUSTY 20-25 KT SUNDAY AFTERNOON. MDB //DISCUSSION...UPDATED 22Z... WINDS HAVE SHIFTED NORTHEAST ACROSS THE TERMINALS THANKS TO THE PASSAGE OF A BOUNDARY THAT MAY BE A SECOND LAKE BREEZE BOUNDARY. EXPECT THAT THESE NORTHEAST WINDS WILL CONTINUE THROUGH EARLY OR MID EVENING BEFORE TURNING SOUTHEASTERLY MID OR LATE EVENING. THIS WILL BE DEPENDENT ON THE WARM FRONT THAT IS SOUTH OF THE TERMINALS AND IT APPEARS ITS NORTHWARD MOVEMENT WILL BE STALLED BY THE COOLING THAT HAS DEVELOPED OFF THE LAKE. A PORTION OF THE FRONT MAY LIFT NORTHWARD WHILE SECTIONS CLOSER TO LAKE MICHIGAN REMAINS HUNG UP SO RFD COULD SEE A SHIFT TO SOUTHERLY WINDS FIRST. WILL CONTINUE MONITOR TIMING OF WIND TRENDS INTO THE EVENING. SHRA/TSRA STILL POSSIBLE BUT CHANCE CONTINUES TO LOOK LOW. MOST FAVORED AREA WOULD BE FROM RFD TO PWK AND POINTS NORTH INTO MID EVENING. MDB FROM 18Z... WARM FRONTAL BOUNDARY CONTINUES TO SLOWLY LIFT NORTH ACROSS SOUTHEAST IOWA STRETCHING EAST THROUGH CENTRAL IL/IN. WINDS NORTH OF THIS BOUNDARY AND ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS CONTINUES TO BE EASTERLY WITH OCCASIONAL GUSTS INTO THE MID/UPR TEENS. SOUTH OF THE BOUNDARY WINDS VEER SOUTHEAST/SOUTH. VISIBLE IMAGERY WAS INDICATING A NARROW CHANNEL OF A CUMULUS FIELDS...HOWEVER IT APPEARS TO REMAIN RATHER FLAT. SOME BETTER GROWTH IN THE CLOUDS EXISTS ACROSS SOUTHEAST MN/WESTERN WI/FAR NORTHERN IA. THIS AREA OF CONVECTION HAS POSED SOME CONCERN FOR NORTHERN IL AIRFIELDS LATER THIS AFTN/EVE...HOWEVER THE GENERAL THINKING IS THAT THIS WILL SLIDE EAST AND AVOID MOST OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...IF NOT ALL OF THEM. AT THIS TIME HAVE GONE WITH A DRY FORECAST...WITH JUST A FEW/SCT CLOUDS ARND 5KFT AGL. BASED ON MODEL SOUNDINGS A THIN MOISTURE LAYER WAS NOTED AT 5KFT AGL...AND THEN DRIES AS THE WARM AIR ADVECTS OVER THE REGION. THIS SHOULD AID IN LIMITING THE CHANCES FOR SHOWERS AND THUNDERSTORMS LATER. THEN AS THE BOUNDARY LIFTS NORTH INTO SOUTHERN WISC...WINDS WILL REMAIN SOUTHERLY THROUGH THE REMAINDER OF THE OVERNIGHT AND SUNDAY PERIOD. WINDS WILL BECOME BETTER MIXED DURING THE DAY SUN..AND CAN EASILY SEE WINDS GUSTING TO 20-25KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 22Z... * HIGH CONFIDENCE IN NE WINDS CONTINUING THROUGH 00Z...MEDIUM-HIGH CONFIDENCE THROUGH MID EVENING. * HIGH CONFIDENCE THAT THREAT FOR SHRA/TSRA IS LOW THIS EVENING. * HIGH CONFIDENCE IN WX TRENDS OVERNIGHT AND SUNDAY. MDB //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...SOUTHWEST WINDS POSSIBLY GUSTING OVER 30KT. CHANCE OF TSRA AT NIGHT...OTHERWISE VFR TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SHRA. FRIDAY...VFR. IZZI && .MARINE... 247 PM CDT A LARGE AREA OF HIGH PRESSURE WILL REMAIN OVER ONTARIO AND WESTERN QUEBEC TONIGHT. LOW PRESSURE MOVES EAST ACROSS THE CENTRAL ROCKIES AND THEN NORTHEAST TO SOUTH DAKOTA OVERNIGHT... LIFTING A WARM FRONT NORTH OVER THE SOUTHERN PORTION OF LAKE MICHIGAN. THE HIGH WILL DRIFT NORTH AND BE CENTERED OVER SOUTHERN HUDSON BAY BY SUNDAY EVENING WHILE THE LOW MOVES VERY SLOWLY NORTH-NORTHEAST TO EASTERN NORTH DAKOTA AND THE WARM FRONT CONTINUING TO MOVE NORTH ACROSS NORTHERN LAKE MICHIGAN. SOUTHEAST TO SOUTH WINDS WILL STRENGTHEN A BIT DUE TO THE INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND LOW PRESSURE AREAS BUT DUE TO THE STABILIZING EFFECT OF THE COOL WATER UNDER VERY WARM AIR...PREVAILING SPEEDS ARE NOT EXPECTED TO 15-20KT. THE LOW MOVES TRACKS EASTWARD JUST NORTH OF THE NORTHERN GREAT LAKES REGION SUNDAY NIGHT THROUGH MONDAY NIGHT SWEEPING A COLD FRONT THROUGH THE WESTERN AND CENTRAL GREAT LAKES LATER MONDAY AND MONDAY NIGHT SHIFTING WINDS TO OUT OF THE WEST AND NORTHWEST FOR TUESDAY. AS THE LOW CONTINUES EAST TO QUEBEC ON TUESDAY A RIDGE OF HIGH PRESSURE BUILDS SOUTH FROM CENTRAL CANADA ACROSS THE NORTHERN AND CENTRAL PLAINS. AS THE RIDGE EVENTUALLY DRIFTS EASTWARD WEDNESDAY AND OVER THE UPPER MIDWEST AND WESTERN GREAT LAKES THURSDAY WINDS DROP OFF TO 10 KT OR LESS AS THE CENTER OF THE HIGH APPROACHES. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
451 PM CDT SAT MAY 26 2012 .DISCUSSION... 338 PM CDT MAIN FORECAST CHALLENGES ARE WITH A WARMING TREND STILL ON TRACK AND MUCH WARMER CONDITIONS FOR THE ENTIRE CWA EXPECTED SUNDAY AND MONDAY...WITH THUNDERSTORM CHANCES LATE THIS AFTERNOON AND EARLY EVENING STILL POSSIBLE MAINLY FOR AREAS ACROSS FAR NORTHERN ILLINOIS. ONGOING CHANGES ACROSS THE CWA THIS AFTERNOON AS A MUCH WARMER AIRMASS CONTINUES TO MOVE NORTH ACROSS THE CENTRAL CONUS THIS AFTERNOON. AS HEIGHTS ALOFT SLOWLY RISE THIS AFTERNOON...SURFACE LOW OVER THE CENTRAL PLAINS CONTINUES TO DEVELOP WITH SURFACE WARM FRONT PUSHING NORTH THROUGH THE REGION. LATEST SURFACE ANALYSIS SHOWING WARM FRONT PUSHING NORTH THROUGH AREAS NEAR STERLING IN NORTHWEST ILLINOIS SOUTHEAST TO AREAS NEAR KANKAKEE. PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS THE ENTIRE CWA TODAY WITH TEMPERATURES REMAINING IN THE 70S AND LOW 80S NORTH OF THE FRONT...WITH TEMPERATURES QUICKLY RISING TO THE UPPER 80S TO LOW 90S SOUTH OF THE FRONT. THIS FRONT WILL CONTINUE LIFTING NORTH THIS EVENING WITH STEADY IF NOT WARMING TEMPS THROUGH THE OVERNIGHT HOURS AND EARLY MORNING TIME FRAME SUNDAY MORNING. THUS...PAVING THE WAY FOR A WARM NEXT COUPLE OF DAYS WITH CURRENT FORECAST HIGH TEMPERATURES STILL ON TRACK. STRONG WARM AIR ADVECTION CURRENTLY ONGOING ACROSS OVER THE ENTIRE REGION WILL CONTINUE WITH MAIN THERMAL AXIS SHIFTING OVERHEAD ON SUNDAY BRINGING 850MB TEMPS OF 20-22C ACROSS THE CWA. THIS COINCIDING WITH FULL SUNSHINE AND STRONG MIXING OF SOUTH/SOUTHWEST FLOW...WILL ALL AID IN TEMPERATURES RISING INTO THE MID AND UPPER 90S ON SUNDAY...WITH STRONG FLOW KEEPING ANY LAKE BREEZE AT BAY AND WARMER TEMPERATURES TO BE OBSERVED THROUGHOUT THE ENTIRE CWA. TEMPERATURES IN THE 90S EXPECTED ONCE AGAIN ON MONDAY BUT NOT QUITE AS HIGH DUE TO PRECIP/CLOUD COVER ISSUES WITH SURFACE WAVE AND FRONTAL BOUNDARY APPROACHING FROM THE WEST. AFTER A COMPLEX OF SHOWERS AND THUNDERSTORMS PUSHED EAST ACROSS AREAS IN NORTHERN ILLINOIS THIS MORNING...THE CWA HAS REMAINED MOSTLY DRY THIS AFTERNOON. DESPITE THIS DRY TREND THUS FAR...STILL FEEL THAT THERE IS A POSSIBILITY FOR AREAS ACROSS FAR NORTHERN ILLINOIS TO OBSERVE SOME SHOWERS AND THUNDERSTORMS...WITH STILL AN ISOLATED SEVERE THREAT REMAINING. ALL MODEL GUIDANCE TODAY AS BEEN USELESS WITH MOST GUIDANCE CONTINUING TO GENERATE CONVECTION WHERE THERE HAS BEEN NONE...AND MOSTLY LIKELY NOT BE. DESPITE A FRONTAL BOUNDARY/IMPETUS FOR CONVECTION LIFTING NORTH ACROSS THE REGION AND SURGE OF GOOD MOISTURE MAKING ITS WAY NORTH...WARMING ALOFT HAS LIMITED UPDRAFT DEVELOPMENT. LATEST RUC ANALYSIS INDICATING THAT 700MB TEMPS OF 10-12C ARE PUSHING OVERHEAD...WHICH IN THE ABSENCE OF BOTH GOOD SURFACE LIFT AND LARGE SCALE ASCENT...HAS LIMITED ANY THUNDERSTORM DEVELOPMENT TODAY. THIS HAS BEEN NOTED WITH THE SHOWERS WHICH HAVE BEEN TRYING TO GET GOING ACROSS IOWA...WHICH ARE ALREADY DISSIPATING. FEEL THAT THE ONLY CHANCE FOR THE CWA TO OBSERVE THUNDERSTORM DEVELOPMENT THIS AFTERNOON WILL BE ACROSS FAR NORTHERN ILLINOIS. HAVE BEEN MONITORING CONVECTION ACROSS SOUTHEAST MINNESOTA AND WESTERN ILLINOIS AND FEEL THAT THIS IS THE AREA WHICH MAY HELP STEER CONVECTION SOUTHWARD. AS A MID LEVEL IMPULSE CONTINUES TO PROGRESS TO THE EAST/NORTHEAST INTO SOUTHERN WISCONSIN...THIS COULD PROVIDE LARGE SCALE ASCENT WHICH COULD THEN INTERACT WITH A NORTHWARD SURGING WARM FRONT. SOME DEVELOPMENT ALONG THE SOUTHERN PORTION OF THIS COMPLEX HAS BEEN OBSERVED THIS AFTERNOON AND CONTINUES TO SEEM PROBABLE FOR THE REMAINDER OF THE AFTERNOON AND EARLY AFTERNOON WITH THE AFOREMENTIONED SYNOPTIC DETAILS COMING INTO BETTER LINE. MOISTURE ADVECTION NORTH COULD HELP FEED THIS DEVELOPMENT AND EVEN HELP STEER ANY CONVECTION FURTHER SOUTHEAST. IF THIS DEVELOPMENT WERE TO SHIFT SOUTH INTO THE NORTHERN PORTIONS OF THE CWA...AN OUTSIDE WIND AND HAIL THREAT COULD STILL BE POSSIBLE AS STEEP MID LEVEL LAPSE RATES REMAIN. RIGHT NOW...THIS IS THE LOW END SOLUTION BUT STILL A POSSIBILITY THAT NEEDS TO CONTINUE TO BE MONITORED. RODRIGUEZ && .CLIMATE... ...RECORD BREAKING HIGH TEMPERATURES EXPECTED SUNDAY MAY 27TH... 302 PM...CURRENTLY FORECASTING A NEW RECORD HIGH AT ORD OF 96 ON SUNDAY...MAY 27TH. THE ORD RECORD HIGH FOR MAY 27TH IS 94 SET IN 1911. THE EARLIEST OCCURRENCE OF 96 DEGREES OR HIGHER IN CHICAGO IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 98 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 96...OR HIGHER...ON SUNDAY MAY 27TH...IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. CURRENTLY FORECASTING A NEW RECORD HIGH OF 98 AT RFD ON SUNDAY... MAY 27TH. THE RFD RECORD HIGH FOR MAY 27TH IS 92 SET IN 1978. THE EARLIEST OCCURRENCE OF 98 DEGREES OR HIGHER IN ROCKFORD IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 106 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 98...OR HIGHER...ON SUNDAY MAY 27TH... IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. A LIST OF RECORD HIGH TEMPS AND RECORD HIGH MINIMUM TEMPS FOR THE UPCOMING HOLIDAY WEEKEND IS BELOW. DEPENDING ON FRONTAL TIMING... REACHING RECORD HIGHS ON MONDAY IS POSSIBLE...BUT CONFIDENCE IS LOWER THAN REACHING RECORD HIGHS ON SUNDAY. RECORDS FOR ORD... HIGH TEMP/YEAR HIGH MINIMUM TEMP/YEAR SAT MAY 26TH 94/1911 75/1914 SUN MAY 27TH 94/1911 75/1911 MON MAY 28TH 93/1977 74/2006 RECORDS FOR RFD... SAT MAY 26TH 92/1911 67/1991 SUN MAY 27TH 92/1978 71/1914 MON MAY 28TH 93/2006 69/2006 CMS && .FIRE WEATHER... 451 PM CDT AS A WARM FRONTAL BOUNDARY CONTINUES TO LIFT NORTH THIS EVENING...IT WILL HELP USHER A MUCH WARMER AIR MASS AND MORE MOIST ENVIRONMENT NORTH ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA. DESPITE HIGHER MOISTURE AIR SHIFTING NORTH...COULD STILL OBSERVE SOME LOW RELATIVE HUMIDITY VALUES AROUND THE 35 PERCENT AREA SUNDAY AFTERNOON ALONG AND SOUTH OF INTERSTATE 80 AS STRONG MIXING AND HIGH DEWPOINT DEPRESSIONS WILL BE IN PLACE. ALTHOUGH...NOT EXPECTING THE WINDS TO BE TOO STRONG IN THESE LOCATIONS WITH 20FT WINDS EXPECTED TO TOP OFF AT 10-15MPH IN THE AFTERNOON. SIMILAR TEMP AND DEWPOINT CONDITIONS ARE EXPECTED ON MONDAY...ALTHOUGH NOT QUITE AS WARM. NONETHELESS...LOW RELATIVE HUMIDITY VALUES OF 30-35 PERCENT ARE STILL EXPECTED. STRONGER WINDS WILL ALSO BE IN PLACE MONDAY AFTERNOON AS LOW PRESSURE AND A COLD FRONTAL BOUNDARY APPROACH FROM THE WEST...WITH 20FT WINDS EXPECTED TO BE CLOSER TO 20MPH. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * EAST WINDS WITH OCCASIONAL GUSTS TO 16KT THIS AFTN. WINDS THEN VEER SOUTHEAST AND SOUTH TONIGHT. * GUSTY WINDS DEVELOP SUN MIDDAY THROUGH AFTN...WITH GUSTS TO 20-25KT. BEACHLER //DISCUSSION...UPDATED 18Z... WARM FRONTAL BOUNDARY CONTINUES TO SLOWLY LIFT NORTH ACROSS SOUTHEAST IOWA STRETCHING EAST THROUGH CENTRAL IL/IN. WINDS NORTH OF THIS BOUNDARY AND ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS CONTINUES TO BE EASTERLY WITH OCCASIONAL GUSTS INTO THE MID/UPR TEENS. SOUTH OF THE BOUNDARY WINDS VEER SOUTHEAST/SOUTH. VISIBLE IMAGERY WAS INDICATING A NARROW CHANNEL OF A CUMULUS FIELDS...HOWEVER IT APPEARS TO REMAIN RATHER FLAT. SOME BETTER GROWTH IN THE CLOUDS EXISTS ACROSS SOUTHEAST MN/WESTERN WI/FAR NORTHERN IA. THIS AREA OF CONVECTION HAS POSED SOME CONCERN FOR NORTHERN IL AIRFIELDS LATER THIS AFTN/EVE...HOWEVER THE GENERAL THINKING IS THAT THIS WILL SLIDE EAST AND AVOID MOST OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...IF NOT ALL OF THEM. AT THIS TIME HAVE GONE WITH A DRY FORECAST...WITH JUST A FEW/SCT CLOUDS ARND 5KFT AGL. BASED ON MODEL SOUNDINGS A THIN MOISTURE LAYER WAS NOTED AT 5KFT AGL...AND THEN DRIES AS THE WARM AIR ADVECTS OVER THE REGION. THIS SHOULD AID IN LIMITING THE CHANCES FOR SHOWERS AND THUNDERSTORMS LATER. THEN AS THE BOUNDARY LIFTS NORTH INTO SOUTHERN WISC...WINDS WILL REMAIN SOUTHERLY THROUGH THE REMAINDER OF THE OVERNIGHT AND SUNDAY PERIOD. WINDS WILL BECOME BETTER MIXED DURING THE DAY SUN..AND CAN EASILY SEE WINDS GUSTING TO 20-25KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN WIND DIR/SPEED. * MEDIUM/HIGH CONFIDENCE IN AIRFIELDS REMAINING DRY. * HIGH CONFIDENCE IN ALL ELEMENTS AFT 09Z SUN. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...SOUTHWEST WINDS POSSIBLY GUSTING OVER 30KT. CHANCE OF TSRA AT NIGHT...OTHERWISE VFR TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SHRA. FRIDAY...VFR. IZZI && .MARINE... 247 PM CDT A LARGE AREA OF HIGH PRESSURE WILL REMAIN OVER ONTARIO AND WESTERN QUEBEC TONIGHT. LOW PRESSURE MOVES EAST ACROSS THE CENTRAL ROCKIES AND THEN NORTHEAST TO SOUTH DAKOTA OVERNIGHT... LIFTING A WARM FRONT NORTH OVER THE SOUTHERN PORTION OF LAKE MICHIGAN. THE HIGH WILL DRIFT NORTH AND BE CENTERED OVER SOUTHERN HUDSON BAY BY SUNDAY EVENING WHILE THE LOW MOVES VERY SLOWLY NORTH-NORTHEAST TO EASTERN NORTH DAKOTA AND THE WARM FRONT CONTINUING TO MOVE NORTH ACROSS NORTHERN LAKE MICHIGAN. SOUTHEAST TO SOUTH WINDS WILL STRENGTHEN A BIT DUE TO THE INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND LOW PRESSURE AREAS BUT DUE TO THE STABILIZING EFFECT OF THE COOL WATER UNDER VERY WARM AIR...PREVAILING SPEEDS ARE NOT EXPECTED TO 15-20KT. THE LOW MOVES TRACKS EASTWARD JUST NORTH OF THE NORTHERN GREAT LAKES REGION SUNDAY NIGHT THROUGH MONDAY NIGHT SWEEPING A COLD FRONT THROUGH THE WESTERN AND CENTRAL GREAT LAKES LATER MONDAY AND MONDAY NIGHT SHIFTING WINDS TO OUT OF THE WEST AND NORTHWEST FOR TUESDAY. AS THE LOW CONTINUES EAST TO QUEBEC ON TUESDAY A RIDGE OF HIGH PRESSURE BUILDS SOUTH FROM CENTRAL CANADA ACROSS THE NORTHERN AND CENTRAL PLAINS. AS THE RIDGE EVENTUALLY DRIFTS EASTWARD WEDNESDAY AND OVER THE UPPER MIDWEST AND WESTERN GREAT LAKES THURSDAY WINDS DROP OFF TO 10 KT OR LESS AS THE CENTER OF THE HIGH APPROACHES. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
342 PM CDT SAT MAY 26 2012 .DISCUSSION... 338 PM CDT MAIN FORECAST CHALLENGES ARE WITH A WARMING TREND STILL ON TRACK AND MUCH WARMER CONDITIONS FOR THE ENTIRE CWA EXPECTED SUNDAY AND MONDAY...WITH THUNDERSTORM CHANCES LATE THIS AFTERNOON AND EARLY EVENING STILL POSSIBLE MAINLY FOR AREAS ACROSS FAR NORTHERN ILLINOIS. ONGOING CHANGES ACROSS THE CWA THIS AFTERNOON AS A MUCH WARMER AIRMASS CONTINUES TO MOVE NORTH ACROSS THE CENTRAL CONUS THIS AFTERNOON. AS HEIGHTS ALOFT SLOWLY RISE THIS AFTERNOON...SURFACE LOW OVER THE CENTRAL PLAINS CONTINUES TO DEVELOP WITH SURFACE WARM FRONT PUSHING NORTH THROUGH THE REGION. LATEST SURFACE ANALYSIS SHOWING WARM FRONT PUSHING NORTH THROUGH AREAS NEAR STERLING IN NORTHWEST ILLINOIS SOUTHEAST TO AREAS NEAR KANKAKEE. PARTLY CLOUDY SKIES HAVE BEEN OBSERVED ACROSS THE ENTIRE CWA TODAY WITH TEMPERATURES REMAINING IN THE 70S AND LOW 80S NORTH OF THE FRONT...WITH TEMPERATURES QUICKLY RISING TO THE UPPER 80S TO LOW 90S SOUTH OF THE FRONT. THIS FRONT WILL CONTINUE LIFTING NORTH THIS EVENING WITH STEADY IF NOT WARMING TEMPS THROUGH THE OVERNIGHT HOURS AND EARLY MORNING TIME FRAME SUNDAY MORNING. THUS...PAVING THE WAY FOR A WARM NEXT COUPLE OF DAYS WITH CURRENT FORECAST HIGH TEMPERATURES STILL ON TRACK. STRONG WARM AIR ADVECTION CURRENTLY ONGOING ACROSS OVER THE ENTIRE REGION WILL CONTINUE WITH MAIN THERMAL AXIS SHIFTING OVERHEAD ON SUNDAY BRINGING 850MB TEMPS OF 20-22C ACROSS THE CWA. THIS COINCIDING WITH FULL SUNSHINE AND STRONG MIXING OF SOUTH/SOUTHWEST FLOW...WILL ALL AID IN TEMPERATURES RISING INTO THE MID AND UPPER 90S ON SUNDAY...WITH STRONG FLOW KEEPING ANY LAKE BREEZE AT BAY AND WARMER TEMPERATURES TO BE OBSERVED THROUGHOUT THE ENTIRE CWA. TEMPERATURES IN THE 90S EXPECTED ONCE AGAIN ON MONDAY BUT NOT QUITE AS HIGH DUE TO PRECIP/CLOUD COVER ISSUES WITH SURFACE WAVE AND FRONTAL BOUNDARY APPROACHING FROM THE WEST. AFTER A COMPLEX OF SHOWERS AND THUNDERSTORMS PUSHED EAST ACROSS AREAS IN NORTHERN ILLINOIS THIS MORNING...THE CWA HAS REMAINED MOSTLY DRY THIS AFTERNOON. DESPITE THIS DRY TREND THUS FAR...STILL FEEL THAT THERE IS A POSSIBILITY FOR AREAS ACROSS FAR NORTHERN ILLINOIS TO OBSERVE SOME SHOWERS AND THUNDERSTORMS...WITH STILL AN ISOLATED SEVERE THREAT REMAINING. ALL MODEL GUIDANCE TODAY AS BEEN USELESS WITH MOST GUIDANCE CONTINUING TO GENERATE CONVECTION WHERE THERE HAS BEEN NONE...AND MOSTLY LIKELY NOT BE. DESPITE A FRONTAL BOUNDARY/IMPETUS FOR CONVECTION LIFTING NORTH ACROSS THE REGION AND SURGE OF GOOD MOISTURE MAKING ITS WAY NORTH...WARMING ALOFT HAS LIMITED UPDRAFT DEVELOPMENT. LATEST RUC ANALYSIS INDICATING THAT 700MB TEMPS OF 10-12C ARE PUSHING OVERHEAD...WHICH IN THE ABSENCE OF BOTH GOOD SURFACE LIFT AND LARGE SCALE ASCENT...HAS LIMITED ANY THUNDERSTORM DEVELOPMENT TODAY. THIS HAS BEEN NOTED WITH THE SHOWERS WHICH HAVE BEEN TRYING TO GET GOING ACROSS IOWA...WHICH ARE ALREADY DISSIPATING. FEEL THAT THE ONLY CHANCE FOR THE CWA TO OBSERVE THUNDERSTORM DEVELOPMENT THIS AFTERNOON WILL BE ACROSS FAR NORTHERN ILLINOIS. HAVE BEEN MONITORING CONVECTION ACROSS SOUTHEAST MINNESOTA AND WESTERN ILLINOIS AND FEEL THAT THIS IS THE AREA WHICH MAY HELP STEER CONVECTION SOUTHWARD. AS A MID LEVEL IMPULSE CONTINUES TO PROGRESS TO THE EAST/NORTHEAST INTO SOUTHERN WISCONSIN...THIS COULD PROVIDE LARGE SCALE ASCENT WHICH COULD THEN INTERACT WITH A NORTHWARD SURGING WARM FRONT. SOME DEVELOPMENT ALONG THE SOUTHERN PORTION OF THIS COMPLEX HAS BEEN OBSERVED THIS AFTERNOON AND CONTINUES TO SEEM PROBABLE FOR THE REMAINDER OF THE AFTERNOON AND EARLY AFTERNOON WITH THE AFOREMENTIONED SYNOPTIC DETAILS COMING INTO BETTER LINE. MOISTURE ADVECTION NORTH COULD HELP FEED THIS DEVELOPMENT AND EVEN HELP STEER ANY CONVECTION FURTHER SOUTHEAST. IF THIS DEVELOPMENT WERE TO SHIFT SOUTH INTO THE NORTHERN PORTIONS OF THE CWA...AN OUTSIDE WIND AND HAIL THREAT COULD STILL BE POSSIBLE AS STEEP MID LEVEL LAPSE RATES REMAIN. RIGHT NOW...THIS IS THE LOW END SOLUTION BUT STILL A POSSIBILITY THAT NEEDS TO CONTINUE TO BE MONITORED. RODRIGUEZ && .CLIMATE... ...RECORD BREAKING HIGH TEMPERATURES EXPECTED SUNDAY MAY 27TH... 302 PM...CURRENTLY FORECASTING A NEW RECORD HIGH AT ORD OF 96 ON SUNDAY...MAY 27TH. THE ORD RECORD HIGH FOR MAY 27TH IS 94 SET IN 1911. THE EARLIEST OCCURRENCE OF 96 DEGREES OR HIGHER IN CHICAGO IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 98 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 96...OR HIGHER...ON SUNDAY MAY 27TH...IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. CURRENTLY FORECASTING A NEW RECORD HIGH OF 98 AT RFD ON SUNDAY... MAY 27TH. THE RFD RECORD HIGH FOR MAY 27TH IS 92 SET IN 1978. THE EARLIEST OCCURRENCE OF 98 DEGREES OR HIGHER IN ROCKFORD IS ON MAY 31ST 1934 WHEN A RECORD HIGH OF 106 WAS REACHED. THUS...IF THE TEMPERATURE DOES REACH 98...OR HIGHER...ON SUNDAY MAY 27TH... IT WILL BECOME THE WARMEST TEMPERATURE THIS EARLY IN THE YEAR. A LIST OF RECORD HIGH TEMPS AND RECORD HIGH MINIMUM TEMPS FOR THE UPCOMING HOLIDAY WEEKEND IS BELOW. DEPENDING ON FRONTAL TIMING... REACHING RECORD HIGHS ON MONDAY IS POSSIBLE...BUT CONFIDENCE IS LOWER THAN REACHING RECORD HIGHS ON SUNDAY. RECORDS FOR ORD... HIGH TEMP/YEAR HIGH MINIMUM TEMP/YEAR SAT MAY 26TH 94/1911 75/1914 SUN MAY 27TH 94/1911 75/1911 MON MAY 28TH 93/1977 74/2006 RECORDS FOR RFD... SAT MAY 26TH 92/1911 67/1991 SUN MAY 27TH 92/1978 71/1914 MON MAY 28TH 93/2006 69/2006 CMS && .FIRE WEATHER... 706 AM CDT A COLD FRONT WILL APPROACH THE REGION MONDAY WITH GUSTY SOUTHERLY WINDS DEVELOPING AHEAD OF THE FRONT MONDAY AFTERNOON. DEW POINTS ARE EXPECTED TO BE IN THE LOW 60S //RELATIVE HUMIDITIES OF 30 TO 40 PERCENT// MONDAY AFTERNOON. THIS IS ASSUMING THAT CLOUD COVER WILL DEVELOP AHEAD OF THE ADVANCING COLD FRONT. HOWEVER...THERE IS A CONCERN THAT CLOUD COVER MAY BE LOWER THAN ANTICIPATED LEADING TO WARMER SURFACE TEMPERATURES AND DRIER DEW POINTS GIVEN DEEPER MIXING WITH A THREAT OF REACHING RED FLAG WARNING CRITERIA. BMD && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * EAST WINDS WITH OCCASIONAL GUSTS TO 16KT THIS AFTN. WINDS THEN VEER SOUTHEAST AND SOUTH TONIGHT. * GUSTY WINDS DEVELOP SUN MIDDAY THROUGH AFTN...WITH GUSTS TO 20-25KT. BEACHLER //DISCUSSION...UPDATED 18Z... WARM FRONTAL BOUNDARY CONTINUES TO SLOWLY LIFT NORTH ACROSS SOUTHEAST IOWA STRETCHING EAST THROUGH CENTRAL IL/IN. WINDS NORTH OF THIS BOUNDARY AND ACROSS NORTHERN IL/NORTHWEST IN AIRFIELDS CONTINUES TO BE EASTERLY WITH OCCASIONAL GUSTS INTO THE MID/UPR TEENS. SOUTH OF THE BOUNDARY WINDS VEER SOUTHEAST/SOUTH. VISIBLE IMAGERY WAS INDICATING A NARROW CHANNEL OF A CUMULUS FIELDS...HOWEVER IT APPEARS TO REMAIN RATHER FLAT. SOME BETTER GROWTH IN THE CLOUDS EXISTS ACROSS SOUTHEAST MN/WESTERN WI/FAR NORTHERN IA. THIS AREA OF CONVECTION HAS POSED SOME CONCERN FOR NORTHERN IL AIRFIELDS LATER THIS AFTN/EVE...HOWEVER THE GENERAL THINKING IS THAT THIS WILL SLIDE EAST AND AVOID MOST OF THE NORTHERN IL/NORTHWEST IN AIRFIELDS...IF NOT ALL OF THEM. AT THIS TIME HAVE GONE WITH A DRY FORECAST...WITH JUST A FEW/SCT CLOUDS ARND 5KFT AGL. BASED ON MODEL SOUNDINGS A THIN MOISTURE LAYER WAS NOTED AT 5KFT AGL...AND THEN DRIES AS THE WARM AIR ADVECTS OVER THE REGION. THIS SHOULD AID IN LIMITING THE CHANCES FOR SHOWERS AND THUNDERSTORMS LATER. THEN AS THE BOUNDARY LIFTS NORTH INTO SOUTHERN WISC...WINDS WILL REMAIN SOUTHERLY THROUGH THE REMAINDER OF THE OVERNIGHT AND SUNDAY PERIOD. WINDS WILL BECOME BETTER MIXED DURING THE DAY SUN..AND CAN EASILY SEE WINDS GUSTING TO 20-25KT. BEACHLER //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN WIND DIR/SPEED. * MEDIUM/HIGH CONFIDENCE IN AIRFIELDS REMAINING DRY. * HIGH CONFIDENCE IN ALL ELEMENTS AFT 09Z SUN. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z MONDAY-12Z SATURDAY...UPDATED 12Z... SUNDAY NIGHT...VFR. MONDAY...SOUTHWEST WINDS POSSIBLY GUSTING OVER 30KT. CHANCE OF TSRA AT NIGHT...OTHERWISE VFR TUESDAY...VFR. WEDNESDAY...VFR. THURSDAY...CHANCE OF SHRA. FRIDAY...VFR. IZZI && .MARINE... 247 PM CDT A LARGE AREA OF HIGH PRESSURE WILL REMAIN OVER ONTARIO AND WESTERN QUEBEC TONIGHT. LOW PRESSURE MOVES EAST ACROSS THE CENTRAL ROCKIES AND THEN NORTHEAST TO SOUTH DAKOTA OVERNIGHT... LIFTING A WARM FRONT NORTH OVER THE SOUTHERN PORTION OF LAKE MICHIGAN. THE HIGH WILL DRIFT NORTH AND BE CENTERED OVER SOUTHERN HUDSON BAY BY SUNDAY EVENING WHILE THE LOW MOVES VERY SLOWLY NORTH-NORTHEAST TO EASTERN NORTH DAKOTA AND THE WARM FRONT CONTINUING TO MOVE NORTH ACROSS NORTHERN LAKE MICHIGAN. SOUTHEAST TO SOUTH WINDS WILL STRENGTHEN A BIT DUE TO THE INCREASING PRESSURE GRADIENT BETWEEN THE HIGH AND LOW PRESSURE AREAS BUT DUE TO THE STABILIZING EFFECT OF THE COOL WATER UNDER VERY WARM AIR...PREVAILING SPEEDS ARE NOT EXPECTED TO 15-20KT. THE LOW MOVES TRACKS EASTWARD JUST NORTH OF THE NORTHERN GREAT LAKES REGION SUNDAY NIGHT THROUGH MONDAY NIGHT SWEEPING A COLD FRONT THROUGH THE WESTERN AND CENTRAL GREAT LAKES LATER MONDAY AND MONDAY NIGHT SHIFTING WINDS TO OUT OF THE WEST AND NORTHWEST FOR TUESDAY. AS THE LOW CONTINUES EAST TO QUEBEC ON TUESDAY A RIDGE OF HIGH PRESSURE BUILDS SOUTH FROM CENTRAL CANADA ACROSS THE NORTHERN AND CENTRAL PLAINS. AS THE RIDGE EVENTUALLY DRIFTS EASTWARD WEDNESDAY AND OVER THE UPPER MIDWEST AND WESTERN GREAT LAKES THURSDAY WINDS DROP OFF TO 10 KT OR LESS AS THE CENTER OF THE HIGH APPROACHES. TRS && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$
AREA FORECAST DISCUSSION
NWS WICHITA KS
1257 PM CDT SAT MAY 26 2012 .UPDATE... WINDS CONTINUE TO INCREASE ACROSS THE REGION THIS MORNING. THE WIND ADVISORY STILL LOOKS GOOD AND ON TRACK TO VERIFY. THERE MAY BE AN HOUR OF CRITERIA MET A BIT FURTHER EAST OF THE CURRENT ADVISORY AREA...BUT CONFIDENCE IN THAT IS NOT THAT GREAT. WILL STICK WITH WHAT WE HAVE AT THE MOMENT. CONVECTION FOR THIS AFTERNOON AND EVENING REMAINS ON TRACK FOR THE MOST PART. THE 26.13 AND 25.14 RUNS OF THE HRRR SHOW CONVECTIVE INITIATION IN SOUTHWEST KANSAS AROUND 22Z WITH TRANSLATION OF ACTIVITY INTO CENTRAL KANSAS BEFORE 02Z. THE MAIN CHALLENGE IS THE ENVIRONMENT WITH THESE STORMS. THE 26.12Z NAM-WRF FORECAST OF 0-6KM SHEAR IN THAT LOCATION IS 30-35 KNOTS. THIS IS ON THE VERY LOW END OF FOR SUPERCELLS. INSTABILITY OF 2-3K OF CAPE IF STRONG ENOUGH TO PRODUCE SOME LARGE HAIL AND DAMAGING WIND. WITH THAT...THINK IT WARRANTS A LOW END RISK OF SEVERE...SO WILL CONTINUES FORECAST RISK OF SEVERE WEATHER AND ACTUALLY BRING IT FURTHER EAST GIVEN THE CAPE/SHEAR IN THAT LOCATION AS WELL AS THE AMOUNT OF MOISTURE SHOWN ON WATER VAPOR IMAGERY. COOK && .AVIATION...Z TAFS KRSL/KSLN/KHUT/KICT/KCNU WINDS WILL CONTINUE TO BE STRONG FROM THE SOUTH FOR THE NEXT FEW DAYS /25G35 KTS OR SO/. THERE SHOULD BE SCATTERED THUNDERSTORMS WEST OF THE KANSAS TURNPIKE. THESE COULD PRODUCE HAIL...STRONG WINDS GREATER THAN 50 KNOTS FROM MICROBURSTS. THE BEST TIME FOR THESE IS FROM 22Z THROUGH 02Z. COOK && .PREV DISCUSSION... /ISSUED 640 AM CDT SAT MAY 26 2012/ AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU BY FAR THE GREATEST CONCERN IS THAT OF STRONG S WINDS THAT ARE LIKELY TO REACH A SUSTAINED 25-30KTS ACROSS ALL OF CNTRL & SC KS EARLY THIS AFTERNOON WITH THE STRONGEST WINDS WHIPPING KRSL WHERE ~40KT GUSTS ARE LIKELY. WITH THE INTENSE SFC CYCLONE LIFTING NE FROM CO TO WRN NEBRASKA THIS EVENING AM NOW EXPECTING MINIMAL DIMINISHMENT IN SPEEDS (ESPECIALLY OVER KRSL WHERE CLOSEST TO THE CYCLONE.) S WINDS MAY EVEN RESTRENGTHEN TOWARD 27/06Z AS LOW-LVL JET PRESSES HARDER ON THROTTLE. THE TSRA THREAT IS LIMITED IN BOTH DURATION & AREAL EXTENT OVER KRSL & AS SUCH HAVE LEFT SUCH MENTION OUT OF THE TAF FOR TIME BEING. PREV DISCUSSION... /ISSUED 313 AM CDT SAT MAY 26 2012/ DISCUSSION... MAIN FORECAST CHALLENGE WILL BE STORM CHANCES SUN AFTERNOON THROUGH MON. SYNOPSIS: DEEP UPPER TROUGH CURRENTLY ENCOMPASSES MOST OF THE WESTERN CONUS. MEANWHILE SOME REMNANT TROPICAL MOISTURE FROM BUD CONTINUES TO STREAM NORTH ACROSS THE SOUTHERN PLAINS. AT THE SURFACE THE WARM FRONT IS NOW SITUATED BETWEEN I-70 AND THE NEBRASKA BORDER. TODAY-TONIGHT: AS THE DEEP UPPER TROUGH WORKS EAST TODAY SURFACE LOW PRESSURE WILL RAPIDLY DEEPEN OVER NORTHEAST CO/SW NEBRASKA. THIS WILL RESULT IN STRONG SOUTH WINDS AND UNSEASONABLY WARM TEMPS ACROSS THE ENTIRE AREA. CONFIDENCE IS INCREASING THAT WE WILL SEE SOME AFTERNOON CONVECTION WEST OF I-135 WHERE CAPPING WILL BE AT A MINIMUM. THIS DEVELOPMENT WILL ALSO BE AIDED BY THE MID LEVEL TROPICAL MOISTURE THAT IS EXPECTED TO CONTINUING STREAMING NORTH. EXTREMELY LARGE TEMP/DEW SPREADS WILL LIMIT ANY SEVERE THREAT TO DOWNBURST WINDS AND HAIL. SOME OF THIS ACTIVITY MAY LINGER INTO THE EARLY EVENING HOURS. WILL RUN WITH A WIND ADVISORY FOR MUCH OF CENTRAL KS THIS AFTERNOON INTO THE EARLY EVENING. AT THIS TIME IT APPEARS THE SOUTHERLY WINDS WILL NOT GET TOO CRANKED UP UNTIL AFTER 19Z WITH THE STRONGEST WINDS EXPECTED ONLY A HOUR OR TWO BEFORE SUNSET. HIGHS TODAY ARE EXPECTED TO BE THE WARMEST THROUGH THIS ENTIRE FORECAST PACKAGE WITH SOME LOCATIONS WEST OF I-135 CLIMBING INTO THE UPPER 90S. SUN-MON: THE SHORTWAVE TROUGH IS STILL EXPECTED TO MOVE OUT INTO THE HIGH PLAINS BY SUN AFTERNOON. STORMS ARE EXPECTED TO DEVELOP BY LATE SUN AFTERNOON ALONG THE DRYLINE WHICH WILL BE JUST WEST OF THE FORECAST AREA. THE COLD FRONT WILL TAKE OVER THE DRYLINE BY EARLY SUN EVENING AND SURGE THROUGH THE AREA SUN NIGHT. THE MAIN QUESTION WILL BE HOW FAR SOUTH THE MORE WIDESPREAD PRECIP MAKES IT. THE GFS CONTINUES TO BE MORE ROBUST IN DIVING SOME OF THE UPPER ENERGY FURTHER SOUTH COMPARED TO THE NAM. WHILE MUCH OF THE AREA SHOULD AT LEAST SEE SOME ISO-SCT SHOWER AND STORM ACTIVITY...FEEL THE MORE WIDESPREAD CONVECTION WILL BE CONFINED TO THE EXTREME NORTH AND NORTHEAST FRINGES OF THE FORECAST AREA. THE FRONT WILL BE SLOW TO MOVE OUT OF SE KS WHICH WILL KEEP SOME STORM CHANCES AROUND FOR MON. TUE-FRI: CONFIDENCE THROUGH THESE EXTENDED PERIODS IS VERY LOW DUE TO PERSISTENT MODEL DISCREPANCIES. WHILE BOTH THE GFS AND ECMWF ARE STILL FORECASTING A TRANSITION TO A NW FLOW REGIME...THE GFS CONTINUES TO BE MORE AGGRESSIVE IN DIGGING THE SHORTWAVE ENERGY FURTHER SOUTH. THEREFORE THE GFS IS MUCH WETTER THAN THE ECMWF BECAUSE IT KEEPS A TIGHT BAROCLINIC ZONE RIGHT OVER THE FORECAST AREA. BY 00Z THU THE GFS IS SLIDING A DECENT SHORTWAVE OVER THE DAKOTAS AND EVENTUALLY INTO THE CENTRAL PLAINS. MEANWHILE THE ECMWF KEEPS THIS PIECE OF ENERGY OVER THE NORTHERN PLAINS AND TRACKS IT INTO THE GREAT LAKES. IT APPEARS THE ECMWF DOES HAVE SOME SUPPORT FROM THE UKMET WHICH DOES LEAD US TO THINK THAT THE GFS MIGHT BE TOO WET. LAWSON && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 95 71 91 69 / 20 20 10 20 HUTCHINSON 95 71 91 67 / 20 20 10 30 NEWTON 94 70 90 68 / 20 20 10 30 ELDORADO 94 70 90 69 / 20 20 10 30 WINFIELD-KWLD 95 71 91 70 / 10 10 10 20 RUSSELL 96 71 90 63 / 30 30 40 60 GREAT BEND 96 71 90 64 / 30 30 30 50 SALINA 98 71 91 66 / 20 20 10 40 MCPHERSON 96 71 91 67 / 20 20 10 30 COFFEYVILLE 93 70 90 70 / 10 10 10 20 CHANUTE 91 69 88 69 / 10 10 10 20 IOLA 91 69 88 69 / 10 10 10 20 PARSONS-KPPF 92 70 89 70 / 10 10 10 20 && .ICT WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ032-033-047-048- 050. && $$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
401 AM CDT SAT MAY 26 2012 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 349 AM CDT SAT MAY 26 2012 TODAY WILL DEFINITELY BECOME VERY WINDY, AND BY 23Z OR 00Z A FEW STRONG STORMS COULD FORM IN OUR NORTHEAST AND CENTRAL ZONES, FROM LACROSSE TO CIMARRON. THESE STORMS WILL FROM JUST NORTH OF A DRY LINE AND THE MOISTURE ADVECTION BETWEEN NOW AND THEN COULD PRODUCE SOME HEAVY RAINFALL, AS MUCH AS 2 INCHES IN SPOTS. THE HRRR MODEL EVEN SUGGESTS A FEW SPOTS OF OVER 3 INCHES ARE POSSIBLE. THE CAPE WILL ALSO BE ELEVATED ENOUGH PER THE NAM MODEL, IN THE 3000 J/KM LEVEL BY 00Z, AND THUS HAIL UP TO TENNIS BALL SIZE IS ALSO A RISK. FOR NOW, I PUT POSSIBLE SEVERE WORDING WITH MODERATE RAIN IN THE PRECIP TYPE, AND PLAN TO GO STRONG ON HEAVY RAIN AND LARGE HAIL IN THE HWO, WITH THE RISK OF AN ISOLATED TORNADO NOT OUT OF THE QUESTION. AS FOR POPS, I UPPED THE POPS IN OUR NORTHEAST TO 40 PERCENT, AND THAT MAY NEED TO BE HEIGHTENED EVEN MORE ONCE AND WHERE THE PRECIP FIRES. OF OTHER CONCERNS, THERE IS A 50 TO 60 KT JET AT 850MB WHICH WILL HAVE LITTLE TROUBLE MIXING DOWN AS THE DAY WARMS UP, SO THE WIND ADVISORY WAS EXPANDED TO INCLUDE ALL OUR COUNTIES, FROM ELKHART TO MEDICINE LODGE AND FROM INGLEWOOD TO HAYS. WINDS WILL BE SOUTH AND INCREASE TOWARDS 17Z INTO THE 30G40 MPH RANGE, FIRST IN THE WEST NEAR THE COLORADO BORDER AND THEN QUICKLY SPREAD TO THE EAST TOWARDS HAYS, PRATT AND KIOWA. WINDS MAY INCREASE STILL MORE DURING THE AFTERNOON HOURS. ICT AND PUB BOTH MADE GOOD POINTS THAT THE ADVISORY (WARNING LEVEL IN PUB`S AREA) COULD EXTEND INTO THE EARLY EVENING. I CHOSE THE END TIME FOR THE WIND ADVISORY AS 02Z, CLOSER TO THE TIME OF SUNDOWN THAN THE 04Z END TIME CHOSEN BY PUB. IT WILL BE HOT AGAIN TODAY, AND HAVE TO WONDER IF ANY SPOTS IN MY FORECAST AREA WILL REACH THE 100F DEGREE MARK. STAYED JUST SHY OF THAT AND THIS IS NEAR ISC MAX TEMPS. I, WENT WITH HIGHS FROM THE MID 90S IN OUR EAST AT SUCH LOCATIONS OF MEDICINE LODGE AND LARNED, AND RANGING UP TO THE UPPER 90S IN OUR WEST NEAR GARDEN CITY AND JOHNSON CITY. THE POPS DECREASED TO 20 PERCENT THIS EVENING, BUT WILL EXIST THROUGH ABOUT 06Z, AS THE DRY LINE (OR WARM FRONT) RECEDES WEST TO NEAR EASTERN COLORADO. WINDS WILL ONLY DECREASE INTO THE 20 TO 25 MPH RANGE, WITH THE GRADIENT STILL TIGHT FROM COLORADO TO CENTRAL KANSAS. THESE WINDS WILL ASSIST IN KEEPING TEMPERATURES FROM FALLING FAST, AND MINIMUM TEMPERATURES SHOULD RANGE FROM THE LOWER TO MID 60S NEAR THE COLORADO BORDER TO THE LOWER 70S FROM HAYS TO SAINT JOHN TO MEDICINE LODGE. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CDT SAT MAY 26 2012 IMMEDIATE CHALLENGES FOR THE MEDIUM RANGE ARE FOCUSED ON THE CONVECTIVE CHANCES, AS WELL AS CONVECTIVE MODES AND THREATS FOR SUNDAY. WATER VAPOR IMAGERY SHOWS A WELL DEFINED TROUGH DROPPING DOWN THE CALIFORNIA COAST, WHICH WILL BE THE UPPER SYSTEM THAT ROTATES THROUGH THE SOUTHWEST STATES AND TOWARD THE CENTRAL HIGH PLAINS THIS WEEKEND. THE ECMWF, GFS AND NAM ALL DEVELOP A ROUGHLY SIMILAR SOLUTION, WHICH CONSISTS OF A STRONG 100 KNOT UPPER JET FROM THE 4 CORNERS REGION THROUGH CENTRAL NEBRASKA ON SUNDAY. A TIGHT UPPER HEIGHT GRADIENT WILL BE FOUND ACROSS THE CENTRAL HIGH PLAINS DURING THIS TIME, AND AN IMPRESSIVE DRYLINE SHOULD PUSH INTO THE FAR WESTERN KANSAS COUNTIES DURING THE MORNING HOURS. A DRYLINE WILL SERVE AS AN IMPRESSIVE SOURCE OF LOW LEVEL MOISTURE CONVERGENCE. SURFACE DEW POINTS WILL BE IN THE MID TO UPPER 60S AHEAD OF THIS FEATURE, AND THE NAM AT THIS TIME IS STILL INDICATING IMPRESSIVE 1.2 TO 1.4 INCH PRECIPITABLE WATER VALUES WHERE THE MOISTURE POOLING IS EVIDENT. THE NAM`S CONVECTIVE PRECIPITATION IS PRIMARILY FOCUSED ACROSS CENTRAL KANSAS AT THIS TIME, BUT IT IS LIKELY THUNDERSTORMS MAY BE OCCURRING ANYWHERE ALONG THE FEATURE AND EASTWARD PAST 00 UTC MONDAY. WITH SUCH A SETUP, TORNADOES, LOCAL FLOODING AND STRONGLY ROTATING STORMS SUPPORTING SEVERE WINDS AND BASEBALL SIZED HAIL OR LARGER MIGHT BE EXPECTED, ESPECIALLY EAST OF A MEAN ELLIS TO MEADE LINE. AFTER THIS THE UPPER LEVEL FLOW BECOMES MORE ZONAL, AND THE IMPRESSIVE BOUNDARY LAYER MOISTURE BECOMES REPLACED BY A MUCH DRIER AIRMASS ON MONDAY. MODELS PRODUCE SURFACE DEW POINTS IN THE 20`S AND 30S BY THAT TIME. A BRIEF RESPITE FROM CONVECTIVE CHANCES ON MONDAY BEFORE THE WINDS VEER STRONGLY ONCE AGAIN AND SPREAD ELEVATED LOW LEVEL THETA-E BACK INTO WESTERN KANSAS ON TUESDAY. AS A RESULT THUNDERSTORM CHANCES CAN BE EXPECTED AGAIN AS EARLY AS TUESDAY MORNING BY SOME NUMERICAL MODELS. A HIGH DEGREE OF MESOSCALE UNCERTAINTY COMES INTO PLAY AT THIS POINT. AN UPPER JET SPREADING SOUTHWARD FROM THE PACIFIC NORTHWEST MAY ACT AS A FOCUS FOR LARGE SCALE LIFT BY MID TO LATE WEEK TO DRIVE MCS ACTIVITY ACROSS THE CENTRAL PLAINS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1226 AM CDT SAT MAY 26 2012 OVERALL, CONDITIONS WILL BE VFR WITH STRONG WINDS SATURDAY. AS A WARM FRONT TO THE NORTH CONTINUES TO MARCH NORTHEASTWARD OVERNIGHT AND SATURDAY, CIRRUS CLOUD AND SOUTHWEST WINDS AT 12G25 KNOTS WILL CONTINUE OVERNIGHT. SOME FOG AS FORMED IN PARTS OF WYOMING AND NORTHERN COLORADO, AND THIS IFR/MVFR FOG MAY SLIP SOUTH LATE TONIGHT AND BRING VSBYS DOWN IN HYS AND GCK TO THE IFR CATEGORY. THESE CONDITIONS WILL IMPROVE BY 13Z, AS A DRY LINE FORMS ACROSS SOUTHWEST KANSAS SATURDAY AND A LOW PRESSURE TROUGH DEEPENS IN THE LEE OF THE ROCKIES. WINDS WILL BE SOUTH SATURDAY AT 26G36 KNOTS. IN ADDITION TO THE WIND, BY LATE IN THE AFTERNOON, THERE IS A CHANCE FOR STRONG STORMS IN THE HYS AND GCK TAF SITES, AND A SLIGHT CHANCE IN THE DDC TAF SITE. I CHOSE TO LEAVE MENTION OF TS OUT OF THE TAFS, SINCE THAT IS 15 HOURS OR SO OUT IN THE TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 96 70 92 62 / 30 20 70 30 GCK 97 69 93 59 / 30 30 30 20 EHA 96 62 90 58 / 20 30 20 10 LBL 96 65 91 60 / 30 20 30 10 HYS 97 72 91 63 / 40 30 80 70 P28 94 72 91 67 / 10 20 70 30 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 9 PM CDT /8 PM MDT/ THIS EVENING FOR KSZ030-031-043>046-061>066-074>081-084>090. && $$ SHORT TERM...BURKE LONG TERM...RUSSELL AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
351 AM CDT SAT MAY 26 2012 ...UPDATED THE SHORT TERM DISCUSSION... .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 349 AM CDT SAT MAY 26 2012 TODAY WILL DEFINITELY BECOME VERY WINDY, AND BY 23Z OR 00Z A FEW STRONG STORMS COULD FORM IN OUR NORTHEAST AND CENTRAL ZONES, FROM LACROSSE TO CIMARRON. THESE STORMS WILL FROM JUST NORTH OF A DRY LINE AND THE MOISTURE ADVECTION BETWEEN NOW AND THEN COULD PRODUCE SOME HEAVY RAINFALL, AS MUCH AS 2 INCHES IN SPOTS. THE HRRR MODEL EVEN SUGGESTS A FEW SPOTS OF OVER 3 INCHES ARE POSSIBLE. THE CAPE WILL ALSO BE ELEVATED ENOUGH PER THE NAM MODEL, IN THE 3000 J/KM LEVEL BY 00Z, AND THUS HAIL UP TO TENNIS BALL SIZE IS ALSO A RISK. FOR NOW, I PUT POSSIBLE SEVERE WORDING WITH MODERATE RAIN IN THE PRECIP TYPE, AND PLAN TO GO STRONG ON HEAVY RAIN AND LARGE HAIL IN THE HWO, WITH THE RISK OF AN ISOLATED TORNADO NOT OUT OF THE QUESTION. AS FOR POPS, I UPPED THE POPS IN OUR NORTHEAST TO 40 PERCENT, AND THAT MAY NEED TO BE HEIGHTENED EVEN MORE ONCE AND WHERE THE PRECIP FIRES. OF OTHER CONCERNS, THERE IS A 50 TO 60 KT JET AT 850MB WHICH WILL HAVE LITTLE TROUBLE MIXING DOWN AS THE DAY WARMS UP, SO THE WIND ADVISORY WAS EXPANDED TO INCLUDE ALL OUR COUNTIES, FROM ELKHART TO MEDICINE LODGE AND FROM INGLEWOOD TO HAYS. WINDS WILL BE SOUTH AND INCREASE TOWARDS 17Z INTO THE 30G40 MPH RANGE, FIRST IN THE WEST NEAR THE COLORADO BORDER AND THEN QUICKLY SPREAD TO THE EAST TOWARDS HAYS, PRATT AND KIOWA. WINDS MAY INCREASE STILL MORE DURING THE AFTERNOON HOURS. ICT AND PUB BOTH MADE GOOD POINTS THAT THE ADVISORY (WARNING LEVEL IN PUB`S AREA) COULD EXTEND INTO THE EARLY EVENING. I CHOSE THE END TIME FOR THE WIND ADVISORY AS 02Z, CLOSER TO THE TIME OF SUNDOWN THAN THE 04Z END TIME CHOSEN BY PUB. IT WILL BE HOT AGAIN TODAY, AND HAVE TO WONDER IF ANY SPOTS IN MY FORECAST AREA WILL REACH THE 100F DEGREE MARK. STAYED JUST SHY OF THAT AND THIS IS NEAR ISC MAX TEMPS. I, WENT WITH HIGHS FROM THE MID 90S IN OUR EAST AT SUCH LOCATIONS OF MEDICINE LODGE AND LARNED, AND RANGING UP TO THE UPPER 90S IN OUR WEST NEAR GARDEN CITY AND JOHNSON CITY. THE POPS DECREASED TO 20 PERCENT THIS EVENING, BUT WILL EXIST THROUGH ABOUT 06Z, AS THE DRY LINE (OR WARM FRONT) RECEDES WEST TO NEAR EASTERN COLORADO. WINDS WILL ONLY DECREASE INTO THE 20 TO 25 MPH RANGE, WITH THE GRADIENT STILL TIGHT FROM COLORADO TO CENTRAL KANSAS. THESE WINDS WILL ASSIST IN KEEPING TEMPERATURES FROM FALLING FAST, AND MINIMUM TEMPERATURES SHOULD RANGE FROM THE LOWER TO MID 60S NEAR THE COLORADO BORDER TO THE LOWER 70S FROM HAYS TO SAINT JOHN TO MEDICINE LODGE. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 222 PM CDT FRI MAY 25 2012 SATURDAY NIGHT: THE 12Z NAM SHOWS A WEAK UL SPEED MAX MOVING ACROSS WESTERN KANSAS SATURDAY NIGHT. THIS MIGHT BE ENOUGH TO TRIGGER ISOLATED CONVECTION ACROSS THE CENTRAL OR WESTERN ZONES TOMORROW EVENING. NOT VERY CONFIDENT ON THE OVERALL COVERAGE GIVEN THIS SMALL PERTURBATION THAT MIGHT NOT PAN OUT AND FAIRLY WARM 11 TO 12 DEG C 700 HPA TEMPERATURES. AS A RESULT, WE KEEP POPS IN THE SLIGHT CHANCE CATEGORY. KINEMATIC AND THERMODYNAMIC PROFILES ARE NOT THAT IMPRESSIVE FOR SEVERE (1000 J/KG SBCAPE/20 KT 0-6 KM SHEAR). SUNDAY: THE FORECAST BECOMES MUCH MORE INTERESTING SUNDAY AFTERNOON AND EVENING. A 95 KT 250 HPA JET WILL MOVE ACROSS NORTHEAST COLORADO AND INTO WESTERN NEBRASKA WHICH WILL PUT THE AREA IN A MORE FAVORABLE DIFFLUENT PATTERN ALOFT TO SUPPORT CONVECTION. THE HIGHEST POPS ARE EXPECTED ALONG THE TRIPLE POINT OF THE SURFACE LOW PRESSURE CENTER, THE DRYLINE AND THE WARM FRONT. SEVERE WEATHER WILL DEFINITELY BE MORE OF A CONCERN AS THE OVERALL KINEMATIC PROFILE STRENGTHENS AND IN COMBINATION WITH DECENT SURFACE BASED CAPE. ANVIL LEVEL SR FLOW AROUND 35 KT, 3 TO 6 KM SR FLOW OF 18 KT, 700-850 HPA LAPSE RATES OF 8.2 C/KM, AND 500-300 HPA LAPSE RATES OF 7.2 C/KM ALL POINT TO THE CHANCE FOR GIANT HAIL SUNDAY. MUCAPE/MLCAPE DURING THE AFTERNOON IS FORECAST TO ABOUT AROUND 2000 J/KG. THE EVENT LOOKS SYNOPTICALLY SIMILAR TO JUNE 18TH 2010 WHERE GRAPEFRUIT SIZE HAIL WAS REPORTED. OF COURSE, THIS IS ALL MESOSCALE NOISE AT THIS POINT AND SUBJECT TO CHANGE. FOR TORNADO POTENTIAL, WOULD NOT RULE OUT A TORNADO BUT THE LOWER LCLS ARE FORECAST ACROSS NC KS/SC NE ALONG THE WARM FRONT. MONDAY: 250/500 HPA FLOW BECOMES MORE WESTERLY IN THE WAKE OF THE DEPARTING SYNOPTIC WAVE MONDAY. WILL CONTINUE WITH A DRY FORECAST AND SLIGHTLY ABOVE NORMAL HIGHS. HAVE GONE WITH THE WARMER ECMWF SOLUTION GIVEN 850 HPA TEMPERATURES STILL FORECAST IN THE 20S DEG C. A MUCH DRIER AIRMASS WILL ADVECT IN ACROSS THE REGION WITH DEWPOINTS TANKING DOWN INTO THE 30S & 40S DEG F. TUESDAY AND BEYOND: DID NOT STRAY FROM THE ALLBLEND POPS FOR TUESDAY AND WEDNESDAY. A WEAK SUBTROPIC JET WILL MOVE ACROSS THE SOUTHWEST WITH LEE TROUGHING, MOISTURE RETURN, AND THE POSSIBILITY OF THUNDERSTORMS MIDWEEK. THE ECMWF IS MORE CONSERVATIVE WITH QPF THAN COMPARED TO THE GFS SO CONFIDENCE IS LOW. TEMPERATURES MAY FINALLY COOL DOWN TO NEAR NORMAL VALUES TOWARDS THE END OF THE MONTH AS NORTHWESTERLY FLOW ALOFT DEVELOPS AND 700/850 HPA TEMPERATURES COOL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1226 AM CDT SAT MAY 26 2012 OVERALL, CONDITIONS WILL BE VFR WITH STRONG WINDS SATURDAY. AS A WARM FRONT TO THE NORTH CONTINUES TO MARCH NORTHEASTWARD OVERNIGHT AND SATURDAY, CIRRUS CLOUD AND SOUTHWEST WINDS AT 12G25 KNOTS WILL CONTINUE OVERNIGHT. SOME FOG AS FORMED IN PARTS OF WYOMING AND NORTHERN COLORADO, AND THIS IFR/MVFR FOG MAY SLIP SOUTH LATE TONIGHT AND BRING VSBYS DOWN IN HYS AND GCK TO THE IFR CATEGORY. THESE CONDITIONS WILL IMPROVE BY 13Z, AS A DRY LINE FORMS ACROSS SOUTHWEST KANSAS SATURDAY AND A LOW PRESSURE TROUGH DEEPENS IN THE LEE OF THE ROCKIES. WINDS WILL BE SOUTH SATURDAY AT 26G36 KNOTS. IN ADDITION TO THE WIND, BY LATE IN THE AFTERNOON, THERE IS A CHANCE FOR STRONG STORMS IN THE HYS AND GCK TAF SITES, AND A SLIGHT CHANCE IN THE DDC TAF SITE. I CHOSE TO LEAVE MENTION OF TS OUT OF THE TAFS, SINCE THAT IS 15 HOURS OR SO OUT IN THE TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 96 70 92 62 / 30 20 70 30 GCK 97 69 93 59 / 30 30 30 20 EHA 96 62 90 58 / 20 30 20 10 LBL 96 65 91 60 / 30 20 30 10 HYS 97 72 91 63 / 40 30 80 70 P28 94 72 91 67 / 10 20 70 30 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 9 PM CDT /8 PM MDT/ THIS EVENING FOR KSZ030-031-043>046-061>066-074>081-084>090. && $$ SYNOPSIS...BURGERT SHORT TERM...BURKE LONG TERM...SUGDEN AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1236 AM CDT SAT MAY 26 2012 ...UPDATED FOR THE 06Z TAF ISSUANCE... .SYNOPSIS... ISSUED AT 1215 PM CDT FRI MAY 25 2012 A -27C 500MB UPPER LOW WAS LOCATED OVER NORTHERN CALIFORNIA WITH A SOUTHWEST FLOW PRESENT FROM THE SOUTHWESTERN UNITED STATES ACROSS THE CENTRAL AND NORTHERN PLAINS. A SUBTLE UPPER LEVEL DISTURBANCE WERE EMBEDDED IN THIS SOUTHWEST FLOW WITH ONE SUBTLE WAVE APPEARING ACROSS THE TEXAS PANHANDLE, VIA WATER VAPOR LOOP. AT 250 AND 300MB LEVEL AN UPPER LEVEL JET STREAK WAS LOCATED ACROSS THE NORTHERN PLAINS WITH THE LEFT ENTRANCE REGION OF THIS JET NEAR CENTRAL/EASTERN NEBRASKA. AT 700MB THE NORTHERN EDGE OF ELEVATED MIXED LAYER APPEARS TO EXTEND FROM WEST TO EAST ACROSS NORTHERN KANSAS WITH +12C AT DOGE CITY, +14C AT AMARILLO, AND +13C AT OKLAHOMA CITY. AT 850MB LEVEL MOISTURE WAS POOLING NEAR THE NORTHERN EDGE OF THE 850MB WARM FRONT WHICH STRETCHED FROM THE PANHANDLE OF OKLAHOMA INTO SOUTH CENTRAL KANSAS. THE WARM FRONT WHICH WAS LOCATED NEAR THE OKLAHOMA BORDER AT 12Z FRIDAY WAS AT 17Z LOCATED FROM NEAR GARDEN CITY EASTWARD INTO CENTRAL KANSAS. A DRYLINE APPEARS TO BE DEVELOPING JUST WEST OF DODGE CITY SOUTH OF THIS WARM FRONT. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 246 PM CDT FRI MAY 25 2012 DODGE CITY RADAR APPEARS TO BE PICKING UP ON THE WARM FRONT AS OF 18Z AND PLACED THIS BOUNDARY FROM NEAR GARDEN CITY TO JETMORE TO NEAR BURDETT AND LARNED. RAP ALSO INDICATING IMPROVING 925-850MB FRONTOGENESIS ALONG THIS BOUNDARY WHILE 700MB TEMPERATURES VARIED FROM +13 TO +14C. SPC MESOSCALE ANALYSIS PAGE STILL INDICATING A CAP IN PLACE BUT ALSO HAD 2000-3000J/KG PRESENT IN THIS AREA AS WELL. CLOUD COVER FINALLY STARTING TO ERODE AND TEMPERATURES ARE STARTING TO CLIMB INTO THE MID TO UPPER 80S. AT THIS TIME IT STILL APPEARS THAT THE CONVECTIVE TEMPERATURE WILL BE REACHED BY LATE DAY...ESPECIALLY EAST OF JETMORE. WILL THEREFORE RAISE PRECIPITATION CHANCES NEAR THIS BOUNDARY AND EAST OF JETMORE LATE TODAY. LATEST RAP CONTINUES TO INDICATED 0-6KM SHEAR OF 50KTS, LOW LEVEL SHEAR NEAR/NORTH OF THE WARM FRONT AND LOW LCLS AT 00Z SATURDAY SO IF STORMS CAN OVERCOME THE CAP LARGE HAIL AND POSSIBLY A TORNADO OR TWO STILL SEEMS REASONABLE NEAR THE WARM FRONT. CORFIDI VECTORS AND BUNKERS STORM MOTION INDICATES A NORTHEAST MOVEMENT FROM THESE STORMS LATE TODAY WHICH SHOULD TAKE ANY LATE DAY CONVECTION ALONG THIS BOUNDARY EAST OF HIGHWAY 281 BY OR SHORTLY AFTER SUNSET. A DRYLINE THIS AFTERNOON WILL EXTEND SOUTH OF THIS WARM FRONT INTO THE PANHANDLE OF OKLAHOMA. BASED ON 18Z SURFACE ANALYSIS THIS DRYLINE LOCATED NEAR DODGE CITY AND ASHLAND. THIS WILL ALSO BE AN AREA OF FORCING LATE TODAY BUT AT THIS TIME IT APPEARS THAT GIVEN THE HIGHER LCLS AND WEAKER LOW LEVEL SHEAR THE PRIMARY HAZARD FROM THESE STORMS IF THEY DEVELOP WILL BE HAIL. AGAIN STORM MOTION WILL TAKE THESE STORMS NORTHEAST AT 30 TO 40 KNOTS. AFTER MIDNIGHT THE WARM FRONT IS STILL FORECAST BY ALL THE MODELS TO LIFT NORTH OF INTERSTATE 70 AS THE DRY LINE RETREATS WESTWARD TOWARDS THE COLORADO BORDER. AN AREA OF LOW PRESSURE WILL BEGIN TO DEVELOP ALONG THE LEE OF THE ROCKIES ON SATURDAY AS THE NORTHERN CALIFORNIA UPPER LOW STARTS TO MOVE EAST ACROSS THE WESTERN UNITED STATES. FALLING PRESSURES ALONG THE LEE TROUGH WILL RESULT IN A TIGHT SURFACE PRESSURE GRADIENT ACROSS WESTERN KANSAS DURING THE DAY. THIS ALONG WITH MEAN MIXED LAYER WINDS OF OF 35 TO NEAR 40 KTS AM LEANING TOWARDS ISSUING A WIND ADVISORY FOR PORTIONS OF OF WESTERN KANSAS. PREVIOUS FORECAST WITH SUSTAINED WINDS OF 27 TO NEAR 30 KNOTS STILL APPEARS ON TRACK. THERE WILL ALSO BE A SLIGHT CHANCE FOR THUNDERSTORMS ONCE AGAIN NEAR A SURFACE BOUNDARY WHICH AT THIS TIME APPEARS TO EXTEND FROM NEAR HAYS TO ELKHART LATE DAY. THIS IS SLIGHTLY FURTHER WEST THAN WHAT PREVIOUS MODELS HAD PLACED THIS BOUNDARY LATE DAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 222 PM CDT FRI MAY 25 2012 SATURDAY NIGHT: THE 12Z NAM SHOWS A WEAK UL SPEED MAX MOVING ACROSS WESTERN KANSAS SATURDAY NIGHT. THIS MIGHT BE ENOUGH TO TRIGGER ISOLATED CONVECTION ACROSS THE CENTRAL OR WESTERN ZONES TOMORROW EVENING. NOT VERY CONFIDENT ON THE OVERALL COVERAGE GIVEN THIS SMALL PERTURBATION THAT MIGHT NOT PAN OUT AND FAIRLY WARM 11 TO 12 DEG C 700 HPA TEMPERATURES. AS A RESULT, WE KEEP POPS IN THE SLIGHT CHANCE CATEGORY. KINEMATIC AND THERMODYNAMIC PROFILES ARE NOT THAT IMPRESSIVE FOR SEVERE (1000 J/KG SBCAPE/20 KT 0-6 KM SHEAR). SUNDAY: THE FORECAST BECOMES MUCH MORE INTERESTING SUNDAY AFTERNOON AND EVENING. A 95 KT 250 HPA JET WILL MOVE ACROSS NORTHEAST COLORADO AND INTO WESTERN NEBRASKA WHICH WILL PUT THE AREA IN A MORE FAVORABLE DIFFLUENT PATTERN ALOFT TO SUPPORT CONVECTION. THE HIGHEST POPS ARE EXPECTED ALONG THE TRIPLE POINT OF THE SURFACE LOW PRESSURE CENTER, THE DRYLINE AND THE WARM FRONT. SEVERE WEATHER WILL DEFINITELY BE MORE OF A CONCERN AS THE OVERALL KINEMATIC PROFILE STRENGTHENS AND IN COMBINATION WITH DECENT SURFACE BASED CAPE. ANVIL LEVEL SR FLOW AROUND 35 KT, 3 TO 6 KM SR FLOW OF 18 KT, 700-850 HPA LAPSE RATES OF 8.2 C/KM, AND 500-300 HPA LAPSE RATES OF 7.2 C/KM ALL POINT TO THE CHANCE FOR GIANT HAIL SUNDAY. MUCAPE/MLCAPE DURING THE AFTERNOON IS FORECAST TO ABOUT AROUND 2000 J/KG. THE EVENT LOOKS SYNOPTICALLY SIMILAR TO JUNE 18TH 2010 WHERE GRAPEFRUIT SIZE HAIL WAS REPORTED. OF COURSE, THIS IS ALL MESOSCALE NOISE AT THIS POINT AND SUBJECT TO CHANGE. FOR TORNADO POTENTIAL, WOULD NOT RULE OUT A TORNADO BUT THE LOWER LCLS ARE FORECAST ACROSS NC KS/SC NE ALONG THE WARM FRONT. MONDAY: 250/500 HPA FLOW BECOMES MORE WESTERLY IN THE WAKE OF THE DEPARTING SYNOPTIC WAVE MONDAY. WILL CONTINUE WITH A DRY FORECAST AND SLIGHTLY ABOVE NORMAL HIGHS. HAVE GONE WITH THE WARMER ECMWF SOLUTION GIVEN 850 HPA TEMPERATURES STILL FORECAST IN THE 20S DEG C. A MUCH DRIER AIRMASS WILL ADVECT IN ACROSS THE REGION WITH DEWPOINTS TANKING DOWN INTO THE 30S & 40S DEG F. TUESDAY AND BEYOND: DID NOT STRAY FROM THE ALLBLEND POPS FOR TUESDAY AND WEDNESDAY. A WEAK SUBTROPIC JET WILL MOVE ACROSS THE SOUTHWEST WITH LEE TROUGHING, MOISTURE RETURN, AND THE POSSIBILITY OF THUNDERSTORMS MIDWEEK. THE ECMWF IS MORE CONSERVATIVE WITH QPF THAN COMPARED TO THE GFS SO CONFIDENCE IS LOW. TEMPERATURES MAY FINALLY COOL DOWN TO NEAR NORMAL VALUES TOWARDS THE END OF THE MONTH AS NORTHWESTERLY FLOW ALOFT DEVELOPS AND 700/850 HPA TEMPERATURES COOL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1226 AM CDT SAT MAY 26 2012 OVERALL, CONDITIONS WILL BE VFR WITH STRONG WINDS SATURDAY. AS A WARM FRONT TO THE NORTH CONTINUES TO MARCH NORTHEASTWARD OVERNIGHT AND SATURDAY, CIRRUS CLOUD AND SOUTHWEST WINDS AT 12G25 KNOTS WILL CONTINUE OVERNIGHT. SOME FOG AS FORMED IN PARTS OF WYOMING AND NORTHERN COLORADO, AND THIS IFR/MVFR FOG MAY SLIP SOUTH LATE TONIGHT AND BRING VSBYS DOWN IN HYS AND GCK TO THE IFR CATEGORY. THESE CONDITIONS WILL IMPROVE BY 13Z, AS A DRY LINE FORMS ACROSS SOUTHWEST KANSAS SATURDAY AND A LOW PRESSURE TROUGH DEEPENS IN THE LEE OF THE ROCKIES. WINDS WILL BE SOUTH SATURDAY AT 26G36 KNOTS. IN ADDITION TO THE WIND, BY LATE IN THE AFTERNOON, THERE IS A CHANCE FOR STRONG STORMS IN THE HYS AND GCK TAF SITES, AND A SLIGHT CHANCE IN THE DDC TAF SITE. I CHOSE TO LEAVE MENTION OF TS OUT OF THE TAFS, SINCE THAT IS 15 HOURS OR SO OUT IN THE TAF PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 70 92 62 86 / 20 40 30 0 GCK 69 93 59 85 / 20 30 20 0 EHA 66 90 58 85 / 20 10 10 0 LBL 69 91 60 86 / 20 20 20 0 HYS 72 91 63 84 / 20 60 70 0 P28 72 91 67 89 / 10 30 30 10 && .DDC WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 8 PM CDT /7 PM MDT/ THIS EVENING FOR KSZ043-044-061>063-074>077-084>087. && $$ SYNOPSIS...BURGERT SHORT TERM...BURGERT LONG TERM...SUGDEN AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1025 PM EDT SUN MAY 27 2012 .SYNOPSIS... HIGH PRESSURE WILL REMAIN WELL OFF THE NORTH CAROLINA COAST THROUGH MONDAY...AS TROPICAL SYSTEM BERYL SLOWLY DRIFTS WEST TOWARDS THE COAST OF NORTHERN FLORIDA. AN APPROACHING COLD FRONT IS EXPECTED TO PULL BERYL UP THE SOUTHEAST COAST BY MID WEEK...BRINGING UNSETTLED CONDITIONS TO THE MID ATLANTIC AND CAROLINAS. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... THE MAIN FEATURE THIS EVENING WAS A RATHER IMPRESSIVE MCS THAT MOVED S TOWARD THE DC AND BALTIMORE METRO AREAS BEFORE WEAKENING. AT THIS TIME THERE STILL APPEARS TO BE A CHANCE OF SHOWERS AND THUNDERSTORMS IN THE EXTREME NORTHERN PORTION OF THE REGION FROM THE NORTHERN NECK TO THE WESTERN PORTION OF THE LOWER MD EASTERN SHORE. THE LAST FEW RUNS OF THE HRRR HAVE HANDLED THE CONVECTIVE SYSTEM FAIRLY WELL ONCE IT INITIALIZED IT...ALTHOUGH IT HAS BEEN A FEW HOURS SLOW. THE HRRR ALSO SUGGEST THE LINE BUILDING SOME TO THE WEST...SO A CHANCE WILL BE MAINTAINED WESTWARD TO LOUISA COUNTY. ANY ACTIVITY SHOULD DIMINISH AFTER 06Z. IN GENERAL THE MCS GENERATED ALONG A FRONTAL BOUNDARY ACROSS PA AND LOCALLY ENHANCE MID/UPPER LEVEL NW FLOW...AND THEN FOLLOWED MOIST LOW-LEVEL AIRSTREAMS ORIGINATING FROM THE ATLANTIC AND OHIO VALLEY. THIS WAS DERIVED BY ANALYZING AREA RADAR VWP DATA. STRATUS IS STILL FAVORED OVER FOG TONIGHT AS THE AIRMASS IS MORE TROPICAL AND WITH LINGERING CLOUD COVER ASSOCIATED WITH THE MCS. LOW TEMPERATURES SHOULD BE ABOUT 3-5F WARMER THAN LAST NIGHT WITH READINGS RANGING FROM 65-70. OF NOTE...THE LATEST WX ANALYSIS DEPICTS TROPICAL STORM BERYL OFF THE COAST OF NRN FL COAST (SEE LATEST FORECAST AT WWW.NHC.NOAA.GOV FOR FURTHER DETAILS). && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... LIGHT STEERING FLOW KEEPS SUBTROPICAL STORM BERYL OVER THE SOUTHEAST U.S. THROUGH TUESDAY. MEANWHILE...AN UPPER LOW CURRENTLY OVER MONTANA TRACKS TO HUDSON BAY CANADA BY TUESDAY. THIS SYSTEM WILL EVENTUALLY BRING THE APPROACH OF A COLD FRONT ACROSS THE MID ATLANTIC REGION ON WEDNESDAY AND PROVIDE JUST ENOUGH FORCE TO MOVE BERYL UP THE SOUTHEAST AND SOUTHERN MID ATLANTIC COAST WEDNESDAY. MONDAY...THE UPPER LEVEL RIDGE AXIS WEAKENS SLIGHTLY AND LOW LEVEL FLOW TURNS MORE TO THE S RATHER THAN E/SE OF THE PAST SEVERAL DAYS. WITH SLIGHTLY LOWER HEIGHTS ALOFT AS THE UPPER RIDGE BREAKS DOWN MAY SEE AFTERNOON SHOWERS AND THUNDERSTORMS MOVE A BIT FARTHER NORTH INTO VA BY AFTN...ALTHOUGH WILL STILL ONLY CARRY 20-30% POPS. HIGHS GENLY 85-90. TUE/WED...THE INTERACTION BETWEEN THE APPROACHING COLD FRONT AND BERYL MOVING UP THE MID ATLANTIC COAST WILL INCREASE PRECIPITATION CHANCES BY LATE IN THE THE DAY...ESPECIALLY OVER THE INTERIOR. CONVECTIVE PARAMETERS ARE FAVORABLE FOR THUNDERSTORMS TO DEVELOP W/ HVY RAIN THE MAIN CONCERN AS PWATS APPROACH 2 INCHES...W/ LITTLE SHEAR DO NOT ANTICIPATE MUCH MORE THAN ISOLATED STRONG STORMS IN TERMS OF WIND. SHOWERS AND STORMS ARE EXPECTED TO BECOME MORE WIDESPREAD AS DEEPER MSTR MOVES IN FROM THE SSW. PERSIST THROUGH MIDDAY WED AS THE COLD FRONT PUSHES ACROSS THE REGION. HAVE HI CHC POPS FAR W TO LIKELY ELSEWHERE ON WED. TEMPS HELD DOWN SOMEWHAT W/ CLOUDS...HIGHS LWR-MID 80S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... FOLLOWED HPC`S LEAD FOR FRONTAL POSITIONS AND PRESSURE SYSTEMS. THE THURSDAY THROUGH SUNDAY PERIOD WILL BEGIN WITH A COLD FRONT PUSHING OFF THE COAST WEDNESDAY NIGHT ASSURING THAT BERYL WILL STAY WELL OFFSHORE IN ITS NORTHEASTWARD TREK. THE FRONT WILL THEN STALL JUST TO OUR SOUTH AS LOW PRESSURE MOVES FROM THE SOUTHERN PLAINS THROUGH THE OHIO VALLEY TO THE NORTHEASTERN STATES...PULLING THE FRONT BACK TO THE NORTH FRIDAY. MODELS ARE FAIRLY CONSISTENT WITH BRINGING AN UPPER LEVEL TROUGH TO THE AREA NEXT WEEKEND. HAVE MOST OF THE PCPN DURING THIS PERIOD OCCURRING WITH THE PASSAGE OF THE LOW AROUND FRIDAY WITH PCPN DIMINISHING SATURDAY ON NW SURFACE FLOW (BEHIND A COLD FRONTAL PASSAGE EARLY SATURDAY). THIS WOULD RESULT IN A WEEKEND OF MAINLY DRY CONDITIONS WITH PLEASANT TEMPERATURES. TEMPERATURES START OFF FAIRLY WARM THURSDAY WITH HIGHS IN THE MID TO UPPER 80S WELL INLAND AND NEAR 80 TO THE LOWER 80S NEAR THE COAST AND OVER THE LOWER EASTERN SHORE. CLOUDS AND PCPN RESULT IN TEMPERATURES HOLDING IN THE UPPER 70S TO LOWER 80S FRIDAY. HIGHS ARE FORECAST TO BE IN THE MID 70S TO LOWER 80S OVER THE WEEKEND. LOWS WILL BE FROM 60 TO 65 INLAND AND MAINLY MID TO UPR 60S NEAR THE && .AVIATION /02Z MONDAY THROUGH FRIDAY/... AS OF 00Z MON...A LINE OF STRONG THUNDERSTORMS IS QUICKLY MOVING SOUTH FROM PA/MD. KRIC AND KSBY MAY BE IMPACTED BY STRONG WINDS AND HEAVY RAIN AROUND 04Z MON IF THIS LINE HOLDS TOGETHER. SHORT RANGE MODELS DO SHOW SOME ACTIVITY IN THOSE AREAS BUT IT NOT NEARLY AS STRONG AS THE LINE IS CURRENTLY. EXPECT ANOTHER ROUND OF IFR/LIFR FLIGHT RESTRICTIONS AT KRIC...KSBY AND KPHF MON MORNING...WITH MVFR POSSIBLE AT KORF AND KECG. CONDITIONS SHOULD BECOME VFR AT ALL SITES BY 13Z MON. A SCT CU DECK WILL PREVAIL WITH VERY ISOLATED SHOWERS ARE POSSIBLE MON AFTERNOON. PRECIP CHANCES WILL CONTINUE TO INCREASE TUE INTO WED AS A COLD FRONT APPROACHES THE FORECAST AREA FROM THE WEST. && .MARINE... NO HEADLINES ARE IN EFFECT WITH THIS ISSUANCE. SE TO S WINDS SHOULD HOLD JUST BELOW SCA CRITERIA OVER THE BAY. SEAS ARE JUST BELOW 5 FT IN THE NORTH CAROLINA COASTAL WATERS AND WAVEWATCH HAS THOSE SEAS DIMINISHING THROUGH THE EVENING AND OVERNIGHT HOURS. SOUTH WINDS INCREASE TOWARD MID WEEK AS A COLD FRONT APPROACHES FROM THE WEST. SCA CONDITIONS MAY DEVELOP IN PORTIONS OF THE AREA LATE TUESDAY OR WEDNESDAY. THE WIND FIELD WILL BE IMPACTED BY THE PROXIMITY OF TROPICAL SYSTEM (OR REMNANTS) BERYL LATE WEDNESDAY AND WEDNESDAY NIGHT...RESULTING IN DECREASING SOUTHERLY WINDS. WINDS THEN TURN TO NW/N BEHIND A COLD FRONT THURSDAY MORNING. IT NOW APPEARS THAT THE CONDITIONS BEHIND THE FRONT WILL REMAIN BELOW SCA. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...LKB NEAR TERM...AJZ/LKB SHORT TERM...LKB LONG TERM...LSA AVIATION...DAP MARINE...LSA
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
857 PM EDT SUN MAY 27 2012 .SYNOPSIS... HIGH PRESSURE WILL REMAIN WELL OFF THE NORTH CAROLINA COAST THROUGH MONDAY...AS TROPICAL SYSTEM BERYL SLOWLY DRIFTS WEST TOWARDS THE COAST OF NORTHERN FLORIDA. AN APPROACHING COLD FRONT IS EXPECTED TO PULL BERYL UP THE SOUTHEAST COAST BY MID WEEK...BRINGING UNSETTLED CONDITIONS TO THE MID ATLANTIC AND CAROLINAS. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... THE MAIN FEATURE THIS EVENING IS A RATHER IMPRESSIVE MCS MOVING S ACROSS THE DC AND BALTIMORE METRO AREAS. CURRENT TIMING PER RADAR MOSAIC LOOP WOULD BRING IT INTO NORTHERN PORTIONS OF THE AREA JUST AFTER 10 PM. THERE IS NOT A REAL CLEAR INDICATOR OF ITS DRIVING FORCE. HOWEVER...AN EXAMINATION OF THE WIND FIELD PER LWX/CCX/DIX VWP DATA SEEM TO REVEAL SOUTHERLY FLOW BELOW 2K FT AND SW FLOW AROUND 3-4K FT COMBINING WITH ENHANCE MID AND UPPER LEVEL NW FLOW IN THE WAKE OF THE MCS. WITH RESPECT TO THE TRACK...IT APPEARS TO BE FOLLOWING A N-S ORIENTED AXIS OF ~1500 J/KG OF MLCAPE. AT THIS POINT CONFIDENCE IS GROWING THAT IT WILL REACH THE NORTHERN PORTION OF THE AREA AROUND THE AFOREMENTIONED TIME. HOWEVER...THERE IS STILL LIMITED CONFIDENCE IN ITS STRENGTH. PREVIOUS DISCUSSION... LATEST WX ANALYSIS DEPICTS TROPICAL STORM BERYL OFF THE COAST OF NRN FL COAST (SEE LATEST FORECAST AT WWW.NHC.NOAA.GOV FOR FURTHER DETAILS). CLOSER TO HOME...MOSTLY CLOUDY SKIES AND ISOLATED TO SCATTERED SHOWERS PERSIST ACRS NE NC/FAR SOUTHERN VA IN THE WARM/HUMID AIRMASS. SKIES ARE SOMEWHAT LESS CLOUDY FARTHER N/W...WHERE TEMPS ARE GENLY IN THE MID-UPR 80S (80-85 FARTHER SE). MUCH OF THE PRECIP ACTIVITY APPEARS TO BE STRUGGLING TO MAINTAIN ITSELF AS IT MOVES INTO VA...AND BULK OF IT REMAINS OFF TO OUR SW...SO WILL CARRY ONLY LOW CHC POPS FROM ABOUT ECG TO AVC AND SW...WITH A 20% POP OVER SRN VA THRU 8 PM. MODELS W/ BEST HANDLE ON CURRENT CONDITIONS..THE RAP AND HRRR SHOW THIS ACTIVITY DIMINISHING AFTER SUNSET AND HAVE DROPPED POPS THEREAFTER. ONLY CONCERN WOULD BE IF MCS ACTIVITY OVER SOUTH CENTRAL PA/WV WERE TO HOLD TOGETHER AND REACH AKQ CWA DURING THE LATE EVENING HRS. GIVEN FAIRLY WEAK FLOW ALOFT (NW FLOW GENLY STAYING TO OUR N) DOUBT THIS CONVECTION WILL MAKE IT INTO THE CWA ALTHOUGH WILL NEED TO MONITOR CLOSELY. VARIABLY CLOUDY SKIES OVERALL THROUGH THE EVENING/OVERNIGHT...W/ INCREASING CLOUDS LIKELY JUST PRIOR TO DAYBREAK. DECIDED NOT TO INCLUDE FOG IN FCST AS AIRMASS IS SOMEWHAT MORE TROPICAL IN NATURE THAN PAST SEVERAL NIGHTS (PROBABLY MORE OF A STRATUS SETUP RATHER THAN FOG) MODELS SUGGEST A LGT S WIND OVERNIGHT...KEEPING MIN TEMPS ABOUT 3-5 F WARMER THAN PAST FEW NIGHTS...WITH LOWS MAINLY IN THE 65-70 RANGE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... LIGHT STEERING FLOW KEEPS SUBTROPICAL STORM BERYL OVER THE SOUTHEAST U.S. THROUGH TUESDAY. MEANWHILE...AN UPPER LOW CURRENTLY OVER MONTANA TRACKS TO HUDSON BAY CANADA BY TUESDAY. THIS SYSTEM WILL EVENTUALLY BRING THE APPROACH OF A COLD FRONT ACROSS THE MID ATLANTIC REGION ON WEDNESDAY AND PROVIDE JUST ENOUGH FORCE TO MOVE BERYL UP THE SOUTHEAST AND SOUTHERN MID ATLANTIC COAST WEDNESDAY. MONDAY...THE UPPER LEVEL RIDGE AXIS WEAKENS SLIGHTLY AND LOW LEVEL FLOW TURNS MORE TO THE S RATHER THAN E/SE OF THE PAST SEVERAL DAYS. WITH SLIGHTLY LOWER HEIGHTS ALOFT AS THE UPPER RIDGE BREAKS DOWN MAY SEE AFTERNOON SHOWERS AND THUNDERSTORMS MOVE A BIT FARTHER NORTH INTO VA BY AFTN...ALTHOUGH WILL STILL ONLY CARRY 20-30% POPS. HIGHS GENLY 85-90. TUE/WED...THE INTERACTION BETWEEN THE APPROACHING COLD FRONT AND BERYL MOVING UP THE MID ATLANTIC COAST WILL INCREASE PRECIPITATION CHANCES BY LATE IN THE THE DAY...ESPECIALLY OVER THE INTERIOR. CONVECTIVE PARAMETERS ARE FAVORABLE FOR THUNDERSTORMS TO DEVELOP W/ HVY RAIN THE MAIN CONCERN AS PWATS APPROACH 2 INCHES...W/ LITTLE SHEAR DO NOT ANTICIPATE MUCH MORE THAN ISOLATED STRONG STORMS IN TERMS OF WIND. SHOWERS AND STORMS ARE EXPECTED TO BECOME MORE WIDESPREAD AS DEEPER MSTR MOVES IN FROM THE SSW. PERSIST THROUGH MIDDAY WED AS THE COLD FRONT PUSHES ACROSS THE REGION. HAVE HI CHC POPS FAR W TO LIKELY ELSEWHERE ON WED. TEMPS HELD DOWN SOMEWHAT W/ CLOUDS...HIGHS LWR-MID 80S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... FOLLOWED HPC`S LEAD FOR FRONTAL POSITIONS AND PRESSURE SYSTEMS. THE THURSDAY THROUGH SUNDAY PERIOD WILL BEGIN WITH A COLD FRONT PUSHING OFF THE COAST WEDNESDAY NIGHT ASSURING THAT BERYL WILL STAY WELL OFFSHORE IN ITS NORTHEASTWARD TREK. THE FRONT WILL THEN STALL JUST TO OUR SOUTH AS LOW PRESSURE MOVES FROM THE SOUTHERN PLAINS THROUGH THE OHIO VALLEY TO THE NORTHEASTERN STATES...PULLING THE FRONT BACK TO THE NORTH FRIDAY. MODELS ARE FAIRLY CONSISTENT WITH BRINGING AN UPPER LEVEL TROUGH TO THE AREA NEXT WEEKEND. HAVE MOST OF THE PCPN DURING THIS PERIOD OCCURRING WITH THE PASSAGE OF THE LOW AROUND FRIDAY WITH PCPN DIMINISHING SATURDAY ON NW SURFACE FLOW (BEHIND A COLD FRONTAL PASSAGE EARLY SATURDAY). THIS WOULD RESULT IN A WEEKEND OF MAINLY DRY CONDITIONS WITH PLEASANT TEMPERATURES. TEMPERATURES START OFF FAIRLY WARM THURSDAY WITH HIGHS IN THE MID TO UPPER 80S WELL INLAND AND NEAR 80 TO THE LOWER 80S NEAR THE COAST AND OVER THE LOWER EASTERN SHORE. CLOUDS AND PCPN RESULT IN TEMPERATURES HOLDING IN THE UPPER 70S TO LOWER 80S FRIDAY. HIGHS ARE FORECAST TO BE IN THE MID 70S TO LOWER 80S OVER THE WEEKEND. LOWS WILL BE FROM 60 TO 65 INLAND AND MAINLY MID TO UPR 60S NEAR THE && .AVIATION /01Z MONDAY THROUGH FRIDAY/... AS OF 00Z MON...A LINE OF STRONG THUNDERSTORMS IS QUICKLY MOVING SOUTH FROM PA/MD. KRIC AND KSBY MAY BE IMPACTED BY STRONG WINDS AND HEAVY RAIN AROUND 04Z MON IF THIS LINE HOLDS TOGETHER. SHORT RANGE MODELS DO SHOW SOME ACTIVITY IN THOSE AREAS BUT IT NOT NEARLY AS STRONG AS THE LINE IS CURRENTLY. EXPECT ANOTHER ROUND OF IFR/LIFR FLIGHT RESTRICTIONS AT KRIC...KSBY AND KPHF MON MORNING...WITH MVFR POSSIBLE AT KORF AND KECG. CONDITIONS SHOULD BECOME VFR AT ALL SITES BY 13Z MON. A SCT CU DECK WILL PREVAIL WITH VERY ISOLATED SHOWERS ARE POSSIBLE MON AFTERNOON. PRECIP CHANCES WILL CONTINUE TO INCREASE TUE INTO WED AS A COLD FRONT APPROACHES THE FORECAST AREA FROM THE WEST. && .MARINE... NO HEADLINES ARE IN EFFECT WITH THIS ISSUANCE. SE TO S WINDS SHOULD HOLD JUST BELOW SCA CRITERIA OVER THE BAY. SEAS ARE JUST BELOW 5 FT IN THE NORTH CAROLINA COASTAL WATERS AND WAVEWATCH HAS THOSE SEAS DIMINISHING THROUGH THE EVENING AND OVERNIGHT HOURS. SOUTH WINDS INCREASE TOWARD MID WEEK AS A COLD FRONT APPROACHES FROM THE WEST. SCA CONDITIONS MAY DEVELOP IN PORTIONS OF THE AREA LATE TUESDAY OR WEDNESDAY. THE WIND FIELD WILL BE IMPACTED BY THE PROXIMITY OF TROPICAL SYSTEM (OR REMNANTS) BERYL LATE WEDNESDAY AND WEDNESDAY NIGHT...RESULTING IN DECREASING SOUTHERLY WINDS. WINDS THEN TURN TO NW/N BEHIND A COLD FRONT THURSDAY MORNING. IT NOW APPEARS THAT THE CONDITIONS BEHIND THE FRONT WILL REMAIN BELOW SCA. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SYNOPSIS...LKB NEAR TERM...AJZ/LKB SHORT TERM...LKB LONG TERM...LSA AVIATION...DAP MARINE...LSA
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
337 PM EDT SAT MAY 26 2012 .SYNOPSIS... A RIDGE OF HIGH PRESSURE ALOFT WILL PROVIDE UNSEASONABLY WARM AND HUMID WEATHER FOR THE HOLIDAY WEEKEND. A STALLED FRONT OVER THE REGION MAY HELP TO SPARK SHOWERS AND THUNDERSTORMS EACH AFTERNOON. A COLD FRONT WILL APPROACH TUESDAY. && .NEAR TERM /UNTIL MIDNIGHT TONIGHT/... STALLED FRONT CONTINUES TO BISECT OUR CWA. THIS CAN BE BEST SEEN IN THE DEWPOINT GRADIENT FROM NORTHEAST TO SOUTHWEST ACROSS THE REGION. THIS...ALONG WITH AN UPPER LEVEL SHORTWAVE...WILL WORK AS A MECHANISM FOR SHOWER AND THUNDERSTORM DEVELOPMENT...ESPECIALLY ALONG THE RIDGES AND POINTS SOUTH OF THE FRONT...WHERE CAPPING IS WEAKEST. THE MOST RECENT WRF-NMM AND HRRR RUNS SUGGEST THUNDERSTORMS WILL DEVELOP ALONG THE INSTABILITY AXIS RUNNING THROUGH CENTRAL PA INTO SOUTHWESTERN PA/NORTHERN WV THOUGH THERE HAS YET TO BE MUCH IN THE WAY OF TOWERING CUMULUS DEVELOPMENT UP TO THIS POINT OVER OUR AREA. STILL WITH THE MOST RECENT MESO ANALYSIS SUGGESTING 3500 J/KG OF CAPE AND LOW LEVEL DEWPOINTS STILL WELL INTO THE 60`S SOUTH OF THE FRONT...THINK THUNDERSTORM COVERAGE SHOULD INCREASE. UPPER LEVEL FLOW IS RELATIVELY WEAK SO ANY SHOWERS/THUNDERSTORMS THAT DO DEVELOP WILL BE SLOW MOVING AND DISORGANIZED. CHANCES SHOULD DECREASE AFTER SUNSET WITH THE LOSS OF HEATING. && .SHORT TERM /MIDNIGHT TONIGHT THROUGH TUESDAY/... SUNDAY AND MONDAY SHOULD BE MUCH LIKE SATURDAY AS THE HIGH PRESSURE RIDGE CONTINUES TO DOMINATE. THE NAM WANTS TO BRING A MCS ACROSS THE REGION EARLY SUNDAY BEFORE THE FRONT THAT WAS STALLED OVER THE REGION SATURDAY BEGINS TO LIFT AS A WARM FRONT...SPARKING SHOWERS AND THUNDERSTORMS ONCE AGAIN IN THE AFTERNOON. WITH LOW CONFIDENCE IN THE THUNDERSTORM COVERAGE AND WHETHER THE MCS WILL MAKE IT...KEPT SLIGHT CHANCE WORDING ONCE AGAIN SUNDAY. HIGH PRESSURE WILL MOVE TOWARDS THE EAST COAST MONDAY BRINGING A RETURN OF SOUTHERLY FLOW. WILL CONTINUE SLIGHT CHANCE WORDING FOR DIURNAL THUNDERSTORMS AS THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND INSTABILITY. QUESTION WILL BE WHETHER THERE WILL BE ENOUGH FORCING WITH THE UPPER RIDGE CENTERED OVERHEAD TO ASSIST IN THUNDERSTORM DEVELOPMENT. MODELS ARE IN GOOD AGREEMENT ON THE FRONTAL PASSAGE PROGGED FOR LATE TUESDAY. WITH PLENTY OF INSTABILITY AND HEATING...EXPECT SHOWERS AND THUNDERSTORMS TO DEVELOP OUT AHEAD OF THE FRONT ONCE AGAIN TUESDAY AFTERNOON. THUS...BROUGHT IN HIGH CHANCE WORDING BY THE AFTERNOON. MAINTAINED TEMPERATURES NEAR MAV/MEX GUIDANCE OF 15 DEGREES ABOVE NORMAL SUNDAY AND MEMORIAL DAY AS 850HPA TEMPERATURES INCREASE TO ALMOST 20C OVERHEAD. WITH CLOUD COVER AND PRECIPITATION CHANCES INCREASING TUESDAY...KEPT TEMPERATURES A LITTLE COOLER BUT STILL ABOUT 10 DEGREES ABOVE NORMAL. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... COLD FRONT WILL BE CROSSING REGION TUESDAY NIGHT WITH SHOWERS AND THUNDERSTORMS ENDING WEST TO EAST AS NORTHWEST FLOW BEHIND FRONT BRINGS IN COOLER AND LESS HUMID CONDITIONS. A GENERALLY DRY FORECAST WEDNESDAY AND INTO EARLY THURSDAY UNDER A FLAT TROUGH ACROSS THE EASTERN U.S. AND WEAK SURFACE RIDGE. BY LATE THURSDAY INTO FRIDAY FRONT WILL BEGIN TO COME BACK NORTH AS LOW PRESSURE DEVELOPS ACROSS THE LOWER OHIO VALLEY BRINGING IN SHOWERS AND PERHAPS A THUNDERSTORMS. FOR LATE WEEK INTO THE WEEKEND MODELS DEPICTING A RATHER STRONG UPPER TROUGH ACROSS THE EASTERN U.S. FOR THE BEGINNING OF JUNE WITH WELL BELOW NORMAL TEMPERATURES. CHANCE POPS CONTINUED INTO SATURDAY AS SURFACE LOW MOVES TO NEW ENGLAND WITH INSTABILITY SHOWERS UNDER COLD POOL ALOFT. CLOSE TO HPC PROGS. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... WASHED OUT FRONTAL BOUNDARY STRETCHED OUT FROM KPHD TO KPIT AND KIDI WILL MOVE LITTLE THROUGH SUNDAY. AS UPPER LEVEL RIDGE BUILDS ACROSS THE LOWER OHIO VALLEY MCS ACTIVITY ACROSS THE WESTERN LAKES LOOKS TO BE SHUNTED NORTH OF REGION THROUGH SUNDAY. VFR WITH GENERALLY LIGHT WINDS. .OUTLOOK...SUNDAY NIGHT THROUGH THURSDAY... GENERAL VFR CONDITIONS WILL PREVAIL THROUGH MONDAY WITH UPPER RIDGE ALOFT. ISOLATED THUNDERSTORMS POSSIBLE MONDAY IN LOW LEVEL INSTABILITY. ON TUESDAY...A COLD FRONT WILL BRING SHOWERS AND THUNDERSTORMS WITH THE POTENTIAL FOR RESTRICTIONS INTO TUESDAY NIGHT. SURFACE HIGH PRESSURE WILL BRING GENERAL VFR WEDNESDAY INTO THURSDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
740 PM EDT SUN MAY 27 2012 .SYNOPSIS... ISSUED AT 434 PM EDT SUN MAY 27 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER ERN MT AND A RIDGE FROM THE SE CONUS TO NRN SASK. AT THE SFC...A 999 MB LOW WAS LOCATED OVER SE NORTH DAKOTA WITH A WARM FRONT THROUGH CNTRL MN TO SE WI WHILE THE COLD FRONT EXTENDED THROUGH ERN SOUTH DAKOTA INTO NW KS. LEFTOVER LOWER CLOUDS OVER UPPER MI WERE THINNING OUT DURING THE AFTERNOON BUT HAVE KEPT TEMPS GENERALLY IN THE UPPER 60S TO LOWER 70S. CAPPING WITH SUBSTANTIAL 850-700 MB WARMING HAS SUPPRESSED ANY ADDITIONAL TSRA THIS AFTERNOON. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 434 PM EDT SUN MAY 27 2012 TONIGHT...EXPECT MAINLY DRY WEATHER TO PERSIST THIS EVENING OVER THE CWA. THE POTENTIAL FOR SOME SHRA/TSRA INTO UPPER MI BY LATE EVENING STILL REMAINS GIVEN THE PROXIMITY OF THE 850 MB WARM FRONT AND FAVORABLE 925-850 MB THETA-E ADVECTION. OTHERWISE...MAIN AREA OF CONVECTION IS EXPECTED TO DEVELOP ALONG THE COLD FRONT OVER MN AND THEN SPREAD TOWARD UPPER MI LATE TONIGHT. ALTHOUGH SHRA/TSRA AHEAD OF THE FRONT WOULD BE ARRIVING WHEN LOW LEVEL INSTABILITY IS WEAKER...MUCAPE VALUES STILL IN THE 1K-2K RANGE ALONG WITH FAVORABLE DEEP LAYER SHEAR MAY SUPPORT SOME STRONG TO SEVERE TSRA OVER THE WEST LATE WITH THE POTENTIAL FOR STRONG WINDS AND HAIL. MONDAY...AS THE SFC LOW MOVES FROM NRN MN ACROSS NRN LAKE SUPERIOR IT WILL DRAG A TROUGH ACROSS UPPER MI REACHING CNTRL UPPER MI AROUND 18Z. WITH 850 MB TEMPS STILL NEAR 19C OVER CNTRL UPPER MI...TEMPS COULD QUICKLY CLIMB INTO THE MID AND UPPER 80S BY EARLY AFTERNOON OVER CNTRL UPPER MI AND BOOST MLCAPE VALUES INTO THE 1500-2000 J/KG RANGE. ALTHOUGH THE STRONGER MID AND UPPER LEVEL DYNAMICS WILL REMAIN TO THE WEST WITH A SHORTWAVE TROUGH LIFTING FORM NE MN INTO NRN ONTARIO...THE COMBINATION OF STRONG INSTABILITY AND LOW LEVEL CONVERGENCE ALONG NEAR THE TROUGH AND LAKE BREEZE BOUNDARIES WILL STILL SUPPORT SCT TSRA DURING THE AFTERNOON...MAINLY OVER THE ERN HALF OF THE CWA WITH THE THREAT FOR ISOLD STORMS WITH DAMAGING WINDS OR LARGE HAIL. TO THE WEST...MID LEVEL DRYING WITH THE DRY SLOT SHOULD INHIBIT TSRA CHANCES. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 434 PM EDT SUN MAY 27 2012 THE PERIOD STARTS 00Z TUE WITH A 500MB LOW OVER NERN ND AND A 500MB RIDGE FROM THE LOWER GREAT LAKES TO JAMES BAY. THERE WILL BE AN ELONGATED 998MB SFC LOW FROM NEAR THE UPPER LOW TO ONTARIO BETWEEN LAKE SUPERIOR AND JAMES BAY. A COLD FRONT WILL BE OVER FAR ERN UPPER MI...WHICH IS AN AVG TIMING FROM GUIDANCE. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ALONG THE COLD FRONT. BY 12Z TUE...THE UPPER LOW WILL HAVE OPENED TO A TROUGH AND MOVED TO THE MN ARROWHEAD. THIS BRINGS COLDER AIR AS 850MB TEMPS FALL TO 3C NW TO 9C SE. BY 00Z WED THE ORIGINAL UPPER TROUGH AXIS WILL BE NE OF LAKE SUPERIOR...WHILE ANOTHER UPPER TROUGH ROTATES AROUND THE ORIGINAL TROUGH O TO FAR WRN ONTARIO. 850MB TEMPS WILL CONTINUE TO FALL TO AROUND 0C NW TO AROUND 6C SE BY 00Z WED. WITH THE UPPER TROUGH MOVING OVERHEAD TUE...ENOUGH INSTABILITY WILL DEVELOP FOR SOME INLAND SHOWERS. WED WILL BE THE COLDEST DAY OF THE WEEK AS THE SECOND UPPER TROUGH MOVES TO THE CENTRAL CWA BY 18Z WED...BRINGING 850MB TEMPS AROUND -2C UNDER NW FLOW. THIS RESULTS IN WED HIGHS IN THE 40S NEAR LAKE SUPERIOR AND IN THE 50S INLAND. WED NIGHT WILL CONTINUE TO COLD TREND AS A WEAK UPPER RIDGE BRIEFLY MOVES OVERHEAD. THIS ALLOWS FOR LIGHTER WINDS AND SUBSIDENCE THAT WILL MAKE FOR OVERNIGHT LOW AROUND FREEZING INLAND TO THE UPPER 30S NEAR THE GREAT LAKES SHORES. A SFC RIDGE WILL DOMINATE THE FORECAST THU THROUGH NEXT SUN...WITH LITTLE OR NO PRECIP EXPECTED. TEMPERATURES WILL SHOW A GENERAL WARMING TREND...WITH HIGHS EXPECTED TO BE IN THE 70S OVER MOST OF THE AREA NEXT WEEKEND. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 739 PM EDT SUN MAY 27 2012 AS A WARM FRONT MOVES NORTHWARD ACROSS THE AREA DURING THE TAF PERIOD...EXPECT IFR CONDITIONS TO RETURN TONIGHT AT CMX/SAW WITH MOIST UPSLOPE E TO SSE FLOW. SOME SHOWERS AND ASSOCIATED FOG MAY APPROACH IWD AND CMX AFTER 08Z...HOWEVER CONFIDENCE WAS TOO LOW TO INCLUDE THE MENTION OF VCTS AT THIS TIME. AS WINDS TURN TO A MORE WESTERLY DIRECTION AFTER THE PASSAGE OF THE WARM FRONT TOMORROW...AND STRONGER WINDS ARE ABLE TO MIX TO THE SURFACE...EXPECT LEFTOVER IFR CONDITIONS TO BEGIN LIFTING VFR BY EARLY AFTERNOON. MODELS ARE IN LOW AGREEMENT FOR BOTH TIMING AND VIS/CIGS...SO WILL CONTINUE TO MONITOR IN CASE UPDATES NEED TO BE MADE. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 434 PM EDT SUN MAY 27 2012 LOW PRESSURE LIFTING NE THROUGH THE NRN PLAINS AND A WARM FRONT NEAR SRN LAKE SUPERIOR WILL RESULT IN GUSTY EAST-NORTHEAST WINDS OF 20 TO 30 KT THIS EVENING ...ESPECIALLY OVER THE WESTERN THIRD OF LAKE SUPERIOR. SOUTHWEST TO WEST WINDS TO 25 KTS MAY OCCUR ON TUESDAY IN WAKE OF THE FRONT...ESPECIALLY OVR WRN AND NCNTRL LAKE SUPERIOR AROUND ISLE ROYALE AND THE KEWEENAW PENINSULA. WINDS VEERING NORTHWEST TUE NIGHT BEHIND A SECONDARY COLD FRONT COULD THEN REMAIN GUSTY TO 25 KTS OVER EASTERN LK SUPERIOR INTO WEDNESDAY MORNING. WINDS WILL DIMINISH LATER WEDNESDAY AS HIGH PRESSURE BUILDS BACK OVER THE AREA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...JLB SHORT TERM...JLB LONG TERM...TITUS AVIATION...JMW MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
432 PM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 430 PM EDT SAT MAY 26 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LOW OVER THE GREAT BASIN AND A RIDGE OVER THE SE CONUS RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE UPPER MS VALLEY AND WRLY FLOW ACROSS THE NRN GREAT LAKES. THE MAIN SHORTWAVE WAS ROTATING THROUGH UT/NRN AZ. AT THE SFC...E TO SE FLOW WAS DEVELOPING BTWN HIGH PRES OVER NRN ONTARIO AND A WARM FRONT FROM CNTRL IA INTO NRN IL. AREAS OF CONVECTION HAVE DEVELOPED OVER SRN MN INTO SW WI...CLOSER TO THE 850 MB WARM FRONT. A BAND OF -SHRA...MAINLY SPRINKLES OVER SRN UPPER MI WAS DIMINISHING AT IT MOVES EAST INTO THE DRIER MORE STABLE AIRMASS. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 430 PM EDT SAT MAY 26 2012 TONIGHT...AS THE UT/AZ SHRTWV MOVES TOWARD NE WY AND WRN ND AND THE ASSOCIATED SFC LOW MOVES NORTH THROUGH THE DAKOTAS...THE SFC-850 MB WARM FRONT WILL ALSO GRADUALLY LIFT NORTH. MDLS STILL IN GOOD AGREEMENT SHOWING STRONG 925-850 MB MOISTURE TRANSPORT INTO THE UPPER MS VALLEY AND WRN GREAT LAKES THAT WILL SUPPORT A BROAD AREA OF SHRA/TSRA. THERE IS STILL CONSIDERABLE MODEL UNCERTAINTY ON WHERE THE HEAVIER RAIN WILL FALL. EXPECT INCREASE IN SHRA/TSRA LATE THIS EVENING AND OVERNIGHT WITH STRENGTHENING LLJ. SIMILAR TO TODAY...EXPECT THE FOCUS FOR HEAVIER CONVECTION ALONG THE WI BDR AND NRN LAKE MICHIGAN IN CLOSER PROXIMITY TO THE 850 MB WARM FRONT AND BEST 305K ISENTROPIC ASCENT. SUNDAY...ADDITIONAL SHRA/TSRA ARE LIKELY DURING THE MORNING BEFORE THE 850 MB WARM FRONT LIFTS TO THE NORTH OF THE CWA. EXPECT INCREASED MID-LVL DRYING/WARMING TO HELP CAP CONVECTION OVER SRN COUNTIES BY AFTERNOON. WITH THE SFC WARM FRONT DRAPED OVER THE THE AREA...TEMPS COULD CLIMB WELL INTO THE 80S ALONG THE WI BDR BUT REMAIN RELATIVELY COOL (LOWER 60S) OVER THE KEWEENAW PENINSULA IN AN ERLY FLOW AND ALONG LAKE MI IN A SRLY FLOW. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 430 PM EDT SAT MAY 26 2012 MAIN FOCUS IN THE LONG TERM IS ON PRECIP/CONVECTION CHANCES SUN NIGHT THROUGH MON...AND WITH SEVERE POTENTIAL MON AFTERNOON. PERIOD STARTS 00Z MON WITH A DEEP 500MB LOW OVER FAR NE MT AND A 500MB RIDGE AXIS FROM THE SE CONUS...OVER OUR CWA...AND INTO CENTRAL MANITOBA. AT THE SFC THERE WILL BE A LOW E OF THE UPPER LOW...WITH A WARM FRONT MOVING INTO THE SRN CWA. MODELS ARE IN PRETTY GOOD GENERAL AGREEMENT WITH THIS SYSTEM...INCLUDING WHEN IT MOVES E THROUGH THE WEEK. SUN NIGHT...WITH THE WARM FRONT NEAR OR OVER THE SRN CWA TO START THE NIGHT OFF...EXPECT SOME SHOWERS AND THUNDERSTORMS SUN NIGHT...BUT WITH THE UPPER RIDGE AXIS BEING OVER THE CWA /SO REALLY NO UPPER SUPPORT/ AND RELATIVELY DRY AIRMASS OVERHEAD MOST OF THE PRECIP SHOULD BE OVER N AND W LAKE SUPERIOR. WITH 850MB TEMPS AROUND 19C AND SW FLOW...EXPECT WARM OVERNIGHT LOWS IN THE 50S TO UPPER 60S /WARMEST IN DOWNSLOPING AREAS NEAR LAKE SUPERIOR/. MON...ATTENTION TURNS TO CONVECTION ASSOCIATED WITH THE COLD FRONT/SFC TROUGH THAT WILL MOVE THROUGH DURING THE DAY. MAIN DIFFERENCE BETWEEN MODELS AT THIS POINT IS THAT THE 00Z/26 ECMWF BRING THE COLD FRONT THROUGH ABOUT 6 HOURS FASTER THAN THE 12Z/26 GFS AND 12Z/26 NAM. PREFER THE SLOWER SOLUTIONS OF THE GFS AND NAM SINCE THE SYSTEM WILL BE PUSHING INTO THE STRONG UPPER RIDGE. THIS BRINGS THE COLD FRONT MOVING INTO THE WRN CWA AROUND 18Z MON...THEN TO THE CENTRAL CWA AROUND 00Z TUE...THEN EXITING THE E CWA AROUND 06Z TUE. THIS WOULD PROVIDE TIME FOR AMPLE HEATING AS 850MB TEMPS WILL BE AROUND 17C...RESULTING IN HIGHS IN THE MID 70S TO NEAR 90...WARMEST OVER THE SOUTH CENTRAL. THERE SHOULD BE AROUND 1000J/KG OF SBCAPE IN THIS ENVIRONMENT...WITH POTENTIAL FOR UP TO 1500J/KG. 0-6KM BULK SHEAR LOOKS TO BE 60-70KTS...BUT 0-1KM SHEAR WILL BE LOWER AT AROUND 15KTS. IT STILL LOOKS PRETTY DRY THROUGHOUT FORECAST SOUNDINGS...WHICH WOULD ACT TO LIMIT PRECIP. THE NAM SHOWS THE MOST MOISTURE...BUT THAT ALSO BRINGS AN 850MB JET UP INTO THE CWA...WHICH THE DRIER GFS KEEPS FARTHER S. TEND TO SUPPORT THE GFS IDEA HERE...AS THE JET AND MOISTURE TRANSPORT IS TYPICALLY BLOCKED BY ONGOING CONVECTION TO THE S...WHICH LOOKS FAVORABLE GIVEN THE JET NOSING INTO AN AREA OF HIGH CAPE OVER SRN WI/NRN IL. ALSO...THE UPPER LOW WILL ONLY HAVE MOVE TO EXTREME NW MN BY 00Z TUE...SO UPPER SUPPORT WILL BE SOMEWHAT LACKING. STILL...IF THUNDERSTORMS CAN FORM SOME OF THEM COULD BE STRONG TO SEVERE. THINK THE CHANCE OF SEVERE THUNDERSTORMS IS LOW ENOUGH NOT TO PUT IN THE HWO. AS FAR AS POPS GO...WILL KEEP BELOW LIKELY PERCENTAGES. THE UPPER LOW MOVES JUST N OF LAKE SUPERIOR TUE...WITH 850MB TEMPS FALLING FROM A CWA AVG OF AROUND 9C AT 12Z TUE...TO 6C BY 00Z WED. WITH PLENTY OF LOW LEVEL MOISTURE BEHIND THE FRONT...AND STEEPER LAPSE RATES AS THE UPPER LOW MOVES ACROSS...LOOKS LIKE WE MAY GET POP UP SHOWERS INLAND TUE AFTERNOON. HIGH TEMPS WILL STILL GET INTO THE LOW TO MID 60S OVER THE E AND CWA...WITH W UPPER MI SEEING HIGHS IN THE 50S. SECONDARY UPPER TROUGH SLIDES ACROSS THE CWA WED INTO EARLY THU...KEEPING TEMPS COOL AS 850MB TEMPS WILL BE -1C TO 1C WED. WARMER TEMPS MOVE IN BEHIND THE TROUGH LATE ON THU...WITH CWA AVG 850MB TEMPS AROUND 5C BY 00Z FRI. HIGHS WED LOOK TO BE IN THE 50S TO AROUND 60 S ON WED...AND IN THE MID 50S TO UPPER 60S THU. THEN EXPECT SOME WARMING FRI INTO NEXT SAT WITH DRY HIGH PRESSURE OVERHEAD...ALTHOUGH CONFIDENCE IS LOWER ON SAT AS MODELS HAVE MORE WIDELY VARYING SOLUTIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 153 PM EDT SAT MAY 26 2012 VFR CONDITIONS WILL PREVAIL INTO THIS EVENING DURING THE FORECAST PERIOD UNDER AN ERLY WIND FLOW. MAIN CONCERN WILL THEN BE INCOMING RAIN LATE THIS AFTERNOON AND TONIGHT ALONG THE INCOMING WARM FRONT. RAIN WILL START FIRST AT KIWD AND THEN MOVE INTO KCMX AND KSAW. WHEN THE RAIN INITIALLY ARRIVES...A LOWER VFR CIG IS LIKELY. EXPECT CIGS TO LOWER TO IFR LATE TONIGHT AND EARLY SUNDAY UNDER A MOIST EAST SOUTHEAST FLOW. WITH INCREASING INSTABILITY ALONG INCOMING WARM FRONT INCLUDED VCTS FOR KIWD EARLY IN THE EVENING INTO THE OVERNIGHT...AND AT KCMX AND KSAW AFT 06Z SUNDAY. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 430 PM EDT SAT MAY 26 2012 AS LOW PRESSURE DEVELOPS OVER PLAINS WHILE HIGH PRESSURE SLOWLY MOVES TO THE EAST TOWARD THE ATLANTIC SEABOARD. PRESSURE PATTERN RESULTS IN PRESSURE FALLS SPREADING INTO WESTERN LK SUPERIOR AND A FAVORABLE SETUP FOR STRONG GUSTY EAST-NORTHEAST WINDS OVR MUCH OF WESTERN THIRD OF LAKE SUPERIOR. EXPECT GUSTS OF 20 TO 30 KTS TONIGHT. SFC LOW AND WARM FRONT BEGIN TO MOVE ACROSS AREA ON SUNDAY AFTN WHICH SHOULD DIMINISH WINDS BY LATER IN THE DAY. SOUTH WINDS UP TO 25 KTS ARE POSSIBLE SUNDAY NIGHT INTO MONDAY OVER EASTERN SECTIONS OF LK SUPERIOR AHEAD OF THE COLD FRONT. WEST WINDS TO 25 KTS MAY OCCUR ON TUESDAY IN WAKE OF THE FRONT...ESPECIALLY OVR CNTRL LAKE SUPERIOR AROUND ISLE ROYALE AND THE KEWEENAW PENINSULA. NORTHWEST WINDS COULD THEN REMAIN GUSTY OVER EASTERN LK SUPERIOR INTO WEDNESDAY MORNING. WINDS DIMINISH LATER WEDNESDAY AS HIGH PRESSURE BUILDS BACK OVER THE AREA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...JLB SHORT TERM...JLB LONG TERM...TITUS AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
150 PM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .UPDATE... ISSUED AT 145 PM EDT SAT MAY 26 2012 PRECIPITATION HAS DIMINISHED STEADILY THIS AFTERNOON AND WILL NOW FEATURE LOWER POPS. STILL MONITORING UPSTREAM CONVECTION IN MN CLOSELY. A RISK EXIST FOR THIS TO TRACK INTO PARTS OF LOWER MI THIS EVENING. UPDATE ISSUED AT 1148 AM EDT SAT MAY 26 2012 ISSUED A FORECAST UPDATE TO ACCOUNT FOR NEXT BATCH OF RAIN CROSSING LAKE MI. THE RAIN HAS BEEN DISSIPATING. BUT IT APPEARS LIKELY THAT THE RAIN WILL MAKE IT INTO THE REGION SOUTH OF A HART TO ST JOHNS LINE THIS AFTERNOON. IT ALSO APPEARS THAT WE WILL SEE SOME SUN BY MID AFTERNOON. A COUPLE OF HOURS OF FILTERED SUN COULD STILL ALLOW FOR THE 70S THAT WE HAVE GOING FOR HIGHS. I DID UPDATE THE GRAPHICAST TO MENTION THAT THE WARMEST PART OF THE DAY WILL NOT BE UNTIL AFTER 4 PM. LOOKING UPSTREAM ANOTHER CLUSTER OF STORMS WAS TRACKING ALONG THE GRADIENT OF STEEPER MID LEVE LAPSE RATES NEAR MINNEAPOLIS. THIS GRADIENT DOES RUN INTO LOWER MI. SO AN ELEVATED RISK EXISTS FOR THE STORMS TO ROLL INTO LOWER MICHIGAN. CURRENT TIMING FOR THEM TO ARRIVE ON THE LAKESHORE COUNTIES WOULD BE AROUND 00Z SUN. HOWEVER THE STORMS COULD WEAKEN OR DISSIPATE BEFORE REACHING MI. THIS IS WHAT THE HRRR RUC IS SHOWING. WILL NEED TO MONITOR CLOSELY THE SITUATION THROUGH THE AFTERNOON. UPDATE ISSUED AT 920 AM EDT SAT MAY 26 2012 UPDATED PRODUCTS TO ACCOUNT FOR THE DECAYING MCS THAT WILL MOVE ACROSS THE REGION THIS MORNING. HIGHER POPS...LOWER TEMPS. WARMEST TEMPS TODAY MAY BE FROM LDM TO HARRISON IF SOME SUN UP THERE. THE RADAR TRENDS IN SRN WISCONSIN SUGGEST THE HEAVIER CELLS ON THE BACKSIDE OF THE MCS WILL SHIFT SOUTH AND MISS SW LOWER MI THIS AFTERNOON. THE HRRR RUC SAYS OTHERWISE. WILL KEEP MONITORING THE SITUATION CLOSELY. THE FORECAST FOR NOW WILL FEATURE LESS SHOWERS IN THE AFTERNOON AS COMPARED TO THIS MORNING. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM EDT SAT MAY 26 2012 NO SIGNIFICANT CHANGES TO THE FORECAST WERE MADE. MAIN FORECAST PROBLEM IS TIMING OF STORMS ALONG THE COLD FRONT LATE MONDAY INTO TUESDAY. WILL HAVE LOW CHANCE POPS FOR MONDAY AFTERNOON BUT EXPECT MAIN BATCH OF CONVECTION TO BE ARRIVING IN THE EVENING. USED A BLEND OF THE 00Z RUNS OF THE GFS AND SLOWER EURO AND WILL HAVE LIKELY POPS FOR MONDAY NIGHT. FRONT IS EAST OF THE FORECAST AREA TUESDAY WITH MORNING SHOWERS POSSIBLE ACROSS EASTERN ZONES THEN DRY AND COOLER FOR THE REST OF THE WEEK. LOW CONFIDENCE FORECAST FOR THE END OF THE WEEK AS THE 00Z EURO HAS LOST THE UPPER LOW THAT HAS BEEN INDICATED FORMING AT THE SOUTHERN END OF A SHARP UPPER TROUGH EXTENDING FROM AN UPPER LOW NEAR JAMES BAY. KEPT SLIGHT CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY FOR NOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 145 PM EDT SAT MAY 26 2012 KEPT THE FORECAST AS VFR. WILL NEED TO MONITOR THE STORMS AS THEY DEVELOP OVER THE MN TO WI TO MI AREA THIS EVENING. THE ATMOSPHERE IS BECOMING VERY UNSTABLE. MAY BE SOME BRIEF IFR AND GUSTY WINDS WITH ANY STORMS. THE INDICATIONS ARE THE THE STORMS WILL DECREASE IN COVERAGE FROM SUNDAY AM TO SUNDAY AFTERNOON. THIS COULD CHANGE DEPENDING ON HOW THE STORMS EVOLVE. && .MARINE... ISSUED AT 920 AM EDT SAT MAY 26 2012 THE NEARSHORE FORECAST FEATURE MORE IN THE WAY OF SHOWERS AND STORMS FOR TODAY. OUTSIDE OF ANY STORMS IT APPEARS THE WINDS WILL REMAIN LOW ENOUGH TO KEEP THE WAVES UNDER 3 FEET. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...MJS SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...MJS HYDROLOGY...93 MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1200 PM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .UPDATE... ISSUED AT 1148 AM EDT SAT MAY 26 2012 ISSUED A FORECAST UPDATE TO ACCOUNT FOR NEXT BATCH OF RAIN CROSSING LAKE MI. THE RAIN HAS BEEN DISSIPATING. BUT IT APPEARS LIKELY THAT THE RAIN WILL MAKE IT INTO THE REGION SOUTH OF A HART TO ST JOHNS LINE THIS AFTERNOON. IT ALSO APPEARS THAT WE WILL SEE SOME SUN BY MID AFTERNOON. A COUPLE OF HOURS OF FILTERED SUN COULD STILL ALLOW FOR THE 70S THAT WE HAVE GOING FOR HIGHS. I DID UPDATE THE GRAPHICAST TO MENTION THAT THE WARMEST PART OF THE DAY WILL NOT BE UNTIL AFTER 4 PM. LOOKING UPSTREAM ANOTHER CLUSTER OF STORMS WAS TRACKING ALONG THE GRADIENT OF STEEPER MID LEVE LAPSE RATES NEAR MINNEAPOLIS. THIS GRADIENT DOES RUN INTO LOWER MI. SO AN ELEVATED RISK EXISTS FOR THE STORMS TO ROLL INTO LOWER MICHIGAN. CURRENT TIMING FOR THEM TO ARRIVE ON THE LAKESHORE COUNTIES WOULD BE AROUND 00Z SUN. HOWEVER THE STORMS COULD WEAKEN OR DISSIPATE BEFORE REACHING MI. THIS IS WHAT THE HRRR RUC IS SHOWING. WILL NEED TO MONITOR CLOSELY THE SITUATION THROUGH THE AFTERNOON. UPDATE ISSUED AT 920 AM EDT SAT MAY 26 2012 UPDATED PRODUCTS TO ACCOUNT FOR THE DECAYING MCS THAT WILL MOVE ACROSS THE REGION THIS MORNING. HIGHER POPS...LOWER TEMPS. WARMEST TEMPS TODAY MAY BE FROM LDM TO HARRISON IF SOME SUN UP THERE. THE RADAR TRENDS IN SRN WISCONSIN SUGGEST THE HEAVIER CELLS ON THE BACKSIDE OF THE MCS WILL SHIFT SOUTH AND MISS SW LOWER MI THIS AFTERNOON. THE HRRR RUC SAYS OTHERWISE. WILL KEEP MONITORING THE SITUATION CLOSELY. THE FORECAST FOR NOW WILL FEATURE LESS SHOWERS IN THE AFTERNOON AS COMPARED TO THIS MORNING. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM EDT SAT MAY 26 2012 NO SIGNIFICANT CHANGES TO THE FORECAST WERE MADE. MAIN FORECAST PROBLEM IS TIMING OF STORMS ALONG THE COLD FRONT LATE MONDAY INTO TUESDAY. WILL HAVE LOW CHANCE POPS FOR MONDAY AFTERNOON BUT EXPECT MAIN BATCH OF CONVECTION TO BE ARRIVING IN THE EVENING. USED A BLEND OF THE 00Z RUNS OF THE GFS AND SLOWER EURO AND WILL HAVE LIKELY POPS FOR MONDAY NIGHT. FRONT IS EAST OF THE FORECAST AREA TUESDAY WITH MORNING SHOWERS POSSIBLE ACROSS EASTERN ZONES THEN DRY AND COOLER FOR THE REST OF THE WEEK. LOW CONFIDENCE FORECAST FOR THE END OF THE WEEK AS THE 00Z EURO HAS LOST THE UPPER LOW THAT HAS BEEN INDICATED FORMING AT THE SOUTHERN END OF A SHARP UPPER TROUGH EXTENDING FROM AN UPPER LOW NEAR JAMES BAY. KEPT SLIGHT CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY FOR NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 744 AM EDT SAT MAY 26 2012 WILL CONTINUE MONITORING AN AREA OF RAIN AND THUNDERSTORMS ACROSS SOUTHERN WI / NORTHERN IL THIS MORNING AS IT PRESSES EAST AND GRADUALLY WEAKENS. CIGS AND VISBYS WITHIN THIS BATCH OF PRECIPITATION HAVE BEEN AROUND 4K-5K FT WITH REDUCTIONS TO 5 MILES OR LESS AT TIMES. WILL FEATURE SIMILAR CONDITIONS PRIMARILY FOR AZO AND BTL AS THIS RAIN MOVES ACROSS THE LAKE. EXPECTING OCCASIONAL SHRA WITH VCTS TODAY WITH LOW CHANCE FOR IFR CONDITIONS. BRIEF REDUCTIONS IN CIGS/VISBYS TO IFR LEVELS ARE POSSIBLE IN THE HEAVIEST SHRA AND TSRA. BETWEEN 00Z-06Z...ANOTHER ROUND OF SHRA AND/OR TSRA IS POSSIBLE AS A WARM FRONT LIFTS THROUGH THE REGION. I BELIEVE THE THREAT WOULD BE MORE FOR MKG/GRR/LAN AND INTO NORTHERN MI WITH THAT NEXT ROUND OF PRECIPITATION. && .MARINE... ISSUED AT 920 AM EDT SAT MAY 26 2012 THE NEARSHORE FORECAST FEATURE MORE IN THE WAY OF SHOWERS AND STORMS FOR TODAY. OUTSIDE OF ANY STORMS IT APPEARS THE WINDS WILL REMAIN LOW ENOUGH TO KEEP THE WAVES UNDER 3 FEET. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...MJS SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...HOVING HYDROLOGY...93 MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
927 AM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .UPDATE... ISSUED AT 920 AM EDT SAT MAY 26 2012 UPDATED PRODUCTS TO ACCOUNT FOR THE DECAYING MCS THAT WILL MOVE ACROSS THE REGION THIS MORNING. HIGHER POPS...LOWER TEMPS. WARMEST TEMPS TODAY MAY BE FROM LDM TO HARRISON IF SOME SUN UP THERE. THE RADAR TRENDS IN SRN WISCONSIN SUGGEST THE HEAVIER CELLS ON THE BACKSIDE OF THE MCS WILL SHIFT SOUTH AND MISS SW LOWER MI THIS AFTERNOON. THE HRRR RUC SAYS OTHERWISE. WILL KEEP MONITORING THE SITUATION CLOSELY. THE FORECAST FOR NOW WILL FEATURE LESS SHOWERS IN THE AFTERNOON AS COMPARED TO THIS MORNING. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM EDT SAT MAY 26 2012 NO SIGNIFICANT CHANGES TO THE FORECAST WERE MADE. MAIN FORECAST PROBLEM IS TIMING OF STORMS ALONG THE COLD FRONT LATE MONDAY INTO TUESDAY. WILL HAVE LOW CHANCE POPS FOR MONDAY AFTERNOON BUT EXPECT MAIN BATCH OF CONVECTION TO BE ARRIVING IN THE EVENING. USED A BLEND OF THE 00Z RUNS OF THE GFS AND SLOWER EURO AND WILL HAVE LIKELY POPS FOR MONDAY NIGHT. FRONT IS EAST OF THE FORECAST AREA TUESDAY WITH MORNING SHOWERS POSSIBLE ACROSS EASTERN ZONES THEN DRY AND COOLER FOR THE REST OF THE WEEK. LOW CONFIDENCE FORECAST FOR THE END OF THE WEEK AS THE 00Z EURO HAS LOST THE UPPER LOW THAT HAS BEEN INDICATED FORMING AT THE SOUTHERN END OF A SHARP UPPER TROUGH EXTENDING FROM AN UPPER LOW NEAR JAMES BAY. KEPT SLIGHT CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY FOR NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 744 AM EDT SAT MAY 26 2012 WILL CONTINUE MONITORING AN AREA OF RAIN AND THUNDERSTORMS ACROSS SOUTHERN WI / NORTHERN IL THIS MORNING AS IT PRESSES EAST AND GRADUALLY WEAKENS. CIGS AND VISBYS WITHIN THIS BATCH OF PRECIPITATION HAVE BEEN AROUND 4K-5K FT WITH REDUCTIONS TO 5 MILES OR LESS AT TIMES. WILL FEATURE SIMILAR CONDITIONS PRIMARILY FOR AZO AND BTL AS THIS RAIN MOVES ACROSS THE LAKE. EXPECTING OCCASIONAL SHRA WITH VCTS TODAY WITH LOW CHANCE FOR IFR CONDITIONS. BRIEF REDUCTIONS IN CIGS/VISBYS TO IFR LEVELS ARE POSSIBLE IN THE HEAVIEST SHRA AND TSRA. BETWEEN 00Z-06Z...ANOTHER ROUND OF SHRA AND/OR TSRA IS POSSIBLE AS A WARM FRONT LIFTS THROUGH THE REGION. I BELIEVE THE THREAT WOULD BE MORE FOR MKG/GRR/LAN AND INTO NORTHERN MI WITH THAT NEXT ROUND OF PRECIPITATION. && .MARINE... ISSUED AT 920 AM EDT SAT MAY 26 2012 THE NEARSHORE FORECAST FEATURE MORE IN THE WAY OF SHOWERS AND STORMS FOR TODAY. OUTSIDE OF ANY STORMS IT APPEARS THE WINDS WILL REMAIN LOW ENOUGH TO KEEP THE WAVES UNDER 3 FEET. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ UPDATE...MJS SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...HOVING HYDROLOGY...93 MARINE...MJS
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
746 AM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM EDT SAT MAY 26 2012 NO SIGNIFICANT CHANGES TO THE FORECAST WERE MADE. MAIN FORECAST PROBLEM IS TIMING OF STORMS ALONG THE COLD FRONT LATE MONDAY INTO TUESDAY. WILL HAVE LOW CHANCE POPS FOR MONDAY AFTERNOON BUT EXPECT MAIN BATCH OF CONVECTION TO BE ARRIVING IN THE EVENING. USED A BLEND OF THE 00Z RUNS OF THE GFS AND SLOWER EURO AND WILL HAVE LIKELY POPS FOR MONDAY NIGHT. FRONT IS EAST OF THE FORECAST AREA TUESDAY WITH MORNING SHOWERS POSSIBLE ACROSS EASTERN ZONES THEN DRY AND COOLER FOR THE REST OF THE WEEK. LOW CONFIDENCE FORECAST FOR THE END OF THE WEEK AS THE 00Z EURO HAS LOST THE UPPER LOW THAT HAS BEEN INDICATED FORMING AT THE SOUTHERN END OF A SHARP UPPER TROUGH EXTENDING FROM AN UPPER LOW NEAR JAMES BAY. KEPT SLIGHT CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY FOR NOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 744 AM EDT SAT MAY 26 2012 WILL CONTINUE MONITORING AN AREA OF RAIN AND THUNDERSTORMS ACROSS SOUTHERN WI / NORTHERN IL THIS MORNING AS IT PRESSES EAST AND GRADUALLY WEAKENS. CIGS AND VISBYS WITHIN THIS BATCH OF PRECIPITATION HAVE BEEN AROUND 4K-5K FT WITH REDUCTIONS TO 5 MILES OR LESS AT TIMES. WILL FEATURE SIMILAR CONDITIONS PRIMARILY FOR AZO AND BTL AS THIS RAIN MOVES ACROSS THE LAKE. EXPECTING OCCASIONAL SHRA WITH VCTS TODAY WITH LOW CHANCE FOR IFR CONDITIONS. BRIEF REDUCTIONS IN CIGS/VISBYS TO IFR LEVELS ARE POSSIBLE IN THE HEAVIEST SHRA AND TSRA. BETWEEN 00Z-06Z...ANOTHER ROUND OF SHRA AND/OR TSRA IS POSSIBLE AS A WARM FRONT LIFTS THROUGH THE REGION. I BELIEVE THE THREAT WOULD BE MORE FOR MKG/GRR/LAN AND INTO NORTHERN MI WITH THAT NEXT ROUND OF PRECIPITATION. && .MARINE... ISSUED AT 332 AM EDT SAT MAY 26 2012 THUNDERSTORMS WILL BE THE MAIN THREAT DURING THE WEEKEND. OUTSIDE OF STORMS...WINDS AND WAVES ARE NOT EXPECTED TO BE SIGNIFICANT. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...HOVING HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
339 AM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY) ISSUED AT 339 AM EDT SAT MAY 26 2012 NO SIGNIFICANT CHANGES TO THE FORECAST WERE MADE. MAIN FORECAST PROBLEM IS TIMING OF STORMS ALONG THE COLD FRONT LATE MONDAY INTO TUESDAY. WILL HAVE LOW CHANCE POPS FOR MONDAY AFTERNOON BUT EXPECT MAIN BATCH OF CONVECTION TO BE ARRIVING IN THE EVENING. USED A BLEND OF THE 00Z RUNS OF THE GFS AND SLOWER EURO AND WILL HAVE LIKELY POPS FOR MONDAY NIGHT. FRONT IS EAST OF THE FORECAST AREA TUESDAY WITH MORNING SHOWERS POSSIBLE ACROSS EASTERN ZONES THEN DRY AND COOLER FOR THE REST OF THE WEEK. LOW CONFIDENCE FORECAST FOR THE END OF THE WEEK AS THE 00Z EURO HAS LOST THE UPPER LOW THAT HAS BEEN INDICATED FORMING AT THE SOUTHERN END OF A SHARP UPPER TROUGH EXTENDING FROM AN UPPER LOW NEAR JAMES BAY. KEPT SLIGHT CHANCE POPS FOR THURSDAY NIGHT AND FRIDAY FOR NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 142 AM EDT SAT MAY 26 2012 CONVECTION IS FIRING JUST NORTH OF THE SFC WARM FRONT OVER CENTRAL IOWA AND SLOWLY MOVING EAST. IF IT HOLDS TOGETHER THE TSRA WOULD MAKE IT TO THE LAKE SHORE AROUND 7 AM. FARTHER NORTH...SCT SHRA ARE MOVING EWD ALONG M-46. A FEW OF THESE SHOWERS MAY CLIP KMKG/KLAN PRIOR TO 12Z. AS THE WARM FRONT LIFTS NORTH...TSRA WILL BE POSSIBLE THROUGH MUCH OF THE PERIOD. && .MARINE... ISSUED AT 332 AM EDT SAT MAY 26 2012 THUNDERSTORMS WILL BE THE MAIN THREAT DURING THE WEEKEND. OUTSIDE OF STORMS...WINDS AND WAVES ARE NOT EXPECTED TO BE SIGNIFICANT. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...93 SHORT TERM...93 LONG TERM...OSTUNO AVIATION...93 HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
333 AM EDT SAT MAY 26 2012 .SYNOPSIS... ISSUED AT 332 AM EDT SAT MAY 26 2012 A WARM FRONT MOVING NORTH THIS WEEKEND WILL BE A FOCAL POINT FOR SHOWER AND THUNDERSTORM DEVELOPMENT. THE MAIN THUNDERSTORM THREAT AREA WILL MOVE NORTH OF M-46 SUNDAY AFTERNOON. A TRAILING COLD FRONT WILL MOVE ACROSS THE AREA LATE MONDAY BRINGING ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 332 AM EDT SAT MAY 26 2012 FORECAST CONCERNS DEAL WITH THE HEAT SUNDAY AND CONVECTIVE POTENTIAL THROUGH THE PERIOD. * SCATTERED TO NUMEROUS STORMS TODAY/TONIGHT...MAINLY NON-SEVERE. * HOT SUNDAY. HEAT INDICES UPPER 90S SOUTH ALONG/SOUTH OF I-94. LATEST REGIONAL RADAR SHOWS A DEVELOPING AREA OF THUNDERSTORMS ALONG AND NORTH OF I-80 ACROSS IOWA AND NRN IL. IT IS JUST NORTH OF THE SFC WARM FRONT AND CLOSE TO THE H8 TEMPERATURE GRADIENT. THIS AREA OF MID LEVEL TEMPERATURE ADVECTION AND STEEPER LAPSE RATES IS A FAVORED AREA OF TSRA DEVELOPMENT AND THIS MORNING IS NO EXCEPTION. THIS PCPN WAS GENERALLY MOVING EAST AND WEAKENING A BIT AS IT APPROACHED LAKE MICHIGAN. THIS ISN/T TOO SURPRISING GIVEN THAT THE LLJ IS VERY WEAK IN THIS AREA. LATEST HRRR SHOWS THIS PCPN SLOWLY WEAKENING AS IT HITS THE LAKE SHORE AROUND 11Z MAINLY NORTH OF I-96. ELEVATED INSTABILITY...INITIALLY ON THE LOW SIDE...WILL GRADUALLY INCREASE TODAY AS THE WARM FRONT MOVES NORTH. THE SFC LOW DRIVING THIS FRONT NWD IS IN WESTERN NEBRASKA AND SO WE SHOULD SEE THE GREATEST CONCENTRATION OF SVR STORMS WELL WEST OF THE CWA WHERE HEIGHT FALLS ARE GREATEST. THAT SAID...AN UPPER RIDGE NOSING INTO THE GREAT LAKES WILL FUNNEL SEVERAL SHORT WAVES ACROSS NRN IL/SRN LWR TODAY. THESE WAVES WILL ACT TO INCREASE COVERAGE AFTER 18Z TODAY AND INTO THE EVENING. WE HAVE INCREASED POPS TO COVER THIS LATE THIS AFTERNOON AND EVENING. THE WARM FRONT WILL BE NORTH OF THE CWA SUNDAY AND SO SHOULD MUCH OF THE TSRA ACTIVITY. WE/LL BECOME INCREASINGLY CAPPED AS THE UPPER RIDGE BUILDS IN. TEMPERATURES WILL CLIMB INTO THE LOWER TO MID 90S AND HEAT INDICES WILL CLIMB INTO THE UPPER 90S ALONG/SOUTH OF I-94. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 315 PM EDT FRI MAY 25 2012 THE MAIN CHALLENGES OF THE FCST IN THE LONG TERM WILL BE DEALING WITH THE HEAT AND CONVECTION SUN THROUGH MON NIGHT...AND THEN PCPN CHCS AND MUCH COOLER AIR FOR MID-LATE WEEK NEXT WEEK. MODELS HAVE BEEN FAIRLY CONSISTENT WITH REGARDS TO THE SUN THROUGH MON TIME FRAME OVER THE PAST COUPLE OF DAYS. MODELS ARE IN AGREEMENT IN MOVING THE FRONT NORTH THROUGH THE AREA BY SUN AFTERNOON. THIS WILL ALLOW FOR NOCTURNAL CONVECTION TO POSSIBLY AFFECT THE AREA FIRST THING SUN BEFORE MOVING NE OF THE AREA. WE EXPECT TO BREAK OUT IN PLENTY OF SUN AND TEMPS WILL CLIMB VERY QUICKLY WITH BREEZY SRLY WINDS. THE ATMOSPHERE SHOULD BECOME CAPPED AS H850 TEMPS WARM TO THE LOWER 20S C THROUGH MON. THESE TEMPS ALOFT WILL SUPPORT HIGH TEMPS IN THE LOW TO POSSIBLY MID 90S FOR SUN...AND MON IF THE CLOUDS HOLD OFF LONG ENOUGH. THERE IS A LITTLE DIFFERENCE WITH REGARD TO THE FRONTAL TIMING LATE MON AND MON NIGHT. THE GFS IS A LITTLE QUICKER WITH THE FRONT...AND WOULD SUPPORT A LITTLE BETTER CHC OF SEVERE WX LATE MON AFTERNOON/ MON EVENING. THE EURO IS A LITTLE SLOWER AND WOULD SUPPORT A FRONTAL TIMING MORE FOR MON NIGHT WHICH WOULD NEGATE THE INSTABILITY SLIGHTLY. WIND SHEAR VALUES ARE NOT TOO BAD IN THE 30-40 KNOT RANGE...SO STRONG TO SEVERE STORMS WILL BE POSSIBLE IF ENOUGH INSTABILITY IS PRESENT. WE ARE SIDING WITH THE SLIGHTLY SLOWER FRONTAL TIMING OF THE EURO...AND ARE CONCENTRATING THE HIGHEST POPS FOR MON NIGHT. THE FRONT AND ANY LINGERING PCPN SHOULD CLEAR THE AREA BY TUE AFTERNOON. WE WILL SEE A MARKED CHANGE IN THE WEATHER THEN FOR THE REMAINDER OF THE PERIOD. THE WRN TROUGH THAT IS RESPONSIBLE FOR BUILDING THE RIDGE THIS WEEKEND WILL BE LIFTING OUT TO THE NE MID WEEK NEXT WEEK. THIS WILL BE AMPLIFIED SOME BY ENERGY THAT WILL DIVE IN ON THE BACKSIDE OF IT FROM THE NW. TEMPS LOOK TO DROP BACK INTO THE 60S BY MID TO LATE WEEK. WE CAN NOT RULE OUT A FEW SHOWERS...HOWEVER THE EVOLUTION OF THE UPPER TROUGHING IS QUITE UNCERTAIN RIGHT NOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 142 AM EDT SAT MAY 26 2012 CONVECTION IS FIRING JUST NORTH OF THE SFC WARM FRONT OVER CENTRAL IOWA AND SLOWLY MOVING EAST. IF IT HOLDS TOGETHER THE TSRA WOULD MAKE IT TO THE LAKE SHORE AROUND 7 AM. FARTHER NORTH...SCT SHRA ARE MOVING EWD ALONG M-46. A FEW OF THESE SHOWERS MAY CLIP KMKG/KLAN PRIOR TO 12Z. AS THE WARM FRONT LIFTS NORTH...TSRA WILL BE POSSIBLE THROUGH MUCH OF THE PERIOD. && .MARINE... ISSUED AT 332 AM EDT SAT MAY 26 2012 THUNDERSTORMS WILL BE THE MAIN THREAT DURING THE WEEKEND. OUTSIDE OF STORMS...WINDS AND WAVES ARE NOT EXPECTED TO BE SIGNIFICANT. && .HYDROLOGY... ISSUED AT 332 AM EDT SAT MAY 26 2012 SCATTERED TO NUMEROUS THUNDERSTORMS ARE EXPECTED THROUGH THE HOLIDAY. SOME OF THE STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. WIDESPREAD FLOODING IS NOT EXPECTED. HOWEVER LOCALIZED FLOODING MAY BE POSSIBLE IN SOME OF THE STRONGER STORMS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...93 SHORT TERM...93 LONG TERM...NJJ AVIATION...93 HYDROLOGY...93 MARINE...93
AREA FORECAST DISCUSSION
NWS BILLINGS MT
859 PM MDT SUN MAY 27 2012 .SHORT TERM...VALID FOR MON AND TUE... ONLY MINOR CHANGES WERE MADE TO THE OVERNIGHT FORECAST...MAINLY TO LOWER TEMPERATURES A FEW DEGREES OUT OF RESPECT TO THE COOLING AIR MASS AND DEWPOINTS IN THE 30S F. THE BIAS-CORRECTED VERSION OF THE MULTI-MODEL CONSENSUS...WHICH HAS VERIFIED BEST IN THE PAST COUPLE OF DAYS...ALSO SUPPORTED DROPPING LOWS SLIGHTLY. OTHERWISE...THERE WILL BE CHANCE-STYLE POPS IN PLAY TONIGHT FOR THE LOWER ELEVATIONS WITH LINGERING CYCLONIC FLOW ALOFT ASSOCIATED WITH THE 500-HPA LOW IN NORTHEASTERN MT. THOUGH SOME OF THE SHOWERS WILL BE ENDING WITH SUNSET...THE PATTERN IS STILL SUPPORTIVE OF 30 TO 40 PERCENT POPS. THE MOIST NORTHWEST FLOW MAY ALSO YIELD A COUPLE INCHES OF SNOW IN THE CRAZY MOUNTAINS...WITH THE 00 UTC NAM AND RAP SNOW OUTPUT EVEN SUGGESTING 3 TO 4 INCHES IN THAT UPSLOPE REGION OVERNIGHT. SCHULTZ .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... MODELS AGREE ON TAKING A SHORTWAVE ACROSS MONTANA TUESDAY. THE GFS HAS SLOWED WITH THE TIMING OF THIS WAVE AND IS STRONGER THAN PREVIOUS RUNS NOW. THE TROUGH AXIS CROSSES SOUTH CENTRAL MONTANA AROUND 12Z WEDNESDAY. WILL HAVE SCATTERED SHOWERS WITH A FEW THUNDERSTORMS AHEAD OF THE WAVE TUESDAY OVER WESTERN AND CENTRAL ZONES. THE PRECIPITATION WILL SPREAD INTO THE EAST TUESDAY NIGHT. THE PATTERN THEN HOLDS INTO A ZONAL TO SLIGHTLY NORTHWEST FLOW FOR WEDNESDAY THROUGH FRIDAY. THIS LOOKS A LITTLE COOLER THAN PREVIOUS RUNS AS THE RIDGE PROGGED EARLIER IS FLATTENED DOWN QUITE A BIT AND THERE SHOULD BE MORE MID LEVEL CLOUDS AROUND. LOWERED HIGHS THROUGH THE PERIOD. MOST OF THE ENERGY STAYS NORTH OF THE AREA BUT CAN NOT RULE OUT CONVECTION CHANCES AS THERE IS NOT MUCH AMPLIFICATION TO THE RIDGE ANYMORE. A STRONG TROUGH WILL INVADE THE PACIFIC NORTHWEST SATURDAY AND THIS WILL PROVIDE A BETTER CHANCE OF SHOWERS FOR NEXT WEEKEND. TWH && .AVIATION... SCATTERED SHOWERS WILL BE ACCOMPANIED BY MVFR CONDITIONS TONIGHT THROUGH MON MORNING. SHOWERS WILL BECOME WIDELY SCATTERED MON AFTERNOON WITH POSSIBLE MVFR CONDITIONS. EXPECT GUSTY W TO NW WINDS ON MON...MAINLY FROM KBIL E AND S...AND OVER KLVM. WINDS WILL BE 20 TO 30 KT AND GUSTY. EXPECT WIDESPREAD MOUNTAIN OBSCURATIONS TONIGHT AND AREAS OF OBSCURATION ON MON. ARTHUR && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 038/061 042/067 045/066 047/072 051/078 054/080 054/071 32/W 13/T 32/T 11/B 21/B 12/T 22/W LVM 036/059 036/065 036/063 040/069 043/074 046/077 046/068 53/W 14/T 32/T 12/T 22/W 22/T 22/W HDN 039/063 042/070 045/068 046/074 050/080 053/083 054/075 42/W 12/T 32/T 11/B 21/B 12/T 22/W MLS 038/057 039/066 045/064 047/071 050/077 054/082 055/073 43/W 11/B 42/T 22/T 11/B 12/T 22/W 4BQ 037/057 040/063 046/065 045/071 049/077 053/082 054/074 42/W 11/B 43/T 12/T 11/B 12/T 22/W BHK 036/050 037/060 041/061 044/068 049/075 053/080 055/074 43/W 11/B 44/T 22/T 11/B 12/T 22/W SHR 036/059 037/068 044/063 043/069 046/075 050/079 050/074 32/W 12/T 32/T 11/B 21/B 12/T 22/W && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
845 PM MDT SUN MAY 27 2012 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... UPDATED THE FORECAST TONIGHT TO MORE ACCURATELY REPRESENT THE POPS AS RADAR REFLECTIVITIES AND HRRR MODEL RUNS SHOW THE SCATTERED RAIN SHOWERS SPIRALING THROUGH PARTS OF OUR CWA...LESS SO BEFORE MIDNIGHT AND MORE SO AFTER MIDNIGHT...ESPECIALLY OVER OUR EASTERN ZONES. SOME OF OUR HIGHER ELEVATION AREAS IN THE NORTH AND WEST WILL PROBABLY SEE A RAIN AND SNOW MIX TONIGHT. KEPT THE WINTER WEATHER ADVISORY FOR THE LITTLE ROCKIES AND EXPECT ACCUMULATIONS AROUND 4 INCHES NEAR AND ABOVE THE ZORTMAN MINE. OTHERWISE...ADJUSTMENTS WERE SMALL. BMICKELSON PREVIOUS SHORT TERM DISCUSSION...THE STORM SYSTEM LOW PRESSURE CENTER MOVES ON TOP OF NORTHEAST MONTANA TONIGHT. WHILE THE MAIN PRECIPITATION BAND WILL HAVE MOVED INTO CANADA...THE STORM CORE WILL KEEP SHOWERS CONTINUING TONIGHT AND MONDAY AS IT MOVES INTO NORTH DAKOTA. THIS STORM EFFICIENTLY PRODUCED SNOW OVER CENTRAL MONTANA AND AREAS IN OUR WEST TODAY. THIS AFTERNOON ZORTMAN IS STILL REPORTING SNOW FALLING. MODELS SHOW 850MB TEMPERATURES OF 0C TO -2C FOR TONIGHT. THEREFORE WILL CONTINUE TO MENTION SNOW AND KEEP SW PHILLIPS CO IN A SNOW ADVISORY. HEAVIEST QPF FOR TONIGHT WILL BE ALONG OUR WESTERN AND NORTHERN CWA BORDERS. ALTHOUGH WINDS OVER FORT PECK LAKE HAVEN`T BEEN THAT STRONG TODAY...WINDS ARE EXPECTED TO PICK UP AGAIN TONIGHT AND ESPECIALLY MONDAY. SO WILL LEAVE NPW FOR FORT PECK LAKE IN PLACE. ANOTHER CONCERN IS THE AMOUNT OF RAIN RECEIVED SINCE SATURDAY. SPOTTER REPORTS AVERAGE AROUND 1.25 INCH OF RAIN OVER MUCH OF THE AREA...WITH A SINGLE REPORT OF 2.4 INCH IN PHILLIPS CO. THE GROUND WAS ON THE DRY SIDE SO EXPECT MUCH OF THE RAIN WAS ABSORBED BY THE GROUND SINCE THE RAIN WAS MOSTLY LIGHT AND STEADY. HAVE HAD REPORTS OF THE CREEKS RUNNING...BUT NO REPORTS OF FLOODING. WILL CONTINUE TO MONITOR HYDRO. MONDAY NIGHT/TUESDAY...SHOWERS END AS NW FLOW ALOFT BRINGS IN DRY AIR...STILL ON THE COOL SIDE MONDAY NIGHT. TUESDAY WILL SEE A NARROW RIDGE THAT WILL TEND TO WARM TEMPERATURES CLOSER TO NORMAL. HOWEVER LATE IN THE DAY AN UPPER SHORTWAVE DISTURBANCE SENDS SHOWERS AND POSSIBLY THUNDERSTORMS INTO CENTRAL MONTANA AND OUR FAR WESTERN ZONES. SCT .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... THE EXTENDED FORECAST PERIOD BEGINS WITH A SMALL UPPER LEVEL DISTURBANCE SLIDING THROUGH AN OTHERWISE MOSTLY ZONAL WEATHER PATTERN OVER THE NORTHERN ROCKIES AND NORTHERN HIGH PLAINS. THIS QUICK MOVING SHORT WAVE WILL PROBABLY BRING SOME RAIN SHOWERS TO PORTIONS OF THE CWA. WEDNESDAY NIGHT THROUGH FRIDAY...THE CWA COMES UNDER NORTHWEST FLOW ALOFT AS WEAK RIDGING SLOWLY BUILDS IN FROM THE WEST AND ALLOWS TEMPERATURES TO CLIMB ABOVE NORMAL VALUES. ENOUGH INSTABILITY AND MOISTURE MAY STILL BE PRESENT TO SET OFF SOME AFTERNOON SHOWERS AND THUNDERSTORMS...SO KEPT SOME WET POPS IN THERE MOST DAYS. FRIDAY NIGHT THROUGH SATURDAY NIGHT...MAIN RIDGE AXIS MOVES OVER THE REGION AND DROPS POPS DOWN TO SILENT MAINLY. SUNDAY AND BEYOND...ANOTHER LONG WAVE UPPER LEVEL TROUGH SPILLS INTO THE NORTHERN ROCKIES FROM THE PACIFIC NORTHWEST. EXTENDED MODELS ARE IN FAIR AGREEMENT THROUGHOUT. TRIED TO INCREASE POPS WHERE I NOTICED THESE CONSISTENCIES. BMICKELSON && .AVIATION... RAIN WITH OVERCAST CEILINGS 1-2K FT AGL ACROSS ROUGHLY THE W 2/3 OF THE FORECAST AREA THIS EVENING. THIS WILL EXPAND INTO THE E THIRD OF THE FORECAST AREA...INCLUDING TAF SITES SDY AND GDV AROUND MIDNIGHT. EXPECT VISIBILITIES MAINLY 5 TO 7 MILES IN THE RAIN...BUT MAY BRIEFLY LOWER TO 3 TO 5 MILES. THE RAIN WILL MIX WITH SNOW IN PLACES BY 12Z BEFORE THE RAIN AND SNOW ENDS LATER IN THE MORNING. OVERCAST MVFR CEILINGS CONTINUE THRU MOST OF THE AFTERNOON MONDAY...RISING TO AROUND 3K FT AGL LATE AFTERNOON. W TO NW WINDS 20 TO 30 KT FOR MOST OF THE DAY TOO. SIMONSEN && .CLIMATE... MAY WILL PROBABLY END UP SLIGHTLY COOLER THAN NORMAL IN GLASGOW... ENDING A STREAK OF 10 MONTHS IN A ROW THAT HAVE BEEN WARMER THAN NORMAL. THIS REFLECTS A CONTINUED TREND OF COOLER AND WETTER THAN NORMAL MAYS IN RECENT YEARS. MAY 2012 WILL MARK 6 OF THE PAST 7 MAYS AS BEING COOLER THAN NORMAL...WHILE 9 OF THE LAST 11 MAYS HAVE ALSO BEEN WETTER THAN NORMAL. SIMONSEN && .GLASGOW WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 AM MDT MONDAY FOR SOUTHWEST PHILLIPS. LAKE WIND ADVISORY UNTIL 9 PM MDT MONDAY FOR FORT PECK LAKE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
811 PM CDT SUN MAY 27 2012 .UPDATE...WINDS HAVE DIMINISHED WITH THE EXCEPTION OF NEAR THUNDERSTORMS. HAVE LET THE WIND ADVISORY EXPIRE. THE REMAINDER OF THE FORECAST IS IN GOOD SHAPE AT THIS TIME. && .PREV DISCUSSION... /ISSUED 616 PM CDT SUN MAY 27 2012/ AVIATION...00Z TAF. MAIN INTEREST WILL BE THUNDERSTORMS EARLY IN THE PERIOD. A LINE TO THUNDERSTORMS IS DEVELOPING TO THE WEST OF THE KGRI TERMINAL AREA NEAR A COLD FRONT. THE THUNDERSTORMS WILL BE MOVING THROUGH THE KGRI TERMINAL AREA OVER THE NEXT FEW HOURS. THERE IS A CHANCE FOR SOME LATER AFTER THE LINE OF STORMS MOVE THROUGH...BUT IT SHOULD BE MORE SPOTTY AFTER THE FRONT MOVES THROUGH. WITH THE FRONT WINDS WILL TURN TO THE NORTHWEST. LATE TONIGHT THE THUNDERSTORMS SHOULD COME TO AN END AND THE SKIES SHOULD START TO CLEAR OUT. PREV DISCUSSION... /ISSUED 324 PM CDT SUN MAY 27 2012/ SHORT TERM...THIS AFTERNOON THROUGH MONDAY. OVERALL VERY LITTLE NOTABLE CHANGE TO THE INHERITED FORECAST THROUGH THE NEXT 24-30 HOURS...WITH THE OBVIOUS MAIN ISSUE BEING THE LIKELY ROUND OF SEVERE THUNDERSTORMS/HEAVY RAINFALL LATE THIS AFTERNOON INTO TONIGHT. 18Z OBJECTIVE SURFACE ANALYSIS PAINTS A WEAK 1002 MB LOW NEAR HILL CITY KS...WITH A SOMEWHAT ILL-DEFINED COLD FRONT EXTENDING NORTH FROM THE LOW ACROSS FAR WEST/NORTHWEST PORTIONS OF THE CWA. FARTHER EAST...THE MAJORITY OF THE CWA IS SOLIDLY IN THE SOUTHERLY WIND REGIME AHEAD OF THE BOUNDARY...WITH SUSTAINED SPEEDS MAINLY 15-25 MPH AND GUSTS UP TO 35 MPH. HOWEVER...KS ZONES ARE AVERAGING A BIT STRONGER SPEEDS...WITH SUSTAINED CLOSER TO 30 MPH AND GUSTS TO AROUND 40 MPH. ALTHOUGH WINDS ARE CURRENTLY STRUGGLING TO REACH ADVISORY CRITERIA DOWN THERE...ANTICIPATE A POSSIBLE SLIGHT INCREASE AS THE AFTERNOON WEARS ON...AND THUS WILL LET THE INHERITED WIND ADVISORY CONTINUE AS-IS FOR NOW ALTHOUGH AN EARLY CANCELLATION IS NOT OUT OF THE QUESTION. TEMP WISE...EARLIER NUDGED UP AFTERNOON HIGHS 1-2 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...RANGING FROM MID 80S WEST TO LOW 90S EAST AND SOUTH. SO FAR...THIS SEEMS TO BE ON TRACK...DESPITE THE FAIRLY WIDESPREAD CUMULUS FIELD WHICH AS OVERTAKEN MOST OF THE CWA. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY REVEALS THE PRIMARY EXPANSIVE SHORTWAVE OF INTEREST APPROACHING FROM THE CENTRAL PLAINS...AND ANCHORED BY A CLOSED 500MB LOW PUSHING ACROSS EASTERN MT. THE PRIMARY 300MB JET AXIS AROUND 100KT IS STILL TO THE WEST...EXTENDING NORTH-SOUTH FROM WESTERN NEB INTO SD. RADAR WISE...THERE HAVE BEEN A SMATTERING OF HIGH BASED SHOWERS/MAYBE A FEW VERY WEAK THUNDERSTORMS MIGRATING NORTHEAST ACROSS CENTRAL/EASTERN COUNTIES DURING THE PAST SEVERAL HOURS...LIKELY AMOUNTING TO NOTHING MORE THAN A GLORIFIED SPRINKLE. GETTING TO THE FORECAST...THE WELL-ADVERTISED AFTERNOON/EVENING ROUND OF SEVERE THUNDERSTORMS IS THE PARAMOUNT CONCERN. LITTLE CHANGE IN THINKING/MODEL TRENDS HAS OCCURRED THUS FAR FROM THE INHERITED OVERNIGHT FORECAST...WHICH REALLY SEEMED TO HAVE A GOOD HANDLE ON THINGS. ALSO AGREE WITH LATEST SPC DAY 1 CONVECTIVE OUTLOOK EMPHASIZING THE HAIL/WIND THREAT BUT KEEPING THE TORNADO POTENTIAL MORE IN CHECK. ONE TREND THAT HAS SEEMED TO EMERGE TODAY IS SLIGHTLY LOWER INSTABILITY VALUES...WITH THE RAP/RUC ADVERTISING 0-1 KM MLCAPE VALUES TOPPING OUT MAINLY AROUND 1500 J/KG INSTEAD OF MORE WIDESPREAD 2000 J/KG. HOWEVER...WITH 0-6KM DEEP LAYER SHEAR VALUES CURRENTLY INCREASING INTO THE 40-60KT RANGE FROM WEST TO EAST AS THE SHORTWAVE APPROACHES...AND MID LEVEL TEMPS GRADUALLY COOLING AS WELL...SHOULD STILL SEE A ROBUST SEVERE THREAT. LEANING TOWARD THE LATEST RAP/RUC AND HRRR FOR THE DETAILS...THE 21Z-00Z TIME FRAME SHOULD FEATURE THE ONSET OF STRONG/SEVERE CONVECTION...MAINLY ACROSS THE WESTERN 1/2 OF THE CWA. AS A RESULT...LOWERED POPS A BIT IN EASTERN ZONES THROUGH 00Z...KEEPING SEVERAL COUNTIES BELOW LIKELY WORDING. ONCE STORMS FORM...A POTENTIALLY MESSY MIX OF INITIALLY DISCRETE CELLS AND QUASI-LINEAR SEGMENTS SHOULD UNFOLD...WITH INDIVIDUAL ELEMENTS TRACKING NORTHEAST AROUND 35 MPH. WITH SURFACE DEWPOINT DEPRESSIONS ON THE ORDER OF 20-30 DEGREES...AND RESULTANT LCL HEIGHTS LARGELY IN EXCESS OF 1500-2000M TO START OUT WITH...THINK THAT INITIAL STORMS SHOULD BE MAINLY HAIL/EFFICIENT WIND PRODUCERS...POSSIBLY PRODUCING ANOTHER ROUND OF GUSTNADOES AS SEEN BACK ON THE 19TH. HOWEVER...AS LONG AS STORMS CAN REMAIN AT LEAST QUASI-DISCRETE TOWARD 00Z AND TOWARD SUNSET...PARAMETERS DO BECOME A BIT MORE FAVORABLE FOR MAYBE A FEW TORNADOES...WITH BOUNDARY LAYER COOLING BRINGING LCLS DOWN CLOSER TO 1000M AND 0-1KM BULK SHEAR INCREASING TO AROUND 20-25KT AND 0-1KM SRH POSSIBLY EXCEEDING 150 M2/S2...AT LEAST FOR A FEW HOURS. THIS IS PARTIALLY IN RESPONSE TO SURFACE WINDS SLIGHTLY BACKING IN RESPONSE TO THE LOW DEEPENING A BIT TO AROUND 997MB IN NORTHWEST/NORTH CENTRAL KS. FOR TORNADO POTENTIAL...SO MUCH WILL DEPEND ON YET-TO-BE-RESOLVED DETAILS IN STORM MODE/STORM INTERACTION...BUT OVERALL THE ENVIRONMENT SHOULD NOT SUPPORT ANYTHING LONG TRACK OR PARTICULARLY STRONG. AS FOR HAIL...WILL LEAVE POTENTIAL FOR UP TO BASEBALL WORDING IN THE HWO...BUT WITH INSTABILITY NOT EYE-POPPING WOULD TEND TO THINK MOST SHOULD REMAIN GOLF BALL OR SMALLER. CERTAINLY WIND GUSTS TO AT LEAST 70 MPH ARE A CONCERN. SPECIFICALLY GETTING INTO THE EVENING 00Z-06Z PERIOD...KEPT 60-80 POPS GOING ACROSS MAINLY THE EASTERN HALF OF THE CWA...BUT EXPANDED AT LEAST SLIGHT POPS ALL THE WAY BACK ACROSS THE FAR WEST...AS THE COLD FRONTAL INVASION APPEARS TO BE A BIT SLOWER THAN PREVIOUSLY THOUGHT...AS IT STALLS OUT IN RESPONSE TO A GRADUAL DEEPENING OF THE NORTHWEST KS SURFACE LOW TO AROUND 997MB. THAT BEING SAID...THERE WILL LIKELY STILL BE SHARP EAST-WEST GRADIENT BETWEEN STORMS AND NO STORMS...AND SEVERAL WESTERN COUNTIES COULD MISS OUT ON MOST IF NOT ALL THE ACTION. LOCALLY HEAVY RAIN POTENTIAL WILL INCREASE THIS EVENING AS WELL...AS STORMS LIKELY BECOME MORE LINEAR AND THE 850MB LOW LEVEL JET ACCELERATES MOISTURE TRANSPORT INTO AND OVER THE INVADING LOW LEVEL FRONTAL ZONE. SHOULD EASILY SEE SOME FAIRLY WIDESPREAD 1-2 INCH AMOUNTS...WITH LOCALIZED 2+ QUITE POSSIBLE AS WELL IF THINGS STALL OUT AND/OR BACKBUILD FOR A FEW HOURS THIS EVENING AS HINTED BY THE 12Z 4KM WRF-NMM EXPLICIT REFLECTIVITY. FOR THE LATE NIGHT 06Z-12Z PERIOD...MAIN CHANGE WAS TO INCREASE POPS ACROSS EASTERN ZONES DURING THE 06Z-09Z PERIOD...BUT KEPT THEM BELOW LIKELY RANGE AT LEAST FOR NOW. BOTH THE 12Z NAM/4KM WRF SUPPORT LINGERING CONVECTION FOR AT LEAST A FEW HOURS PAST 06Z ESPECIALLY IN SOUTHEAST COUNTIES. CONFIDENCE IS RATHER HIGH IN STORM-FREE CONDITIONS POST-09Z...AS DRIER AIR INVADES BEHIND THE PASSING COLD FRONT. KEPT LOW TEMPS TONIGHT SIMILAR TO PREVIOUS...RANGING FROM LOW 50S FAR WEST TO LOW 60S FAR EAST. GETTING INTO MONDAY...OTHER THAN BEING A BIT BREEZY...A PLEASANT MEMORIAL DAY HOLIDAY IS IN STORE. ALOFT...THE PARENT 500MB CLOSED LOW WILL SLOWLY MIGRATE FROM THE MT/ND BORDER TO EASTERN ND...WHILE AT THE SURFACE...THE COLD FRONT TRACKS WELL OFF TO THE SOUTH AND EAST...ALIGNED FROM NORTHERN IL TO NEAR THE KS/OK BORDER BY LATE AFTERNOON. MUCH DRIER AND SOMEWHAT COOLER AIR WILL ARRIVE IN THE WAKE OF THIS BOUNDARY...RESULTING IN SUNNY/MOSTLY SUNNY SKIES. CHANGED HIGH TEMPS LITTLE FROM PREVIOUS FORECAST...KEEPING THEM CLOSE TO 12Z MET GUIDANCE RANGING FROM MID-UPPER 70S NORTHWEST TO MAINLY MID 80S SOUTHEAST. HOWEVER FAR SOUTHEAST AROUND BELOIT COULD STILL REACH UPPER 80S. LOWERED DEWPOINTS A FEW DEGREES FROM PREVIOUS FORECAST...AND POSSIBLY NOT ENOUGH...AS NAM-BASED MIX-DOWN TOOLS SUGGEST DEWPOINTS COULD PLUNGE ALL THE WAY INTO THE 20S IN SOUTH/WEST AREAS AS BOUNDARY LAYER MIXING INCREASES TO AROUND 700MB. NOT GOING TO GO QUITE THIS LOW YET...BUT STILL HAVE MOST OF THE CWA MIXING WELL DOWN INTO THE 30S FOR DEWPOINTS. FORTUNATELY WILL NOT HAVE TO CONSIDER A RED FLAG WARNING AS OFFICIAL VEGETATIVE FUEL STATUS IS STILL DEEMED UNFAVORABLE FOR FIRE GROWTH...BUT RH VALUES SHOULD NONETHELESS DIVE BELOW 20 PERCENT ACROSS AT LEAST THE SOUTHWEST 1/2 OF THE CWA. THE AFOREMENTIONED DEEP MIXING WILL ALSO KICK UP WESTERLY WINDS DURING THE DAY...WITH SUSTAINED SPEEDS EASILY 15-20 MPH FOR SEVERAL HOURS AND GUSTING TO AROUND 25 MPH. LONG TERM...MONDAY NIGHT THROUGH SUNDAY. MAIN FORECAST CONCERNS WILL BE THUNDERSTORM CHANCES AND TEMPERATURES. A SURFACE HIGH BUILDS INTO THE FORECAST AREA MONDAY NIGHT INTO TUESDAY. TEMPERATURES WILL BE A LITTLE COOLER AS THE TEMPERATURES AT 850MB DECREASE DURING THE DAY. BY TUESDAY NIGHT AN UPPER LEVEL WAVE STARTS TO MOVE INTO THE PLAINS. THIS WILL BRING A CHANCE FOR THUNDERSTORMS TO THE AREA. THE WAVE STRENGTHENS AS IT MOVES INTO THE AREA WEDNESDAY AND WEDNESDAY NIGHT. THE BEST CAPE IS GOING TO BE WEDNESDAY AFTERNOON AND DECREASES AFTER THAT. THERE COULD BE SOME STRONG THUNDERSTORMS DURING THE AFTERNOON BUT WITH THE CAPE DECREASING LATER...EXPECT THAT THUNDERSTORMS WILL BECOME MORE ISOLATED DURING THE EVENING. WITH CLOUDS AND PRECIPITATION AROUND ON WEDNESDAY EXPECT TEMPERATURES TO BE A BIT COOLER THAN RECENTLY. THE SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ON THURSDAY WHEN THE UPPER WAVE FINALLY MOVES TO THE EAST. TEMPERATURES WILL REMAIN ON THE COOLER SIDE FOR THURSDAY. THURSDAY NIGHT INTO FRIDAY WILL BE DOMINATED BY ANOTHER SURFACE HIGH PRESSURE AREA THAT SETTLES INTO THE AREA. BY FRIDAY NIGHT THE SURFACE HIGH MOVES OFF TO THE EAST AND WINDS TURN TO THE SOUTH. A COUPLE OF WEAK UPPER LEVEL WAVES MOVE INTO THE AREA FOR THE PERIOD SATURDAY INTO SUNDAY. EXPECT SOME SLIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WITH SPOTTY PRECIPITATION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
616 PM CDT SUN MAY 27 2012 .AVIATION...00Z TAF. MAIN INTEREST WILL BE THUNDERSTORMS EARLY IN THE PERIOD. A LINE TO THUNDERSTORMS IS DEVELOPING TO THE WEST OF THE KGRI TERMINAL AREA NEAR A COLD FRONT. THE THUNDERSTORMS WILL BE MOVING THROUGH THE KGRI TERMINAL AREA OVER THE NEXT FEW HOURS. THERE IS A CHANCE FOR SOME LATER AFTER THE LINE OF STORMS MOVE THROUGH...BUT IT SHOULD BE MORE SPOTTY AFTER THE FRONT MOVES THROUGH. WITH THE FRONT WINDS WILL TURN TO THE NORTHWEST. LATE TONIGHT THE THUNDERSTORMS SHOULD COME TO AN END AND THE SKIES SHOULD START TO CLEAR OUT. && .PREV DISCUSSION... /ISSUED 324 PM CDT SUN MAY 27 2012/ SHORT TERM...THIS AFTERNOON THROUGH MONDAY. OVERALL VERY LITTLE NOTABLE CHANGE TO THE INHERITED FORECAST THROUGH THE NEXT 24-30 HOURS...WITH THE OBVIOUS MAIN ISSUE BEING THE LIKELY ROUND OF SEVERE THUNDERSTORMS/HEAVY RAINFALL LATE THIS AFTERNOON INTO TONIGHT. 18Z OBJECTIVE SURFACE ANALYSIS PAINTS A WEAK 1002 MB LOW NEAR HILL CITY KS...WITH A SOMEWHAT ILL-DEFINED COLD FRONT EXTENDING NORTH FROM THE LOW ACROSS FAR WEST/NORTHWEST PORTIONS OF THE CWA. FARTHER EAST...THE MAJORITY OF THE CWA IS SOLIDLY IN THE SOUTHERLY WIND REGIME AHEAD OF THE BOUNDARY...WITH SUSTAINED SPEEDS MAINLY 15-25 MPH AND GUSTS UP TO 35 MPH. HOWEVER...KS ZONES ARE AVERAGING A BIT STRONGER SPEEDS...WITH SUSTAINED CLOSER TO 30 MPH AND GUSTS TO AROUND 40 MPH. ALTHOUGH WINDS ARE CURRENTLY STRUGGLING TO REACH ADVISORY CRITERIA DOWN THERE...ANTICIPATE A POSSIBLE SLIGHT INCREASE AS THE AFTERNOON WEARS ON...AND THUS WILL LET THE INHERITED WIND ADVISORY CONTINUE AS-IS FOR NOW ALTHOUGH AN EARLY CANCELLATION IS NOT OUT OF THE QUESTION. TEMP WISE...EARLIER NUDGED UP AFTERNOON HIGHS 1-2 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...RANGING FROM MID 80S WEST TO LOW 90S EAST AND SOUTH. SO FAR...THIS SEEMS TO BE ON TRACK...DESPITE THE FAIRLY WIDESPREAD CUMULUS FIELD WHICH AS OVERTAKEN MOST OF THE CWA. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY REVEALS THE PRIMARY EXPANSIVE SHORTWAVE OF INTEREST APPROACHING FROM THE CENTRAL PLAINS...AND ANCHORED BY A CLOSED 500MB LOW PUSHING ACROSS EASTERN MT. THE PRIMARY 300MB JET AXIS AROUND 100KT IS STILL TO THE WEST...EXTENDING NORTH-SOUTH FROM WESTERN NEB INTO SD. RADAR WISE...THERE HAVE BEEN A SMATTERING OF HIGH BASED SHOWERS/MAYBE A FEW VERY WEAK THUNDERSTORMS MIGRATING NORTHEAST ACROSS CENTRAL/EASTERN COUNTIES DURING THE PAST SEVERAL HOURS...LIKELY AMOUNTING TO NOTHING MORE THAN A GLORIFIED SPRINKLE. GETTING TO THE FORECAST...THE WELL-ADVERTISED AFTERNOON/EVENING ROUND OF SEVERE THUNDERSTORMS IS THE PARAMOUNT CONCERN. LITTLE CHANGE IN THINKING/MODEL TRENDS HAS OCCURRED THUS FAR FROM THE INHERITED OVERNIGHT FORECAST...WHICH REALLY SEEMED TO HAVE A GOOD HANDLE ON THINGS. ALSO AGREE WITH LATEST SPC DAY 1 CONVECTIVE OUTLOOK EMPHASIZING THE HAIL/WIND THREAT BUT KEEPING THE TORNADO POTENTIAL MORE IN CHECK. ONE TREND THAT HAS SEEMED TO EMERGE TODAY IS SLIGHTLY LOWER INSTABILITY VALUES...WITH THE RAP/RUC ADVERTISING 0-1 KM MLCAPE VALUES TOPPING OUT MAINLY AROUND 1500 J/KG INSTEAD OF MORE WIDESPREAD 2000 J/KG. HOWEVER...WITH 0-6KM DEEP LAYER SHEAR VALUES CURRENTLY INCREASING INTO THE 40-60KT RANGE FROM WEST TO EAST AS THE SHORTWAVE APPROACHES...AND MID LEVEL TEMPS GRADUALLY COOLING AS WELL...SHOULD STILL SEE A ROBUST SEVERE THREAT. LEANING TOWARD THE LATEST RAP/RUC AND HRRR FOR THE DETAILS...THE 21Z-00Z TIME FRAME SHOULD FEATURE THE ONSET OF STRONG/SEVERE CONVECTION...MAINLY ACROSS THE WESTERN 1/2 OF THE CWA. AS A RESULT...LOWERED POPS A BIT IN EASTERN ZONES THROUGH 00Z...KEEPING SEVERAL COUNTIES BELOW LIKELY WORDING. ONCE STORMS FORM...A POTENTIALLY MESSY MIX OF INITIALLY DISCRETE CELLS AND QUASI-LINEAR SEGMENTS SHOULD UNFOLD...WITH INDIVIDUAL ELEMENTS TRACKING NORTHEAST AROUND 35 MPH. WITH SURFACE DEWPOINT DEPRESSIONS ON THE ORDER OF 20-30 DEGREES...AND RESULTANT LCL HEIGHTS LARGELY IN EXCESS OF 1500-2000M TO START OUT WITH...THINK THAT INITIAL STORMS SHOULD BE MAINLY HAIL/EFFICIENT WIND PRODUCERS...POSSIBLY PRODUCING ANOTHER ROUND OF GUSTNADOES AS SEEN BACK ON THE 19TH. HOWEVER...AS LONG AS STORMS CAN REMAIN AT LEAST QUASI-DISCRETE TOWARD 00Z AND TOWARD SUNSET...PARAMETERS DO BECOME A BIT MORE FAVORABLE FOR MAYBE A FEW TORNADOES...WITH BOUNDARY LAYER COOLING BRINGING LCLS DOWN CLOSER TO 1000M AND 0-1KM BULK SHEAR INCREASING TO AROUND 20-25KT AND 0-1KM SRH POSSIBLY EXCEEDING 150 M2/S2...AT LEAST FOR A FEW HOURS. THIS IS PARTIALLY IN RESPONSE TO SURFACE WINDS SLIGHTLY BACKING IN RESPONSE TO THE LOW DEEPENING A BIT TO AROUND 997MB IN NORTHWEST/NORTH CENTRAL KS. FOR TORNADO POTENTIAL...SO MUCH WILL DEPEND ON YET-TO-BE-RESOLVED DETAILS IN STORM MODE/STORM INTERACTION...BUT OVERALL THE ENVIRONMENT SHOULD NOT SUPPORT ANYTHING LONG TRACK OR PARTICULARLY STRONG. AS FOR HAIL...WILL LEAVE POTENTIAL FOR UP TO BASEBALL WORDING IN THE HWO...BUT WITH INSTABILITY NOT EYE-POPPING WOULD TEND TO THINK MOST SHOULD REMAIN GOLF BALL OR SMALLER. CERTAINLY WIND GUSTS TO AT LEAST 70 MPH ARE A CONCERN. SPECIFICALLY GETTING INTO THE EVENING 00Z-06Z PERIOD...KEPT 60-80 POPS GOING ACROSS MAINLY THE EASTERN HALF OF THE CWA...BUT EXPANDED AT LEAST SLIGHT POPS ALL THE WAY BACK ACROSS THE FAR WEST...AS THE COLD FRONTAL INVASION APPEARS TO BE A BIT SLOWER THAN PREVIOUSLY THOUGHT...AS IT STALLS OUT IN RESPONSE TO A GRADUAL DEEPENING OF THE NORTHWEST KS SURFACE LOW TO AROUND 997MB. THAT BEING SAID...THERE WILL LIKELY STILL BE SHARP EAST-WEST GRADIENT BETWEEN STORMS AND NO STORMS...AND SEVERAL WESTERN COUNTIES COULD MISS OUT ON MOST IF NOT ALL THE ACTION. LOCALLY HEAVY RAIN POTENTIAL WILL INCREASE THIS EVENING AS WELL...AS STORMS LIKELY BECOME MORE LINEAR AND THE 850MB LOW LEVEL JET ACCELERATES MOISTURE TRANSPORT INTO AND OVER THE INVADING LOW LEVEL FRONTAL ZONE. SHOULD EASILY SEE SOME FAIRLY WIDESPREAD 1-2 INCH AMOUNTS...WITH LOCALIZED 2+ QUITE POSSIBLE AS WELL IF THINGS STALL OUT AND/OR BACKBUILD FOR A FEW HOURS THIS EVENING AS HINTED BY THE 12Z 4KM WRF-NMM EXPLICIT REFLECTIVITY. FOR THE LATE NIGHT 06Z-12Z PERIOD...MAIN CHANGE WAS TO INCREASE POPS ACROSS EASTERN ZONES DURING THE 06Z-09Z PERIOD...BUT KEPT THEM BELOW LIKELY RANGE AT LEAST FOR NOW. BOTH THE 12Z NAM/4KM WRF SUPPORT LINGERING CONVECTION FOR AT LEAST A FEW HOURS PAST 06Z ESPECIALLY IN SOUTHEAST COUNTIES. CONFIDENCE IS RATHER HIGH IN STORM-FREE CONDITIONS POST-09Z...AS DRIER AIR INVADES BEHIND THE PASSING COLD FRONT. KEPT LOW TEMPS TONIGHT SIMILAR TO PREVIOUS...RANGING FROM LOW 50S FAR WEST TO LOW 60S FAR EAST. GETTING INTO MONDAY...OTHER THAN BEING A BIT BREEZY...A PLEASANT MEMORIAL DAY HOLIDAY IS IN STORE. ALOFT...THE PARENT 500MB CLOSED LOW WILL SLOWLY MIGRATE FROM THE MT/ND BORDER TO EASTERN ND...WHILE AT THE SURFACE...THE COLD FRONT TRACKS WELL OFF TO THE SOUTH AND EAST...ALIGNED FROM NORTHERN IL TO NEAR THE KS/OK BORDER BY LATE AFTERNOON. MUCH DRIER AND SOMEWHAT COOLER AIR WILL ARRIVE IN THE WAKE OF THIS BOUNDARY...RESULTING IN SUNNY/MOSTLY SUNNY SKIES. CHANGED HIGH TEMPS LITTLE FROM PREVIOUS FORECAST...KEEPING THEM CLOSE TO 12Z MET GUIDANCE RANGING FROM MID-UPPER 70S NORTHWEST TO MAINLY MID 80S SOUTHEAST. HOWEVER FAR SOUTHEAST AROUND BELOIT COULD STILL REACH UPPER 80S. LOWERED DEWPOINTS A FEW DEGREES FROM PREVIOUS FORECAST...AND POSSIBLY NOT ENOUGH...AS NAM-BASED MIX-DOWN TOOLS SUGGEST DEWPOINTS COULD PLUNGE ALL THE WAY INTO THE 20S IN SOUTH/WEST AREAS AS BOUNDARY LAYER MIXING INCREASES TO AROUND 700MB. NOT GOING TO GO QUITE THIS LOW YET...BUT STILL HAVE MOST OF THE CWA MIXING WELL DOWN INTO THE 30S FOR DEWPOINTS. FORTUNATELY WILL NOT HAVE TO CONSIDER A RED FLAG WARNING AS OFFICIAL VEGETATIVE FUEL STATUS IS STILL DEEMED UNFAVORABLE FOR FIRE GROWTH...BUT RH VALUES SHOULD NONETHELESS DIVE BELOW 20 PERCENT ACROSS AT LEAST THE SOUTHWEST 1/2 OF THE CWA. THE AFOREMENTIONED DEEP MIXING WILL ALSO KICK UP WESTERLY WINDS DURING THE DAY...WITH SUSTAINED SPEEDS EASILY 15-20 MPH FOR SEVERAL HOURS AND GUSTING TO AROUND 25 MPH. LONG TERM...MONDAY NIGHT THROUGH SUNDAY. MAIN FORECAST CONCERNS WILL BE THUNDERSTORM CHANCES AND TEMPERATURES. A SURFACE HIGH BUILDS INTO THE FORECAST AREA MONDAY NIGHT INTO TUESDAY. TEMPERATURES WILL BE A LITTLE COOLER AS THE TEMPERATURES AT 850MB DECREASE DURING THE DAY. BY TUESDAY NIGHT AN UPPER LEVEL WAVE STARTS TO MOVE INTO THE PLAINS. THIS WILL BRING A CHANCE FOR THUNDERSTORMS TO THE AREA. THE WAVE STRENGTHENS AS IT MOVES INTO THE AREA WEDNESDAY AND WEDNESDAY NIGHT. THE BEST CAPE IS GOING TO BE WEDNESDAY AFTERNOON AND DECREASES AFTER THAT. THERE COULD BE SOME STRONG THUNDERSTORMS DURING THE AFTERNOON BUT WITH THE CAPE DECREASING LATER...EXPECT THAT THUNDERSTORMS WILL BECOME MORE ISOLATED DURING THE EVENING. WITH CLOUDS AND PRECIPITATION AROUND ON WEDNESDAY EXPECT TEMPERATURES TO BE A BIT COOLER THAN RECENTLY. THE SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ON THURSDAY WHEN THE UPPER WAVE FINALLY MOVES TO THE EAST. TEMPERATURES WILL REMAIN ON THE COOLER SIDE FOR THURSDAY. THURSDAY NIGHT INTO FRIDAY WILL BE DOMINATED BY ANOTHER SURFACE HIGH PRESSURE AREA THAT SETTLES INTO THE AREA. BY FRIDAY NIGHT THE SURFACE HIGH MOVES OFF TO THE EAST AND WINDS TURN TO THE SOUTH. A COUPLE OF WEAK UPPER LEVEL WAVES MOVE INTO THE AREA FOR THE PERIOD SATURDAY INTO SUNDAY. EXPECT SOME SLIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WITH SPOTTY PRECIPITATION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...WIND ADVISORY UNTIL 8 PM CDT THIS EVENING FOR KSZ006-007-017>019. && $$
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1134 PM EDT SUN MAY 27 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH ACROSS THE REGION TONIGHT SETTING THE STAGE FOR A HOT AND SULTRY MEMORIAL DAY. THE FRONT COULD ALSO HELP TO KICK OFF SOME BENEFICIAL SHOWERS AND THUNDERSTORMS. THE WARMTH WILL EASE ON TUESDAY AS A COLD FRONT WILL MOVE THROUGH THEN TEMPERATURES WILL ACTUALLY DROP TO BELOW NORMAL LEVELS FOR MUCH OF THE REST OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... A WARM FRONT LOCATED ACROSS CENTRAL PENNSYLVANIA WILL SLOWLY LIFT NORTHWARD OVERNIGHT. THE 00Z HRRR MODEL ONLY SHOWS SOME CONVECTION MOVING ACROSS NORTHERN NY AFTER 10Z. WHILE THE 00Z NAM SHOWS SOME CONVECTION MOVING ACROSS WESTERN NY NEAR 12Z MONDAY TRIGGERED BY AN UPPER LEVEL DISTURBANCE ROTATING THOUGH THE 500 MB FLOW. CONFIDENCE AT THIS TIME IS TO LOW TO INCLUDE IN GRIDS BUT WILL NEED TO MONITOR IR SATELLITE/RADAR OVERNIGHT. MODELS HAVE NOT HANDLED CONVECTIVE TRENDS VERY WELL OF LATE. WARM FRONT WILL HAVE CLEARED MUCH OF THE AREA MONDAY WITH A HOT AIR MASS MOVING INTO THE REGION. THE 00Z KBUF OBSERVED SOUNDING SHOWED +11C AT 700MB WHICH INDICATED A STRONG MID-LEVEL CAP. FEEL CONVECTIVE ACTIVITY MONDAY WILL BE CONFINED TO ALONG THE FRONT WHERE SOME LOW LEVEL CONVERGENCE COULD POP UP A SHOWER. MEMORIAL DAY TEMPERATURES WILL BE QUITE WARM WITH MOST HIGHS IN THE UPPER 80S TO LOWER 90S. SOME HEAT INDEX VALUES COULD POSSIBLY APPROACH 100F ESPECIALLY THOUGH SOME OF THE SOUTHERN TIER AND GENESEE RIVER VALLEYS. THERE WILL BE SOME RELIEF DUE TO THE SOUTHWEST GRADIENT THAT WILL DEVELOP BY AFTERNOON. RECORD HIGHS AT BUFFALO 86F/1987 AND ROCHESTER 93F/1911 WILL CERTAINLY BE CHALLENGED. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... A VERY WARM AND MUGGY AIRMASS WILL REMAIN ACROSS THE REGION MONDAY NIGHT WITH MANY AREAS NOT FALLING BELOW 70F. GIVEN THE WARMTH...INSTABILITY AND A 40 KNOT LOW LEVEL JET DURING THE OVERNIGHT...SHOWERS AND THUNDERSTORMS ARE POSSIBLE THROUGH THE OVERNIGHT HOURS. EXPECT ANOTHER WARM DAY ON TUESDAY WITH AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE DAY. ALTHOUGH DIFFICULT TO TIME...THE GFS IS DEPICTING A SERIES OF VORTICITY MAXIMA IN A SOUTHWESTERN UPPER FLOW AS THE UPPER RIDGE AXIS PASSES WELL EAST OF OUR AREA. WILL HAVE POPS IN THE LIKELY RANGE FOR MOST AREAS TUESDAY AFTERNOON AND EARLY EVENING. GFS AND ECMWF BOT SHOW THE BULK OF THE PRECIP TO BE AHEAD OF AN APPROACHING COLD FRONT...TO ARRIVE LATER ON TUESDAY NIGHT. TUESDAY NIGHT WILL BE A TIME OF GREATER CHANGES IN THE UPPER FLOW. A BROAD AND DEEP UPPER TROUGH ACROSS ONTARIO AND WESTERN QUEBEC PROVINCES TO THE GREAT LAKES WILL USHER IN A STRONG COLD FRONT WITH TEMPS FALLING BACK TO A MORE COMFORTABLE NIGHTTIME RANGE IN THE MID TO UPPER 50S. A SECONDARY FRONT AND UPPER VORTICITY MAX REMAIN JUST NORTH OF THE REGION ON WEDNESDAY WITH A WEAK NOSE OF HIGH PRESSURE EDGING INTO THE REGION FROM THE WEST. MOST MODEL GUIDANCE SHOWS ONLY SLIGHT CHANCE POPS. HIGH TEMPS ON WEDNESDAY TO BE IN THE UPPER TO LOWER 70S. EXPECT LOWS WEDNESDAY NIGHT IN THE UPPER 40S TO LOW 50S...SOME MID 40S ACROSS THE SOUTHERN TIER. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY AND FRIDAY WILL BE THE COOLEST DAYS OF THE WEEK WITH 850MB TEMPS RANGING FROM +3C TO +4C AND AFTERNOON HIGHS IN THE 60S FOLLOWED BY OVERNIGHT LOWS IN THE MID 40S TO LOW 50S. GFS AND ECMWF IN AGREEMENT WITH THE FORMATION OF A CUTOFF LOW ON FRIDAY AND HIGHER LIKELIHOOD OF RAIN ON FRIDAY AND FRIDAY NIGHT WITH TRAILING CHANCE POPS FOR SATURDAY. HIGH PRESSURE RIDGING NORTHWARD FROM THE SOUTHEASTERN STATES BRINGS A RETURN OF WARMER AIR ON SUNDAY WITH HIGHS BACK IN THE LOW TO MID 70S. && .AVIATION /04Z MONDAY THROUGH FRIDAY/... MAINLY VFR CONDITIONS WITH MID LEVEL CIGS EXCEPT FOR KJHW WHICH RECENTLY IS REPORTING SOME MVFR FOG AS A RESULT OF SOME SHOWERS EARLIER TODAY. WINDS AT ALL SITES WILL BE LIGHT AND VARIABLE OVERNIGHT. LATEST 00Z MODELS SHOWING A MIX OF SOLUTIONS WITH REGARD TO OVERNIGHT/MONDAY MORNING CONVECTION MOVING ACROSS THE FORECAST AREA. CONFIDENCE AT THIS TIME IS TO LOW TO INCLUDE IN ANY TAFS BUT WILL NEED TO MONITOR IR SATELLITE/RADAR OVERNIGHT. WARM FRONT WILL LIFT ACROSS THE REGION BY MONDAY MORNING WITH A RIDGE OF WARM AIR ALOFT KEEPING CONVECTION CAPPED WITH VFR. WINDS PICKING UP OUT OF THE SOUTHWEST BY LATE MORNING. OUTLOOK... TUESDAY...AREAS OF MVFR IN SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTH WINDS WINDS HAVE PICKED UP THIS EVENING AHEAD OF A WARM FRONT ALONG THE EASTERN END OF LAKE ERIE AND SOUTHWESTERN END OF LAKE ONTARIO. OTHERWISE PRETTY FAIR CONDITIONS ELSEWHERE. SOUTHWEST WINDS WILL INCREASE MONDAY...BUT DUE TO THE HOT AIR MASS ADVECTING INTO THE REGION THE OVER WATER STABILITY WILL LIMIT WIND SPEEDS AND PARTICULARLY WAVE HEIGHTS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH/TMA NEAR TERM...SMITH/TMA SHORT TERM...WCH LONG TERM...WCH AVIATION...SMITH MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1010 PM EDT SUN MAY 27 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH ACROSS THE REGION TONIGHT SETTING THE STAGE FOR A HOT AND SULTRY MEMORIAL DAY. THE FRONT COULD ALSO HELP TO KICK OFF SOME BENEFICIAL SHOWERS AND THUNDERSTORMS. THE WARMTH WILL EASE ON TUESDAY AS A COLD FRONT WILL MOVE THROUGH THEN TEMPERATURES WILL ACTUALLY DROP TO BELOW NORMAL LEVELS FOR MUCH OF THE REST OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... A WARM FRONT LOCATED ACROSS SOUTHERN PENNSYLVANIA WILL SLOWLY LIFT NORTHWARD OVERNIGHT. 12Z MODELS SHOWED THE POTENTIAL FOR A WIDESPREAD COVERAGE OF NOCTURNAL CONVECTION TO DEVELOP ALONG THE NOSE OF DEEP MOISTURE TRANSPORT...WITHIN A HIGH MOISTURE RIBBON OF 850 MB THETA E NORTH OF THE FRONTAL ZONE. HOWEVER THE 21Z HRRR MODEL DOES NOT SHOW ANYTHING FORMING OVERNIGHT. MODELS HAVE NOT HANDLED CONVECTIVE TRENDS VERY WELL OF LATE AND HAVE LOW CONFIDENCE FOR ANY ACTIVITY FORMING OVERNIGHT. UPDATED WX GRIDS TO REMOVE SHOWERS. WARM FRONT WILL HAVE CLEARED MUCH OF THE AREA MONDAY WITH A HOT AIR MASS MOVING INTO THE REGION. THE 00Z KBUF OBSERVED SOUNDING SHOWED +11C AT 700MB WHICH INDICATED A STRONG MID-LEVEL CAP. FEEL CONVECTIVE ACTIVITY MONDAY WILL BE CONFINED TO ALONG THE FRONT WHERE SOME LOW LEVEL CONVERGENCE COULD POP UP A SHOWER. MEMORIAL DAY TEMPERATURES WILL BE QUITE WARM WITH MOST HIGHS IN THE UPPER 80S TO LOWER 90S. SOME HEAT INDEX VALUES COULD POSSIBLY APPROACH 100F ESPECIALLY THOUGH SOME OF THE SOUTHERN TIER AND GENESEE RIVER VALLEYS. THERE WILL BE SOME RELIEF DUE TO THE SOUTHWEST GRADIENT THAT WILL DEVELOP BY AFTERNOON. RECORD HIGHS AT BUFFALO 86F/1987 AND ROCHESTER 93F/1911 WILL CERTAINLY BE CHALLENGED. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... A VERY WARM AND MUGGY AIRMASS WILL REMAIN ACROSS THE REGION MONDAY NIGHT WITH MANY AREAS NOT FALLING BELOW 70F. GIVEN THE WARMTH...INSTABILITY AND A 40 KNOT LOW LEVEL JET DURING THE OVERNIGHT...SHOWERS AND THUNDERSTORMS ARE POSSIBLE THROUGH THE OVERNIGHT HOURS. EXPECT ANOTHER WARM DAY ON TUESDAY WITH AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE DAY. ALTHOUGH DIFFICULT TO TIME...THE GFS IS DEPICTING A SERIES OF VORTICITY MAXIMA IN A SOUTHWESTERN UPPER FLOW AS THE UPPER RIDGE AXIS PASSES WELL EAST OF OUR AREA. WILL HAVE POPS IN THE LIKELY RANGE FOR MOST AREAS TUESDAY AFTERNOON AND EARLY EVENING. GFS AND ECMWF BOT SHOW THE BULK OF THE PRECIP TO BE AHEAD OF AN APPROACHING COLD FRONT...TO ARRIVE LATER ON TUESDAY NIGHT. TUESDAY NIGHT WILL BE A TIME OF GREATER CHANGES IN THE UPPER FLOW. A BROAD AND DEEP UPPER TROUGH ACROSS ONTARIO AND WESTERN QUEBEC PROVINCES TO THE GREAT LAKES WILL USHER IN A STRONG COLD FRONT WITH TEMPS FALLING BACK TO A MORE COMFORTABLE NIGHTTIME RANGE IN THE MID TO UPPER 50S. A SECONDARY FRONT AND UPPER VORTICITY MAX REMAIN JUST NORTH OF THE REGION ON WEDNESDAY WITH A WEAK NOSE OF HIGH PRESSURE EDGING INTO THE REGION FROM THE WEST. MOST MODEL GUIDANCE SHOWS ONLY SLIGHT CHANCE POPS. HIGH TEMPS ON WEDNESDAY TO BE IN THE UPPER TO LOWER 70S. EXPECT LOWS WEDNESDAY NIGHT IN THE UPPER 40S TO LOW 50S...SOME MID 40S ACROSS THE SOUTHERN TIER. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY AND FRIDAY WILL BE THE COOLEST DAYS OF THE WEEK WITH 850MB TEMPS RANGING FROM +3C TO +4C AND AFTERNOON HIGHS IN THE 60S FOLLOWED BY OVERNIGHT LOWS IN THE MID 40S TO LOW 50S. GFS AND ECMWF IN AGREEMENT WITH THE FORMATION OF A CUTOFF LOW ON FRIDAY AND HIGHER LIKELIHOOD OF RAIN ON FRIDAY AND FRIDAY NIGHT WITH TRAILING CHANCE POPS FOR SATURDAY. HIGH PRESSURE RIDGING NORTHWARD FROM THE SOUTHEASTERN STATES BRINGS A RETURN OF WARMER AIR ON SUNDAY WITH HIGHS BACK IN THE LOW TO MID 70S. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... MAINLY VFR CONDITIONS WITH MID LEVEL CIGS EXCEPT FOR KJHW WHICH RECENTLY IS REPORTING SOME MVFR FOG AS A RESULT OF SOME SHOWERS EARLIER TODAY. WINDS AT KBUF AND KIAG HAVE RECENTLY PICKED UP TO AROUND 12 KTS OUT OF THE SOUTH. THIS IS NOT THE WARM FRONT THOUGH...SEEMS TO BE A LOW LEVEL JET. KBUF VAD WINDS AND VELOCITY PRODUCT SHOWING AROUND 30KTS AT 1-2KFT WHICH IS MIXING DOWN. ALL OTHER SITES WILL REMAIN LIGHT AND VARIABLE. LATEST HRRR MODELS DOES NOT SHOW ANY NEW CONVECTION MOVING ACROSS THE AREA OVERNIGHT. WARM FRONT WILL LIFT ACROSS THE REGION BY MONDAY MORNING WITH A RIDGE OF WARM AIR ALOFT KEEPING CONVECTION CAPPED WITH VFR. OUTLOOK... TUESDAY...AREAS OF MVFR IN SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTH WINDS WINDS HAVE PICKED UP THIS EVENING AHEAD OF A WARM FRONT ALONG THE EASTERN END OF LAKE ERIE AND SOUTHWESTERN END OF LAKE ONTARIO. OTHERWISE PRETTY FAIR CONDITIONS ELSEWHERE. SOUTHWEST WINDS WILL INCREASE MONDAY...BUT DUE TO THE HOT AIR MASS ADVECTING INTO THE REGION THE OVER WATER STABILITY WILL LIMIT WIND SPEEDS AND PARTICULARLY WAVE HEIGHTS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH/TMA NEAR TERM...SMITH/TMA SHORT TERM...WCH LONG TERM...WCH AVIATION...SMITH MARINE...SMITH
AREA FORECAST DISCUSSION
NWS BUFFALO NY
753 PM EDT SUN MAY 27 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH ACROSS THE REGION TONIGHT SETTING THE STAGE FOR A HOT AND SULTRY MEMORIAL DAY. THE FRONT COULD ALSO HELP TO KICK OFF SOME BENEFICIAL SHOWERS AND THUNDERSTORMS. THE WARMTH WILL EASE ON TUESDAY AS A COLD FRONT WILL MOVE THROUGH THEN TEMPERATURES WILL ACTUALLY DROP TO BELOW NORMAL LEVELS FOR MUCH OF THE REST OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... UPDATED THE FORECAST FOR A CHANCE OF SHOWERS THIS EVENING ACROSS WESTERN NY. REGIONAL RADARS SHOWING AN AREA OF SHOWERS JUST TO THE WEST MOVING ACROSS SOUTHERN ONTARIO. IT HAS CONTINUED TO WEAKEN OVER THE LAST HOUR OR TWO AS IT MOVED ACROSS LAKE HURON. KEPT POPS LOW CHANCE SINCE IT MAY COMPLETELY FALL APART BY THE TIME IT REACHES WESTERN NEW YORK. LATER TONIGHT...A WARM FRONT LOCATED ACROSS SOUTHERN PENNSYLVANIA WILL SLOWLY LIFT NORTHWARD. 12Z MODELS SHOWED THE POTENTIAL FOR A WIDESPREAD COVERAGE OF NOCTURNAL CONVECTION TO DEVELOP ALONG THE NOSE OF DEEP MOISTURE TRANSPORT...WITHIN A HIGH MOISTURE RIBBON OF 850 MB THETA E NORTH OF THE FRONTAL ZONE. HOWEVER THE 21Z HRRR MODEL DOES NOT SHOW ANYTHING FORMING OVERNIGHT. IF THIS DOES INDEED HAPPEN...WIDESPREAD CONVECTION WILL LIKELY WORK ACROSS NORTHERN PORTIONS OF THE AREA. MODELS HAVE NOT HANDLED CONVECTIVE TRENDS VERY WELL OF LATE AND HAVE LOW CONFIDENCE THAT THIS WILL HAPPEN...THEREFORE HAVE ONLY SUGGESTED A LOW RISK FOR CONVECTION OVERNIGHT. WARM FRONT WILL HAVE CLEARED MUCH OF THE AREA MONDAY WITH A HOT AIR MASS MOVING INTO THE REGION. THE BEST CHANCES FOR CONVECTION WILL COME DURING THE AFTERNOON ALONG THE LAKE BREEZE BOUNDARY SOUTH AND EAST OF BUFFALO...POSSIBLY ALIGNED NORTH OF BUFFALO TO ROCHESTER IF A LAKE ONTARIO BOUNDARY CAN FORM. MEMORIAL DAY TEMPERATURES WILL BE QUITE WARM WITH MOST HIGHS IN THE UPPER 80S TO LOWER 90S...BASED ON CURRENT UPSTREAM READINGS. SOME APPARENT TEMPERATURES COULD POSSIBLY APPROACH 100F. THERE WILL BE SOME RELIEF DUE TO THE SOUTHWEST GRADIENT THAT WILL DEVELOP BY AFTERNOON. RECORD HIGHS AT BUFFALO 86F/1987 AND ROCHESTER 93F/1911 WILL CERTAINLY BE CHALLENGED. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... A VERY WARM AND MUGGY AIRMASS WILL REMAIN ACROSS THE REGION MONDAY NIGHT WITH MANY AREAS NOT FALLING BELOW 70F. GIVEN THE WARMTH...INSTABILITY AND A 40 KNOT LOW LEVEL JET DURING THE OVERNIGHT...SHOWERS AND THUNDERSTORMS ARE POSSIBLE THROUGH THE OVERNIGHT HOURS. EXPECT ANOTHER WARM DAY ON TUESDAY WITH AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH THE DAY. ALTHOUGH DIFFICULT TO TIME...THE GFS IS DEPICTING A SERIES OF VORTICITY MAXIMA IN A SOUTHWESTERN UPPER FLOW AS THE UPPER RIDGE AXIS PASSES WELL EAST OF OUR AREA. WILL HAVE POPS IN THE LIKELY RANGE FOR MOST AREAS TUESDAY AFTERNOON AND EARLY EVENING. GFS AND ECMWF BOT SHOW THE BULK OF THE PRECIP TO BE AHEAD OF AN APPROACHING COLD FRONT...TO ARRIVE LATER ON TUESDAY NIGHT. TUESDAY NIGHT WILL BE A TIME OF GREATER CHANGES IN THE UPPER FLOW. A BROAD AND DEEP UPPER TROUGH ACROSS ONTARIO AND WESTERN QUEBEC PROVINCES TO THE GREAT LAKES WILL USHER IN A STRONG COLD FRONT WITH TEMPS FALLING BACK TO A MORE COMFORTABLE NIGHTTIME RANGE IN THE MID TO UPPER 50S. A SECONDARY FRONT AND UPPER VORTICITY MAX REMAIN JUST NORTH OF THE REGION ON WEDNESDAY WITH A WEAK NOSE OF HIGH PRESSURE EDGING INTO THE REGION FROM THE WEST. MOST MODEL GUIDANCE SHOWS ONLY SLIGHT CHANCE POPS. HIGH TEMPS ON WEDNESDAY TO BE IN THE UPPER TO LOWER 70S. EXPECT LOWS WEDNESDAY NIGHT IN THE UPPER 40S TO LOW 50S...SOME MID 40S ACROSS THE SOUTHERN TIER. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY AND FRIDAY WILL BE THE COOLEST DAYS OF THE WEEK WITH 850MB TEMPS RANGING FROM +3C TO +4C AND AFTERNOON HIGHS IN THE 60S FOLLOWED BY OVERNIGHT LOWS IN THE MID 40S TO LOW 50S. GFS AND ECMWF IN AGREEMENT WITH THE FORMATION OF A CUTOFF LOW ON FRIDAY AND HIGHER LIKELIHOOD OF RAIN ON FRIDAY AND FRIDAY NIGHT WITH TRAILING CHANCE POPS FOR SATURDAY. HIGH PRESSURE RIDGING NORTHWARD FROM THE SOUTHEASTERN STATES BRINGS A RETURN OF WARMER AIR ON SUNDAY WITH HIGHS BACK IN THE LOW TO MID 70S. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... WEAKENING LINE OF SHOWERS MOVING ACROSS SOUTHERN ONTARIO THIS EVENING...HAVE INCLUDED VCSH IN WESTERN NY TAFS THROUGH 4-6Z OTHERWISE VFR CONDITIONS WITH MID LEVEL CIGS. WINDS WILL REMAIN LIGHT AND VARIABLE. LATEST HRRR MODELS DOES NOT SHOW ANY NEW CONVECTION MOVING ACROSS THE AREA OVERNIGHT. WARM FRONT WILL LIFT ACROSS THE REGION BY MONDAY MORNING WITH A RIDGE OF WARM AIR ALOFT KEEPING CONVECTION CAPPED WITH VFR. OUTLOOK... TUESDAY...AREAS OF MVFR IN SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... LIGHT WINDS AND FLAT CONDITIONS EXPECTED ON THE LAKES THROUGH TONIGHT...AS HIGH PRESSURE REMAINS ANCHORED ACROSS THE LOWER LAKES. A WARM FRONT WILL GRADUALLY LIFT NORTH ACROSS THE LOWER GREAT LAKES OVERNIGHT...BRINGING A CHANCE OF THUNDERSTORMS THROUGH SUNDAY EVENING WITH GUSTY WINDS AND HIGHER WAVES NEAR ANY THUNDERSTORMS. SOUTHWEST WINDS WILL INCREASE MONDAY...BUT DUE TO THE HOT AIR MASS ADVECTING INTO THE REGION THE OVER WATER STABILITY WILL LIMIT WIND SPEEDS AND PARTICULARLY WAVE HEIGHTS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH/TMA NEAR TERM...SMITH/TMA SHORT TERM...WCH LONG TERM...WCH AVIATION...SMITH MARINE...TMA
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1029 PM EDT SUN MAY 27 2012 .SYNOPSIS... TROPICAL STORM BERYL WILL MOVE ONSHORE NEAR JACKSONVILLE FLORIDA LATER TONIGHT. BERYL...OR THE REMNANTS OF BERYL...MAY BRING SUBSTANTIAL RAINFALL AND GUSTY WINDS TO THE AREA LATE TUESDAY INTO WEDNESDAY AS IT MOVES NORTHEAST OVER THE AREA. AN UNSEASONABLY STRONG UPPER TROUGH AND AN ASSOCIATED COLD FRONT MAY IMPACT THE EASTERN CAROLINAS LATE FRIDAY INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AS OF 1015 PM SUNDAY...ASIDE FROM SOME SHOWERS BETWEEN GEORGETOWN AND KINGSTREE RADAR SHOWS VERY LITTLE ACTIVITY ACROSS OUR FORECAST AREA CURRENTLY. 18Z SYNOPTIC MODELS PLUS THE LAST FEW HRRR RUNS SHOW SCATTERED SHOWERS DEVELOPING ACROSS THE SOUTH CAROLINA COASTAL WATERS IN THE NEXT FEW HOURS AND PUSHING ONSHORE FROM MYRTLE BEACH SOUTH THROUGH GEORGETOWN BY 2 AM. THIS SEEMS REASONABLE GIVEN THE MOIST UNSTABLE AIRMASS PRESENT COUPLED WITH INCREASING LOW-LEVEL CONVERGENCE IN THE NOCTURNAL ONSHORE FLOW. POPS IN THIS REGION ARE IN THE 30-40 PERCENT RANGE...WITH ONLY 20 PERCENT POPS OFF TO THE NORTH AND WEST. ACROSS INTERIOR SOUTHEASTERN NORTH CAROLINA A COOLER BOUNDARY LAYER SHOULD KEEP SHOWER CHANCES DOWN AROUND 10 PERCENT...TOO LOW FOR MENTION IN THE FORECAST OVERNIGHT. NO OTHER SIGNIFICANT CHANGES HAVE BEEN MADE AT THIS TIME. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... THE CENTER OF TROPICAL STORM BERYL HAS CROSSED THE GULF STREAM AND THE STORM WILL MAKE LANDFALL IN NORTHERN FLORIDA LATER TONIGHT. A TROPICAL AIRMASS CONTINUES TO STREAM ONSHORE IN THE MODERATE EASTERLY WINDS EXTENDING ACROSS ALL OF NORTH AND SOUTH CAROLINA. THIS SHOULD PROVIDE ANOTHER VERY MILD NIGHT WITH LOWS ONLY FALLING INTO THE UPPER 60S INLAND AND LOWER 70S NEAR THE COAST. (THIS IS 5-8 DEGREES ABOVE NORMAL) MODEL SOUNDINGS SHOW HIGH PRECIPITABLE WATER VALUES (1.60 TO 1.75 INCHES) AND NO CAPPING INVERSIONS ALOFT...SO THERE WILL CONTINUE TO BE A POTENTIAL OF ISOLATED SHOWERS MOVING ONSHORE THROUGH THE EVENING HOURS. SHOWER CHANCES SHOULD END INLAND LATER THIS EVENING...BUT CHANCES MAY ACTUALLY INCREASE ACROSS THE COASTAL WATERS AND ALONG THE SOUTH CAROLINA COAST AROUND MIDNIGHT AS LOW-LEVEL WIND CONVERGENCE INCREASES DUE TO DIURNAL COOLING OCCURRING INLAND BUT NOT OVER THE OCEAN. ALL IN ALL...CHANGES FROM THE PRIOR FORECAST ARE MINOR. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...TROPICAL STORM BERYL OR ITS REMNANTS WILL LIKELY BE W OF JACKSONVILLE FL AT THE START OF THE PERIOD. THE OFFICIAL FORECAST ISSUED BY THE NATIONAL HURRICANE CENTER WEAKENS BERYL TO A DEPRESSION BY MON NIGHT. A DEEPENING TROUGH...APPROACHING FROM THE W...IS EXPECTED TO PICK UP BERYL AND TURN IT NORTHWARD TUE AND THEN NE AS IT ACCELERATES UP THE SOUTHEAST COAST. STRONG SHEAR AND LAND INTERACTION WILL TAKE ITS TOLL ON BERYL AND IT IS NOT CLEAR WHAT SHAPE THE SYSTEM WILL BE IN WHEN IT BEGINS ITS ACCELERATION TO THE NE. THE OFFICIAL FORECAST REEMERGES A WEAK SYSTEM OFF THE SOUTH CAROLINA COAST TUE NIGHT AND THEN SHOWS SOME MODEST INTENSIFICATION WITH LOW PRESSURE PASSING WITHIN 40 MILES OF THE MOUTH OF THE CAPE CAPE FEAR RIVER WED MORNING. THE OFFICIAL FORECAST TRACK LIES ON THE EASTERN SIDE OF MODEL CONSENSUS. REGARDLESS OF THE EXACT TRACK AND STRENGTH...CONFIDENCE IS GROWING FOR A SIGNIFICANT RAIN EVENT AS DEEP TROPICAL MOISTURE GETS STEERED NORTHWARD. AT THIS TIME A GOOD 2 TO 3 INCH RAINFALL IS IN THE OFFING WITH A LIKELIHOOD THAT THE HEAVIEST RAIN WILL FALL ACROSS THE EASTERN TWO-THIRDS OF THE FORECAST AREA. CONVECTION ON MON WILL BE LARGELY DIURNALLY DRIVEN AND UNRELATED TO BERYL...WILL KEEP POPS IN SLIGHT CHANCE TO LOW CHANCE RANGE. TIMING IS NOT NAILED DOWN...BUT IN GENERAL...RAIN AND THUNDERSTORMS WILL BE SPREADING NORTHWARD ON TUE WITH THE HEAVIEST RAINFALL RATES EXPECTED LATE TUE INTO WED. THIS MAY POSE SOME HIGH WATER/PONDING ISSUES IN FLOOD PRONE AREAS. WINDS WILL BE ON THE INCREASE TUE NIGHT AND MAY GUST AS HIGH AS 30 TO 35 MPH NEAR/AT THE BEACHES. PREDICTED TIDES WILL NOT BE SIGNIFICANT GIVEN WE WILL BE JUST PAST THE FIRST QUARTER AND SO WE WOULD NEED +1.5 TO 2 FT DEPARTURES...BEFORE COASTAL FLOODING WOULD BE A CONCERN AND WE ARE NOT EXPECTING DEPARTURES OF THAT MAGNITUDE AT THIS TIME. THE HIGHEST OF THE TWO HIGH TIDES WILL OCCUR DURING THE EVENING. THE SURF WILL BE ROUGH AND THE RIP CURRENT RISK ELEVATED TO BE SURE. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 3 PM SUNDAY...BERYL WILL BE IMPACTING THE REGION AT THE START OF THE PERIOD...THOUGH TIMING STILL AN ISSUE. NHC SOLUTION IS BETWEEN THE FASTER ECMWF AND THE SLOWER GFS...THOUGH CLOSER TO THE ECMWF. TIMING WILL DEPEND ON HOW LONG THE SYSTEM STAYS OVER FL/GA. ANOTHER QUESTION IS WHAT SHAPE WILL THE STORM BE AS IT IS PICKED UP BY A BROAD MID LEVEL TROUGH AND LIFTED NORTHEAST. CURRENT FORECAST HAS THE STORM BECOMING A MARGINAL TROPICAL STORM AS IT PASSES THE AREA...BUT IT COULD JUST AS EASILY BE SUB TROPICAL OR EXTRA TROPICAL. HOWEVER THE DIFFERENCE AS FAR AS THE RESULT IS CONCERNED IS NEGLIGIBLE. 20 TO 30 MPH WINDS ALONG THE COAST...SLIGHTLY LESS INLAND...CAN BE EXPECTED...BUT THE BIGGER ISSUE WILL BE RAINFALL. HPC FORECAST IS 3 TO 6 INCHES BUT BASED ON LATEST TRACK MOST OF THIS WILL FALL BEFORE THE START OF THE PERIOD. PRECIP WILL LINGER INTO WED...ESPECIALLY ALONG THE COAST...SO HAVE BUMPED POP TO LIKELY AT THE COAST DECREASING TO CHANCE WELL INLAND. THU IS A TRANSITION DAY WITH FLAT UPPER PATTERN IN THE WAKE OF BERYL TRANSITIONING TO BROAD 5H TROUGHING OVER THE EASTERN US BY FRI MORNING. 5H TROUGH HELPS PUSH COLD FRONT...ASSOCIATED WITH A SYSTEM MOVING THROUGH THE OHIO VALLEY FRI...ACROSS THE AREA FRI NIGHT. DEEP SOUTHERLY FLOW AHEAD OF THE FRONT/TROUGH AND DIVERGENCE ALOFT ENHANCE PRECIP CHANCES FRI...THOUGH ONLY GOING CHANCE FOR NOW. BEST DYNAMICS AND DEEPEST MOISTURE REMAIN NORTHWEST OF AREA. COLD FRONT PUSHES OFF THE COAST LATE SAT MORNING WITH UPPER TROUGH AXIS FOLLOWING SAT NIGHT...DRYING THE AREA OUT FOR THE WEEKEND. CLOUDS AND RAIN WILL KEEP HIGHS A LITTLE BELOW CLIMO ON WED. TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE CLIMO INTO SAT MORNING. MOIST SOUTHERLY FLOW AHEAD OF THE COLD FRONT WILL KEEP LOWS WELL ABOVE CLIMO THU AND FRI NIGHT...NEAR 70 SLIGHTLY COOLER INLAND. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... AS OF 00Z...A VERY MOIST AIRMASS WILL CONTINUE ACROSS THE TERMINALS THIS TAF VALID PERIOD. SCATTERED TO BROKEN MVFR LEVEL CLOUDS THIS EVENING AT THE COASTAL TERMINALS WILL BECOME PRIMARILY BROKEN LATER THIS EVENING. IFR CEILINGS ARE POSSIBLE...BUT AS OCCURRED THE PREVIOUS COUPLE OF NIGHTS IN THIS SAME AIRMASS EXPECT ANY IFR TO BE SHORT LIVED AND WILL OMIT FROM TAFS ATTM. WITH DEEP SOUTHEAST MOIST FLOW ISOLATED SHOWERS ARE POSSIBLE AT ANY TIME...BUT EXPECT THE BEST POTENTIAL BY THE PRE-DAWN HOURS AT THE COASTAL TERMINALS AS SHOWERS INCREASE OFFSHORE AND MOVE TOWARDS SHORE. AT FLO/LBT VFR CONDITIONS THIS EVENING WILL GIVE WAY TO MVFR CEILINGS BY 08Z. AFTER SUNRISE PRIMARILY BROKEN MVFR CEILINGS CAN BE EXPECTED UNTIL AFTERNOON WHEN CEILINGS SHOULD BECOME MOSTLY VFR. SCATTERED SHOWERS EXPECTED TERMINAL-WIDE...WITH THE BEST CHANCE OF SHOWERS AT THE COASTAL TERMINALS DURING THE MORNING AND THE INLAND TERMINALS DURING THE AFTERNOON. SOUTHEASTERLY WINDS EXPECTED THROUGH THE TAF VALID PERIOD...STRONGEST AT THE COASTAL TERMINALS. EXTENDED OUTLOOK...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THROUGH THE EXTENDED PERIOD...WITH THE BEST CHANCE WEDNESDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SUNDAY...WIND AND WAVE OBSERVATIONS SUPPORT THE LATEST FORECAST. NO CHANGES ARE NEEDED WITH THIS LATE EVENING UPDATE. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... TROPICAL STORM BERYL IS APPROACHING A LANDFALL IN NORTHERN FLORIDA LATER TONIGHT. A BROAD ZONE OF EASTERLY WINDS NORTH OF THE STORM EXTENDS AS FAR NORTH AS THE OUTER BANKS. EAST WINDS WILL VEER SOUTHEASTERLY TONIGHT AS BERYL MOVES FARTHER WEST AND WE ENTER THE NORTHEASTERN PORTION OF THE CYCLONIC VORTEX SURROUNDING THE STORM. WIND SPEEDS NORTH OF CAPE FEAR WILL ONLY AVERAGE 10-15 KT...BUT WILL INCREASE MOVING SOUTH ALONG THE SOUTH CAROLINA COASTLINE...REACHING 20 KNOTS OR SO EAST OF WINYAH BAY AND THE SANTEE RIVER ENTRANCES. SMALL CRAFT ADVISORIES WILL REMAIN POSTED THROUGH THE NIGHT FOR 4-6 FT SEAS...HIGHEST EAST OF FRYING PAN SHOALS DUE TO SWELL IN DEEPER WATER...AND ALSO SOUTH OF MYRTLE BEACH DUE TO STRONGER WIND SPEEDS OCCURRING HERE. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...S WINDS THROUGH TUE WILL BACK TO THE SE OR ESE AND INCREASE FROM S TO N TUE NIGHT INTO WED. THE STRONGEST WINDS WILL OCCUR LATE TUE NIGHT INTO WED MORNING AS BERYL...OR ITS REMNANTS...APPROACH FROM THE SW AND THEN MOVE ACROSS OR IN CLOSE PROXIMITY TO THE COASTAL WATERS. THIS MAY BRING TROPICAL STORM FORCE WIND GUSTS TO THE AREA LATE TUE NIGHT AND EARLY ON WED. SEAS OF 4 TO 5 FT MON MORNING WILL SUBSIDE TO 3 TO 4 FT MON AFTERNOON AND MON NIGHT. SEAS WILL NOT BEGIN TO RAMP UP UNTIL TUE NIGHT...BUILDING TO 7 TO 10 FT LATE TUE NIGHT AND WED MORNING. MARINERS SHOULD CONTINUE TO CAREFULLY FOLLOW THE FORECAST THROUGH MID WEEK. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 3 PM SUNDAY...EXITING BERYL WILL KEEP STRONG WINDS AND INCREASED SEAS ACROSS THE WATERS WED. AT THIS POINT IT SEEMS HEADLINES WILL BE NEEDED...THOUGH NOT SURE IF THEY WILL BE TROPICAL STORM OR GALE...THOUGH THE END RESULT WILL BE THE SAME. STRONG BACKING WINDS THROUGH THE DAY WED AS BERYL LIFTS NORTHEAST...THOUGH EXACT TIMING STILL SOMEWHAT IN QUESTION. BRIEF PERIOD OF OFFSHORE FLOW IN THE WAKE OF BERYL WED NIGHT INTO THU BUT WINDS BACK TO SOUTH-SOUTHEAST DURING THU AS COLD FRONT APPROACHES FROM THE WEST. COLD FRONT DOES NOT CROSS THE WATERS UNTIL LATE FRI NIGHT OR SAT MORNING. AHEAD OF THE FRONT THE PINCHED GRADIENT WILL PRODUCE SOUTHWEST FLOW IN THE 15 TO 20 KT RANGE...WITH PROLONGED FETCH POTENTIALLY BUILDING SEAS HIGH ENOUGH TO WARRANT SCA LATE IN THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR SCZ054- 056. NC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ106- 108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR AMZ250-252-254- 256. && $$ NEAR TERM...TRA SHORT TERM...RJD LONG TERM...III AVIATION...MRR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
941 PM CDT SUN MAY 27 2012 .SHORT TERM... ADJUSTED POPS AND THUNDER CHANCES TO RADAR AND HRRR MODEL FORECAST. WITH INCREASED POPS SOUTH CENTRAL AND SOME DECREASED POPS WEST CENTRAL. TRENDS TWEAKED TO CURRENT OBSERVATIONS. .AVIATION...ALL AERODROMES HAVE TRENDED TO VFR CONDITIONS AND THIS WILL CONTINUE OVERNIGHT. TOMORROW MVFR CEILINGS WILL DEVELOP AS MID LEVEL LOW MOVES NORTH OF THE REGION AND COLD AIR ALOFT MOVES INTO WESTERN AND CENTRAL NORTH DAKOTA. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HW AVIATION...HW
AREA FORECAST DISCUSSION
NWS BISMARCK ND
658 PM CDT SUN MAY 27 2012 .SHORT TERM...INCREASED POPS TO SLIGHT CHANCE OVER MOST OF WESTERN AND CENTRAL COUNTIES WITH CONVECTION APPROACHING SOUTHERN BORDER FROM BOWMAN TO FT YATES. HRRR SHOWS THIS DECREASING SOME AND MOVING MORE TOWARD THE EAST LATER SO DID NOT GO ABOVE SLIGHT CHANCE. OTHERWISE ADJUSTED DIURNAL TRENDS. .AVIATION... LIFR CEILINGS CONTINUED NORTH OF SURFACE LOW IN NORTH CENTRAL AREAS...WITH A CHANCE OF MVFR SHOWERS AND ISOLATED THUNDERSTORMS IN THE SOUTHWEST AND SOUTHCENTRAL AS DEVELOPING CONVECTION APPROACHES THE SOUTHERN BORDER. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...HW AVIATION...HW
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1055 PM CDT SUN MAY 27 2012 .DISCUSSION... SURFACE FRONT HAS BECOME MORE DIFFUSE ACROSS THE AREA WITH WINDS MIXING OUT TO A SOUTHWESTERLY DIRECTION ALOFT. SATELLITE INDICATES CUMULUS FIELD ALONG AND EAST FROM MARSHALL MN DOWN INTO CENTRAL NEBRASKA. CUMULUS FIELD ALONG AND NORTH OF I-90 IS FAIRLY FLAT AT THIS POINT...HOWEVER...FURTHER TO THE SOUTH ACROSS EASTERN NEBRASKA CLOUDS ARE A BIT MORE VIGOROUS WITH LIGHT ECHOS ON RADAR. AS UPPER LEVEL WAVE OVER NORTHERN ROCKIES PINWHEELS NORTHEAST INTO THE NORTHERN PLAINS AND UPPER LEVEL JET STREAK NOSES INTO THE AREA EXPECT WEAK CAPPING INVERSION ACROSS THE AREA TO BE OVERCOME WITH THUNDERSTORM DEVELOPMENT AROUND 22Z. HRRR HAS BEEN FAIRLY CONSISTENT WITH DEVELOPMENT DURING THIS TIME FRAME. WITH INITIAL UPDRAFT DEVELOPMENT EXPECT STORMS TO CARRY A HAIL THREAT...WITH HAIL UP TO AROUND 2 INCHES IN DIAMETER. CAPE PROFILES ARE FAIRLY THIN...WITH A NORMALIZED CAPE VALUE AROUND 0.15. AS COLDER AIR MOVES IN ALOFT...WET BULB ZERO HEIGHT DROPS FROM AROUND 11K FEET TO 7K OR SO...BUT EXPECT STORMS TO BE FAIRLY LINEAR BY THIS POINT. STORMS SHOULD BECOME LINEAR FAIRLY QUICKLY...AND ONCE THEY DO SO TAKE ON A STRONG WIND POTENTIAL. MODEL SOUNDINGS INDICATE AIR ABOVE 600 MB IS RELATIVELY DRY...ENHANCING DOWNDRAFT POTENTIAL. IN ADDITION...WINDS ARE FAIRLY STRONG ALOFT WITH 40-60 KTS ABOVE 700 MB. WITH UNIDIRECTIONAL WINDS FROM THE SURFACE TO THE TOP OF THE TROPOSPHERE...IT SHOULD BE EASY TO BRING WINDS DOWN TO THE SURFACE...AND THINK LARGE SECTION OF THE EASTERN HALF OF THE FORECAST AREA FACES A FAIRLY HIGH WIND THREAT WITH STRAIGHT LINE WINDS IN EXCESS OF 70 MPH...WITH THE POTENTIAL FOR STRONGEST STORMS TO EXCEED 80 MPH. AS STORMS EVOLVE INTO A LINE...EXPECT HAIL THREAT TO DIMINISH...WITH POTENTIAL OF HALF DOLLAR SIZED HAIL. SEVERE THREAT SHOULD ABATE FROM WEST TO EAST MAINLY WORKING EAST FORECAST AREA AFTER 05Z. MODELS INDICATE POTENTIAL OF SOME LOW LYING STRATUS DEVELOPING LATE TONIGHT ALONG AND EAST OF HIGHWAY 60...BUT CONFIDENCE IS LOW AT THIS POINT. /BT MONDAY AND TUESDAY WILL BOTH PROVE TO BE BREEZY AND COOLER AS THE UPPER LEVEL LOW WRAPS UP OVER NORTH DAKOTA ON MONDAY AND MOVES INTO THE GREAT LAKES REGION ON TUESDAY. THE AIR MASS WILL BE MILDER ON MONDAY WITH GOOD MIXING SO WENT JUST A BIT ABOVE GUIDANCE BECAUSE OF THE MIXY ENVIRONMENT. RELATIVELY COOL ON MONDAY NIGHT BUT WITH COLD AIR ADVECTION EXPECTED WINDS SHOULD NOT DROP OFF TOO MUCH SO STICKING WITH MID TO UPPER 40S SEEMS REASONABLE. WITH COLDER AIR IN PLACE ON TUESDAY HIGHS WILL BE ABOUT 5 TO 10 DEGREES COOLER AND IT WILL STILL BE BREEZY. WITH HIGHS ONLY IN THE LOWER TO MID 60S AND A NORTHWEST WINDS AT 15 TO 25 MPH WILL FEEL FAIRLY COOL. HIGH PRESSURE WILL BUILD SOUTH ON TUESDAY NIGHT AND REMAIN IN PLACE ON WEDNESDAY BRINGING ANOTHER VERY COOL DAY...ALBEIT WITH MUCH LESS WIND. REGARDLESS LOWS IN THE UPPER 30S TO LOWER 40S AND HIGHS IN THE LOWER TO MID 60S WILL STILL FEEL PRETTY COOL. UPPER LEVEL SUPPORT AND PLENTY OF MID LEVEL MOISTURE WILL BRING A THREAT FOR RAINFALL LATE TUESDAY NIGHT THROUGH EARLY THURSDAY MORNING...WITH THE BETTER CHANCES SOUTH OF INTERSTATE 90. IF THIS SYSTEM IS 3 TO 6 HOURS FASTER THAN EXPECTED HIGHS COULD EASILY GET STUCK IN THE 50S OVER MUCH OF THE AREA. WHILE RAINFALL AMOUNTS WILL LIKELY TO EXCEED A QUARTER OF AN INCH MOST LOCATIONS WILL LIKELY SEE A TENTH OF AN INCH OR SO. INSTABILITY PRETTY MARGINAL SO ONLY HAVE A SLIGHT CHANCE FOR THUNDERSTORMS AROUND THE MISSOURI RIVER AREA. IN THE LATTER PERIODS(THU/SUN)...STILL LOOKS COOL EARLY IN THE PERIOD WITH GRADUAL WARMING THROUGH THE WEEKEND. A LITTLE DISAGREEMENT ON SUNDAY WITH JUST HOW WARM TO GO BUT OVERALL DECENT AGREEMENT ON BROAD SCALE PATTERN. LOOKING PRETTY MUCH DRY THROUGH THE PERIOD WITH A TAIL END THREAT ON THURSDAY AS WAVE EXITS THE AREA THEN SOME POTENTIAL FOR THUNDERSTORMS SATURDAY NIGHT AS WARMER AIR RETURNS. HIGHS THURSDAY IN THE 60S WILL WARM INTO THE 70S FRIDAY THEN INTO THE 80S BY SUNDAY. /08 && .AVIATION.../FOR THE 06Z TAF ISSUANCE/ SHOWERS AND THUNDERSTORMS WILL CONTINUE TO TRACK NORTH NORTHEASTWARD ACROSS NORTHWEST IOWA...SOUTHWEST MINNESOTA AND EXTREME SOUTHEAST SOUTH DAKOTA. THE SEVERE WEATHER THREAT HAS DIMINISHED...BUT GUSTY WINDS AND LOCALLY MVFR VISIBILITIES ARE POSSIBLE WITH THE REMAINING STORMS. SHOWERS AND THUNDERSTORMS WILL END FROM WEST TO EAST BY AROUND 09Z. VFR CONDITIONS WILL RULE LATE TONIGHT THROUGH 06/TUE. WINDS WILL BECOME BREEZY FROM THE WEST NORTHWEST AFTER 14Z. && .FSD WATCHES/WARNINGS/ADVISORIES... IA...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH MONDAY MORNING FOR IAZ001>003-012>014-020>022-031-032. MN...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH MONDAY MORNING FOR MNZ072-080-081-089-090-097-098. NE...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH MONDAY MORNING FOR NEZ014. SD...FLASH FLOOD WATCH FROM THIS AFTERNOON THROUGH MONDAY MORNING FOR SDZ071. && $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
345 PM CDT SAT MAY 26 2012 .DISCUSSION.../ISSUED AT 258 PM CDT/ STILL A TOUGH CALL ON TONIGHT WITH EXTREME INSTABILITY ALOFT. STILL A FAIRLY STOUT CAP NEAR 800 MB. RAP SOUNDINGS WEAKEN THE CAP BETWEEN 4-6 PM...BUT THINK THIS IS OVERDONE. CERTAINLY SOME MASS CONVERGENCE ACROSS NORTHEAST NEBRASKA AS THE SURFACE WARMFRONT CONTINUES TO LIFT TO THE NORTH...BUT EVEN SATELLITE SHOWS MOSTLY CLEAR SKIES ACROSS THE AREA...ANOTHER INDICATION OF THE STRONG CAP. HRRR HAS BEEN CONSISTENTLY DEVELOPING CONVECTION THE PAST FEW RUNS NEAR THE JAMES RIVER VALLEY...BUT FEEL THIS IS OVERDONE AS ITS INITIALIZATION ON SURFACE TEMPERATURES ARE TOO WARM IN THE MODEL BY 5-10 DEGREES. INCREASING JET ACROSS NEBRASKA WILL AID IN ASSENT SLIGHTLY...BUT STILL THINK IT WILL BE TOUGH TO GET AROUND THE CAP. GREATEST POTENTIAL FOR THUNDERSTORM DEVELOPMENT APPEARS TO BE ACROSS NORTHERN NEBRASKA...THEN LIFTING NORTHEAST INTO OUR CWA. IT IS CERTAINLY UNSTABLE ALOFT WITH 3500-4000 J/KG OF CAPE. IF STORMS CAN DEVELOP DOWN SOUTH...AND THAT IS A BIG IF...POTENTIAL EXISTS FOR LARGE HAIL AND DAMAGING WINDS. IF STORMS ARE ABLE TO DEVELOP...EXPECT THEM TO FOLLOW THE 925 MB FRONT AS IT LIFTS NORTH THROUGH THE CWA. LOW TEMPERATURES WILL BE QUITE MILD TONIGHT WITH STRONG SOUTHERLY WIND AND LOW LEVEL JET...GENERALLY WARMER THAN IT HAS BEEN MUCH OF THE DAY. /BT SUNDAY SHOULD PROVE TO BE A VERY WARM AND SOMEWHAT BREEZY DAY WITHOUT MUCH THREAT FOR PRECIPITATION UNTIL AFTER ABOUT 300 PM CDT. BETTER FORCING WILL BE WELL NORTH OF THE AREA AND THE BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS WILL COME WITH THE APPROACH OF A FAIRLY POTENT MID AND UPPER LEVEL WAVE. THE MAIN AFFECTS OF THIS WAVE WILL BE FELT FROM ABOUT 21Z THROUGH 9Z AND WILL HIT THE POPS THE HARDEST DURING THIS TIME. WITH A WEAK WIND SHIFT/DRY LINE MOVING INTO THE WESTERN CWA...THE CHANCES FOR CONVECTION WEST OF THE JAMES RIVER VALLEY WILL BE MINIMAL WITH THE BEST CHANCE FROM AROUND A BROOKINGS TO YANKTON LINE EAST. WILL NOT ISSUE A FLASH FLOOD WATCH AT THIS TIME BUT SOME FAIRLY HEAVY RAIN OVERNIGHT IN PARTS OF PIPESTONE AND MOODY COUNTIES AS WELL AS EASTERN WOODBURY...CHEROKEE...CLAY IOWA AND DICKINSON COUNTIES. BELIEVE THAT THE MAIN THREAT WILL BE FOR A FEW LOCATIONS IN MAINLY NORTHWEST IOWA AND SOUTHWEST MINNESOTA TO GET AN INCH OR TWO OF RAINFALL WHICH COULD SET A FEW CREEKS/STREAMS AND RIVERS OUT OF THEIR BANKS IF IT FALLS IN THE RIGHT SPOT. THE OTHER ASPECT OF THIS SYSTEM WILL BE THE SEVERE WEATHER THREAT. WITH HE COLD FRONT ALOFT MOVING IN THROUGH THE DAY THE CAP WILL WEAKEN QUITE A BIT AND FROM ABOUT 22Z ON WILL BE DIFFICULT NOT TO SEE THUNDERSTORM ACTIVITY. AS STORMS DEVELOP THE ENVIRONMENT WILL BE SUPPORTIVE OF SEVERE THUNDERSTORMS WITH 1500 TO 2000 J/KG SFC BASED CAPE AND MODERATE 40 KNOT OR SO BULK SHEAR IN THE 0 TO 3KM AND 0 TO 6KM LAYERS. WHILE THE 0 TO 1KM BULK SHEAR IS TO POSSIBLY BE UP AROUND 20 KNOTS THE DIRECTIONAL ASPECT IS SEVERELY LACKING WITH FAIRLY UNIDIRECTIONAL SHEAR THROUGH THE ATMOSPHERE AHEAD OF THE BOUNDARY. SO LIKELY LOOKING AT THE THREAT FOR HALF DOLLAR TO GOLF BALL SIZE HAIL AND WIND GUSTS TO 70 MPH. BY SUNDAY NIGHT THIS ACTIVITY WILL SWEEP EASTWARD AND BY ABOUT 9Z OR 10Z LIKELY BE EAST OF THE CWA. COOLER AND MUCH LESS HUMID AIR WILL ADVECT IN SUNDAY EVENING LEADING TO LOWS MAINLY IN THE 50S. MONDAY AND MONDAY NIGHT LOOK COOL AND BREEZY AS WEST TO NORTHWEST FLOW KEEPS DRY AND MIXY CONDITIONS IN PLACE. HIGHS WILL MAINLY BE IN THE UPPER 60S TO MID 70S WITH LOWS ON MONDAY NIGHT FROM THE MID 40S TO NEAR 50. TUESDAY WILL CONTINUE COOL DRY WEST TO NORTHWEST FLOW WITH HIGHS IN THE 60S AND LOWS IN THE 40S. IN THE LATTER PERIODS(WED/SAT)...TROUGHING IN THE CENTRAL UNITED STATES AND RIDGING IN THE WEST WILL LIKELY LEAD TO A CONTINUED THREAT FOR BELOW NORMAL TEMPERATURES THROUGH THE PERIOD...ALTHOUGH GRADUAL WARMING IS EXPECTED. WHILE THERE IS STILL A THREAT FOR RAINFALL AND ISOLATED THUNDERSTORMS ON WEDNESDAY THE MODELS DO NOT AGREE MUCH ON PLACEMENT AND STRENGTH OF JET MAX...SO WILL LEAVE MID RANGE POPS IN PLACE. OTHERWISE LOOKING DRY THROUGH THE PERIOD. BASICALLY PLANNING ON 60S WEDNESDAY AND THURSDAY AND 70 FRIDAY AND SATURDAY. AT THIS TIME IT DOES APPEAR THAT THE RIDGE WILL SPREAD ACROSS THE PLAINS BY THE WEEKEND. /08 && .AVIATION.../FOR THE 18Z TAF ISSUANCE/ STRATUS WILL HANG TOUGH ALONG AND NORTH OF I-90...WHILE KSUX SHOULD REMAIN VFR THROUGH THE AFTERNOON HOURS. STORMS MAY TRY TO DEVELOP AFTER 22Z...AND IF THEY DEVELOP...THEY SHOULD PRODUCE VERY LARGE HAIL AND DAMAGING WINDS...BUT THE CHANCE OF ANY DEVELOPMENT IS LOW. SURFACE WARM FRONT IS EXPECTED TO LIFT NORTH ACROSS THE AREA...AND AS IT DOES SO LOW LYING STRATUS AND MVFR CONDITIONS SHOULD GIVE WAY TO VFR. SOUTHERLY WINDS ARE EXPECTED THROUGH MUCH OF THE DAY ON SUNDAY AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA ON SUNDAY NIGHT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. $$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1130 AM CDT SAT MAY 26 2012 .DISCUSSION... COMPLICATED SET UP TODAY WITH LARGE AMOUNT OF STRATUS ACROSS MUCH OF THE AREA. CLEARING STARTING TO DEVELOP ACROSS FAR SOUTHEASTERN SOUTH DAKOTA INTO PORTIONS OF NORTHWEST IOWA...BUT STILL A FAIR AMOUNT OF CONVECTIVE DEBRIS ACROSS THE AREA. 12Z SOUNDINGS AT KOMA AND KLBF SHOW VERY STOUT CAP LIFT NORTH...WHICH BRING CONVECTIVE CHANCES INTO QUESTION. CERTAINLY VERY STEEP LAPSE RATES ALOFT ESPECIALLY IN THE 700-500 MB LAYER...LEADING TO CAPE VALUES OF 4-5K. IF STORMS ARE ABLE TO GET AROUND THE CAP...EXPLOSIVE CONVECTION WOULD LEAD TO EXTREMELY LARGE HAIL...DAMAGING WINDS AND MAYBE AN ISOLATED TORNADO OR TWO. HRRR HAS SUGGESTED STORMS MAY TRY TO DEVELOP SOUTH OF CLEARING AFTER 22Z...BUT FORECAST SOUNDINGS SHOW COOLING IN THE MID AFTERNOON HOURS THAT MAY NOT BE REAL. AS SUCH...HAVE TRIMMED BACK STORM POTENTIAL...ESPECIALLY NORTH OF 90. IF STORMS GO...THINK IT WOULD BE CLOSER TO 00Z...BUT THAT IS STILL A BIG IF. HAVE SLOWED WARMING COMPARED TO FORECAST AND MODELS WITH STRATUS ACROSS THE AREA...AND HAVE ALSO LOWERED HIGHS SOME. && .AVIATION.../FOR THE 18Z TAF ISSUANCE/ STRATUS WILL HANG TOUGH ALONG AND NORTH OF I-90...WHILE KSUX SHOULD REMAIN VFR THROUGH THE AFTERNOON HOURS. STORMS MAY TRY TO DEVELOP AFTER 22Z...AND IF THEY DEVELOP...THEY SHOULD PRODUCE VERY LARGE HAIL AND DAMAGING WINDS...BUT THE CHANCE OF ANY DEVELOPMENT IS LOW. SURFACE WARM FRONT IS EXPECTED TO LIFT NORTH ACROSS THE AREA...AND AS IT DOES SO LOW LYING STRATUS AND MVFR CONDITIONS SHOULD GIVE WAY TO VFR. SOUTHERLY WINDS ARE EXPECTED THROUGH MUCH OF THE DAY ON SUNDAY AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA ON SUNDAY NIGHT. && .PREV DISCUSSION.../ISSUED AT 406 AM CDT/ WILL GIVE A FAIRLY BRIEF DISCUSSION WITH THE ONGOING CONVECTION CONCERNS...WITH MOST OF THE WEATHER CHALLENGES CONFINED TO THIS WEEKEND ANYWAY. CURRENTLY...VERY STRONG WARM FRONT ALOFT WITH ASSOCIATED STRONG THETA E ADVECTION CONTINUES TO LIFT NORTHWARD SPARKING SCATTERED THUNDERSTORMS. AS THE STORMS MOVE NORTHWARD... THERE ARE STILL INDICATIONS THAT THE ACTIVITY WILL COALESCE AND FILL IN PRIMARILY NORTH OF I 90 WHERE THE STRONG INTERACTION WITH THE 850MB FRONT IS. THEREFORE EARLY THIS MORNING...CONTINUED THE TREND OF GOING HIGH POPS FOR AREAS NORTH OF I 90...BUT ONLY TIME WILL TELL HOW MUCH THE CONVECTION FILLS IN ACROSS SW MINNESOTA. WITH VERY HIGH ELEVATED CAMPS AND STRONG WIND SHEAR...AN ISOLATED SEVERE STORM IS POSSIBLE EARLY TODAY. THEN DURING THE MIDDAY HOURS IS WHEN WE MAY FIND A BREAK IN THE ACTION. BUT LATE THIS AFTERNOON AND EARLY EVENING IS CONCERNING. MASSIVE ML CAPE VALUES EXCEEDING 2000 J/KG ARE EVIDENT ON MULTIPLE MODELS LATE TODAY. IN ADDITION...THE NEXT STRONG ROUND OF 700MB THETA E ADVECTION MOVES NORTHWARD AND WITH THE AMOUNT OF SURFACE HEATING EXPECTED SOUTH OF THE 850MB FRONT...THE CAP COULD VERY WELL BREAK. BOTH THE NAM...ECMWF AND THE GEM REGIONAL HINT AT THE STRONGEST CONVECTION BEING IN A BAND FROM YANKTON TO SIOUX CITY... NORTHEASTWARD THROUGH THE SIOUX FALLS AREA AND INTO SW MINNESOTA. TIMING WISE IS FOR THE VERY LATE AFTERNOON AND EVENING HOURS. THIS IS A SUPERCELL TYPE SITUATION WITH LARGE HAIL AND DAMAGING WINDS...DEEP LAYER VEERING WIND SHEAR AND 0-3KM BULK SHEAR VECTORS A STRONG 45 TO 50 KNOTS THROUGH THIS AREA. BUT THE ACTIVITY WILL LIKELY BE OF A SCATTERED NATURE. CONCERNING TEMPERATURES...WITH THE WARM FRONT LIFTING A BIT FURTHER NORTHWARD THAN PREVIOUSLY THOUGHT...WARMED UP SOME MAX TEMPERATURES FOR TODAY ALONG THE I 90 CORRIDOR AND THROUGH OUR NORTHERN ZONES. LATE SUNDAY AND SUNDAY EVENING IS WHEN THE NEXT MAJOR ACTION WILL TAKE PLACE...WITH OUR WELL ADVERTISED VERY STRONG MID LEVEL IMPULSE RIDING NORTHEASTWARD JUST AHEAD OF A SURFACE COLD FRONT. ALL MODELS CONTINUE TO INITIATE CONVECTION AS THEY HAVE BEEN FOR SEVERAL DAYS NOW...PRIMARILY ALONG AND EAST OF A TYNDALL SD TO BROOKINGS SD LINE. MENTIONED A CHANCE FOR SEVERE WEATHER IN THE VERY LATE AFTERNOON AND EVENING. DIRECTIONAL SHEAR IS NOT AS IMPRESSIVE ON SUNDAY AS IT IS TODAY...BUT THE SPEED SHEAR REMAINS VERY STRONG WITH 60 TO 65 KNOTS WIDESPREAD AT 6KM. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. $$
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1229 AM CDT SAT MAY 26 2012 .UPDATE... SEE UPDATED AVIATION DISCUSSION BELOW. LATEST NAM12 SHOWS THAT LOLVL MOISTURE WILL TAKE A BIT LONGER TO PUSH NORTHWARD...ALONG WITH ASSOCIATED WAA -SHRA/TSRA. HRRR MODEL WHICH HAS BEEN DOING FAIRLY WELL WITH FCSTD REFLECTIVITIES ALSO SHOWS THIS SLOWER DEVELOPING TREND. HAVE TWEAKED WX/POP GRIDS TO REFLECT THIS THINKING. WDLY SCT -SHRA/TSRA DO PERSIST ACROSS THE NERN PART OF THE CWA...BUT WITH DWPTS STILL IN THE 40S NEAR THE ND BORDER...FEEL THAT VAST MAJORITY OF ECHOS REPRESENT VIRGA. BY 12Z SHOULD STILL SEE A GOOD PART OF CWA UNDER PCPN SHIELD...SO KEPT HIGHER POPS IN PLACE AFT 09Z. && .PREVIOUS DISCUSSION... .SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT FORECAST CHALLENGES SURROUND INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS BY LATE TONIGHT/EARLY SATURDAY MORNING...WHICH THEN PERSIST THROUGH LATE SATURDAY NIGHT ACROSS THE CWA. PRECIPITATION CHANCES ALSO LINGER INTO SUNDAY AFTERNOON/EVENING ACROSS THE FAR EASTERN FORECAST AREA. THERE APPEAR TO BE A COUPLE OF FORECAST PERIODS WHERE STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. CURRENTLY...A BAND OF LIGHT TO MODERATE /DEFORMATION ZONE-FORCED/ RAIN IS LIFTING UP ACROSS PORTIONS OF WESTERN INTO CENTRAL SOUTH DAKOTA...WHILE ANOTHER AREA OF SCATTERED /700HPA WAA AND MOISTURE-ADVECTION SUPPORTED/ RAIN SHOWERS IS DEVELOPING ACROSS SOUTHEAST SOUTH DAKOTA MOVING NORTHEAST TOWARD MINNESOTA. SKIES ARE PARTLY TO MOSTLY CLOUDY AND TEMPERATURES ARE SLOWLY WARMING INTO THE UPPER 50S TO MID 60S ACROSS THE CWA ON RATHER LIGHT AND VARIABLE WINDS. TONIGHT...THE DEFORMATION RAIN OUT WEST WILL CONTINUE TO SLOWLY LIFT UP INTO EASTERN MONTANA AND WESTERN NORTH DAKOTA...WHILE THE RAIN SHOWERS CURRENTLY OVER SERN SODAK CONTINUE TO CHUG OFF INTO SOUTHERN MINNESOTA. A FEW SHOWERS MAY WANDER INTO THE FAR SOUTHEASTERN FORECAST AREA THIS EVENING. THE BETTER CHANCE FOR SCATTERED TO NUMEROUS /ELEVATED/ SHOWERS AND THUNDERSTORMS LOOKS TO REALLY GET GOING LATE TONIGHT...MAINLY AT OR AFTER 09Z...ACROSS THE SOUTHERN HALF OF THE CWA WHEN A GOOD SURGE OF LOW LEVEL WAA AND MOISTURE ADVECTION WILL COINCIDE WITH A WEAK TO MODERATE LOW LEVEL JET PROGGED TO SET UP ACROSS THE CWA. EFFECTIVE SHEAR IN THE ATMOSPHERE LATE TONIGHT WILL SUPPORT THE DEVELOPMENT OF A FEW STRONG THUNDERSTORMS...PERHAPS CAPABLE OF PRODUCING LARGE HAIL. THAT GOOD ZONE FOR ASCENT ALOFT POTENTIALLY STICKS AROUND INTO SATURDAY AFTERNOON ACROSS THE EASTERN THIRD OF THE CWA...MAINLY OVER AND EAST OF THE PRAIRIE COTEAU. THIS IS STILL OUT AHEAD OF AN APPROACHING SURFACE WARM FRONT...SO CONVECTIVE POTENTIAL DURING THE DAY SATURDAY WILL STILL BE ELEVATED...IF ANY CAN DEVELOP. AND AGAIN...WITH THE COMBINED ELEVATED INSTABILITY AND SHEAR IN PLACE...A FEW STORMS COULD GROW TO BECOME STRONG TO SEVERE. IT IS SATURDAY EVENING/NIGHT THAT THE CONCERN OVER WARM FRONT PLACEMENT CONTINUES. IF THE GFS /WHICH HAS BEEN TO THIS POINT VERY CONSISTENT FROM RUN-TO-RUN/ PANS OUT...WILL HAVE TO MONITOR THINGS CLOSELY FOR SATURDAY EVENING MAINLY ALONG AND SOUTH OF INTERSTATE 90...FOR POTENTIALLY SUPER-CELLULAR CONVECTION CAPABLE OF PRODUCING LARGE HAIL...DAMAGING WINDS AND EVEN A TORNADO. MEANWHILE...NAM- BASED SOLUTIONS ALL CONTINUE TO SUGGEST THE THREAT FOR SEVERE WEATHER WILL EXIST FURTHER EAST ACROSS EXTREME EASTERN SOUTH DAKOTA INTO MINNESOTA. THE MODELS CONTINUE TO SHOWCASE VERY WARM MID-LEVELS IN THE ATMOSPHERE ON SATURDAY WHICH IS EXPECTED TO HOLD ANY SURFACE-BASED CONVECTION AT BAY OR KEEP THINGS CAPPED. IF A STORM SHOULD BEGIN TO DEVELOP...THOUGH...IT WOULD BE CAPABLE OF BECOMING SEVERE RATHER QUICKLY. THE SURFACE WARM FRONT IS EXPECTED TO PUSH UP INTO NORTH DAKOTA LATE SATURDAY NIGHT...EFFECTIVELY SHUTTING OFF PRECIPITATION POTENTIAL UNTIL LATER IN THE DAY ON SUNDAY WHEN A COLD FRONT SWEEPING THROUGH THE CWA COULD INITIATE CONVECTION ACROSS FAR EASTERN SOUTH DAKOTA INTO WEST CENTRAL MINNESOTA. SUNDAY NIGHT SHOULD BE DRY AND COOL AND BREEZY WITH LOW LEVEL CAA AND SUBSIDENCE HELPING TO KEEP THE BOUNDARY LAYER SOMEWHAT MIXED AND KEEP BREEZY TO WINDY NORTHWEST WINDS GOING MOST OF THE NIGHT. TEMPERATURES FOR MOST OF THE PERIOD ARE EXPECTED TO HOLD GENERALLY AT OR BELOW NORMAL WITH THE EXCEPTION OF SUNDAY. WIDESPREAD LOW STRATUS CLOUDS ARE EXPECTED TO DEVELOP BY LATE TONIGHT AND PERSIST FOR MOST OF SATURDAY ON EASTERLY PBL WINDS...KEEPING TEMPS DOWN. THE NORTHWARD SURGING WARM FRONT COULD ACTUALLY END UP KEEPING TEMPERATURES STEADY OR PERHAPS WARMING THEM OVERNIGHT SATURDAY NIGHT. INITIALLY IN WARMER AIR ON SUNDAY...A COLD FRONT WILL BLAST THROUGH THE CWA...WITH CAA WORKING INTO THE AREA ON ITS HEELS. BETTER MIXING WINDS ON SUNDAY...THOUGH...SO TEMPERATURES SHOULD WARM INTO THE 70S AND 80S...BEFORE THINGS COOL BACK DOWN TO NORMAL FOR LOW TEMPS SUNDAY NIGHT. .LONG TERM...MONDAY THROUGH FRIDAY THE PERIOD BEGINS WITH AN AREA OF LOW PRESSURE OVER NORTHERN ND. MARGINAL MID LEVEL TEMPERATURE LAPSE RATES ALONG WITH LIMITED LLM MAY RESULT IN AFTERNOON CU/SCT SPRINKLES FOR THE EASTERN CWA. MONDAY NIGHT AND MOST OF TUESDAY NIGHT APPEARS TO BE DRY AS AN AREA OF HIGH PRESSURE SETTLES OVER THE REGION. THE NEXT CHANCE FOR PCPN WILL LATE TUESDAY NIGHT THROUGH WEDNESDAY. AN AREA OF LOW PRESSURE MOVING ACROSS KANSAS...ALONG WITH A MID LEVEL SHORT WAVE DIVING SOUTHEASTWARD FROM THE NORTHERN HIGH PLAINS WILL COMBINE TO PRODUCE A DECENT CHANCE FOR SHOWERS...MAINLY FOR WESTERN AND SOUTHERN SOUTH DAKOTA. LITTLE IN WAY OF INSTABILITY AROUND...SO PRECIPITATION SHOULD BE IN THE FORM OF SHOWERS. HIGH PRESSURE THEN DROPS BACK OVER THE REGION WEDNESDAY NIGHT THROUGH THE END OF THE PERIOD. BELOW NORMAL TEMPERATURES ARE LIKELY THROUGH THE PERIOD WITH HIGHS IN THE 60S...WITH LOW MAINLY IN THE 40S. && .AVIATION... 06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS VFR CIGS/VSBYS EXPECTED TO PERSIST THROUGH 09Z BEFORE MVFR CIGS/VSBYS MOVE NORTH WITH AN ADVANCING WARM FRONT. SCT SHRA ALONG WITH ISOLD -TSRA IS PSBL AT ALL TERMINAL LOCATIONS THROUGH 18Z SATURDAY. WIDESPREAD MVFR CIGS/VSBYS WILL PERSIST WITH OCNL IFR CIGS IN THE KMBG/KABR/KATY TERMINALS AS MOISTURE CONTINUES TO STREAM NORTH BEHIND WARMFRONT. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...HINTZ SHORT TERM...DORN LONG TERM...SD AVIATION...PARKIN WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
615 AM CDT SAT MAY 26 2012 .SHORT TERM...TODAY THROUGH MONDAY NIGHT 337 AM CDT SAT MAY 26 2012 MAIN FORECAST CONCERN IS ON CONVECTIVE EVOLUTION FOR TODAY AND TONIGHT. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED DEEP TROUGHING ALONG THE WEST COAST OF THE U.S. AND STRONG RIDGING BUILDING UP FROM THE LOWER INTO MIDDLE MISSISSIPPI RIVER VALLEY. IN-BETWEEN THE TWO FEATURES...A SUBTROPICAL STREAM OF MOISTURE WITH EMBEDDED WEAK SHORTWAVES IS EVIDENT FROM MEXICO UP INTO IOWA. UNDERNEATH THIS SAME SUBTROPICAL STREAM AREA...A SOUTHWEST 40-50 KT JET EXISTS AT 850MB PER PROFILER DATA...WHICH IS RAPIDLY SENDING MOISTURE AND HEAT NORTHWARD. 00Z RAOBS SHOWED 850MB TEMPS OF 20C OR MORE FROM NEAR TOPEKA KS SOUTHWARD TO THE GULF COAST. COMPARE THESE TO 8C AT MPX AND 15C AT DVN. MOISTURE-WISE... SURFACE DEWPOINTS CURRENTLY RANGE FROM 65 TO 70F NEAR TOPEKA KS SOUTHWARD. THE GRADIENT OF THE 850MB MOISTURE TRANSPORT EXISTS FROM THE NEBRASKA/SOUTH DAKOTA BORDER EASTWARD INTO THE SOUTHERN HALF OF THE FORECAST AREA. CONVERGENCE ALONG THIS GRADIENT HAS BEEN PRODUCING NUMEROUS SHOWERS AND EMBEDDED THUNDERSTORMS. THESE ARE WELL NORTH OF THE MAIN SURFACE WARM FRONT...WHICH EXISTS JUST NORTH OF I-70 IN KANSAS AND MISSOURI. TODAY AND TONIGHT...UPPER TROUGHING ALONG THE WEST COAST IS PROGGED TO SHIFT EAST INTO THE ROCKIES. PERSISTENT WARM ADVECTION DOWNSTREAM WILL HELP TO BUILD THE RIDGING OVER THE MID-MISSISSIPPI RIVER VALLEY NORTHWARD...HELPING ALSO TO BRING THE WARM FRONT NEAR I-70 NORTH. MAIN QUESTION THROUGH TONIGHT IS THE AMOUNT OF CONVECTION WITH THE FRONT. THE CURRENT STREAM OF 850MB MOISTURE TRANSPORT AND GRADIENT IS FORECAST BY ALL MODELS TO WEAKEN SOME THIS MORNING AND SHIFT NORTH ACROSS THE AREA. THE WEAKENING IS LIKELY CAUSED BY THE NORMAL DIURNAL DIMINISHING OF LOW LEVEL JETS. THEREFORE...THINKING THAT THE CURRENT ACTIVITY WILL SLOWLY SHIFT NORTH AND WEAKEN THROUGH THE MORNING. ALSO...AS THE DAY WEARS ON...THERE APPEARS TO BE A SHIFT WESTWARD WITH THE MAIN FOCUS OF 850MB MOISTURE TRANSPORT TOWARDS THE DAKOTAS AND CENTRAL/NORTHERN MINNESOTA. ANOTHER ISSUE OF CONCERN IS THE SUBTROPICAL STREAM AND WEAK EMBEDDED SHORTWAVES WITHIN IT. THIS STREAM SHOULD SHIFT NORTH OVER THE FORECAST AREA DURING THE AFTERNOON. WITH THE SURFACE WARM FRONT LIFTING NORTH INTO NORTHERN IOWA BY 00Z...THIS SITUATION COULD RESULT IN CONVECTIVE DEVELOPMENT. HOWEVER...ANY DEVELOPMENT LOOKS LIKE IT WILL HAVE TO BE ELEVATED BECAUSE SURFACE-BASED PARCELS ARE SUBSTANTIALLY CAPPED (MLCIN PROGGED AT 200 J/KG OR MORE). CONFIDENCE ON THE SHORTWAVES PRODUCING CONVECTION ABOVE THE CAP IS LOW. THERE IS INSTABILITY ABOVE THE CAP...GENERALLY LESS THAN 700 J/KG. SO CANNOT COMPLETELY RULE OUT CONVECTION...BUT WOULD NOT BE SURPRISED EITHER IF IT ENDS UP DRY. SHOULD CONVECTION FIRE ABOVE THE CAP...THE 2-8 KM SHEAR (ESTIMATED EFFECTIVE BULK SHEAR LAYER) IS LESS THAN 30 KT AT BEST. WITH WARM CLOUD DEPTHS BETWEEN 3.5-4 KM...THEREFORE...WOULD ONLY EXPECT GUSTY WINDS AND BRIEF HEAVY RAIN TO BE THE MAIN ISSUES. OVERALL FOR PRECIPITATION CHANCES...KEPT THEM HIGH EARLY THIS MORNING...THEN GRADUAL LOWERING THROUGH THE DAY. FOR TONIGHT...THE 850MB MOISTURE TRANSPORT INCREASES AGAIN...THOUGH THE GRADIENT LOOKS MOSTLY TO THE NORTH FROM ALL MODELS. WILL LEAVE SOME CHANCES...HIGHEST NORTH OF I-90 AS NOTED BY THE 26.00Z NAM/GFS...BUT IT IS ENTIRELY POSSIBLE ANY ACTIVITY ENDS UP NORTH OF OUR AREA TONIGHT AS SUGGESTED BY THE 26.00Z GEM. BELIEVE THE 26.00Z ECMWF IS TOO FAR SOUTH AS IT SUGGESTS QPF PRODUCED ON THE NOSE OF 925MB MOISTURE TRANSPORT...BUT ECMWF SOUNDINGS SUGGEST TOO MUCH CAPPING LIFTED FROM 925 OR 850MB WHERE QPF EXISTS. FOR TEMPERATURES...GENERALLY STAYED CLOSE TO A BLEND OF GUIDANCE. THEY ARE VERY TRICKY TODAY DUE TO CLOUDS...BUT AT THE SAME TIME WARM ADVECTION IN PLACE. HIGH TEMPERATURE IS LIKELY TO OCCUR AT 00Z. SUNDAY...HOT DAY STILL LOOKS ON TAP WITH THE WARM FRONT MOSTLY NORTH OF THE AREA. MAINTAINED A LOW...20 PERCENT...CHANCE OF STORMS IN THE MORNING OVER TAYLOR COUNTY. THIS IS WHERE THE NOSE OF THE 850MB MOISTURE TRANSPORT STILL EXISTS. OTHERWISE...MOSTLY SUNNY CONDITIONS LOOK TO BE THE RULE. 850MB TEMPS OF 20C OR MORE PLUS A BREEZY SOUTHWEST WIND ALL SUPPORT HIGHS CLIMBING INTO THE LOW 90S. SOME LOCATIONS TOO COULD HIT THE MID 90S SINCE DEEP MIXING IS SUGGESTED ON SOUNDINGS. PREVIOUS FORECAST HIGHS SEEM REASONABLE. DEWPOINTS SHOULD FALL THROUGH THE DAY WITH THE MIXING...BUT STAYING UP SOMEWHAT DUE TO RECENT RAIN. SUNDAY NIGHT THROUGH MONDAY NIGHT...TROUGHING OVER THE ROCKIES IS PROGGED TO LIFT NORTHEAST DURING THIS PERIOD...WITH THE CORE OF IT REACHING NORTHWEST ONTARIO AT 12Z TUE. HEIGHT FALLS WITH THIS TROUGH...AND THE ASSOCIATED COLD FRONT...LOOK TO COME ACROSS THE FORECAST AREA LATE SUNDAY NIGHT INTO MONDAY. GOOD CONSENSUS EXISTS THAT A SQUALL LINE WILL FORM ALONG THE COLD FRONT IN THE EASTERN DAKOTAS/WESTERN MINNESOTA SUNDAY EVENING. THIS IS IN AN AREA OF MODERATE INSTABILITY AND 40 KT OF 0-6 KM SHEAR. THE SQUALL LINE SHOULD REACH SOME OF NORTHEAST IOWA...SOUTHEAST MINNESOTA AND NORTHWEST WISCONSIN AFTER MIDNIGHT...WITH ITS SPEED BEING INCREASED SOMEWHAT BY COLD POOL DEVELOPMENT. WHETHER IT IS SEVERE OR NOT BY THE TIME IT GETS TO OUR FORECAST AREA IS A BIG QUESTION...SINCE THE INSTABILITY DECREASES THROUGH THE NIGHT. CERTAINLY THE SHEAR IS PLENTIFUL...BOTH 0-3KM AND 0-6KM...SO IT IS JUST A MATTER OF INSTABILITY. GENERAL CONSENSUS IS THAT THE SQUALL LINE MAY HAVE COMPLETELY DISSIPATED OR BROKEN UP INTO JUST ISOLATED-SCATTERED CONVECTION MONDAY MORNING DUE TO LOSS OF INSTABILITY. AS SUCH...REDUCED CHANCES OF PRECIPITATION FOR 12-18Z MONDAY. AS THE FRONT MOVES INTO THE EASTERN PORTIONS OF THE FORECAST AREA AND INSTABILITY BUILDS...CONVECTION MAY RE-FIRE ON THE FRONT. UNDERSCORE MAY...SEEING THE NEW 26.00Z ECMWF WHICH IS MOSTLY DRY. AGAIN... PLENTY OF SHEAR EXISTS SO POTENTIAL IS THERE FOR SEVERE WEATHER. ANOTHER PROBLEM WITH SEVERE POTENTIAL ON MONDAY IS THAT THE FRONT COULD BE EAST OF THE AREA BY THE TIME STORMS IF THEY FORM TURN SEVERE. WE WILL HAVE TO WAIT AND SEE. DRY SLOT COMES IN BEHIND THE FRONT TO END PRECIPITATION. IT NOW APPEARS ANY PRECIPITATION SHOULD BE EAST OF THE AREA MONDAY NIGHT...THEREFORE...DRIED OUT THE FORECAST MONDAY NIGHT. WARM NIGHT LIKELY ON TAP SUNDAY NIGHT AHEAD OF THE FRONT WITH LOWS NEAR 70. WITH POTENTIAL FOR MORE SUN ON MONDAY AND 850MB TEMPS ONLY DROPPING TO 10-14C AT MOST...HIGHS SHOULD EASILY CLIMB WELL INTO THE 70S AND EVEN LOW TO MID 80S OVER THE EASTERN AREAS AHEAD OF THE FRONT. COOLER NIGHT UNDER MOSTLY CLEAR SKIES ANTICIPATED FOR MONDAY NIGHT. .LONG TERM...TUESDAY THROUGH FRIDAY NIGHT 337 AM CDT SAT MAY 26 2012 AFTER A FAIRLY ACTIVE SHORT TERM PERIOD...THE LONG TERM LOOKS PRETTY QUIET. VERY GOOD MODEL AGREEMENT EXISTS OF SOME FORM OF TROUGHING OVER THE WESTERN GREAT LAKES REGION THROUGHOUT THE REST OF NEXT WEEK. THIS SET UP ALLOWS FOR MUCH OF THE AREA TO BE DOMINATED BY SURFACE HIGH PRESSURE AND A DRY AIR FLOW. MOST OF THE SHORTWAVES SLIDING THROUGH THE NORTHWEST FLOW ALOFT HEAD SOUTHWEST OF THE AREA...A PROBLEM NOTED YESTERDAY. ONE CONCERN TO WATCH OUT FOR IS THE COOLER TEMPERATURES ALOFT AND IF ANY DIURNAL PRECIPITATION CAN FORM. THE 26.00Z ECMWF HINTS AT THIS ON WEDNESDAY...THOUGH ITS PREVIOUS RUN DID NOT. FOR NOW...HAVE FOLLOWED THE CONSENSUS APPROACH WHICH BASICALLY RESULTS IN AN ENTIRELY DRY FORECAST...EXCLUDING A LITTLE LIGHT SHOWER CHANCE ON TUESDAY OVER NORTH CENTRAL WISCONSIN. TEMPERATURES ARE LIKELY TO BE BELOW NORMAL THROUGHOUT DUE TO THE TROUGHING. SOMETHING AGAIN TO WATCH OUT FOR IS ANY CLEAR NIGHTS AND AT SOME OF THE TYPICAL COLD SPOTS FOR POSSIBLE FROST FORMATION. RIGHT NOW...TUESDAY NIGHT AND WEDNESDAY NIGHT WOULD BE THE NIGHTS TO KEEP A CLOSE EYE ON. && .AVIATION...TODAY AND TONIGHT 614 AM CDT SAT MAY 26 2012 SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE EAST OF THE TAF SITES BY 15Z THIS MORNING. VFR CONDITIONS ARE EXPECTED THROUGH THIS AFTERNOON WITH CLOUD BASES IN THE 5 TO 10 KFT RANGE. A WARM FRONT WILL LIFT THROUGH THE AREA THIS AFTERNOON FROM SOUTHERN IOWA...POSSIBLY PRODUCING A FEW SHOWERS AND STORMS. CONFIDENCE LOW ON SHOWERS OR THUNDERSTORMS OCCURRING THIS AFTERNOON AS THE FRONT MOVES IN WITH FORECAST SOUNDINGS SHOWING STRONG CONVECTIVE INHIBITION MOVING OVER THE AREA WITH MUCH WARMER AIR MOVING IN AROUND THE 800 MB LAYER...EFFECTIVELY CAPPING THE ATMOSPHERE FOR THUNDERSTORM DEVELOPMENT. WILL HAVE TO CLOSELY MONITOR THE CAPPING THIS AFTERNOON. IF THE CAP IS WEAKER THAN CURRENT GUIDANCE SUGGESTS...THUNDERSTORMS WILL BE A POSSIBILITY. LOOK FOR SOUTHEAST WINDS TO INCREASE INTO THE 12 TO 16 KT RANGE TODAY WITH GUSTS TO AROUND 25 KTS POSSIBLE. VFR CONDITIONS ARE EXPECTED THIS EVENING THROUGH THE OVERNIGHT HOURS AS THE WARM FRONT LIFTS INTO NORTHERN WISCONSIN/MINNESOTA. FORECAST MODELS ARE HINTING AT LOW LEVEL MOISTURE EDGING INTO THE TAF SITES LATE THIS EVENING INTO THE OVERNIGHT HOURS...POSSIBLY PRODUCING SOME MVFR/IFR CEILINGS. CURRENT THINKING IS THAT THERE WILL BE ENOUGH MIXING/DRYING BEHIND THE WARM FRONT TO INHIBIT LOW CLOUD DEVELOPMENT BUT WILL HAVE TO KEEP A CLOSE WATCH ON THE NEXT SET OF FORECAST MODEL RUNS. && .ARX WATCHES/WARNINGS/ADVISORIES... 337 AM CDT SAT MAY 26 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
337 AM CDT SAT MAY 26 2012 .SHORT TERM...TODAY THROUGH MONDAY NIGHT 337 AM CDT SAT MAY 26 2012 MAIN FORECAST CONCERN IS ON CONVECTIVE EVOLUTION FOR TODAY AND TONIGHT. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED DEEP TROUGHING ALONG THE WEST COAST OF THE U.S. AND STRONG RIDGING BUILDING UP FROM THE LOWER INTO MIDDLE MISSISSIPPI RIVER VALLEY. IN-BETWEEN THE TWO FEATURES...A SUBTROPICAL STREAM OF MOISTURE WITH EMBEDDED WEAK SHORTWAVES IS EVIDENT FROM MEXICO UP INTO IOWA. UNDERNEATH THIS SAME SUBTROPICAL STREAM AREA...A SOUTHWEST 40-50 KT JET EXISTS AT 850MB PER PROFILER DATA...WHICH IS RAPIDLY SENDING MOISTURE AND HEAT NORTHWARD. 00Z RAOBS SHOWED 850MB TEMPS OF 20C OR MORE FROM NEAR TOPEKA KS SOUTHWARD TO THE GULF COAST. COMPARE THESE TO 8C AT MPX AND 15C AT DVN. MOISTURE-WISE... SURFACE DEWPOINTS CURRENTLY RANGE FROM 65 TO 70F NEAR TOPEKA KS SOUTHWARD. THE GRADIENT OF THE 850MB MOISTURE TRANSPORT EXISTS FROM THE NEBRASKA/SOUTH DAKOTA BORDER EASTWARD INTO THE SOUTHERN HALF OF THE FORECAST AREA. CONVERGENCE ALONG THIS GRADIENT HAS BEEN PRODUCING NUMEROUS SHOWERS AND EMBEDDED THUNDERSTORMS. THESE ARE WELL NORTH OF THE MAIN SURFACE WARM FRONT...WHICH EXISTS JUST NORTH OF I-70 IN KANSAS AND MISSOURI. TODAY AND TONIGHT...UPPER TROUGHING ALONG THE WEST COAST IS PROGGED TO SHIFT EAST INTO THE ROCKIES. PERSISTENT WARM ADVECTION DOWNSTREAM WILL HELP TO BUILD THE RIDGING OVER THE MID-MISSISSIPPI RIVER VALLEY NORTHWARD...HELPING ALSO TO BRING THE WARM FRONT NEAR I-70 NORTH. MAIN QUESTION THROUGH TONIGHT IS THE AMOUNT OF CONVECTION WITH THE FRONT. THE CURRENT STREAM OF 850MB MOISTURE TRANSPORT AND GRADIENT IS FORECAST BY ALL MODELS TO WEAKEN SOME THIS MORNING AND SHIFT NORTH ACROSS THE AREA. THE WEAKENING IS LIKELY CAUSED BY THE NORMAL DIURNAL DIMINISHING OF LOW LEVEL JETS. THEREFORE...THINKING THAT THE CURRENT ACTIVITY WILL SLOWLY SHIFT NORTH AND WEAKEN THROUGH THE MORNING. ALSO...AS THE DAY WEARS ON...THERE APPEARS TO BE A SHIFT WESTWARD WITH THE MAIN FOCUS OF 850MB MOISTURE TRANSPORT TOWARDS THE DAKOTAS AND CENTRAL/NORTHERN MINNESOTA. ANOTHER ISSUE OF CONCERN IS THE SUBTROPICAL STREAM AND WEAK EMBEDDED SHORTWAVES WITHIN IT. THIS STREAM SHOULD SHIFT NORTH OVER THE FORECAST AREA DURING THE AFTERNOON. WITH THE SURFACE WARM FRONT LIFTING NORTH INTO NORTHERN IOWA BY 00Z...THIS SITUATION COULD RESULT IN CONVECTIVE DEVELOPMENT. HOWEVER...ANY DEVELOPMENT LOOKS LIKE IT WILL HAVE TO BE ELEVATED BECAUSE SURFACE-BASED PARCELS ARE SUBSTANTIALLY CAPPED (MLCIN PROGGED AT 200 J/KG OR MORE). CONFIDENCE ON THE SHORTWAVES PRODUCING CONVECTION ABOVE THE CAP IS LOW. THERE IS INSTABILITY ABOVE THE CAP...GENERALLY LESS THAN 700 J/KG. SO CANNOT COMPLETELY RULE OUT CONVECTION...BUT WOULD NOT BE SURPRISED EITHER IF IT ENDS UP DRY. SHOULD CONVECTION FIRE ABOVE THE CAP...THE 2-8 KM SHEAR (ESTIMATED EFFECTIVE BULK SHEAR LAYER) IS LESS THAN 30 KT AT BEST. WITH WARM CLOUD DEPTHS BETWEEN 3.5-4 KM...THEREFORE...WOULD ONLY EXPECT GUSTY WINDS AND BRIEF HEAVY RAIN TO BE THE MAIN ISSUES. OVERALL FOR PRECIPITATION CHANCES...KEPT THEM HIGH EARLY THIS MORNING...THEN GRADUAL LOWERING THROUGH THE DAY. FOR TONIGHT...THE 850MB MOISTURE TRANSPORT INCREASES AGAIN...THOUGH THE GRADIENT LOOKS MOSTLY TO THE NORTH FROM ALL MODELS. WILL LEAVE SOME CHANCES...HIGHEST NORTH OF I-90 AS NOTED BY THE 26.00Z NAM/GFS...BUT IT IS ENTIRELY POSSIBLE ANY ACTIVITY ENDS UP NORTH OF OUR AREA TONIGHT AS SUGGESTED BY THE 26.00Z GEM. BELIEVE THE 26.00Z ECMWF IS TOO FAR SOUTH AS IT SUGGESTS QPF PRODUCED ON THE NOSE OF 925MB MOISTURE TRANSPORT...BUT ECMWF SOUNDINGS SUGGEST TOO MUCH CAPPING LIFTED FROM 925 OR 850MB WHERE QPF EXISTS. FOR TEMPERATURES...GENERALLY STAYED CLOSE TO A BLEND OF GUIDANCE. THEY ARE VERY TRICKY TODAY DUE TO CLOUDS...BUT AT THE SAME TIME WARM ADVECTION IN PLACE. HIGH TEMPERATURE IS LIKELY TO OCCUR AT 00Z. SUNDAY...HOT DAY STILL LOOKS ON TAP WITH THE WARM FRONT MOSTLY NORTH OF THE AREA. MAINTAINED A LOW...20 PERCENT...CHANCE OF STORMS IN THE MORNING OVER TAYLOR COUNTY. THIS IS WHERE THE NOSE OF THE 850MB MOISTURE TRANSPORT STILL EXISTS. OTHERWISE...MOSTLY SUNNY CONDITIONS LOOK TO BE THE RULE. 850MB TEMPS OF 20C OR MORE PLUS A BREEZY SOUTHWEST WIND ALL SUPPORT HIGHS CLIMBING INTO THE LOW 90S. SOME LOCATIONS TOO COULD HIT THE MID 90S SINCE DEEP MIXING IS SUGGESTED ON SOUNDINGS. PREVIOUS FORECAST HIGHS SEEM REASONABLE. DEWPOINTS SHOULD FALL THROUGH THE DAY WITH THE MIXING...BUT STAYING UP SOMEWHAT DUE TO RECENT RAIN. SUNDAY NIGHT THROUGH MONDAY NIGHT...TROUGHING OVER THE ROCKIES IS PROGGED TO LIFT NORTHEAST DURING THIS PERIOD...WITH THE CORE OF IT REACHING NORTHWEST ONTARIO AT 12Z TUE. HEIGHT FALLS WITH THIS TROUGH...AND THE ASSOCIATED COLD FRONT...LOOK TO COME ACROSS THE FORECAST AREA LATE SUNDAY NIGHT INTO MONDAY. GOOD CONSENSUS EXISTS THAT A SQUALL LINE WILL FORM ALONG THE COLD FRONT IN THE EASTERN DAKOTAS/WESTERN MINNESOTA SUNDAY EVENING. THIS IS IN AN AREA OF MODERATE INSTABILITY AND 40 KT OF 0-6 KM SHEAR. THE SQUALL LINE SHOULD REACH SOME OF NORTHEAST IOWA...SOUTHEAST MINNESOTA AND NORTHWEST WISCONSIN AFTER MIDNIGHT...WITH ITS SPEED BEING INCREASED SOMEWHAT BY COLD POOL DEVELOPMENT. WHETHER IT IS SEVERE OR NOT BY THE TIME IT GETS TO OUR FORECAST AREA IS A BIG QUESTION...SINCE THE INSTABILITY DECREASES THROUGH THE NIGHT. CERTAINLY THE SHEAR IS PLENTIFUL...BOTH 0-3KM AND 0-6KM...SO IT IS JUST A MATTER OF INSTABILITY. GENERAL CONSENSUS IS THAT THE SQUALL LINE MAY HAVE COMPLETELY DISSIPATED OR BROKEN UP INTO JUST ISOLATED-SCATTERED CONVECTION MONDAY MORNING DUE TO LOSS OF INSTABILITY. AS SUCH...REDUCED CHANCES OF PRECIPITATION FOR 12-18Z MONDAY. AS THE FRONT MOVES INTO THE EASTERN PORTIONS OF THE FORECAST AREA AND INSTABILITY BUILDS...CONVECTION MAY RE-FIRE ON THE FRONT. UNDERSCORE MAY...SEEING THE NEW 26.00Z ECMWF WHICH IS MOSTLY DRY. AGAIN... PLENTY OF SHEAR EXISTS SO POTENTIAL IS THERE FOR SEVERE WEATHER. ANOTHER PROBLEM WITH SEVERE POTENTIAL ON MONDAY IS THAT THE FRONT COULD BE EAST OF THE AREA BY THE TIME STORMS IF THEY FORM TURN SEVERE. WE WILL HAVE TO WAIT AND SEE. DRY SLOT COMES IN BEHIND THE FRONT TO END PRECIPITATION. IT NOW APPEARS ANY PRECIPITATION SHOULD BE EAST OF THE AREA MONDAY NIGHT...THEREFORE...DRIED OUT THE FORECAST MONDAY NIGHT. WARM NIGHT LIKELY ON TAP SUNDAY NIGHT AHEAD OF THE FRONT WITH LOWS NEAR 70. WITH POTENTIAL FOR MORE SUN ON MONDAY AND 850MB TEMPS ONLY DROPPING TO 10-14C AT MOST...HIGHS SHOULD EASILY CLIMB WELL INTO THE 70S AND EVEN LOW TO MID 80S OVER THE EASTERN AREAS AHEAD OF THE FRONT. COOLER NIGHT UNDER MOSTLY CLEAR SKIES ANTICIPATED FOR MONDAY NIGHT. .LONG TERM...TUESDAY THROUGH FRIDAY NIGHT 337 AM CDT SAT MAY 26 2012 AFTER A FAIRLY ACTIVE SHORT TERM PERIOD...THE LONG TERM LOOKS PRETTY QUIET. VERY GOOD MODEL AGREEMENT EXISTS OF SOME FORM OF TROUGHING OVER THE WESTERN GREAT LAKES REGION THROUGHOUT THE REST OF NEXT WEEK. THIS SET UP ALLOWS FOR MUCH OF THE AREA TO BE DOMINATED BY SURFACE HIGH PRESSURE AND A DRY AIR FLOW. MOST OF THE SHORTWAVES SLIDING THROUGH THE NORTHWEST FLOW ALOFT HEAD SOUTHWEST OF THE AREA...A PROBLEM NOTED YESTERDAY. ONE CONCERN TO WATCH OUT FOR IS THE COOLER TEMPERATURES ALOFT AND IF ANY DIURNAL PRECIPITATION CAN FORM. THE 26.00Z ECMWF HINTS AT THIS ON WEDNESDAY...THOUGH ITS PREVIOUS RUN DID NOT. FOR NOW...HAVE FOLLOWED THE CONSENSUS APPROACH WHICH BASICALLY RESULTS IN AN ENTIRELY DRY FORECAST...EXCLUDING A LITTLE LIGHT SHOWER CHANCE ON TUESDAY OVER NORTH CENTRAL WISCONSIN. TEMPERATURES ARE LIKELY TO BE BELOW NORMAL THROUGHOUT DUE TO THE TROUGHING. SOMETHING AGAIN TO WATCH OUT FOR IS ANY CLEAR NIGHTS AND AT SOME OF THE TYPICAL COLD SPOTS FOR POSSIBLE FROST FORMATION. RIGHT NOW...TUESDAY NIGHT AND WEDNESDAY NIGHT WOULD BE THE NIGHTS TO KEEP A CLOSE EYE ON. && .AVIATION... 1135 PM CDT FRI MAY 25 2012 LATEST CONVECTION FROM THE CENTRAL PLAINS INTO SOUTHWEST WI IS BEING DRIVEN BY LOW LEVEL MOISTURE TRANSPORT AND SLOPING FRONTOGENETIC LIFT. MESO MODELS SUGGEST THIS WILL CONTINUE THROUGH THE OVERNIGHT...WITH SOME LIFT NORTH. THE BULK OF THE STRONGER SHRA/TS SHOULD STAY SOUTH OF KRST/KLSE IN THIS SCENARIO...BUT PERIODIC -SHRA WITH ISOLATED TS LOOKS REASONABLE. FORECAST CONFIDENCE AFTER 12Z SAT RATHER SHAKY. THE MODELS PROPOSE A VARIETY OF SOLUTIONS...SOME WITH PERIODS OF TSRA AND SOME DRY. THE WET ONES SEEM TO BANK ON AN UPPER LEVEL SHORTWAVE AND/OR MCV MOVING ACROSS THE AREA LATE THIS MORNING/AFTERNOON...TAPPING INTO ELEVATED INSTABILITY ABOVE A STRONG CAP. OTHERS KEEP ANY SHORTWAVE TROUGH MOSTLY WEST/NORTH...AND THUS KRST/KLSE WOULD BE DRY. FEELING RIGHT NOW IS THE DRIER SOLUTION HAS MORE GOING FOR IT. THE RAP HAS A GOOD HANDLE ON THE PCPN AND FORCING MECHANISMS RIGHT NOW...AND THESE WEAKEN AS THE MOISTURE TRANSPORT/FRONTOGENETIC FORCING LIFTS NORTH TOWARD 12Z. THEN THE FOCUS TURNS TO THE POTENTIAL MCS IN THE PLAINS...WHICH WOULD THEN RIDE INTO CENTRAL MN. SO WITH THIS IN MIND...WITH CONTINUE THE -SHRA VCTS THROUGH ABOUT 12Z FOR KRST/KLSE...WITH VFR CIGS AND MOSTLY UNAFFECTED VSBYS. OF COURSE...ANY DOWN POUR COULD LEAD TO A 2-4SM VSBY...BUT THIS IS EXPECTED TO BE BRIEF IF IT WOULD OCCUR. WINDS WILL BE ON THE INCREASE TODAY...EVENTUALLY BECOMING MORE EAST SOUTHEAST. LOOK FOR HIGHER LATE MORNING/AFTERNOON GUSTS EVEN WITH A SIZABLE INVERSION A LOFT. OBVIOUSLY...SHORT TERM TRENDS WILL HAVE TO BE MONITORED VERY CLOSELY TODAY. && .ARX WATCHES/WARNINGS/ADVISORIES... 337 AM CDT SAT MAY 26 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 PM CDT FRI MAY 25 2012 .SHORT TERM...TONIGHT THROUGH SUNDAY NIGHT 346 PM CDT FRI MAY 25 2012 AT 3 PM...DOPPLER RADAR INDICATED SCATTERED SHOWERS AND THUNDERSTORMS ACROSS NORTHERN IOWA...AND SOUTH-CENTRAL AND SOUTHWEST MINNESOTA. THIS PRECIPITATION IS ASSOCIATED WITH STRONG 600-700 MB FRONTOGENESIS. FURTHER SOUTH ACROSS SOUTHEAST NEBRASKA...SOUTHERN IOWA...AND NORTHERN MISSOURI...THERE IS A MORE ROBUST AREA OF SHOWERS AND THUNDERSTORMS. THIS IS ASSOCIATED WITH STRONG 800 TO 700 MB FRONTOGENESIS. FOR TONIGHT...THE LATEST RAP ALONG WITH SEVERAL OF THE MESO MODELS SUGGEST THAT THE 600-700 MB FRONTOGENESIS WILL SHIFT NORTH TOWARD THE INTERSTATE 90 CORRIDOR THIS EVENING...AND BE LOCATED BETWEEN THE INTERSTATE 90 AND 94 CORRIDOR AFTER MIDNIGHT. THE 800-700 MB FRONTOGENESIS SHIFTS QUICKLY NORTH ACROSS IOWA TONIGHT. THESE FRONTOGENESIS BANDS WILL LIKELY BE THE FOCUS FOR THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. THE BEST INSTABILITY REMAINS TO THE SOUTH AND WEST FOR TONIGHT. AS A RESULT...THE SEVERE WEATHER CHANCES LOOK LOW FOR LATE TONIGHT. ON SATURDAY AND SATURDAY NIGHT...THE MODELS CONTINUE TO SHOW THAT THE AREAS OF ELEVATED BANDS OF FRONTOGENESIS WILL MOVE NORTH ACROSS THE FORECAST AREA. A MODERATE SOUTHERLY FLOW BRINGS MOIST AND UNSTABLE AIR NORTHWARD ACROSS THE REGION. THE 0-3 KM MOST UNSTABLE CAPES GRADUALLY CLIMB DURING THE DAY. BY LATE AFTERNOON...THEY ARE RUNNING 1 TO 3K ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR... AND FROM 3 TO 4K ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. THE SIGNIFICANT TORNADO PARAMETER IS VERY HIGH ACROSS NORTHEAST IOWA AND SOUTHWEST WISCONSIN. HOWEVER...THE BOTH THE SURFACE BASED AND ML CINS INCREASE SO MUCH THAT THE CONVECTION BECOMES ELEVATED. BUFKIT MODEL SOUNDINGS SHOW THAT THE CAPES WILL BE LOCATED ABOVE 10K FEET. WITH THE STORMS BEING SO ELEVATED...THIS ELIMINATES THE SHEAR IN THE LOWEST 3 KILOMETERS WHICH TAKES VERY FAVORABLE BULK SHEAR FOR SUPERCELLS AND MAKES THEM LESS FAVORABLE. TAKING ALL OF THIS INTO ACCOUNT...THINKING THAT THE SEVERE WEATHER THREAT LOOKS TO BE SLIGHT WITH HAIL BEING THE MAIN THREAT. ON SUNDAY...THERE MAY BE A FEW LINGERING SHOWERS AND THUNDERSTORMS ACROSS NORTH-CENTRAL WISCONSIN DURING THE EARLY MORNING...AND THEN MOVES NORTH OF THE AREA. VERY WARM MOVES IN ALOFT. 850 MB TEMPERATURES CLIMB TO AROUND 22C IN THE GFS AND ECMWF...AND TO 24C IN THE NAM/WRF. IF SOILS DO NOT MOISTEN UP SIGNIFICANTLY OVER THE NEXT 36 HOURS...THERE COULD POTENTIALLY BE A VERY STEEP LOW LEVEL LAPSE RATES WHICH WOULD RESULT IN WARMER TEMPERATURES. FOR NOW...WENT WITH THE LOWER AND MID 90S ALONG AND SOUTH OF THE INTERSTATE 94 CORRIDOR...AND NEAR 90 ACROSS NORTH-CENTRAL WISCONSIN. IN ADDITION TO SUNDAYS TEMPERATURES BEING A BIT PROBLEMATIC...THE DEW POINTS MAY ALSO BE AN ISSUE. THE MODELS SUGGEST THAT THERE WILL BE IN THE UPPER 60S. HOWEVER THE BUFKIT MODEL SOUNDINGS SHOW THAT THERE WILL BE A LOT OF DRY AIR ALOFT WHICH HAS BEEN ADVECTED OFF OF THE HIGH PLAINS. MIXING DOWN THIS DRY AIR ALOFT RESULTS IN DEW POINTS IN THE 40S AND 50S. ON SUNDAY NIGHT...THE MODELS CONTINUE TO STRUGGLE ON HOW FAR EAST WILL THE COLD FRONT GET. ALSO THE CAPES MAY BE OVER DONE IF THE DEW POINTS ARE TOO HIGH. WHILE THE INSTABILITY MAY BE IN QUESTION...THE 0-6KM SHEAR IS FAVORABLE FOR THE DEVELOPMENT OF SUPERCELL THUNDERSTORMS. IF SEVERE WEATHER HAPPENED TO DEVELOP...LARGE HAIL AND DAMAGING WINDS WOULD BE THE MAIN CONCERNS. .LONG TERM...MEMORIAL DAY THROUGH FRIDAY 346 PM CDT FRI MAY 25 2012 THE MODELS CONTINUE TO SHOW THAT A STRONG SHORT WAVE TROUGH WILL FLATTEN OUT THE UPPER LEVEL RIDGE ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. AS THIS OCCURS...A STRONG COLD FRONT WILL MOVE EAST ACROSS THE FORECAST AREA ON MEMORIAL DAY. DUE TO CLOUDS AND PRECIPITATION...THE CAPES LOOK TO BE LOW WEST OF THE MISSISSIPPI RIVER. THIS WOULD GREATLY LIMIT THE SEVERE WEATHER POTENTIAL. MEANWHILE FURTHER EAST...SOME MORNING SUNSHINE MAY ALLOW ML CAPES TO CLIMB INTO THE 1 TO 2K RANGE. WITH THIS INSTABILITY AND 0-6 KM SHEAR GREATER THAN 40 KNOTS...A FEW OF THUNDERSTORMS MAY BECOME SEVERE ACROSS WISCONSIN. MAIN THREATS LOOK TO LARGE HAIL... DAMAGING WINDS...AND MAYBE AN ISOLATED TORNADO. && .AVIATION... 1135 PM CDT FRI MAY 25 2012 LATEST CONVECTION FROM THE CENTRAL PLAINS INTO SOUTHWEST WI IS BEING DRIVEN BY LOW LEVEL MOISTURE TRANSPORT AND SLOPING FRONTOGENETIC LIFT. MESO MODELS SUGGEST THIS WILL CONTINUE THROUGH THE OVERNIGHT...WITH SOME LIFT NORTH. THE BULK OF THE STRONGER SHRA/TS SHOULD STAY SOUTH OF KRST/KLSE IN THIS SCENARIO...BUT PERIODIC -SHRA WITH ISOLATED TS LOOKS REASONABLE. FORECAST CONFIDENCE AFTER 12Z SAT RATHER SHAKY. THE MODELS PROPOSE A VARIETY OF SOLUTIONS...SOME WITH PERIODS OF TSRA AND SOME DRY. THE WET ONES SEEM TO BANK ON AN UPPER LEVEL SHORTWAVE AND/OR MCV MOVING ACROSS THE AREA LATE THIS MORNING/AFTERNOON...TAPPING INTO ELEVATED INSTABILITY ABOVE A STRONG CAP. OTHERS KEEP ANY SHORTWAVE TROUGH MOSTLY WEST/NORTH...AND THUS KRST/KLSE WOULD BE DRY. FEELING RIGHT NOW IS THE DRIER SOLUTION HAS MORE GOING FOR IT. THE RAP HAS A GOOD HANDLE ON THE PCPN AND FORCING MECHANISMS RIGHT NOW...AND THESE WEAKEN AS THE MOISTURE TRANSPORT/FRONTOGENETIC FORCING LIFTS NORTH TOWARD 12Z. THEN THE FOCUS TURNS TO THE POTENTIAL MCS IN THE PLAINS...WHICH WOULD THEN RIDE INTO CENTRAL MN. SO WITH THIS IN MIND...WITH CONTINUE THE -SHRA VCTS THROUGH ABOUT 12Z FOR KRST/KLSE...WITH VFR CIGS AND MOSTLY UNAFFECTED VSBYS. OF COURSE...ANY DOWN POUR COULD LEAD TO A 2-4SM VSBY...BUT THIS IS EXPECTED TO BE BRIEF IF IT WOULD OCCUR. WINDS WILL BE ON THE INCREASE TODAY...EVENTUALLY BECOMING MORE EAST SOUTHEAST. LOOK FOR HIGHER LATE MORNING/AFTERNOON GUSTS EVEN WITH A SIZABLE INVERSION A LOFT. OBVIOUSLY...SHORT TERM TRENDS WILL HAVE TO BE MONITORED VERY CLOSELY TODAY. && .ARX WATCHES/WARNINGS/ADVISORIES... 251 PM CDT FRI MAY 25 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM....BOYNE AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
418 AM CDT MON MAY 28 2012 .SHORT TERM... ISSUED AT 319 AM CDT MON MAY 28 2012 (TODAY AND TONIGHT) MAIN CONCERN TODAY WILL BE THE POTENTIAL FOR A FEW SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT. AREA OF SHOWERS AND SCATTERED THUNDERSTORMS OVER WESTERN IOWA SHOULD PROGRESS EASTWARD THIS MORNING. VORT MAX SEEN ON WATER VAPOR IMAGERY OVER CENTRAL NEBRASKA EARLY THIS MORNING SHOULD MOVE NORTHEASTWARD AND WILL SUPPLY LIFT FOR THESE STORMS. ADDITIONAL STORMS MAY DEVELOP AS FAR SOUTH AS NORTHERN MISSOURI AND MOVE INTO NORTHEAST MISSOURI BETWEEN 12-15Z BASED ON LATEST RAP RUN DEPICTING DECENT 925-850MB MOISTURE CONVERGENCE OVER THESE AREAS. CHANCES WILL INCREASE THROUGH THE DAY AS COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS MOVES EASTWARD AND REACHES KUIN-KCOU LINE BY 00Z. MLCAPES BY MID AFTERNOON WILL BE IN THE 1500-2500 J/KG RANGE WITH LIMITED CINH. STILL DOES NOT LOOK LIKE THERE WILL BE MUCH LOW LEVEL CONVERGENCE OR LARGE SCALE ASCENT CAUSE BY A SHORTWAVE TO FORCE WIDESPREAD DEVELOPMENT. SO AREA EXTENT OF STORMS STILL LOOKS TO BE SCATTERED UNLESS COLD POOLS CAN ORGANIZE AND FORCE MORE WIDESPREAD COVERAGE. DEEP LAYER SHEAR STILL ONLY LOOKS TO BE IN THE 25-35 KT RANGE WHICH FAVORS MULTICELLS...THOUGH AMOUNT OF CAPE STILL SUGGEST THE POTENTIAL FOR DAMAGING WIND GUSTS AND SOME LARGE HAIL INTO THE EVENING. COLD FRONT WILL CLEAR THE CWA LATE TONIGHT...SO SHOWERS AND THUNDERSTORMS WILL END FROM NORTHWEST TO SOUTHEAST AFTER MIDNIGHT. TEMPERATURES HAVE MOSTLY BEEN AT OR BELOW FORECAST MOS GUIDANCE THE PAST TWO DAYS...AND DO NOT EXPECT THEM TO EXCEED THESE VALUES TODAY GIVEN MORE CLOUDS. BRITT && .LONG TERM... ISSUED AT 412 AM CDT MON MAY 28 2012 (TUESDAY THROUGH SUNDAY) LOOKS LIKE THE PRECIPITATION SHOULD PUSH SE OF OUR FORECAST AREA BY TUE AS THE COLD FRONT MOVES SE OF THE AREA WITH A SFC RIDGE BUILDING SEWD INTO MO. TEMPERATURES WILL BE COOLER TUE THROUGH WED WITH LOW LEVEL CAA...ALTHOUGH STILL ABOVE NORMAL ON TUE. ELEVATED CONVECTION SHOULD MOVE INTO THE AREA WED NGT AS THE NAM MODEL DEPICTS STRONG 850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE OVER CNTRL MO ON NOSE OF S-SWLY LOW LEVEL JET. MODELS SHOWING A GOOD CHANCE OF WIDESPREAD SHOWERS AND STORMS ON THU AS AN UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE EWD THROUGH THE REGION. THE GFS MODEL IS FURTHER S WITH THE MAIN UPPER LEVEL LOW VERSUS THE ECMWF SOLUTION AND IS ALSO LESS PROGRESSIVE WITH THE UPPER LEVEL LOW AND ASSOCIATED PRECIPITATION. FOR NOW WILL GO WITH THE MORE PROGRESSIVE ECMWF SOLUTION WHICH APPEARS MORE REALISTIC FOR THIS TIME OF YEAR AND MORE LIKELY TOO VERIFY THAN THE GFS. WILL END THE POPS OR LOWER THEM DRAMATICALLY BY FRI AS THE UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE E OF OUR AREA. TEMPERATURES WILL BE COLDER AND BELOW NORMAL ON THU MAINLY DUE TO CLOUDS AND PRECIPITATION AND CONTINUED RELATIVELY COLD THU NGT AND FRI WITH NLY WINDS BRINGING COLDER AIR INTO THE REGION BEHIND THE 850MB/SFC LOW. THE ECMWF MODEL DROPS THE 4 DEGREE C 850 MB ISOTHERM SWD TO STL BY 12Z FRI. TEMPERATURES WILL BEGIN TO MODERATE THIS WEEKEND AS UPPPER LEVE HEIGHTS RISE BEHIND THE UPPER LEVEL TROUGH AND THE LOW LEVEL WINDS BECOME MORE S-SWLY BEHIND THE SFC RIDGE. GKS && .AVIATION... ISSUED AT 1132 PM CDT SUN MAY 27 2012 VFR CONDITIONS TO CONTINUE THROUGH FORECAST PERIOD. MAIN ISSUE CONTINUES TO BE THE WINDS. SOUTH WINDS TO PERSIST EARLY THIS MORNING ...THEN VEER TO THE SOUTHWEST AHEAD OF A COLD FRONT BY MID MORNING TODAY. WILL SEE WINDS MIX DOWN TO SURFACE...SO EXPECT GUSTS TO NEAR 25KTS AT TIMES. MODELS SHOW SOME PREFRONTAL ACTIVITY FIRING BY LATE MORNING...MAINLY FOR KUIN AND KCOU...SO ADDED VCNTY SHOWER MENTION...AS THERE IS STILL SOME UNCERTAINTY ON TIMING AND COVERAGE OF ACTIVITY WITH THIS SYSTEM. THEN WINDS DIMINISH TOWARDS SUNSET WITH SOME SHOWERS/STORMS POSSIBLE IN METRO AREA AFTER 02Z...SO ADDED VCNTY SHOWER MENTION. FRONT TO SLOWLY MAKE ITS WAY THROUGH AREA LATE THIS EVENING...AFTER 04Z TUESDAY. SPECIFICS FOR KSTL...VFR CONDITIONS TO CONTINUE THROUGH FORECAST PERIOD. MAIN ISSUE CONTINUES TO BE THE WINDS. SOUTH WINDS TO PERSIST EARLY THIS MORNING...THEN VEER TO THE SOUTHWEST AHEAD OF A COLD FRONT BY 15Z TODAY. WILL SEE WINDS MIX DOWN TO SURFACE...SO EXPECT GUSTS TO NEAR 25KTS AT TIMES. MODELS KEEP ANY PREFRONTAL ACTIVITY NORTH OF METRO AREA DURING THE DAY. THEN WINDS DIMINISH TOWARDS SUNSET WITH SOME SHOWERS/STORMS POSSIBLE IN METRO AREA AFTER 02Z...SO ADDED VCNTY SHOWER MENTION. FRONT TO SLOWLY MAKE ITS WAY THROUGH METRO AREA...AFTER 07Z TUESDAY. BYRD && .CLIMATE... ISSUED AT 653 PM CDT MON MAY 21 2012 HERE IS A LIST OF RECORD HIGH TEMPERATURES FOR MONDAY... ...MONDAY... (5/28) ST. LOUIS 93 2006 COLUMBIA 91 2006 QUINCY 94 1914 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
321 AM CDT MON MAY 28 2012 .SHORT TERM... ISSUED AT 319 AM CDT MON MAY 28 2012 (TODAY AND TONIGHT) MAIN CONCERN TODAY WILL BE THE POTENTIAL FOR A FEW SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT. AREA OF SHOWERS AND SCATTERED THUNDERSTORMS OVER WESTERN IOWA SHOULD PROGRESS EASTWARD THIS MORNING. VORT MAX SEEN ON WATER VAPOR IMAGERY OVER CENTRAL NEBRASKA EARLY THIS MORNING SHOULD MOVE NORTHEASTWARD AND WILL SUPPLY LIFT FOR THESE STORMS. ADDITIONAL STORMS MAY DEVELOP AS FAR SOUTH AS NORTHERN MISSOURI AND MOVE INTO NORTHEAST MISSOURI BETWEEN 12-15Z BASED ON LATEST RAP RUN DEPICTING DECENT 925-850MB MOISTURE CONVERGENCE OVER THESE AREAS. CHANCES WILL INCREASE THROUGH THE DAY AS COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS MOVES EASTWARD AND REACHES KUIN-KCOU LINE BY 00Z. MLCAPES BY MID AFTERNOON WILL BE IN THE 1500-2500 J/KG RANGE WITH LIMITED CINH. STILL DOES NOT LOOK LIKE THERE WILL BE MUCH LOW LEVEL CONVERGENCE OR LARGE SCALE ASCENT CAUSE BY A SHORTWAVE TO FORCE WIDESPREAD DEVELOPMENT. SO AREA EXTENT OF STORMS STILL LOOKS TO BE SCATTERED UNLESS COLD POOLS CAN ORGANIZE AND FORCE MORE WIDESPREAD COVERAGE. DEEP LAYER SHEAR STILL ONLY LOOKS TO BE IN THE 25-35 KT RANGE WHICH FAVORS MULTICELLS...THOUGH AMOUNT OF CAPE STILL SUGGEST THE POTENTIAL FOR DAMAGING WIND GUSTS AND SOME LARGE HAIL INTO THE EVENING. COLD FRONT WILL CLEAR THE CWA LATE TONIGHT...SO SHOWERS AND THUNDERSTORMS WILL END FROM NORTHWEST TO SOUTHEAST AFTER MIDNIGHT. TEMPERATURES HAVE MOSTLY BEEN AT OR BELOW FORECAST MOS GUIDANCE THE PAST TWO DAYS...AND DO NOT EXPECT THEM TO EXCEED THESE VALUES TODAY GIVEN MORE CLOUDS. BRITT && .AVIATION... ISSUED AT 1132 PM CDT SUN MAY 27 2012 VFR CONDITIONS TO CONTINUE THROUGH FORECAST PERIOD. MAIN ISSUE CONTINUES TO BE THE WINDS. SOUTH WINDS TO PERSIST EARLY THIS MORNING ...THEN VEER TO THE SOUTHWEST AHEAD OF A COLD FRONT BY MID MORNING TODAY. WILL SEE WINDS MIX DOWN TO SURFACE...SO EXPECT GUSTS TO NEAR 25KTS AT TIMES. MODELS SHOW SOME PREFRONTAL ACTIVITY FIRING BY LATE MORNING...MAINLY FOR KUIN AND KCOU...SO ADDED VCNTY SHOWER MENTION...AS THERE IS STILL SOME UNCERTAINTY ON TIMING AND COVERAGE OF ACTIVITY WITH THIS SYSTEM. THEN WINDS DIMINISH TOWARDS SUNSET WITH SOME SHOWERS/STORMS POSSIBLE IN METRO AREA AFTER 02Z...SO ADDED VCNTY SHOWER MENTION. FRONT TO SLOWLY MAKE ITS WAY THROUGH AREA LATE THIS EVENING...AFTER 04Z TUESDAY. SPECIFICS FOR KSTL...VFR CONDITIONS TO CONTINUE THROUGH FORECAST PERIOD. MAIN ISSUE CONTINUES TO BE THE WINDS. SOUTH WINDS TO PERSIST EARLY THIS MORNING...THEN VEER TO THE SOUTHWEST AHEAD OF A COLD FRONT BY 15Z TODAY. WILL SEE WINDS MIX DOWN TO SURFACE...SO EXPECT GUSTS TO NEAR 25KTS AT TIMES. MODELS KEEP ANY PREFRONTAL ACTIVITY NORTH OF METRO AREA DURING THE DAY. THEN WINDS DIMINISH TOWARDS SUNSET WITH SOME SHOWERS/STORMS POSSIBLE IN METRO AREA AFTER 02Z...SO ADDED VCNTY SHOWER MENTION. FRONT TO SLOWLY MAKE ITS WAY THROUGH METRO AREA...AFTER 07Z TUESDAY. BYRD && .CLIMATE... ISSUED AT 653 PM CDT MON MAY 21 2012 HERE IS A LIST OF RECORD HIGH TEMPERATURES FOR MONDAY... ...MONDAY... (5/28) ST. LOUIS 93 2006 COLUMBIA 91 2006 QUINCY 94 1914 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1246 AM CDT MON MAY 28 2012 .AVIATION...06Z KGRI TAF. SHOWERS AND THUNDERSTORMS THAT DEVELOPED ALONG A FRONTAL BOUNDARY PUSHING THROUGH THE REGION HAVE FINALLY BEGUN TO DISSIPATE ACROSS THE REGION. THE TAF SITE MIGHT STILL SEE A FEW LIGHT SHOWERS AND A ROGUE LIGHTNING STRIKE OR TWO FOR THE NEXT FEW HOURS...BUT PRECIPITATION SHOULD BEGIN TO COME TO AN END BY ABOUT 9Z. CLOUD BASES ARE ALSO EXPECTED TO LIFT AS SHOWERS PUSH OUT OF THE REGION. WITH SHOWERS IN THE AREA...WINDS WILL LIKELY FLUCTUATE AROUND THE NORTH DIRECTION BEFORE TURNING MORE NORTHWEST THROUGH THE MORNING HOURS...AND FINALLY WEST TO SOUTHWEST BY THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 811 PM CDT SUN MAY 27 2012/ UPDATE...WINDS HAVE DIMINISHED WITH THE EXCEPTION OF NEAR THUNDERSTORMS. HAVE LET THE WIND ADVISORY EXPIRE. THE REMAINDER OF THE FORECAST IS IN GOOD SHAPE AT THIS TIME. PREV DISCUSSION... /ISSUED 324 PM CDT SUN MAY 27 2012/ SHORT TERM...THIS AFTERNOON THROUGH MONDAY. OVERALL VERY LITTLE NOTABLE CHANGE TO THE INHERITED FORECAST THROUGH THE NEXT 24-30 HOURS...WITH THE OBVIOUS MAIN ISSUE BEING THE LIKELY ROUND OF SEVERE THUNDERSTORMS/HEAVY RAINFALL LATE THIS AFTERNOON INTO TONIGHT. 18Z OBJECTIVE SURFACE ANALYSIS PAINTS A WEAK 1002 MB LOW NEAR HILL CITY KS...WITH A SOMEWHAT ILL-DEFINED COLD FRONT EXTENDING NORTH FROM THE LOW ACROSS FAR WEST/NORTHWEST PORTIONS OF THE CWA. FARTHER EAST...THE MAJORITY OF THE CWA IS SOLIDLY IN THE SOUTHERLY WIND REGIME AHEAD OF THE BOUNDARY...WITH SUSTAINED SPEEDS MAINLY 15-25 MPH AND GUSTS UP TO 35 MPH. HOWEVER...KS ZONES ARE AVERAGING A BIT STRONGER SPEEDS...WITH SUSTAINED CLOSER TO 30 MPH AND GUSTS TO AROUND 40 MPH. ALTHOUGH WINDS ARE CURRENTLY STRUGGLING TO REACH ADVISORY CRITERIA DOWN THERE...ANTICIPATE A POSSIBLE SLIGHT INCREASE AS THE AFTERNOON WEARS ON...AND THUS WILL LET THE INHERITED WIND ADVISORY CONTINUE AS-IS FOR NOW ALTHOUGH AN EARLY CANCELLATION IS NOT OUT OF THE QUESTION. TEMP WISE...EARLIER NUDGED UP AFTERNOON HIGHS 1-2 DEGREES FROM PREVIOUS FORECAST IN MOST AREAS...RANGING FROM MID 80S WEST TO LOW 90S EAST AND SOUTH. SO FAR...THIS SEEMS TO BE ON TRACK...DESPITE THE FAIRLY WIDESPREAD CUMULUS FIELD WHICH AS OVERTAKEN MOST OF THE CWA. ALOFT...WATER VAPOR IMAGERY AND SHORT TERM MODEL DATA CLEARLY REVEALS THE PRIMARY EXPANSIVE SHORTWAVE OF INTEREST APPROACHING FROM THE CENTRAL PLAINS...AND ANCHORED BY A CLOSED 500MB LOW PUSHING ACROSS EASTERN MT. THE PRIMARY 300MB JET AXIS AROUND 100KT IS STILL TO THE WEST...EXTENDING NORTH-SOUTH FROM WESTERN NEB INTO SD. RADAR WISE...THERE HAVE BEEN A SMATTERING OF HIGH BASED SHOWERS/MAYBE A FEW VERY WEAK THUNDERSTORMS MIGRATING NORTHEAST ACROSS CENTRAL/EASTERN COUNTIES DURING THE PAST SEVERAL HOURS...LIKELY AMOUNTING TO NOTHING MORE THAN A GLORIFIED SPRINKLE. GETTING TO THE FORECAST...THE WELL-ADVERTISED AFTERNOON/EVENING ROUND OF SEVERE THUNDERSTORMS IS THE PARAMOUNT CONCERN. LITTLE CHANGE IN THINKING/MODEL TRENDS HAS OCCURRED THUS FAR FROM THE INHERITED OVERNIGHT FORECAST...WHICH REALLY SEEMED TO HAVE A GOOD HANDLE ON THINGS. ALSO AGREE WITH LATEST SPC DAY 1 CONVECTIVE OUTLOOK EMPHASIZING THE HAIL/WIND THREAT BUT KEEPING THE TORNADO POTENTIAL MORE IN CHECK. ONE TREND THAT HAS SEEMED TO EMERGE TODAY IS SLIGHTLY LOWER INSTABILITY VALUES...WITH THE RAP/RUC ADVERTISING 0-1 KM MLCAPE VALUES TOPPING OUT MAINLY AROUND 1500 J/KG INSTEAD OF MORE WIDESPREAD 2000 J/KG. HOWEVER...WITH 0-6KM DEEP LAYER SHEAR VALUES CURRENTLY INCREASING INTO THE 40-60KT RANGE FROM WEST TO EAST AS THE SHORTWAVE APPROACHES...AND MID LEVEL TEMPS GRADUALLY COOLING AS WELL...SHOULD STILL SEE A ROBUST SEVERE THREAT. LEANING TOWARD THE LATEST RAP/RUC AND HRRR FOR THE DETAILS...THE 21Z-00Z TIME FRAME SHOULD FEATURE THE ONSET OF STRONG/SEVERE CONVECTION...MAINLY ACROSS THE WESTERN 1/2 OF THE CWA. AS A RESULT...LOWERED POPS A BIT IN EASTERN ZONES THROUGH 00Z...KEEPING SEVERAL COUNTIES BELOW LIKELY WORDING. ONCE STORMS FORM...A POTENTIALLY MESSY MIX OF INITIALLY DISCRETE CELLS AND QUASI-LINEAR SEGMENTS SHOULD UNFOLD...WITH INDIVIDUAL ELEMENTS TRACKING NORTHEAST AROUND 35 MPH. WITH SURFACE DEWPOINT DEPRESSIONS ON THE ORDER OF 20-30 DEGREES...AND RESULTANT LCL HEIGHTS LARGELY IN EXCESS OF 1500-2000M TO START OUT WITH...THINK THAT INITIAL STORMS SHOULD BE MAINLY HAIL/EFFICIENT WIND PRODUCERS...POSSIBLY PRODUCING ANOTHER ROUND OF GUSTNADOES AS SEEN BACK ON THE 19TH. HOWEVER...AS LONG AS STORMS CAN REMAIN AT LEAST QUASI-DISCRETE TOWARD 00Z AND TOWARD SUNSET...PARAMETERS DO BECOME A BIT MORE FAVORABLE FOR MAYBE A FEW TORNADOES...WITH BOUNDARY LAYER COOLING BRINGING LCLS DOWN CLOSER TO 1000M AND 0-1KM BULK SHEAR INCREASING TO AROUND 20-25KT AND 0-1KM SRH POSSIBLY EXCEEDING 150 M2/S2...AT LEAST FOR A FEW HOURS. THIS IS PARTIALLY IN RESPONSE TO SURFACE WINDS SLIGHTLY BACKING IN RESPONSE TO THE LOW DEEPENING A BIT TO AROUND 997MB IN NORTHWEST/NORTH CENTRAL KS. FOR TORNADO POTENTIAL...SO MUCH WILL DEPEND ON YET-TO-BE-RESOLVED DETAILS IN STORM MODE/STORM INTERACTION...BUT OVERALL THE ENVIRONMENT SHOULD NOT SUPPORT ANYTHING LONG TRACK OR PARTICULARLY STRONG. AS FOR HAIL...WILL LEAVE POTENTIAL FOR UP TO BASEBALL WORDING IN THE HWO...BUT WITH INSTABILITY NOT EYE-POPPING WOULD TEND TO THINK MOST SHOULD REMAIN GOLF BALL OR SMALLER. CERTAINLY WIND GUSTS TO AT LEAST 70 MPH ARE A CONCERN. SPECIFICALLY GETTING INTO THE EVENING 00Z-06Z PERIOD...KEPT 60-80 POPS GOING ACROSS MAINLY THE EASTERN HALF OF THE CWA...BUT EXPANDED AT LEAST SLIGHT POPS ALL THE WAY BACK ACROSS THE FAR WEST...AS THE COLD FRONTAL INVASION APPEARS TO BE A BIT SLOWER THAN PREVIOUSLY THOUGHT...AS IT STALLS OUT IN RESPONSE TO A GRADUAL DEEPENING OF THE NORTHWEST KS SURFACE LOW TO AROUND 997MB. THAT BEING SAID...THERE WILL LIKELY STILL BE SHARP EAST-WEST GRADIENT BETWEEN STORMS AND NO STORMS...AND SEVERAL WESTERN COUNTIES COULD MISS OUT ON MOST IF NOT ALL THE ACTION. LOCALLY HEAVY RAIN POTENTIAL WILL INCREASE THIS EVENING AS WELL...AS STORMS LIKELY BECOME MORE LINEAR AND THE 850MB LOW LEVEL JET ACCELERATES MOISTURE TRANSPORT INTO AND OVER THE INVADING LOW LEVEL FRONTAL ZONE. SHOULD EASILY SEE SOME FAIRLY WIDESPREAD 1-2 INCH AMOUNTS...WITH LOCALIZED 2+ QUITE POSSIBLE AS WELL IF THINGS STALL OUT AND/OR BACKBUILD FOR A FEW HOURS THIS EVENING AS HINTED BY THE 12Z 4KM WRF-NMM EXPLICIT REFLECTIVITY. FOR THE LATE NIGHT 06Z-12Z PERIOD...MAIN CHANGE WAS TO INCREASE POPS ACROSS EASTERN ZONES DURING THE 06Z-09Z PERIOD...BUT KEPT THEM BELOW LIKELY RANGE AT LEAST FOR NOW. BOTH THE 12Z NAM/4KM WRF SUPPORT LINGERING CONVECTION FOR AT LEAST A FEW HOURS PAST 06Z ESPECIALLY IN SOUTHEAST COUNTIES. CONFIDENCE IS RATHER HIGH IN STORM-FREE CONDITIONS POST-09Z...AS DRIER AIR INVADES BEHIND THE PASSING COLD FRONT. KEPT LOW TEMPS TONIGHT SIMILAR TO PREVIOUS...RANGING FROM LOW 50S FAR WEST TO LOW 60S FAR EAST. GETTING INTO MONDAY...OTHER THAN BEING A BIT BREEZY...A PLEASANT MEMORIAL DAY HOLIDAY IS IN STORE. ALOFT...THE PARENT 500MB CLOSED LOW WILL SLOWLY MIGRATE FROM THE MT/ND BORDER TO EASTERN ND...WHILE AT THE SURFACE...THE COLD FRONT TRACKS WELL OFF TO THE SOUTH AND EAST...ALIGNED FROM NORTHERN IL TO NEAR THE KS/OK BORDER BY LATE AFTERNOON. MUCH DRIER AND SOMEWHAT COOLER AIR WILL ARRIVE IN THE WAKE OF THIS BOUNDARY...RESULTING IN SUNNY/MOSTLY SUNNY SKIES. CHANGED HIGH TEMPS LITTLE FROM PREVIOUS FORECAST...KEEPING THEM CLOSE TO 12Z MET GUIDANCE RANGING FROM MID-UPPER 70S NORTHWEST TO MAINLY MID 80S SOUTHEAST. HOWEVER FAR SOUTHEAST AROUND BELOIT COULD STILL REACH UPPER 80S. LOWERED DEWPOINTS A FEW DEGREES FROM PREVIOUS FORECAST...AND POSSIBLY NOT ENOUGH...AS NAM-BASED MIX-DOWN TOOLS SUGGEST DEWPOINTS COULD PLUNGE ALL THE WAY INTO THE 20S IN SOUTH/WEST AREAS AS BOUNDARY LAYER MIXING INCREASES TO AROUND 700MB. NOT GOING TO GO QUITE THIS LOW YET...BUT STILL HAVE MOST OF THE CWA MIXING WELL DOWN INTO THE 30S FOR DEWPOINTS. FORTUNATELY WILL NOT HAVE TO CONSIDER A RED FLAG WARNING AS OFFICIAL VEGETATIVE FUEL STATUS IS STILL DEEMED UNFAVORABLE FOR FIRE GROWTH...BUT RH VALUES SHOULD NONETHELESS DIVE BELOW 20 PERCENT ACROSS AT LEAST THE SOUTHWEST 1/2 OF THE CWA. THE AFOREMENTIONED DEEP MIXING WILL ALSO KICK UP WESTERLY WINDS DURING THE DAY...WITH SUSTAINED SPEEDS EASILY 15-20 MPH FOR SEVERAL HOURS AND GUSTING TO AROUND 25 MPH. LONG TERM...MONDAY NIGHT THROUGH SUNDAY. MAIN FORECAST CONCERNS WILL BE THUNDERSTORM CHANCES AND TEMPERATURES. A SURFACE HIGH BUILDS INTO THE FORECAST AREA MONDAY NIGHT INTO TUESDAY. TEMPERATURES WILL BE A LITTLE COOLER AS THE TEMPERATURES AT 850MB DECREASE DURING THE DAY. BY TUESDAY NIGHT AN UPPER LEVEL WAVE STARTS TO MOVE INTO THE PLAINS. THIS WILL BRING A CHANCE FOR THUNDERSTORMS TO THE AREA. THE WAVE STRENGTHENS AS IT MOVES INTO THE AREA WEDNESDAY AND WEDNESDAY NIGHT. THE BEST CAPE IS GOING TO BE WEDNESDAY AFTERNOON AND DECREASES AFTER THAT. THERE COULD BE SOME STRONG THUNDERSTORMS DURING THE AFTERNOON BUT WITH THE CAPE DECREASING LATER...EXPECT THAT THUNDERSTORMS WILL BECOME MORE ISOLATED DURING THE EVENING. WITH CLOUDS AND PRECIPITATION AROUND ON WEDNESDAY EXPECT TEMPERATURES TO BE A BIT COOLER THAN RECENTLY. THE SHOWERS AND ISOLATED THUNDERSTORMS CONTINUE ON THURSDAY WHEN THE UPPER WAVE FINALLY MOVES TO THE EAST. TEMPERATURES WILL REMAIN ON THE COOLER SIDE FOR THURSDAY. THURSDAY NIGHT INTO FRIDAY WILL BE DOMINATED BY ANOTHER SURFACE HIGH PRESSURE AREA THAT SETTLES INTO THE AREA. BY FRIDAY NIGHT THE SURFACE HIGH MOVES OFF TO THE EAST AND WINDS TURN TO THE SOUTH. A COUPLE OF WEAK UPPER LEVEL WAVES MOVE INTO THE AREA FOR THE PERIOD SATURDAY INTO SUNDAY. EXPECT SOME SLIGHT CHANCES FOR SHOWERS AND THUNDERSTORMS WITH SPOTTY PRECIPITATION. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
1230 AM CDT MON MAY 28 2012 .AVIATION... VFR IS EXPECTED ALL AREAS TONIGHT THROUGH MONDAY EVENING. MIDLEVEL CLOUD DECK AND SPRINKLES EAST OF HIGHWAY 83 ARE EXPECTED TO LIFT NORTH OVERNIGHT LEAVING JUST SCATTERED TO PERHAPS BROKEN MID LEVEL CLOUDINESS ON MONDAY. && .PREV DISCUSSION... /ISSUED 811 PM CDT SUN MAY 27 2012/ UPDATE... STRONG MOISTURE TRANSPORT HAS SHIFTED EAST OUT OF THE FCST AREA. STILL SOME WEAK TRANSPORT JUST AHEAD OF A MIDLEVEL COLD FRONT LOCATED ACROSS WRN HOLT AND CUSTER COUNTIES. SO...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE. NOTE THE HRRR IS CLEARING THE FCST AREA OF CONVECTION BY 04Z. THIS SEEMS REASONABLE. THE FCST HAS BEEN UPDATED FOR SCATTERED SHOWERS AND ISOLATED TSTMS VS THE PREVIOUS LIKELY POP FCST. PREV DISCUSSION... /ISSUED 621 PM CDT SUN MAY 27 2012/ UPDATE... AVIATION... VFR IS EXPECTED MOST AREAS TONIGHT AND MONDAY. A NARROW CORRIDOR OF SCATTERED STRONG THUNDERSTORMS FROM STOCKVILLE NORTHEAST THROUGH ONEILL SHOULD WEAKEN THIS EVENING AS A COLD FRONT MOVES SLOWLY EAST THROUGH ERN NEB. DRY AIR SHOULD FILL IN BEHIND THIS FRONT BY 04Z AT THE LATEST ACCORDING THE HRRR MODEL WHICH HAS BEEN VERIFYING THIS EVENING. PREV DISCUSSION... /ISSUED 330 PM CDT SUN MAY 27 2012/ SYNOPSIS... ANALYSIS OF THE 19Z MSL DATA SHOWED A BOUNDARY OR FRONT FROM NORTHEAST NEBRASKA TO A LOW ALONG THE KANSAS-NEBRASKA BORDER EAST OF MCCOOK AND TO ANOTHER LOW IN SOUTHEAST COLORADO. ANOTHER BOUNDARY OR FRONT EXTENDED TO A LOW IN SOUTHEAST NORTH DAKOTA. OPEN CELLED CUMULUS ALONG AND SOUTHEAST OF THE FRONT OVER NORTHEAST TO SOUTH CENTRAL NEBRASKA SHOWED THE AREAS OF GREATEST INSTABILITY. ANOTHER SMALL FIELD OF CUMULUS IN CENTRAL AND NORTH CENTRAL NEBRASKA HINTED AT SOME ELEVATED INSTABILITY. THERE WERE ALSO CUMULUS CLOUDS IN THE NEBRASKA PANHANDLE AND NORTHEAST COLORADO FROM ABOUT PINE RIDGE AND WHITECLAY TO STERLING. DERIVED IMAGERY FROM GOES SATELLITE SHOWED THE MOST UNSTABLE CONDITIONS AND ABUNDANT PRECIPITABLE WATER IN NORTHEAST THROUGH SOUTH CENTRAL NEBRASKA. DISCUSSION... THE FORECAST CHALLENGE CONTINUES TO BE TIMING...EXTENT AND STRENGTH OF CONVECTION IN THIS FAIRLY FLUID PATTERN. MODELS ARE IN DECENT AGREEMENT FOR THE EARLIEST PARTS OF THE FORECAST. SHORT TERM...TONIGHT THROUGH TUESDAY. ANY OF THE CUMULUS FIELDS WOULD BE FAVORABLE FOR ADDITIONAL CONVECTIVE DEVELOPMENT. FOR THE NORTH PLATTE FORECAST AREA... THE AREA MOST FAVORABLE FOR SEVERE THUNDERSTORMS WOULD BE WHEELER AND GARFIELD COUNTIES AND THE EASTERN PARTS OF HOLT AND CUSTER COUNTIES WHERE THE MAIN SURFACE BOUNDARY IS. INDEED...THE HOURLY RAPID REFRESH INDICATES JUST THAT. ISOLATED CONVECTION COULD DEVELOP IN THE PANHANDLE AS WELL. AFTER MIDNIGHT...THUNDERSTORMS MOVE INTO EASTERN NEBRASKA AS HIGH PRESSURE COMES IN FROM THE NORTHWEST. TEMPERATURES TUESDAY WILL BE COOLER THAN THEY ARE TODAY. BREEZY CONDITIONS CAN BE EXPECTED DURING THE DAY TUESDAY WITH THE WIND COMING AROUND TO THE WEST. LONG TERM...TUESDAY NIGHT THROUGH SUNDAY. AS THE LEE SIDE TROUGH REDEVELOPS TUESDAY NIGHT...LOW LEVEL FLOW FROM THE SOUTH TO SOUTHEAST RETURNS AND BRINGS SOME MOISTURE INTO WESTERN NEBRASKA (PRECIPITABLE WATER 0.50-0.75 INCH). AS A FRONT PIVOTS THROUGH WESTERN NEBRASKA...THE MOIST AIR WILL BE LIFTED UP AND COULD PRODUCE FAIRLY WIDESPREAD PRECIPITATION WEDNESDAY. WITH SURFACE-BASED AND ELEVATED LIFTED INDICES BELOW ZERO C... THUNDERSTORMS WILL BE THE MOST LIKELY FORM OF PRECIPITATION THAT DOES DEVELOP. IT APPEARS THAT 30-50 PERCENT PROBABILITY IS A REASONABLE FORECAST AT THIS TIME. LATER IN THE FORECAST...THE LEE SIDE TROUGH BEGINS TO FORM AGAIN SATURDAY AND SETS THE SCENE FOR PRECIPITATION AGAIN SUNDAY OR MONDAY AS THE ATMOSPHERE DESTABILIZES. HOWEVER...THERE IS A LOT OF UNCERTAINTY REGARDING THE TIMING AND WE WILL NOT INCLUDE MORE THAN A SLIGHT CHANCE OF PRECIPITATION IN THE FORECAST. AFTER THE FRONT...HIGH TEMPERATURES WEDNESDAY THROUGH FRIDAY WILL BE IN THE 60S IN NORTHERN NEBRASKA AND IN THE 70S IN SOUTH CENTRAL AND SOUTHWEST NEBRASKA. FIRE WEATHER... COLD FRONT THAT MOVED ACROSS WESTERN NEBRASKA LAST NIGHT HAS BROUGHT DRYING WESTERLY WINDS TO WESTERN NEBRASKA TODAY. TEMPERATURES ARE IN THE 70S WHILE DEW PTS ARE IN THE 20S AND 30S. THIS COMBINATION HAS PUSHED PORTIONS OF WESTERN NEBRASKA TO SEE RH VALUES DROP TO AND BELOW 15 PERCENT. WINDS ARE COMPLEX WITH GENERALLY WESTERLY WINDS IN THE 15 TO 25 MPH RANGE. THUS MARGINAL CRITICAL FIRE WX CONDITIONS EXPERIENCED AND EXPECT THEM TO CONTINUE...THUS NO CHANCE TO THE ONGOING RED FLAG WARNING. TOMORROW SLIGHTLY COOLER TEMPS WITH SIMILAR DEW PTS SHOULD RESULT IN MINIMUM RH VALUES CLOSER TO 20 PERCENT. WESTERLY WINDS OF 15 TO 25 MPH ARE ANTICIPATED AN MAYBE CLOSER TO 30 MPH. THUS A HIGH FIRE DANGER WILL EXIST FOR TOMORROW...HOWEVER WITH THE RH PERCENTAGES EXPECTED TO REMAIN ABOVE THE CRITICAL 15 PERCENT...NO HEADLINE EXPECTED...HOWEVER WILL MONITOR CLOSELY. && .LBF WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM/EXTENDED...SPRINGER AVIATION...POWER
AREA FORECAST DISCUSSION
NWS BUFFALO NY
332 AM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH ACROSS THE REGION TONIGHT SETTING THE STAGE FOR A HOT AND SULTRY MEMORIAL DAY. THE FRONT COULD ALSO HELP TO KICK OFF SOME BENEFICIAL SHOWERS AND THUNDERSTORMS. THE WARMTH WILL EASE ON TUESDAY AS A COLD FRONT WILL MOVE THROUGH THEN TEMPERATURES WILL ACTUALLY DROP TO BELOW NORMAL LEVELS FOR MUCH OF THE REST OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A WARM FRONT LOCATED ACROSS CENTRAL PENNSYLVANIA WILL SLOWLY LIFT NORTHWARD OVERNIGHT. THE 00Z HRRR MODEL ONLY SHOWS SOME CONVECTION MOVING ACROSS NORTHERN NY AFTER 10Z. WHILE THE 00Z NAM SHOWS SOME CONVECTION MOVING ACROSS WESTERN NY NEAR 12Z MONDAY TRIGGERED BY AN UPPER LEVEL DISTURBANCE ROTATING THOUGH THE 500 MB FLOW. CONFIDENCE AT THIS TIME IS TO LOW TO INCLUDE IN GRIDS BUT WILL NEED TO MONITOR IR SATELLITE/RADAR OVERNIGHT. MODELS HAVE NOT HANDLED CONVECTIVE TRENDS VERY WELL OF LATE. WARM FRONT WILL HAVE CLEARED MUCH OF THE AREA MONDAY WITH A HOT AIR MASS MOVING INTO THE REGION. THE 00Z KBUF OBSERVED SOUNDING SHOWED +11C AT 700MB WHICH INDICATED A STRONG MID-LEVEL CAP. FEEL CONVECTIVE ACTIVITY MONDAY WILL BE CONFINED TO ALONG THE FRONT WHERE SOME LOW LEVEL CONVERGENCE COULD POP UP A SHOWER. MEMORIAL DAY TEMPERATURES WILL BE QUITE WARM WITH MOST HIGHS IN THE UPPER 80S TO LOWER 90S. SOME HEAT INDEX VALUES COULD POSSIBLY APPROACH 100F ESPECIALLY THOUGH SOME OF THE SOUTHERN TIER AND GENESEE RIVER VALLEYS. THERE WILL BE SOME RELIEF DUE TO THE SOUTHWEST GRADIENT THAT WILL DEVELOP BY AFTERNOON. RECORD HIGHS AT BUFFALO 86F/1987 AND ROCHESTER 93F/1911 WILL CERTAINLY BE CHALLENGED. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... AN ACTIVE DAY TUESDAY AS ELEVATED SHOWERS AND THUNDERSTORMS TO START THE DAY TRANSITION TO MORE SFC BASED AS THE LOW LEVEL INVERSION IS QUICKLY ERASED BY DAYTIME HEATING. SI`S TO START THE DAY OF -1 TO -3C ALONG WITH A MOIST UNSTABLE AIRMASS WITH OVER AN INCH AND A HALF OF PWATS INDICATES THE POTENTIAL FOR SHOWERS AND THUNDERSTORMS DURING THE MORNING HOURS. BY AFTERNOON DAYTIME INSTABILITY INCREASES WITH 700-850 MB LAPSE RATES OF 8 C/KM. THIS COUPLED WITH FALLING HEIGHTS ALOFT...AN INCREASING UNIDIRECTIONAL WINDS IN THE 0-3 KM LAYER TO 30 KNOTS...AND 1000-2000 J/KG OF CAPE EXPECTED ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS...WITH THE POTENTIAL FOR SOME OF THESE STORMS TO BECOME STRONG TO SEVERE AHEAD OF AN APPROACHING COLD FRONT FROM THE WEST. THE STORM PREDICTION CENTER HAS THE ENTIRE REGION IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS TUESDAY AND TUESDAY EVENING. MODELS ARE IN FAIRLY GOOD AGREEMENT WITH THE COLD FRONT CROSSING THE EASTERN GREAT LAKES TUESDAY NIGHT. AHEAD OF THE COLD FRONT TEMPERATURES TUESDAY WILL STILL RUN ABOVE NORMAL...THOUGH NOT AS HOT AS MONDAY. TEMPERATURES ALOFT AT 850 HPA WILL AVERAGE AROUND +16C...ABOUT 2 TO 4C DEGREES COOLER THAN MONDAY...AND WITH CLOUDS/MOISTURE A LITTLE THICKER TUESDAY EXPECT MORE JUST WIDESPREAD 80S ACROSS THE FA. TUESDAY WILL BECOME BREEZY THROUGH THE DAY AHEAD OF THE COLD FRONT WITH SYNOPTIC WIND GUSTS UP TO 30 MPH...ESPECIALLY DOWNWIND OF THE LAKES. WITH THE CONVECTION TUESDAY AFTERNOON AND EARLY EVENING WE WILL HAVE TO WATCH FOR STRONGER GUSTS WITH A POSSIBLE LINE OF THUNDERSTORMS. TUESDAY EVENING WILL LIKELY FEATURE SHOWERS AND THUNDERSTORMS CONTINUING TO CROSS THE REGION. SFC HIGH PRESSURE REMAINS WELL TO THE WEST...CENTERED OVER THE NORTHERN PLAINS AND WITH THE LOW LEVELS STILL PRETTY MOIST FEEL MUCH OF THE OVERNIGHT TIME PERIOD WILL REMAIN MOSTLY TO COMPLETELY CLOUDY. TEMPERATURES AND DEW POINTS OVERNIGHT WILL LOWER TO MORE COMFORTABLE READINGS TO THE WEST BEHIND THE COLD FRONT PASSAGE...THOUGH WITH THE COLD FRONT LIKELY STILL UPON THE EASTERN FRINGES OF THE CWA BY WEDNESDAY MORNING...THE COOLER AND DRIER AIR WILL ARRIVE THROUGH THE WEDNESDAY MORNING HOURS ACROSS THE NORTHERN FINGER LAKES AND EASTERN LAKE ONTARIO REGION. THE AXIS OF THE UPPER LEVEL TROUGH WILL REMAIN TO OUR WEST THROUGH THE DAY WEDNESDAY. A BREEZY AND MORE COMFORTABLE DAY WILL ENSUE THOUGH A POP UP LIGHT SHOWER CANNOT BE RULED OUT WEDNESDAY AND WEDNESDAY NIGHT WITH THE MID LEVELS STILL REMAINING MOIST. EXPECT AFTERNOON HIGHS WEDNESDAY IN THE 70S...SEASONABLE FOR THE LAST FEW DAYS IN MAY. SURFACE HIGH PRESSURE FROM THE WEST WILL SLOWLY NOSE A LITTLE FARTHER TO THE EAST ON WEDNESDAY NIGHT. WEDNESDAY NIGHT EXPECT LOWS IN THE UPPER 40S TO LOW 50S WITH SOME MID 40S ACROSS THE SOUTHERN TIER. && .LONG TERM /THURSDAY THROUGH SUNDAY/... THURSDAY AND FRIDAY WILL BE THE COOLEST DAYS OF THE WEEK WITH 850MB TEMPS RANGING FROM +3C TO +4C AND AFTERNOON HIGHS IN THE 60S FOLLOWED BY OVERNIGHT LOWS IN THE MID 40S TO LOW 50S. GFS AND ECMWF IN AGREEMENT WITH THE FORMATION OF A CUTOFF LOW ON FRIDAY AND HIGHER LIKELIHOOD OF RAIN ON FRIDAY AND FRIDAY NIGHT WITH TRAILING CHANCE POPS FOR SATURDAY. HIGH PRESSURE RIDGING NORTHWARD FROM THE SOUTHEASTERN STATES BRINGS A RETURN OF WARMER AIR ON SUNDAY WITH HIGHS BACK IN THE LOW TO MID 70S. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... MAINLY VFR CONDITIONS WITH MID LEVEL CIGS EXCEPT FOR KJHW WHICH RECENTLY IS REPORTING SOME MVFR FOG AS A RESULT OF SOME SHOWERS EARLIER TODAY. WINDS AT ALL SITES WILL BE LIGHT AND VARIABLE OVERNIGHT. LATEST 00Z MODELS SHOWING A MIX OF SOLUTIONS WITH REGARD TO OVERNIGHT/MONDAY MORNING CONVECTION MOVING ACROSS THE FORECAST AREA. CONFIDENCE AT THIS TIME IS TO LOW TO INCLUDE IN ANY TAFS BUT WILL NEED TO MONITOR IR SATELLITE/RADAR OVERNIGHT. WARM FRONT WILL LIFT ACROSS THE REGION BY MONDAY MORNING WITH A RIDGE OF WARM AIR ALOFT KEEPING CONVECTION CAPPED WITH VFR. WINDS PICKING UP OUT OF THE SOUTHWEST BY LATE MORNING. OUTLOOK... TUESDAY...AREAS OF MVFR IN SHOWERS/THUNDERSTORMS. WEDNESDAY THROUGH FRIDAY...VFR. && .MARINE... SOUTH WINDS WINDS HAVE PICKED UP THIS EVENING AHEAD OF A WARM FRONT ALONG THE EASTERN END OF LAKE ERIE AND SOUTHWESTERN END OF LAKE ONTARIO. OTHERWISE PRETTY FAIR CONDITIONS ELSEWHERE. SOUTHWEST WINDS WILL INCREASE MONDAY...BUT DUE TO THE HOT AIR MASS ADVECTING INTO THE REGION THE OVER WATER STABILITY WILL LIMIT WIND SPEEDS AND PARTICULARLY WAVE HEIGHTS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...SMITH/TMA NEAR TERM...SMITH/TMA SHORT TERM...THOMAS LONG TERM...WCH AVIATION...WOOD MARINE...SMITH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
202 AM EDT MON MAY 28 2012 .SYNOPSIS... TROPICAL STORM BERYL HAS MOVED ONSHORE NEAR JACKSONVILLE FLORIDA. BERYL...OR THE REMNANTS OF BERYL...MAY BRING SUBSTANTIAL RAINFALL AND GUSTY WINDS TO THE AREA LATE TUESDAY INTO WEDNESDAY AS IT MOVES NORTHEAST OVER THE AREA. AN UNSEASONABLY STRONG UPPER TROUGH AND AN ASSOCIATED COLD FRONT MAY IMPACT THE EASTERN CAROLINAS LATE FRIDAY INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1015 PM SUNDAY...ASIDE FROM SOME SHOWERS BETWEEN GEORGETOWN AND KINGSTREE RADAR SHOWS VERY LITTLE ACTIVITY ACROSS OUR FORECAST AREA CURRENTLY. 18Z SYNOPTIC MODELS PLUS THE LAST FEW HRRR RUNS SHOW SCATTERED SHOWERS DEVELOPING ACROSS THE SOUTH CAROLINA COASTAL WATERS IN THE NEXT FEW HOURS AND PUSHING ONSHORE FROM MYRTLE BEACH SOUTH THROUGH GEORGETOWN BY 2 AM. THIS SEEMS REASONABLE GIVEN THE MOIST UNSTABLE AIRMASS PRESENT COUPLED WITH INCREASING LOW-LEVEL CONVERGENCE IN THE NOCTURNAL ONSHORE FLOW. POPS IN THIS REGION ARE IN THE 30-40 PERCENT RANGE...WITH ONLY 20 PERCENT POPS OFF TO THE NORTH AND WEST. ACROSS INTERIOR SOUTHEASTERN NORTH CAROLINA A COOLER BOUNDARY LAYER SHOULD KEEP SHOWER CHANCES DOWN AROUND 10 PERCENT...TOO LOW FOR MENTION IN THE FORECAST OVERNIGHT. NO OTHER SIGNIFICANT CHANGES HAVE BEEN MADE AT THIS TIME. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... THE CENTER OF TROPICAL STORM BERYL HAS CROSSED THE GULF STREAM AND THE STORM WILL MAKE LANDFALL IN NORTHERN FLORIDA LATER TONIGHT. A TROPICAL AIRMASS CONTINUES TO STREAM ONSHORE IN THE MODERATE EASTERLY WINDS EXTENDING ACROSS ALL OF NORTH AND SOUTH CAROLINA. THIS SHOULD PROVIDE ANOTHER VERY MILD NIGHT WITH LOWS ONLY FALLING INTO THE UPPER 60S INLAND AND LOWER 70S NEAR THE COAST. (THIS IS 5-8 DEGREES ABOVE NORMAL) MODEL SOUNDINGS SHOW HIGH PRECIPITABLE WATER VALUES (1.60 TO 1.75 INCHES) AND NO CAPPING INVERSIONS ALOFT...SO THERE WILL CONTINUE TO BE A POTENTIAL OF ISOLATED SHOWERS MOVING ONSHORE THROUGH THE EVENING HOURS. SHOWER CHANCES SHOULD END INLAND LATER THIS EVENING...BUT CHANCES MAY ACTUALLY INCREASE ACROSS THE COASTAL WATERS AND ALONG THE SOUTH CAROLINA COAST AROUND MIDNIGHT AS LOW-LEVEL WIND CONVERGENCE INCREASES DUE TO DIURNAL COOLING OCCURRING INLAND BUT NOT OVER THE OCEAN. ALL IN ALL...CHANGES FROM THE PRIOR FORECAST ARE MINOR. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...TROPICAL STORM BERYL OR ITS REMNANTS WILL LIKELY BE W OF JACKSONVILLE FL AT THE START OF THE PERIOD. THE OFFICIAL FORECAST ISSUED BY THE NATIONAL HURRICANE CENTER WEAKENS BERYL TO A DEPRESSION BY MON NIGHT. A DEEPENING TROUGH...APPROACHING FROM THE W...IS EXPECTED TO PICK UP BERYL AND TURN IT NORTHWARD TUE AND THEN NE AS IT ACCELERATES UP THE SOUTHEAST COAST. STRONG SHEAR AND LAND INTERACTION WILL TAKE ITS TOLL ON BERYL AND IT IS NOT CLEAR WHAT SHAPE THE SYSTEM WILL BE IN WHEN IT BEGINS ITS ACCELERATION TO THE NE. THE OFFICIAL FORECAST REEMERGES A WEAK SYSTEM OFF THE SOUTH CAROLINA COAST TUE NIGHT AND THEN SHOWS SOME MODEST INTENSIFICATION WITH LOW PRESSURE PASSING WITHIN 40 MILES OF THE MOUTH OF THE CAPE CAPE FEAR RIVER WED MORNING. THE OFFICIAL FORECAST TRACK LIES ON THE EASTERN SIDE OF MODEL CONSENSUS. REGARDLESS OF THE EXACT TRACK AND STRENGTH...CONFIDENCE IS GROWING FOR A SIGNIFICANT RAIN EVENT AS DEEP TROPICAL MOISTURE GETS STEERED NORTHWARD. AT THIS TIME A GOOD 2 TO 3 INCH RAINFALL IS IN THE OFFING WITH A LIKELIHOOD THAT THE HEAVIEST RAIN WILL FALL ACROSS THE EASTERN TWO-THIRDS OF THE FORECAST AREA. CONVECTION ON MON WILL BE LARGELY DIURNALLY DRIVEN AND UNRELATED TO BERYL...WILL KEEP POPS IN SLIGHT CHANCE TO LOW CHANCE RANGE. TIMING IS NOT NAILED DOWN...BUT IN GENERAL...RAIN AND THUNDERSTORMS WILL BE SPREADING NORTHWARD ON TUE WITH THE HEAVIEST RAINFALL RATES EXPECTED LATE TUE INTO WED. THIS MAY POSE SOME HIGH WATER/PONDING ISSUES IN FLOOD PRONE AREAS. WINDS WILL BE ON THE INCREASE TUE NIGHT AND MAY GUST AS HIGH AS 30 TO 35 MPH NEAR/AT THE BEACHES. PREDICTED TIDES WILL NOT BE SIGNIFICANT GIVEN WE WILL BE JUST PAST THE FIRST QUARTER AND SO WE WOULD NEED +1.5 TO 2 FT DEPARTURES...BEFORE COASTAL FLOODING WOULD BE A CONCERN AND WE ARE NOT EXPECTING DEPARTURES OF THAT MAGNITUDE AT THIS TIME. THE HIGHEST OF THE TWO HIGH TIDES WILL OCCUR DURING THE EVENING. THE SURF WILL BE ROUGH AND THE RIP CURRENT RISK ELEVATED TO BE SURE. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 3 PM SUNDAY...BERYL WILL BE IMPACTING THE REGION AT THE START OF THE PERIOD...THOUGH TIMING STILL AN ISSUE. NHC SOLUTION IS BETWEEN THE FASTER ECMWF AND THE SLOWER GFS...THOUGH CLOSER TO THE ECMWF. TIMING WILL DEPEND ON HOW LONG THE SYSTEM STAYS OVER FL/GA. ANOTHER QUESTION IS WHAT SHAPE WILL THE STORM BE AS IT IS PICKED UP BY A BROAD MID LEVEL TROUGH AND LIFTED NORTHEAST. CURRENT FORECAST HAS THE STORM BECOMING A MARGINAL TROPICAL STORM AS IT PASSES THE AREA...BUT IT COULD JUST AS EASILY BE SUB TROPICAL OR EXTRA TROPICAL. HOWEVER THE DIFFERENCE AS FAR AS THE RESULT IS CONCERNED IS NEGLIGIBLE. 20 TO 30 MPH WINDS ALONG THE COAST...SLIGHTLY LESS INLAND...CAN BE EXPECTED...BUT THE BIGGER ISSUE WILL BE RAINFALL. HPC FORECAST IS 3 TO 6 INCHES BUT BASED ON LATEST TRACK MOST OF THIS WILL FALL BEFORE THE START OF THE PERIOD. PRECIP WILL LINGER INTO WED...ESPECIALLY ALONG THE COAST...SO HAVE BUMPED POP TO LIKELY AT THE COAST DECREASING TO CHANCE WELL INLAND. THU IS A TRANSITION DAY WITH FLAT UPPER PATTERN IN THE WAKE OF BERYL TRANSITIONING TO BROAD 5H TROUGHING OVER THE EASTERN US BY FRI MORNING. 5H TROUGH HELPS PUSH COLD FRONT...ASSOCIATED WITH A SYSTEM MOVING THROUGH THE OHIO VALLEY FRI...ACROSS THE AREA FRI NIGHT. DEEP SOUTHERLY FLOW AHEAD OF THE FRONT/TROUGH AND DIVERGENCE ALOFT ENHANCE PRECIP CHANCES FRI...THOUGH ONLY GOING CHANCE FOR NOW. BEST DYNAMICS AND DEEPEST MOISTURE REMAIN NORTHWEST OF AREA. COLD FRONT PUSHES OFF THE COAST LATE SAT MORNING WITH UPPER TROUGH AXIS FOLLOWING SAT NIGHT...DRYING THE AREA OUT FOR THE WEEKEND. CLOUDS AND RAIN WILL KEEP HIGHS A LITTLE BELOW CLIMO ON WED. TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE CLIMO INTO SAT MORNING. MOIST SOUTHERLY FLOW AHEAD OF THE COLD FRONT WILL KEEP LOWS WELL ABOVE CLIMO THU AND FRI NIGHT...NEAR 70 SLIGHTLY COOLER INLAND. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... AS OF 06Z...A VERY MOIST AIRMASS WILL CONTINUE ACROSS THE TERMINALS THIS TAF VALID PERIOD. PRIMARILY BROKEN MVFR LEVEL CLOUDS EXPECTED THROUGH SUNRISE AT ALL TERMINALS...ALTHOUGH THE ONSET OF MVFR CEILINGS AT FLO/LBT MAY HOLD OFF UNTIL 08-09Z. IFR CEILINGS ARE POSSIBLE AS LONG AS CLOUD BASES ARE NEAR 1K FEET...BUT AS OCCURRED THE PREVIOUS COUPLE OF NIGHTS IN THIS SAME AIRMASS EXPECT ANY IFR TO BE SHORT LIVED AND WILL OMIT FROM TAFS ATTM. WITH A DEEP MOIST SOUTHEAST FLOW ISOLATED SHOWERS COULD OCCUR AT ANY TIME...BUT EXPECT THE BEST POTENTIAL BY SUNRISE AT THE COASTAL TERMINALS. AFTER SUNRISE PRIMARILY BROKEN MVFR CEILINGS CAN BE EXPECTED UNTIL AFTERNOON WHEN CEILINGS SHOULD BECOME MOSTLY VFR. SCATTERED SHOWERS EXPECTED TERMINAL-WIDE...WITH THE BEST CHANCE OF SHOWERS AT THE COASTAL TERMINALS DURING THE MORNING AND THE INLAND TERMINALS DURING THE AFTERNOON. SOUTHEASTERLY WINDS EXPECTED THROUGH THE TAF VALID PERIOD...STRONGEST AT THE COASTAL TERMINALS. EXTENDED OUTLOOK...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THROUGH THE EXTENDED PERIOD...WITH THE BEST CHANCE WEDNESDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SUNDAY...WIND AND WAVE OBSERVATIONS SUPPORT THE LATEST FORECAST. NO CHANGES ARE NEEDED WITH THIS LATE EVENING UPDATE. PREVIOUS DISCUSSION FROM 730 PM FOLLOWS... TROPICAL STORM BERYL IS APPROACHING A LANDFALL IN NORTHERN FLORIDA LATER TONIGHT. A BROAD ZONE OF EASTERLY WINDS NORTH OF THE STORM EXTENDS AS FAR NORTH AS THE OUTER BANKS. EAST WINDS WILL VEER SOUTHEASTERLY TONIGHT AS BERYL MOVES FARTHER WEST AND WE ENTER THE NORTHEASTERN PORTION OF THE CYCLONIC VORTEX SURROUNDING THE STORM. WIND SPEEDS NORTH OF CAPE FEAR WILL ONLY AVERAGE 10-15 KT...BUT WILL INCREASE MOVING SOUTH ALONG THE SOUTH CAROLINA COASTLINE...REACHING 20 KNOTS OR SO EAST OF WINYAH BAY AND THE SANTEE RIVER ENTRANCES. SMALL CRAFT ADVISORIES WILL REMAIN POSTED THROUGH THE NIGHT FOR 4-6 FT SEAS...HIGHEST EAST OF FRYING PAN SHOALS DUE TO SWELL IN DEEPER WATER...AND ALSO SOUTH OF MYRTLE BEACH DUE TO STRONGER WIND SPEEDS OCCURRING HERE. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 3 PM SUNDAY...S WINDS THROUGH TUE WILL BACK TO THE SE OR ESE AND INCREASE FROM S TO N TUE NIGHT INTO WED. THE STRONGEST WINDS WILL OCCUR LATE TUE NIGHT INTO WED MORNING AS BERYL...OR ITS REMNANTS...APPROACH FROM THE SW AND THEN MOVE ACROSS OR IN CLOSE PROXIMITY TO THE COASTAL WATERS. THIS MAY BRING TROPICAL STORM FORCE WIND GUSTS TO THE AREA LATE TUE NIGHT AND EARLY ON WED. SEAS OF 4 TO 5 FT MON MORNING WILL SUBSIDE TO 3 TO 4 FT MON AFTERNOON AND MON NIGHT. SEAS WILL NOT BEGIN TO RAMP UP UNTIL TUE NIGHT...BUILDING TO 7 TO 10 FT LATE TUE NIGHT AND WED MORNING. MARINERS SHOULD CONTINUE TO CAREFULLY FOLLOW THE FORECAST THROUGH MID WEEK. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 3 PM SUNDAY...EXITING BERYL WILL KEEP STRONG WINDS AND INCREASED SEAS ACROSS THE WATERS WED. AT THIS POINT IT SEEMS HEADLINES WILL BE NEEDED...THOUGH NOT SURE IF THEY WILL BE TROPICAL STORM OR GALE...THOUGH THE END RESULT WILL BE THE SAME. STRONG BACKING WINDS THROUGH THE DAY WED AS BERYL LIFTS NORTHEAST...THOUGH EXACT TIMING STILL SOMEWHAT IN QUESTION. BRIEF PERIOD OF OFFSHORE FLOW IN THE WAKE OF BERYL WED NIGHT INTO THU BUT WINDS BACK TO SOUTH-SOUTHEAST DURING THU AS COLD FRONT APPROACHES FROM THE WEST. COLD FRONT DOES NOT CROSS THE WATERS UNTIL LATE FRI NIGHT OR SAT MORNING. AHEAD OF THE FRONT THE PINCHED GRADIENT WILL PRODUCE SOUTHWEST FLOW IN THE 15 TO 20 KT RANGE...WITH PROLONGED FETCH POTENTIALLY BUILDING SEAS HIGH ENOUGH TO WARRANT SCA LATE IN THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT THIS AFTERNOON FOR AMZ250- 252-254-256. && $$ AVIATION...MRR
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
234 AM CDT MON MAY 28 2012 .SHORT TERM... THE BROAD UA LOW CONTINUED TO SLOWLY TRANSLATE ENE TOWARDS THE HIGH PLAINS/SOUTHERN SASKATCHEWAN PER 07Z WATER VAPOR IMAGERY. ITS SOUTHERN PERIPHERY SKIRTED ACROSS THE PANHANDLES WHICH HAS RESULTED IN A BRIEFLY STRONG ISOLATED THUNDERSTORM ACROSS THE EASTERN TEXAS PANHANDLE...THAT HAS SINCE SHIFTED EAST ACROSS WESTERN OKLAHOMA. WHAT IS OF CONCERN IS ADDITIONAL CONVECTION DEVELOPING SOUTH AND EAST OF THE SAID STORM IN THE NEXT COUPLE OF HOURS...COINCIDING WITH A NEARBY PACIFIC FRONT THAT HAS INTERSECTED THE CENTRAL PANHANDLES AND THE FAR NORTHWESTERN SOUTH PLAINS EARLY THIS MORNING. THE FRONT IS EXPECTED TO MOVE SOUTH AND EAST ACROSS THE EASTERN PANHANDLES /AOA 08Z/ AND THEN THE NORTHEASTERN SOUTH PLAINS /AOA 10Z/. A LINGERING RETREATING DRYLINE ACROSS THE SOUTHERN PLAINS WILL BE OVERCOME BY THE FRONT AS IS LIKELY WHY THE HRRR AND GFS SOLUTIONS ARE EAGER TO DISPLAY PRECIP ALONG THIS FRONTAL BOUNDARY.... MORESO BETWEEN 06Z AND 12Z. THE FRONTAL PUSH IS NOT IMPRESSIVELY STRONG BUT IS QUITE DRY WITH 07Z METARS DISPLAYING 15 KT WIND SPEEDS AND SINGLE DIGITS DEWPOINTS ACROSS THE WESTERN PANHANDLES. CURRENT THINKING IS THE BEST SYNOPTIC LIFT IS JUST TOO FAR NORTH AND THE GFS AND HRRR SOLUTIONS DISPLAYING PRECIP NEAR THE SOUTHEASTERN TEXAS PANHANDLE AT 06Z AND 07Z RESPECTIVELY WAS OBVIOUSLY OVER DONE. THUS THE DRY NAM AND ECMWF SOLUTIONS MAY HAVE A BETTER HANDLE ON THE SITUATION AND THUS WILL MAINTAIN SILENT POPS THIS MORNING. THIS AFTERNOON HOWEVER IS A DIFFERENT STORY AS THE UA LOW MARCHES EAST ACROSS NORTHERN MINNESOTA/SOUTHERN ONTARIO...AND THE FRONT PUSHES FARTHER SOUTHEAST TO NEAR THE SERN ZONES WHERE IT IS THERE THAT IT STALLS /FROM NEAR PADUCAH SW TO DENVER CITY/. SOUTHERLY FLOW SOUTH OF THE FRONT WILL CONTINUE TO DRAW IN MID LEVEL MOISTURE AS INDICATED BY PROGGED PWATS OF 1.65 INCHES AND PERSISTING DEWPOINTS IN THE 60S THIS EVENING. AS TEMPS WARM INTO THE UPPER 80S TO LOWER TO MID 90S...THE CAPPING INVERSION WILL WEAKEN AND IS EXPECTED TO BREAK AOA 29/00Z. AS FLOW ALOFT EVOLVES TO NEAR ZONAL FLOW...A SUBTLE EMBEDDED DISTURBANCE IS EXPECTED TO MOVE ACROSS THE SOUTHERN PLAINS THIS EVENING...THUS SERVING AS THE SYNOPTIC SPARK POSSIBLY NEEDED TO INITIATE STORMS...ESPECIALLY WITH AN UNIMPRESSIVE FRONTAL BOUNDARY IN PLACE. SFC-BASED CAPE OF 1.5-2.5 KG/KG...INVERTED-V SOUNDING PROFILES...VEERING WIND PROFILES...A LINGERING FRONTAL BOUNDARY AND SUBTLE LARGE SCALE ASCENT SUGGEST THE PROSPECT FOR STORMS TO APPROACH STRONG LEVELS...AND PERHAPS BE CAPABLE OF ORGANIZATION WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. WILL THEREFORE MAINTAIN MENTIONABLE POPS OFF THE CAPROCK WITH EMPHASIS ACROSS THE SERN ZONES...COMMENCING LATE THIS AFTERNOON AND SHIFT BEST PRECIP EASTWARD BY THE END OF THE SHORT TERM PERIOD. && .LONG TERM... ZONAL UPPER LEVEL FLOW TUESDAY WILL AID MIXING OF THE DRYLINE EWD TO NEAR THE ERN BORDER OF THE FCST AREA WITH POTENTIAL FOR ISOLATED TSRA DEVELOPING NEAR IT LATE AFTN AND EARLY EVENING WITH PREVIOUS FCST SLIGHT CHC POPS LOOKING FINE. WILL THEN SEE UPPER LEVEL VEER TO THE NW AS A RIDGE BUILDS OVER THE WRN CONUS. MODELS CONTINUE TO PROG A SHORT WAVE TROUGH MOVING THROUGH THE NWLY FLOW FROM THE CTNL HIGH PLAINS WEDNESDAY TOWARD ARKANSAS BY THURSDAY MORNING. IT STILL APPEARS THAT THIS TROUGH COULD BRING SOME PRECIP INTO THE NERN ZONES WEDNESDAY NIGHT...WITH SOME LOW LEVEL LIFT FROM A COLD FRONT MOVING THROUGH THE FCST AREA IN THE WAKE OF THE UPPER LOW. MODELS CONTINUE TO STRUGGLE WITH THE STRENGTH OF THE COLD FRONT... THE ONSET OF RETURN FLOW...AND THE AMOUNT OF LOW LEVEL MOISTURE AVAILABLE TO ANY STORMS THAT DEVELOP ON THE HIGH TERRAIN TO THE NW OF THE FCST AREA. 00Z RUN HAVE TRENDED TOWARD A COOLER AND DRIER SOLUTION WITH NW FLOW PRECIP NOT IN THE MODELS UNTIL FRIDAY OR SATURDAY NIGHT. WILL RUN NEAR MOS POPS AND TEMPS IN THE THURSDAY THROUGH SUNDAY PERIOD. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 87 55 93 57 89 / 10 10 10 10 10 TULIA 90 59 92 61 89 / 10 10 10 10 10 PLAINVIEW 92 62 95 63 92 / 10 20 10 10 10 LEVELLAND 93 59 97 64 95 / 10 10 10 10 10 LUBBOCK 93 63 98 64 96 / 10 20 10 10 10 DENVER CITY 94 61 96 64 95 / 10 10 10 10 10 BROWNFIELD 94 61 98 64 96 / 20 20 10 10 10 CHILDRESS 94 67 97 68 94 / 20 20 20 20 10 SPUR 95 66 97 67 96 / 20 30 10 10 10 ASPERMONT 97 69 99 70 98 / 20 30 20 20 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 29/07
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1148 PM CDT SUN MAY 27 2012 .DISCUSSION... SEE THE 06Z AVIATION DISCUSSION BELOW. && .AVIATION... CONVECTION TO THE WEST HAS LONG SINCE DISSIPATED...LEAVING SOME MID LEVEL CLOUDS OVERHEAD. THESE CLOUDS WILL MOVE OUT OVERNIGHT WITH PATCHY LOW STRATUS OVERTAKING THE SOUTHERN TERMINALS AFTER 09Z. THE GFS/NAM MOS PRODUCTS CONTINUE TO DEPICT 6-12 HRS OF MVFR CIGS TONIGHT AND EARLY MONDAY BUT THE RAP BUFR SOUNDINGS INDICATE DRIER CONDITIONS IN THE LOWEST 2 KM. GIVEN THE TENDENCY FOR CIGS TO COME IN AROUND 09Z BRIEFLY...DISSIPATE...THEN RETURN AT OR AFTER 12Z...I HAVE SIDED MORE WITH THE RAP. WE DO HAVE A SLIGHTLY WEAKER LOW LEVEL JET TONIGHT WHICH WOULD LIKELY ALLOW STRATUS DECK TO BE A FEW HUNDRED FEET LOWER OWING TO LESS MIXING AND THE ANTICIPATE LACK OF CLOUD COVER LATE COULD FINALLY RESULT IN THE GFS/NAM BEING CORRECT AND EGG ON MY FACE. WE ARE JUST NOW SEEING STRATUS DEVELOP OVER THE HILL COUNTRY WHICH IS ON PAR WITH THE PREVIOUS FEW NIGHTS. FOR NOW...WILL LEAN CONSERVATIVELY. THUNDERSTORM CHANCES RAMP UP TOMORROW AFTERNOON AS A COLD FRONT STALLS TO OUR NORTH AND WEST. THESE STORMS ARE EXPECTED TO DEVELOP FROM NEAR HASKELL TO COLORADO CITY BEFORE 00Z. THE BIG COUNTRY AND NORTHERN CONCHO VALLEY HAVE THE BEST RAIN PROSPECTS GIVEN THE WNW STEERING FLOW BUT THE STRONGER CAP TO THE SOUTH AND EAST SHOULD WEAKEN STORMS AS THEY MOVE AWAY FROM THE BOUNDARY. I DID INCLUDE A PROB30 GROUP FOR TSRA AT KABI AFTER 00Z BUT LEFT THE REMAINING TERMINALS CONVECTION FREE GIVEN THE LOWER CONFIDENCE THAT STORMS WILL MOVE THAT FAR FROM THE BOUNDARY. JOHNSON && .PREV DISCUSSION... /ISSUED 753 PM CDT SUN MAY 27 2012/ UPDATE... SEE UPDATE DISCUSSION BELOW. DISCUSSION... UPDATED GRIDS AND ZONES TO REMOVE POPS FOR TONIGHT. OTHERWISE...CURRENT FORECAST PACKAGE LOOKS GOOD. 21 PREV DISCUSSION... /ISSUED 636 PM CDT SUN MAY 27 2012/ DISCUSSION... SEE THE 00Z AVIATION DISCUSSION BELOW. AVIATION... SCATTERED CU AROUND 5 KFT WILL DISSIPATE THIS EVENING BUT MID LEVEL DEBRIS FROM THE CONVECTION OVER PECOS COUNTY WILL PROVIDE FEW/SCT150 THROUGH THE REMAINDER OF THE EVENING HOURS. THE LOW LEVEL JET IS FORECAST TO BE A BIT WEAKER THAN IN PREVIOUS NIGHTS BUT WE MAY STILL SEE OCCASIONAL GUSTS /MAINLY AFTER 05Z/ AT KSJT AND KABI. A COLD FRONT IS FORECAST TO MOVE SOUTH ACROSS THE PANHANDLE TONIGHT...STALLING FROM A WICHITA FALLS...TO JAYTON...TO SEMINOLE LINE BY 18Z. THUNDERSTORMS ARE EXPECTED TO FORM BY LATE AFTERNOON AND INTO THE EVENING HOURS ALONG THIS FRONT WITH LOCATIONS TO THE SOUTH OF THE BOUNDARY REMAINING FAIRLY WELL CAPPED. A WNW STEERING FLOW WILL LIKELY ADVECT SOME OF THESE STORMS INTO THE BIG COUNTRY AND WESTERN CONCHO VALLEY. HOWEVER...PROBABILITIES REMAIN LOW AT THE FORECAST TERMINALS... SO NO MENTION HAS BEEN MADE. THE OTHER FORECAST PROBLEM WILL BE THE TIMING...DURATION AND EXPANSE OF THE LOW STRATUS. THE MODELS HAVE DONE AN EXTREMELY POOR JOB WITH THE STRATUS OF THE PAST FEW DAYS AND I AM LEANING MORE TOWARDS PERSISTENCE AT THIS POINT. WE WILL HAVE A WEAKER LOW LEVEL JET AND HAVE SLIGHTLY HIGHER DEWPOINTS BUT THE SPORADIC NATURE OF THE CLOUD COVER HAS LEAD TO SIGNIFICANT OVER FORECASTING OF MVFR CONDITIONS. WITH THAT...I HAVE CUT BACK THE DURATION OF THE CIGS AT ALL SITES /EXCEPT AT KABI WHICH WAS ALREADY VFR/ TO MAINLY SEEING MORE PERSISTENT MVFR CIGS BETWEEN 12-16Z. WE WILL PROBABLY SEE SOME BRIEF CIGS DEVELOP BETWEEN 6-12Z BUT WILL HANDLE THESE WITH UPDATES AS TRENDS BECOME MORE APPARENT. JOHNSON PREV DISCUSSION... /ISSUED 359 PM CDT SUN MAY 27 2012/ SHORT TERM... DEEPER LOW LEVEL MOISTURE WITH STRATOCUMULUS WAS MOVING THROUGH WEST CENTRAL TEXAS THIS AFTERNOON...KEEPING TEMPERATURES A FEW DEGREES COOLER THAN YESTERDAY. DRYLINE WAS AGAINST THE SW MOUNTAINS WITH SOME CONVECTION TRYING TO START UP IN HIGHER ELEVATIONS NEAR FORT STOCKTON. WITH THE DRYLINE WELL WEST OF THE REGION THIS AFTERNOON...ONLY THE NW CORNER OF CROCKETT COUNTY HAS POTENTIAL FOR THUNDERSTORM DEVELOPMENT TONIGHT. OTHERWISE GUSTY WINDS ASSOCIATED WITH LEE TROUGH ALONG WITH EXPECTED STRATUS DEVELOPMENT WILL KEEP OVERNIGHT LOWS IN THE LOWER 70S. LATE MONDAY AFTERNOON...THE DRYLINE MOVES EAST INTO THE EASTERN PERMIAN BASIN...AND MAY SEE ISOLATED STORM DEVELOPMENT IN THE LATE AFTERNOON...MAINLY ACROSS THE CONCHO VALLEY AND BIG COUNTRY AS THE STORMS MOVE EAST. BEST CHANCE HOWEVER WILL BE MONDAY NIGHT. WITH GFS SFC CAPES OVER 2500 J/KG AND 0-6 KM SHEARS OF 45 KTS...COULD SEE A FEW SEVERE THUNDERSTORMS...WITH MAIN THREATS OF LARGE HAIL AND DAMAGING WINDS. SPC SEVERE WEATHER OUTLOOK HAS A SLIGHT RISK OF SEVERE THUNDERSTORMS MONDAY...ACROSS THE BIG COUNTRY... CONCHO VALLEY AND HEARTLAND. LONG TERM... STALLED FRONT JUST NORTH OF THE AREA AND THE DRYLINE TO THE WEST WILL CONTINUE TO BE A FOCUS FOR SCATTERED STRONG TO SEVERE THUNDERSTORMS MONDAY EVENING. GFS/NAM GENERATES HIGHEST QPF ALONG THE STALLED FRONT WITH MORE ISOLATED TO WIDELY SCATTERED ACTIVITY ALONG THE DRYLINE. KEPT CHANCE POPS OVER THE BIG COUNTRY WITH SLIGHT CHANCE FARTHER SOUTH AND WEST FOR MONDAY EVENING. MAIN SEVERE THREATS FROM ANY STORMS MONDAY EVENING WILL BE DAMAGING WINDS AND LARGE HAIL. WEAK SHORT WAVE RIDGING WILL PREVAIL ACROSS THE SOUTHERN PLAINS ON TUESDAY...TRANSITIONING TO NORTHWEST FLOW ALOFT TOWARDS THE END OF THE WEEK. THE 850 MB THERMAL RIDGE WILL STRENGTHEN/EXPAND ACROSS WEST TEXAS TUESDAY AND WEDNESDAY...RESULTING IN THE HOTTEST TEMPERATURES FOR THIS WEEK. HIGHS BOTH DAYS WILL CLIMB INTO THE 95 TO 100 DEGREE RANGE ACROSS MUCH OF THE AREA. DRYLINE SHOULD REMAIN CAPPED BOTH DAYS BUT A FEW STORMS MAY DEVELOP ALONG THE STALLED FRONTAL BOUNDARY TO OUR NORTH TUESDAY AFTERNOON. COULD SEE SOME OF THIS ACTIVITY MAKE IT INTO THE NORTHERN BIG COUNTRY SO HELD ONTO SLIGHT POPS ACROSS THIS AREA TUESDAY AFTERNOON/EVENING. A WEAK COLD FRONT IS STILL PROGGED TO MOVE SOUTH ACROSS THE AREA WEDNESDAY NIGHT/EARLY THURSDAY. FRONT LOOKS TO BE DRY...OTHER THAN A SLIGHT CHANCE FOR SHOWERS/THUNDERSTORMS ACROSS THE EASTERN HALF OF THE BIG COUNTRY. THE FRONT WILL BRING COOLER TEMPERATURES TO WEST CENTRAL TEXAS THROUGH THE REST OF THE WEEK. SOUTHERLY FLOW RETURNS THIS WEEKEND WITH TEMPERATURES NEAR NORMAL. GFS INDICATES A WEAK SOUTHERN STREAM CUTOFF UPPER LOW POSSIBLY AFFECTING THE AREA LATER THIS WEEKEND. CONFIDENCE REMAINS LOW WITH THIS SCENARIO SO KEPT THE FORECAST DRY AT THIS TIME. && .PRELIMINARY POINT TEMPS/POPS... ABILENE 70 91 72 97 70 / 10 20 20 10 20 SAN ANGELO 70 93 71 99 71 / 10 20 20 10 10 JUNCTION 71 91 72 95 73 / 0 10 10 10 10 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 25
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
459 AM CDT MON MAY 28 2012 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT 304 AM CDT MON MAY 28 2012 MAIN FORECAST CONCERN IS ON CONVECTION CHANCES TODAY AND ANY POSSIBLE SEVERE WEATHER. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OVER NORTHEAST MONTANA INSIDE UPPER TROUGHING COVERING THE HIGH PLAINS INTO WESTERN MINNESOTA...WHILE RIDGING WAS PRESENT IN THE GREAT LAKES REGION. THE COMBINATION OF HEIGHT FALLS AHEAD OF THE UPPER TROUGH...CONVERGENCE ALONG A SURFACE COLD FRONT...AND A STREAM OF INSTABILITY ALONG THE FRONT HELPED DEVELOP A LARGE EXPANSE OF SHOWERS AND THUNDERSTORMS FROM NORTHEAST MINNESOTA SOUTHWEST INTO EASTERN NEBRASKA LAST EVENING. A LOT OF THIS PRECIPITATION HAS DIMINISHED IN THE PAST FEW HOURS IN RESPONSE TO DIMINISHING INSTABILITY. THE INSTABILITY LOSS IS A COMBINATION OF NOCTURNAL COOLING AND DRY ADVECTION ON SOUTH WINDS...NOTED BY DEWPOINTS IN THE 50S OVER IOWA. NOTE THAT DEWPOINTS IN THE LOW 60S EXIST...BUT THIS IS MOSTLY UNDER THE PRECIPITATION. SURFACE COLD FRONT IS POSITIONED FROM NEAR DULUTH MN...TO ALBERT LEA MN AND SOUTHWEST INTO NORTHEAST KS. PLENTY OF WARM AIR REMAINS AHEAD OF THE FRONT WITH SURFACE TEMPERATURES STILL IN THE 70S OVER MUCH OF THE FORECAST AREA. 850MB TEMPS FROM 00Z SOUNDINGS WERE AROUND 20C. BEHIND THE COLD FRONT...850MB TEMPS DROP OFF TO 13C AT ABR...8C AT BIS AND 2C AT GGW. CLOUDS CLEAR OUT AS WELL DUE TO SUBSIDENCE AND DRY AIR...NOTED ON WATER VAPOR AS WELL WITH A DRY SLOT IN PLACE. TODAY... UPPER TROUGHING OVER THE NORTHERN PLAINS INTO WESTERN MINNESOTA IS PROGGED BY ALL MODELS TO SLIDE EAST...GIVING THE COLD FRONT A PUSH EASTWARD. ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS ALONG/AHEAD OF THE FRONT SHOULD BECOME ISOLATED/SCATTERED IN NATURE AS THEY CROSS THE FORECAST AREA THIS MORNING...DUE TO DIMINISHING INSTABILITY AND FORCING. THE QUESTIONS THEN FOR THE AFTERNOON ARE: 1. HOW MUCH INSTABILITY BUILDS ALONG THE FRONT - PLUME OF LOWER 60S DEWPOINTS OBSERVED ALONG THE FRONT UNDER THE PRECIPITATION IS LIKELY TO STILL EXIST RIGHT INTO THE AFTERNOON. ENVISION THAT PRECIPITATION AND CLOUDS WILL BREAK UP IN THIS AREA OF HIGHER DEWPOINTS...ENOUGH THAT MIXING TO THE 850MB TEMPS OF 14-16C PROGGED AT 18Z WOULD BRING TEMPERATURES UP INTO THE LOW TO MID 80S. THIS RESULTS IN MLCAPE VALUES OF 1000-1500 J/KG ALONG THE FRONT WITH MLCIN DOWN NEAR 0 J/KG. 2. DOES CONVECTIVE INITIATION OCCUR - 0-2KM CONVERGENCE ON THE FRONT IS PRESENT...WEAK...BUT LIKELY ENOUGH GIVEN THE LACK OF MLCIN TO INITIATE CONVECTION. IN FACT...IT IS HARD TO FIND A MODEL THAT DOES NOT INITIATE ON THE FRONT. 3. WHERE IS THE FRONT AT INITIATION - THERE REMAINS TIMING DIFFERENCES. FOR EXAMPLE...THE 28.00Z NAM DOES NOT INITIATE UNTIL THE FRONT IS EAST OF THE AREA (APPROX 21Z)...THOUGH AT 18Z THE ENVIRONMENT IS FAVORABLE FOR INITIATION OVER THE SOUTHEAST END OF THE FORECAST AREA. THE 28.00Z ECMWF/GEM REGIONAL AND HIRES-ARW MODELS ARE SIMILAR TO THE NAM. THE 28.00Z GFS AND SPC WRF-NMM MODELS INITIATE IN THE SOUTHEAST END OF THE FORECAST AREA. KEPT A 50 PERCENT CHANCE IN THE SOUTHEAST END...TAPERING TO 20 PERCENT NEAR LA CROSSE. REGARDING SEVERE WEATHER...0-6KM SHEAR IS 40-50 KT ALONG/AHEAD OF THE FRONT...PLENTY FOR STORM ORGANIZATION. FRONTAL CONVERGENCE AND MLCIN LENDS CONVECTION TO LIKELY FORM A SQUALL LINE...BUT INITIAL CELLS COULD BE SUPERCELLULAR. SOUTHWEST FLOW AND 5-10 KTS OF 0-1KM SHEAR WOULD TEND TO RULE OUT TORNADO THREAT. DRY SLOT COMING IN OVER THE FRONT WILL HELP TO INCREASE DCAPE UP TO 1000-1200 J/KG OR SO...THEREFORE...DEFINITELY HAVE TO WATCH FOR WIND DAMAGE. CANNOT RULE OUT SOME HAIL TOO GIVEN LOWERING WET-BULB ZERO HEIGHTS FROM THE DRY AIR. IN THE WAKE OF THE COLD FRONT...BREEZY WEST WINDS SHOULD DEVELOP WITH CLEARING SKIES. SHOULD BE STILL WARM WEST OF THE FRONT AS THE 850MB TEMP FALL DOES NOT OCCUR UNTIL AFTER 00Z. TONIGHT AND TUESDAY... MODELS TAKE THE UPPER LOW WITHIN THE UPPER TROUGH NORTHEAST INTO NORTHERN ONTARIO ON TUESDAY. ALTHOUGH THE UPPER LOW IS LIFTING AWAY FROM THE AREA...500MB HEIGHTS WILL FALL OVER THE AREA... USHERING IN THE BEGINNING OF A COOL PERIOD. THERE IS ALSO A SHORTWAVE INDICATED TO COME ACROSS NORTHERN WISCONSIN TUESDAY AFTERNOON...ON THE SOUTH SIDE OF THE LOW...WHICH COMBINED WITH DAYTIME HEATING SHOULD PRODUCE SOME ISOLATED SHOWERS ALONG/NORTH OF I-94. GETTING BACK TO TONIGHT...SOMETHING INTERESTING IN MODELS IS A SHORTWAVE AHEAD OF THE UPPER LOW IN CENTRAL MINNESOTA AT 00Z. IT APPEARS SOME SHOWERS AND THUNDERSTORMS SHOULD FIRE UNDER THIS SHORTWAVE. AS THE SHORTWAVE HEADS NORTHEAST...A FEW OF THESE STORMS COULD IMPACT TAYLOR AND CLARK COUNTIES IN THE EVENING...AS SUGGESTED BY THE 28.00Z SPC WRF-NMM...NAM AND GEM REGIONAL MODELS. ADDED A 20-30 PERCENT CHANCE IN THIS AREA. OTHERWISE...THE REST OF THE FORECAST AREA SHOULD BE DRY...WITH BREEZY CONDITIONS LIKELY ON TUESDAY WITH DECENT MIXING AND A RELATIVELY TIGHT PRESSURE GRADIENT IN PLACE. A BLEND OF GUIDANCE SEEMS REASONABLE FOR BOTH LOWS AND HIGHS. TEMPS COULD FALL LATE TUESDAY AS NORTHWEST WINDS DRIVE COOLER 850MB AIR INTO THE AREA (TEMPS DOWN TO 4-6C AT 00Z) TUESDAY NIGHT THROUGH WEDNESDAY NIGHT... UPPER TROUGHING IS FORECAST TO PERSIST OVER THE WESTERN GREAT LAKES THROUGH AT LEAST WEDNESDAY...WHICH ALLOWS CANADIAN HIGH PRESSURE TO BUILD INTO THE FORECAST AREA. AS TO BE EXPECTED...THE 850MB TEMPS CONTINUE TO COOL...DROPPING TO 2-4C BY 18Z WEDNESDAY OR 1.5-2 STANDARD DEVIATIONS BELOW NORMAL. THIS COOLER AIR SHOULD ALLOW TEMPS TO EASILY DROP INTO THE 40S TUESDAY NIGHT...PERHAPS UPPER 30S AT THE TYPICAL COLD SPOTS. IN ADDITION...MIXING AT MOST WOULD ONLY ALLOW FOR HIGHS IN THE LOW 60S ON WEDNESDAY. NOTE... THIS IS STILL FAR FROM THE RECORD COLD HIGH OF 49 AT LA CROSSE SET IN 1897. DRY WEATHER SHOULD DOMINATE THROUGH WEDNESDAY...THOUGH CLOUDS DO LOOK TO BE ON THE INCREASE LATE IN THE DAY. THESE CLOUDS ARE ASSOCIATED WITH A MID LEVEL FRONTOGENESIS ZONE...DOWNSTREAM OF A POTENT SHORTWAVE TROUGH PROGGED TO DROP DOWN INTO THE BLACK HILLS AREA OF SOUTH DAKOTA LATE WEDNESDAY. A LARGE EXPANSE OF SHOWERS COULD BE GOING ON OVER THE DAKOTAS INTO NEBRASKA TOO AHEAD OF THIS SHORTWAVE. SOME OF THESE SHOWERS MAY PUSH INTO THE AREA WEDNESDAY NIGHT. THIS ALL DEPENDS IF THE SHORTWAVE PUSHES EAST TOWARDS MINNESOTA LIKE THE 28.00Z NAM/ECMWF. SHOULD THE 28.00Z GFS/UKMET/CANADIAN VERIFY...WITH THE SHORTWAVE CONTINUING TO DIG MORE SOUTH...WEDNESDAY NIGHT COULD BE DRY. FOR NOW...STUCK WITH A BLEND APPROACH WHICH RESULTS IN 20-40 PERCENT CHANCES SOUTH AND WEST OF I-94. NEITHER SITUATION OF THE SHORTWAVE TRACK PRODUCES ANY CAPE...AND IF ANYTHING THE SCENARIO LOOKS MORE WINTER-LIKE. THEREFORE...PULLED THUNDER MENTION. WEDNESDAY NIGHT ALSO LOOKS COOL...BUT NOT AS COOL AS TUESDAY NIGHT DUE TO MORE CLOUDS. .LONG TERM...THURSDAY THROUGH SUNDAY NIGHT 304 AM CDT MON MAY 28 2012 OVERALL...THE 28.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN AGREEMENT ON THE UPPER LEVEL PATTERN IN THE MEAN. THE MODELS ALL SUGGEST UPPER TROUGHING OVER THE AREA THROUGH AT LEAST SATURDAY... THEN SHIFTING SLOWLY TO THE EAST AS RIDGING BUILDS INTO THE PLAINS. HOWEVER...THERE ARE SOME IMPORTANT DETAILS FOR THURSDAY INTO SATURDAY WHICH CONNECT BACK TO WEDNESDAY NIGHT. THAT POTENT SHORTWAVE WHICH WAS DROPPING INTO SOUTH DAKOTA ON WEDNESDAY...IF IT CONTINUES TO DIG LIKE THE 28.00Z GFS/UKMET/CANADIAN SHOW...WE COULD END UP WITH A REALLY CHILLY PERIOD. THESE MODELS ALL WRAP UP A FAIRLY STRONG SURFACE LOW TO THE SOUTHEAST OF THE AREA. THE CANADIAN IS THE COLDEST OF THEM ALL...WITH A RAINY FRIDAY AND HIGHS ONLY IN THE UPPER 40S. THIS IS THE OUTLIER...BUT DEFINITELY GOES TO SHOW WHAT COULD HAPPEN WITH THAT POTENT SHORTWAVE. ON THE OTHER HAND...THE ECMWF CONTINUES TO INDICATE A MORE PROGRESSIVE IDEA...WHICH OUTSIDE OF A COOL AND POSSIBLY WET THURSDAY...ALLOWS FOR TEMPERATURES TO REBOUND AND CONDITIONS TO DRY OUT. SINCE THE GFS ENSEMBLES ARE SPLIT WITH BOTH IDEAS PLAUSIBLE...HAVE WENT WITH A CONSENSUS BLEND FOR MUCH OF THE LONG TERM FORECAST. LOOKS LIKE FOR THE END OF THE WEEKEND TEMPERATURES WILL WARM BACK TOWARDS NORMAL AS 500MB HEIGHTS RISE. COULD SEE SOME WARM ADVECTION SHOWERS/STORMS TOO SATURDAY NIGHT THROUGH SUNDAY NIGHT...THOUGH LIMITED MOISTURE AVAILABILITY SHOULD LIMIT THE STRENGTH AND COVERAGE OF THE STORMS. && .AVIATION... 1100 PM CDT SUN MAY 27 2012 A COLD FRONT WILL SWEEP ACROSS THE REGION ON MONDAY...LIKELY PASSING KRST BETWEEN 12-15Z AND KLSE 14-17Z. SHOWERS AND STORMS CONTINUE TO FIRE IN AN AXIS OF STRONG LOW LEVEL MOISTURE RETURN/LOW LEVEL JET/INSTABILITY FROM NORTHEAST MN INTO NORTHWEST IA...AND SHOULD APPROACH KRST NEAR 09Z. MESO MODELS SUGGEST THAT THE INSTABILITY WILL HAVE WEAKENED BY THEN...AND SO WILL THE SEVERE/STRONG POTENTIAL OF THE STORMS. THIS ACTIVITY WILL CONTINUE TO DIMINISH AS IT GETS TO KLSE...BUT PROBABLY ENOUGH FOR SHRA AROUND 12Z OR SO. CHECK OF RADAR DOES INDICATE A LINE OF SHRA/TS COULD MOVE ACROSS KRST BEFORE THE BULK OF THE ANTICIPATED PCPN APPROACHES TOWARD 09Z. WILL MAKE AN AMD TO ONGOING TAF. THE NEXT CONCERN IS HOW FAR EAST THE FRONT WILL GET BY THE AFTERNOON. INCREASING INSTABILTY WILL HELP FIRE MORE SHRA/TS ALONG AND AHEAD OF THE BOUNDARY...SOME OF WHICH COULD BECOME STRONG/SEVERE. CONTRASTING VIEW POINTS IN THE MODELS...WITH THE GFS/ARW/SPCWRF SUGGESTING INITIATION COULD BE ON TOP OF KLSE...WHILE THE NAM/GEM/ARXGFS ARE EAST OF KLSE. NOT MUCH CLARITY WITH THE LATEST MODEL RUNS COMPARED TO EARLIER IN THE EVENING. ALL MODELS AGREE THAT KRST SHOULD STAY DRY. WILL KEEP LATE AFTERNOON VCTS POSSIBILITY AT KLSE. && .HYDROLOGY... 459 AM CDT MON MAY 28 2012 RECENT HEAVY RAINS AT THE UPPER END OF THE MISSISSIPPI RIVER BASIN... IN PARTICULAR ACROSS THE MINNEAPOLIS AREA AND ALONG THE MINNESOTA RIVER WHICH DRAINS INTO THE MISSISSIPPI...WILL RESULT IN THE MISSISSIPPI RIVER RISING IN OUR FORECAST AREA. CURRENTLY...ONLY WABASHA IS FORECAST TO EXCEED FLOOD STAGE DURING THE WEEKEND. HOWEVER...MANY OTHER LOCATIONS UP AND DOWN THE MISSISSIPPI RIVER COULD APPROACH FLOOD STAGE. SEE THE LATEST ESF AND RVS STATEMENTS FOR MORE DETAILS ON THE FORECASTS. IF CONFIDENCE INCREASES THAT WABASHA WILL EXCEED FLOOD STAGE...FLOOD WATCHES AND/OR WARNINGS MAY BE ISSUED. LOOKING AHEAD AT PRECIPITATION FOR THIS WEEK...FOR THE MOST PART ONLY A FEW PERIODS OF LIGHT PRECIPITATION ARE EXPECTED...LIKELY TO HAVE LITTLE EFFECT ON THE MISSISSIPPI. HOWEVER...THE 28.00Z CANADIAN MODEL SUGGESTS POTENTIAL FOR MODERATE TO HEAVY RAINFALL COME THURSDAY AND THURSDAY NIGHT. RIGHT NOW THIS MODEL IS CONSIDERED AN OUTLIER. && .ARX WATCHES/WARNINGS/ADVISORIES... 304 AM CDT MON MAY 28 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...RIECK HYDROLOGY...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
444 AM CDT MON MAY 28 2012 UPDATED TO ADD SHORT TERM/MARINE /AVIATION SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE MEDIUM. ACCAS SHOWERS DEVELOPED OVER EASTERN IOWA/FAR WESTERN ILLINOIS IN REGION OF 850 MB CONVERGENCE/MOISTURE TRANSPORT AHEAD OF SHORT WAVE CURRENTLY OVER WESTERN KS ON WATER VAPOR LIFTING NORTHEAST. SOME CAPE BETWEEN 600MB AND 400 MB ON LATEST RAP SOUNDING FOR DBQ...BUT AREA RADARS HAVING A HARD TIME GETTING ANY RETURNS BELOW 10K FT SUPPORTING DRY LAYER BELOW 600 MB ON RAP FORECAST SOUNDINGS. HAVE SLIGHT CHANCES IN THE FAR WEST FIRST THING THIS MORNING...BUT EASTWARD-MOVING OUTFLOW FROM OVERNIGHT CONVECTION IS ENHANCING THE PRECIPITATION AND LATEST HRRR IS PICKING THIS UP...SO WILL NEED TO BE WATCHED FOR AN EARLY UPDATE. CONCERN SHIFTS TO EVOLUTION OF THUNDERSTORMS...AND POSSIBLE SEVERE...LATER TODAY AS BROAD AREA OF SURFACE LOW PRESSURE OVER THE EASTERN DAKOTAS AND MINNESOTA TRIES TO CONSOLIDATE AS OVER LAKE SUPERIOR WITH A TRAILING COLD FRONT MOVING ACROSS STATE THIS AFTERNOON AND EVENING. 925 MB TEMPERATURES SUPPORT MID-UPPER 80S IN THE EAST...WITH LOW 80S WEST AHEAD OF THE FRONT...THOUGH MID CLOUDS WITH 850 MOISTURE ADVECTION COULD TEMPER HIGHS IF THEY THICKEN MORE THAN EXPECTED. OVERALL FORCING IS WEAK...HOWEVER SURFACE-BASED CAPES CLIMB TO 1000-1200 J/KG BY EARLY AFTERNOON WEST...AND LATE AFTERNOON IN THE EAST. UPPER DIVERGENCE IN RIGHT ENTRANCE REGION OF RELATIVELY WEAK/80-85KT/UPPER JET MAX DEVELOPS LATE MORNING/THIS AFTERNOON OVER THE SOUTHEAST HALF OF CWA AND LINGERS THROUGH 06Z....OVERLAYING THE 850 MB CONVERGENCE. MAINLY UNIDIRECTIONAL FLOW WITH SOME SPEED SHEAR AS MID-LEVEL WINDS INCREASE WITH SHORT WAVE PASSAGE...AND WET BULB ZERO HEIGHTS LOWERING TO AROUND 10K FT...SO ANY SEVERE WILL BE MAINLY A WIND/HAIL THREAT WITH LITTLE LOW-LEVEL VEERING...STRAIGHT HODOGRAPHS IN 0-1KM LAYER. HAVE LOW CONFIDENCE SO WILL LEAVE MENTION OF SEVERE OUT OF GRIDS FOR NOW. ENOUGH PRECIPITATION THOUGH TO KEEP LIKELY POPS. WILL TIME SHOWERS AND THUNDERSTORMS ACROSS CWA WITH SURFACE TO 850 MB CONVERGENCE/FRONTOGENETIC FORCING. KEPT CHANCE POPS UNTIL 06Z AS SURFACE TROUGH/FRONT DOES NOT CLEAR SE CWA UNTIL 06Z...WITH ENHANCED SFC TO 850 MB FRONTOGENESIS ALONG LEADING EDGE OF 850 MB COLD AIR. LOWS IN THE 50S BY MORNING EXCEPT FOR LOW 60S IN THE FAR SOUTHEAST. TUESDAY AND WEDNESDAY...FORECAST CONFIDENCE HIGH. BREEZY WEST WINDS EXPECTED ON TUE WITH LINGERING TIGHT PRESSURE GRADIENT AS THE SURFACE LOW MOVES ACROSS LAKE SUPERIOR AND WEAKENS. COLD AIR ADVECTION WILL PERSIST THROUGH THE DAY LEADING TO STEEP LOW LEVEL LAPSE RATES. DIURNAL CUMULUS CLOUDS EXPECTED TO DEVELOP THROUGHOUT ALL BUT FAR SOUTH AND SOUTHEAST FORECAST AREA /CWA/ IN THE AFTERNOON. COOLER MAX TEMPS AROUND 70 TO 72 IN NORTHWEST CWA...BUT 925MB TEMPS AND FEWER CLOUDS SUPPORT UPPER 70S TO AROUND 80 IN FAR SOUTHEAST CWA. THE GFS SPITS OUT SOME LIGHT QPF BOTH TUE AND WED...BUT PREFER DRIER MAJORITY OF MODELS. CANNOT RULE OUT A FEW SPRINKLES IN THE NORTHERN CWA...BUT NOTHING MEASURABLE. 850MB TEMPS DROP TO 0C IN THE MIDDLE OF WI TUE NIGHT. A SHORTWAVE MOVING ACROSS THE STATE COULD LEAD TO A FEW HIGHER CLOUDS IN THE VICINITY. IF WE CLEAR OUT...TEMPS COULD BE IN THE UPPER 30S/LOWER 40S. FOR NOW...TOOK CONSERVATIVE APPROACH WITH LOWS IN THE MID/UPPER 40S. WINDS WILL BE LIGHTER AND OUT OF THE NORTH ON WED...WITH COOLER TEMPS IN THE LOW TO MID 60S...UPPER 50S NEAR THE LAKE AND A LAKE BREEZE. LONG TERM... THURSDAY THROUGH MONDAY...FORECAST CONFIDENCE...MEDIUM. THE GFS AND CANADIAN MODELS SHOW AN UPPER LOW DEVELOPING OVER THE OHIO RIVER VALLEY THROUGH THE WEEKEND WHILE THE ECMWF KEEPS THE UPPER LEVELS PROGRESSIVE. THE INITIAL WARM AIR ADVECTION SHOWERY PRECIP ASSOCIATED WITH THE DEVELOPING CLOSED UPPER LOW IS EXPECTED TO REACH SOUTHERN WI LATER WED NIGHT OR THU...WITH THE ECMWF THE QUICKEST. OFF AND ON LIGHT RAIN SHOWERS WILL BE POSSIBLE THROUGH FRI /ECMWF/...OR EVEN SUNDAY IF YOU BELIEVE THE GFS...WITH THIS SLOW-MOVING LOW PRESSURE SYSTEM. TOOK COMPROMISE OF MODEL SOLUTIONS WHICH LEADS TO SMALL CHANCES FOR PRECIP THROUGH THE ENTIRE EXTENDED FORECAST PERIOD. DO NOT SEE ANY OPPORTUNITY TO GO WITH A DRY PERIOD AT THIS TIME. A WARM AIR ADVECTION PATTERN MOVES INTO SOUTHERN WI FOR THE BEGINNING OF NEXT WEEK WITH A CHANCE FOR THUNDERSTORMS AND TEMPS BACK INTO THE 80S. .AVIATION/12Z TAFS/... 35 TO 40 KNOT 925 MB WINDS KEEPS LOW-LEVEL WIND SHEAR IN TAFS UNTIL MIXING WITH DAYTIME HEATING BRINGS SURFACE WINDS UP AROUND 15Z. VFR CONDITIONS WITH BROKEN MID-HIGH LEVEL CIGS AND GUSTY SOUTHWEST WINDS BETWEEN 25 AND 30 KNOTS AHEAD OF AFTERNOON/EVENING THUNDERSTORMS WITH COLD FRONT PASSAGE. EXPECT ONLY BRIEF REDUCTIONS TO MVFR CIGS/VSBYS WITH THUNDERSTORMS. CAN/T RULE OUT POTENTIAL FOR HAIL OR DAMAGING WINDS WITH SOME OF THE STORMS...BUT THEY WILL BE ISOLATED. THUNDERSTORMS END AT KMKE/KENW BY 06Z...WITH CLEARING SKIES AND VFR VSBYS FOR REMAINDER OF FORECAST PERIOD. .MARINE... EXPECT WINDS TO INCREASE RAPIDLY BY MID-MORNING WITH MIXING UP TO 25 TO 30 KNOT WINDS AROUND 1000 FT. DEEPER MIXING DURING THE DAY ASSURES FREQUENT GUSTS TO 25 KNOTS THROUGH EARLY AFTERNOON...THEN WINDS BEGIN TO SUSIDE WITH SLACKENING PRESSURE GRADIENT WITH APPROACHING SURFACE TROUGH/COLD FRONT. WILL KEEP CURRENT TIMING OF SMALL CRAFT ADVISORY. CHANCE OF THUNDERSTORMS LATE AFTERNOON/EVENING WITH FRONTAL PASSAGE...WITH SOME STORMS POSSIBLY PRODUCING HAIL AND GUSTY WINDS. QUIET WEATHER THROUGH TUESDAY... THOUGH WEST WINDS BEGIN TO INCREASE WITH TIGHTENING GRADIENT BETWEEN HIGH BUILDING INTO THE NORTHERN PLAINS AND DEEPENING LOW PRESSURE OVER WESTERN QUEBEC. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 6 PM CDT THIS EVENING FOR LMZ643>646. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM TUESDAY THROUGH SUNDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
304 AM CDT MON MAY 28 2012 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT 304 AM CDT MON MAY 28 2012 MAIN FORECAST CONCERN IS ON CONVECTION CHANCES TODAY AND ANY POSSIBLE SEVERE WEATHER. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OVER NORTHEAST MONTANA INSIDE UPPER TROUGHING COVERING THE HIGH PLAINS INTO WESTERN MINNESOTA...WHILE RIDGING WAS PRESENT IN THE GREAT LAKES REGION. THE COMBINATION OF HEIGHT FALLS AHEAD OF THE UPPER TROUGH...CONVERGENCE ALONG A SURFACE COLD FRONT...AND A STREAM OF INSTABILITY ALONG THE FRONT HELPED DEVELOP A LARGE EXPANSE OF SHOWERS AND THUNDERSTORMS FROM NORTHEAST MINNESOTA SOUTHWEST INTO EASTERN NEBRASKA LAST EVENING. A LOT OF THIS PRECIPITATION HAS DIMINISHED IN THE PAST FEW HOURS IN RESPONSE TO DIMINISHING INSTABILITY. THE INSTABILITY LOSS IS A COMBINATION OF NOCTURNAL COOLING AND DRY ADVECTION ON SOUTH WINDS...NOTED BY DEWPOINTS IN THE 50S OVER IOWA. NOTE THAT DEWPOINTS IN THE LOW 60S EXIST...BUT THIS IS MOSTLY UNDER THE PRECIPITATION. SURFACE COLD FRONT IS POSITIONED FROM NEAR DULUTH MN...TO ALBERT LEA MN AND SOUTHWEST INTO NORTHEAST KS. PLENTY OF WARM AIR REMAINS AHEAD OF THE FRONT WITH SURFACE TEMPERATURES STILL IN THE 70S OVER MUCH OF THE FORECAST AREA. 850MB TEMPS FROM 00Z SOUNDINGS WERE AROUND 20C. BEHIND THE COLD FRONT...850MB TEMPS DROP OFF TO 13C AT ABR...8C AT BIS AND 2C AT GGW. CLOUDS CLEAR OUT AS WELL DUE TO SUBSIDENCE AND DRY AIR...NOTED ON WATER VAPOR AS WELL WITH A DRY SLOT IN PLACE. TODAY... UPPER TROUGHING OVER THE NORTHERN PLAINS INTO WESTERN MINNESOTA IS PROGGED BY ALL MODELS TO SLIDE EAST...GIVING THE COLD FRONT A PUSH EASTWARD. ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS ALONG/AHEAD OF THE FRONT SHOULD BECOME ISOLATED/SCATTERED IN NATURE AS THEY CROSS THE FORECAST AREA THIS MORNING...DUE TO DIMINISHING INSTABILITY AND FORCING. THE QUESTIONS THEN FOR THE AFTERNOON ARE: 1. HOW MUCH INSTABILITY BUILDS ALONG THE FRONT - PLUME OF LOWER 60S DEWPOINTS OBSERVED ALONG THE FRONT UNDER THE PRECIPITATION IS LIKELY TO STILL EXIST RIGHT INTO THE AFTERNOON. ENVISION THAT PRECIPITATION AND CLOUDS WILL BREAK UP IN THIS AREA OF HIGHER DEWPOINTS...ENOUGH THAT MIXING TO THE 850MB TEMPS OF 14-16C PROGGED AT 18Z WOULD BRING TEMPERATURES UP INTO THE LOW TO MID 80S. THIS RESULTS IN MLCAPE VALUES OF 1000-1500 J/KG ALONG THE FRONT WITH MLCIN DOWN NEAR 0 J/KG. 2. DOES CONVECTIVE INITIATION OCCUR - 0-2KM CONVERGENCE ON THE FRONT IS PRESENT...WEAK...BUT LIKELY ENOUGH GIVEN THE LACK OF MLCIN TO INITIATE CONVECTION. IN FACT...IT IS HARD TO FIND A MODEL THAT DOES NOT INITIATE ON THE FRONT. 3. WHERE IS THE FRONT AT INITIATION - THERE REMAINS TIMING DIFFERENCES. FOR EXAMPLE...THE 28.00Z NAM DOES NOT INITIATE UNTIL THE FRONT IS EAST OF THE AREA (APPROX 21Z)...THOUGH AT 18Z THE ENVIRONMENT IS FAVORABLE FOR INITIATION OVER THE SOUTHEAST END OF THE FORECAST AREA. THE 28.00Z ECMWF/GEM REGIONAL AND HIRES-ARW MODELS ARE SIMILAR TO THE NAM. THE 28.00Z GFS AND SPC WRF-NMM MODELS INITIATE IN THE SOUTHEAST END OF THE FORECAST AREA. KEPT A 50 PERCENT CHANCE IN THE SOUTHEAST END...TAPERING TO 20 PERCENT NEAR LA CROSSE. REGARDING SEVERE WEATHER...0-6KM SHEAR IS 40-50 KT ALONG/AHEAD OF THE FRONT...PLENTY FOR STORM ORGANIZATION. FRONTAL CONVERGENCE AND MLCIN LENDS CONVECTION TO LIKELY FORM A SQUALL LINE...BUT INITIAL CELLS COULD BE SUPERCELLULAR. SOUTHWEST FLOW AND 5-10 KTS OF 0-1KM SHEAR WOULD TEND TO RULE OUT TORNADO THREAT. DRY SLOT COMING IN OVER THE FRONT WILL HELP TO INCREASE DCAPE UP TO 1000-1200 J/KG OR SO...THEREFORE...DEFINITELY HAVE TO WATCH FOR WIND DAMAGE. CANNOT RULE OUT SOME HAIL TOO GIVEN LOWERING WET-BULB ZERO HEIGHTS FROM THE DRY AIR. IN THE WAKE OF THE COLD FRONT...BREEZY WEST WINDS SHOULD DEVELOP WITH CLEARING SKIES. SHOULD BE STILL WARM WEST OF THE FRONT AS THE 850MB TEMP FALL DOES NOT OCCUR UNTIL AFTER 00Z. TONIGHT AND TUESDAY... MODELS TAKE THE UPPER LOW WITHIN THE UPPER TROUGH NORTHEAST INTO NORTHERN ONTARIO ON TUESDAY. ALTHOUGH THE UPPER LOW IS LIFTING AWAY FROM THE AREA...500MB HEIGHTS WILL FALL OVER THE AREA... USHERING IN THE BEGINNING OF A COOL PERIOD. THERE IS ALSO A SHORTWAVE INDICATED TO COME ACROSS NORTHERN WISCONSIN TUESDAY AFTERNOON...ON THE SOUTH SIDE OF THE LOW...WHICH COMBINED WITH DAYTIME HEATING SHOULD PRODUCE SOME ISOLATED SHOWERS ALONG/NORTH OF I-94. GETTING BACK TO TONIGHT...SOMETHING INTERESTING IN MODELS IS A SHORTWAVE AHEAD OF THE UPPER LOW IN CENTRAL MINNESOTA AT 00Z. IT APPEARS SOME SHOWERS AND THUNDERSTORMS SHOULD FIRE UNDER THIS SHORTWAVE. AS THE SHORTWAVE HEADS NORTHEAST...A FEW OF THESE STORMS COULD IMPACT TAYLOR AND CLARK COUNTIES IN THE EVENING...AS SUGGESTED BY THE 28.00Z SPC WRF-NMM...NAM AND GEM REGIONAL MODELS. ADDED A 20-30 PERCENT CHANCE IN THIS AREA. OTHERWISE...THE REST OF THE FORECAST AREA SHOULD BE DRY...WITH BREEZY CONDITIONS LIKELY ON TUESDAY WITH DECENT MIXING AND A RELATIVELY TIGHT PRESSURE GRADIENT IN PLACE. A BLEND OF GUIDANCE SEEMS REASONABLE FOR BOTH LOWS AND HIGHS. TEMPS COULD FALL LATE TUESDAY AS NORTHWEST WINDS DRIVE COOLER 850MB AIR INTO THE AREA (TEMPS DOWN TO 4-6C AT 00Z) TUESDAY NIGHT THROUGH WEDNESDAY NIGHT... UPPER TROUGHING IS FORECAST TO PERSIST OVER THE WESTERN GREAT LAKES THROUGH AT LEAST WEDNESDAY...WHICH ALLOWS CANADIAN HIGH PRESSURE TO BUILD INTO THE FORECAST AREA. AS TO BE EXPECTED...THE 850MB TEMPS CONTINUE TO COOL...DROPPING TO 2-4C BY 18Z WEDNESDAY OR 1.5-2 STANDARD DEVIATIONS BELOW NORMAL. THIS COOLER AIR SHOULD ALLOW TEMPS TO EASILY DROP INTO THE 40S TUESDAY NIGHT...PERHAPS UPPER 30S AT THE TYPICAL COLD SPOTS. IN ADDITION...MIXING AT MOST WOULD ONLY ALLOW FOR HIGHS IN THE LOW 60S ON WEDNESDAY. NOTE... THIS IS STILL FAR FROM THE RECORD COLD HIGH OF 49 AT LA CROSSE SET IN 1897. DRY WEATHER SHOULD DOMINATE THROUGH WEDNESDAY...THOUGH CLOUDS DO LOOK TO BE ON THE INCREASE LATE IN THE DAY. THESE CLOUDS ARE ASSOCIATED WITH A MID LEVEL FRONTOGENESIS ZONE...DOWNSTREAM OF A POTENT SHORTWAVE TROUGH PROGGED TO DROP DOWN INTO THE BLACK HILLS AREA OF SOUTH DAKOTA LATE WEDNESDAY. A LARGE EXPANSE OF SHOWERS COULD BE GOING ON OVER THE DAKOTAS INTO NEBRASKA TOO AHEAD OF THIS SHORTWAVE. SOME OF THESE SHOWERS MAY PUSH INTO THE AREA WEDNESDAY NIGHT. THIS ALL DEPENDS IF THE SHORTWAVE PUSHES EAST TOWARDS MINNESOTA LIKE THE 28.00Z NAM/ECMWF. SHOULD THE 28.00Z GFS/UKMET/CANADIAN VERIFY...WITH THE SHORTWAVE CONTINUING TO DIG MORE SOUTH...WEDNESDAY NIGHT COULD BE DRY. FOR NOW...STUCK WITH A BLEND APPROACH WHICH RESULTS IN 20-40 PERCENT CHANCES SOUTH AND WEST OF I-94. NEITHER SITUATION OF THE SHORTWAVE TRACK PRODUCES ANY CAPE...AND IF ANYTHING THE SCENARIO LOOKS MORE WINTER-LIKE. THEREFORE...PULLED THUNDER MENTION. WEDNESDAY NIGHT ALSO LOOKS COOL...BUT NOT AS COOL AS TUESDAY NIGHT DUE TO MORE CLOUDS. .LONG TERM...THURSDAY THROUGH SUNDAY NIGHT 304 AM CDT MON MAY 28 2012 OVERALL...THE 28.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN AGREEMENT ON THE UPPER LEVEL PATTERN IN THE MEAN. THE MODELS ALL SUGGEST UPPER TROUGHING OVER THE AREA THROUGH AT LEAST SATURDAY... THEN SHIFTING SLOWLY TO THE EAST AS RIDGING BUILDS INTO THE PLAINS. HOWEVER...THERE ARE SOME IMPORTANT DETAILS FOR THURSDAY INTO SATURDAY WHICH CONNECT BACK TO WEDNESDAY NIGHT. THAT POTENT SHORTWAVE WHICH WAS DROPPING INTO SOUTH DAKOTA ON WEDNESDAY...IF IT CONTINUES TO DIG LIKE THE 28.00Z GFS/UKMET/CANADIAN SHOW...WE COULD END UP WITH A REALLY CHILLY PERIOD. THESE MODELS ALL WRAP UP A FAIRLY STRONG SURFACE LOW TO THE SOUTHEAST OF THE AREA. THE CANADIAN IS THE COLDEST OF THEM ALL...WITH A RAINY FRIDAY AND HIGHS ONLY IN THE UPPER 40S. THIS IS THE OUTLIER...BUT DEFINITELY GOES TO SHOW WHAT COULD HAPPEN WITH THAT POTENT SHORTWAVE. ON THE OTHER HAND...THE ECMWF CONTINUES TO INDICATE A MORE PROGRESSIVE IDEA...WHICH OUTSIDE OF A COOL AND POSSIBLY WET THURSDAY...ALLOWS FOR TEMPERATURES TO REBOUND AND CONDITIONS TO DRY OUT. SINCE THE GFS ENSEMBLES ARE SPLIT WITH BOTH IDEAS PLAUSIBLE...HAVE WENT WITH A CONSENSUS BLEND FOR MUCH OF THE LONG TERM FORECAST. LOOKS LIKE FOR THE END OF THE WEEKEND TEMPERATURES WILL WARM BACK TOWARDS NORMAL AS 500MB HEIGHTS RISE. COULD SEE SOME WARM ADVECTION SHOWERS/STORMS TOO SATURDAY NIGHT THROUGH SUNDAY NIGHT...THOUGH LIMITED MOISTURE AVAILABILITY SHOULD LIMIT THE STRENGTH AND COVERAGE OF THE STORMS. && .AVIATION... 1100 PM CDT SUN MAY 27 2012 A COLD FRONT WILL SWEEP ACROSS THE REGION ON MONDAY...LIKELY PASSING KRST BETWEEN 12-15Z AND KLSE 14-17Z. SHOWERS AND STORMS CONTINUE TO FIRE IN AN AXIS OF STRONG LOW LEVEL MOISTURE RETURN/LOW LEVEL JET/INSTABILITY FROM NORTHEAST MN INTO NORTHWEST IA...AND SHOULD APPROACH KRST NEAR 09Z. MESO MODELS SUGGEST THAT THE INSTABILITY WILL HAVE WEAKENED BY THEN...AND SO WILL THE SEVERE/STRONG POTENTIAL OF THE STORMS. THIS ACTIVITY WILL CONTINUE TO DIMINISH AS IT GETS TO KLSE...BUT PROBABLY ENOUGH FOR SHRA AROUND 12Z OR SO. CHECK OF RADAR DOES INDICATE A LINE OF SHRA/TS COULD MOVE ACROSS KRST BEFORE THE BULK OF THE ANTICIPATED PCPN APPROACHES TOWARD 09Z. WILL MAKE AN AMD TO ONGOING TAF. THE NEXT CONCERN IS HOW FAR EAST THE FRONT WILL GET BY THE AFTERNOON. INCREASING INSTABILTY WILL HELP FIRE MORE SHRA/TS ALONG AND AHEAD OF THE BOUNDARY...SOME OF WHICH COULD BECOME STRONG/SEVERE. CONTRASTING VIEW POINTS IN THE MODELS...WITH THE GFS/ARW/SPCWRF SUGGESTING INITIATION COULD BE ON TOP OF KLSE...WHILE THE NAM/GEM/ARXGFS ARE EAST OF KLSE. NOT MUCH CLARITY WITH THE LATEST MODEL RUNS COMPARED TO EARLIER IN THE EVENING. ALL MODELS AGREE THAT KRST SHOULD STAY DRY. WILL KEEP LATE AFTERNOON VCTS POSSIBILITY AT KLSE. && .ARX WATCHES/WARNINGS/ADVISORIES... 304 AM CDT MON MAY 28 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS ALBANY NY
1040 AM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1000 AM EDT...CONTINUE TO FOLLOW AN MCS WORKING TOWARD OUR ADIRONDACKS...BUT WEAKENING. SPC GUIDANCE INDICATED ANY REAL SURFACE INSTABILITY WAS WELL SOUTH AND WEST OF THE CAPITAL REGION. HOWEVER...MID LEVEL LAPSE RATES WERE STEEP...UP TO 7C/KM...AS A EML MOVES OVER THE REGION LATER ON. DEWPOINTS WERE ONLY IN THE 50S FROM ALBANY NORTHWARD...BUT JUMP TO THE 60S FURTHER SOUTH AND EVEN EAST OF THE CAPITAL REGION (BERKSHIRES INCLUDED). UNFORTUNATELY MUCH OF THE MESO SCALE MODELS WERE NOT OF MUCH ASSISTANCE...FAILING TO INITIALIZE THE MCS. THE LATEST HRRR FINALLY HAS LOCKED ONTO IT. THE 12Z NAM HOWEVER...STILL DID NOT DEPICT THE FEATURE! SPC WRF DID APPEAR TO CAPTURE THE MCS BUT LOOKED A LITTLE SLOW AND NORTH WITH ITS PROGRESS. A WARM FRONT WAS PERCHED TO THE SOUTH OF THE CAPITAL REGION AND APPEARS TO BE IN NO HURRY TO LIFT NORTHWARD. IT LOOKS AS IF THE MOST ENERGETIC PORTION OF THE MCS WAS IN THE PROCESS OF LIFTING SOUTHWARD...WITH THE WEAKENING PORTION HEADING INTO OUR AREA WELL NORTH OF THE WARM FRONT. HAVE UPDATED GRIDS TO REFLECT THIS TREND AND WE BELIEVE THIS TREND WILL CONTINUE. HOWEVER...THE COLD POOL ASSOCIATED WITH THIS MCS AS WELL AS OUTFLOW BOUNDARY COULD BECOME FOCUS FOR CONVECTION LATER ON. THE WARM FRONT WILL BE THE SYNOPTIC FOCUS FOR ANY STORMS. SINCE IT LOOKS TO BE A LITTLE SLOWER THAN EARLIER THOUGHT...WE NOW BELIEVE THE GREATEST POTENTIAL FOR CONVECTIVE INITIATION MIGHT ACTUALLY BE THE CATSKILLS...MID HUDSON VALLEY..LITCHFIELD COUNTY INTO THE BERKSHIRES...BUT REALLY ANY AREA IS STILL FAIR GAME FOR DEVELOPMENT BY THIS AFTERNOON AS MIXED LAYER CAPES WILL LIKELY INCREASE TO OVER 1000 J/KG NORTH...AND 2000 J/KG SOUTH LATER THIS AFTERNOON. THE QUESTION WILL BE WHERE EXACTLY CONVECTION WILL DEVELOP. STAY TUNED. DID NOT TINKER WITH THE GRIDS FROM 18Z ON. AFTERNOON HIGHS LOOKED REASONABLE BASED ON WHAT WE HAVE SEEN (UNFORTUNATELY WITHOUT THE ASSISTANCE OF OUR RAOB WHICH IS STILL OTS). LOOKS FOR HIGH TEMPERATURES 85-90 VALLEY LOCATIONS FROM ALBANY SOUTHWARD...80-85 HIGHER TERRAIN. TO THE NORTH ALBANY...HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S VALLEY LOCATIONS...70S HIGHER TERRAIN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... THERE IS A THREAT FOR ISOLATED TO SCATTERED SEVERE THUNDERSTORMS TONIGHT. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MORE WIDESPREAD AND ORGANIZED STORMS ARE EXPECTED TUESDAY INTO TUESDAY EVENING WITH THE THREAT FOR MORE SEVERE THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MUCH OF THE FA IS IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS THROUGH TUESDAY NIGHT. THE WARM FRONT IS EXPECTED TO CONTINUE TO LIFT NORTHEASTWARD FROM ALONG A LINE FROM NEAR OLD FORGE AND BRATTLEBORO AT 00Z TO NORTHEAST VERMONT AND SOUTHEAST MAINE BY EARLY TUESDAY MORNING. MID LEVEL LAPSE RATES CONTINUE TO INCREASE TO 7 TO 8 C/KM. IN ADDITION 0-3 KM HELICITIES REMAIN HIGH BETWEEN 200 AND 400 M2/S2 ACRS NE THIRD OF FA. THUS SUPERCELLS REMAIN POSSIBLE. THE WBZ HEIGHTS START TO DROP TO BTWN 8 AND 10 KFT SO LARGE HAIL ALSO BECOMES MORE OF A THREAT. MORE WIDESPREAD AND ORGANIZED CONVECTION IS EXPECTED TUESDAY AND TUESDAY NIGHT AHEAD OF THE COLD FRONT WHICH IS EXPECTED TO CROSS THE FA LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AND THE UPPER TROUGH. FOR MUCH OF THE PERIOD FROM TUESDAY THROUGH TUESDAY NIGHT THE FA WILL BE IN THE WARM SECTOR WITH A VERY HUMID AIRMASS REMAINING IN PLACE AS DEWPOINTS REMAIN IN THE 60S TO NEAR 70 THROUGH TUESDAY EVENING. WHILE MID LEVEL LAPSES RATES LESSEN TO 6 TO 6.5 C/KM...MLCAPES REMAIN VERY HIGHS WITH UP TO 4000 J/KG POSSIBLE EARLY TUESDAY AFTERNOON AND INCREASING UPPER JET DYNAMICS AS UPPER JET ENDS UP PUTTING FA IN EQUATORWARD ENTRANCE REGION OF A CYCLONICALLY CURVED 100+ KT JET MAX OVER SRN ONTARIO. BOTH DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO BE POSSIBLE ESPECIALLY DURING THE AFTERNOON INTO THE EVENING HOURS ON TUESDAY. EXPECT HIGHS ON TUESDAY IN THE 80S WITH LOWS TUESDAY NIGHT IN THE MID 50S TO MID 60S. HAVE ADDED ENHANCED WORDING FOR THIS ENTIRE PERIOD TO THE ZONE FORECASTS AND GRIDS. THERE WILL STILL BE A CHANCE OF SHOWERS WEDNESDAY MORNING AFTER WHICH DRY WEATHER IS EXPECTED LATE WEDNESDAY INTO WEDNESDAY NIGHT WITH HIGH PRESSURE GRADUALLY BUILDING FROM THE GREAT LAKES INTO THE NORTHEAST. EXPECT HIGHS ON WEDNESDAY IN THE MID 70S TO LOWER 80S WITH LOWS WEDNESDAY NIGHT IN THE MID 40S TO MID 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... FOR MOST FIELDS...POPULATED GRIDDED DATABASE WITH 50/50 BLEND OF 18Z HPC GUIDANCE AND GMOS. THU-THU NT...AN UPPER LEVEL TROUGH AND ATTENDANT MID LEVEL COLD POOL SHOULD PASS ACROSS NORTHERN AREAS THURSDAY. THIS COMBINATION OF SHALLOW INSTABILITY...AND SOME FORCING...ALONG WITH SOME OROGRAPHIC LIFT MAY ALLOW FOR ISOLATED TO SCATTERED SHOWERS ACROSS NORTHERN AND CENTRAL AREAS...WITH THE BEST CHANCE ACROSS HIGHER TERRAIN. AFTER THE TROUGH PASSAGE...A SHORTWAVE RIDGE OF HIGH PRESSURE SHOULD ALLOW FOR CLEARING SKIES LATE THU INTO THU NT. EXPECT SLIGHTLY BELOW SEASONAL TEMPS...WITH MAXES REACHING 70-75 IN VALLEYS...AND 60S ACROSS MOST HIGHER ELEVATIONS...WITH SOME OF THE HIGHEST PEAKS IN THE ADIRONDACKS MOST LIKELY ONLY REACHING THE 50S. FOR OVERNIGHT MINS...EXPECT 45-50 IN VALLEY AREAS...AND UPPER 30S TO MID 40S ACROSS HIGHER ELEVATIONS. FRI-SUN...MOST 00Z/28 DETERMINISTIC MODELS...AS WELL AS THE GEFS...INDICATE A RATHER STRONG LOW PRESSURE SYSTEM POTENTIALLY TRACKING TOWARD THE CENTRAL OR EASTERN GREAT LAKES DURING THIS TIME PERIOD...WITH SOME HINTS OF A SECONDARY SFC WAVE POSSIBLY DEVELOPING E OF THE APPALACHIANS...ALONG OR JUST OFF THE MID ATLANTIC COAST. THIS SHOULD BRING SHOWERS OR A PERIOD OF RAIN TO THE REGION DURING THIS TIME PERIOD...ALTHOUGH MODELS DIFFER ON TIMING. IT APPEARS...BASED ON OVERALL CONSENSUS...THAT BEST CHANCE FOR WIDESPREAD RAIN OR SHOWERS SHOULD BE FRI NT OR SAT. WILL INDICATE CHC POPS BY LATE FRI...AND HIGH CHC FRI NT INTO SAT...TAPERING TO SLIGHT CHC TO LOW CHC BY SUNDAY. DAYTIME MAXES SHOULD BE BELOW NORMAL DURING THIS TIME PERIOD DUE TO CLOUDS AND SOME RAIN...WITH MAXES MAINLY IN THE UPPER 60S TO LOWER 70S IN VALLEYS...AND 60S ACROSS HIGHER ELEVATIONS. OVERNIGHT MINS SHOULD AVERAGE CLOSE TO...OR EVEN A BIT ABOVE SEASONAL LEVELS DUE TO CLOUD COVER...WITH MINS MAINLY IN THE LOWER/MID 50S IN VALLEYS...WITH SOME 40S POSSIBLE ACROSS HIGHER ELEVATIONS. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... A WARM FRONT WILL SLOWLY LIFT NORTHWARD TODAY AND TONIGHT...PROVIDING THE FOCUS FOR A FEW SHOWERS AND THUNDERSTORMS...MAINLY THIS AFTERNOON INTO TONIGHT. STILL DEALING WITH IFR CIGS AT KPOU. SATELLITE PICTURES INDICATE THIS AREA OF STRATUS SHRINKING SO WE ADDED A TEMPO UNTIL 15Z. OTHERWISE...LOOKING AT PRIMARILY VFR CONDITIONS...EXCEPT MVFR IN ANY POSSIBLE THUNDERSTORMS LATER ON. LIGHT/VARIABLE WINDS WILL BECOME SW TO S BY LATE MORNING...AND INCREASE TO 5-10 KT. WINDS WILL BECOME MAINLY S AT LESS THAN 8 KT MONDAY NIGHT. WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND NEAR ANY TSTMS. TUE...VFR/MVFR. SHRA/TSRA LIKELY. IFR POSSIBLE. WED...MVFR/IFR IMPROVING TO VFR. CHC SHRA/TSRA IN THE AM. THU...VFR...NO SIG WX. FRI...VFR/MVFR. CHC SHOWERS ESP IN AFTERNOON. && .FIRE WEATHER... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .HYDROLOGY... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. INCREASING LEVELS OF HUMIDITY ARE EXPECTED UNTIL THE PASSAGE OF THE COLD FRONT LATE TUESDAY NIGHT OR WEDNESDAY MORNING. IN ADDITION PWATS RISE TO BETWEEN 1.50 AND 1.75 INCHES WITH THE POTENTIAL FOR SOME TRAINING CELLS AND SOME BACKBUILDING CELLS. WHILE THE THREAT OF FLOODING IS NOT EXPECTED TO BE WIDESPREAD...ISOLATED TO SCATTERED AREAS MAY HAVE CONDITIONS SIMILAR TO THOSE WHICH OCCURRED SUNDAY EVENING ACROSS SOUTHEAST PORTIONS OF THE FA WHERE SEVERAL INCHES OF RAIN FELL IN A SHORT PERIOD OF TIME...IN THIS CASE IT WAS IN JUST OVER AND HOUR. THEREFORE FLASH FLOODING WOULD BE THE MAJOR CONCERN...BUT DUE TO THE EXPECTED ISOLATED TO SCATTERED NATURE OF OCCURRENCE DO NOT PLAN ON ISSUING A WATCH AT THIS TIME AND WILL HIGHLIGHT IN THE HWO. && .CLIMATE... NEAR RECORD TO RECORD HIGHS FORECAST FOR TODAY RECORD HIGH TEMPERATURES FOR MAY 28TH... ALBANY NY: 91 DEGREES SET BACK IN 1911 RECORDS DATE BACK TO 1820 GLENS FALLS: 88 DEGREES SET BACK IN 1998 (AND PREVIOUS YEARS) RECORDS DATE BACK TO 1944 POUGHKEEPSIE NY: 90 DEGREES SET BACK IN 1977 RECORDS DATE BACK TO 1949 FOR MORE GO TO OUR CLIMATE PAGE AT: WWW.NWS.NOAA.GOV/CLIMATE/LOCAL_DATA.PHP?WFO=ALY && .EQUIPMENT... NO UPPER AIR FLIGHTS FROM ALBANY FOR 00Z/MONDAY AND 12Z/MONDAY. THE SIGNAL PROCESSING SYSTEM FAILED AND PARTS ARE ON EMERGENCY ORDER. WE HOPE TO HAVE A 00Z/TUESDAY UPPER AIR FLIGHT. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/HWJIV/11 NEAR TERM...HWJIV/11 SHORT TERM...11 LONG TERM...KL AVIATION...KL FIRE WEATHER...11 HYDROLOGY...11 CLIMATE...IAA EQUIPMENT...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1026 AM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1000 AM EDT...CONTINUE TO FOLLOW AN MCS WORKING TOWARD OUR ADIRONDACKS...BUT WEAKENING. SPC GUIDANCE INDICATED ANY REAL SURFACE INSTABILITY WAS WELL SOUTH AND WEST OF THE CAPITAL REGION. HOWEVER...MID LEVEL LAPSE RATES WERE STEEP...UP TO 7C/KM...AS A EML MOVES OVER THE REGION LATER ON. DEWPOINTS WERE ONLY IN THE 50S FROM ALBANY NORTHWARD...BUT JUMP TO THE 60S FURTHER SOUTH AND EVEN EAST OF THE CAPITAL REGION (BERKSHIRES INCLUDED). UNFORTUNATELY MUCH OF THE MESO SCALE MODELS WERE NOT OF MUCH ASSISTANCE...FAILING TO INITIALIZE THE MCS. THE LATEST HRRR FINALLY HAS LOCKED ONTO IT. THE 12Z NAM HOWEVER...STILL DID NOT DEPICT THE FEATURE! SPC WRF DID APPEAR TO CAPTURE THE MCS BUT LOOKED A LITTLE SLOW AND NORTH WITH ITS PROGRESS. A WARM FRONT WAS PERCHED TO THE SOUTH OF THE CAPITAL REGION AND APPEARS TO BE IN NO HURRY TO LIFT NORTHWARD. IT LOOKS AS IF THE MOST ENERGETIC PORTION OF THE MCS WAS IN THE PROCESS OF LIFTING SOUTHWARD...WITH THE WEAKENING PORTION HEADING INTO OUR AREA WELL NORTH OF THE WARM FRONT. HAVE UPDATED GRIDS TO REFLECT THIS TREND AND WE BELIEVE THIS TREND WILL CONTINUE. HOWEVER...THE COLD POOL ASSOCIATED WITH THIS MCS AS WELL AS OUTFLOW BOUNDARY COULD BECOME FOCUS FOR CONVECTION LATER ON. THE WARM FRONT WILL BE THE SYNOPTIC FOCUS FOR ANY STORMS. SINCE IT LOOKS TO BE A LITTLE SLOWER THAN EARLIER THOUGHT...WE NOW BELIEVE THE GREATEST POTENTIAL FOR CONVECTIVE INITIATION MIGHT ACTUALLY BE THE CATSKILLS...MID HUDSON VALLEY..LITCHFIELD COUNTY INTO THE BERKSHIRES...BUT REALLY ANY AREA IS STILL FAIR GAME FOR DEVELOPMENT BY THIS AFTERNOON AS MIXED LAYER CAPES WILL LIKELY INCREASE TO OVER 1000 J/KG NORTH...AND 2000 J/KG SOUTH LATER THIS AFTERNOON. THE QUESTION WILL BE WHERE EXACTLY CONVECTION WILL DEVELOP. STAY TUNED. DID NOT TINKER WITH THE GRIDS FROM 18Z ON. AFTERNOON HIGHS LOOKED REASONABLE BASED ON WHAT WE HAVE SEEN (UNFORTUNATELY WITHOUT THE ASSISTANCE OF OUR RAOB WHICH IS STILL OTS). LOOKS FOR HIGH TEMPERATURES 85-90 VALLEY LOCATIONS FROM ALBANY SOUTHWARD...80-85 HIGHER TERRAIN. TO THE NORTH ALBANY...HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S VALLEY LOCATIONS...70S HIGHER TERRAIN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... THERE IS A THREAT FOR ISOLATED TO SCATTERED SEVERE THUNDERSTORMS TONIGHT. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MORE WIDESPREAD AND ORGANIZED STORMS ARE EXPECTED TUESDAY INTO TUESDAY EVENING WITH THE THREAT FOR MORE SEVERE THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MUCH OF THE FA IS IN A SLIGHT RISK FOR SEVERE THUNDERSTORMS THROUGH TUESDAY NIGHT. THE WARM FRONT IS EXPECTED TO CONTINUE TO LIFT NORTHEASTWARD FROM ALONG A LINE FROM NEAR OLD FORGE AND BRATTLEBORO AT 00Z TO NORTHEAST VERMONT AND SOUTHEAST MAINE BY EARLY TUESDAY MORNING. MID LEVEL LAPSE RATES CONTINUE TO INCREASE TO 7 TO 8 C/KM. IN ADDITION 0-3 KM HELICITIES REMAIN HIGH BETWEEN 200 AND 400 M2/S2 ACRS NE THIRD OF FA. THUS SUPERCELLS REMAIN POSSIBLE. THE WBZ HEIGHTS START TO DROP TO BTWN 8 AND 10 KFT SO LARGE HAIL ALSO BECOMES MORE OF A THREAT. MORE WIDESPREAD AND ORGANIZED CONVECTION IS EXPECTED TUESDAY AND TUESDAY NIGHT AHEAD OF THE COLD FRONT WHICH IS EXPECTED TO CROSS THE FA LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AND THE UPPER TROUGH. FOR MUCH OF THE PERIOD FROM TUESDAY THROUGH TUESDAY NIGHT THE FA WILL BE IN THE WARM SECTOR WITH A VERY HUMID AIRMASS REMAINING IN PLACE AS DEWPOINTS REMAIN IN THE 60S TO NEAR 70 THROUGH TUESDAY EVENING. WHILE MID LEVEL LAPSES RATES LESSEN TO 6 TO 6.5 C/KM...MLCAPES REMAIN VERY HIGHS WITH UP TO 4000 J/KG POSSIBLE EARLY TUESDAY AFTERNOON AND INCREASING UPPER JET DYNAMICS AS UPPER JET ENDS UP PUTTING FA IN EQUATORWARD ENTRANCE REGION OF A CYCLONICALLY CURVED 100+ KT JET MAX OVER SRN ONTARIO. BOTH DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO BE POSSIBLE ESPECIALLY DURING THE AFTERNOON INTO THE EVENING HOURS ON TUESDAY. EXPECT HIGHS ON TUESDAY IN THE 80S WITH LOWS TUESDAY NIGHT IN THE MID 50S TO MID 60S. HAVE ADDED ENHANCED WORDING FOR THIS ENTIRE PERIOD TO THE ZONE FORECASTS AND GRIDS. THERE WILL STILL BE A CHANCE OF SHOWERS WEDNESDAY MORNING AFTER WHICH DRY WEATHER IS EXPECTED LATE WEDNESDAY INTO WEDNESDAY NIGHT WITH HIGH PRESSURE GRADUALLY BUILDING FROM THE GREAT LAKES INTO THE NORTHEAST. EXPECT HIGHS ON WEDNESDAY IN THE MID 70S TO LOWER 80S WITH LOWS WEDNESDAY NIGHT IN THE MID 40S TO MID 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... FOR MOST FIELDS...POPULATED GRIDDED DATABASE WITH 50/50 BLEND OF 18Z HPC GUIDANCE AND GMOS. THU-THU NT...AN UPPER LEVEL TROUGH AND ATTENDANT MID LEVEL COLD POOL SHOULD PASS ACROSS NORTHERN AREAS THURSDAY. THIS COMBINATION OF SHALLOW INSTABILITY...AND SOME FORCING...ALONG WITH SOME OROGRAPHIC LIFT MAY ALLOW FOR ISOLATED TO SCATTERED SHOWERS ACROSS NORTHERN AND CENTRAL AREAS...WITH THE BEST CHANCE ACROSS HIGHER TERRAIN. AFTER THE TROUGH PASSAGE...A SHORTWAVE RIDGE OF HIGH PRESSURE SHOULD ALLOW FOR CLEARING SKIES LATE THU INTO THU NT. EXPECT SLIGHTLY BELOW SEASONAL TEMPS...WITH MAXES REACHING 70-75 IN VALLEYS...AND 60S ACROSS MOST HIGHER ELEVATIONS...WITH SOME OF THE HIGHEST PEAKS IN THE ADIRONDACKS MOST LIKELY ONLY REACHING THE 50S. FOR OVERNIGHT MINS...EXPECT 45-50 IN VALLEY AREAS...AND UPPER 30S TO MID 40S ACROSS HIGHER ELEVATIONS. FRI-SUN...MOST 00Z/28 DETERMINISTIC MODELS...AS WELL AS THE GEFS...INDICATE A RATHER STRONG LOW PRESSURE SYSTEM POTENTIALLY TRACKING TOWARD THE CENTRAL OR EASTERN GREAT LAKES DURING THIS TIME PERIOD...WITH SOME HINTS OF A SECONDARY SFC WAVE POSSIBLY DEVELOPING E OF THE APPALACHIANS...ALONG OR JUST OFF THE MID ATLANTIC COAST. THIS SHOULD BRING SHOWERS OR A PERIOD OF RAIN TO THE REGION DURING THIS TIME PERIOD...ALTHOUGH MODELS DIFFER ON TIMING. IT APPEARS...BASED ON OVERALL CONSENSUS...THAT BEST CHANCE FOR WIDESPREAD RAIN OR SHOWERS SHOULD BE FRI NT OR SAT. WILL INDICATE CHC POPS BY LATE FRI...AND HIGH CHC FRI NT INTO SAT...TAPERING TO SLIGHT CHC TO LOW CHC BY SUNDAY. DAYTIME MAXES SHOULD BE BELOW NORMAL DURING THIS TIME PERIOD DUE TO CLOUDS AND SOME RAIN...WITH MAXES MAINLY IN THE UPPER 60S TO LOWER 70S IN VALLEYS...AND 60S ACROSS HIGHER ELEVATIONS. OVERNIGHT MINS SHOULD AVERAGE CLOSE TO...OR EVEN A BIT ABOVE SEASONAL LEVELS DUE TO CLOUD COVER...WITH MINS MAINLY IN THE LOWER/MID 50S IN VALLEYS...WITH SOME 40S POSSIBLE ACROSS HIGHER ELEVATIONS. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... A WARM FRONT WILL SLOWLY LIFT NORTHWARD TODAY AND TONIGHT...PROVIDING THE FOCUS FOR A FEW SHOWERS AND THUNDERSTORMS...MAINLY THIS AFTERNOON INTO TONIGHT. STILL DEALING WITH IFR CIGS AT KPOU. SATELLITE PICTURES INDICATE THIS AREA OF STRATUS SHRINKING SO WE ADDED A TEMPO UNTIL 15Z. OTHERWISE...LOOKING AT PRIMARILY VFR CONDITIONS...EXCEPT MVFR IN ANY POSSIBLE THUNDERSTORMS LATER ON. LIGHT/VARIABLE WINDS WILL BECOME SW TO S BY LATE MORNING...AND INCREASE TO 5-10 KT. WINDS WILL BECOME MAINLY S AT LESS THAN 8 KT MONDAY NIGHT. WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND NEAR ANY TSTMS. TUE...VFR/MVFR. SHRA/TSRA LIKELY. IFR POSSIBLE. WED...MVFR/IFR IMPROVING TO VFR. CHC SHRA/TSRA IN THE AM. THU...VFR...NO SIG WX. FRI...VFR/MVFR. CHC SHOWERS ESP IN AFTERNOON. && .FIRE WEATHER... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .HYDROLOGY... A WARM FRONT WILL LIFT NORTHWARD THROUGH TODAY...PROVIDING A FOCUS FOR ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. INCREASING LEVELS OF HUMIDITY ARE EXPECTED UNTIL THE PASSAGE OF THE COLD FRONT LATE TUESDAY NIGHT OR WEDNESDAY MORNING. IN ADDITION PWATS RISE TO BETWEEN 1.50 AND 1.75 INCHES WITH THE POTENTIAL FOR SOME TRAINING CELLS AND SOME BACKBUILDING CELLS. WHILE THE THREAT OF FLOODING IS NOT EXPECTED TO BE WIDESPREAD...ISOLATED TO SCATTERED AREAS MAY HAVE CONDITIONS SIMILAR TO THOSE WHICH OCCURRED SUNDAY EVENING ACROSS SOUTHEAST PORTIONS OF THE FA WHERE SEVERAL INCHES OF RAIN FELL IN A SHORT PERIOD OF TIME...IN THIS CASE IT WAS IN JUST OVER AND HOUR. THEREFORE FLASH FLOODING WOULD BE THE MAJOR CONCERN...BUT DUE TO THE EXPECTED ISOLATED TO SCATTERED NATURE OF OCCURRENCE DO NOT PLAN ON ISSUING A WATCH AT THIS TIME AND WILL HIGHLIGHT IN THE HWO. && .EQUIPMENT... NO UPPER AIR FLIGHTS FROM ALBANY FOR 00Z/MONDAY AND 12Z/MONDAY. THE SIGNAL PROCESSING SYSTEM FAILED AND PARTS ARE ON EMERGENCY ORDER. WE HOPE TO HAVE A 00Z/TUESDAY UPPER AIR FLIGHT. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/HWJIV/11 NEAR TERM...HWJIV/11 SHORT TERM...11 LONG TERM...KL AVIATION...HWJIV/KL FIRE WEATHER...11 HYDROLOGY...11 EQUIPMENT...IAA
AREA FORECAST DISCUSSION
NWS MIAMI FL
913 AM EDT MON MAY 28 2012 .UPDATE... ONLY SLIGHT MODIFICATIONS WERE MADE THIS MORNING BASED ON THE MORNING ANALYSIS AND THE LATEST MODEL GUIDANCE. THE MORNING VAPOR LOOP SHOWED A DRY SLOT ACROSS SOUTH FLORIDA WITH MOST OF THE DEEP LAYER MOISTURE REMAINING OVER N/CENTRAL FL ASSOCIATED WITH BERYL. THIS LINES UP WELL WITH THE MORNING UPPER AIR SOUNDING AT MFL...WHICH INDICATED PWAT VALUES DOWN FROM 1.68 LAST NIGHT TO 1.27 INCHES THIS MORNING. PRIMARY FLOW THROUGH THE COLUMN WILL REMAIN OUT OF THE SSW TODAY...WHICH FAVORS AFTERNOON CONVECTION SETTING UP OVER THE NORTH AND EASTERN HALF OF THE PENINSULA...OR ANYWHERE FROM INLAND MIAMI-DADE TO PALM BEACH COUNTIES. THE LATEST WRF AND HRRR MODEL REFLECTIVITY OUTPUT LINES UP WELL THIS GENERAL PATTERN AND INDICATES MOST OF THE AFTERNOON CONVECTION INITIATING AROUND AND AFTER 18Z AND CONTINUING THROUGH THE EARLY EVENING PERIOD BEFORE TRENDING DOWN THROUGH THE MID/LATE EVENING HOURS AS TYPICALLY OBSERVED. THE PRIMARY THREATS WITH THIS ACTIVITY TODAY WILL BE FREQUENT LIGHTNING...GUSTY WINDS (WINDEX IN THE 40 TO 60 MPH RANGE)...SMALL HAIL AND PERIODS WITH HEAVY RAINFALL. AS A RESULT...WE HAVE SLIGHTLY TWEAKED THE RAINFALL PROBABILITIES ACROSS THE AREA THROUGH THIS TIME TODAY. OTHERWISE...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK WITH NO OTHER CHANGES NECESSARY. 85/AG && .PREV DISCUSSION... /ISSUED 701 AM EDT MON MAY 28 2012/ AVIATION... VFR CONDITIONS WITH LIGHT WINDS AT 5 KNOTS OR LESS SHOULD PREVAIL THROUGH THE MID MORNING HOURS TODAY. MEAN WEST-SOUTHWEST WIND FLOW SHOULD INTERACT WITH DEVELOPING SEA BREEZES ALONG THE EAST COAST TO INDUCE THE DEVELOPMENT OF TSTMS BY EARLY AFTERNOON. ONCE AGAIN, A SOUTHWESTERLY FLOW ALOFT SHOULD STEER ANY STORM TOWARD THE EAST COAST CLOSE TO THE ERN TERMINALS. WL EXPECT THE SOUTHWEST FLOW TO KEEP KAPF FREE OF ANY STORM BY PUSHING ANY DEVELOPMENT FURTHER INLAND. AVIATION...BNB/RGH PREV DISCUSSION... /ISSUED 358 AM EDT MON MAY 28 2012/ DISCUSSION... AS TROPICAL STORM BERYL CONTINUES ON ITS WESTWARD TRACK TODAY AND THEN FORECAST TO MOVE NORTHEAST EARLY TUESDAY...WINDS ACROSS THE REGION WILL BE SOUTHWESTERLY TO SOUTHERLY THROUGH AT MID-WEEK. UNDER THIS REGIME...THE FORECAST FOR THE WORK WEEK IS FOR SHOWERS AND THUNDERSTORMS EXPECTED ACROSS THE SOUTH FLORIDA PENINSULA MAINLY DURING THE LATER PART OF THE AFTERNOON AND INTO THE EVENING HOURS. THE SUITE OF MODEL GUIDANCE CONSISTENTLY INDICATED LOW LEVEL SOUTHWESTERLY FLOW THROUGH AT LEAST MID WEEK WHICH WILL FAVOR AFTERNOON CONVECTION ACROSS THE EASTERN HALF OF THE PENINSULA. THE LATEST GUIDANCE ALSO INDICATED AN UPPER LEVEL TROUGH PERSISTING ACROSS THE EASTERN GULF THROUGH AT LEAST MID WEEK WHICH WILL HELP TO ENHANCE AFTERNOON CONVECTION. IN ADDITION THE SOUTHERLY FLOW WILL HELP TO MAINTAIN WARMER TEMPERATURES ACROSS THE REGION WITH THE ATLANTIC COAST METRO AREAS POSSIBLY REACHING THE UPPER 80S EACH DAY BEFORE THE CONVECTION STARTS WITH NEAR 90 TEMPERATURES POSSIBLE IN THE WESTERN METRO AREAS. FOR TODAY NEED TO EMPHASIZE THE CHANCE OF A FEW STRONG THUNDERSTORMS...AGAIN MAINLY EXPECTED ACROSS THE EASTERN HALF OF THE PENINSULA DURING THE LATE AFTERNOON AND EVEN HOURS. ACCORDING TO THE LATEST GUIDANCE THE STRONGER UPPER LEVEL WINDS ARE CURRENTLY ACROSS THE FLORIDA STRAITS AND ARE FORECAST TO LIFT NORTHWARD AS THE DAY PROGRESSES...WITH MAINLY THE SOUTHERN PORTIONS OF THE PENINSULA AFFECTED. BUT THIS WILL HELP TO MAINTAIN UPPER LEVEL SPEED DIVERGENCE AND HELP TO MAINTAIN A FEW STRONG THUNDERSTORMS. IN ADDITION RECENT WATER VAPOR IMAGERY INDICATES MID TO UPPER LEVEL DRIER AIR ACROSS SOUTH FLORIDA WHICH IS ON THE SOUTHERN PERIPHERY OF TROPICAL STORM BERYL. THIS COULD ADD TO THE POTENTIAL FOR HAIL WITH THE STRONGEST THUNDERSTORMS TODAY. MARINE... AS TROPICAL STORM BERYL CONTINUES ON ITS WESTWARD TRACK TODAY AND THEN FORECAST TO MOVE NORTHEAST EARLY TUESDAY...ITS PRESENCE ACROSS THE SOUTHEAST U.S. WILL HELP TO MAINTAIN A WEAKENED PRESSURE GRADIENT ACROSS THE SOUTH FLORIDA GULF AND ATLANTIC WATERS THROUGH AT LEAST MID-WEEK WITH A MORE SOUTHERLY FLOW ACROSS THE REGION. WINDS ACROSS THE LOCAL ATLANTIC WATERS WILL SLOWLY SUBSIDE TODAY INTO TUESDAY WITH GULF STREAM SEAS SLOWLY SUBSIDING. WINDS AND SEAS ARE FORECAST TO REMAIN WELL BELOW ADVISORY LEVELS ACROSS THE REGIONAL WATERS THROUGH AT LEAST THURSDAY. FIRE WEATHER... NO FIRE WEATHER CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 87 74 88 74 / 50 30 40 30 FORT LAUDERDALE 85 76 89 76 / 20 30 40 30 MIAMI 87 76 89 75 / 20 30 40 30 NAPLES 88 74 88 73 / 20 30 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...85/AG AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
1011 AM EDT MON MAY 28 2012 .UPDATE...NO SIGNIFICANT CHANGES PLANNED FOR THIS UPDATE AS POP GRIDS LOOK IN GOOD SHAPE WITH SHARP GRADIENT GRADUALLY EXPANDING AS RAIN BANDS MOVE FURTHER AWAY FROM CENTER. FIRST SUCH BAND MOVING INTO THE SOUTHEAST GEORGIA COAST AT THIS HOUR AND WITH SOME HEATING...ALTHOUGH LIMITED BY ABUNDANT CLOUD COVER...SHOULD SEE INCREASE IN COVERAGE FOR SOUTHEAST CORNER THROUGH EARLY AFTERNOON. BIGGER QUESTIONS BECOMES HOW FAR NORTH SHOWERS MAKE IT THIS AFTERNOON. RAP FOR THE NEXT 6 HOURS NOT SHOWING MUCH SURFACE BASED CAPE INCREASE AND SHOULD ONLY SEE VALUES APPROACH 1000 J/KG OVER A SMALL SECTION OF CENTRAL GEORGIA. HRRR IS REALLY THE ONLY MODEL BULLISH ABOUT BRING RAINBAND SHOWERS INTO NORTH GEORGIA AND FEEL CURRENTLY ADVERTISED LOW END CHANCE GRIDS HANDLE THIS WELL. WILL UPDATE WIND FIELDS BASED ON NEW GUIDANCE...OTHERWISE WILL HOLD WITH WHAT WE HAVE GRID WISE. && .PREV DISCUSSION... /ISSUED 754 AM EDT MON MAY 28 2012/ PREV DISCUSSION... /ISSUED 353 AM EDT MON MAY 28 2012/ .GUSTY WINDS OVER AREAS SOUTH OF I-85 AND PERIODS OF HEAVY RAIN EXPECTED IN FAR SOUTHERN TIER OF COUNTIES FROM TROPICAL STORM BERYL TODAY... SHORT TERM /TODAY THROUGH TUESDAY/... PRIMARY CONCERN IN THE SHORT TERM PERIOD IS IMPACT OF TS BERYL WHICH MADE LANDFALL NEAR JACKSONVILLE FL AROUND MIDNIGHT. OUTER BAND OF SHOWERS MOVED THROUGH SOME SE COUNTIES WITH SOME GUSTS OF 20 TO 25KTS BUT THIS BAND HAS DISSIPATED WITH GUSTS BACK DOWN TO 20KTS OR LESS. GUSTY WINDS WILL LIKELY BE THE MAIN IMPACT OF BERYL ACROSS AREAS SOUTH OF I-85 WHERE WINDS COULD GUST TO AROUND 25 MPH .APPROACHING 35 MPH SOUTH AND EAST OF MACON...JUST BELOW WIND ADVISORY CRITERIA. LATEST HPC QPF CONTINUES DOWNWARD TREND OF AMOUNTS OF SOUTHERN CWA TODAY AND TONIGHT. 00Z ECMWF AND 00Z NAM ALSO KEEP BULK OF PRECIP OVER SOUTHERN COUNTIES TODAY THOUGH 00Z GFS AND 21Z SREF DO INDICATE SOME POTENTIAL FOR SCT SHRA/TSRA THIS AFTERNOON. BY TONIGHT...CONVECTION WILL VERY LIKELY BE CONTAINED NEAR THE CENTER OF THE REMNANTS OF BERYL WHICH WILL BE SOMEWHERE OVER FAR S GA AT THAT TIME. TUESDAY...REMNANTS OF BERYL WILL INTERACT WITH AN APPROACHING FRONT SWEEPING IN WITH THE HELP OF FAIRLY STRONG WESTERLIES OVER THE OH VALLEY AND MIDWEST. HAVE KEPT POPS IN CHC TO LKLY CATEGORY BUT COULD BE A LITTLE MORE WIDESPREAD AS THE FCST PROGRESSES. TWEAKED TEMPS BASED ON RECENT 30 DAY BIASES AND EXPECTATIONS FOR LOWER DIURNAL RANGES DUE TO TS BERYL. MIN TEMPS HAVE BEEN MUCH WARMER THAN GUIDANCE RECENTLY /CURRENT TEMPS STILL IN LOW TO MID 70S...ABOUT 4 TO 8 DEGS HIGHER THAN 12Z MAV/MET GUIDANCE FCST FOR THIS TIME/. THIS TREND SHOULD CONTINUE UNTIL DRIER AIRMASS MOVES THROUGH. SNELSON LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE REMNANTS OF TROPICAL STORM BERYL IS FORECAST TO MOVE TO THE NORTHEAST AND EXIT THE STATE ALONG THE SC COAST TUESDAY NIGHT OR EARLY WEDNESDAY MORNING. THE GFS AND ECMWF HAVE A FAIRLY GOOD HANDLE ON THIS MOVEMENT...WITH A DRIER NORTHERLY WIND FLOW IN ITS WAKE ON WEDNESDAY. WILL SHOW A SLIGHT CHANCE OF THUNDER ON WEDNESDAY AS BOTH MODELS SHOW AN ACTIVE WESTERLY FLOW ALOFT AND A WEAK SURFACE TROUGH STILL ACROSS THE STATE. RAIN CHANCES SIGNIFICANTLY INCREASE FOR THURSDAY AND FRIDAY AS GFS AND ECMWF AGREE ON AN UPPER LOW AND ASSOCIATED FRONTAL BOUNDARY KICKING EAST OF THE PLAINS ON THURSDAY AND DRAGGING A COLD FRONT ACROSS THE FORECAST AREA FRIDAY NIGHT. EXPECT THE GREATER THUNDERSTORM THREAT TO BE ON FRIDAY AHEAD OF THE APPROACHING FRONT...WITH 2000-2500 CAPE...40KT LOW LEVEL JET AND MODERATE DIFFLUENT FLOW ALOFT. TOTAL RAINFALL AMOUNTS FOR THURSDAY AND FRIDAY WILL LIKELY BE LESS THAN AN INCH. MODELS SHOW CLEARING CONDITIONS EARLY SATURDAY...WITH DRY HIGH PRESSURE SETTLING IN FOR THE WEEKEND. 39 FIRE WEATHER... WINDS ACROSS AREAS SOUTH OF I-85 WILL APPROACH FIRE DANGER CRITERIA TODAY. AS MENTIONED PREVIOUSLY...OCCASIONAL SHOWERS SHOULD MITIGATE ANY DANGEROUS FIRE WEATHER CONDITIONS. WILL NEED TO MONITOR THIS THROUGH THE DAY IN CASE PRECIP BECOMES MORE CONCENTRATED AROUND TS BERYL LEAVING THINGS HIGH AND DRY IN MIDDLE GA. FUELS CONTINUE TO REMAIN VERY LOW. HYDROLOGY... MAX RAINFALL IN SE PARTS OF CWA NOW FCST TO REMAIN AT OR BELOW 2 INCHES. WITH DRY ANTECEDENT CONDITIONS AND CORRESPONDING HIGH FFG VALUES OF 4 TO 5 INCHES IN 3 HOURS...WILL NOT BE ISSUING ANY TYPE OF FLOOD WATCH. PRECIP WITH OUTER BAND THAT MOVED THROUGH EARLIER THIS MORNING ONLY PRODUCED A TENTH TO A QUARTER INCH SO FAR. AVIATION... 12Z UPDATE... SAT IMAGERY MORE CLEARLY SHOWING STRATUS THIS MORNING...SEVERAL HOLES APPEARANT ESP OVER EAST CENTRAL GA. STRATUS WITH 1500FT CIGS SHOULD APPROACH ATL METRO AIRPORTS BETWEEN 12 AND 13Z BUT WILL LIKELY HAVE PERIODS OF SCT COVERAGE UNTIL AFTERNOON WHEN SHOULD SEE BKN CU DECK AROUND 4000FT. TSRA ASSOCIATED WITH PERIPHERY OF BERYL SHOULD MOSTLY AFFECT MIDDLE GA BUT ISOLD TSRA STILL LIKELY OVER MUCH OF NORTH GA. DUE TO EXPECTED ISOLD COVERAGE...WILL NOT BE ABLE TO ADD TEMPO TO AFTERNOON FCST AT THIS TIME. SNELSON //ATL CONFIDENCE...12Z UPDATE... LOW CONFIDENCE ON CIGS AND SKY COVER THIS MORNING. MEDIUM CONFIDENCE ON TSRA LIKELIHOOD. HIGH CONFIDENCE ON ALL OTHER ELEMENTS. SNELSON && .PRELIMINARY POINT TEMPS/POPS... ATHENS 87 69 86 67 / 40 30 60 40 ATLANTA 86 71 85 70 / 30 30 50 20 BLAIRSVILLE 84 66 82 63 / 30 30 60 40 CARTERSVILLE 88 68 88 67 / 20 20 40 20 COLUMBUS 88 71 89 71 / 50 30 40 20 GAINESVILLE 85 69 85 67 / 30 30 60 30 MACON 87 71 86 68 / 50 40 60 30 ROME 90 68 89 67 / 20 20 40 20 PEACHTREE CITY 86 68 85 67 / 40 30 40 20 VIDALIA 84 72 83 70 / 80 70 70 50 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DEESE LONG TERM....01 AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
645 AM CDT MON MAY 28 2012 .UPDATE... LATEST RADAR LOOP SHOWED A LINE OF ELEVATED SHOWERS AND A FEW THUNDERSTORMS REACHING FROM MANCHESTER THROUGH CEDAR RAPIDS TO JUST WEST OF FAIRFIELD WITH A SECOND LINE FROM WATERLOO TO CENTERVILLE. THESE SHOULD CONTINUE TO WEAKEN WITH THE DIURNAL WANING OF THE LOW LEVEL JET AND ASSOCIATED THETEA ADVECTION. HOWEVER...WITH SUPPORT FROM A DISTINCT MID LEVEL SHORTWAVE AND DRY SLOT LIFTING INTO SE AND EAST CENTRAL IA...WILL EXPECT AT LEAST A COUPLE MORE HOURS OF WEAKENING SHOWERS AND AT LEAST ISOLATED THUNDERSTORMS TO OVERSPREAD EASTERN IA INTO FAR NW IL. LATEST RAP AND HRRR HIGH RES MODELS GENERALLY SUGGEST THIS. THE LIMITED COVERAGE APPEARS TO BE HANDLED BY THE CHANCE POPS IN THE FORECAST FOR THIS MORNING. WILL CONTINUE TO REEVALUATE THE POTENTIAL FOR NEW CONVECTION ALONG THE ADVANCING SURFACE BOUNDARY IN WESTERN IA WITH THE NEW UPPER AIR DATA AND MODEL RUNS THIS MORNING. && .AVIATION... SOUTHWEST WINDS AROUND 40 KTS AROUND 2000 FT AGL WILL CONTINUE TO RESULT IN LOW LEVEL WIND SHEAR UNTIL LOW LEVEL WINDS BEGIN TO MIX MORE UNIFORMLY WITHIN A COUPLE HOURS AFTER SUNRISE. HAVE THUS CONTINUED LLWS IN THE TAFS UNTIL 13Z. SCATTERED...HIGH BASED SHOWERS AND THUNDERSTORMS ADVANCING INTO EAST CENTRAL IA WILL LIKELY IMPACT THE TERMINALS WITH MVFR VSBYS AND GUSTY WINDS BEFORE 17Z. THERE WILL BE ANOTHER CHANCE FOR THUNDERSTORMS IN THE AFTERNOON AS A COLD FRONT MOVES THROUGH THE REGION. HOWEVER... THESE THUNDERSTORMS ARE NOT INCLUDED IN THE FORECAST DUE TO LOW CONFIDENCE IN THE TIMING AND PLACEMENT. THE FRONT SHOULD BE EAST OF ALL TERMINALS BY EARLY EVENING...WHICH WILL VEER THE SOUTHWEST WINDS TO WEST AND DIMINISH SPEEDS TO LESS THAN 10 KTS. CLEAR SKIES AND VFR CONDITIONS WILL THEN BE IN PLACE FOR TONIGHT. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SHEETS
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1050 AM CDT MON MAY 28 2012 .UPDATE... LACKING SOME CONFIDENCE IN THE FORECAST TODAY DUE TO THE WIDESPREAD OVC STRATUS AND SOME DENSE FOG THAT DEVELOPED THIS MORNING ACROSS MUCH OF THE CENTRAL AND EASTERN FA. TEMPERATURES...SKY COVER...AND POSSIBLE AFTERNOON/EVENING THUNDERSTORMS WILL BE AFFECTED BY HOW QUICKLY THE STRATUS CAN LIFT AND CLEAR UP TODAY. THE MODELS STILL SUGGEST WESTERLY WINDS WILL DEVELOP LATER THIS MORNING...AND IT DOES APPEAR THAT THEY ARE BEGINNING TO IN THE AREAS OF THE STRATUS. THEREFORE...ONLY SLIGHTLY DECREASED THE HIGH TEMPERATURES IN THE AREAS THAT HAD THE STRATUS THIS MORNING...AND WILL STILL EXPECT MORE RAPID WARMING THIS AFTERNOON WHEN THERE IS SOME CLEARING. WILL CONTINUE TO COVER THE FOG WITH NOWCASTS IF THE FOG PERSISTS PAST NOON. STORM PREDICTION CENTER REVISED THEIR DAY 1 SLIGHT RISK OF SEVERE WEATHER...WHICH HAD PREVIOUSLY ONLY SKIRTED OUR FAR SE FA...TO NOW INCLUDE MUCH OF THE SOUTHERN FA. THIS DOES SEEM PLAUSIBLE CONSIDERING THE MODELS SUGGEST SURFACE AND ML CAPE OF 500 TO 1500 J/KG DEVELOPING THIS AFTERNOON ACROSS THE SOUTHERN FA. THE NAME INDICATES DEEP LAYER SHEAR (0-6 KM) WILL BE ABOUT 30 TO 40 KNOTS...SO THERE COULD BE SOME ORGANIZATION TO THE STORMS. THE MAIN THREATS SHOULD BE HAIL...WIND...AND BRIEF HEAVY RAIN. THINK IT WILL DEPEND ON HOW MUCH CLEARING THERE IS THIS AFTERNOON TO BUILD UP THE INSTABILITY. THE WRF AND HRRR RUNS HAVE INDICATED A BAND OF SHOWERS/STORMS MOVING INTO THE WESTERN FA MID TO LATE AFTERNOON...AND THEN MOVING INTO THE CENTRAL AND EASTERN FA INTO THIS EVENING. && .HYDROLOGY... ELEVATED WATER LEVELS ARE OCCURRING OR FORECASTED ALONG SEVERAL RIVER FORECAST LOCATIONS IN THE NORTHLAND...AND FOLLOWUP STATEMENTS WERE ISSUED THIS MORNING. ALLOWED SOME AREAL FLOOD WARNINGS FOR PORTIONS OF EAST CENTRAL MINNESOTA TO EXPIRE...BUT CONTINUED AN URBAN AND SMALL STREAM ADVISORY DUE TO EMERGENCY MANAGERS REPORTING SOME FLOODED ROADS IN CROW WING AND AITKIN COUNTIES. WILL LOOK MORE INTO THE NEED TO CONTINUE THE AREAL FLOOD WARNINGS IN THE SOUTH CENTRAL FA THIS AFTERNOON. && .PREV DISCUSSION... /ISSUED 626 AM CDT MON MAY 28 2012/ AVIATION...12Z TAFS RAIN WAS DIMINISHING ACROSS THE NORTHLAND THIS MORNING...WITH IFR CONDITIONS ACROSS THE NORTH...AND SOME PATCHY IFR CONDITIONS SOUTH AS WELL. WEST-SOUTHWEST WINDS WILL DEVELOP TODAY...AND SHOULD SCOUR OUT MUCH OF THE IFR CONDITIONS. HOWEVER...COLDER TEMPS ALOFT WILL LEAD TO A CUMULUS DECK...WITH LOW VFR OR MVFR CEILINGS RESULTING. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE...MAINLY THIS AFTERNOON AND EARLY EVENING. MVFR WITH POCKETS OF IFR CEILINGS WILL OCCUR/MOVE IN TONIGHT WITH THE UPPER TROUGH OVERHEAD. PREV DISCUSSION... /ISSUED 606 AM CDT MON MAY 28 2012/ UPDATE... CANCELED THE FLASH FLOOD WATCH AS THE HEAVY RAIN HAS DISSIPATED ACROSS THE AREA AND THE MAIN THREAT FOR WIDESPREAD FLASH FLOODING HAS ENDED THIS MORNING. ALSO ADDED PATCHY DENSE FOG TO THE FORECAST FOR THIS MORNING. WAS ON THE FENCE CONCERNING A DENSE FOG ADVISORY. HOWEVER THE NEXT COUPLE HOURS OF RECENT RAP MODEL RUNS CONSISTENTLY INDICATE THE FOG SHOULD LIFT AND DISSIPATE AS THE SW WINDS RAMP UP AND MIX OUT THE LOW LEVEL MOISTURE FAIRLY RAPIDLY. SHOULD SEE MOST OF THE FOG LIFT BY 8-9 AM THIS MORNING. PREV DISCUSSION... /ISSUED 322 AM CDT MON MAY 28 2012/ SHORT TERM... TODAY THROUGH TUESDAY AFTERNOON... MAIN CHALLENGES IN THE SHORT TERM ARE FOCUSED AROUND THE SHOWERS AND STORMS MOVING NWD THROUGH THE REGION THIS MORNING...WITH THE POTENTIAL FOR ADDITIONAL LOCALIZED FLOODING...AND THEN ANOTHER ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING OVER N-CENTRAL MN AND MOVING EWD THROUGH THE NORTHLAND THIS AFTERNOON AND EVENING. WILL ALSO SEE ADDITIONAL CHANCES FOR COOL RAIN SHOWERS ACROSS THE FORECAST AREA TONIGHT AND THROUGH THE DAY TUESDAY. AN ARRAY OF FLOOD PRODUCTS ARE CURRENTLY IN EFFECT THIS MORNING...THROUGH THE DAY TODAY...MAINLY ACROSS THE SOUTHERN/SWRN COUNTIES OF THE NORTHLAND...WHICH HAVE RECEIVED THE MOST RAIN THROUGH THE LAST COUPLE DAYS. AS OF 3 AM THIS MORNING...HAVE ALREADY SEEN THE HEAVIEST RAIN SHOWERS WEAKEN AND LIFT TO THE NORTH...WITH SIGNIFICANT DIMINISHING OF THUNDERSTORMS ACROSS SRN MN AS WELL. AT THIS POINT...NOT EXPECTING TO SEE THE VERY HEAVY RAINFALL SEEN EARLIER TONIGHT AND LAST NIGHT THIS MORNING...SHOULD MAINLY BE LIGHT TO OCCASIONALLY MDT SHOWERS AND ISOLATED T-STORMS THROUGH THE REST OF TODAY. THERE IS CURRENTLY A NARROW AXIS OF 700MB F-GEN SITUATED ACROSS SWRN MN/NWRN IA...THAT IS PROGGED TO LIFT NWD INTO NE MN THIS MORNING. THERE IS THE POSSIBILITY THAT ADDITIONAL SIGNIFICANT RAINFALL COULD DEVELOP ASSOCIATED WITH THIS F-GEN BAND. SO...AT THIS TIME WILL CONTINUE WITH THE BROAD FLASH FLOOD WATCH THROUGH 7 AM THIS MORNING...AND RE-EVALUATE THE SITUATION PRIOR TO EITHER CANCELING OR EXTENDING THE WATCH THIS MORNING. SYNOPTIC SET UP SHOWS THE UPPER LOW LIFTING NWD INTO SRN MANITOBA THIS MORNING AS THE ELONGATED SFC TROUGH/COLD FRONT CONTINUES TO MOVE E/NEWD THROUGH CENTRAL/ERN MN. THERE IS A SECONDARY SFC LOW CO-LOCATED WITH THE UPPER LOW THAT WILL EVENTUALLY MOVE EWD ACROSS ND TODAY AND TONIGHT...AND AID IN THE RE-ENFORCEMENT OF ADDITIONAL SHOWERS AND THUNDERSTORMS TODAY...AND MAINLY SHOWERS TONIGHT. IT APPEARS THAT THERE WILL BE ENOUGH LINGERING INSTABILITY COMBINED WITH SLIGHTLY COOLER TEMPERATURES ALOFT AND WARM SFC TEMPS TO STEEPEN LAPSE RATES ENOUGH TO TRIGGER SCATTERED SHOWERS AND T-STORMS THIS AFTERNOON. ALTHOUGH SHOULD SEE A RAPID DECREASE IN ACTIVITY CLOSER TO SUNSET AS THE BNDY LAYER BECOMES MORE STABLE. THE UPPER LOW WILL LAG SLIGHTLY BEHIND THE EWD MOVEMENT OF THE SECONDARY SFC LOW TOMORROW...AND HAVE NOTICEABLY COOLER AIR ASSOCIATED WITH IT. WHILE MUCH OF THE NORTHLAND TODAY WILL SEE WINDS SHIFT TO THE SW AND TEMPERATURES CLIMB INTO THE UPPER 60S NORTH AND 70S TO THE SOUTH...TUESDAY WILL BE A MUCH DIFFERENT STORY AS A COLD AIR MASS BLASTS IN FROM THE NW. A RATHER COOL...IF NOT COLD LATE SPRING DAY IS IN STORE TUESDAY WITH HIGHS ONLY INTO THE UPPER 40S AND LOWER 50S ACROSS MUCH OF THE REGION AND A FEW LOWER 60S INTO NRN WI. THE STIFF NW WINDS AND CLOUDY SKIES WILL MAKE IT FEEL EVEN COLDER THAN THAT AT TIMES. LONG TERM... TUESDAY NIGHT THROUGH SUNDAY... PORTIONS OF OUR EASTERN CWA WILL STILL BE INFLUENCED BY AN UPPER TROUGH TUESDAY NIGHT ALONG WITH COLD TEMPERATURES. BOTH THE GFS AND ECMWF FORECAST 850MB TEMPS OF ZERO TO -3C OVER OUR CWA TUESDAY NIGHT. SOME LIGHT RAIN WILL BE POSSIBLE OVER THE EASTERN ZONES TUESDAY NIGHT...AND BOUNDARY LAYER TEMPS SHOULD BE TOO WARM FOR ANY SNOW TO MIX IN. HIGH PRESSURE NOSES INTO THE CWA WEDNESDAY AND IT SHOULD BE DRY. THE MODELS DIVERGE WEDNESDAY NIGHT INTO THURSDAY IN THE WAY THEY HANDLE AN UPPER LOW. THE ECMWF IS MUCH FURTHER NORTH THAN THE GFS. THE ECMWF HAS THE LOW OVER MINNESOTA...VERSUS THE GFS WHICH DIVES IT WELL SOUTH TO WHERE NE/IA/KS/MO MEET. WE WENT DRY WEDNESDAY NIGHT...BUT INTRODUCED SOME SMALL POPS FOR THURSDAY ACROSS THE SOUTH...WHICH IS CLOSER TO THE ECMWF. AFTER THE UPPER LOW SLIDES EAST...THE REGION GETS INTO NORTHWEST FLOW ALOFT FOR FRIDAY THROUGH SUNDAY WITH A COUPLE SHORTWAVES MOVING THROUGH BRINGING PERIODIC CHANCES FOR LIGHT RAIN. LOW PRESSURE WILL BE MOVING INTO THE NORTHERN PLAINS SUNDAY...AND WARM AIR ADVECTION AHEAD THIS SYSTEM AND A SHORTWAVE WILL BRING A BETTER CHANCE FOR SHOWERS/STORMS INTO THE CWA SUNDAY. TEMPERATURES WILL START QUITE COOL WITH SOME AREAS TUESDAY NIGHT DROPPING TO NEAR FREEZING. HIGHS WEDNESDAY IN THE MID FIFTIES TO AROUND SIXTY WILL INTO THE LOWER TO MID SEVENTIES BY NEXT SUNDAY. && .POINT TEMPS/POPS... DLH 69 47 54 38 / 50 30 30 10 INL 66 43 49 33 / 50 60 50 10 BRD 74 49 55 39 / 40 10 30 10 HYR 78 48 59 37 / 30 40 40 10 ASX 73 50 58 40 / 30 50 40 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ SHORT TERM...GROCHOCINSKI LONG TERM....GSF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1002 AM CDT MON MAY 28 2012 .DISCUSSION... VISIBLE IMAGERY SHOWS MOSTLY SUNNY SKIES ACROSS THE AREA AT THE CURRENT TIME. SOME LINGERING CLOUDS CAN BE FOUND EXTENDING FROM WESTERN LAKE SUPERIOR SOUTH THROUGH THE EASTERN METRO AREA... IN ASSOCIATION WITH A VORTICITY LOBE SEEN IN WATER VAPOR IMAGERY AND THE LATEST RAP ANALYSIS. AN AREA OF CLOUDS AND DYING CONVECTION CAN BE FOUND OVER NORTHWEST MINNESOTA. FORCING HAS RUN OUT AHEAD OF THIS ACTIVITY... SO ALTHOUGH IT MAY FESTER FOR A BIT MOST INDICATIONS ARE THAT IT SHOULD WEAKEN/DIE OVERALL... AT LEAST FOR A LITTLE WHILE. SURFACE ANALYSIS SHOWS AN INITIAL PRE-FRONTAL TROUGH COINCIDENT WITH THE EASTERN CLOUD BAND... AND THE ACTUAL COLD FRONT LIKELY EXTENDING FROM NEAR THE DAKOTA BORDER SOUTH INTO EASTERN NEBRASKA... WHERE A GOOD DEWPOINT GRADIENT CAN BE FOUND. THIS WILL MARCH EAST THROUGH THE DAY TODAY... WITH THE UPPER LOW ALSO SLIDING EAST AND AN LOBE OF UPPER LEVEL PV WORKING INTO WESTERN AND CENTRAL MINNESOTA DURING THE AFTERNOON. THE VARIOUS CONVECTION ALLOWING MODELS... INCLUDING THE HRRR... SPC/EMC WRFNMM... LOCAL WRFARW... AND NSSL WRFARW... ALL SUGGEST A RE- DEVELOPMENT OF CONVECTION NEAR THE SECONDARY FRONTAL BOUNDARY AS IT SWEEPS EAST THROUGH THE FORECAST AREA THIS AFTERNOON INTO EARLY THIS EVENING. AN AXIS OF MLCAPE AOA 1000 J/KG WILL PRECEDE THE BOUNDARY... ALONG WITH DEEP LAYER SHEAR AOA 35 KT. LOW LEVEL SHEAR LOOKS TO BE MEAGER... WHICH SHOULD KEEP A WIDESPREAD DAMAGING WIND THREAT IN CHECK. BUT WILL FREEZING LEVEL HEIGHTS DROPPING AS MID- LEVEL COLD AIR WORKS ACROSS THE REGION... EXPECT SOMEWHAT ORGANIZED STORMS RESULTING FROM THE COMBINATION OF DECENT MLCAPE AND DEEP LAYER SHEAR TO PRODUCE SOME LARGE HAIL ACROSS THE AREA. THE PRIMARY THREAT WILL BE NORTH OF A LINE FROM AROUND LITCHFIELD TO LADYSMITH... MAINLY FROM 2 PM TO 7 PM. ANY DECENT STORM COULD PRODUCE SOME SMALL HAIL GIVEN THE CHILLY TEMPERATURES ALOFT... WHILE ANYTHING THAN MANAGES TO TAKE ADVANTAGE OF THE DEEP LAYER SHEAR AND BETTER ORGANIZE ITSELF COULD PRODUCE HAIL GREATER THAN AN INCH IN DIAMETER. MADE SOME MINOR ADJUSTMENTS TO THE GOING FORECAST WITH RESPECT TO TIMING AND LOCATION OF POPS... WITH SOME ADDITIONAL ADJUSTMENTS LIKELY THROUGH THE DAY AS THINGS START TO TAKE SHAPE. FORECAST HIGHS WILL NEED SOME ADJUSTMENTS GIVEN CURRENT OBS/TRENDS... PARTICULARLY OUT WEST WHERE THE BOUNDARY HASN/T SLIPPED THROUGH YET. && .AVIATION... /12Z TAF ISSUANCE/ /ISSUED 628 AM CDT MON MAY 28 2012/ SCATTERED SHOWERS WILL BE IN THE VICINITY OF KEAU AT TAF ISSUANCE WITH RAPID MOVEMENT TO THE NORTHEAST. SMALL THREAT ACROSS THE TWIN CITIES AND INTO KRNH FOR BKN IFR CEILINGS THROUGH 15Z. CLEARING HAS OCCURRED INTO WEST CENTRAL MN. HOWEVER...INSTABILITY APPROACHING FROM THE CENTRAL DAKOTAS WILL CAUSE A FEW SHOWERS AND THUNDERSTORMS FROM 15-18Z ACROSS CENTRAL MN INCLUDING KAXN AND KSTC. THE ACTIVITY MAY EXTEND AS FAR SOUTH AS KRWF BUT CONFIDENCE NOT HIGH. WESTERLY WINDS WILL BE ON THE INCREASE BY NOON WITH 13 TO 16 KNOT SUSTAINED WINDS LIKELY WITH GUSTS UP TO 25 KNOTS. A FEW SHOWERS AND THUNDERSTORMS MAY DEVELOP AFTER 21Z AROUND THE TWIN CITIES AND SPREAD ACROSS WEST CENTRAL WI THROUGH 00Z. SCT-BKN VFR CLOUDS TONIGHT ALONG WITH WEST WINDS AROUND 10 KNOTS. KMSP...SMALL THREAT EARLY ON FOR BKN IFR CEILINGS...WITH BETTER CHANCES NORTH OF THE METRO. MID LEVEL CEILINGS WILL DIMINISH AFTER 15Z WITH SCT CONDITIONS OCCURRING. INSTABILITY APPROACHING FROM THE WEST THIS AFTERNOON SHOULD RESULT IN A FEW SHOWERS AND THUNDERSTORMS IN THE 21-24Z TIME FRAME. WEST WINDS NEAR 15 KNOTS THIS AFTERNOON WITH GUSTS NEAR 25 KNOTS. WEST WINDS DIMINISHING TO 10 KNOTS TONIGHT ALONG WITH SCT-BKN VFR CLOUDS. /OUTLOOK/ TUESDAY...VFR WITH A FEW AFTERNOON SHOWERS. WNW WINDS 15-20KTS. WEDNESDAY...VFR. N WINDS 5 TO 10KTS. THURSDAY...VFR WITH A FEW SHOWERS. NE WINDS 5 TO 10KTS. && .PREV DISCUSSION... /ISSUED 413 AM CDT MON MAY 28 2012/ AFTER AN ACTIVE NIGHT WITH SEVERE WEATHER AND FLOODING RAINS...THINGS HAVE QUIETED DOWN ACROSS THE CWA. COULD SEE A FEW SHOWERS AND THUNDERSTORMS TODAY...WITH COOLER WEATHER IN STORE FOR THIS UPCOMING WEEK. TODAY AND TUESDAY...EARLY MORNING WATER VAPOR IMAGERY SHOWED A BEAUTIFUL OCCLUDED UPPER LEVEL LOW OVER THE MT/ND BORDER...WITH RAP H500 MINIMUM TEMP ANALYZED AT -23C. AS THIS UPPER LEVEL LOW MOVES EASTWARD TODAY...COLDER MID LEVEL TEMPS WILL SPREAD ACROSS THE REGION RESULTING IN DYNAMIC DESTABILIZATION. IN ADDITION TO THE COOLING TEMPS ALOFT...AFTERNOON HEATING SHOULD ELIMINATE ANY CIN...AND SOUNDINGS SHOW THE POTENTIAL FOR A FEW HIGH BASED SHOWERS AND THUNDERSTORMS TODAY. IN FACT...THIS PHENOMENON WAS RESPONSIBLE FOR THE SHOWERS AND THUNDERSTORMS ACROSS SOUTH DAKOTA THIS MORNING. THEREFORE...HAVE INCREASED POPS ACROSS THE NORTHERN AND WESTERN CWA TODAY. THE WELL MIXED BOUNDARY LAYER AS INDICATED BY THE INVERTED-V FORECAST SOUNDINGS WOULD SUPPORT THE POTENTIAL FOR A FEW STRONGER WIND GUSTS WITH THESE SHOWERS AND THUNDERSTORMS. USED 3HR GRIDS TO SHOWS THE POPS DECREASING AFTER SUNSET...ONLY TO RETURN TOMORROW AFTERNOON. ALSO...WEST NORTHWEST WIND WILL BE BREEZY DURING THE AFTERNOON...BUT SHOULD REMAIN BELOW ADVISORY CRITERIA. WEDNESDAY THROUGH THE WEEKEND...AN UPPER LEVEL WAVE CURRENTLY OF THE BRITISH COLUMBIA COAST WILL CROSS THE NORTHERN ROCKIES TOMORROW AND SLIDE SOUTHEAST DOWN THE MISSOURI RIVER VALLEY. THIS CLIPPER-LIKE SYSTEM WILL ALLOW CANADIAN HIGH PRESSURE TO BUILD ACROSS THE REGION...WITH TEMPERATURES WELL BELOW NORMAL FOR THE MIDDLE OF THE WEEK. AS THE UPPER LEVEL WAVE CONTINUES ON ITS SOUTHEASTWARD MARCH TOWARD THE SOUTHERN PLAINS...THE FORCING ASSOCIATED WITH IT WILL CAUSE A SURFACE LOW PRESSURE SYSTEM TO DEVELOP. THIS WILL LIKELY RESULT IN SEVERE WEATHER ACROSS THE SOUTH CENTRAL US...AND CLOUDY SKIES WITH COOLER TEMPS AND A FEW SCATTERED SHOWERS OVER THE UPPER MIDWEST...ESPECIALLY NEAR THE IA/MN/WI BORDER. THE ECMWF 28.00 IS SLIGHTLY MORE PROGRESSIVE THAN THE GEM OR GFS...BUT EITHER WAY IT LOOKS LIKE THURSDAY AND FRIDAY WILL FEEL MORE LIKE MID APRIL THAN LATE MAY. ONCE THIS LOW MOVES EASTWARD FOR THE WEEKEND...NORTHWEST FLOW WILL SET UP ACROSS THE REGION RESULTING IN WARMER TEMPERATURES CLOSER TO THE SEASON AVERAGE FOR EARLY JUNE. MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. $$ && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ /RAH/JRB
AREA FORECAST DISCUSSION
NWS DULUTH MN
626 AM CDT MON MAY 28 2012 .AVIATION...12Z TAFS RAIN WAS DIMINISHING ACROSS THE NORTHLAND THIS MORNING...WITH IFR CONDITIONS ACROSS THE NORTH...AND SOME PATCHY IFR CONDITIONS SOUTH AS WELL. WEST-SOUTHWEST WINDS WILL DEVELOP TODAY...AND SHOULD SCOUR OUT MUCH OF THE IFR CONDITIONS. HOWEVER...COLDER TEMPS ALOFT WILL LEAD TO A CUMULUS DECK...WITH LOW VFR OR MVFR CEILINGS RESULTING. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE...MAINLY THIS AFTERNOON AND EARLY EVENING. MVFR WITH POCKETS OF IFR CEILINGS WILL OCCUR/MOVE IN TONIGHT WITH THE UPPER TROUGH OVERHEAD. && .PREV DISCUSSION... /ISSUED 606 AM CDT MON MAY 28 2012/ UPDATE... CANCELED THE FLASH FLOOD WATCH AS THE HEAVY RAIN HAS DISSIPATED ACROSS THE AREA AND THE MAIN THREAT FOR WIDESPREAD FLASH FLOODING HAS ENDED THIS MORNING. ALSO ADDED PATCHY DENSE FOG TO THE FORECAST FOR THIS MORNING. WAS ON THE FENCE CONCERNING A DENSE FOG ADVISORY. HOWEVER THE NEXT COUPLE HOURS OF RECENT RAP MODEL RUNS CONSISTENTLY INDICATE THE FOG SHOULD LIFT AND DISSIPATE AS THE SW WINDS RAMP UP AND MIX OUT THE LOW LEVEL MOISTURE FAIRLY RAPIDLY. SHOULD SEE MOST OF THE FOG LIFT BY 8-9 AM THIS MORNING. PREV DISCUSSION... /ISSUED 322 AM CDT MON MAY 28 2012/ SHORT TERM... TODAY THROUGH TUESDAY AFTERNOON... MAIN CHALLENGES IN THE SHORT TERM ARE FOCUSED AROUND THE SHOWERS AND STORMS MOVING NWD THROUGH THE REGION THIS MORNING...WITH THE POTENTIAL FOR ADDITIONAL LOCALIZED FLOODING...AND THEN ANOTHER ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING OVER N-CENTRAL MN AND MOVING EWD THROUGH THE NORTHLAND THIS AFTERNOON AND EVENING. WILL ALSO SEE ADDITIONAL CHANCES FOR COOL RAIN SHOWERS ACROSS THE FORECAST AREA TONIGHT AND THROUGH THE DAY TUESDAY. AN ARRAY OF FLOOD PRODUCTS ARE CURRENTLY IN EFFECT THIS MORNING...THROUGH THE DAY TODAY...MAINLY ACROSS THE SOUTHERN/SWRN COUNTIES OF THE NORTHLAND...WHICH HAVE RECEIVED THE MOST RAIN THROUGH THE LAST COUPLE DAYS. AS OF 3 AM THIS MORNING...HAVE ALREADY SEEN THE HEAVIEST RAIN SHOWERS WEAKEN AND LIFT TO THE NORTH...WITH SIGNIFICANT DIMINISHING OF THUNDERSTORMS ACROSS SRN MN AS WELL. AT THIS POINT...NOT EXPECTING TO SEE THE VERY HEAVY RAINFALL SEEN EARLIER TONIGHT AND LAST NIGHT THIS MORNING...SHOULD MAINLY BE LIGHT TO OCCASIONALLY MDT SHOWERS AND ISOLATED T-STORMS THROUGH THE REST OF TODAY. THERE IS CURRENTLY A NARROW AXIS OF 700MB F-GEN SITUATED ACROSS SWRN MN/NWRN IA...THAT IS PROGGED TO LIFT NWD INTO NE MN THIS MORNING. THERE IS THE POSSIBILITY THAT ADDITIONAL SIGNIFICANT RAINFALL COULD DEVELOP ASSOCIATED WITH THIS F-GEN BAND. SO...AT THIS TIME WILL CONTINUE WITH THE BROAD FLASH FLOOD WATCH THROUGH 7 AM THIS MORNING...AND RE-EVALUATE THE SITUATION PRIOR TO EITHER CANCELING OR EXTENDING THE WATCH THIS MORNING. SYNOPTIC SET UP SHOWS THE UPPER LOW LIFTING NWD INTO SRN MANITOBA THIS MORNING AS THE ELONGATED SFC TROUGH/COLD FRONT CONTINUES TO MOVE E/NEWD THROUGH CENTRAL/ERN MN. THERE IS A SECONDARY SFC LOW CO-LOCATED WITH THE UPPER LOW THAT WILL EVENTUALLY MOVE EWD ACROSS ND TODAY AND TONIGHT...AND AID IN THE RE-ENFORCEMENT OF ADDITIONAL SHOWERS AND THUNDERSTORMS TODAY...AND MAINLY SHOWERS TONIGHT. IT APPEARS THAT THERE WILL BE ENOUGH LINGERING INSTABILITY COMBINED WITH SLIGHTLY COOLER TEMPERATURES ALOFT AND WARM SFC TEMPS TO STEEPEN LAPSE RATES ENOUGH TO TRIGGER SCATTERED SHOWERS AND T-STORMS THIS AFTERNOON. ALTHOUGH SHOULD SEE A RAPID DECREASE IN ACTIVITY CLOSER TO SUNSET AS THE BNDY LAYER BECOMES MORE STABLE. THE UPPER LOW WILL LAG SLIGHTLY BEHIND THE EWD MOVEMENT OF THE SECONDARY SFC LOW TOMORROW...AND HAVE NOTICEABLY COOLER AIR ASSOCIATED WITH IT. WHILE MUCH OF THE NORTHLAND TODAY WILL SEE WINDS SHIFT TO THE SW AND TEMPERATURES CLIMB INTO THE UPPER 60S NORTH AND 70S TO THE SOUTH...TUESDAY WILL BE A MUCH DIFFERENT STORY AS A COLD AIR MASS BLASTS IN FROM THE NW. A RATHER COOL...IF NOT COLD LATE SPRING DAY IS IN STORE TUESDAY WITH HIGHS ONLY INTO THE UPPER 40S AND LOWER 50S ACROSS MUCH OF THE REGION AND A FEW LOWER 60S INTO NRN WI. THE STIFF NW WINDS AND CLOUDY SKIES WILL MAKE IT FEEL EVEN COLDER THAN THAT AT TIMES. LONG TERM... TUESDAY NIGHT THROUGH SUNDAY... PORTIONS OF OUR EASTERN CWA WILL STILL BE INFLUENCED BY AN UPPER TROUGH TUESDAY NIGHT ALONG WITH COLD TEMPERATURES. BOTH THE GFS AND ECMWF FORECAST 850MB TEMPS OF ZERO TO -3C OVER OUR CWA TUESDAY NIGHT. SOME LIGHT RAIN WILL BE POSSIBLE OVER THE EASTERN ZONES TUESDAY NIGHT...AND BOUNDARY LAYER TEMPS SHOULD BE TOO WARM FOR ANY SNOW TO MIX IN. HIGH PRESSURE NOSES INTO THE CWA WEDNESDAY AND IT SHOULD BE DRY. THE MODELS DIVERGE WEDNESDAY NIGHT INTO THURSDAY IN THE WAY THEY HANDLE AN UPPER LOW. THE ECMWF IS MUCH FURTHER NORTH THAN THE GFS. THE ECMWF HAS THE LOW OVER MINNESOTA...VERSUS THE GFS WHICH DIVES IT WELL SOUTH TO WHERE NE/IA/KS/MO MEET. WE WENT DRY WEDNESDAY NIGHT...BUT INTRODUCED SOME SMALL POPS FOR THURSDAY ACROSS THE SOUTH...WHICH IS CLOSER TO THE ECMWF. AFTER THE UPPER LOW SLIDES EAST...THE REGION GETS INTO NORTHWEST FLOW ALOFT FOR FRIDAY THROUGH SUNDAY WITH A COUPLE SHORTWAVES MOVING THROUGH BRINGING PERIODIC CHANCES FOR LIGHT RAIN. LOW PRESSURE WILL BE MOVING INTO THE NORTHERN PLAINS SUNDAY...AND WARM AIR ADVECTION AHEAD THIS SYSTEM AND A SHORTWAVE WILL BRING A BETTER CHANCE FOR SHOWERS/STORMS INTO THE CWA SUNDAY. TEMPERATURES WILL START QUITE COOL WITH SOME AREAS TUESDAY NIGHT DROPPING TO NEAR FREEZING. HIGHS WEDNESDAY IN THE MID FIFTIES TO AROUND SIXTY WILL INTO THE LOWER TO MID SEVENTIES BY NEXT SUNDAY. && .POINT TEMPS/POPS... DLH 72 47 54 38 / 50 30 30 10 INL 66 43 49 33 / 60 60 50 10 BRD 74 49 55 39 / 40 10 30 10 HYR 77 48 59 37 / 40 40 40 10 ASX 76 50 58 40 / 50 50 40 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...SMALL CRAFT ADVISORY UNTIL 10 AM CDT THIS MORNING FOR LSZ140>147. && $$ SHORT TERM...TENTINGER LONG TERM....MELDE AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
606 AM CDT MON MAY 28 2012 .UPDATE... CANCELED THE FLASH FLOOD WATCH AS THE HEAVY RAIN HAS DISSIPATED ACROSS THE AREA AND THE MAIN THREAT FOR WIDESPREAD FLASH FLOODING HAS ENDED THIS MORNING. ALSO ADDED PATCHY DENSE FOG TO THE FORECAST FOR THIS MORNING. WAS ON THE FENCE CONCERNING A DENSE FOG ADVISORY. HOWEVER THE NEXT COUPLE HOURS OF RECENT RAP MODEL RUNS CONSISTENTLY INDICATE THE FOG SHOULD LIFT AND DISSIPATE AS THE SW WINDS RAMP UP AND MIX OUT THE LOW LEVEL MOISTURE FAIRLY RAPIDLY. SHOULD SEE MOST OF THE FOG LIFT BY 8-9 AM THIS MORNING. && .PREV DISCUSSION... /ISSUED 322 AM CDT MON MAY 28 2012/ SHORT TERM... TODAY THROUGH TUESDAY AFTERNOON... MAIN CHALLENGES IN THE SHORT TERM ARE FOCUSED AROUND THE SHOWERS AND STORMS MOVING NWD THROUGH THE REGION THIS MORNING...WITH THE POTENTIAL FOR ADDITIONAL LOCALIZED FLOODING...AND THEN ANOTHER ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING OVER N-CENTRAL MN AND MOVING EWD THROUGH THE NORTHLAND THIS AFTERNOON AND EVENING. WILL ALSO SEE ADDITIONAL CHANCES FOR COOL RAIN SHOWERS ACROSS THE FORECAST AREA TONIGHT AND THROUGH THE DAY TUESDAY. AN ARRAY OF FLOOD PRODUCTS ARE CURRENTLY IN EFFECT THIS MORNING...THROUGH THE DAY TODAY...MAINLY ACROSS THE SOUTHERN/SWRN COUNTIES OF THE NORTHLAND...WHICH HAVE RECEIVED THE MOST RAIN THROUGH THE LAST COUPLE DAYS. AS OF 3 AM THIS MORNING...HAVE ALREADY SEEN THE HEAVIEST RAIN SHOWERS WEAKEN AND LIFT TO THE NORTH...WITH SIGNIFICANT DIMINISHING OF THUNDERSTORMS ACROSS SRN MN AS WELL. AT THIS POINT...NOT EXPECTING TO SEE THE VERY HEAVY RAINFALL SEEN EARLIER TONIGHT AND LAST NIGHT THIS MORNING...SHOULD MAINLY BE LIGHT TO OCCASIONALLY MDT SHOWERS AND ISOLATED T-STORMS THROUGH THE REST OF TODAY. THERE IS CURRENTLY A NARROW AXIS OF 700MB F-GEN SITUATED ACROSS SWRN MN/NWRN IA...THAT IS PROGGED TO LIFT NWD INTO NE MN THIS MORNING. THERE IS THE POSSIBILITY THAT ADDITIONAL SIGNIFICANT RAINFALL COULD DEVELOP ASSOCIATED WITH THIS F-GEN BAND. SO...AT THIS TIME WILL CONTINUE WITH THE BROAD FLASH FLOOD WATCH THROUGH 7 AM THIS MORNING...AND RE-EVALUATE THE SITUATION PRIOR TO EITHER CANCELING OR EXTENDING THE WATCH THIS MORNING. SYNOPTIC SET UP SHOWS THE UPPER LOW LIFTING NWD INTO SRN MANITOBA THIS MORNING AS THE ELONGATED SFC TROUGH/COLD FRONT CONTINUES TO MOVE E/NEWD THROUGH CENTRAL/ERN MN. THERE IS A SECONDARY SFC LOW CO-LOCATED WITH THE UPPER LOW THAT WILL EVENTUALLY MOVE EWD ACROSS ND TODAY AND TONIGHT...AND AID IN THE RE-ENFORCEMENT OF ADDITIONAL SHOWERS AND THUNDERSTORMS TODAY...AND MAINLY SHOWERS TONIGHT. IT APPEARS THAT THERE WILL BE ENOUGH LINGERING INSTABILITY COMBINED WITH SLIGHTLY COOLER TEMPERATURES ALOFT AND WARM SFC TEMPS TO STEEPEN LAPSE RATES ENOUGH TO TRIGGER SCATTERED SHOWERS AND T-STORMS THIS AFTERNOON. ALTHOUGH SHOULD SEE A RAPID DECREASE IN ACTIVITY CLOSER TO SUNSET AS THE BNDY LAYER BECOMES MORE STABLE. THE UPPER LOW WILL LAG SLIGHTLY BEHIND THE EWD MOVEMENT OF THE SECONDARY SFC LOW TOMORROW...AND HAVE NOTICEABLY COOLER AIR ASSOCIATED WITH IT. WHILE MUCH OF THE NORTHLAND TODAY WILL SEE WINDS SHIFT TO THE SW AND TEMPERATURES CLIMB INTO THE UPPER 60S NORTH AND 70S TO THE SOUTH...TUESDAY WILL BE A MUCH DIFFERENT STORY AS A COLD AIR MASS BLASTS IN FROM THE NW. A RATHER COOL...IF NOT COLD LATE SPRING DAY IS IN STORE TUESDAY WITH HIGHS ONLY INTO THE UPPER 40S AND LOWER 50S ACROSS MUCH OF THE REGION AND A FEW LOWER 60S INTO NRN WI. THE STIFF NW WINDS AND CLOUDY SKIES WILL MAKE IT FEEL EVEN COLDER THAN THAT AT TIMES. LONG TERM... TUESDAY NIGHT THROUGH SUNDAY... PORTIONS OF OUR EASTERN CWA WILL STILL BE INFLUENCED BY AN UPPER TROUGH TUESDAY NIGHT ALONG WITH COLD TEMPERATURES. BOTH THE GFS AND ECMWF FORECAST 850MB TEMPS OF ZERO TO -3C OVER OUR CWA TUESDAY NIGHT. SOME LIGHT RAIN WILL BE POSSIBLE OVER THE EASTERN ZONES TUESDAY NIGHT...AND BOUNDARY LAYER TEMPS SHOULD BE TOO WARM FOR ANY SNOW TO MIX IN. HIGH PRESSURE NOSES INTO THE CWA WEDNESDAY AND IT SHOULD BE DRY. THE MODELS DIVERGE WEDNESDAY NIGHT INTO THURSDAY IN THE WAY THEY HANDLE AN UPPER LOW. THE ECMWF IS MUCH FURTHER NORTH THAN THE GFS. THE ECMWF HAS THE LOW OVER MINNESOTA...VERSUS THE GFS WHICH DIVES IT WELL SOUTH TO WHERE NE/IA/KS/MO MEET. WE WENT DRY WEDNESDAY NIGHT...BUT INTRODUCED SOME SMALL POPS FOR THURSDAY ACROSS THE SOUTH...WHICH IS CLOSER TO THE ECMWF. AFTER THE UPPER LOW SLIDES EAST...THE REGION GETS INTO NORTHWEST FLOW ALOFT FOR FRIDAY THROUGH SUNDAY WITH A COUPLE SHORTWAVES MOVING THROUGH BRINGING PERIODIC CHANCES FOR LIGHT RAIN. LOW PRESSURE WILL BE MOVING INTO THE NORTHERN PLAINS SUNDAY...AND WARM AIR ADVECTION AHEAD THIS SYSTEM AND A SHORTWAVE WILL BRING A BETTER CHANCE FOR SHOWERS/STORMS INTO THE CWA SUNDAY. TEMPERATURES WILL START QUITE COOL WITH SOME AREAS TUESDAY NIGHT DROPPING TO NEAR FREEZING. HIGHS WEDNESDAY IN THE MID FIFTIES TO AROUND SIXTY WILL INTO THE LOWER TO MID SEVENTIES BY NEXT SUNDAY. AVIATION.../06Z TAF ISSUANCE/ ONGOING SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH DAWN WITH VISIBILITIES FALLING TO MVFR RANGE AND IFR CEILINGS. LOOK FOR CEILINGS TO RISE AFTER 14Z WITH WINDS COMING FROM THE WEST WITH A COLD FRONTAL PASSAGE. HINTED AT SOME FOG FORMATION TOWARDS THE END OF THE TAF PERIOD AT DLH AND HIB. && .POINT TEMPS/POPS... DLH 72 47 54 38 / 50 30 30 10 INL 66 43 49 33 / 60 60 50 10 BRD 74 49 55 39 / 40 10 30 10 HYR 77 48 59 37 / 40 40 40 10 ASX 76 50 58 40 / 50 50 40 20 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...SMALL CRAFT ADVISORY UNTIL 10 AM CDT THIS MORNING FOR LSZ140>147. && $$ SHORT TERM...TENTINGER LONG TERM....MELDE
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
616 AM CDT MON MAY 28 2012 .SHORT TERM... ISSUED AT 319 AM CDT MON MAY 28 2012 (TODAY AND TONIGHT) MAIN CONCERN TODAY WILL BE THE POTENTIAL FOR A FEW SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT. AREA OF SHOWERS AND SCATTERED THUNDERSTORMS OVER WESTERN IOWA SHOULD PROGRESS EASTWARD THIS MORNING. VORT MAX SEEN ON WATER VAPOR IMAGERY OVER CENTRAL NEBRASKA EARLY THIS MORNING SHOULD MOVE NORTHEASTWARD AND WILL SUPPLY LIFT FOR THESE STORMS. ADDITIONAL STORMS MAY DEVELOP AS FAR SOUTH AS NORTHERN MISSOURI AND MOVE INTO NORTHEAST MISSOURI BETWEEN 12-15Z BASED ON LATEST RAP RUN DEPICTING DECENT 925-850MB MOISTURE CONVERGENCE OVER THESE AREAS. CHANCES WILL INCREASE THROUGH THE DAY AS COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS MOVES EASTWARD AND REACHES KUIN-KCOU LINE BY 00Z. MLCAPES BY MID AFTERNOON WILL BE IN THE 1500-2500 J/KG RANGE WITH LIMITED CINH. STILL DOES NOT LOOK LIKE THERE WILL BE MUCH LOW LEVEL CONVERGENCE OR LARGE SCALE ASCENT CAUSE BY A SHORTWAVE TO FORCE WIDESPREAD DEVELOPMENT. SO AREA EXTENT OF STORMS STILL LOOKS TO BE SCATTERED UNLESS COLD POOLS CAN ORGANIZE AND FORCE MORE WIDESPREAD COVERAGE. DEEP LAYER SHEAR STILL ONLY LOOKS TO BE IN THE 25-35 KT RANGE WHICH FAVORS MULTICELLS...THOUGH AMOUNT OF CAPE STILL SUGGEST THE POTENTIAL FOR DAMAGING WIND GUSTS AND SOME LARGE HAIL INTO THE EVENING. COLD FRONT WILL CLEAR THE CWA LATE TONIGHT...SO SHOWERS AND THUNDERSTORMS WILL END FROM NORTHWEST TO SOUTHEAST AFTER MIDNIGHT. TEMPERATURES HAVE MOSTLY BEEN AT OR BELOW FORECAST MOS GUIDANCE THE PAST TWO DAYS...AND DO NOT EXPECT THEM TO EXCEED THESE VALUES TODAY GIVEN MORE CLOUDS. BRITT && .LONG TERM... ISSUED AT 412 AM CDT MON MAY 28 2012 (TUESDAY THROUGH SUNDAY) LOOKS LIKE THE PRECIPITATION SHOULD PUSH SE OF OUR FORECAST AREA BY TUE AS THE COLD FRONT MOVES SE OF THE AREA WITH A SFC RIDGE BUILDING SEWD INTO MO. TEMPERATURES WILL BE COOLER TUE THROUGH WED WITH LOW LEVEL CAA...ALTHOUGH STILL ABOVE NORMAL ON TUE. ELEVATED CONVECTION SHOULD MOVE INTO THE AREA WED NGT AS THE NAM MODEL DEPICTS STRONG 850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE OVER CNTRL MO ON NOSE OF S-SWLY LOW LEVEL JET. MODELS SHOWING A GOOD CHANCE OF WIDESPREAD SHOWERS AND STORMS ON THU AS AN UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE EWD THROUGH THE REGION. THE GFS MODEL IS FURTHER S WITH THE MAIN UPPER LEVEL LOW VERSUS THE ECMWF SOLUTION AND IS ALSO LESS PROGRESSIVE WITH THE UPPER LEVEL LOW AND ASSOCIATED PRECIPITATION. FOR NOW WILL GO WITH THE MORE PROGRESSIVE ECMWF SOLUTION WHICH APPEARS MORE REALISTIC FOR THIS TIME OF YEAR AND MORE LIKELY TOO VERIFY THAN THE GFS. WILL END THE POPS OR LOWER THEM DRAMATICALLY BY FRI AS THE UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE E OF OUR AREA. TEMPERATURES WILL BE COLDER AND BELOW NORMAL ON THU MAINLY DUE TO CLOUDS AND PRECIPITATION AND CONTINUED RELATIVELY COLD THU NGT AND FRI WITH NLY WINDS BRINGING COLDER AIR INTO THE REGION BEHIND THE 850MB/SFC LOW. THE ECMWF MODEL DROPS THE 4 DEGREE C 850 MB ISOTHERM SWD TO STL BY 12Z FRI. TEMPERATURES WILL BEGIN TO MODERATE THIS WEEKEND AS UPPER LEVEL HEIGHTS RISE BEHIND THE UPPER LEVEL TROUGH AND THE LOW LEVEL WINDS BECOME MORE S-SWLY BEHIND THE SFC RIDGE. GK`S && .AVIATION... ISSUED AT 615 AM CDT MON MAY 28 2012 SCATTERED THUNDERSTORMS CONTINUE TO DEVELOP ACROSS CENTRAL IOWA AND HAVE RECENTLY DEVELOPED AS FAR SOUTH AS NORTH CENTRAL MISSOURI TO THE NORTHWEST OF KIRK IN THE PAST HALF HOUR. WILL CONTINUE TO MONITOR THIS TREND TO SEE IF IT WILL THREATEN KUIN IN THE NEXT FEW HOURS...OTHERWISE THINK THAT THE BEST CHANCE OF -SHRA/-TSRA AT THE TAF SITES WILL OCCUR LATER THIS AFTERNOON AND THIS EVENING AS A COLD FRONT MOVES ACROSS THE AREA. EXPECT MAINLY VFR CONDITIONS... THOUGH CIGS/VSBYS MAY TEMPORARILY FALL TO MVFR OR PERHAPS IFR IN THUNDERSTORM CORES. A FEW THUNDERSTORMS MAY PRODUCE HAIL OR SEVERE WIND GUSTS. WINDS WILL SHIFT FROM SOUTHWEST TO NORTHWEST BEHIND FROPA. SPECIFICS FOR KSTL...EXPECT SOUTHWEST WINDS TO INCREASE BY MID- MORNING WITH WIND DIRECTION RANGING FROM 200-230 DEGREES TODAY. WINDS WILL THEN SHIFT MORE WESTERLY THIS EVENING WITH THE APPROACH OF A COLD FRONT THAT WILL PASS THROUGH THE TERMINAL JUST AFTER 06Z. THERE IS A CHANCE OF THUNDERSTORMS AHEAD OF THE FRONT THIS EVENING. BRITT && .CLIMATE... ISSUED AT 653 PM CDT MON MAY 21 2012 HERE IS A LIST OF RECORD HIGH TEMPERATURES FOR MONDAY... ...MONDAY... (5/28) ST. LOUIS 93 2006 COLUMBIA 91 2006 QUINCY 94 1914 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
954 AM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT OVER LAKE ERIE WILL MOVE NORTH OF THE LAKE THIS MORNING. A COLD FRONT IS EXPECTED TO ENTER NORTHWEST OHIO LATE TONIGHT AND MOVE ACROSS THE LOCAL AREA ON TUESDAY. HIGH PRESSURE WILL BUILD OVER THE REGION FOR THE MIDDLE PORTION OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... CURRENT FORECAST LOOKS REASONABLE SO ONLY MINOR CHANGES PLANNED. 12Z MORNING SOUNDINGS SUPPORT MAX AFTERNOON TEMPERATURES IN THE MID 90S OVER THE WESTERN COUNTIES WHICH AGREES WITH HRRR HOURLY TEMPERATURES. INSTABILITY IS BUILDING QUICKLY THIS MORNING TO OVER 1000 J/KG IN THE EASTERN COUNTIES BUT CIN IS STILL STRONG WITH VALUES BELOW -150J/KG. BY EARLY AFTERNOON THE CAP MAY BREAK NEAR THE CANTON YNG AREA SO A 20% POP LOOKS REASONABLE. WITH THE WARM FRONT FINALLY LIFTING WELL NORTH OF THE AREA THE PRESSURE GRADIENT IS STRONG ENOUGH TO INHIBIT A LAKE BREEZE. CONSEQUENTLY...LOW LEVEL CONVERGENCE REMAINS DIFFICULT TO DISCERN. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... STORM CHANCES WILL INCREASE OVERNIGHT AS A COLD FRONT MOVES INTO THE REGION. THE FRONT SHOULD ARRIVE IN NW OH TOWARD DAYBREAK AND MOVE ACROSS THE LOCAL AREA BY EARLY TUESDAY AFTERNOON. THIS TIMING SHOULD RESULT IN LITTLE SEVERE WEATHER BECAUSE OF DIURNAL REASONS. IT IS POSSIBLE THAT SOME SEVERE WEATHER COULD OCCUR IN THE FAR WEST LATE TONIGHT BUT THINK THE FRONT WILL BE EAST OF THE AREA BY THE TIME IT GETS REALLY ACTIVE AGAIN. WITH THAT BEING SAID...MOST OF THE AREA SHOULD SEE SHOWERS AND STORMS LATE TONIGHT AND TUESDAY MORNING. WILL GO WITH LIKELY POPS ALL AREAS. A HALF INCH OF RAIN SEEMS LIKELY MOST AREAS. THE PRECIP WILL QUICKLY END FROM W TO E TUESDAY AFTERNOON AS DRY AIR MOVES IN BEHIND THE FRONT. HIGH PRESSURE WILL BUILD IN FROM THE NW TUESDAY NIGHT INTO THURSDAY. THINK THE ATMOSPHERE WILL BE TOO DRY FOR ANY COLD AIR ADVECTION SHOWERS ALTHOUGH SOME LAKE INDUCED STRATO CU APPEARS LIKELY. MODELS NOW SHOWING AN AREA OF LOW PRESSURE MOVING UP THE OHIO VALLEY TOWARD THE END OF THE PERIOD. IT APPEARS THAT SOME WARM AIR ADVECTION PRECIP COULD GET GOING THURSDAY NIGHT...ESPECIALLY ACROSS THE SOUTHERN AND WESTERN END OF THE FORECAST AREA. HAVE USED A BLEND OF GUIDANCE TEMPS DURING THE PERIOD. && .LONG TERM /FRIDAY THROUGH SUNDAY/... THE SLOW MOVING LOW REMAINS ON TRACK TO BE MOVING ACROSS THE AREA FRI INTO SAT. WIDESPREAD SHRA SHOULD OCCUR WITH THE LOW ALONG WITH COLDER THAN NORMAL TEMPS. THE GFS LINGERS THE WRAP AROUND MOISTURE AND SHRA OVER THE AREA SUN WHILE THE ECMWF PULLS THE LOW OFF TO THE NE FASTER BUT STILL SHOWS SOME MOISTURE LEFT AROUND THE AREA. WILL INCREASE POP FOR SAT INTO SUN AND LOWER TEMPS A LITTLE TO ACCOUNT FOR THIS. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... PATCHY MORNING FOG WILL DISSIPATE NEXT HOUR OR TWO. SCT CU WILL DEVELOP AROUND 16 TO 17Z AND BY MID AFTERNOON THERE COULD BE AN ISOLATED SHRA OR TSRA SOMEWHERE AROUND THE AREA BUT CERTAINLY NOT ENOUGH OF A CHANCE TO TRY AND PUT IN TAFS. SOME OF THE SHORT TERM HI RES MODELS SEEM TO BE LEANING TOWARD THE CAK TO YNG AREA FOR THE BETTER POSSIBILITY OF AFTERNOON CONVECTION BUT NOT SURE WHY. THE APPROACH OF A COLD FRONT WILL LEAD TO AN INCREASING CHANCE FOR TSRA TONIGHT...SOME OF WHICH COULD BE STRONG TO SEVERE...ESPECIALLY FOR THE TOL AND FDY AREA. .OUTLOOK...NON VFR POSSIBLE IN SHOWERS/THUNDERSTORMS TUESDAY AND IN WIDESPREAD SHRA FRI. && .MARINE... EVEN THROUGH WINDS WILL PICK UP LATER TODAY THROUGH TONIGHT THE VERY WARM AIR OVER THE COLDER LAKE SHOULD KEEP WINDS ON THE LAKE FROM GETTING ABOVE 15 KNOTS ON AVERAGE. A COLD FRONT WILL CROSS THE LAKE TUE MORNING SHIFTING THE FLOW TO WEST. AS COLDER AIR ARRIVES TUE NIGHT WINDS SHOULD PICK UP AND MAY SEE MARGINAL SCA CONDITIONS DEVELOP AND LAST THRU WED OR WED NIGHT. HIGH PRESSURE ACROSS ONTARIO AND SHOULD DIMINISH THE FLOW FOR A WHILE THU AS WINDS VEER TO NE. THE MODELS BRING A SLOW MOVING LOW NE TOWARD LAKE ERIE THU NIGHT AND FRI. SHOULD SEE NE FLOW INCREASE ENOUGH FOR SCA CONDITIONS TO REDEVELOP. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KUBINA NEAR TERM...REL SHORT TERM...KUBINA LONG TERM...ADAMS AVIATION...ADAMS MARINE...ADAMS
AREA FORECAST DISCUSSION
NWS TULSA OK
945 AM CDT MON MAY 28 2012 .DISCUSSION... MORNING SURFACE MAP SHOWS COLD FRONT FROM CENTRAL KS DOWN INTO WESTERN OK. THE FRONT WILL BE SLOW TO MAKE PROGRESS EAST TODAY...WITH LITTLE IN THE WAY OF UPPER SUPPORT AND NEARLY PARELLEL FLOW ALOFT TO THE BOUNDARY. BAND OF MID CLOUD STRETCHES FROM EASTERN OK UP INTO MO...WHERE SOME ELEVATED SHOWERS AND A FEW LIGHTNING STRIKES HAVE BEEN OBSERVED. THE LATEST SHORT-TERM MODEL GUIDANCE...INCLUDING THE LATEST RUNS OF THE HRRR AND THE 12Z NAM...SUGGEST THAT A FEW ELEVATED SHOWERS AND POSSIBLY A FEW RUMBLES OF THUNDER ARE POSSIBLE THIS AFTERNOON ALONG THIS MOISTURE AXIS ALOFT. OTHERWISE...SURFACE BASED CONVECTION WILL BE INITIATING OVER NW TX OR FAR SW OK BY LATE THIS AFTERNOON NEAR A SURFACE LOW AND AT THE TAIL END OF THE FRONT. THIS CONVECTION WILL PROBABLY CONGEAL INTO AN MCS AND MOVE EAST OR SOUTHEAST ACROSS SOUTHERN OK AND NORTHERN TX TONIGHT. FARTHER NORTH...THE NAM SUGGESTS THAT SCATTERED CONVECTION WILL GET GOING THIS EVENING /AROUND 03Z OR SO/ ROUGHLY ALONG THE I-44 CORRIDOR WHERE THE LOW LVL FRONTAL ZONE WILL BE CO-LOCATED. THE CONVECTION SHOULD GRADUALLY WEAKEN AFTER MIDNIGHT. I HAVE MADE SOME ADJUSTMENTS TO THE TEMPS AND CLOUD COVER...OTHERWISE THE GOING FORECAST APPEARS TO BE ON TRACK. I LEFT THE SLIGHT CHANCE POPS FOR THIS AFTERNOON OVER NORTHEAST OK ALONE FOR REASONS STATED ABOVE. UPDATED PRODUCTS HAVE BEEN SENT. LACY && .PREV DISCUSSION... /ISSUED 617 AM CDT MON MAY 28 2012/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. FOR THE 12 Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGHOUT THE DAY TODAY. MID CLOUDS SHOULD THICKEN UP AS A COLD FRONT APPROACHES NORTHEAST OKLAHOMA LATE AFTERNOON INTO EARLY EVENING. THUNDERSTORM CHANCES WILL INCREASE FROM EARLY EVENING ON AT ALL SITES. PREV DISCUSSION... /ISSUED 323 AM CDT MON MAY 28 2012/ DISCUSSION... SURFACE LOW CURRENTLY MOVING INTO CENTRAL KANSAS EARLY THIS MORNING WITH FRONTAL BOUNDARY EXTENDING SOUTHWEST INTO THE OK/TX PANHANDLES. FRONT WILL PUSH INTO CENTRAL/NORTHEAST OKLAHOMA BY LATE AFTERNOON...MOVING TO NEAR A OKLAHOMA CITY/PONCA CITY LINE BY 00Z. HIGH TEMPERATURES WILL BE DEPENDENT ON AFTERNOON CLOUD COVER AND HOW QUICKLY STORMS FIRE ALONG THE FRONT. FOLLOWED THE WARMER MET GUIDANCE BUT THIS COULD STILL BE TOO COOL GIVEN THE WARM 850 MB TEMPS/LIGHT SOUTHWEST WINDS AHEAD OF BOUNDARY...ESPECIALLY IF THE CLOUD COVER REMAINS LIMITED. SCATTERED SHOWERS/THUNDERSTORMS SHOULD DEVELOP BY EARLY EVENING ALONG STALLED FRONT BEFORE DECREASING IN COVERAGE BY LATE EVENING. A FEW STORMS COULD BRIEFLY REACH SEVERE LIMITS GIVEN THE HIGH SURFACE BASED INSTABILITY EXPECTED...HOWEVER WEAK DEEP LAYER SHEAR SHOULD LIMIT OVERALL SEVERE THREAT. SEVERAL ROUNDS OF PRECIPITATION POSSIBLE TUESDAY THROUGH THURSDAY WITH THE POTENTIAL FOR MULTIPLE THUNDERSTORM COMPLEXES TO TRAVERSE THE REGION. TIMING WILL REMAIN CHALLENGING AND WILL LIKELY PLAY HAVOC ON TEMPERATURE FORECAST DEPENDING ON EXACT MCS EVOLUTION. MODELS IN GENERAL AGREEMENT WITH THE BEST THUNDERSTORM CHANCES WEDNESDAY NIGHT INTO THURSDAY AS UPPER JET STREAK DIVES SSE ALONG THE LEE OF THE ROCKIES. GREATEST SEVERE/HEAVY RAINFALL THREAT WILL LIKELY OCCUR DURING THIS TIME...ALTHOUGH TUESDAY WILL ALSO HAVE AT LEAST A LIMITED SEVERE THREAT WITH ANY MCS ACTIVITY. MAIN UPPER TROUGH WILL BEGIN TO SHIFT EAST OF THE AREA THURSDAY NIGHT INTO FRIDAY WITH PRECIPITATION CHANCES ENDING. GENERALLY WENT WITH A BLEND OF THE WARMER ECMWF/COOLER MEX GUIDANCE THROUGH THE REMAINDER OF THE EXTENDED PERIODS AS SURFACE HIGH SHIFTS EAST BY SUNDAY WITH RETURN FLOW DEVELOPING. && .PRELIMINARY POINT TEMPS/POPS... TUL 91 70 88 67 / 20 40 50 30 FSM 95 69 90 68 / 10 40 50 30 MLC 91 69 88 68 / 10 40 40 40 BVO 93 62 87 64 / 20 30 50 30 FYV 90 63 86 62 / 20 40 50 30 BYV 90 66 85 61 / 20 40 30 30 MKO 91 69 88 67 / 20 40 50 30 MIO 90 65 86 64 / 20 40 40 30 F10 91 69 87 68 / 20 40 50 40 HHW 92 71 90 69 / 10 30 30 40 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...30
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1039 AM CDT MON MAY 28 2012 .UPDATE... INCREASED POPS SOUTHEAST OF A PADUCAH TO POST LINE THIS AFTERNOON BASED ON 12Z MODEL RUNS AND LATEST HI-RES CONVECTION ALLOWING MODELS. ALL PRETTY MUCH IN AGREEMENT ON ISOLD-SCT CONVECTION DEVELOPING ALONG AND SOUTH OF RETREATING WARM FNT THIS AFTER 21Z. FORECAST SOUNDINGS SHOWING SBCAPE IN WARM SECTOR AROUND 1700 J/KG WITH DEEP LAYER SHEAR ON ORDER OF 35KT. UPPER AIR ANALYSIS SHOWS A JET STREAK NEAR TWC @ 12Z WHICH LENGHTENS THE HODOGRAPH SOME THIS EVENING AND SHOULD HELP TO ORGANIZE CONVECTION THAN CAN GET GOING. STRONG CAP THAT HAS BEEN IN PLACE LAST FEW DAYS MAY STILL BE A LIMITING FACTOR TO MORE WIDESPREAD CONVECTION AND EXTENT OF PRECIP ESPECIALLY FURTHER WEST AND NORTH ACROSS THE AREA BUT ENOUGH CONFIDENCE EXISTS IN STORMS TO INCREASE MENTION SOUTHEAST OF LUBBOCK ALONG EDGE OF EML. && .PREV DISCUSSION... /ISSUED 626 AM CDT MON MAY 28 2012/ AVIATION... CLEAR SKIES AND DECLINING SOUTHERLY WINDS MAY POSE A BRIEF THREAT OF VFR-MVFR FOG...PARTICULARLY AT KLBB AS THE LATEST KLBB METAR REPORT VISIBILITY DECREASING TO 7SM AND KCDS REMAINED AT 10SM. HOWEVER...A COLD FRONT WITH WIND SPEEDS AOA 10 MPH IS BEGINNING TO AFFECT KLBB /AND WILL AFFECT KCDS IN THE NEXT HOUR OR SO/ AS A WIND DIRECTION FROM THE WNW WERE REPORTED BY THE LATEST METAR. THE HIGHER WIND SPEEDS MAY MITIGATE FOGGY CONDITIONS AND THUS WILL OPT NOT TO ADD A MENTION. WILL OF COURSE AMEND AS NECESSARY. THE FRONT WILL STALL SOUTH OF THE BOTH TERMINALS THIS AFTERNOON AND WILL BE A FOCUS FOR THUNDERSTORMS TO DEVELOP THIS EVENING. HAVE ADDED A VCTS AND PROB30 MENTION AT KLBB AND KCDS RESPECTIVELY FOR THIS POSSIBILITY. TONIGHT...WINDS WILL BE LIGHT AND VARIABLE FOLLOWED BY A SOUTH WIND TOWARDS THE END OF THE TAF PERIOD. PREV DISCUSSION... /ISSUED 234 AM CDT MON MAY 28 2012/ SHORT TERM... THE BROAD UA LOW CONTINUED TO SLOWLY TRANSLATE ENE TOWARDS THE HIGH PLAINS/SOUTHERN SASKATCHEWAN PER 07Z WATER VAPOR IMAGERY. ITS SOUTHERN PERIPHERY SKIRTED ACROSS THE PANHANDLES WHICH HAS RESULTED IN A BRIEFLY STRONG ISOLATED THUNDERSTORM ACROSS THE EASTERN TEXAS PANHANDLE...THAT HAS SINCE SHIFTED EAST ACROSS WESTERN OKLAHOMA. WHAT IS OF CONCERN IS ADDITIONAL CONVECTION DEVELOPING SOUTH AND EAST OF THE SAID STORM IN THE NEXT COUPLE OF HOURS...COINCIDING WITH A NEARBY PACIFIC FRONT THAT HAS INTERSECTED THE CENTRAL PANHANDLES AND THE FAR NORTHWESTERN SOUTH PLAINS EARLY THIS MORNING. THE FRONT IS EXPECTED TO MOVE SOUTH AND EAST ACROSS THE EASTERN PANHANDLES /AOA 08Z/ AND THEN THE NORTHEASTERN SOUTH PLAINS /AOA 10Z/. A LINGERING RETREATING DRYLINE ACROSS THE SOUTHERN PLAINS WILL BE OVERCOME BY THE FRONT AS IS LIKELY WHY THE HRRR AND GFS SOLUTIONS ARE EAGER TO DISPLAY PRECIP ALONG THIS FRONTAL BOUNDARY.... MORESO BETWEEN 06Z AND 12Z. THE FRONTAL PUSH IS NOT IMPRESSIVELY STRONG BUT IS QUITE DRY WITH 07Z METARS DISPLAYING 15 KT WIND SPEEDS AND SINGLE DIGITS DEWPOINTS ACROSS THE WESTERN PANHANDLES. CURRENT THINKING IS THE BEST SYNOPTIC LIFT IS JUST TOO FAR NORTH AND THE GFS AND HRRR SOLUTIONS DISPLAYING PRECIP NEAR THE SOUTHEASTERN TEXAS PANHANDLE AT 06Z AND 07Z RESPECTIVELY WAS OBVIOUSLY OVER DONE. THUS THE DRY NAM AND ECMWF SOLUTIONS MAY HAVE A BETTER HANDLE ON THE SITUATION AND THUS WILL MAINTAIN SILENT POPS THIS MORNING. THIS AFTERNOON HOWEVER IS A DIFFERENT STORY AS THE UA LOW MARCHES EAST ACROSS NORTHERN MINNESOTA/SOUTHERN ONTARIO...AND THE FRONT PUSHES FARTHER SOUTHEAST TO NEAR THE SERN ZONES WHERE IT IS THERE THAT IT STALLS /FROM NEAR PADUCAH SW TO DENVER CITY/. SOUTHERLY FLOW SOUTH OF THE FRONT WILL CONTINUE TO DRAW IN MID LEVEL MOISTURE AS INDICATED BY PROGGED PWATS OF 1.65 INCHES AND PERSISTING DEWPOINTS IN THE 60S THIS EVENING. AS TEMPS WARM INTO THE UPPER 80S TO LOWER TO MID 90S...THE CAPPING INVERSION WILL WEAKEN AND IS EXPECTED TO BREAK AOA 29/00Z. AS FLOW ALOFT EVOLVES TO NEAR ZONAL FLOW...A SUBTLE EMBEDDED DISTURBANCE IS EXPECTED TO MOVE ACROSS THE SOUTHERN PLAINS THIS EVENING...THUS SERVING AS THE SYNOPTIC SPARK POSSIBLY NEEDED TO INITIATE STORMS...ESPECIALLY WITH AN UNIMPRESSIVE FRONTAL BOUNDARY IN PLACE. SFC-BASED CAPE OF 1.5-2.5 KG/KG...INVERTED-V SOUNDING PROFILES...VEERING WIND PROFILES...A LINGERING FRONTAL BOUNDARY AND SUBTLE LARGE SCALE ASCENT SUGGEST THE PROSPECT FOR STORMS TO APPROACH STRONG LEVELS...AND PERHAPS BE CAPABLE OF ORGANIZATION WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. WILL THEREFORE MAINTAIN MENTIONABLE POPS OFF THE CAPROCK WITH EMPHASIS ACROSS THE SERN ZONES...COMMENCING LATE THIS AFTERNOON AND SHIFT BEST PRECIP EASTWARD BY THE END OF THE SHORT TERM PERIOD. LONG TERM... ZONAL UPPER LEVEL FLOW TUESDAY WILL AID MIXING OF THE DRYLINE EWD TO NEAR THE ERN BORDER OF THE FCST AREA WITH POTENTIAL FOR ISOLATED TSRA DEVELOPING NEAR IT LATE AFTN AND EARLY EVENING WITH PREVIOUS FCST SLIGHT CHC POPS LOOKING FINE. WILL THEN SEE UPPER LEVEL VEER TO THE NW AS A RIDGE BUILDS OVER THE WRN CONUS. MODELS CONTINUE TO PROG A SHORT WAVE TROUGH MOVING THROUGH THE NWLY FLOW FROM THE CTNL HIGH PLAINS WEDNESDAY TOWARD ARKANSAS BY THURSDAY MORNING. IT STILL APPEARS THAT THIS TROUGH COULD BRING SOME PRECIP INTO THE NERN ZONES WEDNESDAY NIGHT...WITH SOME LOW LEVEL LIFT FROM A COLD FRONT MOVING THROUGH THE FCST AREA IN THE WAKE OF THE UPPER LOW. MODELS CONTINUE TO STRUGGLE WITH THE STRENGTH OF THE COLD FRONT... THE ONSET OF RETURN FLOW...AND THE AMOUNT OF LOW LEVEL MOISTURE AVAILABLE TO ANY STORMS THAT DEVELOP ON THE HIGH TERRAIN TO THE NW OF THE FCST AREA. 00Z RUN HAVE TRENDED TOWARD A COOLER AND DRIER SOLUTION WITH NW FLOW PRECIP NOT IN THE MODELS UNTIL FRIDAY OR SATURDAY NIGHT. WILL RUN NEAR MOS POPS AND TEMPS IN THE THURSDAY THROUGH SUNDAY PERIOD. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 87 55 93 57 89 / 10 10 10 10 10 TULIA 90 59 92 61 89 / 10 10 10 10 10 PLAINVIEW 92 62 95 63 92 / 10 20 10 10 10 LEVELLAND 93 59 97 64 95 / 10 10 10 10 10 LUBBOCK 93 63 98 64 96 / 20 20 10 10 10 DENVER CITY 94 61 96 64 95 / 20 10 10 10 10 BROWNFIELD 94 61 98 64 96 / 20 20 10 10 10 CHILDRESS 94 67 97 68 94 / 20 20 20 20 10 SPUR 95 66 97 67 96 / 30 30 10 10 10 ASPERMONT 97 69 99 70 98 / 30 30 20 20 10 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
639 AM CDT MON MAY 28 2012 .SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT 304 AM CDT MON MAY 28 2012 MAIN FORECAST CONCERN IS ON CONVECTION CHANCES TODAY AND ANY POSSIBLE SEVERE WEATHER. CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED AN UPPER LOW OVER NORTHEAST MONTANA INSIDE UPPER TROUGHING COVERING THE HIGH PLAINS INTO WESTERN MINNESOTA...WHILE RIDGING WAS PRESENT IN THE GREAT LAKES REGION. THE COMBINATION OF HEIGHT FALLS AHEAD OF THE UPPER TROUGH...CONVERGENCE ALONG A SURFACE COLD FRONT...AND A STREAM OF INSTABILITY ALONG THE FRONT HELPED DEVELOP A LARGE EXPANSE OF SHOWERS AND THUNDERSTORMS FROM NORTHEAST MINNESOTA SOUTHWEST INTO EASTERN NEBRASKA LAST EVENING. A LOT OF THIS PRECIPITATION HAS DIMINISHED IN THE PAST FEW HOURS IN RESPONSE TO DIMINISHING INSTABILITY. THE INSTABILITY LOSS IS A COMBINATION OF NOCTURNAL COOLING AND DRY ADVECTION ON SOUTH WINDS...NOTED BY DEWPOINTS IN THE 50S OVER IOWA. NOTE THAT DEWPOINTS IN THE LOW 60S EXIST...BUT THIS IS MOSTLY UNDER THE PRECIPITATION. SURFACE COLD FRONT IS POSITIONED FROM NEAR DULUTH MN...TO ALBERT LEA MN AND SOUTHWEST INTO NORTHEAST KS. PLENTY OF WARM AIR REMAINS AHEAD OF THE FRONT WITH SURFACE TEMPERATURES STILL IN THE 70S OVER MUCH OF THE FORECAST AREA. 850MB TEMPS FROM 00Z SOUNDINGS WERE AROUND 20C. BEHIND THE COLD FRONT...850MB TEMPS DROP OFF TO 13C AT ABR...8C AT BIS AND 2C AT GGW. CLOUDS CLEAR OUT AS WELL DUE TO SUBSIDENCE AND DRY AIR...NOTED ON WATER VAPOR AS WELL WITH A DRY SLOT IN PLACE. TODAY... UPPER TROUGHING OVER THE NORTHERN PLAINS INTO WESTERN MINNESOTA IS PROGGED BY ALL MODELS TO SLIDE EAST...GIVING THE COLD FRONT A PUSH EASTWARD. ONGOING SHOWERS AND EMBEDDED THUNDERSTORMS ALONG/AHEAD OF THE FRONT SHOULD BECOME ISOLATED/SCATTERED IN NATURE AS THEY CROSS THE FORECAST AREA THIS MORNING...DUE TO DIMINISHING INSTABILITY AND FORCING. THE QUESTIONS THEN FOR THE AFTERNOON ARE: 1. HOW MUCH INSTABILITY BUILDS ALONG THE FRONT - PLUME OF LOWER 60S DEWPOINTS OBSERVED ALONG THE FRONT UNDER THE PRECIPITATION IS LIKELY TO STILL EXIST RIGHT INTO THE AFTERNOON. ENVISION THAT PRECIPITATION AND CLOUDS WILL BREAK UP IN THIS AREA OF HIGHER DEWPOINTS...ENOUGH THAT MIXING TO THE 850MB TEMPS OF 14-16C PROGGED AT 18Z WOULD BRING TEMPERATURES UP INTO THE LOW TO MID 80S. THIS RESULTS IN MLCAPE VALUES OF 1000-1500 J/KG ALONG THE FRONT WITH MLCIN DOWN NEAR 0 J/KG. 2. DOES CONVECTIVE INITIATION OCCUR - 0-2KM CONVERGENCE ON THE FRONT IS PRESENT...WEAK...BUT LIKELY ENOUGH GIVEN THE LACK OF MLCIN TO INITIATE CONVECTION. IN FACT...IT IS HARD TO FIND A MODEL THAT DOES NOT INITIATE ON THE FRONT. 3. WHERE IS THE FRONT AT INITIATION - THERE REMAINS TIMING DIFFERENCES. FOR EXAMPLE...THE 28.00Z NAM DOES NOT INITIATE UNTIL THE FRONT IS EAST OF THE AREA (APPROX 21Z)...THOUGH AT 18Z THE ENVIRONMENT IS FAVORABLE FOR INITIATION OVER THE SOUTHEAST END OF THE FORECAST AREA. THE 28.00Z ECMWF/GEM REGIONAL AND HIRES-ARW MODELS ARE SIMILAR TO THE NAM. THE 28.00Z GFS AND SPC WRF-NMM MODELS INITIATE IN THE SOUTHEAST END OF THE FORECAST AREA. KEPT A 50 PERCENT CHANCE IN THE SOUTHEAST END...TAPERING TO 20 PERCENT NEAR LA CROSSE. REGARDING SEVERE WEATHER...0-6KM SHEAR IS 40-50 KT ALONG/AHEAD OF THE FRONT...PLENTY FOR STORM ORGANIZATION. FRONTAL CONVERGENCE AND MLCIN LENDS CONVECTION TO LIKELY FORM A SQUALL LINE...BUT INITIAL CELLS COULD BE SUPERCELLULAR. SOUTHWEST FLOW AND 5-10 KTS OF 0-1KM SHEAR WOULD TEND TO RULE OUT TORNADO THREAT. DRY SLOT COMING IN OVER THE FRONT WILL HELP TO INCREASE DCAPE UP TO 1000-1200 J/KG OR SO...THEREFORE...DEFINITELY HAVE TO WATCH FOR WIND DAMAGE. CANNOT RULE OUT SOME HAIL TOO GIVEN LOWERING WET-BULB ZERO HEIGHTS FROM THE DRY AIR. IN THE WAKE OF THE COLD FRONT...BREEZY WEST WINDS SHOULD DEVELOP WITH CLEARING SKIES. SHOULD BE STILL WARM WEST OF THE FRONT AS THE 850MB TEMP FALL DOES NOT OCCUR UNTIL AFTER 00Z. TONIGHT AND TUESDAY... MODELS TAKE THE UPPER LOW WITHIN THE UPPER TROUGH NORTHEAST INTO NORTHERN ONTARIO ON TUESDAY. ALTHOUGH THE UPPER LOW IS LIFTING AWAY FROM THE AREA...500MB HEIGHTS WILL FALL OVER THE AREA... USHERING IN THE BEGINNING OF A COOL PERIOD. THERE IS ALSO A SHORTWAVE INDICATED TO COME ACROSS NORTHERN WISCONSIN TUESDAY AFTERNOON...ON THE SOUTH SIDE OF THE LOW...WHICH COMBINED WITH DAYTIME HEATING SHOULD PRODUCE SOME ISOLATED SHOWERS ALONG/NORTH OF I-94. GETTING BACK TO TONIGHT...SOMETHING INTERESTING IN MODELS IS A SHORTWAVE AHEAD OF THE UPPER LOW IN CENTRAL MINNESOTA AT 00Z. IT APPEARS SOME SHOWERS AND THUNDERSTORMS SHOULD FIRE UNDER THIS SHORTWAVE. AS THE SHORTWAVE HEADS NORTHEAST...A FEW OF THESE STORMS COULD IMPACT TAYLOR AND CLARK COUNTIES IN THE EVENING...AS SUGGESTED BY THE 28.00Z SPC WRF-NMM...NAM AND GEM REGIONAL MODELS. ADDED A 20-30 PERCENT CHANCE IN THIS AREA. OTHERWISE...THE REST OF THE FORECAST AREA SHOULD BE DRY...WITH BREEZY CONDITIONS LIKELY ON TUESDAY WITH DECENT MIXING AND A RELATIVELY TIGHT PRESSURE GRADIENT IN PLACE. A BLEND OF GUIDANCE SEEMS REASONABLE FOR BOTH LOWS AND HIGHS. TEMPS COULD FALL LATE TUESDAY AS NORTHWEST WINDS DRIVE COOLER 850MB AIR INTO THE AREA (TEMPS DOWN TO 4-6C AT 00Z) TUESDAY NIGHT THROUGH WEDNESDAY NIGHT... UPPER TROUGHING IS FORECAST TO PERSIST OVER THE WESTERN GREAT LAKES THROUGH AT LEAST WEDNESDAY...WHICH ALLOWS CANADIAN HIGH PRESSURE TO BUILD INTO THE FORECAST AREA. AS TO BE EXPECTED...THE 850MB TEMPS CONTINUE TO COOL...DROPPING TO 2-4C BY 18Z WEDNESDAY OR 1.5-2 STANDARD DEVIATIONS BELOW NORMAL. THIS COOLER AIR SHOULD ALLOW TEMPS TO EASILY DROP INTO THE 40S TUESDAY NIGHT...PERHAPS UPPER 30S AT THE TYPICAL COLD SPOTS. IN ADDITION...MIXING AT MOST WOULD ONLY ALLOW FOR HIGHS IN THE LOW 60S ON WEDNESDAY. NOTE... THIS IS STILL FAR FROM THE RECORD COLD HIGH OF 49 AT LA CROSSE SET IN 1897. DRY WEATHER SHOULD DOMINATE THROUGH WEDNESDAY...THOUGH CLOUDS DO LOOK TO BE ON THE INCREASE LATE IN THE DAY. THESE CLOUDS ARE ASSOCIATED WITH A MID LEVEL FRONTOGENESIS ZONE...DOWNSTREAM OF A POTENT SHORTWAVE TROUGH PROGGED TO DROP DOWN INTO THE BLACK HILLS AREA OF SOUTH DAKOTA LATE WEDNESDAY. A LARGE EXPANSE OF SHOWERS COULD BE GOING ON OVER THE DAKOTAS INTO NEBRASKA TOO AHEAD OF THIS SHORTWAVE. SOME OF THESE SHOWERS MAY PUSH INTO THE AREA WEDNESDAY NIGHT. THIS ALL DEPENDS IF THE SHORTWAVE PUSHES EAST TOWARDS MINNESOTA LIKE THE 28.00Z NAM/ECMWF. SHOULD THE 28.00Z GFS/UKMET/CANADIAN VERIFY...WITH THE SHORTWAVE CONTINUING TO DIG MORE SOUTH...WEDNESDAY NIGHT COULD BE DRY. FOR NOW...STUCK WITH A BLEND APPROACH WHICH RESULTS IN 20-40 PERCENT CHANCES SOUTH AND WEST OF I-94. NEITHER SITUATION OF THE SHORTWAVE TRACK PRODUCES ANY CAPE...AND IF ANYTHING THE SCENARIO LOOKS MORE WINTER-LIKE. THEREFORE...PULLED THUNDER MENTION. WEDNESDAY NIGHT ALSO LOOKS COOL...BUT NOT AS COOL AS TUESDAY NIGHT DUE TO MORE CLOUDS. .LONG TERM...THURSDAY THROUGH SUNDAY NIGHT 304 AM CDT MON MAY 28 2012 OVERALL...THE 28.00Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES ARE IN AGREEMENT ON THE UPPER LEVEL PATTERN IN THE MEAN. THE MODELS ALL SUGGEST UPPER TROUGHING OVER THE AREA THROUGH AT LEAST SATURDAY... THEN SHIFTING SLOWLY TO THE EAST AS RIDGING BUILDS INTO THE PLAINS. HOWEVER...THERE ARE SOME IMPORTANT DETAILS FOR THURSDAY INTO SATURDAY WHICH CONNECT BACK TO WEDNESDAY NIGHT. THAT POTENT SHORTWAVE WHICH WAS DROPPING INTO SOUTH DAKOTA ON WEDNESDAY...IF IT CONTINUES TO DIG LIKE THE 28.00Z GFS/UKMET/CANADIAN SHOW...WE COULD END UP WITH A REALLY CHILLY PERIOD. THESE MODELS ALL WRAP UP A FAIRLY STRONG SURFACE LOW TO THE SOUTHEAST OF THE AREA. THE CANADIAN IS THE COLDEST OF THEM ALL...WITH A RAINY FRIDAY AND HIGHS ONLY IN THE UPPER 40S. THIS IS THE OUTLIER...BUT DEFINITELY GOES TO SHOW WHAT COULD HAPPEN WITH THAT POTENT SHORTWAVE. ON THE OTHER HAND...THE ECMWF CONTINUES TO INDICATE A MORE PROGRESSIVE IDEA...WHICH OUTSIDE OF A COOL AND POSSIBLY WET THURSDAY...ALLOWS FOR TEMPERATURES TO REBOUND AND CONDITIONS TO DRY OUT. SINCE THE GFS ENSEMBLES ARE SPLIT WITH BOTH IDEAS PLAUSIBLE...HAVE WENT WITH A CONSENSUS BLEND FOR MUCH OF THE LONG TERM FORECAST. LOOKS LIKE FOR THE END OF THE WEEKEND TEMPERATURES WILL WARM BACK TOWARDS NORMAL AS 500MB HEIGHTS RISE. COULD SEE SOME WARM ADVECTION SHOWERS/STORMS TOO SATURDAY NIGHT THROUGH SUNDAY NIGHT...THOUGH LIMITED MOISTURE AVAILABILITY SHOULD LIMIT THE STRENGTH AND COVERAGE OF THE STORMS. && .AVIATION...TODAY AND TONIGHT 639 AM CDT MON MAY 28 2012 A COLD FRONT WILL MOVE ACROSS THE REGION TODAY BRINGING CHANCES FOR SHOWERS AND THUNDERSTORMS TO PARTS OF THE AREA. SHOWERS AND VICINITY THUNDERSTORMS WILL IMPACT KLSE IN THE 12-13Z TIMEFRAME. CLOUD BASES ARE EXPECTED TO LOWER TO INTO THE 4-5 KFT RANGE AS THE SHOWERS MOVE THROUGH. VISIBILITIES COULD BE REDUCED TO AROUND 6 SM. THE COLD FRONT SHOULD PASS KRST DRY...WITH THE MAIN IMPACT BEING A SHIFT TO WEST WINDS AND INCREASING TO AROUND 16 KTS BY 20Z WITH GUSTS TO AROUND 25 KTS POSSIBLE. THE FRONT IS EXPECTED TO TRIGGER SHOWERS AND THUNDERSTORMS THIS AFTERNOON ACROSS SOUTHERN AND CENTRAL WISCONSIN. THERE IS UNCERTAINTY REGARDING EXACTLY WHERE THE STORMS WILL FIRE ALONG THE FRONT THIS AFTERNOON. CURRENT THINKING IS THAT THIS COULD OCCUR JUST EAST OF KLSE SO HAVE DECIDED TO MAINTAIN VICINITY THUNDERSTORMS AND SCT050 CB AT KLSE FROM 21Z THROUGH 00Z. IF THE STORMS IMPACT KLSE THEY WOULD BE CAPABLE OF PRODUCING GUSTY WINDS AND POSSIBLY LARGE HAIL. WINDS WILL SHIFT TO THE WEST AT KLSE BEHIND THE FRONT AROUND 21 Z. PLAN ON SUSTAINED WIND SPEEDS AROUND 12 KTS WITH GUSTS AROUND 20 KTS POSSIBLE. CLOUDS WILL QUICKLY DECREASE BEHIND THE FRONT WITH MOSTLY CLEAR SKIES AND GOOD VFR CONDITIONS BY LATE AFTERNOON THROUGH THE OVERNIGHT HOURS. && .HYDROLOGY... 459 AM CDT MON MAY 28 2012 RECENT HEAVY RAINS AT THE UPPER END OF THE MISSISSIPPI RIVER BASIN... IN PARTICULAR ACROSS THE MINNEAPOLIS AREA AND ALONG THE MINNESOTA RIVER WHICH DRAINS INTO THE MISSISSIPPI...WILL RESULT IN THE MISSISSIPPI RIVER RISING IN OUR FORECAST AREA. CURRENTLY...ONLY WABASHA IS FORECAST TO EXCEED FLOOD STAGE DURING THE WEEKEND. HOWEVER...MANY OTHER LOCATIONS UP AND DOWN THE MISSISSIPPI RIVER COULD APPROACH FLOOD STAGE. SEE THE LATEST ESF AND RVS STATEMENTS FOR MORE DETAILS ON THE FORECASTS. IF CONFIDENCE INCREASES THAT WABASHA WILL EXCEED FLOOD STAGE...FLOOD WATCHES AND/OR WARNINGS MAY BE ISSUED. LOOKING AHEAD AT PRECIPITATION FOR THIS WEEK...FOR THE MOST PART ONLY A FEW PERIODS OF LIGHT PRECIPITATION ARE EXPECTED...LIKELY TO HAVE LITTLE EFFECT ON THE MISSISSIPPI. HOWEVER...THE 28.00Z CANADIAN MODEL SUGGESTS POTENTIAL FOR MODERATE TO HEAVY RAINFALL COME THURSDAY AND THURSDAY NIGHT. RIGHT NOW THIS MODEL IS CONSIDERED AN OUTLIER. && .ARX WATCHES/WARNINGS/ADVISORIES... 304 AM CDT MON MAY 28 2012 WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...WETENKAMP HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
210 PM PDT MON MAY 28 2012 .SYNOPSIS... CONTINUED INLAND WARMING AND WEAKER WINDS TODAY UNDER HIGH PRESSURE. FOR TUESDAY AND WEDNESDAY...A WEAK TROUGH OF LOW PRESSURE WILL BRING STRONGER ONSHORE FLOW WITH GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS. WARMER INLAND WITH WEAKER WINDS FOR THURSDAY AND FRIDAY UNDER HIGH PRESSURE. FOR SATURDAY THROUGH MONDAY...A TROUGH OF LOW PRESSURE TO THE NORTH WILL BRING INCREASING ONSHORE FLOW WITH SLOW COOLING...SLOW DEEPENING OF THE MARINE LAYER WITH MORE COASTAL LOW CLOUDS AND FOG...AND GUSTY WEST WINDS IN THE MOUNTAINS AND DESERTS. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... SO FAR TODAY TEMPERATURES ARE UP 2 TO 6 DEGREES OVER YESTERDAY...REFLECTING ABOUT HALF THE 24 HOUR WARMING SHOWN IN THE MORNING SOUNDINGS...BUT WE STILL HAVE A FEW MORE HOURS OF HEATING TO GO. WITH THIS IN MIND...THE HIGHS FORECAST FOR TODAY APPEAR TO BE CLOSE TO WHAT WILL BE OBSERVED. THE PRESSURE GRADIENTS ARE RUNNING SLIGHTLY LOWER THAN YESTERDAY AND THIS ALSO AGREES WITH THE MODEL TREND AND FORECAST NUMBERS. BLENDED WIND AND WIND GUSTS HALFWAY TOWARDS THE LATEST HRRR AND 12Z WRF MODELS. THE 28/12Z GFS AND GEM MODELS WERE IN LINE WITH PREVIOUS RUNS AND OTHER REGIONAL MODELS. THE AVERAGE 1000-500 MB THICKNESS VALUES OF ALL MODELS INCREASE 20 METERS ON TUESDAY...50 METERS ON WEDNESDAY AND THURSDAY...THEN BEGIN TO FALL 10-20 METERS EACH DAY FROM FRIDAY INTO NEXT TUESDAY. MADE APPROPRIATE ADJUSTMENTS TO MAX AND MIN TEMP GRIDS TO REFLECT THESE CHANGES. THE MARINE LAYER DEPTH...AS DEFINED BY SIGNIFICANT DEWPOINT GRADIENT...FORECAST TO BE AROUND 2100 FEET THROUGH WEDNESDAY...LOWER TEMPORARILY WEDNESDAY NIGHT/THURSDAY TO AROUND 1500 FEET AS RIDGE REBUILDS/SUBSIDENCE LOWERS INVERSION FOLLOWING PASSAGE OF SHORT WAVE TROUGH...THEN STEADILY INCREASE TO AROUND 3500 FEET BY SATURDAY NIGHT/SUNDAY. DI ADD SOME DENSE FOG OVER THE NEXT 3 NIGHTS GENERALLY COASTAL MESAS AND LOWER INLAND VALLEYS. && FROM MORNING DISCUSSION.... THE 28/12Z NAM IS IN AGREEMENT WITH OTHER MODELS EARLIER RUNS...28/06Z GFS AND 28/00Z ECMWF...ON TRENDS IN 1000-500 MB THICKNESS AND PRESSURE GRADIENTS AND PLACEMENT OF SYNOPTIC FEATURES. THOUGH THERE ARE DIFFERENCES IN MAGNITUDES OF THESE VARIABLES GENERALLY LOOKING FOR WARMING TEMPERATURES THROUGH FRIDAY AND INCREASING ONSHORE FLOW AS HIGH PRESSURE BUILDS ALOFT AND SURFACE THERMAL TROUGH DEEPENS OVER THE CA/AZ/NV BORDER REGION. THE NAM INDICATES A WEAK COASTAL EDDY WILL BE PRESENT DURING THE NIGHT AND MORNING HOURS. THERE ARE PERIODS OF POSITIVE VORTICITY ADVECTION/ WEAK CYCLONIC FLOW AT 500 MB THAT WOULD SUPPORT THIS THROUGH TUESDAY. THE SHORT WAVE TROUGH/QUASI-CUTOFF 500 LOW SHOWN AT 500 MB LEVEL THAT MOVES OVER THE REGION WEDNESDAY SEEMS TO HAVE NO SURFACE REFLECTION. LOOKING FURTHER OUT THE 28/06Z GFS AND THE 28/00Z ECWMF WERE BOTH HINTING AT CHANCE OF PRECIPITATION FOR FRIDAY NIGHT/SATURDAY MORNING...LIGHT RAIN OR DRIZZLE COASTAL SLOPES...AND A GENERAL COOL DOWN INTO NEXT TUESDAY. WILL REEVALUATE THIS WHEN THE28/12Z GFS MODEL IS RECEIVED...BUT PROBABLY NOT GOING TO MAKE ADDITIONAL CHANGES TO CURRENT GRIDS/FORECAST. && .AVIATION... 282030Z...CLEAR AND VFR CONDITIONS WILL PREVAIL EVERYWHERE THROUGH EARLY EVENING. BETWEEN 05-10Z THE LOW CLOUDS WILL RETURN TO COASTAL AIRPORTS WITH BASES 800-1000 FEET ASL AND LOCAL VIS 5SM BR ON THE MESAS. SCATTER OUT WILL OCCUR BY 16-17Z TUESDAY. && .FIRE WEATHER... TEMPS UP ABOUT 2 TO 5 DEGREES EACH DAY THROUGH THURSDAY. ONSHORE PRESSURE GRADIENTS FORECAST TO BE ABOUT 2 MB STRONGER TUESDAY...SO LOOK FOR WIND GUSTS ABOUT ONE AND THIRD TIMES AS STRONG AS TODAY. TREND FOR WEDNESDAY IS TO DROP BACK TO TODAYS NUMBERS...THEN BACK UP AGAIN ON THURSDAY AND FRIDAY. GENERAL COOL DOWN AND MOISTENING FROM FRIDAY ON. MIGHT SEE SOME DRIZZLE OR LIGHT RAIN FRIDAY NIGHT INTO SUNDAY MORNING LOWER COASTAL SLOPES WESTWARD BUT NO WETTING RAIN IN THE FORECAST. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC/FIRE WEATHER...BALFOUR AVIATION/MARINE...MM
AREA FORECAST DISCUSSION
NWS NEW YORK NY
204 PM EDT MON MAY 28 2012 .SYNOPSIS... A NEARLY STATIONARY FRONT OVER THE NORTHEAST WILL RESULT IN PERIODS OF STORMY WEATHER THROUGH TUESDAY. A COLD FRONT MOVES THROUGH WEDNESDAY. HIGH PRESSURE BUILDS TOWARD THE AREA WEDNESDAY NIGHT AND THURSDAY...THEN MOVES EAST OF THE REGION FRIDAY AS A FRONTAL SYSTEM APPROACHES FROM THE SOUTHWEST. THE FRONTAL SYSTEM WILL IMPACT THE REGION LATE FRIDAY THROUGH THE UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST RADAR AND VIS SAT IMAGES SHOW THE DISSIPATING MCS OVER CENTRAL NY STILL PUSHING ESE. DESPITE THE CURRENT DISSIPATION...FURTHER DEVELOPMENT IS EXPECTED LATE THIS AFTERNOON AND INTO THIS EVENING...ESPECIALLY OVER HUDSON RIVER VALLEY AND CONNECTICUT. A WARM FRONT REMAINS POSITIONED ACROSS CENTRAL NEW ENGLAND INTO WESTERN NY...KEEPING THE WAA PERSISTENT OVER THE CWA. AN UPPER LEVEL SHORTWAVE CONTINUES TO PROGRESS DOWN THE RIGHT SIDE OF THE UPPER LEVEL RIDGE...CREATING DECENT LIFT THROUGH THE NEW ENGLAND AREA THIS AFTERNOON. THE CLEARING OF THE SKIES ALONG WITH THE WAA ARE PUSHING TEMPS INTO THE MID TO UPPER 80S AND DEWS PTS NEARING 70. LATEST RAP SOUNDINGS INDICATE INSTABILITY READINGS HAVE PUSHED WELL ABOVE 1000 J/KG AND LAPSE RATES ARE STEEPENING QUICKLY...PUSHING ABOVE 7 C/KM ALREADY. DESPITE WEAKER SHEAR VALUES LESS THAN 30 KTS...CONDITIONS ARE IN PLACE FOR STRONG TO SVR STORM DEVELOPMENT...WITH THE RIGHT TRIGGER. ONE MORE THING TO NOTE IS THE DEVELOPING SEA BREEZE ALONG SOUTHERN LI AND CT PUSHING INLAND. BEHIND THE SEA BREEZE...A MORE STABLE AND COOLER ENVIRONMENT IS EXPECTED...WHICH WILL HELP IN DIMINISHING THE CHANCES FOR TSTORM DEVELOPMENT RIGHT ALONG THE COASTS. MESOSCALE MODELS ARE STILL HAVING A HARD TIME GETTING A READ FOR THE CONVECTION THIS AFTN...HAVING NOT CAPTURED THE CURRENT ACTIVITY. WILL REMAIN WITH THE IDEA THE BEST THREAT IS INLAND NY AND CT FOR DAMAGING WINDS...AND HAIL. EHI VALUES NEAR 3 M2/S2 HINT AT SOME POSSIBLE ROTATION WHICH MAY LEAD TO TOR FORMATION. BUT THIS THREAT LOOKS TO REMAIN NORTH OF OUR CWA. THERE IS A MODERATE RISK OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... PREVAILING NW STORM FLOW TAKES ANY TSTMS THRU THE CWA TNGT. THE ATMOSPHERE THEN RECHARGES FOR TUE AS A COLD FRONT APPROACHES. FALLING HEIGHTS WILL PROVIDE SYNOPTIC SUPPORT...SO POPS RAMP UP TO LIKELY BY LATE AFTN. THERE WILL REMAIN A SVR THREAT...BUT LLVL HELICITY WILL BE MUCH LWR WITH THE WARM FRONT OUT OF THE PICTURE. TEMPS THRU THE FCST ARE BLEND OF THE MAV/MET...WHICH ARE SUPPORTED BY THE NAM 2M DATA. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODEL AGREEMENT AND CONSISTENCY REMAINS WITH THE GFS AND ECMWF FOR TUESDAY NIGHT AND WEDNESDAY WITH THE PASSAGE OF THE COLD FRONT WEDNESDAY. TIMING DIFFERENCES EMERGE FRIDAY INTO THE WEEKEND WITH THE TIMING OF THE FRONTAL SYSTEM IMPACTING THE REGION. THE GFS IS SLOWER THAN THE ECMWF.PREFER A LITTLE SLOWER MOVEMENT WITH THE GFS AS LOW IS ALMOST CUT OFF...THEN GETS PICKED UP WITH THE NORTHERN STREAM SATURDAY NIGHT INTO SUNDAY. WITH THE SLOWER MOVEMENT WILL HAVE WET WEATHER INTO SUNDAY. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... WARM FRONT WILL REMAIN NEARLY STATIONARY OVER CENTRAL AND SOUTHERN NEW ENGLAND TODAY. AT THE SAME TIME...A TROUGH OF LOW PRESSURE REMAINS OVER OR JUST EAST OF THE CITY TERMINALS. SEA BREEZE HAS MADE IT THROUGH KBDR AND KISP...AND POSSIBLY JUST RECENTLY AT KHPN. SEA BREEZE PROBABLE FOR KJFK AND KGON SOON. LESS CONFIDENCE THAT IT REACHES KLGA...BUT STILL IN THE FORECAST. SCATTERED THUNDERSTORMS POSSIBLE AS EARLY AS 19-20Z NEAR KSWF...AND AS EARLY AS 21-22Z AT THE CITY TERMINALS. ELSEWHERE...RANGING FROM AS EARLY AS 20-22Z. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: SEA BREEZE TIMING COULD BE OFF BY AROUND 2 HOURS...AND POSSIBLY MIGHT NOT OCCUR AT ALL THIS AFTERNOON. THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 22Z. KLGA FCSTER COMMENTS: SEA BREEZE TIMING COULD BE OFF BY AROUND 2 HOURS...AND POSSIBLY MIGHT NOT OCCUR AT ALL THIS AFTERNOON. WINDS OTHERWISE MOST LIKELY TO BE NE TO N UNTIL AROUND 21Z...BUT UNDER 8KT. THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 22Z. KEWR FCSTER COMMENTS: THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 21Z. SLIGHT CHANCE THAT SEA BREEZE REACHES SOMETIME AFTER 20Z. WINDS WOULD THEN SHIFT NEAR 150 DEGREES TRUE. KTEB FCSTER COMMENTS: THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 21Z. KHPN FCSTER COMMENTS: THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 20Z. KISP FCSTER COMMENTS: ISOLATED THUNDERSTORM IN THE VICINITY POSSIBLE AS EARLY AS AROUND 23Z. .OUTLOOK FOR 18Z TUE THROUGH SAT... .TUE-TUE NIGHT...TSTMS LIKELY AFTERNOON INTO THE OVERNIGHT WITH A COLD FRONT. .WED...IMPROVEMENT TO VFR. .WED NIGHT-FRI MORNING...VFR. .FRI AFTERNOON-SAT...MVFR OR LOWER POSSIBLE IN SHOWERS/TSTMS. && .MARINE... FORECAST ON TRACK. WITH THE WARM FRONT N OF THE WATERS...PERSISTENT S/SW FLOW WILL BUILD SEAS ON THE OCEAN THRU TUE. WAVEWATCH RUNNING SLIGHTLY HIGH...SO THE DATA HAS BEEN ADJUSTED DOWNWARD BY AROUND A FT THRU THE PERIOD. BEST CHANCE FOR THE 5 FT SEAS WILL BE DURING THE DAY TUE. THERE IS A LOW PROBABILITY THAT SEAS COULD BUILD TO 5 FT LATE TNGT. A CONTINUING SOUTH TO SOUTHWEST FLOW TUESDAY NIGHT INTO WEDNESDAY...AHEAD OF A COLD FRONT...WILL LIKELY KEEP SEAS ON THE OCEAN WATERS AT OR ABOVE 5 FT. HOWEVER...WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT LEVELS. WINDS SHIFT TO THE WEST TO NORTHWEST LATE WEDNESDAY INTO THURSDAY...BEHIND THE COLD FRONT...WITH SUBSIDING SEAS BELOW 5 FT. HIGH PRESSURE BUILDS EAST OF THE WATERS FRIDAY AS A FRONTAL SYSTEM APPROACHES FROM THE SOUTHWEST. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT LEVELS FRIDAY. && .HYDROLOGY... ANY TSTMS THAT DEVELOP THRU TUE WILL BE CAPABLE OF PRODUCING HEAVY RAIN. RAINFALL RATES MAY EXCEED 1 INCH/HR AT TIMES IN THE STRONGEST ACTIVITY. SOME MINOR URBAN AND POOR DRAINAGE FLOODING CAN BE EXPECTED THRU THE PERIOD. IN ADDITION...THERE IS THE THREAT FOR ISOLD FLASH FLOODING. AROUND A HALF INCH OF RAINFALL IS LIKELY TUESDAY NIGHT INTO WEDNESDAY WITH LOCAL 1 TO 2 INCH AMOUNTS IN HEAVIER SHOWERS AND THUNDERSTORMS. DRY WEATHER RETURNS LATE WEDNESDAY THROUGH THURSDAY. NUISANCE FLOODING IS POSSIBLE TUESDAY NIGHT AND WEDNESDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MET/12 NEAR TERM...SEARS/12 SHORT TERM...12 LONG TERM...MET AVIATION...JC MARINE...MET/12 HYDROLOGY...MET/12
AREA FORECAST DISCUSSION
NWS ALBANY NY
139 PM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LOOKING AT 18Z SPECIAL BALLOON SOUNDING. A WARM FRONT MEANDERS FROM THE GREAT LAKES EASTWARD ACROSS THE SOUTHERN PORTION OF OUR FORECAST AREA AND SOUTHERN NEW ENGLAND. REMNANT OF MCS RIDING ALONG FRONTAL BOUNDARY. ACTIVITY HAS BEEN WEAKENING TO THE NORTH OF THE BOUNDARY IN THE ELEVATED INSTABILITY. HOWEVER TO THE THE SOUTH OF THE BOUNDARY IN THE SURFACE BASED INSTABILITY CONVECTION HAS FIRED. HOWEVER THIS ACTIVITY HAS ALSO WEAKENED. BASED ON SPC MESOSCALE ANALYSIS SBCAPE HAS INCREASED TO 1500 TO 2000 J/KG ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA. DEW POINTS AT KPOU 70 DEGREES AND AT KALB 57 DEGREES. THE POSITION OF THE WARM FRONT HAS BEEN DIFFICULT TO FORECAST HOWEVER IT SHOULD FINALLY LIFT TO OUR NORTH AND EAST THIS EVENING AS ITS ASSOCIATED COLD FRONT APPROACHES. ALOFT THE UPPER RIDGE IS MODELED TO BUILD SLIGHTLY AND CREST OVER REGION THIS AFTERNOON. HEIGHTS WILL BEGIN TO FALL THIS EVENING AS THE RIDGE SHIFTS EASTWARD AND THE UPPER TROUGH APPROACHES. GUIDANCE INDICATES WEAK SHORT WAVES WILL RIDE OVER TOP THE RIDGE. WILL CONTINUE TO KEEP A CLOSE ON THE EYE RADAR AND TRENDS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE TH POTENTIAL TO BECOME SEVERE AS INSTABILITY ACROSS THE REGION INCREASES THROUGH THE DAY. AS OF 1000 AM EDT...CONTINUE TO FOLLOW AN MCS WORKING TOWARD OUR ADIRONDACKS...BUT WEAKENING. SPC GUIDANCE INDICATED ANY REAL SURFACE INSTABILITY WAS WELL SOUTH AND WEST OF THE CAPITAL REGION. HOWEVER...MID LEVEL LAPSE RATES WERE STEEP...UP TO 7C/KM...AS A EML MOVES OVER THE REGION LATER ON. DEWPOINTS WERE ONLY IN THE 50S FROM ALBANY NORTHWARD...BUT JUMP TO THE 60S FURTHER SOUTH AND EVEN EAST OF THE CAPITAL REGION (BERKSHIRES INCLUDED). UNFORTUNATELY MUCH OF THE MESO SCALE MODELS WERE NOT OF MUCH ASSISTANCE...FAILING TO INITIALIZE THE MCS. THE LATEST HRRR FINALLY HAS LOCKED ONTO IT. THE 12Z NAM HOWEVER...STILL DID NOT DEPICT THE FEATURE! SPC WRF DID APPEAR TO CAPTURE THE MCS BUT LOOKED A LITTLE SLOW AND NORTH WITH ITS PROGRESS. A WARM FRONT WAS PERCHED TO THE SOUTH OF THE CAPITAL REGION AND APPEARS TO BE IN NO HURRY TO LIFT NORTHWARD. IT LOOKS AS IF THE MOST ENERGETIC PORTION OF THE MCS WAS IN THE PROCESS OF LIFTING SOUTHWARD...WITH THE WEAKENING PORTION HEADING INTO OUR AREA WELL NORTH OF THE WARM FRONT. HAVE UPDATED GRIDS TO REFLECT THIS TREND AND WE BELIEVE THIS TREND WILL CONTINUE. HOWEVER...THE COLD POOL ASSOCIATED WITH THIS MCS AS WELL AS OUTFLOW BOUNDARY COULD BECOME FOCUS FOR CONVECTION LATER ON. THE WARM FRONT WILL BE THE SYNOPTIC FOCUS FOR ANY STORMS. SINCE IT LOOKS TO BE A LITTLE SLOWER THAN EARLIER THOUGHT...WE NOW BELIEVE THE GREATEST POTENTIAL FOR CONVECTIVE INITIATION MIGHT ACTUALLY BE THE CATSKILLS...MID HUDSON VALLEY..LITCHFIELD COUNTY INTO THE BERKSHIRES...BUT REALLY ANY AREA IS STILL FAIR GAME FOR DEVELOPMENT BY THIS AFTERNOON AS MIXED LAYER CAPES WILL LIKELY INCREASE TO OVER 1000 J/KG NORTH...AND 2000 J/KG SOUTH LATER THIS AFTERNOON. THE QUESTION WILL BE WHERE EXACTLY CONVECTION WILL DEVELOP. STAY TUNED. DID NOT TINKER WITH THE GRIDS FROM 18Z ON. AFTERNOON HIGHS LOOKED REASONABLE BASED ON WHAT WE HAVE SEEN (UNFORTUNATELY WITHOUT THE ASSISTANCE OF OUR RAOB WHICH IS STILL OTS). LOOKS FOR HIGH TEMPERATURES 85-90 VALLEY LOCATIONS FROM ALBANY SOUTHWARD...80-85 HIGHER TERRAIN. TO THE NORTH ALBANY...HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S VALLEY LOCATIONS...70S HIGHER TERRAIN. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... MORE WIDESPREAD AND ORGANIZED STORMS ARE EXPECTED TUESDAY INTO TUESDAY EVENING WITH THE THREAT FOR MORE SEVERE THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MORE WIDESPREAD AND ORGANIZED CONVECTION IS EXPECTED TUESDAY AND TUESDAY NIGHT AHEAD OF THE COLD FRONT WHICH IS EXPECTED TO CROSS THE FA LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AND THE UPPER TROUGH. FOR MUCH OF THE PERIOD FROM TUESDAY THROUGH TUESDAY NIGHT THE FA WILL BE IN THE WARM SECTOR WITH A VERY HUMID AIRMASS REMAINING IN PLACE AS DEWPOINTS REMAIN IN THE 60S TO NEAR 70 THROUGH TUESDAY EVENING. WHILE MID LEVEL LAPSES RATES LESSEN TO 6 TO 6.5 C/KM...MLCAPES REMAIN VERY HIGHS WITH UP TO 4000 J/KG POSSIBLE EARLY TUESDAY AFTERNOON AND INCREASING UPPER JET DYNAMICS AS UPPER JET ENDS UP PUTTING FA IN EQUATORWARD ENTRANCE REGION OF A CYCLONICALLY CURVED 100+ KT JET MAX OVER SRN ONTARIO. BOTH DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO BE POSSIBLE ESPECIALLY DURING THE AFTERNOON INTO THE EVENING HOURS ON TUESDAY. EXPECT HIGHS ON TUESDAY IN THE 80S WITH LOWS TUESDAY NIGHT IN THE MID 50S TO MID 60S. HAVE ADDED ENHANCED WORDING FOR THIS ENTIRE PERIOD TO THE ZONE FORECASTS AND GRIDS. THERE WILL STILL BE A CHANCE OF SHOWERS WEDNESDAY MORNING AFTER WHICH DRY WEATHER IS EXPECTED LATE WEDNESDAY INTO WEDNESDAY NIGHT WITH HIGH PRESSURE GRADUALLY BUILDING FROM THE GREAT LAKES INTO THE NORTHEAST. EXPECT HIGHS ON WEDNESDAY IN THE MID 70S TO LOWER 80S WITH LOWS WEDNESDAY NIGHT IN THE MID 40S TO MID 50S. && .LONG TERM /THURSDAY THROUGH SUNDAY/... USED HPC GUIDANCE STRICTLY (WITH SOME MINOR MODIFICATIONS). HIGH PRESSURE WILL START OUT THE PERIOD BRINGING TEMPERATURES SLIGHTLY COOLER THAN NORMALS FOR LATE MAY/EARLY JUNE. DAYTIME HIGHS WILL BE IN THE 70S...EXCEPT 60S NORTH. NIGHTTIME LOWS WILL BE IN THE 50S SOUTH...40S NORTH THURSDAY AND FRIDAY. THEN...THE IT LOOKS AS IF AN IMPRESSIVE MID LATITUDE LOW PRESSURE AREA WILL APPROACH THE REGION FROM THE SOUTHWEST LATE FRIDAY INTO FRIDAY NIGHT. THIS STORM MIGHT HAVE SOME TROPICAL MOISTURE ASSOCIATED WITH BERYL. EVEN IF IT DOESN/T...LOOKS LIKE A GOOD CHANCE IT WILL BRING A PRETTY GOOD SOAKING RAIN TO THE REGION FRIDAY INTO EARLY SATURDAY. AS LONG AS IT KEEPS MOVING...SOME MID LEVEL DRYING COULD TAKE PLACE LATE SATURDAY...HOWEVER LOW LEVEL MOISTURE WILL LIKELY REMAIN IN PLACE...SO RAIN TAPERS TO SCATTERED SHOWERS...BUT MIGHT NOT COMPLETELY END. CLOUDS LOOK TO HOLD IN PLACE...AND AS A RESULT HIGHS WILL BE MAINLY CONFINED TO THE 60S ON SATURDAY. A BREEZY SOMEWHAT COOL DAY FOR SUNDAY IN THE WAKE OF THE STORM...STILL WITH SOME RESIDUAL CLOUDS...MAINLY NORTH...AND PERHAPS SOME LIGHT RESIDUAL INSTABILITY INDUCED SHOWERS. FOR NOW...JUST CALL IT SLIGHT POPS. HIGH TEMPERATURES WILL BE IN THE 60S HIGHER TERRAIN...LOWER 70S MOST VALLEY AREAS. DRY WEATHER LOOKS TO RETURN MONDAY WITH ANOTHER CANADIAN HIGH PRESSURE BUILDING IN. HIGHS MAINLY IN THE 70S. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... MAINLY VFR CONDITIONS SHOULD PREVAIL AT ALL THE TAF SITES THROUGH THE AFTERNOON AND EARLY EVENING HOURS. THE THREAT OF CONVECTION IMPACTING ANY TAF IS STILL THERE...BUT CONFIDENCE FOR ANY GIVEN TIME IS LOW (UNDER 25 PERCENT). THEREFORE PLACED VCSH IN THE TAFS LATER THIS AFTERNOON...EXCEPT KPOU...WHERE A CLUSTER OF SHOWERS NOW IN THE CATSKILLS MIGHT PASS VERY CLOSE TO OR EVEN BRIEFLY IMPACT THAT TAF SITE. SO PLACED A TWO HOUR WINDOW OF VCSH FROM THE START OF THE TAF SITE. THEN...PLACE VCSH IN LATER THIS EVENING. LATER TONIGHT...THREW MVFR IN ALL SITES AFT 06Z DUE TO INCREASED CHANCES OF STRATUS AND OR BR DEVELOPING. THERE WILL STILL BE THE CHANCE OF CONVECTION BUT CONFIDENCE REMAINS TOO LOW TO EVEN PLACE A PROB30 IN THAT THIS TIME. EVEN INTO MONDAY...WILL CONTINUE THE VCSH IDEA AS THE THUNDERSTORM POTENTIAL CONTINUES. OTHERWISE LOOKS MAINLY VFR AT THIS VANTAGE POINT BUT CONFIDENCE IS ONLY MODERATE. THE WIND WILL BE OR BECOMING SOUTHERLY 10KTS OR LESS FOR THE REMAINDER OF TODAY. KPSF ACTUALLY HAD A GUSTY WEST WIND BUT THAT WIND SHOULD BACK TO THE SOUTH LATER ON. OVERNIGHT THE WIND WILL GENERALLY BE LIGHT OR SOUTH UNDER 10KTS. KEEP IN MIND...SHOULD ANY THUNDERSTORM IMPACT THE TAF SITES...THE WIND COULD BRIEFLY BE A BIT STRONGER. PLEASE REFER BACK OFTEN TO THIS PRODUCE FOR ANY POSSIBLE UPDATES AS WE CONTINUE TO MONITOR THE SITUATION. TUE...SUB-VFR. CIG. SHRA/TSRA LIKELY. WED...MVFR/IFR IMPROVING TO VFR. CHC SHRA/TSRA IN THE AM. THU...VFR...NO SIG WX. FRI...VFR. SLIGHT CHC SHOWERS IN AFTERNOON. SAT...SUB-VFR. CIG. GOOD CHANCE SHOWERS OR RAIN. && .FIRE WEATHER... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .HYDROLOGY... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. INCREASING LEVELS OF HUMIDITY ARE EXPECTED UNTIL THE PASSAGE OF THE COLD FRONT LATE TUESDAY NIGHT OR WEDNESDAY MORNING. IN ADDITION PWATS RISE TO BETWEEN 1.50 AND 1.75 INCHES WITH THE POTENTIAL FOR SOME TRAINING CELLS AND SOME BACKBUILDING CELLS. WHILE THE THREAT OF FLOODING IS NOT EXPECTED TO BE WIDESPREAD...ISOLATED TO SCATTERED AREAS MAY HAVE CONDITIONS SIMILAR TO THOSE WHICH OCCURRED SUNDAY EVENING ACROSS SOUTHEAST PORTIONS OF THE FA WHERE SEVERAL INCHES OF RAIN FELL IN A SHORT PERIOD OF TIME...IN THIS CASE IT WAS IN JUST OVER AND HOUR. THEREFORE FLASH FLOODING WOULD BE THE MAJOR CONCERN...BUT DUE TO THE EXPECTED ISOLATED TO SCATTERED NATURE OF OCCURRENCE DO NOT PLAN ON ISSUING A WATCH AT THIS TIME AND WILL HIGHLIGHT IN THE HWO. && .CLIMATE... NEAR RECORD TO RECORD HIGHS FORECAST FOR TODAY RECORD HIGH TEMPERATURES FOR MAY 28TH... ALBANY NY: 91 DEGREES SET BACK IN 1911 RECORDS DATE BACK TO 1820 GLENS FALLS: 88 DEGREES SET BACK IN 1998 (AND PREVIOUS YEARS) RECORDS DATE BACK TO 1944 POUGHKEEPSIE NY: 90 DEGREES SET BACK IN 1977 RECORDS DATE BACK TO 1949 FOR MORE GO TO OUR CLIMATE PAGE AT: WWW.NWS.NOAA.GOV/CLIMATE/LOCAL_DATA.PHP?WFO=ALY && .EQUIPMENT... NOW LOOKING AT AN 18Z SPECIAL BALLOON. THE ELECTRONICS STAFF HAS INSTALLED THE NEW SIGNAL PROCESSING SYSTEM. WE ARE GOING TO TRY A 17Z SPECIAL BALLOON LAUNCH. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/HWJIV/11 NEAR TERM...IAA/HWJIV/11 SHORT TERM...11 LONG TERM...KL AVIATION...HWJIV FIRE WEATHER...11 HYDROLOGY...11 CLIMATE... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
123 PM EDT MON MAY 28 2012 .SYNOPSIS... A NEARLY STATIONARY FRONT OVER THE NORTHEAST WILL RESULT IN PERIODS OF STORMY WEATHER THROUGH TUESDAY. A COLD FRONT MOVES THROUGH WEDNESDAY. HIGH PRESSURE BUILDS TOWARD THE AREA WEDNESDAY NIGHT AND THURSDAY...THEN MOVES EAST OF THE REGION FRIDAY AS A FRONTAL SYSTEM APPROACHES FROM THE SOUTHWEST. THE FRONTAL SYSTEM WILL IMPACT THE REGION LATE FRIDAY THROUGH THE UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST RADAR AND VIS SAT IMAGES SHOW THE DISSIPATING MCS OVER CENTRAL NY STILL PUSHING ESE. DESPITE THE CURRENT DISSIPATION...FURTHER DEVELOPMENT IS EXPECTED LATE THIS AFTERNOON AND INTO THIS EVENING...ESPECIALLY OVER HUDSON RIVER VALLEY AND CONNECTICUT. A WARM FRONT REMAINS POSITIONED ACROSS CENTRAL NEW ENGLAND INTO WESTERN NY...KEEPING THE WAA PERSISTENT OVER THE CWA. AN UPPER LEVEL SHORTWAVE CONTINUES TO PROGRESS DOWN THE RIGHT SIDE OF THE UPPER LEVEL RIDGE...CREATING DECENT LIFT THROUGH THE NEW ENGLAND AREA THIS AFTERNOON. THE CLEARING OF THE SKIES ALONG WITH THE WAA ARE PUSHING TEMPS INTO THE MID TO UPPER 80S AND DEWS PTS NEARING 70. LATEST RAP SOUNDINGS INDICATE INSTABILITY READINGS HAVE PUSHED WELL ABOVE 1000 J/KG AND LAPSE RATES ARE STEEPENING QUICKLY...PUSHING ABOVE 7 C/KM ALREADY. DESPITE WEAKER SHEAR VALUES LESS THAN 30 KTS...CONDITIONS ARE IN PLACE FOR STRONG TO SVR STORM DEVELOPMENT...WITH THE RIGHT TRIGGER. ONE MORE THING TO NOTE IS THE DEVELOPING SEA BREEZE ALONG SOUTHERN LI AND CT PUSHING INLAND. BEHIND THE SEA BREEZE...A MORE STABLE AND COOLER ENVIRONMENT IS EXPECTED...WHICH WILL HELP IN DIMINISHING THE CHANCES FOR TSTORM DEVELOPMENT RIGHT ALONG THE COASTS. MESOSCALE MODELS ARE STILL HAVING A HARD TIME GETTING A READ FOR THE CONVECTION THIS AFTN...HAVING NOT CAPTURED THE CURRENT ACTIVITY. WILL REMAIN WITH THE IDEA THE BEST THREAT IS INLAND NY AND CT FOR DAMAGING WINDS...AND HAIL. EHI VALUES NEAR 3 M2/S2 HINT AT SOME POSSIBLE ROTATION WHICH MAY LEAD TO TOR FORMATION. BUT THIS THREAT LOOKS TO REMAIN NORTH OF OUR CWA. THERE IS A MODERATE RISK OF RIP CURRENTS AT THE OCEAN BEACHES TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... PREVAILING NW STORM FLOW TAKES ANY TSTMS THRU THE CWA TNGT. THE ATMOSPHERE THEN RECHARGES FOR TUE AS A COLD FRONT APPROACHES. FALLING HEIGHTS WILL PROVIDE SYNOPTIC SUPPORT...SO POPS RAMP UP TO LIKELY BY LATE AFTN. THERE WILL REMAIN A SVR THREAT...BUT LLVL HELICITY WILL BE MUCH LWR WITH THE WARM FRONT OUT OF THE PICTURE. TEMPS THRU THE FCST ARE BLEND OF THE MAV/MET...WHICH ARE SUPPORTED BY THE NAM 2M DATA. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... MODEL AGREEMENT AND CONSISTENCY REMAINS WITH THE GFS AND ECMWF FOR TUESDAY NIGHT AND WEDNESDAY WITH THE PASSAGE OF THE COLD FRONT WEDNESDAY. TIMING DIFFERENCES EMERGE FRIDAY INTO THE WEEKEND WITH THE TIMING OF THE FRONTAL SYSTEM IMPACTING THE REGION. THE GFS IS SLOWER THAN THE ECMWF.PREFER A LITTLE SLOWER MOVEMENT WITH THE GFS AS LOW IS ALMOST CUT OFF...THEN GETS PICKED UP WITH THE NORTHERN STREAM SATURDAY NIGHT INTO SUNDAY. WITH THE SLOWER MOVEMENT WILL HAVE WET WEATHER INTO SUNDAY. && .AVIATION /17Z MONDAY THROUGH FRIDAY/... WARM FRONT WILL REMAIN NEARLY STATIONARY OVER CENTRAL AND SOUTHERN NEW ENGLAND TODAY. AT THE SAME TIME...A TROUGH OF LOW PRESSURE REMAINS JUST EAST OF THE CITY TERMINALS. SEA BREEZE AT THE CITY TERMINALS BECOMING MORE UNCERTAIN AS TROUGH OF LOW PRESSURE HAS SET UP TO THE EAST...POTENTIALLY PRECLUDING SEA BREEZE DEVELOPMENT. MAY NEED TO TREND FORECAST TOWARDS SW FOR KLGA AND KJFK THIS AFTERNOON. SCATTERED THUNDERSTORMS POSSIBLE AS EARLY AS 19-20Z NEAR KSWF...AND AS EARLY AS 20-21Z AT THE CITY TERMINALS. WILL PROBABLY NEED TO INCLUDE IN TAFS WITH NEXT UPDATE. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: SEA BREEZE TIMING COULD BE OFF BY AROUND 2 HOURS...AND POSSIBLY MIGHT NOT OCCUR AT ALL THIS AFTERNOON. THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 21Z. KLGA FCSTER COMMENTS: SEA BREEZE TIMING COULD BE OFF BY AROUND 2 HOURS...AND POSSIBLY MIGHT NOT OCCUR AT ALL THIS AFTERNOON. THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 21Z. KEWR FCSTER COMMENTS: THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 20-21Z. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 20-21Z. KHPN FCSTER COMMENTS: SEA BREEZE MIGHT NOT OCCUR AT ALL. THUNDERSTORMS POSSIBLE IN THE VICINITY AS EARLY AS AROUND 20Z. KISP FCSTER COMMENTS: SEA BREEZE TIMING BETWEEN 18Z AND 20Z. .OUTLOOK FOR 12Z TUE THROUGH FRI... .TUE-TUE NIGHT...MORNING IFR POSSIBLE...MAINLY EASTERN TERMINALS. TSTMS LIKELY AFTERNOON INTO THE OVERNIGHT WITH A COLD FRONT. .WED...IMPROVEMENT TO VFR. .WED NIGHT-FRI MORNING...VFR. .FRI AFTERNOON...MVFR OR LOWER POSSIBLE IN SHOWERS/TSTMS. && .MARINE... FORECAST ON TRACK. WITH THE WARM FRONT N OF THE WATERS...PERSISTENT S/SW FLOW WILL BUILD SEAS ON THE OCEAN THRU TUE. WAVEWATCH RUNNING SLIGHTLY HIGH...SO THE DATA HAS BEEN ADJUSTED DOWNWARD BY AROUND A FT THRU THE PERIOD. BEST CHANCE FOR THE 5 FT SEAS WILL BE DURING THE DAY TUE. THERE IS A LOW PROBABILITY THAT SEAS COULD BUILD TO 5 FT LATE TNGT. A CONTINUING SOUTH TO SOUTHWEST FLOW TUESDAY NIGHT INTO WEDNESDAY...AHEAD OF A COLD FRONT...WILL LIKELY KEEP SEAS ON THE OCEAN WATERS AT OR ABOVE 5 FT. HOWEVER...WINDS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT LEVELS. WINDS SHIFT TO THE WEST TO NORTHWEST LATE WEDNESDAY INTO THURSDAY...BEHIND THE COLD FRONT...WITH SUBSIDING SEAS BELOW 5 FT. HIGH PRESSURE BUILDS EAST OF THE WATERS FRIDAY AS A FRONTAL SYSTEM APPROACHES FROM THE SOUTHWEST. WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT LEVELS FRIDAY. && .HYDROLOGY... ANY TSTMS THAT DEVELOP THRU TUE WILL BE CAPABLE OF PRODUCING HEAVY RAIN. RAINFALL RATES MAY EXCEED 1 INCH/HR AT TIMES IN THE STRONGEST ACTIVITY. SOME MINOR URBAN AND POOR DRAINAGE FLOODING CAN BE EXPECTED THRU THE PERIOD. IN ADDITION...THERE IS THE THREAT FOR ISOLD FLASH FLOODING. AROUND A HALF INCH OF RAINFALL IS LIKELY TUESDAY NIGHT INTO WEDNESDAY WITH LOCAL 1 TO 2 INCH AMOUNTS IN HEAVIER SHOWERS AND THUNDERSTORMS. DRY WEATHER RETURNS LATE WEDNESDAY THROUGH THURSDAY. NUISANCE FLOODING IS POSSIBLE TUESDAY NIGHT AND WEDNESDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...MET/12 NEAR TERM...SEARS SHORT TERM...12 LONG TERM...MET AVIATION...JC MARINE...MET/12 HYDROLOGY...MET/12
AREA FORECAST DISCUSSION
NWS ALBANY NY
1243 PM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .NEAR TERM /THROUGH TONIGHT/... LOOKING AT 18Z SPECIAL BALLOON SOUNDING. A WARM FRONT MEANDERS FROM THE GREAT LAKES EASTWARD ACROSS THE SOUTHERN PORTION OF OUR FORECAST AREA AND SOUTHERN NEW ENGLAND. REMNANT OF MCS RIDING ALONG FRONTAL BOUNDARY. ACTIVITY HAS BEEN WEAKENING TO THE NORTH OF THE BOUNDARY IN THE ELEVATED INSTABILITY. HOWEVER TO THE THE SOUTH OF THE BOUNDARY IN THE SURFACE BASED INSTABILITY CONVECTION HAS FIRED. HOWEVER THIS ACTIVITY HAS ALSO WEAKENED. BASED ON SPC MESOSCALE ANALYSIS SBCAPE HAS INCREASED TO 1500 TO 2000 J/KG ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA. DEW POINTS AT KPOU 70 DEGREES AND AT KALB 57 DEGREES. THE POSITION OF THE WARM FRONT HAS BEEN DIFFICULT TO FORECAST HOWEVER IT SHOULD FINALLY LIFT TO OUR NORTH AND EAST THIS EVENING AS ITS ASSOCIATED COLD FRONT APPROACHES. ALOFT THE UPPER RIDGE IS MODELED TO BUILD SLIGHTLY AND CREST OVER REGION THIS AFTERNOON. HEIGHTS WILL BEGIN TO FALL THIS EVENING AS THE RIDGE SHIFTS EASTWARD AND THE UPPER TROUGH APPROACHES. GUIDANCE INDICATES WEAK SHORT WAVES WILL RIDE OVER TOP THE RIDGE. WILL CONTINUE TO KEEP A CLOSE ON THE EYE RADAR AND TRENDS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE TH POTENTIAL TO BECOME SEVERE AS INSTABILITY ACROSS THE REGION INCREASES THROUGH THE DAY. AS OF 1000 AM EDT...CONTINUE TO FOLLOW AN MCS WORKING TOWARD OUR ADIRONDACKS...BUT WEAKENING. SPC GUIDANCE INDICATED ANY REAL SURFACE INSTABILITY WAS WELL SOUTH AND WEST OF THE CAPITAL REGION. HOWEVER...MID LEVEL LAPSE RATES WERE STEEP...UP TO 7C/KM...AS A EML MOVES OVER THE REGION LATER ON. DEWPOINTS WERE ONLY IN THE 50S FROM ALBANY NORTHWARD...BUT JUMP TO THE 60S FURTHER SOUTH AND EVEN EAST OF THE CAPITAL REGION (BERKSHIRES INCLUDED). UNFORTUNATELY MUCH OF THE MESO SCALE MODELS WERE NOT OF MUCH ASSISTANCE...FAILING TO INITIALIZE THE MCS. THE LATEST HRRR FINALLY HAS LOCKED ONTO IT. THE 12Z NAM HOWEVER...STILL DID NOT DEPICT THE FEATURE! SPC WRF DID APPEAR TO CAPTURE THE MCS BUT LOOKED A LITTLE SLOW AND NORTH WITH ITS PROGRESS. A WARM FRONT WAS PERCHED TO THE SOUTH OF THE CAPITAL REGION AND APPEARS TO BE IN NO HURRY TO LIFT NORTHWARD. IT LOOKS AS IF THE MOST ENERGETIC PORTION OF THE MCS WAS IN THE PROCESS OF LIFTING SOUTHWARD...WITH THE WEAKENING PORTION HEADING INTO OUR AREA WELL NORTH OF THE WARM FRONT. HAVE UPDATED GRIDS TO REFLECT THIS TREND AND WE BELIEVE THIS TREND WILL CONTINUE. HOWEVER...THE COLD POOL ASSOCIATED WITH THIS MCS AS WELL AS OUTFLOW BOUNDARY COULD BECOME FOCUS FOR CONVECTION LATER ON. THE WARM FRONT WILL BE THE SYNOPTIC FOCUS FOR ANY STORMS. SINCE IT LOOKS TO BE A LITTLE SLOWER THAN EARLIER THOUGHT...WE NOW BELIEVE THE GREATEST POTENTIAL FOR CONVECTIVE INITIATION MIGHT ACTUALLY BE THE CATSKILLS...MID HUDSON VALLEY..LITCHFIELD COUNTY INTO THE BERKSHIRES...BUT REALLY ANY AREA IS STILL FAIR GAME FOR DEVELOPMENT BY THIS AFTERNOON AS MIXED LAYER CAPES WILL LIKELY INCREASE TO OVER 1000 J/KG NORTH...AND 2000 J/KG SOUTH LATER THIS AFTERNOON. THE QUESTION WILL BE WHERE EXACTLY CONVECTION WILL DEVELOP. STAY TUNED. DID NOT TINKER WITH THE GRIDS FROM 18Z ON. AFTERNOON HIGHS LOOKED REASONABLE BASED ON WHAT WE HAVE SEEN (UNFORTUNATELY WITHOUT THE ASSISTANCE OF OUR RAOB WHICH IS STILL OTS). LOOKS FOR HIGH TEMPERATURES 85-90 VALLEY LOCATIONS FROM ALBANY SOUTHWARD...80-85 HIGHER TERRAIN. TO THE NORTH ALBANY...HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S VALLEY LOCATIONS...70S HIGHER TERRAIN. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... MORE WIDESPREAD AND ORGANIZED STORMS ARE EXPECTED TUESDAY INTO TUESDAY EVENING WITH THE THREAT FOR MORE SEVERE THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MORE WIDESPREAD AND ORGANIZED CONVECTION IS EXPECTED TUESDAY AND TUESDAY NIGHT AHEAD OF THE COLD FRONT WHICH IS EXPECTED TO CROSS THE FA LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AND THE UPPER TROUGH. FOR MUCH OF THE PERIOD FROM TUESDAY THROUGH TUESDAY NIGHT THE FA WILL BE IN THE WARM SECTOR WITH A VERY HUMID AIRMASS REMAINING IN PLACE AS DEWPOINTS REMAIN IN THE 60S TO NEAR 70 THROUGH TUESDAY EVENING. WHILE MID LEVEL LAPSES RATES LESSEN TO 6 TO 6.5 C/KM...MLCAPES REMAIN VERY HIGHS WITH UP TO 4000 J/KG POSSIBLE EARLY TUESDAY AFTERNOON AND INCREASING UPPER JET DYNAMICS AS UPPER JET ENDS UP PUTTING FA IN EQUATORWARD ENTRANCE REGION OF A CYCLONICALLY CURVED 100+ KT JET MAX OVER SRN ONTARIO. BOTH DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO BE POSSIBLE ESPECIALLY DURING THE AFTERNOON INTO THE EVENING HOURS ON TUESDAY. EXPECT HIGHS ON TUESDAY IN THE 80S WITH LOWS TUESDAY NIGHT IN THE MID 50S TO MID 60S. HAVE ADDED ENHANCED WORDING FOR THIS ENTIRE PERIOD TO THE ZONE FORECASTS AND GRIDS. THERE WILL STILL BE A CHANCE OF SHOWERS WEDNESDAY MORNING AFTER WHICH DRY WEATHER IS EXPECTED LATE WEDNESDAY INTO WEDNESDAY NIGHT WITH HIGH PRESSURE GRADUALLY BUILDING FROM THE GREAT LAKES INTO THE NORTHEAST. EXPECT HIGHS ON WEDNESDAY IN THE MID 70S TO LOWER 80S WITH LOWS WEDNESDAY NIGHT IN THE MID 40S TO MID 50S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... USED HPC GUIDANCE STRICTLY (WITH SOME MINOR MODIFICATIONS). HIGH PRESSURE WILL START OUT THE PERIOD BRINGING TEMPERATURES SLIGHTLY COOLER THAN NORMALS FOR LATE MAY/EARLY JUNE. DAYTIME HIGHS WILL BE IN THE 70S...EXCEPT 60S NORTH. NIGHTTIME LOWS WILL BE IN THE 50S SOUTH...40S NORTH THURSDAY AND FRIDAY. THEN...THE IT LOOKS AS IF AN IMPRESSIVE MID LATITUDE LOW PRESSURE AREA WILL APPROACH THE REGION FROM THE SOUTHWEST LATE FRIDAY INTO FRIDAY NIGHT. THIS STORM MIGHT HAVE SOME TROPICAL MOISTURE ASSOCIATED WITH BERYL. EVEN IF IT DOESN/T...LOOKS LIKE A GOOD CHANCE IT WILL BRING A PRETTY GOOD SOAKING RAIN TO THE REGION FRIDAY INTO EARLY SATURDAY. AS LONG AS IT KEEPS MOVING...SOME MID LEVEL DRYING COULD TAKE PLACE LATE SATURDAY...HOWEVER LOW LEVEL MOISTURE WILL LIKELY REMAIN IN PLACE...SO RAIN TAPERS TO SCATTERED SHOWERS...BUT MIGHT NOT COMPLETELY END. CLOUDS LOOK TO HOLD IN PLACE...AND AS A RESULT HIGHS WILL BE MAINLY CONFINED TO THE 60S ON SATURDAY. A BREEZY SOMEWHAT COOL DAY FOR SUNDAY IN THE WAKE OF THE STORM...STILL WITH SOME RESIDUAL CLOUDS...MAINLY NORTH...AND PERHAPS SOME LIGHT RESIDUAL INSTABILITY INDUCED SHOWERS. FOR NOW...JUST CALL IT SLIGHT POPS. HIGH TEMPERATURES WILL BE IN THE 60S HIGHER TERRAIN...LOWER 70S MOST VALLEY AREAS. DRY WEATHER LOOKS TO RETURN MONDAY WITH ANOTHER CANADIAN HIGH PRESSURE BUILDING IN. HIGHS MAINLY IN THE 70S. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... A WARM FRONT WILL SLOWLY LIFT NORTHWARD TODAY AND TONIGHT PROVIDING THE FOCUS FOR SHOWERS AND THUNDERSTORMS...MAINLY THIS AFTERNOON INTO TONIGHT. STRATUS FINALLY BURNED OFF AT KPOU. LOOKING AT PRIMARILY VFR CONDITIONS...EXCEPT MVFR IN ANY THUNDERSTORMS. LIGHT/VARIABLE WINDS WILL BECOME SW TO S BY LATE MORNING...AND INCREASE TO 5-10 KT. WINDS WILL BECOME MAINLY S AT LESS THAN 8 KT MONDAY NIGHT. WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND NEAR ANY TSTMS. TUE...VFR/MVFR. SHRA/TSRA LIKELY. IFR POSSIBLE. WED...MVFR/IFR IMPROVING TO VFR. CHC SHRA/TSRA IN THE AM. THU...VFR...NO SIG WX. FRI...VFR/MVFR. CHC SHOWERS ESP IN AFTERNOON. && .FIRE WEATHER... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .HYDROLOGY... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. INCREASING LEVELS OF HUMIDITY ARE EXPECTED UNTIL THE PASSAGE OF THE COLD FRONT LATE TUESDAY NIGHT OR WEDNESDAY MORNING. IN ADDITION PWATS RISE TO BETWEEN 1.50 AND 1.75 INCHES WITH THE POTENTIAL FOR SOME TRAINING CELLS AND SOME BACKBUILDING CELLS. WHILE THE THREAT OF FLOODING IS NOT EXPECTED TO BE WIDESPREAD...ISOLATED TO SCATTERED AREAS MAY HAVE CONDITIONS SIMILAR TO THOSE WHICH OCCURRED SUNDAY EVENING ACROSS SOUTHEAST PORTIONS OF THE FA WHERE SEVERAL INCHES OF RAIN FELL IN A SHORT PERIOD OF TIME...IN THIS CASE IT WAS IN JUST OVER AND HOUR. THEREFORE FLASH FLOODING WOULD BE THE MAJOR CONCERN...BUT DUE TO THE EXPECTED ISOLATED TO SCATTERED NATURE OF OCCURRENCE DO NOT PLAN ON ISSUING A WATCH AT THIS TIME AND WILL HIGHLIGHT IN THE HWO. && .CLIMATE... NEAR RECORD TO RECORD HIGHS FORECAST FOR TODAY RECORD HIGH TEMPERATURES FOR MAY 28TH... ALBANY NY: 91 DEGREES SET BACK IN 1911 RECORDS DATE BACK TO 1820 GLENS FALLS: 88 DEGREES SET BACK IN 1998 (AND PREVIOUS YEARS) RECORDS DATE BACK TO 1944 POUGHKEEPSIE NY: 90 DEGREES SET BACK IN 1977 RECORDS DATE BACK TO 1949 FOR MORE GO TO OUR CLIMATE PAGE AT: WWW.NWS.NOAA.GOV/CLIMATE/LOCAL_DATA.PHP?WFO=ALY && .EQUIPMENT... NOW LOOKING AT AN 18Z SPECIAL BALLOON. THE ELECTRONICS STAFF HAS INSTALLED THE NEW SIGNAL PROCESSING SYSTEM. WE ARE GOING TO TRY A 17Z SPECIAL BALLOON LAUNCH. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/HWJIV/11 NEAR TERM...IAA/HWJIV/11 SHORT TERM...11 LONG TERM...HWJIV AVIATION...IAA/KL FIRE WEATHER...11 HYDROLOGY...11 CLIMATE...IAA EQUIPMENT...ALY STAFF
AREA FORECAST DISCUSSION
NWS ALBANY NY
1212 PM EDT MON MAY 28 2012 .SYNOPSIS... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .NEAR TERM /THROUGH TONIGHT/... THE ELECTRONICS STAFF HAS INSTALLED THE NEW SIGNAL PROCESSING SYSTEM. WE ARE GOING TO TRY A 17Z SPECIAL BALLOON LAUNCH. A WARM FRONT MEANDERS FROM THE GREAT LAKES EASTWARD ACROSS THE SOUTHERN PORTION OF OUR FORECAST AREA AND SOUTHERN NEW ENGLAND. REMNANT OF MCS RIDING ALONG FRONTAL BOUNDARY. ACTIVITY HAS BEEN WEAKENING TO THE NORTH OF THE BOUNDARY IN THE ELEVATED INSTABILITY. HOWEVER TO THE THE SOUTH OF THE BOUNDARY IN THE SURFACE BASED INSTABILITY CONVECTION HAS FIRED. HOWEVER THIS ACTIVITY HAS ALSO WEAKENED. BASED ON SPC MESOSCALE ANALYSIS SBCAPE HAS INCREASED TO 1500 TO 2000 J/KG ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA. DEW POINTS AT KPOU 70 DEGREES AND AT KALB 57 DEGREES. THE POSITION OF THE WARM FRONT HAS BEEN DIFFICULT TO FORECAST HOWEVER IT SHOULD FINALLY LIFT TO OUR NORTH AND EAST THIS EVENING AS ITS ASSOCIATED COLD FRONT APPROACHES. WILL CONTINUE TO KEEP A CLOSE ON THE EYE RADAR AND TRENDS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE TH POTENTIAL TO BECOME SEVERE AS INSTABILITY ACROSS THE REGION INCREASES THROUGH THE DAY. ALOFT THE UPPER RIDGE IS MODELED TO BUILD SLIGHTLY AND CREST OVER REGION THIS AFTERNOON. HEIGHTS WILL BEGIN TO FALL THIS EVENING AS THE RIDGE SHIFTS EASTWARD AND THE UPPER TROUGH APPROACHES. GUIDANCE INDICATES WEAK SHORT WAVES WILL RIDE OVER TOP THE RIDGE. AS OF 1000 AM EDT...CONTINUE TO FOLLOW AN MCS WORKING TOWARD OUR ADIRONDACKS...BUT WEAKENING. SPC GUIDANCE INDICATED ANY REAL SURFACE INSTABILITY WAS WELL SOUTH AND WEST OF THE CAPITAL REGION. HOWEVER...MID LEVEL LAPSE RATES WERE STEEP...UP TO 7C/KM...AS A EML MOVES OVER THE REGION LATER ON. DEWPOINTS WERE ONLY IN THE 50S FROM ALBANY NORTHWARD...BUT JUMP TO THE 60S FURTHER SOUTH AND EVEN EAST OF THE CAPITAL REGION (BERKSHIRES INCLUDED). UNFORTUNATELY MUCH OF THE MESO SCALE MODELS WERE NOT OF MUCH ASSISTANCE...FAILING TO INITIALIZE THE MCS. THE LATEST HRRR FINALLY HAS LOCKED ONTO IT. THE 12Z NAM HOWEVER...STILL DID NOT DEPICT THE FEATURE! SPC WRF DID APPEAR TO CAPTURE THE MCS BUT LOOKED A LITTLE SLOW AND NORTH WITH ITS PROGRESS. A WARM FRONT WAS PERCHED TO THE SOUTH OF THE CAPITAL REGION AND APPEARS TO BE IN NO HURRY TO LIFT NORTHWARD. IT LOOKS AS IF THE MOST ENERGETIC PORTION OF THE MCS WAS IN THE PROCESS OF LIFTING SOUTHWARD...WITH THE WEAKENING PORTION HEADING INTO OUR AREA WELL NORTH OF THE WARM FRONT. HAVE UPDATED GRIDS TO REFLECT THIS TREND AND WE BELIEVE THIS TREND WILL CONTINUE. HOWEVER...THE COLD POOL ASSOCIATED WITH THIS MCS AS WELL AS OUTFLOW BOUNDARY COULD BECOME FOCUS FOR CONVECTION LATER ON. THE WARM FRONT WILL BE THE SYNOPTIC FOCUS FOR ANY STORMS. SINCE IT LOOKS TO BE A LITTLE SLOWER THAN EARLIER THOUGHT...WE NOW BELIEVE THE GREATEST POTENTIAL FOR CONVECTIVE INITIATION MIGHT ACTUALLY BE THE CATSKILLS...MID HUDSON VALLEY..LITCHFIELD COUNTY INTO THE BERKSHIRES...BUT REALLY ANY AREA IS STILL FAIR GAME FOR DEVELOPMENT BY THIS AFTERNOON AS MIXED LAYER CAPES WILL LIKELY INCREASE TO OVER 1000 J/KG NORTH...AND 2000 J/KG SOUTH LATER THIS AFTERNOON. THE QUESTION WILL BE WHERE EXACTLY CONVECTION WILL DEVELOP. STAY TUNED. DID NOT TINKER WITH THE GRIDS FROM 18Z ON. AFTERNOON HIGHS LOOKED REASONABLE BASED ON WHAT WE HAVE SEEN (UNFORTUNATELY WITHOUT THE ASSISTANCE OF OUR RAOB WHICH IS STILL OTS). LOOKS FOR HIGH TEMPERATURES 85-90 VALLEY LOCATIONS FROM ALBANY SOUTHWARD...80-85 HIGHER TERRAIN. TO THE NORTH ALBANY...HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S VALLEY LOCATIONS...70S HIGHER TERRAIN. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... MORE WIDESPREAD AND ORGANIZED STORMS ARE EXPECTED TUESDAY INTO TUESDAY EVENING WITH THE THREAT FOR MORE SEVERE THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY ALSO PRODUCE HEAVY RAINFALL. MORE WIDESPREAD AND ORGANIZED CONVECTION IS EXPECTED TUESDAY AND TUESDAY NIGHT AHEAD OF THE COLD FRONT WHICH IS EXPECTED TO CROSS THE FA LATE TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING AND THE UPPER TROUGH. FOR MUCH OF THE PERIOD FROM TUESDAY THROUGH TUESDAY NIGHT THE FA WILL BE IN THE WARM SECTOR WITH A VERY HUMID AIRMASS REMAINING IN PLACE AS DEWPOINTS REMAIN IN THE 60S TO NEAR 70 THROUGH TUESDAY EVENING. WHILE MID LEVEL LAPSES RATES LESSEN TO 6 TO 6.5 C/KM...MLCAPES REMAIN VERY HIGHS WITH UP TO 4000 J/KG POSSIBLE EARLY TUESDAY AFTERNOON AND INCREASING UPPER JET DYNAMICS AS UPPER JET ENDS UP PUTTING FA IN EQUATORWARD ENTRANCE REGION OF A CYCLONICALLY CURVED 100+ KT JET MAX OVER SRN ONTARIO. BOTH DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO BE POSSIBLE ESPECIALLY DURING THE AFTERNOON INTO THE EVENING HOURS ON TUESDAY. EXPECT HIGHS ON TUESDAY IN THE 80S WITH LOWS TUESDAY NIGHT IN THE MID 50S TO MID 60S. HAVE ADDED ENHANCED WORDING FOR THIS ENTIRE PERIOD TO THE ZONE FORECASTS AND GRIDS. THERE WILL STILL BE A CHANCE OF SHOWERS WEDNESDAY MORNING AFTER WHICH DRY WEATHER IS EXPECTED LATE WEDNESDAY INTO WEDNESDAY NIGHT WITH HIGH PRESSURE GRADUALLY BUILDING FROM THE GREAT LAKES INTO THE NORTHEAST. EXPECT HIGHS ON WEDNESDAY IN THE MID 70S TO LOWER 80S WITH LOWS WEDNESDAY NIGHT IN THE MID 40S TO MID 50S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... USED HPC GUIDANCE STRICTLY (WITH SOME MINOR MODIFICATIONS). HIGH PRESSURE WILL START OUT THE PERIOD BRINGING TEMPERATURES SLIGHTLY COOLER THAN NORMALS FOR LATE MAY/EARLY JUNE. DAYTIME HIGHS WILL BE IN THE 70S...EXCEPT 60S NORTH. NIGHTTIME LOWS WILL BE IN THE 50S SOUTH...40S NORTH THURSDAY AND FRIDAY. THEN...THE IT LOOKS AS IF AN IMPRESSIVE MID LATITUDE LOW PRESSURE AREA WILL APPROACH THE REGION FROM THE SOUTHWEST LATE FRIDAY INTO FRIDAY NIGHT. THIS STORM MIGHT HAVE SOME TROPICAL MOISTURE ASSOCIATED WITH BERYL. EVEN IF IT DOESN/T...LOOKS LIKE A GOOD CHANCE IT WILL BRING A PRETTY GOOD SOAKING RAIN TO THE REGION FRIDAY INTO EARLY SATURDAY. AS LONG AS IT KEEPS MOVING...SOME MID LEVEL DRYING COULD TAKE PLACE LATE SATURDAY...HOWEVER LOW LEVEL MOISTURE WILL LIKELY REMAIN IN PLACE...SO RAIN TAPERS TO SCATTERED SHOWERS...BUT MIGHT NOT COMPLETELY END. CLOUDS LOOK TO HOLD IN PLACE...AND AS A RESULT HIGHS WILL BE MAINLY CONFINED TO THE 60S ON SATURDAY. A BREEZY SOMEWHAT COOL DAY FOR SUNDAY IN THE WAKE OF THE STORM...STILL WITH SOME RESIDUAL CLOUDS...MAINLY NORTH...AND PERHAPS SOME LIGHT RESIDUAL INSTABILITY INDUCED SHOWERS. FOR NOW...JUST CALL IT SLIGHT POPS. HIGH TEMPERATURES WILL BE IN THE 60S HIGHER TERRAIN...LOWER 70S MOST VALLEY AREAS. DRY WEATHER LOOKS TO RETURN MONDAY WITH ANOTHER CANADIAN HIGH PRESSURE BUILDING IN. HIGHS MAINLY IN THE 70S. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... A WARM FRONT WILL SLOWLY LIFT NORTHWARD TODAY AND TONIGHT PROVIDING THE FOCUS FOR SHOWERS AND THUNDERSTORMS...MAINLY THIS AFTERNOON INTO TONIGHT. STRATUS FINALLY BURNED OFF AT KPOU. LOOKING AT PRIMARILY VFR CONDITIONS...EXCEPT MVFR IN ANY THUNDERSTORMS. LIGHT/VARIABLE WINDS WILL BECOME SW TO S BY LATE MORNING...AND INCREASE TO 5-10 KT. WINDS WILL BECOME MAINLY S AT LESS THAN 8 KT MONDAY NIGHT. WINDS WILL BE MUCH STRONGER...AND VARIABLE IN DIRECTION IN AND NEAR ANY TSTMS. TUE...VFR/MVFR. SHRA/TSRA LIKELY. IFR POSSIBLE. WED...MVFR/IFR IMPROVING TO VFR. CHC SHRA/TSRA IN THE AM. THU...VFR...NO SIG WX. FRI...VFR/MVFR. CHC SHOWERS ESP IN AFTERNOON. && .FIRE WEATHER... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. && .HYDROLOGY... A WARM FRONT WILL LIFT NORTHWARD TODAY PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. ANY THUNDERSTORMS THAT DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE AND PRODUCE HEAVY RAINFALL. WITH THE PASSAGE OF THE BOUNDARY...A WARMER AND MORE HUMID AIRMASS WILL BE USHERED IN. MORE WIDESPREAD SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY AND TUESDAY NIGHT AS A COLD FRONT APPROACHES FROM THE WEST AND MOVES ACROSS THE REGION. THESE THUNDERSTORMS MAY ALSO BE SEVERE AND PRODUCE HEAVY RAINFALL. INCREASING LEVELS OF HUMIDITY ARE EXPECTED UNTIL THE PASSAGE OF THE COLD FRONT LATE TUESDAY NIGHT OR WEDNESDAY MORNING. IN ADDITION PWATS RISE TO BETWEEN 1.50 AND 1.75 INCHES WITH THE POTENTIAL FOR SOME TRAINING CELLS AND SOME BACKBUILDING CELLS. WHILE THE THREAT OF FLOODING IS NOT EXPECTED TO BE WIDESPREAD...ISOLATED TO SCATTERED AREAS MAY HAVE CONDITIONS SIMILAR TO THOSE WHICH OCCURRED SUNDAY EVENING ACROSS SOUTHEAST PORTIONS OF THE FA WHERE SEVERAL INCHES OF RAIN FELL IN A SHORT PERIOD OF TIME...IN THIS CASE IT WAS IN JUST OVER AND HOUR. THEREFORE FLASH FLOODING WOULD BE THE MAJOR CONCERN...BUT DUE TO THE EXPECTED ISOLATED TO SCATTERED NATURE OF OCCURRENCE DO NOT PLAN ON ISSUING A WATCH AT THIS TIME AND WILL HIGHLIGHT IN THE HWO. && .CLIMATE... NEAR RECORD TO RECORD HIGHS FORECAST FOR TODAY RECORD HIGH TEMPERATURES FOR MAY 28TH... ALBANY NY: 91 DEGREES SET BACK IN 1911 RECORDS DATE BACK TO 1820 GLENS FALLS: 88 DEGREES SET BACK IN 1998 (AND PREVIOUS YEARS) RECORDS DATE BACK TO 1944 POUGHKEEPSIE NY: 90 DEGREES SET BACK IN 1977 RECORDS DATE BACK TO 1949 FOR MORE GO TO OUR CLIMATE PAGE AT: WWW.NWS.NOAA.GOV/CLIMATE/LOCAL_DATA.PHP?WFO=ALY && .EQUIPMENT... THE ELECTRONICS STAFF HAS INSTALLED THE NEW SIGNAL PROCESSING SYSTEM. WE ARE GOING TO TRY A 17Z SPECIAL BALLOON LAUNCH. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...IAA/HWJIV/11 NEAR TERM...IAA/HWJIV/11 SHORT TERM...11 LONG TERM...HWJIV AVIATION...IAA/KL FIRE WEATHER...11 HYDROLOGY...11 CLIMATE...IAA EQUIPMENT...ALY STAFF
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
134 PM EDT MON MAY 28 2012 .AVIATION... THE WEST COAST SEA BREEZE IS PUSHING ACROSS THE AREA...AS THE EAST COAST SEA BREEZE HAS DEVELOPED AND PUSH JUST WEST OF THE EAST COAST TAF SITES. THE WEST COAST SEA BREEZE WILL CONTINUE TO MOVE EAST ACROSS SOUTH FLORIDA THIS AFTERNOON INTO THIS EVENING...AS THE EAST COAST SEA BREEZE REMAINS NEARLY STATIONARY JUST EAST OF THE EAST COAST TAF SITES. SO WILL CONTINUE THE SOUTHEAST WIND FLOW AROUND 15 KTS WITH GUSTS UP TO 20 TO 21Z FOR THIS AFTERNOON BEFORE DECREASING TO LIGHT AND VARIABLE AFTER 03Z TONIGHT FOR THE EAST COAST TAF SITES. FOR KAPF TAF SITE...THE WINDS WILL REMAIN SOUTHWEST AT 10 TO 15 KNOTS WITH GUSTS UP TO 18Z BEFORE DECREASING TO LIGHT AND VARIABLE AFTER 02Z. SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE TO DEVELOP ALONG THE WEST COAST SEA BREEZE AND MOVE NORTHEAST TOWARDS KPBI...KFLL...AND KFXE TAF SITES THIS AFTERNOON. SO WILL CONTINUE THE VCTS FOR THESE TAF SITES THROUGH 01Z ALONG WITH A TEMPO GROUP BETWEEN 19Z AND 23Z FOR REDUCTIONS OF VIS AND CEILING DOWN TO MVFR CONDITIONS WITH THE SHOWERS AND THUNDERSTORMS. FOR KMIA...KOPF...AND KTMB THERE SHOULD ONLY BE SHOWERS THIS AFTERNOON INTO THIS EVENING. SO WILL CONTINUE THE VCSH FOR THESE TAF SITES THROUGH 03Z. AFTER 03Z...THE WEATHER SHOULD GO DRY SO WILL CONTINUE THE DRY WEATHER AT ALL OF THE EAST COAST TAF SITES AFTER 3Z TONIGHT. KAPF TAF SITE SHOULD ALSO REMAIN DRY THIS AFTERNOON INTO TONIGHT ALONG WITH VFR CONDITIONS. && .AVIATION...54/BNB .PREV DISCUSSION... /ISSUED 913 AM EDT MON MAY 28 2012/ UPDATE... ONLY SLIGHT MODIFICATIONS WERE MADE THIS MORNING BASED ON THE MORNING ANALYSIS AND THE LATEST MODEL GUIDANCE. THE MORNING VAPOR LOOP SHOWED A DRY SLOT ACROSS SOUTH FLORIDA WITH MOST OF THE DEEP LAYER MOISTURE REMAINING OVER N/CENTRAL FL ASSOCIATED WITH BERYL. THIS LINES UP WELL WITH THE MORNING UPPER AIR SOUNDING AT MFL...WHICH INDICATED PWAT VALUES DOWN FROM 1.68 LAST NIGHT TO 1.27 INCHES THIS MORNING. PRIMARY FLOW THROUGH THE COLUMN WILL REMAIN OUT OF THE SSW TODAY...WHICH FAVORS AFTERNOON CONVECTION SETTING UP OVER THE NORTH AND EASTERN HALF OF THE PENINSULA...OR ANYWHERE FROM INLAND MIAMI-DADE TO PALM BEACH COUNTIES. THE LATEST WRF AND HRRR MODEL REFLECTIVITY OUTPUT LINES UP WELL THIS GENERAL PATTERN AND INDICATES MOST OF THE AFTERNOON CONVECTION INITIATING AROUND AND AFTER 18Z AND CONTINUING THROUGH THE EARLY EVENING PERIOD BEFORE TRENDING DOWN THROUGH THE MID/LATE EVENING HOURS AS TYPICALLY OBSERVED. THE PRIMARY THREATS WITH THIS ACTIVITY TODAY WILL BE FREQUENT LIGHTNING...GUSTY WINDS (WINDEX IN THE 40 TO 60 MPH RANGE)...SMALL HAIL AND PERIODS WITH HEAVY RAINFALL. AS A RESULT...WE HAVE SLIGHTLY TWEAKED THE RAINFALL PROBABILITIES ACROSS THE AREA THROUGH THIS TIME TODAY. OTHERWISE...THE PREVIOUS FORECAST PACKAGE REMAINS ON TRACK WITH NO OTHER CHANGES NECESSARY. 85/AG && PREV DISCUSSION... /ISSUED 701 AM EDT MON MAY 28 2012/ AVIATION... VFR CONDITIONS WITH LIGHT WINDS AT 5 KNOTS OR LESS SHOULD PREVAIL THROUGH THE MID MORNING HOURS TODAY. MEAN WEST-SOUTHWEST WIND FLOW SHOULD INTERACT WITH DEVELOPING SEA BREEZES ALONG THE EAST COAST TO INDUCE THE DEVELOPMENT OF TSTMS BY EARLY AFTERNOON. ONCE AGAIN, A SOUTHWESTERLY FLOW ALOFT SHOULD STEER ANY STORM TOWARD THE EAST COAST CLOSE TO THE ERN TERMINALS. WL EXPECT THE SOUTHWEST FLOW TO KEEP KAPF FREE OF ANY STORM BY PUSHING ANY DEVELOPMENT FURTHER INLAND. && AVIATION...BNB/RGH PREV DISCUSSION... /ISSUED 358 AM EDT MON MAY 28 2012/ DISCUSSION... AS TROPICAL STORM BERYL CONTINUES ON ITS WESTWARD TRACK TODAY AND THEN FORECAST TO MOVE NORTHEAST EARLY TUESDAY...WINDS ACROSS THE REGION WILL BE SOUTHWESTERLY TO SOUTHERLY THROUGH AT MID-WEEK. UNDER THIS REGIME...THE FORECAST FOR THE WORK WEEK IS FOR SHOWERS AND THUNDERSTORMS EXPECTED ACROSS THE SOUTH FLORIDA PENINSULA MAINLY DURING THE LATER PART OF THE AFTERNOON AND INTO THE EVENING HOURS. THE SUITE OF MODEL GUIDANCE CONSISTENTLY INDICATED LOW LEVEL SOUTHWESTERLY FLOW THROUGH AT LEAST MID WEEK WHICH WILL FAVOR AFTERNOON CONVECTION ACROSS THE EASTERN HALF OF THE PENINSULA. THE LATEST GUIDANCE ALSO INDICATED AN UPPER LEVEL TROUGH PERSISTING ACROSS THE EASTERN GULF THROUGH AT LEAST MID WEEK WHICH WILL HELP TO ENHANCE AFTERNOON CONVECTION. IN ADDITION THE SOUTHERLY FLOW WILL HELP TO MAINTAIN WARMER TEMPERATURES ACROSS THE REGION WITH THE ATLANTIC COAST METRO AREAS POSSIBLY REACHING THE UPPER 80S EACH DAY BEFORE THE CONVECTION STARTS WITH NEAR 90 TEMPERATURES POSSIBLE IN THE WESTERN METRO AREAS. FOR TODAY NEED TO EMPHASIZE THE CHANCE OF A FEW STRONG THUNDERSTORMS...AGAIN MAINLY EXPECTED ACROSS THE EASTERN HALF OF THE PENINSULA DURING THE LATE AFTERNOON AND EVEN HOURS. ACCORDING TO THE LATEST GUIDANCE THE STRONGER UPPER LEVEL WINDS ARE CURRENTLY ACROSS THE FLORIDA STRAITS AND ARE FORECAST TO LIFT NORTHWARD AS THE DAY PROGRESSES...WITH MAINLY THE SOUTHERN PORTIONS OF THE PENINSULA AFFECTED. BUT THIS WILL HELP TO MAINTAIN UPPER LEVEL SPEED DIVERGENCE AND HELP TO MAINTAIN A FEW STRONG THUNDERSTORMS. IN ADDITION RECENT WATER VAPOR IMAGERY INDICATES MID TO UPPER LEVEL DRIER AIR ACROSS SOUTH FLORIDA WHICH IS ON THE SOUTHERN PERIPHERY OF TROPICAL STORM BERYL. THIS COULD ADD TO THE POTENTIAL FOR HAIL WITH THE STRONGEST THUNDERSTORMS TODAY. MARINE... AS TROPICAL STORM BERYL CONTINUES ON ITS WESTWARD TRACK TODAY AND THEN FORECAST TO MOVE NORTHEAST EARLY TUESDAY...ITS PRESENCE ACROSS THE SOUTHEAST U.S. WILL HELP TO MAINTAIN A WEAKENED PRESSURE GRADIENT ACROSS THE SOUTH FLORIDA GULF AND ATLANTIC WATERS THROUGH AT LEAST MID-WEEK WITH A MORE SOUTHERLY FLOW ACROSS THE REGION. WINDS ACROSS THE LOCAL ATLANTIC WATERS WILL SLOWLY SUBSIDE TODAY INTO TUESDAY WITH GULF STREAM SEAS SLOWLY SUBSIDING. WINDS AND SEAS ARE FORECAST TO REMAIN WELL BELOW ADVISORY LEVELS ACROSS THE REGIONAL WATERS THROUGH AT LEAST THURSDAY. FIRE WEATHER... NO FIRE WEATHER CONCERNS. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 74 88 74 88 / 30 40 30 40 FORT LAUDERDALE 76 89 76 89 / 30 40 30 40 MIAMI 76 89 75 89 / 30 40 30 40 NAPLES 74 88 73 88 / 30 30 30 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ DISCUSSION/MARINE/FIRE...60/BD AVIATION/RADAR...47/RGH
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
153 PM EDT MON MAY 28 2012 .PREV DISCUSSION... /ISSUED 1011 AM EDT MON MAY 28 2012/ UPDATE...NO SIGNIFICANT CHANGES PLANNED FOR THIS UPDATE AS POP GRIDS LOOK IN GOOD SHAPE WITH SHARP GRADIENT GRADUALLY EXPANDING AS RAIN BANDS MOVE FURTHER AWAY FROM CENTER. FIRST SUCH BAND MOVING INTO THE SOUTHEAST GEORGIA COAST AT THIS HOUR AND WITH SOME HEATING...ALTHOUGH LIMITED BY ABUNDANT CLOUD COVER...SHOULD SEE INCREASE IN COVERAGE FOR SOUTHEAST CORNER THROUGH EARLY AFTERNOON. BIGGER QUESTIONS BECOMES HOW FAR NORTH SHOWERS MAKE IT THIS AFTERNOON. RAP FOR THE NEXT 6 HOURS NOT SHOWING MUCH SURFACE BASED CAPE INCREASE AND SHOULD ONLY SEE VALUES APPROACH 1000 J/KG OVER A SMALL SECTION OF CENTRAL GEORGIA. HRRR IS REALLY THE ONLY MODEL BULLISH ABOUT BRING RAINBAND SHOWERS INTO NORTH GEORGIA AND FEEL CURRENTLY ADVERTISED LOW END CHANCE GRIDS HANDLE THIS WELL. WILL UPDATE WIND FIELDS BASED ON NEW GUIDANCE...OTHERWISE WILL HOLD WITH WHAT WE HAVE GRID WISE. PREV DISCUSSION... /ISSUED 754 AM EDT MON MAY 28 2012/ PREV DISCUSSION... /ISSUED 353 AM EDT MON MAY 28 2012/ GUSTY WINDS OVER AREAS SOUTH OF I-85 AND PERIODS OF HEAVY RAIN EXPECTED IN FAR SOUTHERN TIER OF COUNTIES FROM TROPICAL STORM BERYL TODAY... SHORT TERM /TODAY THROUGH TUESDAY/... PRIMARY CONCERN IN THE SHORT TERM PERIOD IS IMPACT OF TS BERYL WHICH MADE LANDFALL NEAR JACKSONVILLE FL AROUND MIDNIGHT. OUTER BAND OF SHOWERS MOVED THROUGH SOME SE COUNTIES WITH SOME GUSTS OF 20 TO 25KTS BUT THIS BAND HAS DISSIPATED WITH GUSTS BACK DOWN TO 20KTS OR LESS. GUSTY WINDS WILL LIKELY BE THE MAIN IMPACT OF BERYL ACROSS AREAS SOUTH OF I-85 WHERE WINDS COULD GUST TO AROUND 25 MPH APPROACHING 35 MPH SOUTH AND EAST OF MACON...JUST BELOW WIND ADVISORY CRITERIA. LATEST HPC QPF CONTINUES DOWNWARD TREND OF AMOUNTS OF SOUTHERN CWA TODAY AND TONIGHT. 00Z ECMWF AND 00Z NAM ALSO KEEP BULK OF PRECIP OVER SOUTHERN COUNTIES TODAY THOUGH 00Z GFS AND 21Z SREF DO INDICATE SOME POTENTIAL FOR SCT SHRA/TSRA THIS AFTERNOON. BY TONIGHT...CONVECTION WILL VERY LIKELY BE CONTAINED NEAR THE CENTER OF THE REMNANTS OF BERYL WHICH WILL BE SOMEWHERE OVER FAR S GA AT THAT TIME. TUESDAY...REMNANTS OF BERYL WILL INTERACT WITH AN APPROACHING FRONT SWEEPING IN WITH THE HELP OF FAIRLY STRONG WESTERLIES OVER THE OH VALLEY AND MIDWEST. HAVE KEPT POPS IN CHC TO LKLY CATEGORY BUT COULD BE A LITTLE MORE WIDESPREAD AS THE FCST PROGRESSES. TWEAKED TEMPS BASED ON RECENT 30 DAY BIASES AND EXPECTATIONS FOR LOWER DIURNAL RANGES DUE TO TS BERYL. MIN TEMPS HAVE BEEN MUCH WARMER THAN GUIDANCE RECENTLY /CURRENT TEMPS STILL IN LOW TO MID 70S...ABOUT 4 TO 8 DEGS HIGHER THAN 12Z MAV/MET GUIDANCE FCST FOR THIS TIME/. THIS TREND SHOULD CONTINUE UNTIL DRIER AIRMASS MOVES THROUGH. SNELSON LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... THE REMNANTS OF TROPICAL STORM BERYL IS FORECAST TO MOVE TO THE NORTHEAST AND EXIT THE STATE ALONG THE SC COAST TUESDAY NIGHT OR EARLY WEDNESDAY MORNING. THE GFS AND ECMWF HAVE A FAIRLY GOOD HANDLE ON THIS MOVEMENT...WITH A DRIER NORTHERLY WIND FLOW IN ITS WAKE ON WEDNESDAY. WILL SHOW A SLIGHT CHANCE OF THUNDER ON WEDNESDAY AS BOTH MODELS SHOW AN ACTIVE WESTERLY FLOW ALOFT AND A WEAK SURFACE TROUGH STILL ACROSS THE STATE. RAIN CHANCES SIGNIFICANTLY INCREASE FOR THURSDAY AND FRIDAY AS GFS AND ECMWF AGREE ON AN UPPER LOW AND ASSOCIATED FRONTAL BOUNDARY KICKING EAST OF THE PLAINS ON THURSDAY AND DRAGGING A COLD FRONT ACROSS THE FORECAST AREA FRIDAY NIGHT. EXPECT THE GREATER THUNDERSTORM THREAT TO BE ON FRIDAY AHEAD OF THE APPROACHING FRONT...WITH 2000-2500 CAPE...40KT LOW LEVEL JET AND MODERATE DIFFLUENT FLOW ALOFT. TOTAL RAINFALL AMOUNTS FOR THURSDAY AND FRIDAY WILL LIKELY BE LESS THAN AN INCH. MODELS SHOW CLEARING CONDITIONS EARLY SATURDAY...WITH DRY HIGH PRESSURE SETTLING IN FOR THE WEEKEND. 39 FIRE WEATHER... WINDS ACROSS AREAS SOUTH OF I-85 WILL APPROACH FIRE DANGER CRITERIA TODAY. AS MENTIONED PREVIOUSLY...OCCASIONAL SHOWERS SHOULD MITIGATE ANY DANGEROUS FIRE WEATHER CONDITIONS. WILL NEED TO MONITOR THIS THROUGH THE DAY IN CASE PRECIP BECOMES MORE CONCENTRATED AROUND TS BERYL LEAVING THINGS HIGH AND DRY IN MIDDLE GA. FUELS CONTINUE TO REMAIN VERY LOW. HYDROLOGY... MAX RAINFALL IN SE PARTS OF CWA NOW FCST TO REMAIN AT OR BELOW 2 INCHES. WITH DRY ANTECEDENT CONDITIONS AND CORRESPONDING HIGH FFG VALUES OF 4 TO 5 INCHES IN 3 HOURS...WILL NOT BE ISSUING ANY TYPE OF FLOOD WATCH. PRECIP WITH OUTER BAND THAT MOVED THROUGH EARLIER THIS MORNING ONLY PRODUCED A TENTH TO A QUARTER INCH SO FAR. && .AVIATION... 18Z UPDATE... AS TROPICAL DEPRESSION BERYL CONTINUES ITS TRACK INLAND...RAINBANDS CONTINUE TO EXPAND AWAY FROM THE CENTER AND INCREASING COVERAGE AIDED BY EARLY AFTERNOON HEATING. EXPECTING SHRA TO AFFECT AHN AND MCN FIRST WITH BRIEF GUSTS POSSIBLE WITH EACH BAND. DRY AIR STILL IN PLACE ALOFT WILL MAKE IT A LATER START FOR THE ATL SITES BUT HAVE INCLUDED A SHORT TERM TEMPO THERE FOR LATER THIS AFTERNOON. AS STORM PIVOTS NE TONIGHT...RAIN AXIS WILL SET UP BETWEEN MCN AND AHN WITH PREDOMINANT SHRA THROUGH MUCH OF TUE. LOW LEVEL MOISTURE WILL CONTINUE TO INCREASE INTO TONIGHT WITH MVFR CONDITIONS LIKELY AND WILL NEED TO MONITOR FOR POSSIBLE IFR CONDITIONS AS WELL TOWARD DAYBREAK TUE FOR ALL SITES. //ATL CONFIDENCE...18Z UPDATE... MEDIUM CONFIDENCE ON SHRA/TSRA TIMING. HIGH CONFIDENCE ON ALL OTHER ELEMENTS. DEESE && .PRELIMINARY POINT TEMPS/POPS... ATHENS 87 69 86 67 / 40 30 60 40 ATLANTA 86 71 85 70 / 30 30 50 20 BLAIRSVILLE 84 66 82 63 / 30 30 60 40 CARTERSVILLE 88 68 88 67 / 20 20 40 20 COLUMBUS 88 71 89 71 / 50 30 40 20 GAINESVILLE 85 69 85 67 / 30 30 60 30 MACON 87 71 86 68 / 50 40 60 30 ROME 90 68 89 67 / 20 20 40 20 PEACHTREE CITY 86 68 85 67 / 40 30 40 20 VIDALIA 84 72 83 70 / 80 70 70 50 && .FFC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...DEESE LONG TERM....01 AVIATION...DEESE
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
404 PM EDT MON MAY 28 2012 .SHORT TERM... /TONIGHT THROUGH TUESDAY NIGHT/ FOCUS ON HEAT INTO THIS EVENING AND CONVECTIVE CHANCES AHEAD OF APPROACHING COLD FRONT. STRONG MIXING OF WARM LL TEMPS HAS ALLOWED FOR HIGHS ACROSS THE AREA TO CLIMB INTO THE 90 TO 95 DEGREE RANGE. MUCH LIKE YESTERDAY...THIS SAME MIXING HAS ALLOWED FOR SLIGHTLY DRIER AIR ALOFT TO BE MIXED DOWN...LOWERING DEWPTS INTO THE MID 50S TO NEAR 60 VS LOWER TO MIDDLE 60S. CONVECTION ASSOCIATED WITH A PRE-FRONTAL TROUGH HAS WEAKENED CONSIDERABLY OVER THE PAST SEVERAL HOURS...PARTIALLY AS A RESULT OF THE DRIER CONDITIONS AND TROUGH MOVING AWAY FROM BEST DYNAMICS. CAN`T RULE OUT A STRAY SHOWER OR STORM ON THIS FEATURE...BUT NOT WORTHY OF ANYTHING OTHER THAN SLGT CHC. HRRR MODEL SHOWS SFC COLD FRONT...LOCATED FROM WISCONSIN TO EASTERN IOWA...MAY BEGIN TO CATCH UP OVER THE NEXT COUPLE OF HOURS AS NEXT JET STREAK APPROACHES. MOISTURE WAS POOLING BEHIND THE TROUGH AND AHEAD OF THE COLD FRONT WITH DEWPTS IN THE 64 TO NEARLY 70 DEGREE RANGE. CONVECTION SHOULD CONTINUE TO SPREAD SW WARD ALONG THE FRONT AND MOVE EAST TOWARDS THE AREA. FAR WESTERN LOCATIONS MAY SEE STORMS MOVE IN BETWEEN 23 AND 1Z AND THEN WORK EAST FROM THERE. WITH LOSS OF PEAK HEATING...SOME QUESTION AS TO COVERAGE AND INTENSITY OF ACTIVITY AS IT MOVES THROUGH THE REGION. WILL MAINTAIN LIKELY POPS TONIGHT BUT ATTEMPT TO ADD MORE DETAIL ON TIMING. SVR CHANCES STILL IN PLACE ALONG THE FRONT THIS EVENING WITH STEEP MID LEVEL LAPSE RATES AND CAPES IN THE 2000-2500 J/KG RANGE. THIS INSTABILITY WILL DECREASE WITH TIME AND BEST JET DYNAMICS TO PASS NW OF THE AREA. IF A WELL ESTABLISHED LINE CAN MATERIALIZE...INCREASED CHANCES FOR DAMAGING WINDS WOULD EXIST WITH AT LEAST UNIDIRECTIONAL WIND FIELD IN PLACE WITH SOME INCREASE IN SHEAR. FRONT WILL BE EXITING THE AREA TUESDAY MORNING. HAVE CONTINUED DOWNWARD TREND ON POPS WITH DRY CONDITIONS NOW STARTING AT 15Z. MAIN PUSH OF COLDER AIR WILL STILL BE BEHIND A BIT BUT ARRIVE BY TUES NGT ALLOWING FOR COOLER AND LESS HUMID CONDITIONS INTO THE LONG TERM. && .LONG TERM... WEDNESDAY THROUGH MONDAY. DISPARAGING DETERMINISTIC MODEL RESPONSES SUGGEST STRONG LEAN ONTO CONSISTENCY IN ORDER WRT LATER PDS. LEAN TOWARD ECMWF WITH AT LEAST SOME RUN TO RUN SEMBLANCE. GEM STILL APPEARS TO DIG NEXT SYSTEM /INTO EPAC ATTM/ TOO FAR SWD GOING INTO DY4 WITH LATEST OP GFS AFFORDING MIDDLE OF ROAD APPROACH TO THE AGAIN MORE FAVORED HIR BELTED ECMWF GIVEN OVERALL LOW AMPLITUDE FLOW PATTERN. SRN/SERN CWA REMAINS KEYED ON ISENT UPGLIDE WITH STRONG OH VLY CYCLOGENESIS FOR HIEST POPS PEGGED SRN CWA THU NIGHT TO ERN CWA AT LEAST ERLY FRI. THEREAFTER...UNCERTAINTY REIGNS WITH PIN-POINT OF PSBL MCS TOPPING UPSTREAM LOW AMPED RIDGE TO LKLY REMAIN QUITE AN ONEROUS TASK. PREFERENCE TO REMAIN DRY DYS5-7 IN MIDST OF ONSET OF LOW END/ERLY STAGE DROUGHT UNTIL SIGNALS BECOME MORE EVIDENT.&& .AVIATION... GUSTY WINDS MAIN FACTOR NEXT COUPLE OF HOURS WITH PRE FRONTAL TROUGH AND COLD FRONT TO PROVIDE POSSIBLE FOCI FOR STORMS LATER THIS AFTERNOON INTO TONIGHT. CHANCES OF DEVELOPMENT AND COVERAGE STILL LOW...SO HAVE MAINTAINED VCTS UNTIL CLEARER SIGNALS APPEAR. WINDS WILL SHIFT OVERNIGHT INTO TUESDAY MORNING WITH COOLER AIR ARRIVING. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR INZ007>009-017-018- 023>027-032>034. MI...NONE. OH...HEAT ADVISORY UNTIL 7 PM EDT THIS EVENING FOR OHZ001-002-004-005- 015-016-024-025. LM...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR LMZ043-046. && $$ SHORT TERM...FISHER LONG TERM...MURPHY AVIATION...FISHER
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1233 PM CDT MON MAY 28 2012 .AVIATION... A BROAD AND DIFFUSE COOL FRONT WILL PASS ACROSS THE AREA THE NEXT 3-6 HOURS. THIS MAY RESULT IN ISOLATED TO SCATTERED...HIGHER BASED SHOWERS AND THUNDERSTORMS. THE PROBABILITY OF PRECIPITATION AFFECTING ANY TERMINAL IS TOO LOW TO PUT IN ANY TERMINAL AREA FORECAST. ANY STORM THAT OCCURS OVER A TERMINAL MAY CAUSE A BRIEF PERIOD OF MVFR CONDITIONS. SOUTHWEST WINDS OF 15 TO 25 MPH WILL SHIFT TO THE WEST AND DECREASE TO 5 TO 15 MPH BY 29/00Z. CLEAR TO MOSTLY CLEAR SKIES WILL THEN PERSIST THROUGH TUESDAY. VFR CONDITIONS WILL LAST FOR AT LEAST THE NEXT 24 HOURS....PROBABLY MUCH LONGER. NICHOLS && .PREV DISCUSSION... /ISSUED 645 AM CDT MON MAY 28 2012/ UPDATE... LATEST RADAR LOOP SHOWED A LINE OF ELEVATED SHOWERS AND A FEW THUNDERSTORMS REACHING FROM MANCHESTER THROUGH CEDAR RAPIDS TO JUST WEST OF FAIRFIELD WITH A SECOND LINE FROM WATERLOO TO CENTERVILLE. THESE SHOULD CONTINUE TO WEAKEN WITH THE DIURNAL WANING OF THE LOW LEVEL JET AND ASSOCIATED THETEA ADVECTION. HOWEVER...WITH SUPPORT FROM A DISTINCT MID LEVEL SHORTWAVE AND DRY SLOT LIFTING INTO SE AND EAST CENTRAL IA...WILL EXPECT AT LEAST A COUPLE MORE HOURS OF WEAKENING SHOWERS AND AT LEAST ISOLATED THUNDERSTORMS TO OVERSPREAD EASTERN IA INTO FAR NW IL. LATEST RAP AND HRRR HIGH RES MODELS GENERALLY SUGGEST THIS. THE LIMITED COVERAGE APPEARS TO BE HANDLED BY THE CHANCE POPS IN THE FORECAST FOR THIS MORNING. WILL CONTINUE TO REEVALUATE THE POTENTIAL FOR NEW CONVECTION ALONG THE ADVANCING SURFACE BOUNDARY IN WESTERN IA WITH THE NEW UPPER AIR DATA AND MODEL RUNS THIS MORNING. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ NICHOLS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
348 PM CDT MON MAY 28 2012 ...UPDATED FOR LONG TERM DISCUSSION... .SYNOPSIS... ISSUED AT 313 PM CDT MON MAY 28 2012 THE MAIN SYNOPTIC FEATURE ACROSS THE CONUS WAS A MID-LATITUDE CYCLONE SPINNING OVER WESTERN NORTH DAKOTA EARLY THIS AFTERNOON. AN UPPER TROPOSPHERIC JET STREAK EXTENDED FROM THE CENTRAL COLORADO ROCKIES NORTHEASTWARD TO LAKE SUPERIOR WITH ABOUT A 90-100 KNOT JET STREAK WITHIN THE CORE OVER SOUTHERN MINNESOTA PER RAP ANALYSIS. THE POLAR FRONT AT THE SURFACE TIED TO THIS STORM SYSTEM HAD PUSHED ALL THE WAY INTO SOUTHWEST OKLAHOMA WHERE IT HAD STALLED OUT AND LOST DEFINITION. THE SURFACE HIGH BEHIND THE FRONT WAS CENTERED OVER THE NORTHWESTERN PORTION OF KANSAS...BUT THE HIGH WAS QUITE WEAK WITH ONLY A 1012MB CENTER. RICH GULF OF MEXICO MOISTURE CONTINUED TO POOL ALONG AND JUST SOUTH OF THE DECAYING FRONT IN NORTHWEST TEXAS WHERE 850MB DEWPOINTS WERE 15 TO 18C (DEWPOINT +17C AT KMAF AND KOUN ON THE 12Z RAOB). A SUBTROPICAL JET WAS ALSO ANALYZED FROM NORTHERN BAJA CALIFORNIA EAST-NORTHEASTWARD TO SOUTHERN NEW MEXICO. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 313 PM CDT MON MAY 28 2012 TONIGHT: THE SURFACE HIGH TO THE NORTH WILL CONTINUE TO WEAKEN AND LOSE ITS GRIP WITH POST FRONTAL WINDS BECOMING INCREASINGLY EASTERLY LATE TONIGHT. THE DRY AIRMASS COMBINED WITH CLEAR SKIES SHOULD RESULT IN A GOOD RADIATIONAL COOLING ENVIRONMENT ALLOWING TEMPERATURES TO FALL INTO THE MID 50S FOR OVERNIGHT LOWS. MEANWHILE...A SURFACE LOW WILL SLOWLY DEVELOP ACROSS WEST TEXAS WITH A MESOSCALE CONVECTIVE SYSTEM LIKELY AFFECTING AREAS WELL SOUTH OF SOUTHWEST KANSAS ALONG THE RED RIVER VALLEY. TOMORROW: WARM/MOIST ADVECTION IN THE 850-750MB LAYER WILL INCREASE 12-18Z ACROSS SOUTH CENTRAL KANSAS WITH ELEVATED CONVECTION EXPECTED TO FORM. BOTH THE NAM AND THE GFS MODELS SUGGEST THIS IN THE CONVECTIVE QPF FIELD AND MAKES REASONABLE SENSE...CONSIDERING THIS AREA WOULD BE IN THE LEFT EXIT REGION OF THE INCOMING SUBTROPICAL JET. WILL INCREASE THE POPS TO 20-35 PERCENT AND BEGIN THEM EARLIER IN THE SOUTHEASTERN COUNTIES. WILL HAVE TO WATCH OUT FOR SOME SEVERE HAIL DURING THE 12-18Z TIME FRAME AS MOST-UNSTABLE CAPE WILL BE QUITE HIGH (2000-3000 J/KG) GIVEN THE MOISTURE CONTENT MOVING BACK NORTH INTO SOUTHERN KANSAS. SHOULD THESE STORMS MATERIALIZE...THEN THEY WILL LIKELY LEAVE AN OUTFLOW BOUNDARY FOR EVEN MORE ROBUST SURFACE-BASED CONVECTION LATER ON IN THE AFTERNOON AFFECTING AREAS MAINLY NEAR THE OKLAHOMA BORDER. WILL MAINTAIN THE CHANCE POPS THROUGH 00Z. BECAUSE OF THE MORNING CONVECTION POSSIBILITY AND OUTFLOW BOUNDARY(IES)...TEMPERATURES WILL BE A CHALLENGE GIVEN UNCERTAIN AMOUNTS OF CLOUD COVER AND THE COLD POOL IN THE WAKE OF ANY STORMS. WILL KEEP THE TEMPERATURE FORECAST UNCHANGED FOR NOW WITH WIDESPREAD MID TO UPPER 80S EXPECTED ACROSS THE SOUTHWEST KANSAS REGION. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 343 PM CDT MON MAY 28 2012 A STRONG SHORTWAVE TROUGH THAT PROGRESSED ACROSS THE NORTHERN PLAINS TODAY HAS PUSHED A COLD FRONT THROUGH KANSAS. HOWEVER, THE MID- LEVEL FLOW ACROSS THE SOUTHERN ROCKIES IS STILL STRONGLY ZONAL, SO IT IS ONLY A MATTER OF TIME BEFORE LEE TROUGHING DEVELOPS ACROSS THE SOUTHERN PLAINS. TWO UPPER-LEVEL SYSTEMS WILL BE AFFECTING THE CENTRAL AND SOUTHERN PLAINS THROUGH WEDNESDAY. ONE SYSTEM WAS APPROACHING THE NORTHWESTERN COAST THIS AFTERNOON AND THE OTHER WAS JUST OFF THE SOUTHERN CALIFORNIA COAST. BY WEDNESDAY, THESE SYSTEMS WILL BE APPROACHING THE HIGH PLAINS. THE SOUTHERN SYSTEM WILL RESULT IN SURFACE PRESSURE FALLS ACROSS NORTHERN TEXAS, BUT AN INVERTED TROUGH IS PROGGED TO EXTEND NORTHWARD FROM THIS LOW AS PRESSURES FALL IN THE LEE OF THE CENTRAL ROCKIES UPON THE APPROACH OF THE NORTHERN SHORTWAVE TROUGH. ABUNDANT LOW-LEVEL MOISTURE WILL MOVE NORTH INTO TEXAS, AND THEN ADVECT TO THE WEST AND NORTHWEST AROUND THE NORTH SIDE OF THE SOUTHERN PLAINS SURFACE LOW. THUNDERSTORMS ARE EXPECTED TO DEVELOP WEDNESDAY AFTERNOON ACROSS WESTERN KANSAS AND THEN PROGRESS INTO CENTRAL KANSAS WEDNESDAY EVENING. SOME OF THESE STORMS COULD BE SEVERE WITH LARGE HAIL. BEFORE STORMS DEVELOP WEDNESDAY AFTERNOON, THE ECMWF AND NAM INDICATE HIGHS MAINLY IN THE LOWER TO MID 80S. THE AFOREMENTIONED NORTHERN STREAM SHORTWAVE TROUGH WILL PASS ACROSS THE CENTRAL PLAINS WEDNESDAY NIGHT AND THURSDAY, PUSHING A COLD FRONT TROUGH WESTERN KANSAS. THUS, RAIN CHANCES WILL END LATE WEDNESDAY NIGHT. HIGHS WILL ONLY BE IN THE UPPER 60S TO MID 70S THURSDAY BEHIND THE FRONT. WEAK UPPER-LEVEL RIDGING WILL DEVELOP ACROSS THE ROCKIES BY FRIDAY. BUT THERE WILL BE A COMPONENT OF MID-LEVEL FLOW ACROSS THE ROCKIES, WHICH WILL TEND TO LOWER SURFACE PRESSURES AND BRING SOME LOW-LEVEL MOISTURE BACK INTO WESTERN KANSAS. TYPICALLY, MID-LEVEL CAPPING IS NOT VERY STRONG IN WEST-NORTHWESTERLY FLOW REGIMES. THUS, THUNDERSTORMS ARE POSSIBLE INTO SUNDAY AS THE RIDGE AXIS SLOWLY EDGES EASTWARD TOWARD THE HIGH PLAINS. ALTHOUGH HIGH-END SEVERE STORMS ARE NOT LIKELY IN THIS REGIME DUE TO LIMITED INSTABILITY, INDIVIDUAL STORM CLUSTERS COULD BRING A ROUND OR TWO OF MARGINALLY SEVERE STORMS. TEMPERATURES ARE HARD TO FORECAST FOR THIS TIME PERIOD SINCE ANY STORM CLUSTERS COULD RESULT IN COOLER TEMPERATURES ON ANY GIVEN DAY. BUT THERE SHOULD BE A GENERAL WARMING TREND FROM HIGHS IN THE 80S FRIDAY AND SATURDAY TO THE 90S BY SUNDAY. AFTER SUNDAY, A LOW AMPLITUDE UPPER-LEVEL TROUGH IS EXPECTED TO DEVELOP NEAR THE WEST COAST, WITH WEST-SOUTHWESTERLY FLOW ACROSS THE NORTHERN PLAINS. ORGANIZED THUNDERSTORM ACTIVITY DURING THIS TIME FRAME WILL LIKELY BE CLOSER TO THE JET STREAM TO OUR NORTH. HOWEVER, MORE ISOLATED ACTIVITY COULD DEVELOP FURTHER SOUTH AROUND THE PERIPHERY OF AN UPPER-LEVEL RIDGE AXIS. TEMPERATURES WILL BE RATHER HOT, WITH HIGHS IN THE 90S TO NEAR 100F. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 100 PM CDT MON MAY 28 2012 AS A SURFACE HIGH DRIFTS EAST-SOUTHEAST ACROSS NEBRASKA AND NORTHERN KANSAS...NORTH WINDS WILL CONTINUE TO DECREASE AND BECOME LIGHT AND VARIABLE THIS AFTERNOON...LASTING THROUGH MUCH OF THE NIGHT TONIGHT. LOW LEVEL GULF OF MEXICO MOISTURE WILL BEGIN TO ADVANCE NORTH TUESDAY MORNING APPROACHING FAR SOUTHWEST KANSAS. SOUTHERLY NEAR-SURFACE WINDS WILL HELP DRAW THIS MOISTURE NORTHWARD INTO SOUTHWEST KANSAS...WITH STRATUS POSSIBLY DEVELOPING IN THE EARLY MORNING HOURS. AT THIS TIME IT APPEARS THE STRATUS SHOULD REMAIN SOUTH OF GARDEN AND DODGE CITY...SO NO REDUCTION IN CEILING AND/OR VISIBILITY IS FORECAST THROUGH 18Z TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... DDC 56 85 60 87 / 10 20 10 50 GCK 53 81 59 86 / 10 10 10 50 EHA 53 85 57 86 / 0 10 10 30 LBL 55 86 59 87 / 10 10 10 40 HYS 53 81 58 85 / 10 20 20 40 P28 62 87 64 88 / 10 30 20 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...UMSCHEID SHORT TERM...UMSCHEID LONG TERM...FINCH AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
315 PM CDT MON MAY 28 2012 ...UPDATED SYNOPSIS AND SHORT TERM SECTIONS... .SYNOPSIS... ISSUED AT 313 PM CDT MON MAY 28 2012 THE MAIN SYNOPTIC FEATURE ACROSS THE CONUS WAS A MID-LATITUDE CYCLONE SPINNING OVER WESTERN NORTH DAKOTA EARLY THIS AFTERNOON. AN UPPER TROPOSPHERIC JET STREAK EXTENDED FROM THE CENTRAL COLORADO ROCKIES NORTHEASTWARD TO LAKE SUPERIOR WITH ABOUT A 90-100 KNOT JET STREAK WITHIN THE CORE OVER SOUTHERN MINNESOTA PER RAP ANALYSIS. THE POLAR FRONT AT THE SURFACE TIED TO THIS STORM SYSTEM HAD PUSHED ALL THE WAY INTO SOUTHWEST OKLAHOMA WHERE IT HAD STALLED OUT AND LOST DEFINITION. THE SURFACE HIGH BEHIND THE FRONT WAS CENTERED OVER THE NORTHWESTERN PORTION OF KANSAS...BUT THE HIGH WAS QUITE WEAK WITH ONLY A 1012MB CENTER. RICH GULF OF MEXICO MOISTURE CONTINUED TO POOL ALONG AND JUST SOUTH OF THE DECAYING FRONT IN NORTHWEST TEXAS WHERE 850MB DEWPOINTS WERE 15 TO 18C (DEWPOINT +17C AT KMAF AND KOUN ON THE 12Z RAOB). A SUBTROPICAL JET WAS ALSO ANALYZED FROM NORTHERN BAJA CALIFORNIA EAST-NORTHEASTWARD TO SOUTHERN NEW MEXICO. && .SHORT TERM...(THIS EVENING THROUGH TOMORROW) ISSUED AT 313 PM CDT MON MAY 28 2012 TONIGHT: THE SURFACE HIGH TO THE NORTH WILL CONTINUE TO WEAKEN AND LOSE ITS GRIP WITH POST FRONTAL WINDS BECOMING INCREASINGLY EASTERLY LATE TONIGHT. THE DRY AIRMASS COMBINED WITH CLEAR SKIES SHOULD RESULT IN A GOOD RADIATIONAL COOLING ENVIRONMENT ALLOWING TEMPERATURES TO FALL INTO THE MID 50S FOR OVERNIGHT LOWS. MEANWHILE...A SURFACE LOW WILL SLOWLY DEVELOP ACROSS WEST TEXAS WITH A MESOSCALE CONVECTIVE SYSTEM LIKELY AFFECTING AREAS WELL SOUTH OF SOUTHWEST KANSAS ALONG THE RED RIVER VALLEY. TOMORROW: WARM/MOIST ADVECTION IN THE 850-750MB LAYER WILL INCREASE 12-18Z ACROSS SOUTH CENTRAL KANSAS WITH ELEVATED CONVECTION EXPECTED TO FORM. BOTH THE NAM AND THE GFS MODELS SUGGEST THIS IN THE CONVECTIVE QPF FIELD AND MAKES REASONABLE SENSE...CONSIDERING THIS AREA WOULD BE IN THE LEFT EXIT REGION OF THE INCOMING SUBTROPICAL JET. WILL INCREASE THE POPS TO 20-35 PERCENT AND BEGIN THEM EARLIER IN THE SOUTHEASTERN COUNTIES. WILL HAVE TO WATCH OUT FOR SOME SEVERE HAIL DURING THE 12-18Z TIME FRAME AS MOST-UNSTABLE CAPE WILL BE QUITE HIGH (2000-3000 J/KG) GIVEN THE MOISTURE CONTENT MOVING BACK NORTH INTO SOUTHERN KANSAS. SHOULD THESE STORMS MATERIALIZE...THEN THEY WILL LIKELY LEAVE AN OUTFLOW BOUNDARY FOR EVEN MORE ROBUST SURFACE-BASED CONVECTION LATER ON IN THE AFTERNOON AFFECTING AREAS MAINLY NEAR THE OKLAHOMA BORDER. WILL MAINTAIN THE CHANCE POPS THROUGH 00Z. BECAUSE OF THE MORNING CONVECTION POSSIBILITY AND OUTFLOW BOUNDARY(IES)...TEMPERATURES WILL BE A CHALLENGE GIVEN UNCERTAIN AMOUNTS OF CLOUD COVER AND THE COLD POOL IN THE WAKE OF ANY STORMS. WILL KEEP THE TEMPERATURE FORECAST UNCHANGED FOR NOW WITH WIDESPREAD MID TO UPPER 80S EXPECTED ACROSS THE SOUTHWEST KANSAS REGION. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 352 AM CDT MON MAY 28 2012 WESTERN AND CENTRAL KANSAS WILL BE IN A TRANSITION PERIOD HEADING FROM TUESDAY INTO THE MIDDLE OF THE WEEK. THE SYNOPTIC PATTERN OF THE GLOBAL MODELS HAS THE CLOSED MONTANA LOW DRIFTING ACROSS THE NORTHERN PLAINS INTO THE FAR UPPER MIDWEST, WHILE A MID LEVEL POSITIVELY TILTED TROUGH IS DEVELOPING OVER THE DESERT SOUTHWEST. ON MONDAY NIGHT AND TUESDAY, THE WEAK HIGH PRESSURE OVER WESTERN KANSAS WILL BEGIN TO BECOME REPLACED BY AN INVERTED TROUGH OF LOW PRESSURE OVER THE TEXAS PANHANDLE THROUGH EXTREME SW KS AND SE COLORADO. AS A RESULT, A SOURCE OF LOW LEVEL BAROCLINICITY WILL DEVELOP SOMEWHERE IN THE CENTRAL HIGH PLAINS WHICH MIGHT BE A GOOD PORTION OF SOUTH WEST OR SOUTH CENTRAL KANSAS. ANY CONVECTION WOULD LIKELY BE DIURNAL IN NATURE, FOCUSED ON THE DEVELOPING FRONTAL BOUNDARY TUESDAY. FROM THIS POINT FOREWORD, MORE UNCERTAINTY EXISTS. FROM A MODEL STANDPOINT, GIVEN THE UPPER JET ADVANCING FROM THE NORTHWEST, AND BOUTS OF SHORTWAVE ENERGY INTO THE REGION, ORGANIZED CONVECTION APPEARS LIKELY ON WEDNESDAY AS WELL. THE GFS AND ECMWF PATTERNS BY WEDNESDAY NIGHT SEEM TO SUPPORT A LONG LIVED MCS ACROSS KANSAS AND OKLAHOMA. THE POTENTIAL FOR SURFACE BASED SUPERCELL DEVELOPMENT ALONG A STATIONARY BOUNDARY FOLLOWED BY A SEVERE HAIL AND HEAVY RAIN PRODUCING MCS WEDNESDAY EVENING/OVERNIGHT SEEMS PLAUSIBLE. THE REMAINDER OF THE EXTENDED FORECAST PERIOD SHOULD BE FAR LESS ACTIVE. THE UPPER JET POSITION AND RIDGING PATTERN SHOULD LEAVE WESTERN KANSAS MOSTLY DRY, WITHOUT ANY SIGNIFICANT PRECIPITATION. THERE COULD BE A DIRTY HIGH PRESSURE LEFT OVER THROUGH FRIDAY, ESPECIALLY IF A LARGE AMOUNT OF PRECIPITATION OCCURS WEDNESDAY INTO EARLY THURSDAY. FOG OVERNIGHT, AND LOW CLOUDS IN THE DAYTIME HOURS ON THURSDAY OR THURSDAY NIGHT WOULD BE DIFFICULT TO FORECAST WITH ANY CONFIDENCE AT THIS POINT, BUT SOMETHING TO WATCH FUTURE MODEL RUNS FOR. IT WOULD ALSO HAVE A MAJOR IMPACT ON MAX AND MINIMUM TEMPERATURES LATE IN THE WEEK. AS A FLAT RIDGE DEVELOPS ALOFT INTO THE WEEKEND HIGHS TEMPERATURES TREND THROUGH THE UPPER 80S BY FRIDAY AND SATURDAY; A SETUP FAVORABLE FOR TYPICAL HIGHER TERRAIN HIGH PLAINS THUNDERSTORMS ANY GIVEN EVENING. OVERNIGHT LOWS WILL TREND UPWARD AS WELL THROUGH THE PERIOD WITH INCREASING THICKNESS PATTERNS; FROM THE 50S THROUGH THE MIDDLE 60`S BY LATE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 100 PM CDT MON MAY 28 2012 AS A SURFACE HIGH DRIFTS EAST-SOUTHEAST ACROSS NEBRASKA AND NORTHERN KANSAS...NORTH WINDS WILL CONTINUE TO DECREASE AND BECOME LIGHT AND VARIABLE THIS AFTERNOON...LASTING THROUGH MUCH OF THE NIGHT TONIGHT. LOW LEVEL GULF OF MEXICO MOISTURE WILL BEGIN TO ADVANCE NORTH TUESDAY MORNING APPROACHING FAR SOUTHWEST KANSAS. SOUTHERLY NEAR-SURFACE WINDS WILL HELP DRAW THIS MOISTURE NORTHWARD INTO SOUTHWEST KANSAS...WITH STRATUS POSSIBLY DEVELOPING IN THE EARLY MORNING HOURS. AT THIS TIME IT APPEARS THE STRATUS SHOULD REMAIN SOUTH OF GARDEN AND DODGE CITY...SO NO REDUCTION IN CEILING AND/OR VISIBILITY IS FORECAST THROUGH 18Z TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... DDC 56 85 60 87 / 10 20 10 50 GCK 53 81 59 86 / 10 10 10 50 EHA 53 85 57 86 / 0 10 10 30 LBL 55 86 59 87 / 10 10 10 40 HYS 53 81 58 85 / 10 20 20 40 P28 62 87 64 88 / 10 30 20 40 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...UMSCHEID SHORT TERM...UMSCHEID LONG TERM...RUSSELL AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
451 PM EDT MON MAY 28 2012 .SYNOPSIS... ISSUED AT 450 PM EDT MON MAY 28 2012 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL LOW OVER NW NORTH DAKOTA RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE NRN GREAT LAKES. AT THE SFC...A BROAD AREA OF LOW PRES EXTENDED FROM SE MANITOBA TO LAKE SUPERIOR WITH A COLD FRONT EXTENDING FROM CNTRL LAKE SUPERIOR INTO CNTRL WI AND ERN IA. CLUSTERS OF STRONG TSRA HAVE DEVELOPED AHEAD OF THE COLD FRONT OVER NE WI INTO S CNTRL UPPER MI WHERE A SVR WATCH HAS BEEN ISSUED. LAKE BREEZE BOUNDARIES OFF OF LAKE SUPERIOR HAVE PUSHED QUICKLY THROUGH NW AND N CNTRL UPPER MI. ADDITIONAL TSRA HAD DEVELOPED ALONG AND OVER THE LK BREEZE AND MOVED THROUGH N CNTRL UPPER MI INTO LAKE SUPERIOR. ANOTHER AREA OF TSRA HAD DEVELOPED FROM DLH TO STC AHEAD OF A TRAILING SHRTWV TROUGH. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 450 PM EDT MON MAY 28 2012 LATE THIS AFTERNOON AND TONIGHT...WITH SBCAPE VALUES INTO THE 1000-1500 J/KG RANGE AHEAD OF NE MOVING SHRA/TSRA...EXPECT CONTINUING SVR POTENTIAL FROM ESC TO ERY THROUGH 00Z. THE MAIN HAZARD WILL CONTINUE TO BE DAMAGING WIND GUSTS. EXPECT THE SHRA/TSRA OVER THE EAST HALF TO DIMINISH/END OVER THE CNTRL/EAST LATER THIS EVENING AS THE INITIAL FRONT/TROUGH MOVES THROUGH THE AREA AND SLIGHTLY DRIER AIR MOVES IN. HOWEVER...PER RADAR/SATELLITE TRENDS EXPECT SCT SHRA/TSRA TO MOVE INTO THE WRN CWA LATER THIS EVENING AND LIFT OVER LAKE SUPERIOR LATE TONIGHT. TUESDAY...GOING FCST LOOKS ON TRACK WITH THICKENING CLOUDS AND INCREASING SCT INSTABILITY SHRA BY AFTN AS THE MID/UPPER TROUGH AXIS SETTLES CLOSE BY. HINT OF ANOTHER SHORTWAVE TROUGH ROTATING THROUGH SHOULD ALSO BOOST SHRA CHANCES. WITH VERY LIMITED INSTABILITY (SBCAPE VALUES AOB 200 J/KG) EXPECTED...NO TSRA WERE MENTIONED AT THIS TIME. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 450 PM EDT MON MAY 28 2012 TUES NIGHT THROUGH THURSDAY...SHOWERS SHOULD DEVELOP TUES AFTN ASSOCIATED WITH STEEP LLVL LAPSE RATES AND SHORTWAVE ROTATING THROUGH. EXPECT THESE SHOWERS TO DIMINISH TOWARDS THE START OF THE PERIOD...ESPECIALLY OVER THE ERN CWA AS MUCH OF THE UPPER LEVEL DYNAMICS SHIFT TO THE NE OF THE CWA. WITH THAT BEING SAID...EXPECT SCATTERED SHOWERS TO LINGER OVER THE WRN THIRD OF THE CWA DURING THE EVENING AS THE SFC TROUGH SLIDES S ACROSS THE AREA. THE WRN THIRD WILL BE UNDER THE STRONGER FORCING FROM THE H925-850 TROUGH AND DEEPER MOISTURE. THUS...HAVE BUMPED POPS UP TO CHANCES AND LINGERED THROUGH MUCH OF THE NIGHT OVER THE FAVORED HIGHER TERRAIN LOCATIONS FAVORED BY NW WINDS. HIGH RES MODEL RUNS PICK UP ON THIS FAIRLY WELL AND HAVE FOLLOWED THE TRENDS...ALTHOUGH POPS MAY END UP NEEDING TO BUMPED UP FURTHER. HAVE PUT SLIGHT POPS IN FARTHER EAST NEAR LK SUPERIOR DURING THE OVERNIGHT HOURS DUE TO THE LIGHT UPSLOPE FLOW AND FRICTIONAL CONVERGENCE. EXPECT THESE SHOWERS TO TO LINGER INTO THE FIRST PART OF WED MORNING...BEFORE DRIER AIR ARRIVES. UPPER TROUGH OVER ERN CANADA WILL PIVOT THROUGH ON WED...WHILE SFC HIGH PRESSURE MOVES OVER THE AREA ON WED AND REMAINS THROUGH THURS. THE DRIER AIR WITH THE HIGH PRESSURE WILL LEAD TO DECREASING CLOUDS FROM WEST TO EAST FROM MID MORNING ON. SHOULD SEE SOME SCT CLOUDS REDEVELOP WITH LINGERING MOISTURE AND DIURNAL HEATING AWAY FROM LK SUPERIOR BUT THEN DIMINISH WITH THE INCREASING DRY AIR. FAIRLY COLD CANADIAN AIR ALOFT WITH H850 TEMPS AROUND -2C OVER THE AREA AROUND MID DAY THEN GRADUALLY WARM INTO THE LOWER SINGLE DIGITS IN THE AFTN. THIS SHOULD LEAD TO WELL BELOW NORMAL HIGHS ACROSS THE AREA ON WED. DID TWEAK TEMPS UP SLIGHTLY FROM THE GOING FORECAST OVER THE INTERIOR W WHERE THE MOST SUN WILL LIKELY BE HAD. MEANWHILE...COOL NNW FLOW OFF LK SUPERIOR WILL CAUSE TEMPS TO STRUGGLE TO REACH 50 FROM MARQUETTE EASTWARD ALONG THE SHORELINE. LOOKS LIKE A GOOD POTENTIAL OF FROST ON WED NIGHT UNDER MOSTLY CLEAR SKIES. PWATS ARE AROUND 30 PERCENT OF NORMAL...LIGHT WINDS UNDER THE HIGH...AND COOL DAYTIME TEMPS ON WED SHOULD LEAD TO A COLD NIGHT ACROSS THE CWA. EXPECT TEMPS TO FALL INTO THE UPPER 20S AND LOWER 30S AWAY FROM THE GREAT LKS. DID BUMP UP FROST MENTION TO AREAS OVER THE INTERIOR WEST AND PORTIONS OF THE EAST. SHORTWAVE MOVING OUT OF THE ROCKIES ON WED NIGHT WILL AMPLIFY AN UPPER WAVE OVER THE PLAINS STATES ON THURS AND LEAD TO A LOW DEVELOPING OVER THE CNTRL/SRN PLAINS. NAM/GFS HINTING AT SOME DIURNAL CU DEVELOPING OVER INLAND AREAS ON THURS...ESPECIALLY ALONG THE LK BREEZE AREAS AND DID TRY TO SHOW SOME INCREASED CLOUD COVER IN THOSE AREAS. OTHERWISE...HIGH PRESSURE WILL BE IN CONTROL AND LEAD TO LK BREEZES DEVELOPING OFF BOTH LK SUPERIOR/MI. FOR THE EXTENDED /THURSDAY NIGHT THROUGH NEXT MONDAY/... EXTENDED FORECAST LOOKS TO BE MORE SIMILAR TO LATE WINTER AND EARLY SPRING THAN THE FIRST PART OF JUNE. LOW DEVELOPING IN THE CNTRL/SRN PLAINS ON THURS WILL MOVE NE THROUGH THE OHIO RIVER VALLEY ON FRIDAY AND THE EASTERN GREAT LKS ON SAT. 00Z ECMWF NOT AS WRAPPED UP AND FARTHER N THAN 00Z GEM/GFS. AFTER LOOKING AT THEIR ENS MEANS...A GENERAL CONSENSUS SEEMS REASONABLE AND WILL FOLLOW THAT FOR THE MOVEMENT OF THE LOW. THIS TRACK WILL BRUSH THE CWA AND COULD SEE SOME SHOWERS OVER THE ERN PART OF THE CWA ON FRI NIGHT...BUT MAINLY EXPECT MID-HIGH CLOUDS OVER MUCH OF THE CWA. SFC RIDGE WILL MOVE OVER THE CWA ON SUN IN ASSOCIATION WITH HIGH PRESSURE OVER THE CNTRL PLAINS AND BUILDING UPPER RIDGE OVER THE CNTRL CONUS. THIS RIDGE WILL SHIFT E ON MON AS SFC LOW DROPS OUT OF THE CANADIAN ROCKIES AND COLD FRONT MOVES THROUGH THE DAKOTAS. 12Z GFS HAS PUSHED THIS THROUGH MUCH FASTER AND WILL FOLLOW MORE CONSISTENT ECMWF. IT SHOWS H850-700 Q-VECTOR CONV AND MOISTURE MOVING THROUGH MON...WHICH WARRANTS MENTIONING A CHANCE OF PCPN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 125 PM EDT MON MAY 28 2012 KCMX...A PERIOD OF IFR CIGS WILL GIVE WAY TO MAINLY VFR CONDITIONS LATER THIS AFTERNOON AS DRIER AIR MOVES IN WITH WRLY FLOW. LIFR FOG/STRATUS AND ISOLD SHRA COULD REDEVELOP BY LATE EVENING WITH A SHRORTWAVE TROUGH BRUSHING THE AREA IN A WESTERLY FLOW BEFORE LIFTING LATE TONIGHT AS DRIER AIR MOVES IN FROM THE WEST. KIWD...EXPECT VFR CONDITIONS TO PREVAIL THROUGH MUCH OF THE PERIOD IN A PREVAILING WSW FLOW. THERE IS A SMALL CHANCE FOR SHOWERS EARLY THIS EVENING AS A SECONDARY TROUGH/FRONT MOVES THROUGH WITH DRY CONDITIONS EXPECTED BEHIND IT FOR THE OVERNIGHT HOURS. KSAW...LOOK FOR MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD. THERE IS A CHC FOR TSRA EARLY TO LATE AFTERNOON AS A SFC TROUGH MOVES INTO THE AREA. OTHERWISE...DRIER WRLY FLOW WILL BE UNFAVORABLE FOR DEVELOPMENT OF ANY CIGS BLO VFR. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 450 PM EDT MON MAY 28 2012(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 532 AM EDT MON MAY 28 2012 EXPECT WINDS TO SHIFT SOUTHWEST TO WEST WINDS TO 25 KTS IN THE WAKE OF A TROUGH/FRONTAL PASSAGE...ESPECIALLY OVR WRN AND NCNTRL LAKE SUPERIOR AROUND ISLE ROYALE AND THE KEWEENAW PENINSULA. WINDS VEERING NORTHWEST TUE NIGHT BEHIND A SECONDARY COLD FRONT COULD THEN REMAIN GUSTY TO NEAR 30 KTS OVER EASTERN LK SUPERIOR TUE NIGHT INTO WEDNESDAY MORNING. WINDS WILL DIMINISH LATER WEDNESDAY AS HIGH PRESSURE BUILDS BACK OVER THE AREA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SYNOPSIS...JLB SHORT TERM...JLB LONG TERM...TITUS AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
1251 PM CDT MON MAY 28 2012 .AVIATION...18Z TAFS. BULK OF THE CIGS HAVE IMPROVED TO VFR. INVOF STORMS...GUSTY SFC WINDS...SOME HAIL POSSIBLE. EXPECT STORMS TO EVOLVE THROUGH THE AFTERNOON AND AFFECT KBRD/KDLH/KHYR THROUGH 00Z/29. AFTER 00Z...VFR UNTIL 12Z-15Z WHEN MVFR CIGS AND GUSTY SFC WINDS WILL DEVELOP IN RESPONSE TO UPPER LOW MOVE ALONG THE INTERNATIONAL BORDER WITH ADDITIONAL SHOWERS POSSIBLE. && .PREV DISCUSSION... /ISSUED 1050 AM CDT MON MAY 28 2012/ UPDATE... LACKING SOME CONFIDENCE IN THE FORECAST TODAY DUE TO THE WIDESPREAD OVC STRATUS AND SOME DENSE FOG THAT DEVELOPED THIS MORNING ACROSS MUCH OF THE CENTRAL AND EASTERN FA. TEMPERATURES...SKY COVER...AND POSSIBLE AFTERNOON/EVENING THUNDERSTORMS WILL BE AFFECTED BY HOW QUICKLY THE STRATUS CAN LIFT AND CLEAR UP TODAY. THE MODELS STILL SUGGEST WESTERLY WINDS WILL DEVELOP LATER THIS MORNING...AND IT DOES APPEAR THAT THEY ARE BEGINNING TO IN THE AREAS OF THE STRATUS. THEREFORE...ONLY SLIGHTLY DECREASED THE HIGH TEMPERATURES IN THE AREAS THAT HAD THE STRATUS THIS MORNING...AND WILL STILL EXPECT MORE RAPID WARMING THIS AFTERNOON WHEN THERE IS SOME CLEARING. WILL CONTINUE TO COVER THE FOG WITH NOWCASTS IF THE FOG PERSISTS PAST NOON. STORM PREDICTION CENTER REVISED THEIR DAY 1 SLIGHT RISK OF SEVERE WEATHER...WHICH HAD PREVIOUSLY ONLY SKIRTED OUR FAR SE FA...TO NOW INCLUDE MUCH OF THE SOUTHERN FA. THIS DOES SEEM PLAUSIBLE CONSIDERING THE MODELS SUGGEST SURFACE AND ML CAPE OF 500 TO 1500 J/KG DEVELOPING THIS AFTERNOON ACROSS THE SOUTHERN FA. THE NAME INDICATES DEEP LAYER SHEAR (0-6 KM) WILL BE ABOUT 30 TO 40 KNOTS...SO THERE COULD BE SOME ORGANIZATION TO THE STORMS. THE MAIN THREATS SHOULD BE HAIL...WIND...AND BRIEF HEAVY RAIN. THINK IT WILL DEPEND ON HOW MUCH CLEARING THERE IS THIS AFTERNOON TO BUILD UP THE INSTABILITY. THE WRF AND HRRR RUNS HAVE INDICATED A BAND OF SHOWERS/STORMS MOVING INTO THE WESTERN FA MID TO LATE AFTERNOON...AND THEN MOVING INTO THE CENTRAL AND EASTERN FA INTO THIS EVENING. HYDROLOGY... ELEVATED WATER LEVELS ARE OCCURRING OR FORECASTED ALONG SEVERAL RIVER FORECAST LOCATIONS IN THE NORTHLAND...AND FOLLOWUP STATEMENTS WERE ISSUED THIS MORNING. ALLOWED SOME AREAL FLOOD WARNINGS FOR PORTIONS OF EAST CENTRAL MINNESOTA TO EXPIRE...BUT CONTINUED AN URBAN AND SMALL STREAM ADVISORY DUE TO EMERGENCY MANAGERS REPORTING SOME FLOODED ROADS IN CROW WING AND AITKIN COUNTIES. WILL LOOK MORE INTO THE NEED TO CONTINUE THE AREAL FLOOD WARNINGS IN THE SOUTH CENTRAL FA THIS AFTERNOON. PREV DISCUSSION... /ISSUED 626 AM CDT MON MAY 28 2012/ AVIATION...12Z TAFS RAIN WAS DIMINISHING ACROSS THE NORTHLAND THIS MORNING...WITH IFR CONDITIONS ACROSS THE NORTH...AND SOME PATCHY IFR CONDITIONS SOUTH AS WELL. WEST-SOUTHWEST WINDS WILL DEVELOP TODAY...AND SHOULD SCOUR OUT MUCH OF THE IFR CONDITIONS. HOWEVER...COLDER TEMPS ALOFT WILL LEAD TO A CUMULUS DECK...WITH LOW VFR OR MVFR CEILINGS RESULTING. SOME SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE...MAINLY THIS AFTERNOON AND EARLY EVENING. MVFR WITH POCKETS OF IFR CEILINGS WILL OCCUR/MOVE IN TONIGHT WITH THE UPPER TROUGH OVERHEAD. PREV DISCUSSION... /ISSUED 606 AM CDT MON MAY 28 2012/ UPDATE... CANCELED THE FLASH FLOOD WATCH AS THE HEAVY RAIN HAS DISSIPATED ACROSS THE AREA AND THE MAIN THREAT FOR WIDESPREAD FLASH FLOODING HAS ENDED THIS MORNING. ALSO ADDED PATCHY DENSE FOG TO THE FORECAST FOR THIS MORNING. WAS ON THE FENCE CONCERNING A DENSE FOG ADVISORY. HOWEVER THE NEXT COUPLE HOURS OF RECENT RAP MODEL RUNS CONSISTENTLY INDICATE THE FOG SHOULD LIFT AND DISSIPATE AS THE SW WINDS RAMP UP AND MIX OUT THE LOW LEVEL MOISTURE FAIRLY RAPIDLY. SHOULD SEE MOST OF THE FOG LIFT BY 8-9 AM THIS MORNING. PREV DISCUSSION... /ISSUED 322 AM CDT MON MAY 28 2012/ SHORT TERM... TODAY THROUGH TUESDAY AFTERNOON... MAIN CHALLENGES IN THE SHORT TERM ARE FOCUSED AROUND THE SHOWERS AND STORMS MOVING NWD THROUGH THE REGION THIS MORNING...WITH THE POTENTIAL FOR ADDITIONAL LOCALIZED FLOODING...AND THEN ANOTHER ROUND OF SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING OVER N-CENTRAL MN AND MOVING EWD THROUGH THE NORTHLAND THIS AFTERNOON AND EVENING. WILL ALSO SEE ADDITIONAL CHANCES FOR COOL RAIN SHOWERS ACROSS THE FORECAST AREA TONIGHT AND THROUGH THE DAY TUESDAY. AN ARRAY OF FLOOD PRODUCTS ARE CURRENTLY IN EFFECT THIS MORNING...THROUGH THE DAY TODAY...MAINLY ACROSS THE SOUTHERN/SWRN COUNTIES OF THE NORTHLAND...WHICH HAVE RECEIVED THE MOST RAIN THROUGH THE LAST COUPLE DAYS. AS OF 3 AM THIS MORNING...HAVE ALREADY SEEN THE HEAVIEST RAIN SHOWERS WEAKEN AND LIFT TO THE NORTH...WITH SIGNIFICANT DIMINISHING OF THUNDERSTORMS ACROSS SRN MN AS WELL. AT THIS POINT...NOT EXPECTING TO SEE THE VERY HEAVY RAINFALL SEEN EARLIER TONIGHT AND LAST NIGHT THIS MORNING...SHOULD MAINLY BE LIGHT TO OCCASIONALLY MDT SHOWERS AND ISOLATED T-STORMS THROUGH THE REST OF TODAY. THERE IS CURRENTLY A NARROW AXIS OF 700MB F-GEN SITUATED ACROSS SWRN MN/NWRN IA...THAT IS PROGGED TO LIFT NWD INTO NE MN THIS MORNING. THERE IS THE POSSIBILITY THAT ADDITIONAL SIGNIFICANT RAINFALL COULD DEVELOP ASSOCIATED WITH THIS F-GEN BAND. SO...AT THIS TIME WILL CONTINUE WITH THE BROAD FLASH FLOOD WATCH THROUGH 7 AM THIS MORNING...AND RE-EVALUATE THE SITUATION PRIOR TO EITHER CANCELING OR EXTENDING THE WATCH THIS MORNING. SYNOPTIC SET UP SHOWS THE UPPER LOW LIFTING NWD INTO SRN MANITOBA THIS MORNING AS THE ELONGATED SFC TROUGH/COLD FRONT CONTINUES TO MOVE E/NEWD THROUGH CENTRAL/ERN MN. THERE IS A SECONDARY SFC LOW CO-LOCATED WITH THE UPPER LOW THAT WILL EVENTUALLY MOVE EWD ACROSS ND TODAY AND TONIGHT...AND AID IN THE RE-ENFORCEMENT OF ADDITIONAL SHOWERS AND THUNDERSTORMS TODAY...AND MAINLY SHOWERS TONIGHT. IT APPEARS THAT THERE WILL BE ENOUGH LINGERING INSTABILITY COMBINED WITH SLIGHTLY COOLER TEMPERATURES ALOFT AND WARM SFC TEMPS TO STEEPEN LAPSE RATES ENOUGH TO TRIGGER SCATTERED SHOWERS AND T-STORMS THIS AFTERNOON. ALTHOUGH SHOULD SEE A RAPID DECREASE IN ACTIVITY CLOSER TO SUNSET AS THE BNDY LAYER BECOMES MORE STABLE. THE UPPER LOW WILL LAG SLIGHTLY BEHIND THE EWD MOVEMENT OF THE SECONDARY SFC LOW TOMORROW...AND HAVE NOTICEABLY COOLER AIR ASSOCIATED WITH IT. WHILE MUCH OF THE NORTHLAND TODAY WILL SEE WINDS SHIFT TO THE SW AND TEMPERATURES CLIMB INTO THE UPPER 60S NORTH AND 70S TO THE SOUTH...TUESDAY WILL BE A MUCH DIFFERENT STORY AS A COLD AIR MASS BLASTS IN FROM THE NW. A RATHER COOL...IF NOT COLD LATE SPRING DAY IS IN STORE TUESDAY WITH HIGHS ONLY INTO THE UPPER 40S AND LOWER 50S ACROSS MUCH OF THE REGION AND A FEW LOWER 60S INTO NRN WI. THE STIFF NW WINDS AND CLOUDY SKIES WILL MAKE IT FEEL EVEN COLDER THAN THAT AT TIMES. LONG TERM... TUESDAY NIGHT THROUGH SUNDAY... PORTIONS OF OUR EASTERN CWA WILL STILL BE INFLUENCED BY AN UPPER TROUGH TUESDAY NIGHT ALONG WITH COLD TEMPERATURES. BOTH THE GFS AND ECMWF FORECAST 850MB TEMPS OF ZERO TO -3C OVER OUR CWA TUESDAY NIGHT. SOME LIGHT RAIN WILL BE POSSIBLE OVER THE EASTERN ZONES TUESDAY NIGHT...AND BOUNDARY LAYER TEMPS SHOULD BE TOO WARM FOR ANY SNOW TO MIX IN. HIGH PRESSURE NOSES INTO THE CWA WEDNESDAY AND IT SHOULD BE DRY. THE MODELS DIVERGE WEDNESDAY NIGHT INTO THURSDAY IN THE WAY THEY HANDLE AN UPPER LOW. THE ECMWF IS MUCH FURTHER NORTH THAN THE GFS. THE ECMWF HAS THE LOW OVER MINNESOTA...VERSUS THE GFS WHICH DIVES IT WELL SOUTH TO WHERE NE/IA/KS/MO MEET. WE WENT DRY WEDNESDAY NIGHT...BUT INTRODUCED SOME SMALL POPS FOR THURSDAY ACROSS THE SOUTH...WHICH IS CLOSER TO THE ECMWF. AFTER THE UPPER LOW SLIDES EAST...THE REGION GETS INTO NORTHWEST FLOW ALOFT FOR FRIDAY THROUGH SUNDAY WITH A COUPLE SHORTWAVES MOVING THROUGH BRINGING PERIODIC CHANCES FOR LIGHT RAIN. LOW PRESSURE WILL BE MOVING INTO THE NORTHERN PLAINS SUNDAY...AND WARM AIR ADVECTION AHEAD THIS SYSTEM AND A SHORTWAVE WILL BRING A BETTER CHANCE FOR SHOWERS/STORMS INTO THE CWA SUNDAY. TEMPERATURES WILL START QUITE COOL WITH SOME AREAS TUESDAY NIGHT DROPPING TO NEAR FREEZING. HIGHS WEDNESDAY IN THE MID FIFTIES TO AROUND SIXTY WILL INTO THE LOWER TO MID SEVENTIES BY NEXT SUNDAY. && .POINT TEMPS/POPS... DLH 47 54 38 58 / 30 30 10 10 INL 43 49 33 61 / 60 50 10 10 BRD 49 55 39 61 / 10 30 10 10 HYR 48 59 37 60 / 40 40 10 10 ASX 50 58 40 56 / 50 40 20 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ AVIATION...GSF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1158 AM CDT MON MAY 28 2012 .UPDATE... UPDATED TO INCLUDE 18Z AVIATION DISCUSSION BELOW. && .DISCUSSION... /ISSUED 1002 AM CDT MON MAY 28 2012/ VISIBLE IMAGERY SHOWS MOSTLY SUNNY SKIES ACROSS THE AREA AT THE CURRENT TIME. SOME LINGERING CLOUDS CAN BE FOUND EXTENDING FROM WESTERN LAKE SUPERIOR SOUTH THROUGH THE EASTERN METRO AREA... IN ASSOCIATION WITH A VORTICITY LOBE SEEN IN WATER VAPOR IMAGERY AND THE LATEST RAP ANALYSIS. AN AREA OF CLOUDS AND DYING CONVECTION CAN BE FOUND OVER NORTHWEST MINNESOTA. FORCING HAS RUN OUT AHEAD OF THIS ACTIVITY... SO ALTHOUGH IT MAY FESTER FOR A BIT MOST INDICATIONS ARE THAT IT SHOULD WEAKEN/DIE OVERALL... AT LEAST FOR A LITTLE WHILE. SURFACE ANALYSIS SHOWS AN INITIAL PRE-FRONTAL TROUGH COINCIDENT WITH THE EASTERN CLOUD BAND... AND THE ACTUAL COLD FRONT LIKELY EXTENDING FROM NEAR THE DAKOTA BORDER SOUTH INTO EASTERN NEBRASKA... WHERE A GOOD DEWPOINT GRADIENT CAN BE FOUND. THIS WILL MARCH EAST THROUGH THE DAY TODAY... WITH THE UPPER LOW ALSO SLIDING EAST AND AN LOBE OF UPPER LEVEL PV WORKING INTO WESTERN AND CENTRAL MINNESOTA DURING THE AFTERNOON. THE VARIOUS CONVECTION ALLOWING MODELS... INCLUDING THE HRRR... SPC/EMC WRFNMM... LOCAL WRFARW... AND NSSL WRFARW... ALL SUGGEST A RE- DEVELOPMENT OF CONVECTION NEAR THE SECONDARY FRONTAL BOUNDARY AS IT SWEEPS EAST THROUGH THE FORECAST AREA THIS AFTERNOON INTO EARLY THIS EVENING. AN AXIS OF MLCAPE AOA 1000 J/KG WILL PRECEDE THE BOUNDARY... ALONG WITH DEEP LAYER SHEAR AOA 35 KT. LOW LEVEL SHEAR LOOKS TO BE MEAGER... WHICH SHOULD KEEP A WIDESPREAD DAMAGING WIND THREAT IN CHECK. BUT WILL FREEZING LEVEL HEIGHTS DROPPING AS MID- LEVEL COLD AIR WORKS ACROSS THE REGION... EXPECT SOMEWHAT ORGANIZED STORMS RESULTING FROM THE COMBINATION OF DECENT MLCAPE AND DEEP LAYER SHEAR TO PRODUCE SOME LARGE HAIL ACROSS THE AREA. THE PRIMARY THREAT WILL BE NORTH OF A LINE FROM AROUND LITCHFIELD TO LADYSMITH... MAINLY FROM 2 PM TO 7 PM. ANY DECENT STORM COULD PRODUCE SOME SMALL HAIL GIVEN THE CHILLY TEMPERATURES ALOFT... WHILE ANYTHING THAN MANAGES TO TAKE ADVANTAGE OF THE DEEP LAYER SHEAR AND BETTER ORGANIZE ITSELF COULD PRODUCE HAIL GREATER THAN AN INCH IN DIAMETER. MADE SOME MINOR ADJUSTMENTS TO THE GOING FORECAST WITH RESPECT TO TIMING AND LOCATION OF POPS... WITH SOME ADDITIONAL ADJUSTMENTS LIKELY THROUGH THE DAY AS THINGS START TO TAKE SHAPE. FORECAST HIGHS WILL NEED SOME ADJUSTMENTS GIVEN CURRENT OBS/TRENDS... PARTICULARLY OUT WEST WHERE THE BOUNDARY HASN/T SLIPPED THROUGH YET. && .AVIATION.../18Z TAF ISSUANCE/ OVERALL... VFR CONDITIONS WILL PREDOMINATE THROUGH THE FORECAST PERIOD. THE UPPER LOW TO OUR NORTHWEST WILL MIGRATE EAST INTO THE AREA THROUGH THE PERIOD... WORKING IN CONCERT WITH A SECONDARY FRONTAL BOUNDARY TO KICK OFF SOME SCATTERED SHRA/TSRA THIS AFTERNOON... THEN PERHAPS A FEW ISOLATED SHRA ON TUESDAY AFTERNOON. CEILINGS WITH ANY SHRA/TSRA WILL MAINLY BE VFR WITH JUST SOME BRIEF MVFR POSSIBLE. CONFIDENCE IN TIMING LOCATION OF ACTIVITY IS TOO LOW TO SPECIFICALLY MENTION ANYTHING OTHER THAN VFR VISIBILITIES... AND NO PREVAILING THUNDER AT THIS POINT. BEST CHANCES THIS AFTERNOON WILL BE ACROSS THE NORTHERN SITES... WITH KMSP LIKELY NEAR THE SOUTHERN EDGE OF ANYTHING THAT MANAGES TO GET GOING. WOULD EXPECT SCATTERED CONVECTION TO DEVELOP ACROSS THE WESTERN OR CENTRAL PORTION OF THE AREA AROUND 19Z OR 20Z... THEN MIGRATE EAST THROUGH THE AFTERNOON INTO EARLY EVENING... ONCE AGAIN MAINLY IMPACTING LOCATIONS ACROSS THE NORTH HALF OF THE FORECAST AREA. WINDS WILL SHIFT FROM SOUTHWEST TO WEST-NORTHWEST WITH THE FRONTAL PASSAGE... ALTHOUGH SOME BRIEF NORTH-NORTHWEST WINDS ARE CURRENTLY IMPACTING THE NORTHWEST PART OF THE AREA DUE TO SOME OUTFLOW FROM EARLIER CONVECTION. THAT BRIEF PERIOD OF NORTH-NORTHWEST WINDS MAY IMPACT KSTC AND PERHAPS INTO KRWF... BUT AT THIS POINT AM NOT MENTIONING IT ANY FARTHER SOUTH OR EAST. MORE WIDESPREAD STRATOCU IS EXPECTED TUESDAY AS THE THERMAL TROUGH MOVES INTO THE REGION... WITH SOME INITIAL CEILINGS AOB 3K FT POSSIBLE BEFORE RISING BACK INTO VFR RANGE. KMSP... TAF REFLECTS FORECAST EXPECTATIONS WITH MAIN UNCERTAINTY BEING WITH THE CHANCES FOR SHRA/TSRA THIS AFTERNOON. IF/WHEN ACTIVITY DEVELOPS UPSTREAM WILL AMEND AS NEEDED TO BETTER REFLECT PROBABILITY AND TIMING OF THINGS. SOME UNCERTAINTY IS ALSO ASSOCIATED WITH TIMING AND INITIAL HEIGHT OF CEILINGS MOVING INTO THE AREA ON TUESDAY... WITH +/- 3 HOURS TIMING AND PERHAPS 500FT DIFFERENCES IN CEILING POSSIBLE. //OUTLOOK FOR KMSP FOR TUESDAY NIGHT THROUGH FRIDAY... TUESDAY NIGHT...MVFR CEILINGS POSSIBLE EARLY. WEDNESDAY THROUGH THURSDAY NIGHT...VFR CONDITIONS EXPECTED. FRIDAY...MVFR CEILINGS POSSIBLE. && .PREV DISCUSSION... /ISSUED 413 AM CDT MON MAY 28 2012/ AFTER AN ACTIVE NIGHT WITH SEVERE WEATHER AND FLOODING RAINS...THINGS HAVE QUIETED DOWN ACROSS THE CWA. COULD SEE A FEW SHOWERS AND THUNDERSTORMS TODAY...WITH COOLER WEATHER IN STORE FOR THIS UPCOMING WEEK. TODAY AND TUESDAY...EARLY MORNING WATER VAPOR IMAGERY SHOWED A BEAUTIFUL OCCLUDED UPPER LEVEL LOW OVER THE MT/ND BORDER...WITH RAP H500 MINIMUM TEMP ANALYZED AT -23C. AS THIS UPPER LEVEL LOW MOVES EASTWARD TODAY...COLDER MIDLEVEL TEMPS WILL SPREAD ACROSS THE REGION RESULTING IN DYNAMIC DESTABILIZATION. IN ADDITION TO THE COOLING TEMPS ALOFT...AFTERNOON HEATING SHOULD ELIMINATE ANY CIN...AND SOUNDINGS SHOW THE POTENTIAL FOR A FEW HIGH BASED SHOWERS AND THUNDERSTORMS TODAY. IN FACT...THIS PHENOMENON WAS RESPONSIBLE FOR THE SHOWERS AND THUNDERSTORMS ACROSS SOUTH DAKOTA THIS MORNING. THEREFORE...HAVE INCREASED POPS ACROSS THE NORTHERN AND WESTERN CWA TODAY. THE WELL MIXED BOUNDARY LAYER AS INDICATED BY THE INVERTED-V FORECAST SOUNDINGS WOULD SUPPORT THE POTENTIAL FOR A FEW STRONGER WIND GUSTS WITH THESE SHOWERS AND THUNDERSTORMS. USED 3HR GRIDS TO SHOWS THE POPS DECREASING AFTER SUNSET...ONLY TO RETURN TOMORROW AFTERNOON. ALSO...WEST NORTHWEST WIND WILL BE BREEZY DURING THE AFTERNOON...BUT SHOULD REMAIN BELOW ADVISORY CRITERIA. WEDNESDAY THROUGH THE WEEKEND...AN UPPER LEVEL WAVE CURRENTLY OF THE BRITISH COLUMBIA COAST WILL CROSS THE NORTHERN ROCKIES TOMORROW AND SLIDE SOUTHEAST DOWN THE MISSOURI RIVER VALLEY. THIS CLIPPER-LIKE SYSTEM WILL ALLOW CANADIAN HIGH PRESSURE TO BUILD ACROSS THE REGION...WITH TEMPERATURES WELL BELOW NORMAL FOR THE MIDDLE OF THE WEEK. AS THE UPPER LEVEL WAVE CONTINUES ON ITS SOUTHEASTWARD MARCH TOWARD THE SOUTHERN PLAINS...THE FORCING ASSOCIATED WITH IT WILL CAUSE A SURFACE LOW PRESSURE SYSTEM TO DEVELOP. THIS WILL LIKELY RESULT IN SEVERE WEATHER ACROSS THE SOUTHCENTRAL US...AND CLOUDY SKIES WITH COOLER TEMPS AND A FEW SCATTERED SHOWERS OVER THE UPPER MIDWEST...ESPECIALLY NEAR THE IA/MN/WI BORDER. THE ECMWF 28.00 IS SLIGHTLY MORE PROGRESSIVE THAN THE GEM OR GFS...BUT EITHER WAY IT LOOKS LIKE THURSDAY AND FRIDAY WILL FEEL MORE LIKE MID APRIL THAN LATE MAY. ONCE THIS LOW MOVES EASTWARD FOR THE WEEKEND...NORTHWEST FLOW WILL SET UP ACROSS THE REGION RESULTING IN WARMER TEMPERATURES CLOSER TO THE SEASON AVERAGE FOR EARLY JUNE. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ ///JRB
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1219 PM CDT MON MAY 28 2012 .SHORT TERM... ISSUED AT 319 AM CDT MON MAY 28 2012 (TODAY AND TONIGHT) MAIN CONCERN TODAY WILL BE THE POTENTIAL FOR A FEW SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT. AREA OF SHOWERS AND SCATTERED THUNDERSTORMS OVER WESTERN IOWA SHOULD PROGRESS EASTWARD THIS MORNING. VORT MAX SEEN ON WATER VAPOR IMAGERY OVER CENTRAL NEBRASKA EARLY THIS MORNING SHOULD MOVE NORTHEASTWARD AND WILL SUPPLY LIFT FOR THESE STORMS. ADDITIONAL STORMS MAY DEVELOP AS FAR SOUTH AS NORTHERN MISSOURI AND MOVE INTO NORTHEAST MISSOURI BETWEEN 12-15Z BASED ON LATEST RAP RUN DEPICTING DECENT 925-850MB MOISTURE CONVERGENCE OVER THESE AREAS. CHANCES WILL INCREASE THROUGH THE DAY AS COLD FRONT CURRENTLY OVER THE CENTRAL PLAINS MOVES EASTWARD AND REACHES KUIN-KCOU LINE BY 00Z. MLCAPES BY MID AFTERNOON WILL BE IN THE 1500-2500 J/KG RANGE WITH LIMITED CINH. STILL DOES NOT LOOK LIKE THERE WILL BE MUCH LOW LEVEL CONVERGENCE OR LARGE SCALE ASCENT CAUSE BY A SHORTWAVE TO FORCE WIDESPREAD DEVELOPMENT. SO AREA EXTENT OF STORMS STILL LOOKS TO BE SCATTERED UNLESS COLD POOLS CAN ORGANIZE AND FORCE MORE WIDESPREAD COVERAGE. DEEP LAYER SHEAR STILL ONLY LOOKS TO BE IN THE 25-35 KT RANGE WHICH FAVORS MULTICELLS...THOUGH AMOUNT OF CAPE STILL SUGGEST THE POTENTIAL FOR DAMAGING WIND GUSTS AND SOME LARGE HAIL INTO THE EVENING. COLD FRONT WILL CLEAR THE CWA LATE TONIGHT...SO SHOWERS AND THUNDERSTORMS WILL END FROM NORTHWEST TO SOUTHEAST AFTER MIDNIGHT. TEMPERATURES HAVE MOSTLY BEEN AT OR BELOW FORECAST MOS GUIDANCE THE PAST TWO DAYS...AND DO NOT EXPECT THEM TO EXCEED THESE VALUES TODAY GIVEN MORE CLOUDS. BRITT && .LONG TERM... ISSUED AT 412 AM CDT MON MAY 28 2012 (TUESDAY THROUGH SUNDAY) LOOKS LIKE THE PRECIPITATION SHOULD PUSH SE OF OUR FORECAST AREA BY TUE AS THE COLD FRONT MOVES SE OF THE AREA WITH A SFC RIDGE BUILDING SEWD INTO MO. TEMPERATURES WILL BE COOLER TUE THROUGH WED WITH LOW LEVEL CAA...ALTHOUGH STILL ABOVE NORMAL ON TUE. ELEVATED CONVECTION SHOULD MOVE INTO THE AREA WED NGT AS THE NAM MODEL DEPICTS STRONG 850 MB WAA...THETA E ADVECTION AND MOISTURE CONVERGENCE OVER CNTRL MO ON NOSE OF S-SWLY LOW LEVEL JET. MODELS SHOWING A GOOD CHANCE OF WIDESPREAD SHOWERS AND STORMS ON THU AS AN UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE EWD THROUGH THE REGION. THE GFS MODEL IS FURTHER S WITH THE MAIN UPPER LEVEL LOW VERSUS THE ECMWF SOLUTION AND IS ALSO LESS PROGRESSIVE WITH THE UPPER LEVEL LOW AND ASSOCIATED PRECIPITATION. FOR NOW WILL GO WITH THE MORE PROGRESSIVE ECMWF SOLUTION WHICH APPEARS MORE REALISTIC FOR THIS TIME OF YEAR AND MORE LIKELY TOO VERIFY THAN THE GFS. WILL END THE POPS OR LOWER THEM DRAMATICALLY BY FRI AS THE UPPER LEVEL TROUGH AND ASSOCIATED SFC LOW MOVE E OF OUR AREA. TEMPERATURES WILL BE COLDER AND BELOW NORMAL ON THU MAINLY DUE TO CLOUDS AND PRECIPITATION AND CONTINUED RELATIVELY COLD THU NGT AND FRI WITH NLY WINDS BRINGING COLDER AIR INTO THE REGION BEHIND THE 850MB/SFC LOW. THE ECMWF MODEL DROPS THE 4 DEGREE C 850 MB ISOTHERM SWD TO STL BY 12Z FRI. TEMPERATURES WILL BEGIN TO MODERATE THIS WEEKEND AS UPPER LEVEL HEIGHTS RISE BEHIND THE UPPER LEVEL TROUGH AND THE LOW LEVEL WINDS BECOME MORE S-SWLY BEHIND THE SFC RIDGE. GK`S && .AVIATION... ISSUED AT 1202 PM CDT MON MAY 28 2012 A CDFNT WILL PUSH THRU THE REGION THIS EVENING AND OVERNIGHT. SCT TSRA ARE EXPECTED TO DEVELOP ALONG THIS FNT LATE THIS AFTERNOON AND THROUGH THE OVERNIGHT HOURS. DUE TO LOW PROBABILITY OF IMPACTING TERMINAL...HAVE KEPT MENTION AS VCTS FOR NOW. CHANCES INCREASE THIS EVENING...BUT AREA SHUD BE S OF SUS/CPS TERMINALS. BEHIND THE FNT...COOLER AND DRIER AIR WILL MOVE IN WITH NLY WINDS GRADUALLY VEERING TO BECOME SELY TO SLY BY TUES MORNING. VFR CONDITIONS ARE EXPECTED THRU THE TAF PERIOD OUTSIDE OF ANY CONVECTION. SPECIFICS FOR KSTL...GUSTY WINDS ARE EXPECTED TO DIMINISH THIS EVE BEHIND A CDFNT. TSRA WILL BE POSSIBLE ALONG THIS FNT...BUT BETTER CHANCES WILL BE S OF THE TERMINAL TONIGHT. HAVE THEREFORE KEPT VCTS FOR NOW. NWLY WINDS BEHIND THE FNT WILL GRADUALLY VEER TO SELY...THEN SLY ON TUES. WITH WINDS UNDER 5 KTS EXPECTED...HAVE KEPT AS VRB FOR NOW. TILLY && .CLIMATE... ISSUED AT 653 PM CDT MON MAY 21 2012 HERE IS A LIST OF RECORD HIGH TEMPERATURES FOR MONDAY... ...MONDAY... (5/28) ST. LOUIS 93 2006 COLUMBIA 91 2006 QUINCY 94 1914 && .LSX WATCHES/WARNINGS/ADVISORIES... MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS TULSA OK
1215 PM CDT MON MAY 28 2012 .DISCUSSION... THE 18Z TAF DISCUSSION CAN BE FOUND BELOW. && .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. VFR WILL PREVAIL...OUTSIDE OF SCT TS ACTIVITY...THIS FORECAST PERIOD. COLD FRONT WILL PUSH INTO NE OK AND NW AR TONIGHT. THE LATEST MODEL GUIDANCE SUGGEST STORMS WILL DEVELOP IN THE VCNTY OF THE FRONT BTWN 00Z AND 03Z THIS EVENING. OTHER STORMS WHICH ARE EXPTD TO DVLP THIS AFTERNOON OVER SW OK COULD AFFECT THE KMLC TAF SITE THIS EVENING AS WELL. COVERAGE OF STORMS IS NOT YIELDING ENUF CONFIDENCE TO INCLUDE TEMPOS IN ANY TAF AT THIS POINT...AND WILL INSTEAD STAY WITH CONSERVATIVE VCTS MENTION. STORMS SHOULD WEAKEN AFTER 06Z WITH NO MENTION IN THE FORECAST FOR THE 12-18Z TUESDAY MORNING TIME FRAME. LACY && .PREV DISCUSSION... /ISSUED 945 AM CDT MON MAY 28 2012/ DISCUSSION... MORNING SURFACE MAP SHOWS COLD FRONT FROM CENTRAL KS DOWN INTO WESTERN OK. THE FRONT WILL BE SLOW TO MAKE PROGRESS EAST TODAY...WITH LITTLE IN THE WAY OF UPPER SUPPORT AND NEARLY PARALLEL FLOW ALOFT TO THE BOUNDARY. BAND OF MID CLOUD STRETCHES FROM EASTERN OK UP INTO MO...WHERE SOME ELEVATED SHOWERS AND A FEW LIGHTNING STRIKES HAVE BEEN OBSERVED. THE LATEST SHORT-TERM MODEL GUIDANCE...INCLUDING THE LATEST RUNS OF THE HRRR AND THE 12Z NAM...SUGGEST THAT A FEW ELEVATED SHOWERS AND POSSIBLY A FEW RUMBLES OF THUNDER ARE POSSIBLE THIS AFTERNOON ALONG THIS MOISTURE AXIS ALOFT. OTHERWISE...SURFACE BASED CONVECTION WILL BE INITIATING OVER NW TX OR FAR SW OK BY LATE THIS AFTERNOON NEAR A SURFACE LOW AND AT THE TAIL END OF THE FRONT. THIS CONVECTION WILL PROBABLY CONGEAL INTO AN MCS AND MOVE EAST OR SOUTHEAST ACROSS SOUTHERN OK AND NORTHERN TX TONIGHT. FARTHER NORTH...THE NAM SUGGESTS THAT SCATTERED CONVECTION WILL GET GOING THIS EVENING /AROUND 03Z OR SO/ ROUGHLY ALONG THE I-44 CORRIDOR WHERE THE LOW LVL FRONTAL ZONE WILL BE CO-LOCATED. THE CONVECTION SHOULD GRADUALLY WEAKEN AFTER MIDNIGHT. I HAVE MADE SOME ADJUSTMENTS TO THE TEMPS AND CLOUD COVER...OTHERWISE THE GOING FORECAST APPEARS TO BE ON TRACK. I LEFT THE SLIGHT CHANCE POPS FOR THIS AFTERNOON OVER NORTHEAST OK ALONE FOR REASONS STATED ABOVE. UPDATED PRODUCTS HAVE BEEN SENT. LACY PREV DISCUSSION... /ISSUED 617 AM CDT MON MAY 28 2012/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. FOR THE 12 Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGHOUT THE DAY TODAY. MID CLOUDS SHOULD THICKEN UP AS A COLD FRONT APPROACHES NORTHEAST OKLAHOMA LATE AFTERNOON INTO EARLY EVENING. THUNDERSTORM CHANCES WILL INCREASE FROM EARLY EVENING ON AT ALL SITES. PREV DISCUSSION... /ISSUED 323 AM CDT MON MAY 28 2012/ DISCUSSION... SURFACE LOW CURRENTLY MOVING INTO CENTRAL KANSAS EARLY THIS MORNING WITH FRONTAL BOUNDARY EXTENDING SOUTHWEST INTO THE OK/TX PANHANDLES. FRONT WILL PUSH INTO CENTRAL/NORTHEAST OKLAHOMA BY LATE AFTERNOON...MOVING TO NEAR A OKLAHOMA CITY/PONCA CITY LINE BY 00Z. HIGH TEMPERATURES WILL BE DEPENDENT ON AFTERNOON CLOUD COVER AND HOW QUICKLY STORMS FIRE ALONG THE FRONT. FOLLOWED THE WARMER MET GUIDANCE BUT THIS COULD STILL BE TOO COOL GIVEN THE WARM 850 MB TEMPS/LIGHT SOUTHWEST WINDS AHEAD OF BOUNDARY...ESPECIALLY IF THE CLOUD COVER REMAINS LIMITED. SCATTERED SHOWERS/THUNDERSTORMS SHOULD DEVELOP BY EARLY EVENING ALONG STALLED FRONT BEFORE DECREASING IN COVERAGE BY LATE EVENING. A FEW STORMS COULD BRIEFLY REACH SEVERE LIMITS GIVEN THE HIGH SURFACE BASED INSTABILITY EXPECTED...HOWEVER WEAK DEEP LAYER SHEAR SHOULD LIMIT OVERALL SEVERE THREAT. SEVERAL ROUNDS OF PRECIPITATION POSSIBLE TUESDAY THROUGH THURSDAY WITH THE POTENTIAL FOR MULTIPLE THUNDERSTORM COMPLEXES TO TRAVERSE THE REGION. TIMING WILL REMAIN CHALLENGING AND WILL LIKELY PLAY HAVOC ON TEMPERATURE FORECAST DEPENDING ON EXACT MCS EVOLUTION. MODELS IN GENERAL AGREEMENT WITH THE BEST THUNDERSTORM CHANCES WEDNESDAY NIGHT INTO THURSDAY AS UPPER JET STREAK DIVES SSE ALONG THE LEE OF THE ROCKIES. GREATEST SEVERE/HEAVY RAINFALL THREAT WILL LIKELY OCCUR DURING THIS TIME...ALTHOUGH TUESDAY WILL ALSO HAVE AT LEAST A LIMITED SEVERE THREAT WITH ANY MCS ACTIVITY. MAIN UPPER TROUGH WILL BEGIN TO SHIFT EAST OF THE AREA THURSDAY NIGHT INTO FRIDAY WITH PRECIPITATION CHANCES ENDING. GENERALLY WENT WITH A BLEND OF THE WARMER ECMWF/COOLER MEX GUIDANCE THROUGH THE REMAINDER OF THE EXTENDED PERIODS AS SURFACE HIGH SHIFTS EAST BY SUNDAY WITH RETURN FLOW DEVELOPING. && .PRELIMINARY POINT TEMPS/POPS... TUL 71 90 70 87 / 40 40 50 30 FSM 70 91 69 89 / 50 40 40 30 MLC 70 89 69 88 / 50 30 50 30 BVO 64 89 64 85 / 20 40 50 20 FYV 65 87 62 83 / 50 40 40 30 BYV 68 87 63 82 / 50 40 40 30 MKO 67 89 67 86 / 50 40 50 30 MIO 66 89 65 84 / 30 40 50 30 F10 70 89 67 86 / 50 40 50 30 HHW 69 91 70 90 / 40 20 50 20 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...30
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1255 PM CDT MON MAY 28 2012 .AVIATION... CONCERNS INCLUDE TIMING OF CONVECTION INTO DFW AIRPORTS TONIGHT AND LOW MVFR/HIGH IFR POTENTIAL ACROSS WACO BEFORE DAYBREAK TUESDAY. VFR CONDITIONS WILL CONTINUE THROUGH THE MAJORITY OF FORECAST WITH A SLIGHT RISK FOR SEVERE STORMS ACROSS NORTHWEST PARTS OF NORTH TEXAS. SOUTH FLOW 7-12 KTS WILL BE THE RULE...THOUGH WINDS COULD BRIEFLY BECOME SOUTHEAST FOR A FEW HOURS THIS EVENING. TWO BOUNDARIES OF CONCERN ARE IN QUESTION. A SURFACE TROUGH STRETCHED FROM NEAR ABILENE...TO BOWIE...TO SOUTH OF NORMAN OKLAHOMA BACK TO A WEAK SURFACE LOW NORTH OF MIDLAND TEXAS. FURTHER NORTHWEST...A STALLED FRONT WAS FROM NEAR LUBBOCK...TO SNYDER...TO NORTH OF ALTUS OKLAHOMA. WE THINK BETTER CONVERGENCE FOR STORM INITIATION TO OCCUR WITH THE FRONT VERSUS THE SURFACE TROUGH BASED ON WIND DIRECTION AND BEST CONVERGENCE POTENTIAL EXPECTED TO BE ALONG THE ACTUAL COLD FRONT. A ROGUE ISOLATED THUNDERSTORM MAY FORM OFF THE SURFACE TROUGH BY 00Z NORTHWEST OF DFW AIRPORT AND WE WILL MONITOR TRENDS CLOSELY. WRF AND SREF MODELS SHOW INITIATION JUST NORTHWEST OF DFW BY 02Z... WITH NAM12 AND HRRR MODELS INDICATING A LATER TRENDS MORE IN THE 04Z-6Z TIME FRAME FOR THE METRO AIRPORTS. HAVE DECIDED TO TAKE A MEAN AND INTRODUCE VCTS/CB FOR DFW METRO AIRPORTS IN THE 02Z-05Z TIME FRAME WITH CONFIDENCE NOT VERY HIGH AT THE MOMENT DUE TO MESOSCALE NATURE OF DEVELOPMENT. TIMES AND POSSIBLY BRIEF TEMPO GROUPS CAN BE INSERTED BY THE 00Z TAF ISSUANCE ONCE CONVECTION DEVELOPS AND TIMING IS MORE CERTAIN. STRONG TO SEVERE WEATHER IS POSSIBLE...DESPITE SOME MARGINAL CINH DEVELOPING BY MID EVENING WITH LAPSE RATES ALOFT FAIRLY STEEP. WACO COULD SEE SOME LIGHT SHOWERS WELL AFTER 06Z...BUT WITH ACTIVITY EXPECTED TO RAPIDLY DIMINISH IN MORE STABLE ENVIRONMENT...HAVE ELECTED TO LEAVE OUT. WILL INTRODUCE A BRIEF WINDOW FOR LOW MVFR CIGS AROUND DAYBREAK TUESDAY. 05/ && .UPDATE... LATE THIS MORNING...A SUBTLE COLD FRONT EXTENDED FROM NORTHERN OKLAHOMA...TO JUST EAST OF CHILDRESS TX...SOUTHWESTWARD THROUGH LUBBOCK TX. THE BOUNDARY CONNECTS UP WITH A DRYLINE OVER THE WESTERN PART OF THE STATE. GOOD INSTABILITY AND PLENTY OF MOISTURE WILL BE PRESENT AS THE FRONT SLIDES SLOWLY SOUTHEAST TOWARDS THE NORTHWESTERN COUNTIES OF NORTH TEXAS AND STALLS LATE THIS AFTERNOON. THUNDERSTORMS ARE EXPECTED TO DEVELOP JUST WEST AND NORTHWEST OF THE AREA DURING PEAK HEATING...LIKELY SOMETIME IN THE 4 TO 6 PM TIME FRAME. PROJECTED STORM MOTION BRINGS ACTIVITY EASTWARD INTO THE NORTHWESTERN COUNTIES BEFORE SUNSET THIS EVENING. THE FORECAST WILL REMAIN UNCHANGED FOR NOW...WITH HIGHEST POPS OVER THE NORTHWEST COUNTIES...TAPERING OFF TO SLIGHT CHANCE LATER TONIGHT AS FAR EAST AS A PARIS TO DALLAS TO COMANCHE LINE. POPS MAY BE ADJUSTED LATER IN THE DAY DEPENDING ON HOW FAR SOUTHEAST THE FRONT PROGRESSES BEFORE STALLING...AND HOW MUCH COVERAGE OCCURS AS STORMS MOVE IN FROM THE WEST. A FEW STORMS COULD BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS THIS EVENING AND SPC SLIGHT RISK REMAINS IN PLACE FOR ABOUT THE NORTHWESTERN QUARTER OF THE CWA. 30 && .PREV DISCUSSION... /ISSUED 300 AM CDT MON MAY 28 2012/ A FEW CHANGES WILL TAKE PLACE IN THE WEATHER PATTERN THROUGH THE WEEK THAT SHOULD BRING SOME RAIN/THUNDERSTORM CHANCES AS WELL AS COOLER TEMPERATURES TO NORTH TEXAS. A COLD FRONT WILL MOVE ACROSS THE HIGH PLAINS TODAY AS AN UPPER LOW MOVES EAST ACROSS THE UPPER MID WEST. THE COLD FRONT SHOULD STALL NORTHWEST OF NORTH TEXAS LATE THIS AFTERNOON. SCATTERED STORMS ARE EXPECTED TO DEVELOP ALONG THE FRONT AS A SHORT WAVE MOVES THROUGH WESTERLY FLOW ALOFT. INSTABILITY AND VERTICAL WIND SHEAR WILL SUPPORT SOME SEVERE STORMS ACROSS THE NORTHWEST ZONES. LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY HAZARDS...MAINLY THIS EVENING. SCATTERED THUNDERSTORMS WILL BE POSSIBLE ACROSS THE NORTHERN HALF OF NORTH TEXAS TONIGHT/TUESDAY AS THE SHORT WAVE MOVES EAST ACROSS THE REGION. HOWEVER...AS STORMS APPROACH THE INTERSTATE 35 CORRIDOR THEY WILL ENCOUNTER LESS INSTABILITY AND SHOULD WEAKEN. ANOTHER SHORT WAVE WILL MOVE ACROSS OKLAHOMA TUESDAY NIGHT AND THUNDERSTORMS SHOULD DEVELOP ALONG THE STALLED FRONT NORTH OF THE RED RIVER. SCATTERED STORMS WILL BE POSSIBLE ACROSS THE NORTHERN HALF OF THE REGION ON ANY SOUTHWARD MOVING OUTFLOW BOUNDARY AND THERE WILL EVEN BE A POTENTIAL FOR MCS DEVELOPMENT. THEREFORE... WILL KEEP SOME CHANCE POPS ALONG THE RED RIVER AND DECREASE POPS FROM NORTH TO SOUTH. A FEW STORMS MAY LINGER IN THE NORTH WEDNESDAY...BUT THE BETTER STORM CHANCES WILL ARRIVE WEDNESDAY NIGHT THROUGH THURSDAY AS THE COLD FRONT FINALLY MOVES ACROSS THE REGION. THE BEST MOISTURE AND INSTABILITY WILL BE ACROSS THE EASTERN ZONES. THUNDERSTORM CHANCES WILL END THURSDAY EVENING AS MUCH DRIER AND COOLER AIR FILTERS INTO THE REGION BEHIND THE COLD FRONT. FRIDAY AND SATURDAY WILL BE COOLER AND DRIER WITH MOSTLY CLEAR SKIES. SOUTHERLY WINDS AND LOW LEVEL MOISTURE WILL RETURN ON SUNDAY AS A SURFACE TROUGH DEVELOPS ACROSS THE NORTHERN AND CENTRAL HIGH PLAINS. TEMPERATURES FOR THE FIRST HALF OF THE WORK WEEK WILL BE WARM WITH AFTERNOON HIGHS GENERALLY IN THE LOWER AND MIDDLE 90S AND LOWS IN THE 70S. THURSDAY THROUGH SATURDAY WILL SEE AFTERNOON HIGHS GENERALLY IN THE 80S WITH LOWS MAINLY IN THE 60S. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 74 93 74 92 / 10 20 10 30 10 WACO, TX 93 71 92 72 92 / 5 10 5 10 10 PARIS, TX 90 70 89 70 90 / 10 10 20 40 20 DENTON, TX 92 72 91 71 91 / 10 30 20 30 20 MCKINNEY, TX 91 71 91 71 91 / 10 20 20 30 20 DALLAS, TX 93 75 93 74 92 / 5 20 10 30 10 TERRELL, TX 92 72 91 71 91 / 5 10 10 30 10 CORSICANA, TX 92 72 91 72 91 / 5 10 5 20 10 TEMPLE, TX 91 69 91 71 91 / 5 5 5 10 10 MINERAL WELLS, TX 95 69 94 70 91 / 10 20 20 30 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/30
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1236 PM CDT MON MAY 28 2012 .AVIATION... CONVECTIVE CHANCES WILL BE LIMITED THIS AFTERNOON AT BOTH TAF SITES ESPECIALLY KLBB. HAVE MAINTAINED A VCTS AT KCDS GIVEN MODEL TRENDS OF SUPERCELL SPLITS AND POTENTIAL FOR LEFT MOVERS ACROSS THE ROLLING PLAINS. OTHERWISE VFR CONDITIONS EXPECTED WITH RELATIVELY LIGHT SOUTHEASTERLY WINDS BELOW 15 KT. STRATUS EAST OF THE DRYLINE MAY ATTEMPT TO DEVELOP AROUND DAYBREAK TUE BUT CONFIDENCE TOO LOW ATTM TO MENTION FOR KCDS. && .PREV DISCUSSION... /ISSUED 1039 AM CDT MON MAY 28 2012/ UPDATE... INCREASED POPS SOUTHEAST OF A PADUCAH TO POST LINE THIS AFTERNOON BASED ON 12Z MODEL RUNS AND LATEST HI-RES CONVECTION ALLOWING MODELS. ALL PRETTY MUCH IN AGREEMENT ON ISOLD-SCT CONVECTION DEVELOPING ALONG AND SOUTH OF RETREATING WARM FNT THIS AFTER 21Z. FORECAST SOUNDINGS SHOWING SBCAPE IN WARM SECTOR AROUND 1700 J/KG WITH DEEP LAYER SHEAR ON ORDER OF 35KT. UPPER AIR ANALYSIS SHOWS A JET STREAK NEAR TWC @ 12Z WHICH LENGHTENS THE HODOGRAPH SOME THIS EVENING AND SHOULD HELP TO ORGANIZE CONVECTION THAN CAN GET GOING. STRONG CAP THAT HAS BEEN IN PLACE LAST FEW DAYS MAY STILL BE A LIMITING FACTOR TO MORE WIDESPREAD CONVECTION AND EXTENT OF PRECIP ESPECIALLY FURTHER WEST AND NORTH ACROSS THE AREA BUT ENOUGH CONFIDENCE EXISTS IN STORMS TO INCREASE MENTION SOUTHEAST OF LUBBOCK ALONG EDGE OF EML. PREV DISCUSSION... /ISSUED 234 AM CDT MON MAY 28 2012/ SHORT TERM... THE BROAD UA LOW CONTINUED TO SLOWLY TRANSLATE ENE TOWARDS THE HIGH PLAINS/SOUTHERN SASKATCHEWAN PER 07Z WATER VAPOR IMAGERY. ITS SOUTHERN PERIPHERY SKIRTED ACROSS THE PANHANDLES WHICH HAS RESULTED IN A BRIEFLY STRONG ISOLATED THUNDERSTORM ACROSS THE EASTERN TEXAS PANHANDLE...THAT HAS SINCE SHIFTED EAST ACROSS WESTERN OKLAHOMA. WHAT IS OF CONCERN IS ADDITIONAL CONVECTION DEVELOPING SOUTH AND EAST OF THE SAID STORM IN THE NEXT COUPLE OF HOURS...COINCIDING WITH A NEARBY PACIFIC FRONT THAT HAS INTERSECTED THE CENTRAL PANHANDLES AND THE FAR NORTHWESTERN SOUTH PLAINS EARLY THIS MORNING. THE FRONT IS EXPECTED TO MOVE SOUTH AND EAST ACROSS THE EASTERN PANHANDLES /AOA 08Z/ AND THEN THE NORTHEASTERN SOUTH PLAINS /AOA 10Z/. A LINGERING RETREATING DRYLINE ACROSS THE SOUTHERN PLAINS WILL BE OVERCOME BY THE FRONT AS IS LIKELY WHY THE HRRR AND GFS SOLUTIONS ARE EAGER TO DISPLAY PRECIP ALONG THIS FRONTAL BOUNDARY.... MORESO BETWEEN 06Z AND 12Z. THE FRONTAL PUSH IS NOT IMPRESSIVELY STRONG BUT IS QUITE DRY WITH 07Z METARS DISPLAYING 15 KT WIND SPEEDS AND SINGLE DIGITS DEWPOINTS ACROSS THE WESTERN PANHANDLES. CURRENT THINKING IS THE BEST SYNOPTIC LIFT IS JUST TOO FAR NORTH AND THE GFS AND HRRR SOLUTIONS DISPLAYING PRECIP NEAR THE SOUTHEASTERN TEXAS PANHANDLE AT 06Z AND 07Z RESPECTIVELY WAS OBVIOUSLY OVER DONE. THUS THE DRY NAM AND ECMWF SOLUTIONS MAY HAVE A BETTER HANDLE ON THE SITUATION AND THUS WILL MAINTAIN SILENT POPS THIS MORNING. THIS AFTERNOON HOWEVER IS A DIFFERENT STORY AS THE UA LOW MARCHES EAST ACROSS NORTHERN MINNESOTA/SOUTHERN ONTARIO...AND THE FRONT PUSHES FARTHER SOUTHEAST TO NEAR THE SERN ZONES WHERE IT IS THERE THAT IT STALLS /FROM NEAR PADUCAH SW TO DENVER CITY/. SOUTHERLY FLOW SOUTH OF THE FRONT WILL CONTINUE TO DRAW IN MID LEVEL MOISTURE AS INDICATED BY PROGGED PWATS OF 1.65 INCHES AND PERSISTING DEWPOINTS IN THE 60S THIS EVENING. AS TEMPS WARM INTO THE UPPER 80S TO LOWER TO MID 90S...THE CAPPING INVERSION WILL WEAKEN AND IS EXPECTED TO BREAK AOA 29/00Z. AS FLOW ALOFT EVOLVES TO NEAR ZONAL FLOW...A SUBTLE EMBEDDED DISTURBANCE IS EXPECTED TO MOVE ACROSS THE SOUTHERN PLAINS THIS EVENING...THUS SERVING AS THE SYNOPTIC SPARK POSSIBLY NEEDED TO INITIATE STORMS...ESPECIALLY WITH AN UNIMPRESSIVE FRONTAL BOUNDARY IN PLACE. SFC-BASED CAPE OF 1.5-2.5 KG/KG...INVERTED-V SOUNDING PROFILES...VEERING WIND PROFILES...A LINGERING FRONTAL BOUNDARY AND SUBTLE LARGE SCALE ASCENT SUGGEST THE PROSPECT FOR STORMS TO APPROACH STRONG LEVELS...AND PERHAPS BE CAPABLE OF ORGANIZATION WITH LARGE HAIL AND DAMAGING WINDS THE MAIN THREATS. WILL THEREFORE MAINTAIN MENTIONABLE POPS OFF THE CAPROCK WITH EMPHASIS ACROSS THE SERN ZONES...COMMENCING LATE THIS AFTERNOON AND SHIFT BEST PRECIP EASTWARD BY THE END OF THE SHORT TERM PERIOD. LONG TERM... ZONAL UPPER LEVEL FLOW TUESDAY WILL AID MIXING OF THE DRYLINE EWD TO NEAR THE ERN BORDER OF THE FCST AREA WITH POTENTIAL FOR ISOLATED TSRA DEVELOPING NEAR IT LATE AFTN AND EARLY EVENING WITH PREVIOUS FCST SLIGHT CHC POPS LOOKING FINE. WILL THEN SEE UPPER LEVEL VEER TO THE NW AS A RIDGE BUILDS OVER THE WRN CONUS. MODELS CONTINUE TO PROG A SHORT WAVE TROUGH MOVING THROUGH THE NWLY FLOW FROM THE CTNL HIGH PLAINS WEDNESDAY TOWARD ARKANSAS BY THURSDAY MORNING. IT STILL APPEARS THAT THIS TROUGH COULD BRING SOME PRECIP INTO THE NERN ZONES WEDNESDAY NIGHT...WITH SOME LOW LEVEL LIFT FROM A COLD FRONT MOVING THROUGH THE FCST AREA IN THE WAKE OF THE UPPER LOW. MODELS CONTINUE TO STRUGGLE WITH THE STRENGTH OF THE COLD FRONT... THE ONSET OF RETURN FLOW...AND THE AMOUNT OF LOW LEVEL MOISTURE AVAILABLE TO ANY STORMS THAT DEVELOP ON THE HIGH TERRAIN TO THE NW OF THE FCST AREA. 00Z RUN HAVE TRENDED TOWARD A COOLER AND DRIER SOLUTION WITH NW FLOW PRECIP NOT IN THE MODELS UNTIL FRIDAY OR SATURDAY NIGHT. WILL RUN NEAR MOS POPS AND TEMPS IN THE THURSDAY THROUGH SUNDAY PERIOD. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 55 93 57 89 57 / 10 10 10 10 10 TULIA 59 92 61 89 59 / 10 10 10 10 10 PLAINVIEW 62 95 63 92 61 / 20 10 10 10 10 LEVELLAND 59 97 64 95 60 / 10 10 10 10 10 LUBBOCK 63 98 64 96 63 / 20 10 10 10 10 DENVER CITY 61 96 64 95 60 / 10 10 10 10 10 BROWNFIELD 61 98 64 96 61 / 20 10 10 10 10 CHILDRESS 67 97 68 94 65 / 20 20 20 10 20 SPUR 66 97 67 96 65 / 30 10 10 10 10 ASPERMONT 69 99 70 98 67 / 30 20 20 10 20 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24