Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/17/15
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
838 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 837 PM MDT SUN AUG 16 2015
POTENTIAL FOR HEAVY RAIN OVER THE FAR ERN PLAINS HAS DIMINISHED SO
WILL BE DROPPING THE FLASH FLOOD WATCH. OTHERWISE WILL SEE LINGERING
SHOWERS/TSTMS ALONG THE WY-NE BORDER AREA THRU THE REST OF THIS
EVENING AND OVER LINCOLN COUNTY. ELSEWHERE ACTIVITY WILL BE MORE
ISOLD.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 250 PM MDT SUN AUG 16 2015
LOW-LEVEL MOISTURE WILL CONTINUE TO INCREASE ACRS NERN/E-CNTRL CO
DURING THE NEXT 6-12 HOURS AS UPSLOPE FLOW BECOMES BETTER
ESTABLISHED IN THE WAKE OF THE COLD FRONT MOVING SLOWLY SOUTHWARD
ACROSS CENTRAL CO. STG INSOLATION PAST FEW HOURS ALONG THE FRONT
RANGE HAS STEADILY INCREASED BNDRY LAYER CAPES AND STEEPENED LAPSE
RATES. ONLY A MATTER OF TIME WITH ENHANCED OROGRAPHIC CIRCULATION
FOR STORM INITIATION OVER AND ALONG THE FRONT RANGE. MESOSCALE
MODELS INDICATE RAPID STORM FORMATION OVER THE FRONT RANGE MTNS
AND FTHLS WITH WEAK STORM MOTIONS AT THE ONSET. PAST 3 HRS
INTEGRATED PRECIPITABLE WATER AMOUNTS ALONG THE BASE OF THE FTHLS
HAVE INCREASED AROUND A TENTH OF AN INCH. AT 20Z...IPW AT DEN WAS
1.09 INCH. THIS MODEST UPWARD TREAD WILL LIKELY CONTINUE THROUGH
THE AFTERNOON. MEANWHILE MODELS SHOW A BROKEN LINE OF STORMS
SLOWLY MOVING OFF THE FRONT RANGE AND OVER THE NEARBY PLAINS
WITHIN THE NEXT FEW HOURS. A FEW OF THESE STORMS MAY PRODUCE HAIL
UP TO ONE INCH IN DIAMETER...WIND GUSTS TO 45 MPH AND SEVERAL MINS
OF INTENSE RAINFALL POSSIBLY CAUSING MINOR URBAN AND LOWLAND
FLOODING. IT APPEARS THAT THIS STORM FRONT WILL BECOME MORE
ORGANIZED EAST OF THE I-25 CORRIDOR WHERE THE RISK OF SEVERE
WEATHER AND VERY HEAVY RAINFALL WILL BE GREATER. HOURLY RAINFALL
RATES OF 1.5-2.5 INCHES PER HOUR MAY LEAD TO SERIOUS FLASH
FLOODING ON THE FAR PLAINS. LATEST FLASH FLOOD GUIDANCE INDICATES
THAT HOURLY RAINFALL AMOUNTS OF JUST SLIGHTLY OVER 1.5 INCHES
WOULD BE SUFFICIENT TO PRODUCE FLASH FLOODING IN MANY NORTHEAST
CO COUNTIES...AND JUST 1.2 INCHES PER HOUR IN LINCOLN COUNTY. A
FLASH FLOOD WATCH HAS BEEN ISSUED AND WILL GO INTO EFFECT AT 3 PM
MDT TODAY FOR LOGAN...SEDGWICK...PHILLIPS... WASHINGTON...EASTERN
ELBERT AND LINCOLN COUNTIES.
TONIGHT...STORM ACTIVITY SHIFTS EAST OF THE FRONT RANGE EARLY THIS
EVENING BUT WILL LIKELY CONTINUE POSSIBLY BEYOND MIDNIGHT ON THE
FAR EASTERN PLAINS AS LOW-LEVEL MOISTURE CONTINUES TO FEED INTO
THE AREA AROUND A SFC CYCLONE IN SERN COLORADO. MODELS INDICATE
TWO AREAS WITH THE HEIGTHEN FLASH FLOOD POTENTIAL...IN THE FAR
NORTHEAST CORNER OF THE STATE AND NORTHERN LINCOLN COUNTY. DEEPER
MOISTURE...VERY SLOW STORM MOTIONS AND THE LIFT GENERATED ON THE
NOSE OF 90-110KT JET MAXIMA MAY FAVOR THE LINCOLN COUNTY AREA. BY
LATE TONIGHT...MODELS STILL SHOW LOW-LEVEL MOISTURE FEEDING INTO
NORTHEAST COLORADO AROUND A SFC LOW WHICH HAS MOVED OVER SWRN
KANSAS BY THEN. MODEL SOUNDINGS AND CROSS SECTIONS SHOW A
SATURATED BOUNDARY LAYER RIGHT UP AGAINST THE FOOTHILLS AFTER 09Z
TONIGHT. WIDESPREAD STRATUS AND AREAS OF FOG A GOOD BET ON THE
PLAINS BY DAWN AND IN SOME AREAS VISIBILITIES LESS THAN A MILE.
ON MONDAY...A RE-ENFORCING SURGE OF SOMEWHAT COOLER AND MOIST AIR
WILL SET THE STAGE FOR ANOTHER ROUND OF SEVERE T-STORMS. MODELS
SHOW A WELL DEVELOPED INSTABILITY AXIS ALIGNING WITH THE PALMER
DIVIDE FROM THE SRN FTHLS EAST TO THE KANSAS LINE. ONCE THE LOW
CLOUDS/FOG BURN OFF WHICH MAY TAKE ALL MORNING....OROGRAPHIC LIFT
AND STRONG DESTABILIZATION ALONG THE NORTH SIDE OF THE PALMER
DIVIDE COULD GENERATE MULTI-CELL FORMATION BY 20Z...AND A BIT
LATE ELSEWHERE. PLENTY OF LOW-LEVEL MOISTURE AND INSTABILITY
AROUND TO SUPPORT STRONG UPDRAFTS AND A 90-110 KT JET DIVING
SEWRD OVER THE AREA WILL PROVIDE THE NECESSARY SHEAR TO SPIN UP
ISOLATED STORMS CAPABLE OF TORNADOES ALONG STALLED OUT/OLD
OUTFLOW BOUNDARIES AROUND THE PALMER DIVIDE. AT THIS TIME IT
APPEARS THE BEST CHANCE FOR SEVERE STORMS WILL BE AFTER 21Z
TOMORROW IN THE FOLLOWING COUNTIES...ERN DOUGLAS...ELBERT...
ARAPAHOE...ERN ADAMS...WASHINGTON...SEDGWICK AND PHILLIPS.
CERTAINLY NOT OUT THE QUESTION THAT THE DENVER METRO AREA COULD
GET INTO THE ACT VERY LATE IN THE AFTERNOON. LARGE HAIL...
DAMAGING WINDS AND ISOLATED TORNADOES MAIN THREATS. STORM
PREDICTION CENTER PRESENTLY HAS VIRTUALLY ALL OF EASTERN COLORADO
IN A SLIGHT RISK FOR SEVERE WX TOMORROW. OTHERWISE...EXPECT COOLER
TEMPERATURES AREAWIDE TOMORROW WITH PASSAGE OF A DEEP UPPER
TROUGH AND ISOLATED/SCATTERED SHOWERS AND T-STORMS IN THE HIGH
COUNTRY AND ACRS PLAINS BY AFTERNOON.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 230 PM MDT SUN AUG 16 2015
UPPER LEVEL TROF AND ASSOCIATED 90+KT JET STREAK WILL SWEEP
ACROSS THE REGION MONDAY NIGHT AND TUESDAY AS QG FIELDS SHOWING
WEAK TO MODERATE ASCENT...STRONGEST OVER THE NE PLAINS. WILL
CONTINUE TO NUDGE POPS UPWARDS MONDAY EVENING WITH ABUNDANT LOW
LEVEL MOISTURE AND UPSLOPE FLOW IN PLACE. STILL A CHANCE FOR
STRONG/SEVERE STORMS CONTINUING ON THE PLAINS THROUGH MUCH OF THE
NIGHT.
FOR TUESDAY...UPPER TROF AND CLOSED LOW MOVES INTO THE UPPER MID
WEST AS STRONG QG DESCENT MOVES OVER NORTHERN COLORADO. HOWEVER IT
APPEARS A SECONDARY PUSH OF UPSLOPE AIR MOVES BACK INTO THE FRONT
RANGE WITH SHALLOW UPSLOPE FLOW AND SOME LIGHT QPF NOTED ON THE
MODELS. WILL ADJUST TEMPS DOWNWARD A BIT WHILE KEEPING HIGHER POPS
FOR THE FRONT RANGE AND PALMER DIVIDE...WHICH IS AWAY FROM THE
STRONGEST SUBSIDENCE. BETTER CLEARING BY LATE TUE NIGHT AND WED AM
AS DRIER AIRMASS MOVES IN UNDER NORTHWEST FLOW ALOFT.
FOR THURSDAY AND FRIDAY...THE FLOW ALOFT WILL BEGIN TO TURN MORE
WESTERLY WITH A SLIGHT INCREASE IN MOISTURE LEVELS. THIS WILL
RESULT IN LATE DAY ISOLATED SHOWERS AND THUNDERSTORMS MAINLY OVER
MOUNTAINS AND ADJACENT PLAINS. TEMPERATURES WILL RETURN TO MORE
NORMAL HIGHS FOR THIS TIME OF YEAR.
ANOTHER UPPER LEVEL TROF EXPECTED TO MOVE ACROSS COLORADO ON
SATURDAY WITH THE POTENTIAL FOR STORMS AND COOLER TEMPERATURES.
EUROPEAN MODEL LOOKS DEEPER WITH THIS TROF VS THE GFS BUT STILL
QUITE A WAYS OUT SO WILL JUST LEAVE ISOLATED POPS FOR NOW.
&&
.AVIATION...(FOR THE TAFS THROUGH 06Z MONDAY EVENING)
ISSUED AT 837 PM MDT SUN AUG 16 2015
MESOHIGH WAS OVER THE AREA AND HAS SWITCHED WINDS TO THE SSW AT DIA.
BOTH THE HRRR AND RAP SHOW WK SLY WINDS THRU MIDNIGHT AND THEN DVLP
A WK DENVER CYCLONE AROUND 09Z OR SO WITH WINDS BECOMING LIGHT NNW
BY 12Z. THUS MAY SEE AREAS OF FOG/LOW CLOUDS LATE TONIGHT THRU
AROUND 15Z ON MON. OVERALL THREAT OF TSTMS APPEARS TO BE DONE
HOWEVER THERE ARE A FEW SHOWERS OVER CENTRAL WELD MOVING SE BUT
THESE SHOULD STAY NORTH OF DIA.
&&
.HYDROLOGY...
ISSUED AT 250 PM MDT SUN AUG 16 2015
SLOW MOVING THUNDERSTORMS LATE THIS AFTERNOON AND EVENING OVER
AND ALONG THE FRONT RANGE AND OUT ACROSS THE NORTHEAST PLAINS WILL
BE CAPABLE OF LOCALLY HEAVY RAINS. STORMS ON THE PLAINS EAST OF
THE I-25 URBAN CORRIDOR WILL HAVE THE GREATEST POTENTIAL FOR
PRODUCING VERY HEAVY RAINFALL RESULTING IN FLASH FLOODING. A FLASH
FLOOD WATCH IS IN EFFECT FOR THE FOLLOWING...SEDGWICK...PHILLIPS...
WASHINGTON...LINCOLN AND EASTERN ELBERT COUNTIES. WATCH RUNS UNTIL
3 AM MDT TONIGHT. AS IT APPEARS NOW HEAVY RAINFALL MAY NOT
DEVELOP IN THESE COUNTIES UNTIL THIS EVENING. RAINFALL AMOUNTS
RANGING FROM 1.5 TO 3 INCHES WITHIN 1 TO 2 HOURS ARE STILL
ANTICIPATED. TRAINING OF MULTIPLE STORMS OR INTERACTIONS BETWEEN
OUTFLOW BOUNDARIES OR STRONG OUTFLOW WINDS WOULD BE NEEDED FOR
HEAVY RAINFALL IN THE FRONT RANGE FOOTHILLS AND NEARBY PLAINS.
WILL CONTINUE TO KEEP A CLOSE EYE ON STORM DEVELOPMENT DURING THE
NEXT SEVERAL HOURS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...RPK
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...RPK
HYDROLOGY...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
558 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 510 PM MDT SUN AUG 16 2015
INCREASED POPS AND CLOUDS NORTH OF I-70 AS STORM ACTIVITY IS A BIT
MORE NUMEROUS WITH THE UPPER LEVEL JET OVERHEAD AND EMBEDDED
DISTURBANCES MOVING THROUGH. VERY MINIMAL STORM COVERAGE SOUTH OF
I-70 HOWEVER. AROUND 4 PM...WE RECEIVED REPORTS OF PEA SIZE HAIL
AND BRIEF HEAVY RAIN IN YAMPA OF 0.42 INCHES IN 20 MINUTES...WHICH
IS A LITTLE OVER AN INCH AN HOUR RATES. STORMS EXHIBITED SOME
ROTATION WITH FREQUENT LIGHTNING AND SOME DECENT STORM MOTION FROM
WEST TO EAST AT 20 MPH. STORMS HAVE WEAKENED CONSIDERABLY SINCE
THEN AS STORM TOPS ARE GETTING SHEARED APART AS SEEN ON VISIBLE
SATELLITE AND LOSING THEIR UPDRAFT STRENGTH AS THEY BECOME OUTFLOW
DOMINANT. STILL FEEL INCREASE IN POPS AND CLOUDS IS WARRANTED
GIVEN THE COVERAGE AND GENERALLY FOLLOWED THE RAP MODEL FOR TRENDS
OVER THE NEXT 3 TO 6 HOURS WITH STORMS LARGELY COMING TO AN END
AFTER 9 PM WITH SOME LINGERING ACTIVITY OVER THE FAR EASTERN
PORTIONS OF OUR CWA...THE NORTHERN AND CENTRAL CO DIVIDE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 337 PM MDT SUN AUG 16 2015
ABOVE AVERAGE MOISTURE REMAINS OVER THE REGION THIS AFTERNOON AND
OVERNIGHT. SOUTH OF I-70...THE UPPER RIDGE OVER NE AZ IS
PRODUCING STRONGER SUBSIDENCE. THESE SOUTHERN STORMS WILL
INITIATE OVER THE HIGHER TERRAIN AND DRIFT SE AT 10-15 MPH. NORTH
OF I-70...A TROUGH MOVING THROUGH THE NORTHERN ROCKIES IS ALLOWING
FOR BETTER INSTABILITY. THESE STORMS WILL BE STRONGER WITH SMALL
HAIL AND A STORM MOTION TO THE ENE AT 25 MPH THAT COULD PRODUCE
STRONGER OUTFLOW WINDS.
A WEAK WAVE OFF THE NORTHERN TROUGH HAD PASSED ACROSS THE NORTHERN
ZONES THIS MORNING AND LOOKS TO BECOME STATIONARY IN THE CENTRAL
MOUNTAINS OVERNIGHT FROM THE UTAH TAVAPUTS EAST INTO THE FLAT
TOPS/ELKS/WEST ELKS. AFTER SUNSET...ISOLATED STORMS MAY CONTINUE
OVER THESE CENTRAL MOUNTAINS. TEMPERATURES ALSO IN THESE CENTRAL
ZONES SHOULD BE MILDER THAN NORMAL.
AN UPPER LEVEL LOW PRESSURE TROUGH WILL PASS OVER THE NORTHERN
ROCKIES MONDAY AFTERNOON AND BRUSH OUR FORECAST AREA DURING THE
EVENING. ALSO AN ASSOCIATED COLD FRONT WILL DROP NORTH-SOUTH ACROSS
WYOMING THROUGH THE DAY. AS A RESULT WINDS WILL INCREASE OVER THE
NORTHERN HALF DURING THE AFTERNOON. IN ADDITION...DRIER AIR WILL
BEGIN TO FILTER INTO THE NORTH. THE 18Z NAM12 SHOWS PRECIPITABLE
WATER VALUES DROPPING TO AROUND 0.25 INCH OVER NE UT/NW CO BY
EARLY EVENING. THEREFORE BETTER STORM COVERAGE IS EXPECTED TO BE
OVER THE CENTRAL TO SOUTHERN PORTION OF THE AREA. OF CONCERN OVER
NORTHWEST COLORADO WILL BE THE POSSIBILITY OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS. FOR NOW...THIS THREAT IS NOT WIDESPREAD
SO NO FIRE WEATHER HIGHLIGHTS HAVE BEEN ISSUED. SEE FIRE WEATHER
DISCUSSION BELOW.
HIGH TEMPERATURES WILL BE A TAD COOLER OVER THE NORTH WITH LITTLE
CHANGE SOUTH. LOWS WILL SEE A BIGGER COOL DOWN AS THE DRIER AND
COOLER AIR MOVES IN FROM THE NORTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 PM MDT SUN AUG 16 2015
A DRIER AND COOLER NORTHWEST FLOW WILL DEVELOP ON TUESDAY AS THE
NORTHERN LOW PRESSURE TROUGH MOVES INTO THE NORTHERN PLAINS.
ON OUR SIDE OF THE DIVIDE...THIS MORE STABLE AIR MASS WILL ALLOW
LITTLE IF ANY CONVECTION TO DEVELOP DURING THE AFTERNOON.
TEMPERATURES WILL DROP SEVERAL DEGREES...TO AROUND NORMAL OVER THE
CENTRAL PORTION...A LITTLE COOLER NORTH AND A LITTLE WARMER
SOUTH.
A SECONDARY...REINFORCING SHOT WILL SWIPE OUR NORTHEAST CORNER
TUE NIGHT. A GENERALLY DRY ZONAL FLOW WILL PERSIST THROUGH THE
WORK WEEK AS THE HIGH PRESSURE RIDGE REMAINS CENTERED OFF THE
SOUTHERN CALIFORNIA/BAJA COAST. TEMPERATURES WILL BEGIN TO REBOUND
ON THU...BUT ARE NOT EXPECTED TO REACH THE HOT READINGS WE HAVE
SEEN THE PAST FEW DAYS.
MODELS SHOW THE RIDGE AGAIN SHIFTING TO OUR SOUTH DURING THE
WEEKEND FOR A POSSIBLE RETURN OF MOISTURE. THE DETAILS IN THE
PATTERN REMAIN ELUSIVE...BUT IT APPEARS THERE WILL BE A BETTER
CHANCE OF AFTERNOON SHOWERS AND THUNDERSTORMS BEGINNING NEXT
SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 558 PM MDT SUN AUG 16 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO SWEEP
EASTWARD ACROSS AREAS ALONG AND NORTH OF THE I-70 CORRIDOR. THIS
ACTIVITY MAY DIRECTLY IMPACT KRIL...KEGE AND KASE BUT IS UNLIKELY
TO DRIVE CIGS BELOW ILS BREAKPOINTS. OUTFLOW WINDS TO 35 MPH ARE
MORE LIKELY TO AFFECT AIRPORT OPERATIONS. THIS ACTIVITY WILL
LARGELY DIMINISH BY MIDNIGHT...THOUGH A FEW SHOWERS MAY LINGER
OVER THE MOUNTAINS. THESE STORMS SHOULDN/T IMPACT TAF SITES SO
EXPECT VFR CONDITIONS TO PREVAIL THROUGH MIDDAY MONDAY.
STORMS WILL FIRE ONCE AGAIN MONDAY AFTERNOON...THOUGH COVERAGE
WILL BE REDUCED AND LARGELY CONFINED TO THE CENTRAL AND SOUTHERN
COLORADO MOUNTAINS. MEANWHILE...WINDS WILL BE INCREASING...
ESPECIALLY ACROSS THE NORTH AND ALONG THE I-70 CORRIDOR WHICH
WILL RESULT IN SOME MECHANICAL TURBULENCE AT AREA AIRPORTS.
&&
.FIRE WEATHER...
ISSUED AT 337 PM MDT SUN AUG 16 2015
WINDS WILL INCREASE OVER THE NORTH MONDAY AFTERNOON AS A UPPER
LEVEL DISTURBANCE APPROACHES THE NORTHERN ROCKIES...AND A COLD
FRONT DROPS SOUTHWARD ACROSS WYOMING. IN ADDITION DRIER AIR WILL
BEGIN TO FILTER ACROSS THE WYOMING BORDER. THIS WILL RESULT IN
BETTER COVERAGE OF DIURNAL STORMS OVER THE CENTRAL AND SOUTHERN
PORTIONS OF THE AREA. HOWEVER LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE OVER FAR NORTHWEST COLORADO...THESE
CONDITIONS ARE NOT EXPECTED TO BE WIDESPREAD. THEREFORE NO FIRE
WEATHER HIGHLIGHTS WILL BE ISSUED WITH THIS FORECAST. HOWEVER
PLEASE MONITOR THE FIRE WEATHER FORECAST FOR POSSIBLE UPDATES.
COOLER...DRIER AND MORE STABLE CONDITIONS WILL FOLLOW ON TUESDAY
ESPECIALLY OVER THE NORTH. AFTERNOON BREEZES WILL DEVELOP OVER
THE FOUR CORNERS REGION TUESDAY AFTERNOON AND BEAR WATCHING.
COOLER AND DRIER CONDITIONS WILL THEN PERSIST FOR REMAINDER OF THE
WORK WEEK...WITH WETTER CONDITIONS POSSIBLE NEXT WEEKEND.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...MDA
SHORT TERM...EH/JOE
LONG TERM...EH
AVIATION...NL
FIRE WEATHER...EH
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND JUNCTION CO
510 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 510 PM MDT SUN AUG 16 2015
INCREASED POPS AND CLOUDS NORTH OF I-70 AS STORM ACTIVITY IS A BIT
MORE NUMEROUS WITH THE UPPER LEVEL JET OVERHEAD AND EMBEDDED
DISTURBANCES MOVING THROUGH. VERY MINIMAL STORM COVERAGE SOUTH OF
I-70 HOWEVER. AROUND 4 PM...WE RECEIVED REPORTS OF PEA SIZE HAIL
AND BRIEF HEAVY RAIN IN YAMPA OF 0.42 INCHES IN 20 MINUTES...WHICH
IS A LITTLE OVER AN INCH AN HOUR RATES. STORMS EXHIBITED SOME
ROTATION WITH FREQUENT LIGHTNING AND SOME DECENT STORM MOTION FROM
WEST TO EAST AT 20 MPH. STORMS HAVE WEAKENED CONSIDERABLY SINCE
THEN AS STORM TOPS ARE GETTING SHEARED APART AS SEEN ON VISIBLE
SATELLITE AND LOSING THEIR UPDRAFT STRENGTH AS THEY BECOME OUTFLOW
DOMINANT. STILL FEEL INCREASE IN POPS AND CLOUDS IS WARRANTED
GIVEN THE COVERAGE AND GENERALLY FOLLOWED THE RAP MODEL FOR TRENDS
OVER THE NEXT 3 TO 6 HOURS WITH STORMS LARGELY COMING TO AN END
AFTER 9 PM WITH SOME LINGERING ACTIVITY OVER THE FAR EASTERN
PORTIONS OF OUR CWA...THE NORTHERN AND CENTRAL CO DIVIDE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 337 PM MDT SUN AUG 16 2015
ABOVE AVERAGE MOISTURE REMAINS OVER THE REGION THIS AFTERNOON AND
OVERNIGHT. SOUTH OF I-70...THE UPPER RIDGE OVER NE AZ IS
PRODUCING STRONGER SUBSIDENCE. THESE SOUTHERN STORMS WILL
INITIATE OVER THE HIGHER TERRAIN AND DRIFT SE AT 10-15 MPH. NORTH
OF I-70...A TROUGH MOVING THROUGH THE NORTHERN ROCKIES IS ALLOWING
FOR BETTER INSTABILITY. THESE STORMS WILL BE STRONGER WITH SMALL
HAIL AND A STORM MOTION TO THE ENE AT 25 MPH THAT COULD PRODUCE
STRONGER OUTFLOW WINDS.
A WEAK WAVE OFF THE NORTHERN TROUGH HAD PASSED ACROSS THE NORTHERN
ZONES THIS MORNING AND LOOKS TO BECOME STATIONARY IN THE CENTRAL
MOUNTAINS OVERNIGHT FROM THE UTAH TAVAPUTS EAST INTO THE FLAT
TOPS/ELKS/WEST ELKS. AFTER SUNSET...ISOLATED STORMS MAY CONTINUE
OVER THESE CENTRAL MOUNTAINS. TEMPERATURES ALSO IN THESE CENTRAL
ZONES SHOULD BE MILDER THAN NORMAL.
AN UPPER LEVEL LOW PRESSURE TROUGH WILL PASS OVER THE NORTHERN
ROCKIES MONDAY AFTERNOON AND BRUSH OUR FORECAST AREA DURING THE
EVENING. ALSO AN ASSOCIATED COLD FRONT WILL DROP NORTH-SOUTH ACROSS
WYOMING THROUGH THE DAY. AS A RESULT WINDS WILL INCREASE OVER THE
NORTHERN HALF DURING THE AFTERNOON. IN ADDITION...DRIER AIR WILL
BEGIN TO FILTER INTO THE NORTH. THE 18Z NAM12 SHOWS PRECIPITABLE
WATER VALUES DROPPING TO AROUND 0.25 INCH OVER NE UT/NW CO BY
EARLY EVENING. THEREFORE BETTER STORM COVERAGE IS EXPECTED TO BE
OVER THE CENTRAL TO SOUTHERN PORTION OF THE AREA. OF CONCERN OVER
NORTHWEST COLORADO WILL BE THE POSSIBILITY OF LOCALIZED CRITICAL
FIRE WEATHER CONDITIONS. FOR NOW...THIS THREAT IS NOT WIDESPREAD
SO NO FIRE WEATHER HIGHLIGHTS HAVE BEEN ISSUED. SEE FIRE WEATHER
DISCUSSION BELOW.
HIGH TEMPERATURES WILL BE A TAD COOLER OVER THE NORTH WITH LITTLE
CHANGE SOUTH. LOWS WILL SEE A BIGGER COOL DOWN AS THE DRIER AND
COOLER AIR MOVES IN FROM THE NORTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 PM MDT SUN AUG 16 2015
A DRIER AND COOLER NORTHWEST FLOW WILL DEVELOP ON TUESDAY AS THE
NORTHERN LOW PRESSURE TROUGH MOVES INTO THE NORTHERN PLAINS.
ON OUR SIDE OF THE DIVIDE...THIS MORE STABLE AIR MASS WILL ALLOW
LITTLE IF ANY CONVECTION TO DEVELOP DURING THE AFTERNOON.
TEMPERATURES WILL DROP SEVERAL DEGREES...TO AROUND NORMAL OVER THE
CENTRAL PORTION...A LITTLE COOLER NORTH AND A LITTLE WARMER
SOUTH.
A SECONDARY...REINFORCING SHOT WILL SWIPE OUR NORTHEAST CORNER
TUE NIGHT. A GENERALLY DRY ZONAL FLOW WILL PERSIST THROUGH THE
WORK WEEK AS THE HIGH PRESSURE RIDGE REMAINS CENTERED OFF THE
SOUTHERN CALIFORNIA/BAJA COAST. TEMPERATURES WILL BEGIN TO REBOUND
ON THU...BUT ARE NOT EXPECTED TO REACH THE HOT READINGS WE HAVE
SEEN THE PAST FEW DAYS.
MODELS SHOW THE RIDGE AGAIN SHIFTING TO OUR SOUTH DURING THE
WEEKEND FOR A POSSIBLE RETURN OF MOISTURE. THE DETAILS IN THE
PATTERN REMAIN ELUSIVE...BUT IT APPEARS THERE WILL BE A BETTER
CHANCE OF AFTERNOON SHOWERS AND THUNDERSTORMS BEGINNING NEXT
SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 1159 AM MDT SUN AUG 16 2015
SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE EAST
ACROSS THE AREA AS A WEAK DISTURBANCE ALOFT MOVES OVERHEAD.
THROUGH ABOUT 14Z KRIL...KEGE...AND KASE WILL SEE VCSH...WITH A
LESS THAN 10 PERCENT CHANCE OF VCTS AT KEGE AND KASE. MT TOPS WILL
BE LOCALLY OBSCD OVER CENTRAL CO.
ISOLD AND SCT SHOWERS AND THUNDERSTORMS WILL DEVELOP AND PERSIST
UNTIL 03Z THIS EVENING. STORMS WILL FAVOR WESTERN COLORADO
MOUNTAINS. LOCAL HEAVY RAIN AND GUSTY WINDS WILL BE THE MAIN
HAZARDS WITH A LOW CHANCE THAT THE TAF TERMINALS WILL BE BRIEFLY
IMPACTED. AFTER 03Z VFR CONDITIONS WILL DOMINATE.
&&
.FIRE WEATHER...
ISSUED AT 337 PM MDT SUN AUG 16 2015
WINDS WILL INCREASE OVER THE NORTH MONDAY AFTERNOON AS A UPPER
LEVEL DISTURBANCE APPROACHES THE NORTHERN ROCKIES...AND A COLD
FRONT DROPS SOUTHWARD ACROSS WYOMING. IN ADDITION DRIER AIR WILL
BEGIN TO FILTER ACROSS THE WYOMING BORDER. THIS WILL RESULT IN
BETTER COVERAGE OF DIURNAL STORMS OVER THE CENTRAL AND SOUTHERN
PORTIONS OF THE AREA. HOWEVER LOCALIZED CRITICAL FIRE WEATHER
CONDITIONS WILL BE POSSIBLE OVER FAR NORTHWEST COLORADO...THESE
CONDITIONS ARE NOT EXPECTED TO BE WIDESPREAD. THEREFORE NO FIRE
WEATHER HIGHLIGHTS WILL BE ISSUED WITH THIS FORECAST. HOWEVER
PLEASE MONITOR THE FIRE WEATHER FORECAST FOR POSSIBLE UPDATES.
COOLER...DRIER AND MORE STABLE CONDITIONS WILL FOLLOW ON TUESDAY
ESPECIALLY OVER THE NORTH. AFTERNOON BREEZES WILL DEVELOP OVER
THE FOUR CORNERS REGION TUESDAY AFTERNOON AND BEAR WATCHING.
COOLER AND DRIER CONDITIONS WILL THEN PERSIST FOR REMAINDER OF THE
WORK WEEK...WITH WETTER CONDITIONS POSSIBLE NEXT WEEKEND.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...MDA
SHORT TERM...EH/JOE
LONG TERM...EH
AVIATION...CC/JOE
FIRE WEATHER...EH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1120 PM MDT FRI AUG 14 2015
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 354 PM MDT FRI AUG 14 2015
CURRENTLY...
SCT STORMS WERE NOTED OVER MAINLY THE HIGHER TRRN AT 3 PM. ONE
ROUGE SHOWER WAS OVER NORTHERN BENT COUNTY. ISOLD TSRA WERE OVER
THE HIGH VALLEYS. TEMPS WERE MAINLY IN THE 90S ACROSS THE PLAINS
WITH 80S IN THE VALLEYS. LLVL MSTR IS A BIT LESS TODAY THEN PAST
DAYS...AND THIS IS EVIDENT IN THE CAPE OVER THE REGION AS VALUES
WERE LESS THAN 1000 J/KG OVER THE ENTIRE REGION.
REST OF TODAY INTO TONIGHT...
UNLIKE YDAY...HRRR HAS BEEN HAVING A BIT OF TROUBLE WITH CONVECTION
TODAY. EARLIER RUNS WERE MORE ACTIVE CONVECTIVE-WISE EARLIER IN THE
DAY...AND THIS HAS NOT HAPPENED. HRRR STILL HAS QUITE A BIT OF
ACTIVITY DEVELOPING OVER THE ENTIRE PIKES PEAK REGION LATE THIS
AFTERNOON AND EVENING...AND THIS IS STILL CONCEIVABLY POSSIBLE. FOR
NOW PLAYED UP POPS ACROSS THE PIKES PEAK REGION FOR LATER THIS
AFTERNOON AND EARLY EVENING. AS FOR THE PLAINS...BELIEVE LARGE
MAJORITY OF PLAINS (AWAY FROM THE MTNS) WILL REMAIN DRY...BUT A
ROUGE STORM CANNOT BE RULED OUT. MORE ISOLD PRECIP WILL BE OVER THE
REST OF THE HIGHER TRRN AND VALLEYS. ANY STORM OVER THE REGION TODAY
COULD PRODUCE LOCALLY HEAVY RAIN. SATELLITE WAT VAPOR IMGY STILL
SHOWS A DECENT PLUME OVER THE AREA. AREAS MOST SUSCEPTIBLE WILL BE
THE BURN SCARS AND AREAS IN WHICH IT RAINED HEAVILY LAST NIGHT.
FOR LATER THIS EVENING AND TONIGHT...BELIEVE ALL PRECIP SHOULD COME
TO AN END AS LITTLE FORCING IS AVAILABLE FOR CONVECTIVE DEVELOPMENT.
SATURDAY...
WX SHOULD BE VERY SIMILAR TO TODAYS WX AS UPPER PATTERN WILL BE
STAGNANT NEXT 24-36 HOURS AND WEAK NW FLOW WILL CONTINUE IN THE MID
LVLS OF THE ATMOSPHERE. . MOST PRECIP WILL BE TIED TO THE MTNS WITH
MOSTLY SUNNY SKIES EXPECTED OVER THE PLAINS. MAX TEMPS WILL BE
SIMILAR TO TODAYS MAX TEMPS. /HODANISH
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 354 PM MDT FRI AUG 14 2015
RELATIVELY ACTIVE METEOROLOGICAL PATTERN ANTICIPATED DURING THE
LONGER TERM WITH POPS...TEMPERATURES AND GUSTY WINDS AT TIMES
BEING PRIMARY CONCERNS.
INITIALLY...RECENT COMPUTER SIMULATIONS INDICATE THE UPPER RIDGE
CENTERED OVER CENTRAL ARIZONA SATURDAY NIGHT SETTLES OVER SOUTHERN
CALIFORNIA FROM SUNDAY NIGHT INTO AT LEAST THURSDAY...WHILE ZONAL
TO NORTHWESTERLY UPPER FLOW IS ANTICIPATED OVER THE FORECAST
DISTRICT FROM SATURDAY NIGHT INTO TUESDAY.
SOME OF THE LONGER TERM COMPUTER SIMULATIONS THEN BEGIN TO
DIVERGE WITH THE 12Z/14TH GFS40 SOLUTION SUGGESTING THAT
A RELATIVELY HEALTHY UPPER DISTURBANCE LOCATED OVER SOUTHEASTERN
MONTANA TUESDAY MORNING MOVES ACROSS WISCONSIN BY WEDNESDAY
EVENING BEFORE SHIFTING INTO QUEBEC PROVINCE CANADA BY LATER IN
THE WEEK. IN CONTRAST...THE 12Z/14TH ECMWF SOLUTION INDICATES THAT
A CLOSED UPPER LOW LOCATED OVER THE NORTHEASTERN UTAH/NORTHWESTERN
COLORADO REGION TUESDAY SHIFTS INTO SOUTHEASTERN COLORADO BY LATER
THURSDAY BEFORE PUSHING ACROSS IOWA THURSDAY EVENING.
AT THE SURFACE...SEVERAL NORTHEASTERLY TO EASTERLY SURFACE SURGES
ARE ANTICIPATED FROM SUNDAY INTO WEDNESDAY. FOR SENSIBLE
WEATHER...THE COMBINATION OF ADEQUATE TO ABUNDANT DEEPER ATMOSPHERIC
MOISTURE...SURFACE SURGES/BOUNDARIES AND UPPER LEVEL DISTURBANCES
SHOULD ALLOW ACTIVE POPS AT TIMES FROM SATURDAY EVENING INTO
MONDAY NIGHT AND POSSIBLY INTO WEDNESDAY EVENING IF THE LATEST
ECMWF SOLUTION IS ACCURATE. STORMS DURING THIS TIME-FRAME WILL BE
CAPABLE OF GENERATING LOCALLY HEAVY RAIN AND MAY BE INTENSE/STRONG
AT TIMES. THEN...WARMER AND DRIER CONDITIONS SHOULD BE NOTED BY
LATE WEEK. AS ALWAYS...WFO PUEBLO WILL MONITOR CLOSELY.
LONGER TERM TEMPERATURES OVER THE MAJORITY OF THE FORECAST
DISTRICT SHOULD GENERALLY RUN AT OR ABOVE MID-AUGUST
CLIMATOLOGICAL AVERAGES...WITH MONDAY THROUGH WEDNESDAY HAVING THE
HIGHEST POTENTIAL OF BEING NEAR TO POSSIBLY SLIGHTLY BELOW
AVERAGE. IN ADDITION...THE POTENTIAL FOR GUSTY GRADIENT WINDS MAY
ALSO BE OBSERVED AT TIMES FROM LATER TUESDAY INTO WEDNESDAY
NIGHT...PRIMARILY OVER EASTERN SECTIONS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1117 PM MDT FRI AUG 14 2015
VFR CONDITIONS EXPECTED AT THE TAF SITES OVER THE NEXT 24 HOURS.
CONVECTIVE DEBRIS CLOUDINESS WILL DECREASE OVERNIGHT WITH CLEAR
SKIES AND LIGHT WINDS EXPECTED. WINDS WILL INCREASE OUT OF THE
SOUTHEAST TO SOUTH AT KCOS AND KPUB...WHILE REMAINING LIGHT AT
KALS. ISOLATED THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS AND
PUSH EASTWARD INTO THE ADJACENT LOWER ELEVATIONS DURING THE LATE
AFTERNOON AND EVENING...WITH KCOS SEEING THE BEST CHANCE OF VCTS
NEAR THE TERMINAL. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AVIATION...KT
AREA FORECAST DISCUSSION
NWS NEW YORK NY
137 PM EDT SAT AUG 15 2015
.SYNOPSIS...
A BROAD AREA OF HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
SUNDAY. A WEAK TROUGH DISSIPATES OVER THE AREA THIS EVENING. HIGH
PRESSURE BUILDS TO THE SOUTH SUNDAY AND MERGES WITH BERMUDA HIGH
PRESSURE EARLY NEXT WEEK. THE BERMUDA HIGH THEN DOMINATES OUR
WEATHER THROUGH THURSDAY NIGHT. A COLD FRONT APPROACHES FROM THE
WEST ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE MADE SOME MINOR CHANGES TO THE FORECAST WITH THIS UPDATE.
FIRST CHANGE WAS TO INCREASE HIGHS A COUPLE DEGREES INVOF THE
NYC/NJ METRO AND ACROSS WESTERN LONG ISLAND AS 12 PM TEMPERATURES
WERE ALREADY AT PREVIOUSLY FORECAST HIGHS. LATEST FORECAST NOW
CALLS FOR A HIGH IN THE UPPER 80S ACROSS WESTERN LONG ISLAND...90
TO 91 IN NYC...AND 92-93 IN NJ METRO.
THE NEXT CHANGE WAS TO REMOVE ANY POPS ABOVE SLIGHT CHANCE ACROSS
THE INTERIOR THIS AFTERNOON AND LOWER SKY COVERAGE. LATEST
HRRR...STONY BROOK WRF...AND RAP CONTINUE TO KEEP THE REGION DRY
TODAY AS ANY SHOWER/STORM ACTIVITY THAT DEVELOPS NORTH AND WEST
STRUGGLES TO MOVE INTO THE REGION WITH INCREASING SUBSIDENCE AND
MARGINAL INSTABILITY.
HEAT INDEX VALUES WILL BE NEAR AMBIENT TEMPERATURES INVOF NYC/NJ
METRO AS DEW POINTS MIX DOWN INTO THE 50S TO NEAR 60S DEGREES.
AFTERNOON SEA BREEZES MAY HELP TO PUSH DEW POINTS A BIT HIGHER
INTO THE MIDDLE 60S...BUT TEMPERATURES WILL NOT RISE AS HIGH WITH
MARINE INFLUENCE THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
SLIGHT CHANCE POPS CONTINUE FOR ISO SHOWER/STORM...MAINLY ACROSS
INTERIOR ZONES. HAVE ALSO ADJUSTED SKY COVER DOWN TONIGHT WITH
OVERALL PARTLY CLOUDY SKIES EXPECTED.
THE UPPER TROUGH MOVES EAST OF THE NEW ENGLAND COAST THIS EVENING
WITH RIDGING BUILDING IN THROUGH SUNDAY AS HEIGHT CONTINUE TO RISE.
HAVE REMOVED THE CHANCE FOR ANY THUNDERSTORMS SUNDAY AFTERNOON AS
SUBSIDENCE INCREASES AND LOW LEVEL DRYING OCCURS WITH BOUNDARY LAYER
MIXING IN THE AFTERNOON. INLAND TEMPERATURES RISE INTO THE LOWER TO
MID 90S SUNDAY WITH COASTAL AREAS COOLER WITH A MARINE INFLUENCE AS
SEAS BREEZES DEVELOPING. USED A BLEND OF THE GUIDANCE TEMPERATURES
FOR LOWS AND HIGHS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE REGION REMAINS IN BETWEEN A WESTWARD EXTENSION OF THE SUB
TROPICAL RIDGE AND MEAN TROUGHING OVER THE CENTRAL PLAINS/MIDWEST
SUNDAY THROUGH THURSDAY. MONDAY AFTERNOON EXPECTED TO BE DRY AS
STRONG SUBSIDENCE REMAINS AND AND TROUGHS REMAIN TO THE WEST. WILL
HAVE VARIOUS WEAK SHORTWAVE RIDGES AND TROUGHS PASS BY THROUGH THE
AREA TUESDAY THROUGH THURSDAY ON A MEAN SW FLOW ALOFT. THIS PATTERN
SUNDAY-THURSDAY NIGHT DICTATES ISOLD-SCT AFTERNOON/EVENING
SHRA/TSTMS MAINLY OVER THE NW 1/2 OF THE CWA TUESDAY THROUGH
THURSDAY.
WHILE THERE ARE DIFFERENCES IN TIMING/STRENGTH BETWEEN THE VARIOUS
MODELS THERE IS GENERAL AGREEMENT THAT A NORTHERN STREAM SHORTWAVE
WILL PASS MAINLY TO THE N AROUND FRIDAY. AS A RESULT HAVE CHANCE
SHRA/TSTMS THEN WITH AN EXPECTATION OF SLIGHTLY STRONGER FORCING CWA
WIDE.
TEMPERATURES SUNDAY NIGHT-FRIDAY...
FOR HIGHS SUNDAY A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 900-825 HPA PER BUFKIT SOUNDINGS
WAS USED. HIGHS SHOULD BE 5-10 DEGREES ABOVE NORMAL - MAINLY FROM
THE UPPER 80S-LOWER 90S...WITH SOME MID 90S POSSIBLE IN URBAN NE NJ.
FOR NOW IT APPEARS AFTERNOON HEAT INDICES WILL BE NEAR OR JUST BELOW
THE AIR TEMPERATURE...SO BELOW ADVISORY CRITERIA.
A BLEND OF MET AND MAV GUIDANCE WITH NAM 2-METER TEMPERATURES WAS
USED FOR LOWS SUNDAY NIGHT...WITH VALUES FORECAST TO BE AROUND 5
DEGREES ABOVE NORMAL. A BLEND OF MEX/MEN/ECE/ECM GUIDANCE...NAM 2-
METER TEMPERATURES AND A MIX DOWN FROM 975-825 HPA PER BUFKIT
SOUNDINGS WAS USED FOR HIGHS ON MONDAY WITH VALUES FORECAST TO BE
AROUND 10 DEGREES ABOVE NORMAL - GENERALLY A DEGREE OR TWO WARMER
THAN ON SUNDAY. AFTERNOON HEAT INDICES COULD REACH THE MIDDLE 90S IN
URBAN AREAS.
FROM MONDAY NIGHT-FRIDAY A BLEND OF MEX/MEN/ECE/ECM/WPC GUIDANCE WAS
USED FOR TEMPERATURES...WITH CONTINUED VERY WARM TO HOT CONDITIONS
ACROSS THE REGION. FOR NOW FORECASTING AFTERNOON HEAT INDICES TO
GENERALLY PEAK OUT IN THE UPPER 80S TO LOWER 90S AWAY FROM THE
IMMEDIATE COASTS...WHICH IS NEAR OR JUST BELOW THE FORECAST AIR
TEMPERATURES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
A BROAD AREA OF HI PRES WILL REMAIN OVER THE REGION THRU THE
WEEKEND.
SW-S FLOW TODAY...GENERALLY AOB 10KT. STRONGER FLOW AT KJFK WITH
SEA BREEZE ENHANCEMENT. SEA BREEZE PROBABLY REACHES KLGA LATE
AFTN AND PROBABLY REMAINS EAST OF KEWR AND KTEB FOR THE REST OF
THE DAY.
VFR. SLIGHT CHC SHRA/TSTM WITH BRIEF MVFR AT KSWF LATE AFTN/EARLY
EVE.
.OUTLOOK FOR 18Z SUN THROUGH THU...
.SUN PM...VFR WITH SW-S WINDS.
.MON...VFR. SW-S WINDS.
.TUE...VFR OUTSIDE OF SCT-ISOLD AFTN/EVE TSTMS. S WINDS.
.WED...AREAS OF MVFR OR LOWER POSSIBLE. S WINDS.
.THU...CHC SHRA/TSTMS WITH MVFR OR LOWER POSSIBLE. S WINDS.
&&
.MARINE...
WIND AND SEAS FORECAST ON TRACK...NO CHANGES AT THIS TIME.
SW FLOW THIS WEEKEND. WINDS WILL BACK TO THE S THIS AFTN OVER THE
WRN OCEAN AND INVOF THE HARBOR ENTRANCE DUE TO THE SEA BREEZE
CIRCULATION. OCNL GUSTS UP TO 25 KT CANNOT BE RULED OUT IN THIS
AREA. OTHERWISE...WINDS AND SEAS BLW SCA LVLS THIS WEEKEND.
WINDS AND SEAS BLW SCA LVLS MON-WED WITH A LARGE AREA OF HI PRES
OVER THE ERN SEABOARD.
&&
.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD RAINFALL EXPECTED THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DS/MET
NEAR TERM...DS/MET
SHORT TERM...DS/MET
LONG TERM...MALOIT/MET
AVIATION...JC
MARINE...JMC
HYDROLOGY...MET
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1230 PM EDT SAT AUG 15 2015
.SYNOPSIS...
A BROAD AREA OF HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
SUNDAY. A WEAK TROUGH DISSIPATES OVER THE AREA THIS EVENING. HIGH
PRESSURE BUILDS TO THE SOUTH SUNDAY AND MERGES WITH BERMUDA HIGH
PRESSURE EARLY NEXT WEEK. THE BERMUDA HIGH THEN DOMINATES OUR
WEATHER THROUGH THURSDAY NIGHT. A COLD FRONT APPROACHES FROM THE
WEST ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE MADE SOME MINOR CHANGES TO THE FORECAST WITH THIS UPDATE.
FIRST CHANGE WAS TO INCREASE HIGHS A COUPLE DEGREES INVOF THE
NYC/NJ METRO AND ACROSS WESTERN LONG ISLAND AS 12 PM TEMPERATURES
WERE ALREADY AT PREVIOUSLY FORECAST HIGHS. LATEST FORECAST NOW
CALLS FOR A HIGH IN THE UPPER 80S ACROSS WESTERN LONG ISLAND...90
TO 91 IN NYC...AND 92-93 IN NJ METRO.
THE NEXT CHANGE WAS TO REMOVE ANY POPS ABOVE SLIGHT CHANCE ACROSS
THE INTERIOR THIS AFTERNOON AND LOWER SKY COVERAGE. LATEST
HRRR...STONY BROOK WRF...AND RAP CONTINUE TO KEEP THE REGION DRY
TODAY AS ANY SHOWER/STORM ACTIVITY THAT DEVELOPS NORTH AND WEST
STRUGGLES TO MOVE INTO THE REGION WITH INCREASING SUBSIDENCE AND
MARGINAL INSTABILITY.
HEAT INDEX VALUES WILL BE NEAR AMBIENT TEMPERATURES INVOF NYC/NJ
METRO AS DEW POINTS MIX DOWN INTO THE 50S TO NEAR 60S DEGREES.
AFTERNOON SEA BREEZES MAY HELP TO PUSH DEW POINTS A BIT HIGHER
INTO THE MIDDLE 60S...BUT TEMPERATURES WILL NOT RISE AS HIGH WITH
MARINE INFLUENCE THERE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
SLIGHT CHANCE POPS CONTINUE FOR ISO SHOWER/STORM...MAINLY ACROSS
INTERIOR ZONES. HAVE ALSO ADJUSTED SKY COVER DOWN TONIGHT WITH
OVERALL PARTLY CLOUDY SKIES EXPECTED.
THE UPPER TROUGH MOVES EAST OF THE NEW ENGLAND COAST THIS EVENING
WITH RIDGING BUILDING IN THROUGH SUNDAY AS HEIGHT CONTINUE TO RISE.
HAVE REMOVED THE CHANCE FOR ANY THUNDERSTORMS SUNDAY AFTERNOON AS
SUBSIDENCE INCREASES AND LOW LEVEL DRYING OCCURS WITH BOUNDARY LAYER
MIXING IN THE AFTERNOON. INLAND TEMPERATURES RISE INTO THE LOWER TO
MID 90S SUNDAY WITH COASTAL AREAS COOLER WITH A MARINE INFLUENCE AS
SEAS BREEZES DEVELOPING. USED A BLEND OF THE GUIDANCE TEMPERATURES
FOR LOWS AND HIGHS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE REGION REMAINS IN BETWEEN A WESTWARD EXTENSION OF THE SUB
TROPICAL RIDGE AND MEAN TROUGHING OVER THE CENTRAL PLAINS/MIDWEST
SUNDAY THROUGH THURSDAY. MONDAY AFTERNOON EXPECTED TO BE DRY AS
STRONG SUBSIDENCE REMAINS AND AND TROUGHS REMAIN TO THE WEST. WILL
HAVE VARIOUS WEAK SHORTWAVE RIDGES AND TROUGHS PASS BY THROUGH THE
AREA TUESDAY THROUGH THURSDAY ON A MEAN SW FLOW ALOFT. THIS PATTERN
SUNDAY-THURSDAY NIGHT DICTATES ISOLD-SCT AFTERNOON/EVENING
SHRA/TSTMS MAINLY OVER THE NW 1/2 OF THE CWA TUESDAY THROUGH
THURSDAY.
WHILE THERE ARE DIFFERENCES IN TIMING/STRENGTH BETWEEN THE VARIOUS
MODELS THERE IS GENERAL AGREEMENT THAT A NORTHERN STREAM SHORTWAVE
WILL PASS MAINLY TO THE N AROUND FRIDAY. AS A RESULT HAVE CHANCE
SHRA/TSTMS THEN WITH AN EXPECTATION OF SLIGHTLY STRONGER FORCING CWA
WIDE.
TEMPERATURES SUNDAY NIGHT-FRIDAY...
FOR HIGHS SUNDAY A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 900-825 HPA PER BUFKIT SOUNDINGS
WAS USED. HIGHS SHOULD BE 5-10 DEGREES ABOVE NORMAL - MAINLY FROM
THE UPPER 80S-LOWER 90S...WITH SOME MID 90S POSSIBLE IN URBAN NE NJ.
FOR NOW IT APPEARS AFTERNOON HEAT INDICES WILL BE NEAR OR JUST BELOW
THE AIR TEMPERATURE...SO BELOW ADVISORY CRITERIA.
A BLEND OF MET AND MAV GUIDANCE WITH NAM 2-METER TEMPERATURES WAS
USED FOR LOWS SUNDAY NIGHT...WITH VALUES FORECAST TO BE AROUND 5
DEGREES ABOVE NORMAL. A BLEND OF MEX/MEN/ECE/ECM GUIDANCE...NAM 2-
METER TEMPERATURES AND A MIX DOWN FROM 975-825 HPA PER BUFKIT
SOUNDINGS WAS USED FOR HIGHS ON MONDAY WITH VALUES FORECAST TO BE
AROUND 10 DEGREES ABOVE NORMAL - GENERALLY A DEGREE OR TWO WARMER
THAN ON SUNDAY. AFTERNOON HEAT INDICES COULD REACH THE MIDDLE 90S IN
URBAN AREAS.
FROM MONDAY NIGHT-FRIDAY A BLEND OF MEX/MEN/ECE/ECM/WPC GUIDANCE WAS
USED FOR TEMPERATURES...WITH CONTINUED VERY WARM TO HOT CONDITIONS
ACROSS THE REGION. FOR NOW FORECASTING AFTERNOON HEAT INDICES TO
GENERALLY PEAK OUT IN THE UPPER 80S TO LOWER 90S AWAY FROM THE
IMMEDIATE COASTS...WHICH IS NEAR OR JUST BELOW THE FORECAST AIR
TEMPERATURES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
A BROAD AREA OF HI PRES WILL REMAIN OVER THE REGION THRU THE
WEEKEND.
SW FLOW TODAY...GENERALLY AOB 10KT. STRONGER FLOW THIS AFTN KJFK
WITH SEA BREEZE ENHANCEMENT AND WINDS BACKED TO THE S.
MAINLY VFR THRU THE TAF PERIOD. THERE COULD BE A FEW AFTN/EVE
SHWRS AND TSTMS...BUT COVERAGE TOO LOW TO INCLUDE IN THE TAFS.
MOST PROBABLE AREAS FOR THIS ACTIVITY N AND W OF THE CITY
TERMINALS.
.OUTLOOK FOR 12Z SUN THROUGH WED...
.SUN...VFR WITH SW FLOW.
.MON...VFR OUTSIDE OF SCT-ISOLD AFTN/EVE TSTMS. SW WINDS.
.TUE...VFR OUTSIDE OF SCT-ISOLD AFTN/EVE TSTMS. S FLOW.
.WED...AREAS OF MVFR OR LOWER POSSIBLE. S FLOW.
&&
.MARINE...
WIND AND SEAS FORECAST ON TRACK...NO CHANGES AT THIS TIME.
SW FLOW THIS WEEKEND. WINDS WILL BACK TO THE S THIS AFTN OVER THE
WRN OCEAN AND INVOF THE HARBOR ENTRANCE DUE TO THE SEA BREEZE
CIRCULATION. OCNL GUSTS UP TO 25 KT CANNOT BE RULED OUT IN THIS
AREA. OTHERWISE...WINDS AND SEAS BLW SCA LVLS THIS WEEKEND.
WINDS AND SEAS BLW SCA LVLS MON-WED WITH A LARGE AREA OF HI PRES
OVER THE ERN SEABOARD.
&&
.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD RAINFALL EXPECTED THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DS/MET
NEAR TERM...DS/MET
SHORT TERM...DS/MET
LONG TERM...MALOIT/MET
AVIATION...JMC/JC
MARINE...JMC
HYDROLOGY...MET
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1004 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A BROAD AREA OF HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH
SUNDAY. A WEAK TROUGH DISSIPATES OVER THE AREA THIS EVENING. HIGH
PRESSURE BUILDS TO THE SOUTH SUNDAY AND MERGES WITH BERMUDA HIGH
PRESSURE EARLY NEXT WEEK. THE BERMUDA HIGH THEN DOMINATES OUR
WEATHER THROUGH THURSDAY NIGHT. A COLD FRONT APPROACHES FROM THE
WEST ON FRIDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST REMAINS ON TRACK. UPDATED HOURLY GRIDS TO REFLECT THE
LATEST TRENDS IN OBSERVATIONS.
SURFACE AND UPPER LEVEL TROUGH ARE LOCATED ACROSS UPSTATE NY TO
THE OHIO VALLEY. THESE WILL BE WEAKENING THROUGH THE DAY AS
HEIGHTS RISE AND SUBSIDENCE INCREASES ACROSS THE REGION.
LATEST HRRR...STONY BROOK WRF...AND RAP KEEP THE REGION DRY TODAY
AS ANY SHOWER/STORM ACTIVITY THAT DEVELOPS NORTH AND WEST
STRUGGLES TO MOVE INTO THE REGION WITH INCREASING SUBSIDENCE AND
MARGINAL INSTABILITY. WILL CONTINUE WITH MAINLY SLIGHT CHANCE POPS
FOR ISO SHOWER/STORM...BUT EVEN THIS MAY BE A BIT OVERDONE DUE TO
THE AFOREMENTIONED INHIBITING FACTORS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/...
THE UPPER TROUGH MOVES EAST OF THE NEW ENGLAND COAST THIS EVENING
WITH RIDGING BUILDING IN THROUGH SUNDAY AS HEIGHT CONTINUE TO RISE.
HAVE REMOVED THE CHANCE FOR ANY THUNDERSTORMS SUNDAY AFTERNOON AS
SUBSIDENCE INCREASES AND LOW LEVEL DRYING OCCURS WITH BOUNDARY LAYER
MIXING IN THE AFTERNOON. INLAND TEMPERATURES RISE INTO THE LOWER TO
MID 90S SUNDAY WITH COASTAL AREAS COOLER WITH A MARINE INFLUENCE AS
SEAS BREEZES DEVELOPING. USED A BLEND OF THE GUIDANCE TEMPERATURES
FOR LOWS AND HIGHS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE REGION REMAINS IN BETWEEN A WESTWARD EXTENSION OF THE SUB
TROPICAL RIDGE AND MEAN TROUGHING OVER THE CENTRAL PLAINS/MIDWEST
SUNDAY THROUGH THURSDAY. MONDAY AFTERNOON EXPECTED TO BE DRY AS
STRONG SUBSIDENCE REMAINS AND AND TROUGHS REMAIN TO THE WEST. WILL
HAVE VARIOUS WEAK SHORTWAVE RIDGES AND TROUGHS PASS BY THROUGH THE
AREA TUESDAY THROUGH THURSDAY ON A MEAN SW FLOW ALOFT. THIS PATTERN
SUNDAY-THURSDAY NIGHT DICTATES ISOLD-SCT AFTERNOON/EVENING
SHRA/TSTMS MAINLY OVER THE NW 1/2 OF THE CWA TUESDAY THROUGH
THURSDAY.
WHILE THERE ARE DIFFERENCES IN TIMING/STRENGTH BETWEEN THE VARIOUS
MODELS THERE IS GENERAL AGREEMENT THAT A NORTHERN STREAM SHORTWAVE
WILL PASS MAINLY TO THE N AROUND FRIDAY. AS A RESULT HAVE CHANCE
SHRA/TSTMS THEN WITH AN EXPECTATION OF SLIGHTLY STRONGER FORCING CWA
WIDE.
TEMPERATURES SUNDAY NIGHT-FRIDAY...
FOR HIGHS SUNDAY A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM 2-METER
TEMPERATURES AND A MIX DOWN FROM 900-825 HPA PER BUFKIT SOUNDINGS
WAS USED. HIGHS SHOULD BE 5-10 DEGREES ABOVE NORMAL - MAINLY FROM
THE UPPER 80S-LOWER 90S...WITH SOME MID 90S POSSIBLE IN URBAN NE NJ.
FOR NOW IT APPEARS AFTERNOON HEAT INDICES WILL BE NEAR OR JUST BELOW
THE AIR TEMPERATURE...SO BELOW ADVISORY CRITERIA.
A BLEND OF MET AND MAV GUIDANCE WITH NAM 2-METER TEMPERATURES WAS
USED FOR LOWS SUNDAY NIGHT...WITH VALUES FORECAST TO BE AROUND 5
DEGREES ABOVE NORMAL. A BLEND OF MEX/MEN/ECE/ECM GUIDANCE...NAM 2-
METER TEMPERATURES AND A MIX DOWN FROM 975-825 HPA PER BUFKIT
SOUNDINGS WAS USED FOR HIGHS ON MONDAY WITH VALUES FORECAST TO BE
AROUND 10 DEGREES ABOVE NORMAL - GENERALLY A DEGREE OR TWO WARMER
THAN ON SUNDAY. AFTERNOON HEAT INDICES COULD REACH THE MIDDLE 90S IN
URBAN AREAS.
FROM MONDAY NIGHT-FRIDAY A BLEND OF MEX/MEN/ECE/ECM/WPC GUIDANCE WAS
USED FOR TEMPERATURES...WITH CONTINUED VERY WARM TO HOT CONDITIONS
ACROSS THE REGION. FOR NOW FORECASTING AFTERNOON HEAT INDICES TO
GENERALLY PEAK OUT IN THE UPPER 80S TO LOWER 90S AWAY FROM THE
IMMEDIATE COASTS...WHICH IS NEAR OR JUST BELOW THE FORECAST AIR
TEMPERATURES.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
A BROAD AREA OF HI PRES WILL REMAIN OVER THE REGION THRU THE
WEEKEND.
SW FLOW TODAY...GENERALLY AOB 10KT. STRONGER FLOW THIS AFTN KJFK
WITH SEA BREEZE ENHANCEMENT AND WINDS BACKED TO THE S.
MAINLY VFR THRU THE TAF PERIOD. THERE COULD BE A FEW AFTN/EVE
SHWRS AND TSTMS...BUT COVERAGE TOO LOW TO INCLUDE IN THE TAFS.
MOST PROBABLE AREAS FOR THIS ACTIVITY N AND W OF THE CITY
TERMINALS.
.OUTLOOK FOR 12Z SUN THROUGH WED...
.SUN...VFR WITH SW FLOW.
.MON...VFR OUTSIDE OF SCT-ISOLD AFTN/EVE TSTMS. SW WINDS.
.TUE...VFR OUTSIDE OF SCT-ISOLD AFTN/EVE TSTMS. S FLOW.
.WED...AREAS OF MVFR OR LOWER POSSIBLE. S FLOW.
&&
.MARINE...
WIND AND SEAS FORECAST ON TRACK...NO CHANGES AT THIS TIME.
SW FLOW THIS WEEKEND. WINDS WILL BACK TO THE S THIS AFTN OVER THE
WRN OCEAN AND INVOF THE HARBOR ENTRANCE DUE TO THE SEA BREEZE
CIRCULATION. OCNL GUSTS UP TO 25 KT CANNOT BE RULED OUT IN THIS
AREA. OTHERWISE...WINDS AND SEAS BLW SCA LVLS THIS WEEKEND.
WINDS AND SEAS BLW SCA LVLS MON-WED WITH A LARGE AREA OF HI PRES
OVER THE ERN SEABOARD.
&&
.HYDROLOGY...
NO SIGNIFICANT WIDESPREAD RAINFALL EXPECTED THROUGH THE MIDDLE OF
NEXT WEEK.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MET
NEAR TERM...DS/MET
SHORT TERM...MET
LONG TERM...MALOIT/MET
AVIATION...JMC
MARINE...JMC
HYDROLOGY...MET
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
726 PM EDT SUN AUG 16 2015
.UPDATE...
MADE A FEW CHANGES TO THE FORECAST...MAINLY TO POPS FOR OVERNIGHT
INTO TOMORROW. THE NAM SHOWS A WEAK WAVE MOVING THROUGH
TONIGHT...AND THE HRRR DOES DEVELOP SOME SHOWERS WITH THIS
FEATURE. CURRENTLY...THE BEST TIMING FOR THESE SHOWERS LOOKS TO BE
RIGHT BEFORE DAWN. NOT TOO CONFIDENT ON THE COVERAGE...SO KEPT
POPS CAPPED AROUND 30-40 PERCENT. ALSO TWEAKED THE TIMING FOR THE
AFTERNOON SHRA/TSRA FOR TOMORROW AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 335 PM EDT SUN AUG 16 2015/
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AIRMASS IS MODIFYING WITH A MORNING SOUNDING SHOWING 1.5 PWS AND
OVER 3500 MUCAPE... ALL WITH NO CAP. THE GREATER AFTERNOON STORM
CHANCES WILL BE ACROSS FAR NORTH GA WHERE AN UPPER TROUGH IS NEARER
TO NW GA AND OROGRAPHIC LIFT WILL ENHANCE CONVECTION IN THE
MOUNTAINS... AND ACROSS CENTRAL GA WHERE DEEP ATLANTIC MOISTURE IS
ON THE INCREASE. REGIONAL RADARS ARE SHOWING SCATTERED TO NUMEROUS
SHOWERS WITH SOME EMBEDDED THUNDERSTORMS ALREADY DEVELOPING ACROSS
CENTRAL GA... MAINLY ALONG AND SOUTH OF A FRANKLIN TO LOUISVILLE
LINE AND DRIFTING NORTHWARD. AIRMASS WOULD SUPPORT DEVELOPMENT JUST
ABOUT ANYWHERE... SO HAVE INCREASED POPS THROUGH THE EVENING FOR
MOST AREAS... WITH LIKELY POPS ACROSS MUCH OF CENTRAL GA. ALTHOUGH
STORMS ARE EXPECTED TO REMAIN BELOW SEVERE LIMITS WITH LITTLE SHEAR
OR FORCING NOTED... CANNOT RULE OUT A FEW STRONG STORMS BETWEEN 4-9
PM TODAY. THE THUNDERSTORM THREAT SHOULD END BY 9 PM THIS EVENING...
BUT ISOLATED TO POSSIBLY SCATTERED SHOWERS COULD LINGER OVERNIGHT.
THIS IS LARGELY DUE TO AN UPPER TROUGH ALONG THE MS VALLEY REGION
THAT WILL BEGIN TO DRIFT EASTWARD TONIGHT... AND PROVIDE AN SUPPORT
FOR INCREASING RAIN CHANCES FROM THE WEST BEGINNING MONDAY
MORNING... THEN BECOMING SCATTERED TO NUMEROUS IN COVERAGE FOR MOST
AREAS BY MID MONDAY AFTERNOON. NOT EXPECTING SEVERE STORMS ON
MONDAY... BUT A FEW STORMS COULD BE STRONG MONDAY AFTERNOON WITH
WIND GUSTS TO 45 MPH AND FREQUENT LIGHTNING BEING THE MAIN THREATS.
HIGH PWS WOULD ALSO SUPPORT LOCALLY HEAVY RAIN AND BRIEF PONDING OF
WATER IS LIKELY ACROSS LOW LYING AREAS. SCATTERED CONVECTION IS
EXPECTED TO CONTINUE ACROSS THE AREA MONDAY NIGHT... BUT MOSTLY IN
THE FORM OF SHOWERS.
ALTHOUGH A FEW SHOWERS WILL BE POSSIBLY TONIGHT... EXPECTING LOW
CLOUDS AND PATCHY FOG TO DEVELOP ACROSS CENTRAL GA AND SPREAD
NORTHWARD TOWARD MONDAY MORNING. THIS WILL HELP HOLD TEMPS AND
INSTABILITIES DOWN ON MONDAY... ALL SUPPORTING A LESSOR CHANCE FOR
SEVERE STORMS.
OTHERWISE... A MAV AND MET BLEND GAVE NEAR NORMAL TEMPS THROUGH THE
FORECAST PERIOD... WHICH LOOKS REASONABLE... SO DID NOT STRAY.
39
LONG TERM /TUESDAY THROUGH SUNDAY/...
NO CHANGES MADE TO THE EXTENDED FORECAST. DEEP MOISTURE ASSOCIATED
WITH SW FLOW ALOFT WILL BE ACROSS THE AREA TO START THE LONG TERM
WITH RATHER HIGH PRECIPITATION CHANCES TUESDAY. EVEN THOUGH AN
UPPER RIDGE BUILDS SLIGHTLY OVER S GA ON WEDNESDAY...A MOIST
AIRMASS WILL CONTINUE FROM SW FLOW ALOFT. THE UPPER RIDGE
CONTINUES TO BUILD ON THURSDAY WITH THE SW FLOW ALOFT BECOMING
WEAKER BUT A MOIST AIRMASS CONTINUES OVER THE AREA...MOST SO ON
THE GFS AND LESS SO ON THE EUROPEAN. THE UPPER RIDGE CONTINUES TO
BUILD FRIDAY AND SATURDAY WITH A RATHER MOIST AIRMASS CONTINUING
ALLOWING FOR AT LEAST A CHANCE OF SHOWERS AND THUNDERSTORMS EACH
DAY.
FORECAST LOW TEMPERATURES EXPECTED TO BE AROUND NORMAL AND FORECAST HIGH
TEMPERATURES START OUT BELOW NORMAL BUT ARE EXPECTED TO WARM AROUND
NORMAL TOWARD WEEKS END.
BDL/01
&&
.AVIATION...
00Z UPDATE...
WINDS WILL REMAIN ON THE EAST SIDE THROUGH THE VALID TAF PERIOD.
HOWEVER...MODELS ARE PROGGING A SWITCH TO THE SW JUST AFTER 06Z
TUE. HRRR IS PROGGING SOME LIGHT SHOWERS POSSIBLY AFFECTING THE
AIRFIELD EARLY MONDAY MORNING SO HAVE ADDED A VCSH STARTING AT 10Z
WITH THE MVFR CIGS. SHOWERS WILL HANG AROUND PRETTY MUCH ALL DAY.
THE BEST TIMING FOR ANY THUNDER WILL BE DURING THE AFTERNOON AND
EARLY EVENING.
//ATL CONFIDENCE...00Z UPDATE...
MED CONFIDENCE ALL ELEMENTS.
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 71 87 71 86 / 20 50 60 70
ATLANTA 73 85 73 85 / 40 60 60 70
BLAIRSVILLE 65 80 66 79 / 30 60 70 70
CARTERSVILLE 70 85 70 85 / 40 60 70 70
COLUMBUS 73 88 74 89 / 40 60 50 70
GAINESVILLE 71 83 71 82 / 20 60 60 70
MACON 72 88 73 89 / 30 60 60 70
ROME 71 84 71 85 / 40 60 70 70
PEACHTREE CITY 71 85 71 86 / 40 60 60 70
VIDALIA 72 89 73 89 / 30 50 50 70
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
933 PM CDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 928 PM CDT SUN AUG 16 2015
CONCERN THIS EVENING REMAINS FLASH FLOOD POTENTIAL. RADAR
ESTIMATES AND OBSERVATIONS INDICATE PORTIONS OF ABOUT FOUR NW/N
CENTRAL COUNTIES HAVE SEEN TWO TO THREE INCHES OF RAINFALL
ALREADY. PWATS AND WARM CLOUD DEPTHS ARE ALL QUITE FAVORABLE FOR
VERY EFFICIENT RAINS BUT WEAKENING INSTABILITY WITH LOSS OF
HEATING WILL MAKE IT DIFFICULT TO REALIZE THESE CONDITIONS ON A
WIDESPREAD BASIS. WITH ONE HOUR FLASH FLOOD GUIDANCE PUSHING 2.50
INCHES...MOST LOCATIONS CAN TAKE ONE EVENT WITH 2-3 EVENTS NEEDED
TO GET TO FLASH FLOOD CRITERIA. RAP 305K ISENT MOISTURE
CONVERGENCE SUGGESTS RECENT POST FRONTAL CONVECTIVE DEVELOPMENT
OVER NW IA WILL CONTINUE THROUGH MIDNIGHT...BUT HAVE OPTED FOR
TARGETED SPS ISSUANCES RATHER THAN MORE WIDESPREAD FLASH FLOOD
WATCH FOR REASONS ALSO NOTED IN SHORT TERM SECTIONS BELOW.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 329 PM CDT SUN AUG 16 2015
SFC COLD FRONT IS SINKING SLOWLY THROUGH SOUTHEAST SOUTH DAKOTA AND
SOUTHWEST MINNESOTA THIS AFTERNOON. A WEAK UPPER RIDGE REMAINS
STRETCHED THROUGH CENTRAL IOWA AND IS SEPARATING THE MUCH DRIER AIR
TO THE SOUTHEAST FROM THE DEEPER MOISTURE TO THE WEST AND NORTHWEST
OF THE SYSTEM. THE RIDGE WILL SHIFT SOUTHEAST AND WEAKEN FURTHER
OVERNIGHT ALLOWING THE SFC BOUNDARY TO ENTER NORTHERN IOWA. THE
OVERALL FORCING AND INSTABILITY OVERNIGHT IS LIMITED AND DESPITE A
RELATIVELY WEAK LOW LEVEL JET...THE MOISTURE TRANSPORT LIFTING INTO
THE BOUNDARY IS GOOD AND WILL HELP PUSH PWATS TO NEAR 2 INCHES OVER
NORTHERN IOWA. WARM CLOUD DEPTHS AROUND 13 KFT ARE SUPPORTIVE OF AN
EFFICIENT RAIN PRODUCING ENVIRONMENT AND MEAN STORM MOTIONS ARE
CLOSE TO PARALLEL TO THE SFC BOUNDARY LEADING TO THE POTENTIAL FOR
TRAINING STORMS.
GIVEN ALL OF THE ABOVE...DO EXPECT SOME AREAS WITH HEAVY RAINFALL
POSSIBLY EXCEEDING 3 INCHES. PLANNING TO HOLD OFF ON A FLASH FLOOD
WATCH AT THIS TIME FOR A VARIETY OF REASONS. MUCH OF NORTHERN IOWA
NORTH OF HIGHWAY 20 HAVE HAD ONE HALF INCH OR LESS OF PRECIPITATION
FOR AUGUST. THE CROPS ARE NEARING FULL MATURATION AND LIMIT RUNOFF
RATES AND THE AREA WITH THE GREATEST THREAT FOR HEAVY RAIN OVER THE
FAR NORTHWEST ARE CLIMATOLOGICALLY DIFFICULT TO FLASH FLOOD DUE TO
THE LANDSCAPE. WILL MENTION LOCALIZED FLASH FLOODING POSSIBLE IN THE
HWO. SHOULD THE THREAT FOR HIGHER QPF ARISE...THEN HEADLINES MAY BE
REQUIRED. THE SEVERE WEATHER THREAT IS LOW...GIVEN THE DEEPER WARM
CLOUD DEPTHS AND SATURATED PROFILES...THE HAIL THREAT WILL BE LOW
LEAVING AN ISOLATED DAMAGING WIND GUST AS THE PRIMARY SEVERE THREAT.
.LONG TERM /MONDAY THROUGH SUNDAY/...
ISSUED AT 329 PM CDT SUN AUG 16 2015
CURRENTLY HAVE AN AREA OF LOW PRESSURE CENTERED ACROSS SRN MANITOBA
AND SASKATCHEWAN...THIS WILL PUSH INTO SOUTHERN ONTARIO SUNDAY
EVENING WITH THE ASSOCIATED COLD FRONT TO PUSH INTO NORTHWESTERN
IOWA AND THE NORTHWESTERN CWA BY LATE SUNDAY. THE FRONTAL BOUNDARY
WILL CONTINUE TO PUSH SOUTHWARD ACROSS THE CWA...STALLING OUT ACROSS
THE AREA BY LATER MONDAY INTO TUESDAY. THIS WILL ALLOW FOR AN
EXTENDED PERIOD OF RAIN CHANCES BEGINNING MAINLY LATE SUNDAY
AFTERNOON NORTHWEST AND SPREADING ACROSS THE CWA SUNDAY NIGHT INTO
MONDAY. THETA-E ADVECTION BETTER ACROSS THE NORTH INTO THE
EVENING...WITH MOISTURE CONVERGENCE INCREASING ALONG THE FRONT INTO
THE LATE NIGHT HOURS. WITH THE GRADUAL MOVEMENT IN THE FRONT...AND
MID LEVEL FLOW PARALLEL TO THE BOUNDARY...TRAINING OF STORMS IS
POSSIBLE. PWATS ALSO HIGH IN THE 1.9 TO 2 INCH RANGE...FURTHERING
HEAVY RAIN CHANCES. HOWEVER THIS AREA HAS BEEN DRIER AND FFG IS
HOVERING AROUND 3 INCHES OR JUST BELOW FOR 3 HOURS...THEREFORE THE
FLASH FLOOD THREAT IS MINIMIZED SOME.
AN UPPER LEVEL TROUGH WILL DIG INTO THE WESTERN US WITH A WEST TO
SOUTHWEST FLOW PATTERN SETTING UP TOWARD MID WEEK. A STRONGER AREA
OF LOW PRESSURE IS EXPECTED TO LIFT OUT OF THE SOUTHERN HIGH PLAINS
THROUGH IOWA AND INTO THE GREAT LAKES TUESDAY INTO WEDNESDAY. THIS
SYSTEM WILL EJECT ENERGY INTERACTING WITH THE LINGERING BOUNDARY
BRINGING THE NEXT WIDESPREAD CHANCES FOR PRECIPITATION TO MUCH OF
THE STATE. SHEAR PARAMETERS ALSO INCREASE WITH THE APPROACHING AREA
OF LOW PRESSURE ALLOWING FOR SEVERE WEATHER CHANCES AS WELL. WRAP-
AROUND PRECIP POSSIBLE INTO WEDNESDAY/WEDNESDAY NIGHT WITH HIGH
PRESSURE TO BUILD INTO THE AREA BY THURSDAY/FRIDAY. THIS SHOULD
ALLOW THE AREA TO DRY OUT BY THE END OF THE WEEK BEFORE PRECIP
CHANCES RETURN FOR THE WEEKEND WITH ANOTHER UPPER LEVEL TROUGH
PUSHING EAST FROM THE ROCKIES AND THROUGH THE NORTHERN PLAINS.
MODELS IN DISAGREEMENT OVER HOW FAR NORTH THIS SYSTEM WILL
TRACK...WITH THE EC MORE BULLISH KEEPING IT FURTHER SOUTH WHICH
WOULD BE MORE OF AN IMPACT TO THE CWA VERSUS THE GFS WHICH KEEPS THE
MAIN TROUGH ACROSS SOUTHERN CANADA.
TEMPERATURES EXPECTED TO BE HOT AND HUMID SUNDAY AS DEWPOINTS
INCREASE AHEAD OF THE COLD FRONT AND H85 TEMPS PUSH INTO THE LOW 20S
CELSIUS IN SOUTHERLY TO SOUTHWESTERLY FLOW. TEMPS TO DROP INTO THE
MID TEENS CELSIUS AS THE FRONT SAGS SOUTH...WITH COOLER TEMPS FOR
MUCH OF THE WEEK. TEMPS EXPECTED TO RETURN TO THE 80S AS SOUTHERLY
FLOW WARMS THINGS BACK UP AGAIN FRIDAY INTO SATURDAY AHEAD OF THE
UPPER LEVEL TROUGH.
&&
.AVIATION...17/00Z
ISSUED AT 714 PM CDT SUN AUG 16 2015
PRIMARY CONCERN THROUGH THE PERIOD WILL BE CONVECTIVE TRENDS AND
ASSOCIATED CATEGORY DEGRADATIONS...FOLLOWED BY POTENTIAL STRATUS
LATE IN THE PERIOD. HAVE PLAYED THUNDER AND CATEGORY RESTRICTIONS
SOMEWHAT CONSERVATIVE DEPENDING ON NEAR TERM TRENDS WITH A FAIRLY
WIDE VARIABILITY DEPENDING ON STORMS. WILL LEAVE BROADER VICINITY
WORDING UNTIL CONFIDENCE INCREASES ON THE ORDER OF HOURS WITH
PRECIP POTENTIAL RIGHT ON INTO MON. MODELS SUGGEST LOWERING CIGS
WITH SAGGING FRONT AND OUTFLOW BOUNDARIES...ALONG WITH PROLONGED
PERIOD OF SCATTERED PRECIP.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...BEERENDS
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1148 PM CDT FRI AUG 14 2015
.SYNOPSIS...
ISSUED AT 237 PM CDT FRI AUG 14 2015
THE WEAK SHORT WAVE TROUGH THAT PRODUCED A FEW SPRINKLES AND
LIGHT SHOWERS ACROSS THE AREA HAS MOVED SOUTHEAST OF THE CWA.
HIGH PRESSURE ALOFT IS BUILDING INTO THE MIDWEST WITH SURFACE
HIGH PRESSURE CENTERED JUST TO OUR SOUTH OVER MO SUPPORTING WEAK
WAA. AN AREA OF DEVELOPING CU IN NORTHEAST IOWA INDICATED BY
SATELLITE IS OF INTEREST AS A POTENTIAL IGNITION POINT FOR
STORMS...THOUGH LAPS SOUNDINGS INDICATE ENOUGH LOW-LEVEL DRY AIR
TO HAMPER THAT PROCESS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 237 PM CDT FRI AUG 14 2015
MAIN CONCERN IN THIS TIME FRAME IS THE LOWS CHANCE OF DIURNALLY-
DRIVEN SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING.
HRRR AND RAP SEEM A LITTLE AGGRESSIVE OR AT LEAST TOO FAST IN
DEVELOPING CONVECTION THIS AFTERNOON AS SATELLITE CURRENTLY
INDICATES NOT MUCH MORE THAN MODERATE CU. PLENTY OF CAPE IS
AVAILABLE ALTHOUGH SHEAR IS ON THE LOW SIDE FOR ORGANIZED/SEVERE
STORMS. AT THIS POINT PLAN ON FOCUSING LOW POPS IN THE
NORTHEASTERN PART OF THE CWA JUST THROUGH THE EVENING HOURS SINCE
DIURNAL FORCING IS THE MAIN DRIVER FOR ISOLATED COVERAGE.
VERY LIGHT WINDS AND DECREASING CLOUDS OVERNIGHT COULD LEAD TO
SOME PATCHY FOG TOWARD SUNRISE. THIS WILL BE SHORT-LIVED AS MORE
ABUNDANT SUNSHINE TOMORROW COMPARED TO TODAY WILL LEAD TO HIGHER
MAX TEMPS IN THE UPPER 80S TO NEAR 90. PRECIP CHANCES ARE NIL WITH
NEITHER A FOCUS NOR A TRIGGER AVAILABLE DESPITE A WARM AND HUMID
AIR MASS. WOLF
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 237 PM CDT FRI AUG 14 2015
FORECAST FOCUS ON HOT AND HUMID CONDITIONS ON SUNDAY THEN A MORE
ACTIVE PATTERN NEXT WEEK.
SUNDAY...HOT AND HUMID WITH PLENTY OF SUNSHINE WITH AN UPPER LEVEL
RIDGE OVER THE AREA. FORECAST SOUNDINGS INDICATE A CAP IN PLACE AND
850 MB TEMPERATURES WILL BE AT LEAST 20C. A COLD FRONT WILL EXTEND
FROM UPPER MI TO CENTRAL MN AND THEN TO FAR NW KS. WITH THE CAPPING
ATMOSPHERE AND NO TRIGGER FOR CONVECTION I WILL KEEP THE FORECAST
DRY. MANY LOCATIONS SHOULD SEE AFTERNOON TEMPERATURES SOAR TO AROUND
90 OR THE LOWER 90S...WITH HEAT INDEX VALUES AT LEAST IN THE MID 90S.
MONDAY THROUGH FRIDAY...A MORE ACTIVE PATTERN STILL IN THE OFFING
BUT LOW CONFIDENCE IN THE DETAILS...SUCH AS TIMING/INTENSITY OF
STORM SYSTEMS. DETERMINISTIC MODELS ARE VERY INCONSISTENT FROM RUN
TO RUN. OVERALL THE ECMWF IS WETTER THAN THE GFS. IN TERMS OF
SENSIBLE WEATHER IF THE ECMWF IS CORRECT THEN THERE WILL BE CHANCES
FOR THUNDERSTORMS THIS ENTIRE WEEK...AND THE CURRENT GRIDS SUPPORT
THIS IDEA. BASICALLY A ZONAL FLOW ALOFT WILL BE IN PLACE WITH AN
EAST-WEST SURFACE FRONTAL BOUNDARY MEANDERING OVER THE CWA. WAVES IN
THE FLOW WILL INTERACT WITH THE BOUNDARY...AND A WARM MOIST
AIR MASS...TO PRODUCE PERIODIC SHOWERS AND THUNDERSTORMS. ON THE
OTHER HAND...THE GFS INDICATES A RATHER DEEP UPPER LEVEL
TROUGH/INTENSIFYING CYCLONE IN THE MIDWEST BY MID WEEK...AND THEN
DRY AFTERWARDS. IT IS UNCLEAR AT THIS TIME WHICH MODEL HAS THE BEST
HANDLE ON THE UPSTREAM ENERGY. THEREFORE...IT IS TOO EARLY FOR
DETAILS CONCERNING SEVERE WEATHER AND HEAVY RAIN POTENTIAL DUE TO
THE LOW CONFIDENCE IN THE MODELS. MAXIMUM TEMPERATURES MUCH OF THE
WEEK WILL BE IN THE UPPER 70S TO MID 80S...WITH LOWS IN THE 60S.
HAASE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1141 PM CDT FRI AUG 14 2015
OUTSIDE OF SOME PATCHY 2-6SM FOG AROUND DAYBREAK EXPECT VFR CONDS
WITH LIGHT S/SW WINDS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...WOLF
SHORT TERM...WOLF
LONG TERM...HAASE
AVIATION...05
AREA FORECAST DISCUSSION
NWS GOODLAND KS
932 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 928 PM MDT SUN AUG 16 2015
UPDATED THE FORECAST FOR TONIGHT BASED ON LATEST RADAR TRENDS AND
MODEL DATA. CURRENT LINE OF STORMS SHOULD BE SOUTH OF THE AREA BY
MIDNIGHT OR SHORTLY AFTER. OVERNIGHT ANOTHER ROUND OF STORMS MAY
MOVE ACROSS THE NORTHERN PART OF THE AREA. HOWEVER AM SOMEWHAT
DOUBTFUL OF THIS SINCE THAT IS BEHIND THE COLD FRONT AND ANY
STORMS THAT HAVE TRIED TO MOVE OVER THE AREA BEHIND THE FRONT HAVE
NOT SURVIVED. LOWERED CHANCES OVERNIGHT SOME TO ACCOUNT FOR THIS
BUT STILL KEPT A MENTION OF RAIN GOING.
UPDATE ISSUED AT 847 PM MDT SUN AUG 16 2015
THE STORM ACTIVITY WHICH PROMPTED THE WATCH HAS MOVED OUT OF THE
WATCH AREA. IN ADDITION NO FURTHER HEAVY RAIN DEVELOPMENT IS
EXPECTED THROUGH THE REST OF THE NIGHT.
UPDATE ISSUED AT 700 PM MDT SUN AUG 16 2015
UPDATED FORECAST TO ACCOUNT FOR STORMS BEING TIED TO THE COLD
FRONT AS IT IS PUSHED SOUTHWARD. EXPECT THESE STORMS TO MOVE
SOUTH THROUGH THE REST OF THE AREA THIS EVENING...AND BE SOUTH OF
THE AREA AN HOUR OR SO AFTER MIDNIGHT.
BEHIND THE FRONT THE COOLER AIR AND LACK OF LIFT HAVE SERVED TO
END ANY STORMS THAT LINGER TOO LONG BEHIND THE FRONT. DO EXPECT
THE STORM ACTIVITY EAST OF HIGHWAY 25 TO CONTINUE INTO MID
EVENING BEFORE MOVING EAST OF THE AREA DUE TO THE NOSE OF THE LOW
LEVEL JET HELPING TO SUSTAIN THOSE STORMS.
TO THE WEST ANOTHER AREA OF STORMS IS SLOWLY MOVING TOWARD THE
AREA. HAVE NOTICED THE LEADING LINE OF STORMS HAS DISSIPATED AS
THEY ENCOUNTER THE FRONT. MODELS SHOW SOME ISENTROPIC OVER THE
WESTERN PORTIONS OF THE AREA...SO WILL HAVE HIGHER CHANCES FOR
RAIN THERE DECLINING TO THE EAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 16 2015
WV IMAGERY AND RAP ANALYSIS SHOWS RIDGE CENTERED OVER SOUTHERN
CALIFORNIA WITH AXIS EXTENDING ACROSS THE HIGH PLAINS AND INTO THE
GREAT LAKES REGION. PLUMES OF MID LEVEL MOISTURE ORIGINATING IN THE
PACIFIC ARE ROTATING AROUND THE EASTERN AND NORTHERN PERIPHERY OF THE
LARGE SCALE RIDGE INTO THE ROCKIES AND HIGH PLAINS. DIFFLUENT FLOW IS
CURRENTLY IN PLACE ACROSS THE CENTRAL ROCKIES WITH TROUGH DIGGING
INTO THE NORTHERN PLAINS. A FEW WEAKER SHORTWAVE TROUGHS ARE JUST TO
THE WEST/NORTHWEST OF OUR CWA. AT THE SURFACE QUASI-STATIONARY FRONT
CURRENTLY EXTENDS ACROSS CENTRAL NEBRASKA INTO NORTHCENTRAL COLORADO
OVER THE FAR NORTHWEST PART OF OUR CWA. PREFRONTAL TROUGH AXIS IS IN
PLACE FROM SOUTHEAST COLORADO OVER GOODLAND AND NORTON KANSAS.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY SHOULD INITIATE
WITHIN THE NEXT FEW HOURS ALONG FRONT AND SURFACE TROUGH WITH
COVERAGE INCREASING THIS EVENING AS A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATE ACROSS THE REGION. RECENT TRENDS IN ARW/NMM HAVE BEEN
TO SHIFT MOST ORGANIZED THUNDERSTORM CLUSTER TO THE SOUTH ROUGHLY
ALONG AND SOUTH OF INTERSTATE 70. CURRENTLY THE ORIENTATION OF FLOW
ALOFT AND OTHER GUIDANCE STILL SHOWING THUNDERSTORM CLUSTERS
ORIGINATING FROM THE WEST OR NORTHWEST OF THIS. EITHER WAY...DEEP
MOIST AIR MASS AND DECENT INSTABILITY AHEAD OF FRONT WILL SUPPORT
ACTIVITY ACROSS MUCH OF CWA TRANSITIONING EASTWARD. STRONGEST CAPE
AXIS IF FURTHER EAST THAN PREVIOUS GUIDANCE INDICATED...THOUGH THERE
IS ENOUGH ELEVATED CAPE TO AT LEAST CONSIDER POTENTIAL FOR
MARGINALLY SEVERE HAIL. DCAPE 1000-1500 J/KG COINCIDING DRY ADIABATIC
PROFILES BELOW 700MB COULD SUPPORT ISOLATED SEVERE DOWNDRAFT
POTENTIAL DURING THE AFTERNOON...THOUGH AS MIXING RATIOS INCREASE
BELOW 700MB THIS EVENING THIS THREAT WILL LIKELY DIMINISH.
REGARDING FLASH FLOOD WATCH...ANOMALOUSLY HIGH PWAT VALUES 1.2-1.6
WILL ONLY INCREASE THROUGH THE NIGHT APPROACHING 1.7-1.8 WHICH IS
WELL WITHIN 99TH PERCENTILE OR 3 STANDARD DEVIATIONS FROM NORMAL.
WITH VERY SLOW STORM MOTIONS AND POSSIBILITY FOR
TRAINING/BACKBUILDING I AM COMFORTABLE WITH FLASH FLOOD WATCH. IF
ARW/NMM SOLUTION PANS OUT THEN WE MAY NEED TO CONSIDER ADDING
SOUTHERN PART OF FORECAST AREA TO WATCH.
MONDAY...WHILE FRONTAL PASSAGE SHOULD OCCUR FROM NORTH TO SOUTH
MONDAY...GUIDANCE IS SHOWING A LOT OF SPREAD ON TIMING. THIS LOWERS
CONFIDENCE/TIMING OF ADDITIONAL THUNDERSTORM ACTIVITY. ARW/NMM SHOW
A MORE ORGANIZED THUNDERSTORM CLUSTER DEVELOPING ALONG FRONT MONDAY
MORNING...THOUGH OTHER GUIDANCE IS SHOWING PREDOMINANTLY ISOLATED TO
SCATTERED ACTIVITY LINGERING ACROSS THE AREA. DEEP MOIST LAYER
REMAINS IN PLACE...SO WITH POTENTIAL FOR OVERRUNNING ALONG BAROCLINIC
ZONE...IT IS POSSIBLE FOR A MORE ORGANIZED CLUSTER IF WE CONTINUE TO
SEE WEAK HEIGHT FALL...WHICH COULD ALSO RESULT CONTINUING THREAT FOR
FLASH FLOODING. SEVERE THUNDERSTORM THREAT WILL BE HIGHLY DEPENDENT
ON FRONTAL POSITION/TIMING AS BETTER INSTABILITY WILL TEND TO BE
AHEAD OF FRONT. AS WITH TODAY...THREATS WOULD BE LARGE HAIL/DAMAGING
WINDS ALONG/SOUTH OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 252 PM MDT SUN AUG 16 2015
FOR THIS EXTENDED FORECAST PACKAGE...A STRONG COLD FRONT IS EXPECTED
TO MOVE THROUGH ON TUESDAY...BRINGING AN END TO SIGNIFICANT
PRECIPITATION CHANCES AND A TEMPORARY PARDON FROM THE WARMTH AND
HUMIDITY. ZONAL FLOW ALOFT RETURNS BEHIND TUESDAY`S SYSTEM. WITH
SOUTHERLY LOW LEVEL FLOW...A WARMING TREND IS EXPECTED TO BEGIN
THURSDAY. HOWEVER...YET ANOTHER UPPER LEVEL DISTURBANCE IS EXPECTED
TO FORCE A COLD FRONT THROUGH THIS WEEKEND...BRINING ANOTHER CHANCE
FOR BELOW NORMAL TEMPERATURES.
THE MOST IMPACTFUL WEATHER IN THE EXTENDED FORECAST PERIOD IS
ANTICIPATED MONDAY EVENING THROUGH TUESDAY EVENING. ACTIVE WEATHER
IS FORECAST AS A LARGE NEGATIVELY TILTED TROUGH KICKS OUT OVER THE
HIGH PLAINS. STRONG/SEVERE THUNDERSTORMS MAY BE ONGOING ACROSS
PORTIONS OF THE REGION MONDAY EVENING DEPENDING ON THE FRONT
LOCATION AND ENVIRONMENTAL PARAMETERS. ANY POTENTIAL SEVERE WEATHER
THREAT MAY BE HIGHER MONDAY EVENING AS INITIAL DEVELOPMENT IN
COLORADO SHOULD BE MOVING IN. THE PRIMARY THREATS FOR SEVERE WEATHER
WILL BE LARGE HAIL AND DAMAGING WINDS. AS MENTIONED IN THE DAY 2
STORM PREDICTION CENTER OUTLOOK...SURFACE VORTICITY/HELICITY
MAXIMIZED IN THE VICINITY OF THE FRONT MAY PROVIDE AN OPPORTUNITY
FOR A TORNADO TO OCCUR. CONFIDENCE IN THIS ISN`T AS HIGH AS HIGHER
RESOLUTION GUIDANCE INDICATES THE POTENTIAL FOR COLD POOL
DEVELOPMENT...HIGHLIGHTING A HIGHER THREAT OF MCS DEVELOPMENT WITH
DAMAGING WINDS AS THE MAIN THREAT. IN TERMS OF FLASH FLOODING...A
THREAT WILL STILL EXIST ESPECIALLY IF HEAVY RAINS ARE RECEIVED
TONIGHT. PRECIPITABLE WATER VALUES FALL AS THE FRONT DOES FORCE SOME
MOISTURE SOUTH SO WE NO LONGER EXPECT PRECIPITABLE WATER VALUES
NEARING THE 99TH PERCENTILE. STORM MOVEMENT REMAINS QUITE SLOW IN
TERMS OF STEERING WINDS ALOFT SO COLD POOL FORMATION/MOVEMENT SHOULD
BE THE PRIMARY DRIVER. THEREFORE...A FLASH FLOOD THREAT MAY PERSIST
AND ANOTHER FLASH FLOOD WATCH MAY BE NEEDED FOR MONDAY EVENING IN
LATER FORECAST PACKAGES.
ON TUESDAY...THE FRONT SHOULD FINALLY SLIDE ALL THE WAY THROUGH THE
REGION...RESTRICTING HIGHEST INSTABILITY SOUTH OF THE FRONT AND
PRIMARILY SOUTH OF THE REGION. HOWEVER...CONFIDENCE IS LOW ON WHEN
THIS COLD FRONT WILL SURGE SOUTH AND THERE MAY BE ENOUGH TIME FOR
STORM DEVELOPMENT AHEAD OF THE FRONT. THIS WOULD MEAN SEVERE WEATHER
IS POSSIBLE BUT UNLIKELY TUESDAY. HOWEVER...ADDITIONAL PERTURBATIONS
MOVE IN FROM THE NORTHWEST BEHIND THE MAIN FORCING AND WITH SOME
INSTABILITY REMAINING IN THE POST-FRONTAL ENVIRONMENT...THERE SHOULD
BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TUESDAY AFTERNOON BUT
COVERAGE AND INTENSITY REMAINS IN DOUBT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 536 PM MDT SUN AUG 16 2015
VFR TO IFR CONDITIONS FORECAST FOR THE 0Z TAFS. MAIN ISSUE IS
TIMING THE BEST WINDOW FOR STORMS TO MOVE OVER THE TAF SITES.
STORMS HAVE BEEN DEVELOPING VERY SPORADICALLY ALONG AND BEHIND A
COLD FRONT THAT IS SLOWLY MOVING SOUTH THROUGH THE AREA. LOOKS
LIKE THE BEST WINDOW OF OPPORTUNITY FOR STORMS OVER THE SITES WILL
BE THE EVENING HOURS. AFTER THAT CONFIDENCE IS LESS WHETHER STORMS
WILL BE OVER THE SITES SO HAVE VCTS UNTIL LATER IN THE NIGHT WHEN
ENVIRONMENT LOOKS LESS FAVORABLE FOR STORM COVERAGE.
MAIN THREAT WITH THESE STORMS WILL BE REDUCTION IN VISIBILITIES
DUE TO THE HEAVY RAINFALL. THOUGHT ABOUT PLACING A MENTION OF MVFR
VISIBILITY IN THE TEMPO GROUPS FOR THIS REASON...BUT AM NOT THAT
CONFIDENT THE REDUCED VISIBILITY FROM THE STORMS WILL BE LONG
ENOUGH TO WARRANT THAT LOW A MENTION IN THE TAFS. KMCK DID REPORT
VISIBILITIES AROUND 2 MILES DUE TO HEAVY RAINFALL FOR A FEW
MINUTES...SO WOULD EXPECT THESE BRIEF REDUCTIONS IN VISIBILITIES
IF HEAVY RAINFALL MOVES OVER THE SITES.
OVERNIGHT LOW CLOUDS WILL MOVE INTO THE AREA FROM THE NORTH
BRINGING MVFR TO POSSIBLY IFR CONDITIONS TO KMCK...BUT LOOKS TO REMAIN
NORTH OF KGLD AT THIS TIME. CEILINGS WILL REMAIN MVFR THROUGH
MOST OF THE MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
848 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 847 PM MDT SUN AUG 16 2015
THE STORM ACTIVITY WHICH PROMPTED THE WATCH HAS MOVED OUT OF THE
WATCH AREA. IN ADDITION NO FURTHER HEAVY RAIN DEVELOPMENT IS
EXPECTED THROUGH THE REST OF THE NIGHT.
UPDATE ISSUED AT 700 PM MDT SUN AUG 16 2015
UPDATED FORECAST TO ACCOUNT FOR STORMS BEING TIED TO THE COLD
FRONT AS IT IS PUSHED SOUTHWARD. EXPECT THESE STORMS TO MOVE
SOUTH THROUGH THE REST OF THE AREA THIS EVENING...AND BE SOUTH OF
THE AREA AN HOUR OR SO AFTER MIDNIGHT.
BEHIND THE FRONT THE COOLER AIR AND LACK OF LIFT HAVE SERVED TO
END ANY STORMS THAT LINGER TOO LONG BEHIND THE FRONT. DO EXPECT
THE STORM ACTIVITY EAST OF HIGHWAY 25 TO CONTINUE INTO MID
EVENING BEFORE MOVING EAST OF THE AREA DUE TO THE NOSE OF THE LOW
LEVEL JET HELPING TO SUSTAIN THOSE STORMS.
TO THE WEST ANOTHER AREA OF STORMS IS SLOWLY MOVING TOWARD THE
AREA. HAVE NOTICED THE LEADING LINE OF STORMS HAS DISSIPATED AS
THEY ENCOUNTER THE FRONT. MODELS SHOW SOME ISENTROPIC OVER THE
WESTERN PORTIONS OF THE AREA...SO WILL HAVE HIGHER CHANCES FOR
RAIN THERE DECLINING TO THE EAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 16 2015
WV IMAGERY AND RAP ANALYSIS SHOWS RIDGE CENTERED OVER SOUTHERN
CALIFORNIA WITH AXIS EXTENDING ACROSS THE HIGH PLAINS AND INTO THE
GREAT LAKES REGION. PLUMES OF MID LEVEL MOISTURE ORIGINATING IN THE
PACIFIC ARE ROTATING AROUND THE EASTERN AND NORTHERN PERIPHERY OF THE
LARGE SCALE RIDGE INTO THE ROCKIES AND HIGH PLAINS. DIFFLUENT FLOW IS
CURRENTLY IN PLACE ACROSS THE CENTRAL ROCKIES WITH TROUGH DIGGING
INTO THE NORTHERN PLAINS. A FEW WEAKER SHORTWAVE TROUGHS ARE JUST TO
THE WEST/NORTHWEST OF OUR CWA. AT THE SURFACE QUASI-STATIONARY FRONT
CURRENTLY EXTENDS ACROSS CENTRAL NEBRASKA INTO NORTHCENTRAL COLORADO
OVER THE FAR NORTHWEST PART OF OUR CWA. PREFRONTAL TROUGH AXIS IS IN
PLACE FROM SOUTHEAST COLORADO OVER GOODLAND AND NORTON KANSAS.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY SHOULD INITIATE
WITHIN THE NEXT FEW HOURS ALONG FRONT AND SURFACE TROUGH WITH
COVERAGE INCREASING THIS EVENING AS A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATE ACROSS THE REGION. RECENT TRENDS IN ARW/NMM HAVE BEEN
TO SHIFT MOST ORGANIZED THUNDERSTORM CLUSTER TO THE SOUTH ROUGHLY
ALONG AND SOUTH OF INTERSTATE 70. CURRENTLY THE ORIENTATION OF FLOW
ALOFT AND OTHER GUIDANCE STILL SHOWING THUNDERSTORM CLUSTERS
ORIGINATING FROM THE WEST OR NORTHWEST OF THIS. EITHER WAY...DEEP
MOIST AIR MASS AND DECENT INSTABILITY AHEAD OF FRONT WILL SUPPORT
ACTIVITY ACROSS MUCH OF CWA TRANSITIONING EASTWARD. STRONGEST CAPE
AXIS IF FURTHER EAST THAN PREVIOUS GUIDANCE INDICATED...THOUGH THERE
IS ENOUGH ELEVATED CAPE TO AT LEAST CONSIDER POTENTIAL FOR
MARGINALLY SEVERE HAIL. DCAPE 1000-1500 J/KG COINCIDING DRY ADIABATIC
PROFILES BELOW 700MB COULD SUPPORT ISOLATED SEVERE DOWNDRAFT
POTENTIAL DURING THE AFTERNOON...THOUGH AS MIXING RATIOS INCREASE
BELOW 700MB THIS EVENING THIS THREAT WILL LIKELY DIMINISH.
REGARDING FLASH FLOOD WATCH...ANOMALOUSLY HIGH PWAT VALUES 1.2-1.6
WILL ONLY INCREASE THROUGH THE NIGHT APPROACHING 1.7-1.8 WHICH IS
WELL WITHIN 99TH PERCENTILE OR 3 STANDARD DEVIATIONS FROM NORMAL.
WITH VERY SLOW STORM MOTIONS AND POSSIBILITY FOR
TRAINING/BACKBUILDING I AM COMFORTABLE WITH FLASH FLOOD WATCH. IF
ARW/NMM SOLUTION PANS OUT THEN WE MAY NEED TO CONSIDER ADDING
SOUTHERN PART OF FORECAST AREA TO WATCH.
MONDAY...WHILE FRONTAL PASSAGE SHOULD OCCUR FROM NORTH TO SOUTH
MONDAY...GUIDANCE IS SHOWING A LOT OF SPREAD ON TIMING. THIS LOWERS
CONFIDENCE/TIMING OF ADDITIONAL THUNDERSTORM ACTIVITY. ARW/NMM SHOW
A MORE ORGANIZED THUNDERSTORM CLUSTER DEVELOPING ALONG FRONT MONDAY
MORNING...THOUGH OTHER GUIDANCE IS SHOWING PREDOMINANTLY ISOLATED TO
SCATTERED ACTIVITY LINGERING ACROSS THE AREA. DEEP MOIST LAYER
REMAINS IN PLACE...SO WITH POTENTIAL FOR OVERRUNNING ALONG BAROCLINIC
ZONE...IT IS POSSIBLE FOR A MORE ORGANIZED CLUSTER IF WE CONTINUE TO
SEE WEAK HEIGHT FALL...WHICH COULD ALSO RESULT CONTINUING THREAT FOR
FLASH FLOODING. SEVERE THUNDERSTORM THREAT WILL BE HIGHLY DEPENDENT
ON FRONTAL POSITION/TIMING AS BETTER INSTABILITY WILL TEND TO BE
AHEAD OF FRONT. AS WITH TODAY...THREATS WOULD BE LARGE HAIL/DAMAGING
WINDS ALONG/SOUTH OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 252 PM MDT SUN AUG 16 2015
FOR THIS EXTENDED FORECAST PACKAGE...A STRONG COLD FRONT IS EXPECTED
TO MOVE THROUGH ON TUESDAY...BRINGING AN END TO SIGNIFICANT
PRECIPITATION CHANCES AND A TEMPORARY PARDON FROM THE WARMTH AND
HUMIDITY. ZONAL FLOW ALOFT RETURNS BEHIND TUESDAY`S SYSTEM. WITH
SOUTHERLY LOW LEVEL FLOW...A WARMING TREND IS EXPECTED TO BEGIN
THURSDAY. HOWEVER...YET ANOTHER UPPER LEVEL DISTURBANCE IS EXPECTED
TO FORCE A COLD FRONT THROUGH THIS WEEKEND...BRINING ANOTHER CHANCE
FOR BELOW NORMAL TEMPERATURES.
THE MOST IMPACTFUL WEATHER IN THE EXTENDED FORECAST PERIOD IS
ANTICIPATED MONDAY EVENING THROUGH TUESDAY EVENING. ACTIVE WEATHER
IS FORECAST AS A LARGE NEGATIVELY TILTED TROUGH KICKS OUT OVER THE
HIGH PLAINS. STRONG/SEVERE THUNDERSTORMS MAY BE ONGOING ACROSS
PORTIONS OF THE REGION MONDAY EVENING DEPENDING ON THE FRONT
LOCATION AND ENVIRONMENTAL PARAMETERS. ANY POTENTIAL SEVERE WEATHER
THREAT MAY BE HIGHER MONDAY EVENING AS INITIAL DEVELOPMENT IN
COLORADO SHOULD BE MOVING IN. THE PRIMARY THREATS FOR SEVERE WEATHER
WILL BE LARGE HAIL AND DAMAGING WINDS. AS MENTIONED IN THE DAY 2
STORM PREDICTION CENTER OUTLOOK...SURFACE VORTICITY/HELICITY
MAXIMIZED IN THE VICINITY OF THE FRONT MAY PROVIDE AN OPPORTUNITY
FOR A TORNADO TO OCCUR. CONFIDENCE IN THIS ISN`T AS HIGH AS HIGHER
RESOLUTION GUIDANCE INDICATES THE POTENTIAL FOR COLD POOL
DEVELOPMENT...HIGHLIGHTING A HIGHER THREAT OF MCS DEVELOPMENT WITH
DAMAGING WINDS AS THE MAIN THREAT. IN TERMS OF FLASH FLOODING...A
THREAT WILL STILL EXIST ESPECIALLY IF HEAVY RAINS ARE RECEIVED
TONIGHT. PRECIPITABLE WATER VALUES FALL AS THE FRONT DOES FORCE SOME
MOISTURE SOUTH SO WE NO LONGER EXPECT PRECIPITABLE WATER VALUES
NEARING THE 99TH PERCENTILE. STORM MOVEMENT REMAINS QUITE SLOW IN
TERMS OF STEERING WINDS ALOFT SO COLD POOL FORMATION/MOVEMENT SHOULD
BE THE PRIMARY DRIVER. THEREFORE...A FLASH FLOOD THREAT MAY PERSIST
AND ANOTHER FLASH FLOOD WATCH MAY BE NEEDED FOR MONDAY EVENING IN
LATER FORECAST PACKAGES.
ON TUESDAY...THE FRONT SHOULD FINALLY SLIDE ALL THE WAY THROUGH THE
REGION...RESTRICTING HIGHEST INSTABILITY SOUTH OF THE FRONT AND
PRIMARILY SOUTH OF THE REGION. HOWEVER...CONFIDENCE IS LOW ON WHEN
THIS COLD FRONT WILL SURGE SOUTH AND THERE MAY BE ENOUGH TIME FOR
STORM DEVELOPMENT AHEAD OF THE FRONT. THIS WOULD MEAN SEVERE WEATHER
IS POSSIBLE BUT UNLIKELY TUESDAY. HOWEVER...ADDITIONAL PERTURBATIONS
MOVE IN FROM THE NORTHWEST BEHIND THE MAIN FORCING AND WITH SOME
INSTABILITY REMAINING IN THE POST-FRONTAL ENVIRONMENT...THERE SHOULD
BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TUESDAY AFTERNOON BUT
COVERAGE AND INTENSITY REMAINS IN DOUBT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 536 PM MDT SUN AUG 16 2015
VFR TO IFR CONDITIONS FORECAST FOR THE 0Z TAFS. MAIN ISSUE IS
TIMING THE BEST WINDOW FOR STORMS TO MOVE OVER THE TAF SITES.
STORMS HAVE BEEN DEVELOPING VERY SPORADICALLY ALONG AND BEHIND A
COLD FRONT THAT IS SLOWLY MOVING SOUTH THROUGH THE AREA. LOOKS
LIKE THE BEST WINDOW OF OPPORTUNITY FOR STORMS OVER THE SITES WILL
BE THE EVENING HOURS. AFTER THAT CONFIDENCE IS LESS WHETHER STORMS
WILL BE OVER THE SITES SO HAVE VCTS UNTIL LATER IN THE NIGHT WHEN
ENVIRONMENT LOOKS LESS FAVORABLE FOR STORM COVERAGE.
MAIN THREAT WITH THESE STORMS WILL BE REDUCTION IN VISIBILITIES
DUE TO THE HEAVY RAINFALL. THOUGHT ABOUT PLACING A MENTION OF MVFR
VISIBILITY IN THE TEMPO GROUPS FOR THIS REASON...BUT AM NOT THAT
CONFIDENT THE REDUCED VISIBILITY FROM THE STORMS WILL BE LONG
ENOUGH TO WARRANT THAT LOW A MENTION IN THE TAFS. KMCK DID REPORT
VISIBILITIES AROUND 2 MILES DUE TO HEAVY RAINFALL FOR A FEW
MINUTES...SO WOULD EXPECT THESE BRIEF REDUCTIONS IN VISIBILITIES
IF HEAVY RAINFALL MOVES OVER THE SITES.
OVERNIGHT LOW CLOUDS WILL MOVE INTO THE AREA FROM THE NORTH
BRINGING MVFR TO POSSIBLY IFR CONDITIONS TO KMCK...BUT LOOKS TO REMAIN
NORTH OF KGLD AT THIS TIME. CEILINGS WILL REMAIN MVFR THROUGH
MOST OF THE MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
708 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 700 PM MDT SUN AUG 16 2015
UPDATED FORECAST TO ACCOUNT FOR STORMS BEING TIED TO THE COLD
FRONT AS IT IS PUSHED SOUTHWARD. EXPECT THESE STORMS TO MOVE
SOUTH THROUGH THE REST OF THE AREA THIS EVENING...AND BE SOUTH OF
THE AREA AN HOUR OR SO AFTER MIDNIGHT.
BEHIND THE FRONT THE COOLER AIR AND LACK OF LIFT HAVE SERVED TO
END ANY STORMS THAT LINGER TOO LONG BEHIND THE FRONT. DO EXPECT
THE STORM ACTIVITY EAST OF HIGHWAY 25 TO CONTINUE INTO MID
EVENING BEFORE MOVING EAST OF THE AREA DUE TO THE NOSE OF THE LOW
LEVEL JET HELPING TO SUSTAIN THOSE STORMS.
TO THE WEST ANOTHER AREA OF STORMS IS SLOWLY MOVING TOWARD THE
AREA. HAVE NOTICED THE LEADING LINE OF STORMS HAS DISSIPATED AS
THEY ENCOUNTER THE FRONT. MODELS SHOW SOME ISENTROPIC OVER THE
WESTERN PORTIONS OF THE AREA...SO WILL HAVE HIGHER CHANCES FOR
RAIN THERE DECLINING TO THE EAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 16 2015
WV IMAGERY AND RAP ANALYSIS SHOWS RIDGE CENTERED OVER SOUTHERN
CALIFORNIA WITH AXIS EXTENDING ACROSS THE HIGH PLAINS AND INTO THE
GREAT LAKES REGION. PLUMES OF MID LEVEL MOISTURE ORIGINATING IN THE
PACIFIC ARE ROTATING AROUND THE EASTERN AND NORTHERN PERIPHERY OF THE
LARGE SCALE RIDGE INTO THE ROCKIES AND HIGH PLAINS. DIFFLUENT FLOW IS
CURRENTLY IN PLACE ACROSS THE CENTRAL ROCKIES WITH TROUGH DIGGING
INTO THE NORTHERN PLAINS. A FEW WEAKER SHORTWAVE TROUGHS ARE JUST TO
THE WEST/NORTHWEST OF OUR CWA. AT THE SURFACE QUASI-STATIONARY FRONT
CURRENTLY EXTENDS ACROSS CENTRAL NEBRASKA INTO NORTHCENTRAL COLORADO
OVER THE FAR NORTHWEST PART OF OUR CWA. PREFRONTAL TROUGH AXIS IS IN
PLACE FROM SOUTHEAST COLORADO OVER GOODLAND AND NORTON KANSAS.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY SHOULD INITIATE
WITHIN THE NEXT FEW HOURS ALONG FRONT AND SURFACE TROUGH WITH
COVERAGE INCREASING THIS EVENING AS A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATE ACROSS THE REGION. RECENT TRENDS IN ARW/NMM HAVE BEEN
TO SHIFT MOST ORGANIZED THUNDERSTORM CLUSTER TO THE SOUTH ROUGHLY
ALONG AND SOUTH OF INTERSTATE 70. CURRENTLY THE ORIENTATION OF FLOW
ALOFT AND OTHER GUIDANCE STILL SHOWING THUNDERSTORM CLUSTERS
ORIGINATING FROM THE WEST OR NORTHWEST OF THIS. EITHER WAY...DEEP
MOIST AIR MASS AND DECENT INSTABILITY AHEAD OF FRONT WILL SUPPORT
ACTIVITY ACROSS MUCH OF CWA TRANSITIONING EASTWARD. STRONGEST CAPE
AXIS IF FURTHER EAST THAN PREVIOUS GUIDANCE INDICATED...THOUGH THERE
IS ENOUGH ELEVATED CAPE TO AT LEAST CONSIDER POTENTIAL FOR
MARGINALLY SEVERE HAIL. DCAPE 1000-1500 J/KG COINCIDING DRY ADIABATIC
PROFILES BELOW 700MB COULD SUPPORT ISOLATED SEVERE DOWNDRAFT
POTENTIAL DURING THE AFTERNOON...THOUGH AS MIXING RATIOS INCREASE
BELOW 700MB THIS EVENING THIS THREAT WILL LIKELY DIMINISH.
REGARDING FLASH FLOOD WATCH...ANOMALOUSLY HIGH PWAT VALUES 1.2-1.6
WILL ONLY INCREASE THROUGH THE NIGHT APPROACHING 1.7-1.8 WHICH IS
WELL WITHIN 99TH PERCENTILE OR 3 STANDARD DEVIATIONS FROM NORMAL.
WITH VERY SLOW STORM MOTIONS AND POSSIBILITY FOR
TRAINING/BACKBUILDING I AM COMFORTABLE WITH FLASH FLOOD WATCH. IF
ARW/NMM SOLUTION PANS OUT THEN WE MAY NEED TO CONSIDER ADDING
SOUTHERN PART OF FORECAST AREA TO WATCH.
MONDAY...WHILE FRONTAL PASSAGE SHOULD OCCUR FROM NORTH TO SOUTH
MONDAY...GUIDANCE IS SHOWING A LOT OF SPREAD ON TIMING. THIS LOWERS
CONFIDENCE/TIMING OF ADDITIONAL THUNDERSTORM ACTIVITY. ARW/NMM SHOW
A MORE ORGANIZED THUNDERSTORM CLUSTER DEVELOPING ALONG FRONT MONDAY
MORNING...THOUGH OTHER GUIDANCE IS SHOWING PREDOMINANTLY ISOLATED TO
SCATTERED ACTIVITY LINGERING ACROSS THE AREA. DEEP MOIST LAYER
REMAINS IN PLACE...SO WITH POTENTIAL FOR OVERRUNNING ALONG BAROCLINIC
ZONE...IT IS POSSIBLE FOR A MORE ORGANIZED CLUSTER IF WE CONTINUE TO
SEE WEAK HEIGHT FALL...WHICH COULD ALSO RESULT CONTINUING THREAT FOR
FLASH FLOODING. SEVERE THUNDERSTORM THREAT WILL BE HIGHLY DEPENDENT
ON FRONTAL POSITION/TIMING AS BETTER INSTABILITY WILL TEND TO BE
AHEAD OF FRONT. AS WITH TODAY...THREATS WOULD BE LARGE HAIL/DAMAGING
WINDS ALONG/SOUTH OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 252 PM MDT SUN AUG 16 2015
FOR THIS EXTENDED FORECAST PACKAGE...A STRONG COLD FRONT IS EXPECTED
TO MOVE THROUGH ON TUESDAY...BRINGING AN END TO SIGNIFICANT
PRECIPITATION CHANCES AND A TEMPORARY PARDON FROM THE WARMTH AND
HUMIDITY. ZONAL FLOW ALOFT RETURNS BEHIND TUESDAY`S SYSTEM. WITH
SOUTHERLY LOW LEVEL FLOW...A WARMING TREND IS EXPECTED TO BEGIN
THURSDAY. HOWEVER...YET ANOTHER UPPER LEVEL DISTURBANCE IS EXPECTED
TO FORCE A COLD FRONT THROUGH THIS WEEKEND...BRINING ANOTHER CHANCE
FOR BELOW NORMAL TEMPERATURES.
THE MOST IMPACTFUL WEATHER IN THE EXTENDED FORECAST PERIOD IS
ANTICIPATED MONDAY EVENING THROUGH TUESDAY EVENING. ACTIVE WEATHER
IS FORECAST AS A LARGE NEGATIVELY TILTED TROUGH KICKS OUT OVER THE
HIGH PLAINS. STRONG/SEVERE THUNDERSTORMS MAY BE ONGOING ACROSS
PORTIONS OF THE REGION MONDAY EVENING DEPENDING ON THE FRONT
LOCATION AND ENVIRONMENTAL PARAMETERS. ANY POTENTIAL SEVERE WEATHER
THREAT MAY BE HIGHER MONDAY EVENING AS INITIAL DEVELOPMENT IN
COLORADO SHOULD BE MOVING IN. THE PRIMARY THREATS FOR SEVERE WEATHER
WILL BE LARGE HAIL AND DAMAGING WINDS. AS MENTIONED IN THE DAY 2
STORM PREDICTION CENTER OUTLOOK...SURFACE VORTICITY/HELICITY
MAXIMIZED IN THE VICINITY OF THE FRONT MAY PROVIDE AN OPPORTUNITY
FOR A TORNADO TO OCCUR. CONFIDENCE IN THIS ISN`T AS HIGH AS HIGHER
RESOLUTION GUIDANCE INDICATES THE POTENTIAL FOR COLD POOL
DEVELOPMENT...HIGHLIGHTING A HIGHER THREAT OF MCS DEVELOPMENT WITH
DAMAGING WINDS AS THE MAIN THREAT. IN TERMS OF FLASH FLOODING...A
THREAT WILL STILL EXIST ESPECIALLY IF HEAVY RAINS ARE RECEIVED
TONIGHT. PRECIPITABLE WATER VALUES FALL AS THE FRONT DOES FORCE SOME
MOISTURE SOUTH SO WE NO LONGER EXPECT PRECIPITABLE WATER VALUES
NEARING THE 99TH PERCENTILE. STORM MOVEMENT REMAINS QUITE SLOW IN
TERMS OF STEERING WINDS ALOFT SO COLD POOL FORMATION/MOVEMENT SHOULD
BE THE PRIMARY DRIVER. THEREFORE...A FLASH FLOOD THREAT MAY PERSIST
AND ANOTHER FLASH FLOOD WATCH MAY BE NEEDED FOR MONDAY EVENING IN
LATER FORECAST PACKAGES.
ON TUESDAY...THE FRONT SHOULD FINALLY SLIDE ALL THE WAY THROUGH THE
REGION...RESTRICTING HIGHEST INSTABILITY SOUTH OF THE FRONT AND
PRIMARILY SOUTH OF THE REGION. HOWEVER...CONFIDENCE IS LOW ON WHEN
THIS COLD FRONT WILL SURGE SOUTH AND THERE MAY BE ENOUGH TIME FOR
STORM DEVELOPMENT AHEAD OF THE FRONT. THIS WOULD MEAN SEVERE WEATHER
IS POSSIBLE BUT UNLIKELY TUESDAY. HOWEVER...ADDITIONAL PERTURBATIONS
MOVE IN FROM THE NORTHWEST BEHIND THE MAIN FORCING AND WITH SOME
INSTABILITY REMAINING IN THE POST-FRONTAL ENVIRONMENT...THERE SHOULD
BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TUESDAY AFTERNOON BUT
COVERAGE AND INTENSITY REMAINS IN DOUBT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 536 PM MDT SUN AUG 16 2015
VFR TO IFR CONDITIONS FORECAST FOR THE 0Z TAFS. MAIN ISSUE IS
TIMING THE BEST WINDOW FOR STORMS TO MOVE OVER THE TAF SITES.
STORMS HAVE BEEN DEVELOPING VERY SPORADICALLY ALONG AND BEHIND A
COLD FRONT THAT IS SLOWLY MOVING SOUTH THROUGH THE AREA. LOOKS
LIKE THE BEST WINDOW OF OPPORTUNITY FOR STORMS OVER THE SITES WILL
BE THE EVENING HOURS. AFTER THAT CONFIDENCE IS LESS WHETHER STORMS
WILL BE OVER THE SITES SO HAVE VCTS UNTIL LATER IN THE NIGHT WHEN
ENVIRONMENT LOOKS LESS FAVORABLE FOR STORM COVERAGE.
MAIN THREAT WITH THESE STORMS WILL BE REDUCTION IN VISIBILITIES
DUE TO THE HEAVY RAINFALL. THOUGHT ABOUT PLACING A MENTION OF MVFR
VISIBILITY IN THE TEMPO GROUPS FOR THIS REASON...BUT AM NOT THAT
CONFIDENT THE REDUCED VISIBILITY FROM THE STORMS WILL BE LONG
ENOUGH TO WARRANT THAT LOW A MENTION IN THE TAFS. KMCK DID REPORT
VISIBILITIES AROUND 2 MILES DUE TO HEAVY RAINFALL FOR A FEW
MINUTES...SO WOULD EXPECT THESE BRIEF REDUCTIONS IN VISIBILITIES
IF HEAVY RAINFALL MOVES OVER THE SITES.
OVERNIGHT LOW CLOUDS WILL MOVE INTO THE AREA FROM THE NORTH
BRINGING MVFR TO POSSIBLY IFR CONDITIONS TO KMCK...BUT LOOKS TO REMAIN
NORTH OF KGLD AT THIS TIME. CEILINGS WILL REMAIN MVFR THROUGH
MOST OF THE MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH UNTIL 6 AM MDT /7 AM CDT/ MONDAY FOR
KSZ001>003-013-014.
CO...FLASH FLOOD WATCH UNTIL 6 AM MDT MONDAY FOR COZ090-091.
NE...FLASH FLOOD WATCH UNTIL 6 AM MDT /7 AM CDT/ MONDAY FOR
NEZ079>081.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
556 PM MDT SUN AUG 16 2015
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 16 2015
WV IMAGERY AND RAP ANALYSIS SHOWS RIDGE CENTERED OVER SOUTHERN
CALIFORNIA WITH AXIS EXTENDING ACROSS THE HIGH PLAINS AND INTO THE
GREAT LAKES REGION. PLUMES OF MID LEVEL MOISTURE ORIGINATING IN THE
PACIFIC ARE ROTATING AROUND THE EASTERN AND NORTHERN PERIPHERY OF THE
LARGE SCALE RIDGE INTO THE ROCKIES AND HIGH PLAINS. DIFFLUENT FLOW IS
CURRENTLY IN PLACE ACROSS THE CENTRAL ROCKIES WITH TROUGH DIGGING
INTO THE NORTHERN PLAINS. A FEW WEAKER SHORTWAVE TROUGHS ARE JUST TO
THE WEST/NORTHWEST OF OUR CWA. AT THE SURFACE QUASI-STATIONARY FRONT
CURRENTLY EXTENDS ACROSS CENTRAL NEBRASKA INTO NORTHCENTRAL COLORADO
OVER THE FAR NORTHWEST PART OF OUR CWA. PREFRONTAL TROUGH AXIS IS IN
PLACE FROM SOUTHEAST COLORADO OVER GOODLAND AND NORTON KANSAS.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY SHOULD INITIATE
WITHIN THE NEXT FEW HOURS ALONG FRONT AND SURFACE TROUGH WITH
COVERAGE INCREASING THIS EVENING AS A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATE ACROSS THE REGION. RECENT TRENDS IN ARW/NMM HAVE BEEN
TO SHIFT MOST ORGANIZED THUNDERSTORM CLUSTER TO THE SOUTH ROUGHLY
ALONG AND SOUTH OF INTERSTATE 70. CURRENTLY THE ORIENTATION OF FLOW
ALOFT AND OTHER GUIDANCE STILL SHOWING THUNDERSTORM CLUSTERS
ORIGINATING FROM THE WEST OR NORTHWEST OF THIS. EITHER WAY...DEEP
MOIST AIR MASS AND DECENT INSTABILITY AHEAD OF FRONT WILL SUPPORT
ACTIVITY ACROSS MUCH OF CWA TRANSITIONING EASTWARD. STRONGEST CAPE
AXIS IF FURTHER EAST THAN PREVIOUS GUIDANCE INDICATED...THOUGH THERE
IS ENOUGH ELEVATED CAPE TO AT LEAST CONSIDER POTENTIAL FOR
MARGINALLY SEVERE HAIL. DCAPE 1000-1500 J/KG COINCIDING DRY ADIABATIC
PROFILES BELOW 700MB COULD SUPPORT ISOLATED SEVERE DOWNDRAFT
POTENTIAL DURING THE AFTERNOON...THOUGH AS MIXING RATIOS INCREASE
BELOW 700MB THIS EVENING THIS THREAT WILL LIKELY DIMINISH.
REGARDING FLASH FLOOD WATCH...ANOMALOUSLY HIGH PWAT VALUES 1.2-1.6
WILL ONLY INCREASE THROUGH THE NIGHT APPROACHING 1.7-1.8 WHICH IS
WELL WITHIN 99TH PERCENTILE OR 3 STANDARD DEVIATIONS FROM NORMAL.
WITH VERY SLOW STORM MOTIONS AND POSSIBILITY FOR
TRAINING/BACKBUILDING I AM COMFORTABLE WITH FLASH FLOOD WATCH. IF
ARW/NMM SOLUTION PANS OUT THEN WE MAY NEED TO CONSIDER ADDING
SOUTHERN PART OF FORECAST AREA TO WATCH.
MONDAY...WHILE FRONTAL PASSAGE SHOULD OCCUR FROM NORTH TO SOUTH
MONDAY...GUIDANCE IS SHOWING A LOT OF SPREAD ON TIMING. THIS LOWERS
CONFIDENCE/TIMING OF ADDITIONAL THUNDERSTORM ACTIVITY. ARW/NMM SHOW
A MORE ORGANIZED THUNDERSTORM CLUSTER DEVELOPING ALONG FRONT MONDAY
MORNING...THOUGH OTHER GUIDANCE IS SHOWING PREDOMINANTLY ISOLATED TO
SCATTERED ACTIVITY LINGERING ACROSS THE AREA. DEEP MOIST LAYER
REMAINS IN PLACE...SO WITH POTENTIAL FOR OVERRUNNING ALONG BAROCLINIC
ZONE...IT IS POSSIBLE FOR A MORE ORGANIZED CLUSTER IF WE CONTINUE TO
SEE WEAK HEIGHT FALL...WHICH COULD ALSO RESULT CONTINUING THREAT FOR
FLASH FLOODING. SEVERE THUNDERSTORM THREAT WILL BE HIGHLY DEPENDENT
ON FRONTAL POSITION/TIMING AS BETTER INSTABILITY WILL TEND TO BE
AHEAD OF FRONT. AS WITH TODAY...THREATS WOULD BE LARGE HAIL/DAMAGING
WINDS ALONG/SOUTH OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 252 PM MDT SUN AUG 16 2015
FOR THIS EXTENDED FORECAST PACKAGE...A STRONG COLD FRONT IS EXPECTED
TO MOVE THROUGH ON TUESDAY...BRINGING AN END TO SIGNIFICANT
PRECIPITATION CHANCES AND A TEMPORARY PARDON FROM THE WARMTH AND
HUMIDITY. ZONAL FLOW ALOFT RETURNS BEHIND TUESDAY`S SYSTEM. WITH
SOUTHERLY LOW LEVEL FLOW...A WARMING TREND IS EXPECTED TO BEGIN
THURSDAY. HOWEVER...YET ANOTHER UPPER LEVEL DISTURBANCE IS EXPECTED
TO FORCE A COLD FRONT THROUGH THIS WEEKEND...BRINING ANOTHER CHANCE
FOR BELOW NORMAL TEMPERATURES.
THE MOST IMPACTFUL WEATHER IN THE EXTENDED FORECAST PERIOD IS
ANTICIPATED MONDAY EVENING THROUGH TUESDAY EVENING. ACTIVE WEATHER
IS FORECAST AS A LARGE NEGATIVELY TILTED TROUGH KICKS OUT OVER THE
HIGH PLAINS. STRONG/SEVERE THUNDERSTORMS MAY BE ONGOING ACROSS
PORTIONS OF THE REGION MONDAY EVENING DEPENDING ON THE FRONT
LOCATION AND ENVIRONMENTAL PARAMETERS. ANY POTENTIAL SEVERE WEATHER
THREAT MAY BE HIGHER MONDAY EVENING AS INITIAL DEVELOPMENT IN
COLORADO SHOULD BE MOVING IN. THE PRIMARY THREATS FOR SEVERE WEATHER
WILL BE LARGE HAIL AND DAMAGING WINDS. AS MENTIONED IN THE DAY 2
STORM PREDICTION CENTER OUTLOOK...SURFACE VORTICITY/HELICITY
MAXIMIZED IN THE VICINITY OF THE FRONT MAY PROVIDE AN OPPORTUNITY
FOR A TORNADO TO OCCUR. CONFIDENCE IN THIS ISN`T AS HIGH AS HIGHER
RESOLUTION GUIDANCE INDICATES THE POTENTIAL FOR COLD POOL
DEVELOPMENT...HIGHLIGHTING A HIGHER THREAT OF MCS DEVELOPMENT WITH
DAMAGING WINDS AS THE MAIN THREAT. IN TERMS OF FLASH FLOODING...A
THREAT WILL STILL EXIST ESPECIALLY IF HEAVY RAINS ARE RECEIVED
TONIGHT. PRECIPITABLE WATER VALUES FALL AS THE FRONT DOES FORCE SOME
MOISTURE SOUTH SO WE NO LONGER EXPECT PRECIPITABLE WATER VALUES
NEARING THE 99TH PERCENTILE. STORM MOVEMENT REMAINS QUITE SLOW IN
TERMS OF STEERING WINDS ALOFT SO COLD POOL FORMATION/MOVEMENT SHOULD
BE THE PRIMARY DRIVER. THEREFORE...A FLASH FLOOD THREAT MAY PERSIST
AND ANOTHER FLASH FLOOD WATCH MAY BE NEEDED FOR MONDAY EVENING IN
LATER FORECAST PACKAGES.
ON TUESDAY...THE FRONT SHOULD FINALLY SLIDE ALL THE WAY THROUGH THE
REGION...RESTRICTING HIGHEST INSTABILITY SOUTH OF THE FRONT AND
PRIMARILY SOUTH OF THE REGION. HOWEVER...CONFIDENCE IS LOW ON WHEN
THIS COLD FRONT WILL SURGE SOUTH AND THERE MAY BE ENOUGH TIME FOR
STORM DEVELOPMENT AHEAD OF THE FRONT. THIS WOULD MEAN SEVERE WEATHER
IS POSSIBLE BUT UNLIKELY TUESDAY. HOWEVER...ADDITIONAL PERTURBATIONS
MOVE IN FROM THE NORTHWEST BEHIND THE MAIN FORCING AND WITH SOME
INSTABILITY REMAINING IN THE POST-FRONTAL ENVIRONMENT...THERE SHOULD
BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TUESDAY AFTERNOON BUT
COVERAGE AND INTENSITY REMAINS IN DOUBT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 536 PM MDT SUN AUG 16 2015
VFR TO IFR CONDITIONS FORECAST FOR THE 0Z TAFS. MAIN ISSUE IS
TIMING THE BEST WINDOW FOR STORMS TO MOVE OVER THE TAF SITES.
STORMS HAVE BEEN DEVELOPING VERY SPORADICALLY ALONG AND BEHIND A
COLD FRONT THAT IS SLOWLY MOVING SOUTH THROUGH THE AREA. LOOKS
LIKE THE BEST WINDOW OF OPPORTUNITY FOR STORMS OVER THE SITES WILL
BE THE EVENING HOURS. AFTER THAT CONFIDENCE IS LESS WHETHER STORMS
WILL BE OVER THE SITES SO HAVE VCTS UNTIL LATER IN THE NIGHT WHEN
ENVIRONMENT LOOKS LESS FAVORABLE FOR STORM COVERAGE.
MAIN THREAT WITH THESE STORMS WILL BE REDUCTION IN VISIBILITIES
DUE TO THE HEAVY RAINFALL. THOUGHT ABOUT PLACING A MENTION OF MVFR
VISIBILITY IN THE TEMPO GROUPS FOR THIS REASON...BUT AM NOT THAT
CONFIDENT THE REDUCED VISIBILITY FROM THE STORMS WILL BE LONG
ENOUGH TO WARRANT THAT LOW A MENTION IN THE TAFS. KMCK DID REPORT
VISIBILITIES AROUND 2 MILES DUE TO HEAVY RAINFALL FOR A FEW
MINUTES...SO WOULD EXPECT THESE BRIEF REDUCTIONS IN VISIBILITIES
IF HEAVY RAINFALL MOVES OVER THE SITES.
OVERNIGHT LOW CLOUDS WILL MOVE INTO THE AREA FROM THE NORTH
BRINGING MVFR TO POSSIBLY IFR CONDITIONS TO KMCK...BUT LOOKS TO REMAIN
NORTH OF KGLD AT THIS TIME. CEILINGS WILL REMAIN MVFR THROUGH
MOST OF THE MORNING.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR KSZ001>003-013-014.
CO...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR COZ090-091.
NE...FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR NEZ079>081.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
342 PM MDT SAT AUG 15 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 244 PM MDT SAT AUG 15 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE EXTENDING
FROM THE SOUTHERN PLAINS TO THE GREAT LAKES WITH A TROUGH ACROSS THE
PACIFIC NORTHWEST. SW FLOW IS IN PLACE ACROSS THE CENTRAL ROCKIES
AND NORTHERN PLAINS. AT THE SURFACE...SURFACE LOW PRESSURE IS IN
PLACE ACROSS EASTERN COLORADO WITH A COLD FRONT EXTENDING FROM THE
GREAT BASIN ACROSS WYOMING AND INTO WESTERN EXTENT OF NORTH DAKOTA.
THIS AFTERNOON-TONIGHT...SHORT RANGE/HI RES GUIDANCE INDICATES
THUNDERSTORM ACTIVITY INITIATING ALONG SURFACE TROUGH AND ACROSS
CHEYENNE RIDGE AND SLOWLY MOVING EASTWARD AS WEAK SHORTWAVE TROUGH
PROPAGATES THROUGH THE SOUTHERLY FLOW ACROSS THE ROCKIES. MOST
GUIDANCE IS SHOWING BETTER COVERAGE ACROSS THE NORTHWEST HALF OF THE
CWA THAT CORRELATES WITH BETTER FORCING. DEEP MOIST AIR MASS IN
PLACE...SLOWER STORM MOTIONS AND MODERATE INSTABILITY WILL SUPPORT
LOCALLY HEAVY RAINFALL WITH ANY ACTIVITY THAT DEVELOPS. CAPE VALUES
1500-3000 J/KG COULD SUPPORT A FEW STRONGER UPDRAFTS DESPITE MINIMAL
SHEER...WITH LARGE HAIL/ISOLATED DOWN DRAFTS MAIN SEVERE
THUNDERSTORM THREATS.
SUNDAY...UPPER LOW OVER THE PACIFIC NORTHWEST SHIFTS EAST WITH
FALLING HEIGHTS THROUGH THE AFTERNOON. COLD FRONT WILL BE AT LEAST
APPROACHING THE REGION BY THE AFTERNOON...WITH FASTER GUIDANCE
SHOWING FROPA BY MIDDAY. INCREASING FORCING AND DEEP MOISTURE WILL
SUPPORT INCREASING SHOWER/THUNDERSTORM COVERAGE. MODERATE
CAPE...INCREASING EFFECTIVE SHEER WILL COINCIDE IN BETTER CHANCE FOR
SEVERE THUNDERSTORMS BY THE LATE AFTERNOON PERIOD.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 342 PM MDT SAT AUG 15 2015
FOR THE EXTENDED FORECAST PERIOD...BIG CHANGES ARE ON THE WAY IN
TERMS OF COOLER TEMPERATURES AND LESS HUMIDITY AFTER A TUESDAY COLD
FRONT PASSAGE. AHEAD OF THE COLD FRONT...A PERIOD OF STORMS APPEARS
LIKELY FROM SUNDAY NIGHT THROUGH TUESDAY AS UPPER LEVEL DISTURBANCES
EJECT ACROSS THE HIGH PLAINS.
BEGINNING WITH SUNDAY NIGHT...WIDESPREAD THUNDERSTORM ACTIVITY IS
EXPECTED. STORMS INITIALLY DEVELOP ALONG A SLOW MOVING FRONTAL
BOUNDARY BEFORE CRAWLING EAST THROUGH SUNDAY EVENING. SLOW STORM
MOTIONS...AT OR BELOW 10 KNOTS...MODERATE INSTABILITY AND
PRECIPITABLE WATER VALUES NEAR 1.80 INCHES INDICATE A FLASH FLOOD
THREAT...ESPECIALLY FOR STORMS THAT TRAIN. SHEAR PARAMETERS ARE NOT
OVERLY IMPRESSIVE BUT SHOULD BE SUFFICIENT FOR ORGANIZED
THUNDERSTORM ACTIVITY. LARGE HAIL AND DAMAGING WINDS APPEAR TO BE
THE PRIMARY SEVERE PARAMETERS BUT FLASH FLOODING MAY BE THE MORE
SIGNIFICANT THREAT TO MONITOR.
ON MONDAY...ANOTHER LEAD SHORTWAVE TROUGH AHEAD OF A MORE
SUBSTANTIAL LONGWAVE TROUGH EJECTS TO CONTINUE THE STORMY PATTERN.
INSTABILITY BUILDS UP ONCE AGAIN BUT WIND SHEAR IS MORE SUBSTANTIAL
MONDAY. HOWEVER...THERE MAY BE STRATUS AND FOG MONDAY MORNING WITH A
STALLED FRONT IN THE REGION. THIS WOULD LEAD TO A MORE STABLE
ATMOSPHERE DEPENDING ON AMOUNT OF SUNLIGHT RECEIVED. A LITTLE UNSURE
ON HOW SUBSTANTIAL A SEVERE THREAT WOULD DEVELOP BECAUSE OF
FOG/STRATUS AND CONVECTIVE OVERTURNING. THE STORM PREDICTION CENTER
HAS ISSUED A SLIGHT RISK FOR SEVERE WEATHER ON MONDAY AND AGREE WITH
THEIR ASSESSMENT. AS FOR HEAVY RAINFALL POTENTIAL...PRECIPITABLE
WATER VALUES ARE LOWER THAN SUNDAY EVENING. HOWEVER...SLOW STORM
MOTIONS SHOULD CONTRIBUTE TO AT LEAST SOME HEAVY RAINFALL THREAT.
DEPENDING ON PRECIPITATION RECEIVED SUNDAY EVENING...FLASH FLOODING
MAY BECOME MORE LIKELY IF SOILS ARE SATURATED.
TUESDAY...THE PRIMARY DISTURBANCE WILL PUSH THROUGH...FORCING THE
FRONT COMPLETELY THROUGH THE REGION. THE QUESTION OF TIMING REMAINS
BUT A LATER EJECTION...AS SHOWN WITH LATEST EUROPEAN AND CANADIAN
GUIDANCE...WOULD FAVOR A MORE SUBSTANTIAL SEVERE WEATHER THREAT ONCE
AGAIN. BEHIND THIS FRONT...ANTICIPATE NOTICEABLY COOLER TEMPERATURES
AND LOWERED RELATIVE HUMIDITY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 108 PM MDT SAT AUG 15 2015
REGARDING EARLIER TAF UPDATE...MAIN AVIATION CONCERN WILL BE
POTENTIAL FOR THUNDERSTORMS LATE THIS AFTERNOON THROUGH THE TAF
PERIOD. SHORT RANGE GUIDANCE FAVORS ACTIVITY PRIMARILY ALONG
KS/CO BORDER SO I LEFT MENTION OUT OF KMCK. THERE COULD STILL BE A
FEW THUNDERSTORMS AT BOTH TAFS SITES THROUGH THE PERIOD AS A FRONT
APPROACHES FROM THE NORTH BY SUNDAY...SO WILL NEED TO MONITOR
TRENDS. MVFR VIS MAY DEVELOP AT KGLD AROUND SUNRISE SUNDAY AS GOOD
MOISTURE LINGERS. NOT A LOT OF CONFIDENCE AS BL WINDS MAY BE
STRONG ENOUGH TO MIX OUT OF THE LOW LEVELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...RRH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
244 PM MDT SAT AUG 15 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 244 PM MDT SAT AUG 15 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE EXTENDING
FROM THE SOUTHERN PLAINS TO THE GREAT LAKES WITH A TROUGH ACROSS THE
PACIFIC NORTHWEST. SW FLOW IS IN PLACE ACROSS THE CENTRAL ROCKIES
AND NORTHERN PLAINS. AT THE SURFACE...SURFACE LOW PRESSURE IS IN
PLACE ACROSS EASTERN COLORADO WITH A COLD FRONT EXTENDING FROM THE
GREAT BASIN ACROSS WYOMING AND INTO WESTERN EXTENT OF NORTH DAKOTA.
THIS AFTERNOON-TONIGHT...SHORT RANGE/HI RES GUIDANCE INDICATES
THUNDERSTORM ACTIVITY INITIATING ALONG SURFACE TROUGH AND ACROSS
CHEYENNE RIDGE AND SLOWLY MOVING EASTWARD AS WEAK SHORTWAVE TROUGH
PROPAGATES THROUGH THE SOUTHERLY FLOW ACROSS THE ROCKIES. MOST
GUIDANCE IS SHOWING BETTER COVERAGE ACROSS THE NORTHWEST HALF OF THE
CWA THAT CORRELATES WITH BETTER FORCING. DEEP MOIST AIR MASS IN
PLACE...SLOWER STORM MOTIONS AND MODERATE INSTABILITY WILL SUPPORT
LOCALLY HEAVY RAINFALL WITH ANY ACTIVITY THAT DEVELOPS. CAPE VALUES
1500-3000 J/KG COULD SUPPORT A FEW STRONGER UPDRAFTS DESPITE MINIMAL
SHEER...WITH LARGE HAIL/ISOLATED DOWN DRAFTS MAIN SEVERE
THUNDERSTORM THREATS.
SUNDAY...UPPER LOW OVER THE PACIFIC NORTHWEST SHIFTS EAST WITH
FALLING HEIGHTS THROUGH THE AFTERNOON. COLD FRONT WILL BE AT LEAST
APPROACHING THE REGION BY THE AFTERNOON...WITH FASTER GUIDANCE
SHOWING FROPA BY MIDDAY. INCREASING FORCING AND DEEP MOISTURE WILL
SUPPORT INCREASING SHOWER/THUNDERSTORM COVERAGE. MODERATE
CAPE...INCREASING EFFECTIVE SHEER WILL COINCIDE IN BETTER CHANCE FOR
SEVERE THUNDERSTORMS BY THE LATE AFTERNOON PERIOD.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 229 AM MDT SAT AUG 15 2015
TUESDAY AFTERNOON INTO THE EVENING IS THE ONLY DAY TO HAVE ANY
SIGNIFICANT CHANCES FOR PRECIPITATION OR STORMS. THERE IS A VERY
SUBSTANTIAL TROUGH MOVING INTO MONTANA AND WYOMING...AS WELL AS
THE NORTHERN HIGH PLAINS TUESDAY AT 12Z. THE GFS AND EUROPEAN ARE
IN FAIRLY GOOD AGREEMENT. ALONG WITH THIS TROUGH THERE IS A VERY
STRONG SHORTWAVE AT 700MB. SURFACE CAPES ARE UP TO 1500 J/KG...THE
BULK SHEAR IS NOT IMPRESSIVE. AT 18Z TUESDAY THE BULK SHEAR OVER
THE CWA IS REACHING TO 60 PLUS KTS AND CAPES ARE REACHING UP INTO
THE 2000 J/KG RANGE. CHANCES FOR STORMS ARE POSSIBLE AT BOTH 12Z
AND 18Z. STORMS ARE STILL POSSIBLE AT 00Z WEDNESDAY...HOWEVER
CAPES ARE NOT IMPRESSIVE BUT THERE IS STRONG BULK SHEAR AROUND 60
KTS. AFTER 06Z WEDNESDAY STORMS WILL START TO MOVE EAST OUT OF OUR
REGION.
FOR THE REMAINDER OF THE LONG TERM THE CWA WILL BE DRIER WITH LOW TO
NO CHANCES FOR PRECIPITATION. BY FRIDAY THERE WILL BE A ZONAL FLOW
OVER THE MAJORITY OF THE US. AS FAR AS TEMPERATURES GO...THERE WILL
BE A DECREASE IN HIGH TEMPERATURES WEDNESDAY AND LOW TEMPERATURES
TUESDAY AND WEDNESDAY NIGHTS. THIS IS DUE TO A COLD FRONT MOVING
THROUGH THE CWA. TEMPERATURES WILL DROP INTO THE HIGH 70S ACROSS THE
REGION WEDNESDAY AND INTO THE LOW TO MID 50S TUESDAY AND WEDNESDAY
NIGHT. AFTER THIS HIGH TEMPERATURES WILL START TO INCREASE AGAIN
INTO THE MID TO HIGH 80S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 108 PM MDT SAT AUG 15 2015
REGARDING EARLIER TAF UPDATE...MAIN AVIATION CONCERN WILL BE
POTENTIAL FOR THUNDERSTORMS LATE THIS AFTERNOON THROUGH THE TAF
PERIOD. SHORT RANGE GUIDANCE FAVORS ACTIVITY PRIMARILY ALONG
KS/CO BORDER SO I LEFT MENTION OUT OF KMCK. THERE COULD STILL BE A
FEW THUNDERSTORMS AT BOTH TAFS SITES THROUGH THE PERIOD AS A FRONT
APPROACHES FROM THE NORTH BY SUNDAY...SO WILL NEED TO MONITOR
TRENDS. MVFR VIS MAY DEVELOP AT KGLD AROUND SUNRISE SUNDAY AS GOOD
MOISTURE LINGERS. NOT A LOT OF CONFIDENCE AS BL WINDS MAY BE
STRONG ENOUGH TO MIX OUT OF THE LOW LEVELS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...CLT
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GRAY ME
527 PM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK SURFACE TROUGH WILL CROSS THE REGION THIS EVENING ACCOMPANIED
BY SHOWERS AND A FEW THUNDERSTORMS. A LARGE RIDGE OF HIGH PRESSURE
WILL BUILD ALONG THE EAST COAST SUNDAY THROUGH MID NEXT WEEK
BRINGING HOT AND HUMID AIR TO THE AREA. LOW PRESSURE WILL MOVE
NORTH OF OUR REGION AND INTO CANADA LATER IN THE WEEK...SLOWLY
DRAGGING A COLD FRONT ACROSS THE REGION.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MINIMAL DYNAMICS WITH TROUGH CROSSING THE FORECAST AREA THIS
EVENING...WILL COMBINE WITH AN UNSTABLE...HIGH CAPE ENVIRONMENT TO
PRODUCE MORE SHOWERS AND THUNDERSTORMS. A FEW OF THESE STORMS MAY
CONTAIN GUSTY WINDS...AND SLOW MOVING NATURE TO THE PRECIP MAY
LEAD TO LOCALLY HEAVY RAINFALL. BOUNDARIES WILL CONTINUE TO FORM
AS WELL...THEREFORE CONVECTIVE DEVELOPMENT WILL CONTINUE ACROSS
THESE REGIONS FOR UP TO A FEW MORE HOURS.
THE LATEST HRRR CONTINUES TO SHOW INDIVIDUAL CELLS BECOMING
EMBEDDED IN A LARGER SCALE MASS OF RAIN TOWARDS THIS EVENING. THE
PRECIP WILL GRADUALLY WIND DOWN THIS EVENING AS THE UPPER LEVEL
TROUGH EXITS THE REGION AND DIURNAL HEATING CEASES.
EXPECT PATCHY FOG TO FORM. THIS WILL MAINLY BE OVER THE INLAND
VALLEY LOCATIONS.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
HHH...HAZY HOT AND HUMID CONDITIONS ARE EXPECTED ON SUNDAY AS H8
TEMPERATURES REACH +16C. A LARGE UPPER LEVEL RIDGE WILL BE IN
PLACE AT THAT TIME...WITH THE MEAN FLOW OUT OF THE SOUTHWEST.
TEMPERATURES WILL RANGE FROM THE MID 80S IN THE MOUNTAINS...TO THE
LOWER 90S OVER SOUTHERN MAINE AND NEW HAMPSHIRE. DEW POINT VALUES
WILL BE IN THE MID 60S...SO HEAT INDEX VALUES SHOULD NOT BE OVERLY
HIGH.
EXPECT MORE PATCHY FOG SUNDAY NIGHT. TEMPERATURES WILL FALL TO
THEIR DEW POINTS SO READINGS WILL DROP INTO THE MID 60S BY
SUNRISE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
LONG RANGE GLOBAL MODELS ARE IN GOOD AGREEMENT THROUGH THE
PERIOD. AN EAST COAST RIDGE AT THE SURFACE AND ALOFT WILL RESULT
IN ONE OF THE HOTTEST DAYS OF THE SUMER ON MONDAY. WITH DEWPOINTS
IN THE MID TO UPPER 60S APPARENT TEMPERATURES WILL BE IN THE 90S
OVER MUCH OF THE AREA AWAY FROM THE IMMEDIATE COAST. A CAP ALOFT
SHOULD PREVENT MUCH IN THE WAY OF CONVECTION.
TEMPERATURES WILL COOL A FEW DEGREES TUESDAY AND THEN A FEW
DEGREES MORE ON WEDNESDAY. AS THE RIDGE BREAKS DOWN WE WILL SEE
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. A COLD FRONT
WILL APPROACH LATE WEEK WHICH COULD SIGNAL A MORE ORGANIZED
CONVECTION EVENT.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MAINLY VFR CONDITIONS THROUGH SUNDAY NIGHT. THE
EXCEPTION WILL BE FOR LOCAL IFR CONDITIONS IN ANY STORMS THROUGH
THIS EVENING. ALSO...PATCHY LATE NIGHT FOG WILL LEAD TO LOCAL IFR
CONDITIONS...ESPECIALLY IN THE INLAND VALLEYS.
LONG TERM...VFR TO MVFR CONDITIONS ARE EXPECTED THROUGH MUCH THE
EXTENDED PERIOD WITH LOCALIZED IFR CONDITIONS IN ANY THUNDERSTORMS
TUESDAY THROUGH THURSDAY.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS DURING THE NEAR AND SHORT RANGE PORTION OF THE
FORECAST. SOME FOG AND HAZE MAY DEVELOP OVER THE WATERS AS
INCREASINGLY WARM...HUMID AIR CROSSES THE REGION.
LONG TERM...WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS DURING THE LONG TERM PORTION OF THE FORECAST. LOCALIZED
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TUESDAY THROUGH THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CANNON/LULOFS
NEAR TERM...CANNON
SHORT TERM...CANNON
LONG TERM...LULOFS
AVIATION...CANNON
MARINE...CANNON/LULOFS
AREA FORECAST DISCUSSION
NWS GRAY ME
242 PM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK SURFACE TROUGH WILL CROSS THE REGION THIS EVENING ACCOMPANIED
BY SHOWERS AND A FEW THUNDERSTORMS. A LARGE RIDGE OF HIGH PRESSURE
WILL BUILD ALONG THE EAST COAST SUNDAY THROUGH MID NEXT WEEK
BRINGING HOT AND HUMID AIR TO THE AREA. LOW PRESSURE WILL MOVE
NORTH OF OUR REGION AND INTO CANADA LATER IN THE WEEK...SLOWLY
DRAGGING A COLD FRONT ACROSS THE REGION.
&&
.NEAR TERM /THROUGH TONIGHT/...
MINIMAL DYNAMICS WITH TROUGH CROSSING THE FORECAST AREA THIS
EVENING...WILL COMBINE WITH AN UNSTABLE...HIGH CAPE ENVIRONMENT TO
PRODUCE MORE SHOWERS AND THUNDERSTORMS. A FEW OF THESE STORMS MAY
CONTAIN GUSTY WINDS...AND SLOW MOVING NATURE TO THE PRECIP MAY
LEAD TO LOCALLY HEAVY RAINFALL. BOUNDARY`S CONTINUE TO FORM AS
WELL...THEREFORE CONVECTIVE DEVELOPMENT WILL FORM ACROSS THESE
REGIONS.
THE LATEST HRRR CONTINUES TO SHOW INDIVIDUAL CELLS BECOMING
EMBEDDED IN A LARGER SCALE MASS OF RAIN TOWARDS THIS EVENING. THE
PRECIP WILL GRADUALLY WIND DOWN THIS EVENING. AS THE UPPER LEVEL
TROUGH EXITS THE REGION AND DIURNAL HEATING CEASES.
EXPECT PATCHY FOG TO FORM. THIS WILL MAINLY BE OVER THE INLAND
VALLEY LOCATIONS.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
HHH...HAZY HOT AND HUMID CONDITIONS ARE EXPECTED ON SUNDAY AS H8
TEMPERATURES REACH +16C. A LARGE UPPER LEVEL RIDGE WILL BE IN
PLACE AT THAT TIME...WITH THE MEAN FLOW OUT OF THE SOUTHWEST.
TEMPERATURES WILL RANGE FROM THE MID 80S IN THE MOUNTAINS...TO THE
LOWER 90S OVER SOUTHERN MAINE AND NEW HAMPSHIRE. DEW POINT VALUES
WILL BE IN THE MID 60S...SO HEAT INDEX VALUES SHOULD NOT BE OVERLY
HIGH.
EXPECT MORE PATCHY FOG SUNDAY NIGHT. TEMPERATURES WILL FALL TO
THEIR DEW POINTS SO READINGS WILL DROP INTO THE MID 60S BY
SUNRISE.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
LONG RANGE GLOBAL MODELS ARE IN GOOD AGREEMENT THROUGH THE
PERIOD. AN EAST COAST RIDGE AT THE SURFACE AND ALOFT WILL RESULT
IN ONE OF THE HOTTEST DAYS OF THE SUMER ON MONDAY. WITH DEWPOINTS
IN THE MID TO UPPER 60S APPARENT TEMPERATURES WILL BE IN THE 90S
OVER MUCH OF THE AREA AWAY FROM THE IMMEDIATE COAST. A CAP ALOFT
SHOULD PREVENT MUCH IN THE WAY OF CONVECTION.
TEMPERATURES WILL COOL A FEW DEGREES TUESDAY AND THEN A FEW
DEGREES MORE ON WEDNESDAY. AS THE RIDGE BREAKS DOWN WE WILL SEE
INCREASING CHANCES OF SHOWERS AND THUNDERSTORMS. A COLD FRONT
WILL APPROACH LATE WEEK WHICH COULD SIGNAL A MORE ORGANIZED
CONVECTION EVENT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
SHORT TERM...MAINLY VFR CONDITIONS THROUGH SUNDAY NIGHT. THE
EXCEPTION WILL BE FOR LOCAL IFR CONDITIONS IN ANY STORMS THROUGH
THIS EVENING. ALSO...PATCHY LATE NIGHT FOG WILL LEAD TO LOCAL IFR
CONDITIONS...ESPECIALLY IN THE INLAND VALLEYS.
LONG TERM...VFR TO MVFR CONDITIONS ARE EXPECTED THROUGH MUCH THE
EXTENDED PERIOD WITH LOCALIZED IFR CONDITIONS IN ANY THUNDERSTORMS
TUESDAY THROUGH THURSDAY.
&&
.MARINE...
SHORT TERM...WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS DURING THE NEAR AND SHORT RANGE PORTION OF THE
FORECAST. SOME FOG AND HAZE MAY DEVELOP OVER THE WATERS AS
INCREASINGLY WARM...HUMID AIR CROSSES THE REGION.
LONG TERM...WINDS AND SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
THRESHOLDS DURING THE LONG TERM PORTION OF THE FORECAST. LOCALIZED
SHOWERS AND THUNDERSTORMS ARE POSSIBLE TUESDAY THROUGH THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...CANNON/LULOFS
NEAR TERM...CANNON
SHORT TERM...CANNON
LONG TERM...LULOFS
AVIATION...CANNON
MARINE...CANNON/LULOFS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
1051 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH ACROSS THE AREA TODAY. HIGH
PRESSURE WILL BUILD ACROSS THE REGION SUNDAY INTO MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
1045 AM UPDATE...A WEAK BOUNDARY CURRENTLY STRETCHES FROM ROUGHLY
HOULTON TO NORTH OF GREENVILLE. WE`RE JUST STARTING TO SEE SOME
ISOLATED SHOWERS POP UP ON RADAR ACROSS THE HIGHER TERRAIN IN
WESTERN MAINE IN THE VICINITY OF THIS FRONT. EXPECT THESE SHOWERS
WILL BECOME MORE NUMEROUS THIS AFTERNOON WITH DAYTIME HEATING.
THERE`LL BE PLENTY OF INSTABILITY FOR THUNDERSTORMS AS WELL. THE
LATEST HRRR GUIDANCE SHOWS A FAIR AMOUNT OF ACTIVITY DEVELOPING
AHEAD OF THE FRONT BY EARLY AFTERNOON, SO HAVE INCREASED POPS A
BIT TO LIKELY OVER THE CENTRAL HIGHLANDS AND INTERIOR DOWNEAST.
NOTE THAT THE SHOWERS AND THUNDERSTORMS WILL BE SLOW MOVERS WITH
MINIMAL FLOW. THIS COMBINED WITH PLENTIFUL MOISTURE (PWATS OF 1.5
TO 1.75 INCHES), FEEL HEAVY RAIN WILL BE A THREAT WITH ANY
THUNDERSTORMS. THIS HAS BEEN ADDED TO THE FORECAST. OTHERWISE, THE
FORECAST IS IN GOOD SHAPE AND NO OTHER CHANGES WERE NEEDED.
PREVIOUS DISCUSSION...A WEAK SURFACE TROUGH PUSHING SOUTH ACROSS
THE REGION WILL BRING SOME SCATTERED SHOWERS TODAY, MAINLY TO
CENTRAL PARTS OF THE AREA THIS MORNING THEN DOWNEAST THIS
AFTERNOON. SOME SURFACE FRONTAL CONVERGENCE WORKING WITH CAPES UP
TO 1000 J/KG AND SOME HEATING WILL PRODUCE A FEW THUNDERSTORMS
OVER DOWNEAST AREAS THIS AFTERNOON. THERE COULD BE SOME BRIEF,
LOCALLY HEAVY DOWNPOURS. HOWEVER, WITH WINDS LIGHT BOTH ALOFT AND
AT THE SURFACE, SEVERE STORMS ARE NOT EXPECTED. SKIES WILL BECOME
PARTLY SUNNY OVER THE NORTH. ANY SHOWERS WILL DISSIPATE LATE TODAY
AS THE FRONT PUSHES OFFSHORE. TONIGHT WILL BECOME CLEAR. SOME
ISOLATED POCKETS OF PATCHY FOG ARE POSSIBLE IN SOME VALLEY AREAS
TOWARD MORNING.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SURFACE/UPPER LEVEL HIGH PRESSURE WILL BUILD ACROSS THE REGION
SUNDAY THROUGH MONDAY WITH MOSTLY CLEAR SKIES. A COLD FRONT WILL
APPROACH NORTHERN MAINE LATER MONDAY NIGHT. CLOUD COVER WILL
INCREASE ACROSS NORTHERN AREAS MONDAY NIGHT...WITH A SLIGHT CHANCE
OF SHOWERS LATE. MOSTLY CLEAR SKIES ARE EXPECTED DOWNEAST MONDAY
NIGHT. TEMPERATURES WILL BE AT ABOVE NORMAL LEVELS SUNDAY/MONDAY.
SOME LOCATIONS WILL REACH 90 DEGREES FOR THE FIRST TIME THIS
SUMMER MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE COLD FRONT WILL STALL ACROSS THE REGION TUESDAY THROUGH
TUESDAY NIGHT THEN BEGIN TO LIFT BACK NORTH IN THE FORM OF A WARM
FRONT WEDNESDAY. EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS ACROSS
THE FORECAST AREA BOTH TUESDAY AND WEDNESDAY. THE WARM FRONT LIFTS
NORTH OF MAINE THURSDAY. EXPECT PARTLY/MOSTLY CLOUDY SKIES ACROSS
NORTHERN PORTIONS OF THE FORECAST AREA THURSDAY...WITH PARTLY
CLOUDY SKIES ACROSS THE REST OF THE REGION. COULD ALSO STILL HAVE
A CHANCE OF SHOWERS THURSDAY. UNCERTAINTY THEN EXISTS REGARDING
THE TIMING OF A COLD FRONT FRIDAY. THE MORE PROGRESSIVE MODEL
SOLUTIONS BRING THE FRONT ACROSS THE REGION FRIDAY WITH A CHANCE
OF SHOWERS/THUNDERSTORMS...WHILE THE SLOWER SOLUTIONS KEEP THE
FRONT WEST OF THE REGION INTO SATURDAY. HAVE INCLUDED A CHANCE OF
SHOWERS/THUNDERSTORMS FRIDAY...THOUGH THIS WILL BE DEPENDENT ON
THE EVENTUAL TIMING OF THE FRONT. TEMPERATURES WILL REMAIN AT
SLIGHTLY ABOVE NORMAL LEVELS TUESDAY THROUGH THURSDAY...WITH NEAR
NORMAL LEVEL TEMPERATURES FRIDAY.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS ARE EXPECTED TODAY INTO TONIGHT WITH
THE POSSIBLE BRIEF EXCEPTIONS OF THUNDERSHOWERS DOWNEAST THIS
AFTERNOON AND PATCHY FOG LATE TONIGHT.
SHORT TERM: VFR CONDITIONS ARE EXPECTED ACROSS THE REGION SUNDAY
THROUGH MONDAY. VARIABLE CONDITIONS ARE POSSIBLE WITH ANY SHOWERS
OR THUNDERSTORMS TUESDAY INTO WEDNESDAY. OTHERWISE...VFR
CONDITIONS ARE EXPECTED TUESDAY AND WEDNESDAY.
&&
.MARINE...
NEAR TERM: THERE MAY BE A THUNDERSHOWER ALONG COASTAL AREAS THIS
AFTERNOON. OTHERWISE, WINDS WILL BE LIGHT TODAY AND TONIGHT.
SHORT TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS SUNDAY THROUGH MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...BLOOMER/HASTINGS
SHORT TERM...NORCROSS
LONG TERM...NORCROSS/DUMONT
AVIATION...BLOOMER/HASTINGS/NORCROSS
MARINE...BLOOMER/HASTINGS/NORCROSS
AREA FORECAST DISCUSSION
NWS CARIBOU ME
620 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE SOUTH ACROSS THE AREA TODAY. HIGH
PRESSURE WILL BUILD ACROSS THE REGION SUNDAY INTO MONDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
6:20 AM UPDATE...ISOLATED SHOWERS WERE ADDED TO NORTH CENTRAL
AREAS WHERE THE LATEST HRRR MODEL GUIDANCE IS SHOWING SOME VERY
SMALL SPOTTY SHOWERS. PRECIPITATION CHANCES WERE DECREASED FROM
NUMEROUS SHOWERS TO SCATTERED SHOWERS DOWNEAST WHERE SOME SHOWERS
ARE EXPECTED, BUT WITH LESS COVERAGE THAT PREVIOUSLY EXPECTED.
A WEAK SURFACE TROUGH PUSHING SOUTH ACROSS THE REGION WILL BRING
SOME SCATTERED SHOWERS TODAY, MAINLY TO CENTRAL PARTS OF THE
AREA THIS MORNING THEN DOWNEAST THIS AFTERNOON. SOME SURFACE
FRONTAL CONVERGENCE WORKING WITH CAPES UP TO 1000 J/KG AND SOME
HEATING WILL PRODUCE A FEW THUNDERSTORMS OVER DOWNEAST AREAS THIS
AFTERNOON. THERE COULD BE SOME BRIEF, LOCALLY HEAVY DOWNPOURS.
HOWEVER, WITH WINDS LIGHT BOTH ALOFT AND AT THE SURFACE, SEVERE
STORMS ARE NOT EXPECTED. SKIES WILL BECOME PARTLY SUNNY OVER THE
NORTH. ANY SHOWERS WILL DISSIPATE LATE TODAY AS THE FRONT PUSHES
OFFSHORE. TONIGHT WILL BECOME CLEAR. SOME ISOLATED POCKETS OF
PATCHY FOG ARE POSSIBLE IN SOME VALLEY AREAS TOWARD MORNING.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
SURFACE/UPPER LEVEL HIGH PRESSURE WILL BUILD ACROSS THE REGION
SUNDAY THROUGH MONDAY WITH MOSTLY CLEAR SKIES. A COLD FRONT WILL
APPROACH NORTHERN MAINE LATER MONDAY NIGHT. CLOUD COVER WILL
INCREASE ACROSS NORTHERN AREAS MONDAY NIGHT...WITH A SLIGHT CHANCE
OF SHOWERS LATE. MOSTLY CLEAR SKIES ARE EXPECTED DOWNEAST MONDAY
NIGHT. TEMPERATURES WILL BE AT ABOVE NORMAL LEVELS SUNDAY/MONDAY.
SOME LOCATIONS WILL REACH 90 DEGREES FOR THE FIRST TIME THIS
SUMMER MONDAY.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
THE COLD FRONT WILL STALL ACROSS THE REGION TUESDAY THROUGH
TUESDAY NIGHT THEN BEGIN TO LIFT BACK NORTH IN THE FORM OF A WARM
FRONT WEDNESDAY. EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS ACROSS
THE FORECAST AREA BOTH TUESDAY AND WEDNESDAY. THE WARM FRONT LIFTS
NORTH OF MAINE THURSDAY. EXPECT PARTLY/MOSTLY CLOUDY SKIES ACROSS
NORTHERN PORTIONS OF THE FORECAST AREA THURSDAY...WITH PARTLY
CLOUDY SKIES ACROSS THE REST OF THE REGION. COULD ALSO STILL HAVE
A CHANCE OF SHOWERS THURSDAY. UNCERTAINTY THEN EXISTS REGARDING
THE TIMING OF A COLD FRONT FRIDAY. THE MORE PROGRESSIVE MODEL
SOLUTIONS BRING THE FRONT ACROSS THE REGION FRIDAY WITH A CHANCE
OF SHOWERS/THUNDERSTORMS...WHILE THE SLOWER SOLUTIONS KEEP THE
FRONT WEST OF THE REGION INTO SATURDAY. HAVE INCLUDED A CHANCE OF
SHOWERS/THUNDERSTORMS FRIDAY...THOUGH THIS WILL BE DEPENDENT ON
THE EVENTUAL TIMING OF THE FRONT. TEMPERATURES WILL REMAIN AT
SLIGHTLY ABOVE NORMAL LEVELS TUESDAY THROUGH THURSDAY...WITH NEAR
NORMAL LEVEL TEMPERATURES FRIDAY.
&&
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: VFR CONDITIONS ARE EXPECTED TODAY INTO TONIGHT WITH
THE POSSIBLE BRIEF EXCEPTIONS OF THUNDERSHOWERS DOWNEAST THIS
AFTERNOON AND PATCHY FOG LATE TONIGHT.
SHORT TERM: VFR CONDITIONS ARE EXPECTED ACROSS THE REGION SUNDAY
THROUGH MONDAY. VARIABLE CONDITIONS ARE POSSIBLE WITH ANY SHOWERS
OR THUNDERSTORMS TUESDAY INTO WEDNESDAY. OTHERWISE...VFR
CONDITIONS ARE EXPECTED TUESDAY AND WEDNESDAY.
&&
.MARINE...
NEAR TERM: THERE MAY BE A THUNDERSHOWER ALONG COASTAL AREAS THIS
AFTERNOON. OTHERWISE, WINDS WILL BE LIGHT TODAY AND TONIGHT.
SHORT TERM: WINDS/SEAS WILL REMAIN BELOW SMALL CRAFT ADVISORY
LEVELS SUNDAY THROUGH MONDAY NIGHT.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...BLOOMER
SHORT TERM...NORCROSS
LONG TERM...NORCROSS/DUMONT
AVIATION...BLOOMER/NORCROSS
MARINE...BLOOMER/NORCROSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
116 PM EDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 456 AM EDT SAT AUG 15 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO
THE UPPER MS VALLEY RESULTING IN NRLY MID/UPPER LEVEL FLOW THROUGH
THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDED FROM QUEBEC
THROUGH THE NRN LAKES INTO THE CNTRL PLAINS. ALTHOUGH MAINLY CLEAR
SKIES PREVAILED ACROSS UPPER MI...FAVORABLE RADIATIONAL COOLING HAS
ALLOWED PATCHY SHALLOW FOG TO DEVELOP.
TODAY...WITH THE RIDGE AND STRONG CAPPING OVER THE AREA...DRY
WEATHER IS EXPECTED. MIXING TO NEAR 850 MB TEMPS THAT CLIMB TO
AROUND 20C SUPPORTS TEMPS NEAR 90 OVER THE WEST HALF OF THE CWA.
LIGHT SRLY FLOW WILL KEEP TEMPS CLOSER TO 80 NEAR LAKE MI. OVER THE
NORTH...LAKE BREEZES DURING THE AFTERNOON WILL BRING LIMITED RELIEF
WITH TEMPS STILL INTO THE LOWER TO MID 80S NEAR LAKE SUPERIOR.
TONIGHT...WARM AND MORE HUMID CONDITIONS WILL PREVAIL AS INCREASING
SW WINDS DRAW MORE MOISTURE INTO THE REGION. BOUNDARY LAYER WINDS TO
AROUND 20 KNOTS AND ASSOCIATED MIXING WILL KEEP TEMPS MAINLY IN THE
60S...EXCEPT LOWER 70S FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 421 AM EDT SAT AUG 15 2015
SUNDAY...ONE LAST WARM AND HUMID DAY IS IN STORE BEFORE SEASONABLY
COOL CONDITIONS TAKE OVER FOR THE WORK WEEK. 850 HPA TEMPS NEARING
20C COMBINED WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES WILL RESULT IN
TEMPS WELL INTO THE 80S AND LOW 90S ACROSS THE CWA. DECENT SW
GRADIENT FLOW WILL KEEP THE LAKE SUPERIOR LAKE BREEZE
OFFSHORE...RESULTING IN SW DOWNSLOPE LOCATIONS POTENTIALLY REACHING
THE LOW 90S. AN APPROACHING SFC COLD FRONT ASSOCIATED WITH A SFC LOW
TRACKING ACROSS NORTHERN ONTARIO WILL BE NEARING THE WESTERN CWA
DURING THE AFTERNOON. SOME MODEL GUIDANCE IS INDICATING A FEW
SHOWERS AND STORMS MAY DEVELOP ACROSS THE FAR WEST LATE IN THE
AFTERNOON...BUT CAPPING BETWEEN 750 AND 850 HPA ALONG WITH MINIMAL
FORCING SHOULD EITHER INHIBIT PRECIP DEVELOPMENT...OR DESTROY ANY
APPROACHING PRECIP.
SUNDAY NIGHT THROUGH MONDAY NIGHT...THE SFC COLD FRONT WILL BE
NEARING OR ENTERING WESTERN UPPER MI AT 00Z MONDAY. AS SUNDAY NIGHT
PROGRESSES...AN ACTIVE RIGHT ENTRANCE TO A 120KT UPPER JET WILL
ALIGN WITH A QUICK-MOVING SHORTWAVE FROM THE NORTHERN PLAINS TO
PRODUCE A SHORT...BUT POTENT STRIP OF FORCING ACROSS THE WEST AND
CENTRAL CWA. MUCAPE APPROACHING 1000 J/KG AND 0-6KM SHEAR OF 30 TO
40 KTS SUPPORT A CHANCE OF STRONG STORMS ACROSS THE WEST IN THE
EVENING AS THIS FORCING INCREASES. LARGE HAIL IS THE PRIMARY
CONCERN...BUT SIGNIFICANT DCAPE FROM ANTECEDENT DRY AIR ABOVE 750
HPA MAY BE ENOUGH TO OVERCOME ANY LOW-LEVEL STABILITY TO PRODUCE
STRONG SFC WINDS. THE CHANCE IS QUITE CONDITIONAL UPON THE TIMELY
ALIGNMENT OF THE DEEP FORCING AND THE SFC FRONT. 00Z GUIDANCE HAS
SLOWED THE SFC FRONT SLIGHTLY...LEADING TO SLIGHTLY BETTER CHANCE
FOR STRONGER STORMS. SHOWERS AND STORMS WILL LINGER INTO THE
AFTERNOON FOR MUCH OF THE SOUTHEAST HALF AS THE DEEP FORCING IS SLOW
TO EXIT. SOME DEEP-LAYER DRYING AND LOW-LEVEL FRONTOLYSIS WILL END
MOST OF THE PRECIP BY LATE AFTERNOON. HAVE THUS REMOVED POPS FOR
MONDAY NIGHT.
TUESDAY...MOST OF THE DAY WILL BE DRY AND PARTLY CLOUDY. THE LOW-
LEVEL FRONT FROM SUN NIGHT AND MON WILL HAVE STALLED ACROSS WI AND
LOWER MI BY TUESDAY MORNING...BUT WILL BEGIN TO SURGE NORTHWARD LATE
TUESDAY IN RESPONSE TO A SFC LOW FORMING AHEAD OF DEEP TROUGH ACROSS
THE NORTHERN AND CENTRAL PLAINS. DRY AIR SHOULD LIMIT PRECIP
CHANCES...BUT WILL KEEP A SLIGHT CHANCE ALONG THE WI BORDER FOR THE
AFTERNOON.
TUESDAY NIGHT THROUGH FRIDAY...DEEP TROUGHING DEVELOPING OVER THE
NORTHERN ROCKIES EARLY NEXT WEEK WILL INDUCE A SFC LOW ACROSS THE
NORTHERN PLAINS LATE TUESDAY. MODEL GUIDANCE IS COMING INTO BETTER
AGREEMENT WITH THIS SYSTEM...SO CONFIDENCE IS ON THE RISE FOR THE
FORECAST DURING THE MIDDLE OF THE WEEK. WAA PRECIP SHOULD SPREAD
ACROSS THE CWA FROM SW TO NE TUESDAY NIGHT. THEN...A PROLONGED
PERIOD WITH LOW-LEVEL FGEN...MID-LEVEL Q-VECTOR CONV...AND A SERIES
OF JET STREAKS...WILL BRING RAIN ACROSS MOST OF THE CWA WED AND WED
NIGHT. WITH MODEL AGREEMENT GROWING...HAVE ADDED SOME LIKELY POPS
INTO THE FORECAST FOR WED.
DEEP MOISTURE WILL EXIT WED NIGHT INTO THURSDAY...BUT LINGERING LOW-
LEVEL MOISTURE WILL CONTINUE TO WRAP AROUND THE DEPARTING SYSTEM.
SOME SHOWERS AND/OR DRIZZLE SHOULD CONTINUE ACROSS MAINLY THE
NORTHERN CWA...ESPECIALLY FOR UPSLOPE REGIONS ALONG LAKE SUPERIOR.
PRECIP SHOULD END ACROSS THE ENTIRE CWA BY FRIDAY MORNING AS SFC AND
MID-LEVEL RIDGING BUILD ACROSS THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 116 PM EDT SAT AUG 15 2015
VFR CONDITIONS WILL PREDOMINATE THROUGH THE FCST PERIOD.
STRENGTHENING SW FLOW TONIGHT MAY RESULT IN LLWS CONDITIONS
AT ALL TAF SITES WHICH WILL LAST INTO SUN MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 456 AM EDT SAT AUG 15 2015
FOG WILL REMAIN POSSIBLE OVER EASTERN TODAY AS HIGH PRESSURE BUILDS
INTO THE UPPER GREAT LAKES. THE HIGH WILL DRIFT INTO THE MID
ATLANTIC STATES THROUGH THE WEEKEND. DURING THIS TIME...A LOW WILL
MOVE FROM S SASKATCHEWAN ACROSS NW ONTARIO...AND TO JAMES BAY LATE
ON SUNDAY WHILE DEEPENING. THIS LOW WILL CONTINUE INTO QUEBEC ON
MONDAY AND DRAG A COLD FRONT ACROSS THE UPPER LAKES SUNDAY NIGHT.
WINDS THROUGH THE PERIOD WILL GENERALLY REMAIN LESS THAN 25
KTS...HOWEVER SW WINDS AHEAD OF THE COLD FRONT SUNDAY MAY GUST NEAR
30 KTS AT THE HIGHER OBSERVATION PLATFORMS. HIGH PRESSURE OVER
CENTRAL CANADA AND THE NORTHERN PLAINS ON MONDAY MORNING WILL CROSS
THE UPPER GREAT LAKES AND NORTHERN ONTARIO THROUGH EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...07
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
111 PM EDT SAT AUG 15 2015
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 321 AM EDT SAT AUG 15 2015
SUMMER WEATHER WILL PREVAIL THROUGH THIS WEEKEND WITH HIGHS INLAND
OF LAKE MICHIGAN NEAR 90 ON BOTH TODAY AND SUNDAY AND OVERNIGHT
LOWS WILL MOSTLY BE FROM THE MID 60S TO LOWER 70S. ALL OF THIS IS
DUE TO A LARGE SURFACE HIGH THAT BY SUNDAY WILL BE CENTERED OVER
THE SOUTHEASTERN UNITED STATES. MEANWHILE... A STRONG CANADIAN
STORM WILL TRACK EAST THROUGH CENTRAL CANADA TRAILING A COLD FRONT
BEHIND IT. THAT FRONT WILL REACH CENTRAL LOWER MICHIGAN MONDAY AND
STALL THERE. THAT WILL BRING SCATTERED THUNDERSTORMS TO THE
REGION. A STRONG...FALL LIKE STORM WILL DEVELOP OVER THE WESTERN
HIGH PLAINS ON MONDAY AND THAT WILL TRACK ALONG THE FRONT TOWARD
MICHIGAN. THIS FALL LIKE STORM SYSTEM WILL BRING THE THREAT OF
STRONG THUNDERSTORMS WEDNESDAY THEN MUCH COOLER AND BREEZY WEATHER
ON THURSDAY BEHIND THE SYSTEMS STRONG COLD FRONT.
&&
.UPDATE...
ISSUED AT 709 AM EDT SAT AUG 15 2015
I HAVE ADDED LAKE BREEZE CONVERGENCE THUNDERSTORMS TO THE
AFTERNOON FORECAST AND DECREASED THE CONVECTION NEAR AND SOUTH OF
I-94 THIS AFTERNOON. SEVERAL RUNS OF THE HRRR CONTINUE TO SHOW
CONVECTION DEVELOPING BETWEEN US-131 AND US-31 EARLY TO MID
AFTERNOON ON THE LAKE BREEZE CONVERGENCE BOUNDARY. THE NAM IS
SHOWING 2000 TO 25000 J/KG OF MOST UNSTABLE CAPE IN THAT AREA THIS
AFTERNOON. WHILE THERE IS A LOT OF VERY DRY AIR ABOVE 800 MB... WE
COULD STILL SEE A FEW ISOLATED STORMS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 321 AM EDT SAT AUG 15 2015
FOR THE MOST PART EXPECT MID SUMMER LIKE HEAT AND HUMIDITY THROUGH
SUNDAY. A FRONTAL SYSTEM STALLING OVER CENTRAL LOWER MICHIGAN
MONDAY WILL BRING THE PROSPECT OF THUNDERSTORMS BACK INTO THE
PICTURE.
A LARGE RIDGE WILL CREST OVER MICHIGAN TONIGHT AND SOUTHWEST
LOWER MICHIGAN WILL BE DIRECTLY UNDER THE AXIS OF THE RIDGE THIS
EVENING. WITH THE BUILDING RIDGE OVERHEAD THAT MEANS A LOT OF WARM
AIR AT MID AND HIGH LEVELS DUE TO THE ASSOCIATED SUBSIDENCE. THAT
ALSO MEANS A LOT OF VERY DRY AIR AT MID AND HIGH LEVELS. THAT SORT
OF SET UP WILL KEEP DRY WEATHER OVER MOST OF THE AREA THROUGH
SUNDAY.
THERE IS JUST ONE LITTLE GLITCH TO WATCH TODAY. THE SAME SYSTEM
THAT BROUGHT THE CONVECTION FRIDAY AFTERNOON INTO EARLY THIS
MORNING STALLS OVER OHIO/INDIANA TODAY. THAT PUTS THE DEFORMATION
ZONE OF THAT SYSTEM OVER OUR SOUTHERN CWA (NEAR AND SOUTH OF
I-94). IN THIS AREA THERE WILL BE LESS SUBSIDENCE SO SOME
CONVECTION IS POSSIBLE. I PUT LOW CHANCE POPS IN THAT AREA AS A
RESULT OF THIS CONSIDERATION.
THE FRONT TRAILING THE CANADIAN STORM SYSTEM REACHES LOWER
MICHIGAN MONDAY THEN STALLS. WHILE THERE IS LITTLE IN THE WAY OF
MID LEVEL DYNAMICS...THERE IS INSTABILITY AND SURFACE CONVERGENCE
WITH THE FRONT SO I HAVE CHANCE POPS FOR MONDAY TO COVER THE
POTENTIAL FOR SCATTERED AFTERNOON THUNDERSTORMS.
I USED THE 1000/925 MB THICKNESS TOOL TO COME UP WITH THE HIGH
TEMPERATURES SATURDAY THROUGH MONDAY. HIGHS WILL BE CLOSE TO 90
INLAND BOTH DAYS... ONLY THE MID 80S MONDAY DUE TO MORE CLOUDS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 AM EDT SAT AUG 15 2015
A CONSENSUS OF LATEST 00Z MEDIUM RANGE GUIDANCE CONTINUES TO
INDICATE POTENTIAL FOR A STRENGTHENING LOW PRESSURE SYSTEM TO BRING
A GOOD CHANCE OF THUNDERSTORMS FOR MIDWEEK WITH AN ELEVATED RISK
FOR STRONG TO POTENTIALLY SEVERE WX AT THAT TIME.
THERE WILL BE A CONTINUED SPOTTER ACTIVATION IS POSSIBLE
WEDNESDAY. FOR SCATTERED SHOWERS AND STORMS MONDAY NIGHT THROUGH
TUESDAY NIGHT IN A VERY WARM AND HUMID AND SOMEWHAT UNSTABLE
AIRMASS. HOWEVER THE BEST CHANCE FOR STORMS WILL NOT COME UNTIL
WEDNESDAY THROUGH WEDNESDAY NIGHT AS THE STRENGTHENING LOW
PRESSURE SYSTEM AND COLD FRONT MOVES THROUGH OUR REGION.
A MUCH COOLER AND DRIER AIRMASS WILL ADVECT IN BEHIND THAT SYSTEM
FOR VERY LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 107 PM EDT SAT AUG 15 2015
THE COMBINATION OF AN UNSTABLE AIRMASS AND A LAKE BREEZE COULD
LEAD TO A FEW THUNDERSTORMS THIS AFTERNOON. RIGHT NOW IT LOOKS
LIKE THE KGRR TAF SITES STANDS THE HIGHEST PROBABILITY FOR THIS TO
HAPPEN. SO I DO FEATURE A VCTS IN THE FORECAST FOR THIS AFTERNOON.
VFR WEATHER SHOULD PREVAIL AS WE GO INTO THE EVENING. FOR WILL
LIKELY REDEVELOP ONCE AGAIN AND HAS BEEN ADDED TO THE FORECAST FOR
LATE TONIGHT. THE FOG WILL DISSIPATE BY NOON ON SUNDAY.
&&
.MARINE...
ISSUED AT 321 AM EDT SAT AUG 15 2015
THE SYSTEM ON WEDNESDAY WILL SURELY BRING STRONGER WINDS AND
SIGNIFICANT WAVES...THAT WILL HAVE TO BE WATCHED. OTHERWISE GREAT
BEACH WEATHER THROUGH THE WEEKEND. THERE IS THE RISK OF
THUNDERSTORMS MONDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 626 AM EDT SAT AUG 15 2015
FRIDAY THUNDERSTORMS PRODUCED LOCALLY HEAVY RAINFALL IN EXCESS OF
2 OR 3 INCHES IN A FEW RURAL LOCATIONS. AREAL FLOODING HAS BEEN
LIMITED AND RIVER GAUGES ARE REMAINING BELOW BANKFULL. FLOODING IS
NOT EXPECTED FROM SCATTERED SHOWERS/STORMS SATURDAY AFTERNOON.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...LAURENS
AVIATION...MJS
HYDROLOGY...CAS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
752 AM EDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 456 AM EDT SAT AUG 15 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO
THE UPPER MS VALLEY RESULTING IN NRLY MID/UPPER LEVEL FLOW THROUGH
THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDED FROM QUEBEC
THROUGH THE NRN LAKES INTO THE CNTRL PLAINS. ALTHOUGH MAINLY CLEAR
SKIES PREVAILED ACROSS UPPER MI...FAVORABLE RADIATIONAL COOLING HAS
ALLOWED PATCHY SHALLOW FOG TO DEVELOP.
TODAY...WITH THE RIDGE AND STRONG CAPPING OVER THE AREA...DRY
WEATHER IS EXPECTED. MIXING TO NEAR 850 MB TEMPS THAT CLIMB TO
AROUND 20C SUPPORTS TEMPS NEAR 90 OVER THE WEST HALF OF THE CWA.
LIGHT SRLY FLOW WILL KEEP TEMPS CLOSER TO 80 NEAR LAKE MI. OVER THE
NORTH...LAKE BREEZES DURING THE AFTERNOON WILL BRING LIMITED RELIEF
WITH TEMPS STILL INTO THE LOWER TO MID 80S NEAR LAKE SUPERIOR.
TONIGHT...WARM AND MORE HUMID CONDITIONS WILL PREVAIL AS INCREASING
SW WINDS DRAW MORE MOISTURE INTO THE REGION. BOUNDARY LAYER WINDS TO
AROUND 20 KNOTS AND ASSOCIATED MIXING WILL KEEP TEMPS MAINLY IN THE
60S...EXCEPT LOWER 70S FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 421 AM EDT SAT AUG 15 2015
SUNDAY...ONE LAST WARM AND HUMID DAY IS IN STORE BEFORE SEASONABLY
COOL CONDITIONS TAKE OVER FOR THE WORK WEEK. 850 HPA TEMPS NEARING
20C COMBINED WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES WILL RESULT IN
TEMPS WELL INTO THE 80S AND LOW 90S ACROSS THE CWA. DECENT SW
GRADIENT FLOW WILL KEEP THE LAKE SUPERIOR LAKE BREEZE
OFFSHORE...RESULTING IN SW DOWNSLOPE LOCATIONS POTENTIALLY REACHING
THE LOW 90S. AN APPROACHING SFC COLD FRONT ASSOCIATED WITH A SFC LOW
TRACKING ACROSS NORTHERN ONTARIO WILL BE NEARING THE WESTERN CWA
DURING THE AFTERNOON. SOME MODEL GUIDANCE IS INDICATING A FEW
SHOWERS AND STORMS MAY DEVELOP ACROSS THE FAR WEST LATE IN THE
AFTERNOON...BUT CAPPING BETWEEN 750 AND 850 HPA ALONG WITH MINIMAL
FORCING SHOULD EITHER INHIBIT PRECIP DEVELOPMENT...OR DESTROY ANY
APPROACHING PRECIP.
SUNDAY NIGHT THROUGH MONDAY NIGHT...THE SFC COLD FRONT WILL BE
NEARING OR ENTERING WESTERN UPPER MI AT 00Z MONDAY. AS SUNDAY NIGHT
PROGRESSES...AN ACTIVE RIGHT ENTRANCE TO A 120KT UPPER JET WILL
ALIGN WITH A QUICK-MOVING SHORTWAVE FROM THE NORTHERN PLAINS TO
PRODUCE A SHORT...BUT POTENT STRIP OF FORCING ACROSS THE WEST AND
CENTRAL CWA. MUCAPE APPROACHING 1000 J/KG AND 0-6KM SHEAR OF 30 TO
40 KTS SUPPORT A CHANCE OF STRONG STORMS ACROSS THE WEST IN THE
EVENING AS THIS FORCING INCREASES. LARGE HAIL IS THE PRIMARY
CONCERN...BUT SIGNIFICANT DCAPE FROM ANTECEDENT DRY AIR ABOVE 750
HPA MAY BE ENOUGH TO OVERCOME ANY LOW-LEVEL STABILITY TO PRODUCE
STRONG SFC WINDS. THE CHANCE IS QUITE CONDITIONAL UPON THE TIMELY
ALIGNMENT OF THE DEEP FORCING AND THE SFC FRONT. 00Z GUIDANCE HAS
SLOWED THE SFC FRONT SLIGHTLY...LEADING TO SLIGHTLY BETTER CHANCE
FOR STRONGER STORMS. SHOWERS AND STORMS WILL LINGER INTO THE
AFTERNOON FOR MUCH OF THE SOUTHEAST HALF AS THE DEEP FORCING IS SLOW
TO EXIT. SOME DEEP-LAYER DRYING AND LOW-LEVEL FRONTOLYSIS WILL END
MOST OF THE PRECIP BY LATE AFTERNOON. HAVE THUS REMOVED POPS FOR
MONDAY NIGHT.
TUESDAY...MOST OF THE DAY WILL BE DRY AND PARTLY CLOUDY. THE LOW-
LEVEL FRONT FROM SUN NIGHT AND MON WILL HAVE STALLED ACROSS WI AND
LOWER MI BY TUESDAY MORNING...BUT WILL BEGIN TO SURGE NORTHWARD LATE
TUESDAY IN RESPONSE TO A SFC LOW FORMING AHEAD OF DEEP TROUGH ACROSS
THE NORTHERN AND CENTRAL PLAINS. DRY AIR SHOULD LIMIT PRECIP
CHANCES...BUT WILL KEEP A SLIGHT CHANCE ALONG THE WI BORDER FOR THE
AFTERNOON.
TUESDAY NIGHT THROUGH FRIDAY...DEEP TROUGHING DEVELOPING OVER THE
NORTHERN ROCKIES EARLY NEXT WEEK WILL INDUCE A SFC LOW ACROSS THE
NORTHERN PLAINS LATE TUESDAY. MODEL GUIDANCE IS COMING INTO BETTER
AGREEMENT WITH THIS SYSTEM...SO CONFIDENCE IS ON THE RISE FOR THE
FORECAST DURING THE MIDDLE OF THE WEEK. WAA PRECIP SHOULD SPREAD
ACROSS THE CWA FROM SW TO NE TUESDAY NIGHT. THEN...A PROLONGED
PERIOD WITH LOW-LEVEL FGEN...MID-LEVEL Q-VECTOR CONV...AND A SERIES
OF JET STREAKS...WILL BRING RAIN ACROSS MOST OF THE CWA WED AND WED
NIGHT. WITH MODEL AGREEMENT GROWING...HAVE ADDED SOME LIKELY POPS
INTO THE FORECAST FOR WED.
DEEP MOISTURE WILL EXIT WED NIGHT INTO THURSDAY...BUT LINGERING LOW-
LEVEL MOISTURE WILL CONTINUE TO WRAP AROUND THE DEPARTING SYSTEM.
SOME SHOWERS AND/OR DRIZZLE SHOULD CONTINUE ACROSS MAINLY THE
NORTHERN CWA...ESPECIALLY FOR UPSLOPE REGIONS ALONG LAKE SUPERIOR.
PRECIP SHOULD END ACROSS THE ENTIRE CWA BY FRIDAY MORNING AS SFC AND
MID-LEVEL RIDGING BUILD ACROSS THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 752 AM EDT SAT AUG 15 2015
VFR CONDITIONS WILL PREDOMINATE THROUGH THE FCST PERIOD.
STRENGTHENING SW FLOW TONIGHT MAY RESULT IN CONDITIONS APPROACHING
LLWS CRITERA TOWARD THE END OF THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 456 AM EDT SAT AUG 15 2015
FOG WILL REMAIN POSSIBLE OVER EASTERN TODAY AS HIGH PRESSURE BUILDS
INTO THE UPPER GREAT LAKES. THE HIGH WILL DRIFT INTO THE MID
ATLANTIC STATES THROUGH THE WEEKEND. DURING THIS TIME...A LOW WILL
MOVE FROM S SASKATCHEWAN ACROSS NW ONTARIO...AND TO JAMES BAY LATE
ON SUNDAY WHILE DEEPENING. THIS LOW WILL CONTINUE INTO QUEBEC ON
MONDAY AND DRAG A COLD FRONT ACROSS THE UPPER LAKES SUNDAY NIGHT.
WINDS THROUGH THE PERIOD WILL GENERALLY REMAIN LESS THAN 25
KTS...HOWEVER SW WINDS AHEAD OF THE COLD FRONT SUNDAY MAY GUST NEAR
30 KTS AT THE HIGHER OBSERVATION PLATFORMS. HIGH PRESSURE OVER
CENTRAL CANADA AND THE NORTHERN PLAINS ON MONDAY MORNING WILL CROSS
THE UPPER GREAT LAKES AND NORTHERN ONTARIO THROUGH EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
710 AM EDT SAT AUG 15 2015
LATEST UPDATE...
UPDATE/AVIATION
.SYNOPSIS...
ISSUED AT 321 AM EDT SAT AUG 15 2015
SUMMER WEATHER WILL PREVAIL THROUGH THIS WEEKEND WITH HIGHS INLAND
OF LAKE MICHIGAN NEAR 90 ON BOTH TODAY AND SUNDAY AND OVERNIGHT
LOWS WILL MOSTLY BE FROM THE MID 60S TO LOWER 70S. ALL OF THIS IS
DUE TO A LARGE SURFACE HIGH THAT BY SUNDAY WILL BE CENTERED OVER
THE SOUTHEASTERN UNITED STATES. MEANWHILE... A STRONG CANADIAN
STORM WILL TRACK EAST THROUGH CENTRAL CANADA TRAILING A COLD FRONT
BEHIND IT. THAT FRONT WILL REACH CENTRAL LOWER MICHIGAN MONDAY AND
STALL THERE. THAT WILL BRING SCATTERED THUNDERSTORMS TO THE
REGION. A STRONG...FALL LIKE STORM WILL DEVELOP OVER THE WESTERN
HIGH PLAINS ON MONDAY AND THAT WILL TRACK ALONG THE FRONT TOWARD
MICHIGAN. THIS FALL LIKE STORM SYSTEM WILL BRING THE THREAT OF
STRONG THUNDERSTORMS WEDNESDAY THEN MUCH COOLER AND BREEZY WEATHER
ON THURSDAY BEHIND THE SYSTEMS STRONG COLD FRONT.
&&
.UPDATE...
ISSUED AT 709 AM EDT SAT AUG 15 2015
I HAVE ADDED LAKE BREEZE CONVERGENCE THUNDERSTORMS TO THE
AFTERNOON FORECAST AND DECREASED THE CONVECTION NEAR AND SOUTH OF
I-94 THIS AFTERNOON. SEVERAL RUNS OF THE HRRR CONTINUE TO SHOW
CONVECTION DEVELOPING BETWEEN US-131 AND US-31 EARLY TO MID
AFTERNOON ON THE LAKE BREEZE CONVERGENCE BOUNDARY. THE NAM IS
SHOWING 2000 TO 25000 J/KG OF MOST UNSTABLE CAPE IN THAT AREA THIS
AFTERNOON. WHILE THERE IS A LOT OF VERY DRY AIR ABOVE 800 MB... WE
COULD STILL SEE A FEW ISOLATED STORMS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 321 AM EDT SAT AUG 15 2015
FOR THE MOST PART EXPECT MID SUMMER LIKE HEAT AND HUMIDITY THROUGH
SUNDAY. A FRONTAL SYSTEM STALLING OVER CENTRAL LOWER MICHIGAN
MONDAY WILL BRING THE PROSPECT OF THUNDERSTORMS BACK INTO THE
PICTURE.
A LARGE RIDGE WILL CREST OVER MICHIGAN TONIGHT AND SOUTHWEST
LOWER MICHIGAN WILL BE DIRECTLY UNDER THE AXIS OF THE RIDGE THIS
EVENING. WITH THE BUILDING RIDGE OVERHEAD THAT MEANS A LOT OF WARM
AIR AT MID AND HIGH LEVELS DUE TO THE ASSOCIATED SUBSIDENCE. THAT
ALSO MEANS A LOT OF VERY DRY AIR AT MID AND HIGH LEVELS. THAT SORT
OF SET UP WILL KEEP DRY WEATHER OVER MOST OF THE AREA THROUGH
SUNDAY.
THERE IS JUST ONE LITTLE GLITCH TO WATCH TODAY. THE SAME SYSTEM
THAT BROUGHT THE CONVECTION FRIDAY AFTERNOON INTO EARLY THIS
MORNING STALLS OVER OHIO/INDIANA TODAY. THAT PUTS THE DEFORMATION
ZONE OF THAT SYSTEM OVER OUR SOUTHERN CWA (NEAR AND SOUTH OF
I-94). IN THIS AREA THERE WILL BE LESS SUBSIDENCE SO SOME
CONVECTION IS POSSIBLE. I PUT LOW CHANCE POPS IN THAT AREA AS A
RESULT OF THIS CONSIDERATION.
THE FRONT TRAILING THE CANADIAN STORM SYSTEM REACHES LOWER
MICHIGAN MONDAY THEN STALLS. WHILE THERE IS LITTLE IN THE WAY OF
MID LEVEL DYNAMICS...THERE IS INSTABILITY AND SURFACE CONVERGENCE
WITH THE FRONT SO I HAVE CHANCE POPS FOR MONDAY TO COVER THE
POTENTIAL FOR SCATTERED AFTERNOON THUNDERSTORMS.
I USED THE 1000/925 MB THICKNESS TOOL TO COME UP WITH THE HIGH
TEMPERATURES SATURDAY THROUGH MONDAY. HIGHS WILL BE CLOSE TO 90
INLAND BOTH DAYS... ONLY THE MID 80S MONDAY DUE TO MORE CLOUDS.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 321 AM EDT SAT AUG 15 2015
A CONSENSUS OF LATEST 00Z MEDIUM RANGE GUIDANCE CONTINUES TO
INDICATE POTENTIAL FOR A STRENGTHENING LOW PRESSURE SYSTEM TO BRING
A GOOD CHANCE OF THUNDERSTORMS FOR MIDWEEK WITH AN ELEVATED RISK
FOR STRONG TO POTENTIALLY SEVERE WX AT THAT TIME.
THERE WILL BE A CONTINUED SPOTTER ACTIVIATION IS POSSIBLE
WEDNESDAY. FOR SCATTERED SHOWERS AND STORMS MONDAY NIGHT THROUGH
TUESDAY NIGHT IN A VERY WARM AND HUMID AND SOMEWHAT UNSTABLE
AIRMASS. HOWEVER THE BEST CHANCE FOR STORMS WILL NOT COME UNTIL
WEDNESDAY THROUGH WEDNESDAY NIGHT AS THE STRENGTHENING LOW
PRESSURE SYSTEM AND COLD FRONT MOVES THROUGH OUR REGION.
A MUCH COOLER AND DRIER AIRMASS WILL ADVECT IN BEHIND THAT SYSTEM
FOR VERY LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 709 AM EDT SAT AUG 15 2015
FOR THE MOST PART VFR CONDITIONS ARE EXPECTED THROUGH SUNDAY
NIGHT. THERE COULD BE SOME LAKE BREEZE CONVERGENCE BOUNDARY
THUNDERSTORMS AT GRR AND MKG THIS AFTERNOON SO I WILL PUT VCTS IN
THOSE TAF FORECASTS. OTHERWISE LIGHT WINDS AND NO CIGS BELOW 12000
FT AGL THROUGH SUNDAY.
&&
.MARINE...
ISSUED AT 321 AM EDT SAT AUG 15 2015
THE SYSTEM ON WEDNESDAY WILL SURELY BRING STRONGER WINDS AND
SIGNIFICANT WAVES...THAT WILL HAVE TO BE WATCHED. OTHERWISE GREAT
BEACH WEATHER THROUGH THE WEEKEND. THERE IS THE RISK OF
THUNDERSTORMS MONDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 626 AM EDT SAT AUG 15 2015
FRIDAY THUNDERSTORMS PRODUCED LOCALLY HEAVY RAINFALL IN EXCESS OF
2 OR 3 INCHES IN A FEW RURAL LOCATIONS. AREAL FLOODING HAS BEEN
LIMITED AND RIVER GAUGES ARE REMAINING BELOW BANKFULL. FLOODING IS
NOT EXPECTED FROM SCATTERED SHOWERS/STORMS SATURDAY AFTERNOON.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...LAURENS
AVIATION...WDM
HYDROLOGY...CAS
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
458 AM EDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 456 AM EDT SAT AUG 15 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A RIDGE FROM THE SW CONUS INTO
THE UPPER MS VALLEY RESULTING IN NRLY MID/UPPER LEVEL FLOW THROUGH
THE WRN GREAT LAKES. AT THE SFC...A RIDGE EXTENDED FROM QUEBEC
THROUGH THE NRN LAKES INTO THE CNTRL PLAINS. ALTHOUGH MAINLY CLEAR
SKIES PREVAILED ACROSS UPPER MI...FAVORABLE RADIATIONAL COOLING HAS
ALLOWED PATCHY SHALLOW FOG TO DEVELOP.
TODAY...WITH THE RIDGE AND STRONG CAPPING OVER THE AREA...DRY
WEATHER IS EXPECTED. MIXING TO NEAR 850 MB TEMPS THAT CLIMB TO
AROUND 20C SUPPORTS TEMPS NEAR 90 OVER THE WEST HALF OF THE CWA.
LIGHT SRLY FLOW WILL KEEP TEMPS CLOSER TO 80 NEAR LAKE MI. OVER THE
NORTH...LAKE BREEZES DURING THE AFTERNOON WILL BRING LIMITED RELIEF
WITH TEMPS STILL INTO THE LOWER TO MID 80S NEAR LAKE SUPERIOR.
TONIGHT...WARM AND MORE HUMID CONDITIONS WILL PREVAIL AS INCREASING
SW WINDS DRAW MORE MOISTURE INTO THE REGION. BOUNDARY LAYER WINDS TO
AROUND 20 KNOTS AND ASSOCIATED MIXING WILL KEEP TEMPS MAINLY IN THE
60S...EXCEPT LOWER 70S FOR DOWNSLOPING AREAS ALONG LAKE SUPERIOR.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 421 AM EDT SAT AUG 15 2015
SUNDAY...ONE LAST WARM AND HUMID DAY IS IN STORE BEFORE SEASONABLY
COOL CONDITIONS TAKE OVER FOR THE WORK WEEK. 850 HPA TEMPS NEARING
20C COMBINED WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES WILL RESULT IN
TEMPS WELL INTO THE 80S AND LOW 90S ACROSS THE CWA. DECENT SW
GRADIENT FLOW WILL KEEP THE LAKE SUPERIOR LAKE BREEZE
OFFSHORE...RESULTING IN SW DOWNSLOPE LOCATIONS POTENTIALLY REACHING
THE LOW 90S. AN APPROACHING SFC COLD FRONT ASSOCIATED WITH A SFC LOW
TRACKING ACROSS NORTHERN ONTARIO WILL BE NEARING THE WESTERN CWA
DURING THE AFTERNOON. SOME MODEL GUIDANCE IS INDICATING A FEW
SHOWERS AND STORMS MAY DEVELOP ACROSS THE FAR WEST LATE IN THE
AFTERNOON...BUT CAPPING BETWEEN 750 AND 850 HPA ALONG WITH MINIMAL
FORCING SHOULD EITHER INHIBIT PRECIP DEVELOPMENT...OR DESTROY ANY
APPROACHING PRECIP.
SUNDAY NIGHT THROUGH MONDAY NIGHT...THE SFC COLD FRONT WILL BE
NEARING OR ENTERING WESTERN UPPER MI AT 00Z MONDAY. AS SUNDAY NIGHT
PROGRESSES...AN ACTIVE RIGHT ENTRANCE TO A 120KT UPPER JET WILL
ALIGN WITH A QUICK-MOVING SHORTWAVE FROM THE NORTHERN PLAINS TO
PRODUCE A SHORT...BUT POTENT STRIP OF FORCING ACROSS THE WEST AND
CENTRAL CWA. MUCAPE APPROACHING 1000 J/KG AND 0-6KM SHEAR OF 30 TO
40 KTS SUPPORT A CHANCE OF STRONG STORMS ACROSS THE WEST IN THE
EVENING AS THIS FORCING INCREASES. LARGE HAIL IS THE PRIMARY
CONCERN...BUT SIGNIFICANT DCAPE FROM ANTECEDENT DRY AIR ABOVE 750
HPA MAY BE ENOUGH TO OVERCOME ANY LOW-LEVEL STABILITY TO PRODUCE
STRONG SFC WINDS. THE CHANCE IS QUITE CONDITIONAL UPON THE TIMELY
ALIGNMENT OF THE DEEP FORCING AND THE SFC FRONT. 00Z GUIDANCE HAS
SLOWED THE SFC FRONT SLIGHTLY...LEADING TO SLIGHTLY BETTER CHANCE
FOR STRONGER STORMS. SHOWERS AND STORMS WILL LINGER INTO THE
AFTERNOON FOR MUCH OF THE SOUTHEAST HALF AS THE DEEP FORCING IS SLOW
TO EXIT. SOME DEEP-LAYER DRYING AND LOW-LEVEL FRONTOLYSIS WILL END
MOST OF THE PRECIP BY LATE AFTERNOON. HAVE THUS REMOVED POPS FOR
MONDAY NIGHT.
TUESDAY...MOST OF THE DAY WILL BE DRY AND PARTLY CLOUDY. THE LOW-
LEVEL FRONT FROM SUN NIGHT AND MON WILL HAVE STALLED ACROSS WI AND
LOWER MI BY TUESDAY MORNING...BUT WILL BEGIN TO SURGE NORTHWARD LATE
TUESDAY IN RESPONSE TO A SFC LOW FORMING AHEAD OF DEEP TROUGH ACROSS
THE NORTHERN AND CENTRAL PLAINS. DRY AIR SHOULD LIMIT PRECIP
CHANCES...BUT WILL KEEP A SLIGHT CHANCE ALONG THE WI BORDER FOR THE
AFTERNOON.
TUESDAY NIGHT THROUGH FRIDAY...DEEP TROUGHING DEVELOPING OVER THE
NORTHERN ROCKIES EARLY NEXT WEEK WILL INDUCE A SFC LOW ACROSS THE
NORTHERN PLAINS LATE TUESDAY. MODEL GUIDANCE IS COMING INTO BETTER
AGREEMENT WITH THIS SYSTEM...SO CONFIDENCE IS ON THE RISE FOR THE
FORECAST DURING THE MIDDLE OF THE WEEK. WAA PRECIP SHOULD SPREAD
ACROSS THE CWA FROM SW TO NE TUESDAY NIGHT. THEN...A PROLONGED
PERIOD WITH LOW-LEVEL FGEN...MID-LEVEL Q-VECTOR CONV...AND A SERIES
OF JET STREAKS...WILL BRING RAIN ACROSS MOST OF THE CWA WED AND WED
NIGHT. WITH MODEL AGREEMENT GROWING...HAVE ADDED SOME LIKELY POPS
INTO THE FORECAST FOR WED.
DEEP MOISTURE WILL EXIT WED NIGHT INTO THURSDAY...BUT LINGERING LOW-
LEVEL MOISTURE WILL CONTINUE TO WRAP AROUND THE DEPARTING SYSTEM.
SOME SHOWERS AND/OR DRIZZLE SHOULD CONTINUE ACROSS MAINLY THE
NORTHERN CWA...ESPECIALLY FOR UPSLOPE REGIONS ALONG LAKE SUPERIOR.
PRECIP SHOULD END ACROSS THE ENTIRE CWA BY FRIDAY MORNING AS SFC AND
MID-LEVEL RIDGING BUILD ACROSS THE UPPER GREAT LAKES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 129 AM EDT SAT AUG 15 2015
SOME PATCHY FOG WL IMPACT MAINLY SAW OVERNGT...WITH VSBYS POSSIBLY
TO LO END MVFR OR EVEN IFR FOR A TIME. A BIT STRONGER SW WIND AT CMX
AND IWD WL LIMIT THE POTENTIAL FOR PERSISTENT FOG DESPITE LO TEMP/
DEWPT DEPRESSIONS AT TAF ISSUANCE. ANY FOG WL BURN OFF AFTER
SUNRISE...WITH VFR CONDITIONS PREDOMINATING THRU THE REST OF THE
FCST PERIOD. STRENGTHENING SW FLOW TNGT MAY RESULT IN SOME LLWS
TOWARD THE END OF THE TAF PERIOD AT THE TAF SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 456 AM EDT SAT AUG 15 2015
FOG WILL REMAIN POSSIBLE OVER EASTERN TODAY AS HIGH PRESSURE BUILDS
INTO THE UPPER GREAT LAKES. THE HIGH WILL DRIFT INTO THE MID
ATLANTIC STATES THROUGH THE WEEKEND. DURING THIS TIME...A LOW WILL
MOVE FROM S SASKATCHEWAN ACROSS NW ONTARIO...AND TO JAMES BAY LATE
ON SUNDAY WHILE DEEPENING. THIS LOW WILL CONTINUE INTO QUEBEC ON
MONDAY AND DRAG A COLD FRONT ACROSS THE UPPER LAKES SUNDAY NIGHT.
WINDS THROUGH THE PERIOD WILL GENERALLY REMAIN LESS THAN 25
KTS...HOWEVER SW WINDS AHEAD OF THE COLD FRONT SUNDAY MAY GUST NEAR
30 KTS AT THE HIGHER OBSERVATION PLATFORMS. HIGH PRESSURE OVER
CENTRAL CANADA AND THE NORTHERN PLAINS ON MONDAY MORNING WILL CROSS
THE UPPER GREAT LAKES AND NORTHERN ONTARIO THROUGH EARLY NEXT WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
336 PM CDT SAT AUG 15 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 336 PM CDT SAT AUG 15 2015
HIGH PRESSURE WAS EXITING THE AREA WHILE A SFC LOW WAS MOVING
THROUGH SOUTH CENTRAL CANADA. THIS RESULTED IN A SOUTHERLY FLOW OF
HOT AND HUMID AIR. TEMPERATURES HAD RISEN INTO THE UPPER 80S AND
LOWER 90S THIS AFTERNOON. HEAT INDICES WERE MAINLY IN THE UPPER 80S
AND LOWER 90S AS WELL...BUT TWM REACHED 100 AT 234 PM. CIRRUS WAS
FLOWING OVER THE TOP OF MOST OF THE FORECAST AREA WITH SOME CU IN NW
WI.
THE LINE OF THUNDERSTORMS IN EASTERN ND HAS SHOWN GLIMPSES THAT IT
IS FALLING APART. JUICY ATMOSPHERE OVER THE REGION TONIGHT...BUT THE
INSTABILITY WANES AS THE EVENING PROGRESSES...PLUS THERE IS NO UPPER
FORCING AS THE FRONT REACHES NW MN BY 06Z. DELAYED THE ONSET OF
THUNDERSTORMS TO CLOSER TO 06Z. LATEST HRRR RUNS HAVE NO RAIN IN THE
AREA THROUGH 06Z. BY 12Z...MODELS AGREE ON THE FRONT REACHING NE MN.
HOWEVER...MOISTURE IS DIMINISHING FOR ANY STORMS TO FIRE ON. HAVE
TRIED TO BLEND THE HIRES WITH THE DETERMINISTIC MODELS AND
SURROUNDING OFFICES FOR POPS/QPF/WEATHER.
ON SUNDAY...THE FRONT CONTINUES EWD INTO NW WI. HOWEVER...MOISTURE
IS STILL LIMITED. GREATEST MOISTURE SOURCE WILL BE FOUND ALONG THE
SOUTHERN EDGE OF THE REGION WHERE POPS ARE HIGHEST. MODELS DIFFER ON
THE TIMING AND QPF AND USED A BLEND WITH NEIGHBORING OFFICES.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 336 PM CDT SAT AUG 15 2015
SUNDAY NIGHT THE FRONT CONTINUES TO SLOWLY SAG SOUTHEAST ACROSS THE
FORECAST AREA...WITH SOME POTENTIAL FOR SHOWERS AND THUNDERSTORMS
ACROSS MAINLY THE SOUTHEASTERN CWA THAT CONTINUES INTO MONDAY DUE TO
THE SLOW FRONT MOVEMENT. WE ENTER A QUIET PERIOD FOR MONDAY NIGHT
AND EARLY TUESDAY WITH A SURFACE RIDGE IN THE VICINITY AND
SEASONABLE TEMPERATURES.
THE NEXT MAJOR WEATHER MAKER WILL AFFECT THE FORECAST AREA MUCH OF
THE UPCOMING WORK WEEK...WITH AN UPPER LEVEL TROUGH AXIS/LOW MOVING
FROM THE ROCKIES ON MONDAY NIGHT...MOVING ACROSS MINNESOTA
WEDNESDAY...AND OFF TO THE EAST THURSDAY. THERE IS STILL QUITE A
BIT OF UNCERTAINTY IN THE TRACK AND TIMING OF THIS STORM...WITH THE
ECMWF FARTHER SOUTH AND MORE PROGRESSIVE THAN THE GFS. IT STILL
LOOKS LIKE THIS STORM SHOULD BRING A PERIOD OF WET WEATHER AND
COOLER TEMPERATURES TO THE NORTHLAND. FOR NOW HAVE KEPT TO THE
CONSENSUS WITH HIGHS TUESDAY-THURSDAY IN THE MID 60S TO MID 70S WITH
CHANCE TO LIKELY POPS BEGINNING TUESDAY NIGHT AND CONTINUING THROUGH
THURSDAY. FRIDAY AND SATURDAY REMAIN ACTIVE WITH CONTINUING CHANCES
FOR SHOWERS AND THUNDERSTORMS AND HIGHS IN THE 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1245 PM CDT SAT AUG 15 2015
VFR CONDITIONS EXPECTED TODAY AND THROUGH THIS EVENING UNTIL
AT LEAST 05Z TONIGHT. A STRONG COLD FRONT IS EXPECTED TO MOVE
THROUGH THE TERMINALS SUNDAY MORNING. AHEAD OF THIS FRONT STRONG
MID LEVEL WINDS WILL PRODUCE LLWS AFTER THE SURFACE WINDS DIMINISH
AROUND 01Z. A LINE OF THUNDERSTORMS ARE ALSO EXPECTED TO MOVE
TOWARDS THE TERMINALS FROM THE WEST AFTER 05Z TONIGHT...LOWERING
CEILINGS AND VISIBILITIES TO IFR...WITH THE STORMS DIMINISHING AS
THEY MOVE TO THE EAST. VFR CONDITIONS TO RETURN BEHIND THE STORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 68 85 59 74 / 40 20 10 10
INL 67 76 49 69 / 30 10 0 10
BRD 69 82 58 75 / 40 10 10 10
HYR 68 83 60 74 / 0 30 60 20
ASX 69 85 60 73 / 0 10 30 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM...LE
AVIATION...LE
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1228 PM CDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE RAP MODEL SUGGESTS CONVECTION SHOULD DEVELOP JUST WEST OF
VALENTINE AROUND 22Z THIS AFTERNOON. THIS IS CLOSE TO THE TRIPLE
POINT OF A DRYLINE BULGE...A PACIFIC COLD FRONT AND DEEP
MOISTURE. THE BEST GUESS ON CAPE WOULD BE 3500J/KG WHICH ISNT
MUCH RELATIVE TO THE 16C TEMPERATURE AT 700MB. STILL THE RAP AND
OTHER MODELS HAVE BEEN ADVERTISING DESTABLIZATION SOMEWHERE
ACROSS THE NCNTL SANDHILLS FOR SEVERAL MODEL RUNS.
THE TEMPERATURE FORECAST FOLLOWS THE WARMER SOLNS AND STILL USES
THE LESS DEEPLY MIXED MODELS FOR DEW POINTS IN THE UPPER 60S.
THIS PRODUCES HEAT ADVISORY CONDITIONS ACROSS PARTS OF WRN AND
NCNTL NEB.
STORM CHANCES SHOULD COMMENCE AROUND 22Z AND INITIALLY...THE
BUNKER RIGHT MOTION IS VERY WEAK SUGGESTING OUTFLOW DOMINANT
BEHAVIOR. WINDS ALOFT AT 300 MB INCREASE SLIGHTLY EARLY THIS
EVENING AND STORM MOTION SHOULD TAKE OFF TO THE EAST AND
SOUTHEAST. STORMS MAY DEVELOP THROUGHOUT THE PANHANDLE AND MOVE
EAST SOUTHEAST ALL EVENING AND OVERNIGHT. THE NAM MAINTAINS
2500J/KG OF 750MB COMPUTED CAPE ALONG THE PACIFIC COLD WHICH
SUGGESTS STRONG TO LOCALLY SEVERE STORMS MAY CONTINUE THIS
EVENING BEFORE THIS INSTABILITY MOVES EAST OF THE FCST AREA
AROUND 06Z. THUS INITIALLY THE STORM MODE WOULD BE PULSE WITH
LARGE HAIL AND WIND DAMAGE POSSIBLE. LARGE HAIL WOULD BE THE MORE
DOMINANT THREAT TONIGHT. SPC GIVES THE FCST AREA A MARGINAL
SEVERE WEATHER RISK THIS AFTERNOON AND TONIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE COLD FRONT WILL STRETCHED ACROSS THE HEART OF THE CWA TO
START THE DAY. THE FRONT WILL BE SLOWLY DRIFTING TO THE SE DURING
THE DAY. THE FRONT WILL BE THE MAIN FOCUS FOR SHOWERS AND
THUNDERSTORMS...INCREASING IN COVERAGE DURING THE DAY AS WE WARM
UP...ALTHOUGH WITH MOSTLY CLOUDY SKIES TEMPS LIKELY TO TOP OUT IN
THE 80S. MODELS WAVERING ON HOW FAR TO THE NW OF THE FRONT
SHOWERS DEVELOP...THUS LOW CONFIDENCE IN PRECIP IN NW CWA. SUNDAY
NIGHT INTO MONDAY THE FRONT STALLS ACROSS THE AREA. MEANWHILE
FLOW ALOFT WILL BE ZONAL AS THE RIDGE WILL HAVE FLATTEN DUE TO
NORTHERN TROUGH. MODELS BRING A COUPLE OF MID LEVEL WAVES TO
BRING SOME ADDED LIFT TO THE REGION.
SOME CONCERNS FOR SUNDAY INTO MONDAY WILL BE SEVERE WEATHER...AND
VERY HEAVY RAINFALL. MODELS SLOWING STORM MOTION TO 10 TO 15 KTS
AND PWATS REMAIN AT OR ABOVE 1.50 INCHES...AND LOCALLY PUSHING
CLOSE TO 1.75 INCHES.
AN UPPER LEVEL TROUGH DIGS ACROSS THE NORTHERN ROCKIES AND PLAINS
TUESDAY. MODELS GROWING CONFIDENCE THAT THIS WILL GIVE THE FRONT
A PUSH SOUTHWARD...HOWEVER THE MID LEVEL LIFT IS BECOMING
IMPRESSIVE DUE TO THE COLD AIR ASSOCIATED WITH THE TROUGH. 850 MB
TEMPS FALL TO AROUND 10C. AT THE SFC...MOS GUIDANCE HAS FOLLOWED
SUIT WITH HIGHS ONLY IN THE MID 60S TO LOWER 70S. TRENDED COOLER
WITH TEMPS...BUT NOT READY TO JUMP THAT COLD JUST YET. IT IS
STILL AUGUST AND WANT TO SEE MORE CONSISTENCY WITH THE COLD MODEL
DEPICTION.
IN THE WAKE OF THE TROUGH...WEAK RIDGING DEVELOPS AND MODELS HAVE
TRENDED DRIER TO END THE WEEK. ALSO SHOULD SEE TEMPS REBOUND
CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1222 PM CDT SAT AUG 15 2015
VFR CONDITIONS WILL PREVAIL FOR THE MAJORITY OF THE NEXT 24 HOURS
OVER WESTERN AND NORTH CENTRAL NEBRASKA. ONLY CONCERNS ARE THE
GUSTY SOUTH WINDS THAT HAVE DEVELOPED AND WILL CONTINUE THROUGH
THE REMAINDER OF THE DAY...AS WELL AS THE CHANCE FOR THUNDERSTORMS
LATER THIS AFTERNOON AND EVENING. THE THUNDERSTORMS WILL HAVE THE
POTENTIAL TO PRODUCE LOCALLY STRONG AND ERRATIC WIND
GUSTS IN ADDITION TO REDUCED CIGS/VISBYS. HOWEVER AT THIS TIME
THE SPATIAL COVERAGE OF THUNDERSTORM ACTIVITY REMAINS IN
QUESTION...AND MAY REMAIN ISOLATED AT BEST. BEST CHANCES AT KVTN
WILL BE AROUND 00Z- 03Z...AND 03Z TO 07Z AT KLBF. THUNDERSTORM
CHANCES CONTINUE OVERNIGHT...HOWEVER CONFIDENCE IS TOO LOW TO
INCLUDE IN THE TAF AT THIS TIME.
SOUTHERLY WINDS BEGIN TO SWITCH LATE THIS EVENING AND OVERNIGHT
AS A FRONT SLOWLY MOVES ACROSS THE SANDHILLS REGION. WINDS WILL
EVENTUALLY BECOME GUSTY OUT OF THE NORTH BY LATE TOMORROW MORNING
AT KVTN. LIGHTER WINDS EXPECTED AT KLBF AS THE FRONT STALLS OUT
NEARBY.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 7 PM CDT /6 PM MDT/ THIS EVENING FOR
NEZ005>010-025-026-094.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...MARTIN
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
628 AM CDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE RAP MODEL SUGGESTS CONVECTION SHOULD DEVELOP JUST WEST OF
VALENTINE AROUND 22Z THIS AFTERNOON. THIS IS CLOSE TO THE TRIPLE
POINT OF A DRYLINE BULGE...A PACIFIC COLD FRONT AND DEEP
MOISTURE. THE BEST GUESS ON CAPE WOULD BE 3500J/KG WHICH ISNT
MUCH RELATIVE TO THE 16C TEMPERATURE AT 700MB. STILL THE RAP AND
OTHER MODELS HAVE BEEN ADVERTISING DESTABLIZATION SOMEWHERE
ACROSS THE NCNTL SANDHILLS FOR SEVERAL MODEL RUNS.
THE TEMPERATURE FORECAST FOLLOWS THE WARMER SOLNS AND STILL USES
THE LESS DEEPLY MIXED MODELS FOR DEW POINTS IN THE UPPER 60S.
THIS PRODUCES HEAT ADVISORY CONDITIONS ACROSS PARTS OF WRN AND
NCNTL NEB.
STORM CHANCES SHOULD COMMENCE AROUND 22Z AND INITIALLY...THE
BUNKER RIGHT MOTION IS VERY WEAK SUGGESTING OUTFLOW DOMINANT
BEHAVIOR. WINDS ALOFT AT 300 MB INCREASE SLIGHTLY EARLY THIS
EVENING AND STORM MOTION SHOULD TAKE OFF TO THE EAST AND
SOUTHEAST. STORMS MAY DEVELOP THROUGHOUT THE PANHANDLE AND MOVE
EAST SOUTHEAST ALL EVENING AND OVERNIGHT. THE NAM MAINTAINS
2500J/KG OF 750MB COMPUTED CAPE ALONG THE PACIFIC COLD WHICH
SUGGESTS STRONG TO LOCALLY SEVERE STORMS MAY CONTINUE THIS
EVENING BEFORE THIS INSTABILITY MOVES EAST OF THE FCST AREA
AROUND 06Z. THUS INITIALLY THE STORM MODE WOULD BE PULSE WITH
LARGE HAIL AND WIND DAMAGE POSSIBLE. LARGE HAIL WOULD BE THE MORE
DOMINANT THREAT TONIGHT. SPC GIVES THE FCST AREA A MARGINAL
SEVERE WEATHER RISK THIS AFTERNOON AND TONIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE COLD FRONT WILL STRETCHED ACROSS THE HEART OF THE CWA TO
START THE DAY. THE FRONT WILL BE SLOWLY DRIFTING TO THE SE DURING
THE DAY. THE FRONT WILL BE THE MAIN FOCUS FOR SHOWERS AND
THUNDERSTORMS...INCREASING IN COVERAGE DURING THE DAY AS WE WARM
UP...ALTHOUGH WITH MOSTLY CLOUDY SKIES TEMPS LIKELY TO TOP OUT IN
THE 80S. MODELS WAVERING ON HOW FAR TO THE NW OF THE FRONT
SHOWERS DEVELOP...THUS LOW CONFIDENCE IN PRECIP IN NW CWA. SUNDAY
NIGHT INTO MONDAY THE FRONT STALLS ACROSS THE AREA. MEANWHILE
FLOW ALOFT WILL BE ZONAL AS THE RIDGE WILL HAVE FLATTEN DUE TO
NORTHERN TROUGH. MODELS BRING A COUPLE OF MID LEVEL WAVES TO
BRING SOME ADDED LIFT TO THE REGION.
SOME CONCERNS FOR SUNDAY INTO MONDAY WILL BE SEVERE WEATHER...AND
VERY HEAVY RAINFALL. MODELS SLOWING STORM MOTION TO 10 TO 15 KTS
AND PWATS REMAIN AT OR ABOVE 1.50 INCHES...AND LOCALLY PUSHING
CLOSE TO 1.75 INCHES.
AN UPPER LEVEL TROUGH DIGS ACROSS THE NORTHERN ROCKIES AND PLAINS
TUESDAY. MODELS GROWING CONFIDENCE THAT THIS WILL GIVE THE FRONT
A PUSH SOUTHWARD...HOWEVER THE MID LEVEL LIFT IS BECOMING
IMPRESSIVE DUE TO THE COLD AIR ASSOCIATED WITH THE TROUGH. 850 MB
TEMPS FALL TO AROUND 10C. AT THE SFC...MOS GUIDANCE HAS FOLLOWED
SUIT WITH HIGHS ONLY IN THE MID 60S TO LOWER 70S. TRENDED COOLER
WITH TEMPS...BUT NOT READY TO JUMP THAT COLD JUST YET. IT IS
STILL AUGUST AND WANT TO SEE MORE CONSISTENCY WITH THE COLD MODEL
DEPICTION.
IN THE WAKE OF THE TROUGH...WEAK RIDGING DEVELOPS AND MODELS HAVE
TRENDED DRIER TO END THE WEEK. ALSO SHOULD SEE TEMPS REBOUND
CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 628 AM CDT SAT AUG 15 2015
SCATTERED THUNDERSTORMS SHOULD DEVELOP 22Z-24Z THIS AFTERNOON NEAR
KVTN AND MOVE SOUTH TOWARD KLBF-KOGA AROUND 04Z-06Z. AS A PACIFIC
COLD FRONT MOVES THROUGH THE FCST AREA TONIGHT...OTHER SCATTERED
THUNDERSTORMS SHOULD DEVELOP AND MOVE EAST AND SOUTHEAST FROM 06Z
ONWARD.
OTHERWISE...VFR IS EXPECTED TODAY AND TONIGHT.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 7 PM CDT /6 PM
MDT/ THIS EVENING FOR NEZ005>010-025-026-094.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CDC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
351 AM CDT SAT AUG 15 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE RAP MODEL SUGGESTS CONVECTION SHOULD DEVELOP JUST WEST OF
VALENTINE AROUND 22Z THIS AFTERNOON. THIS IS CLOSE TO THE TRIPLE
POINT OF A DRYLINE BULGE...A PACIFIC COLD FRONT AND DEEP
MOISTURE. THE BEST GUESS ON CAPE WOULD BE 3500J/KG WHICH ISNT
MUCH RELATIVE TO THE 16C TEMPERATURE AT 700MB. STILL THE RAP AND
OTHER MODELS HAVE BEEN ADVERTISING DESTABLIZATION SOMEWHERE
ACROSS THE NCNTL SANDHILLS FOR SEVERAL MODEL RUNS.
THE TEMPERATURE FORECAST FOLLOWS THE WARMER SOLNS AND STILL USES
THE LESS DEEPLY MIXED MODELS FOR DEW POINTS IN THE UPPER 60S.
THIS PRODUCES HEAT ADVISORY CONDITIONS ACROSS PARTS OF WRN AND
NCNTL NEB.
STORM CHANCES SHOULD COMMENCE AROUND 22Z AND INITIALLY...THE
BUNKER RIGHT MOTION IS VERY WEAK SUGGESTING OUTFLOW DOMINANT
BEHAVIOR. WINDS ALOFT AT 300 MB INCREASE SLIGHTLY EARLY THIS
EVENING AND STORM MOTION SHOULD TAKE OFF TO THE EAST AND
SOUTHEAST. STORMS MAY DEVELOP THROUGHOUT THE PANHANDLE AND MOVE
EAST SOUTHEAST ALL EVENING AND OVERNIGHT. THE NAM MAINTAINS
2500J/KG OF 750MB COMPUTED CAPE ALONG THE PACIFIC COLD WHICH
SUGGESTS STRONG TO LOCALLY SEVERE STORMS MAY CONTINUE THIS
EVENING BEFORE THIS INSTABILITY MOVES EAST OF THE FCST AREA
AROUND 06Z. THUS INITIALLY THE STORM MODE WOULD BE PULSE WITH
LARGE HAIL AND WIND DAMAGE POSSIBLE. LARGE HAIL WOULD BE THE MORE
DOMINANT THREAT TONIGHT. SPC GIVES THE FCST AREA A MARGINAL
SEVERE WEATHER RISK THIS AFTERNOON AND TONIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 350 AM CDT SAT AUG 15 2015
THE COLD FRONT WILL STRETCHED ACROSS THE HEART OF THE CWA TO
START THE DAY. THE FRONT WILL BE SLOWLY DRIFTING TO THE SE DURING
THE DAY. THE FRONT WILL BE THE MAIN FOCUS FOR SHOWERS AND
THUNDERSTORMS...INCREASING IN COVERAGE DURING THE DAY AS WE WARM
UP...ALTHOUGH WITH MOSTLY CLOUDY SKIES TEMPS LIKELY TO TOP OUT IN
THE 80S. MODELS WAVERING ON HOW FAR TO THE NW OF THE FRONT
SHOWERS DEVELOP...THUS LOW CONFIDENCE IN PRECIP IN NW CWA. SUNDAY
NIGHT INTO MONDAY THE FRONT STALLS ACROSS THE AREA. MEANWHILE
FLOW ALOFT WILL BE ZONAL AS THE RIDGE WILL HAVE FLATTEN DUE TO
NORTHERN TROUGH. MODELS BRING A COUPLE OF MID LEVEL WAVES TO
BRING SOME ADDED LIFT TO THE REGION.
SOME CONCERNS FOR SUNDAY INTO MONDAY WILL BE SEVERE WEATHER...AND
VERY HEAVY RAINFALL. MODELS SLOWING STORM MOTION TO 10 TO 15 KTS
AND PWATS REMAIN AT OR ABOVE 1.50 INCHES...AND LOCALLY PUSHING
CLOSE TO 1.75 INCHES.
AN UPPER LEVEL TROUGH DIGS ACROSS THE NORTHERN ROCKIES AND PLAINS
TUESDAY. MODELS GROWING CONFIDENCE THAT THIS WILL GIVE THE FRONT
A PUSH SOUTHWARD...HOWEVER THE MID LEVEL LIFT IS BECOMING
IMPRESSIVE DUE TO THE COLD AIR ASSOCIATED WITH THE TROUGH. 850 MB
TEMPS FALL TO AROUND 10C. AT THE SFC...MOS GUIDANCE HAS FOLLOWED
SUIT WITH HIGHS ONLY IN THE MID 60S TO LOWER 70S. TRENDED COOLER
WITH TEMPS...BUT NOT READY TO JUMP THAT COLD JUST YET. IT IS
STILL AUGUST AND WANT TO SEE MORE CONSISTENCY WITH THE COLD MODEL
DEPICTION.
IN THE WAKE OF THE TROUGH...WEAK RIDGING DEVELOPS AND MODELS HAVE
TRENDED DRIER TO END THE WEEK. ALSO SHOULD SEE TEMPS REBOUND
CLOSER TO NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1146 PM CDT FRI AUG 14 2015
OVER THE NEXT 24 HOURS EXPECT CLEAR TO MOSTLY CLEAR SKIES AT BOTH
THE KLBF AND KVTN TERMINALS. SOME SCATTERED HIGH CLOUDS MAY PUSH
INTO WESTERN NEBRASKA LATE SATURDAY AFTERNOON AND SATURDAY
EVENING. FOR THE KVTN TERMINAL...THERE IS AN INCREASED RISK FOR
ISOLATED THUNDERSTORMS AFTER 02Z SUNDAY AND WILL HANDLE THIS WITH
A PROB30 GROUP.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY FROM NOON CDT /11 AM MDT/ TODAY TO 7 PM CDT /6 PM
MDT/ THIS EVENING FOR NEZ005>010-025-026-094.
&&
$$
SHORT TERM...CDC
LONG TERM...MASEK
AVIATION...CLB
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
950 AM PDT SAT AUG 15 2015
.SYNOPSIS...A FEW THUNDERSTORMS ARE POSSIBLE TODAY OVER PORTIONS OF
MOHAVE COUNTY AND THE MOUNTAINS OF CLARK COUNTY. OTHERWISE HOT AND
DRY CONDITIONS WILL SETTLE INTO THE AREA FOR AN EXTENDED STAY.
STRONG HIGH PRESSURE WILL REMAIN OVER THE MOJAVE DESERT REGION
THROUGH WEDNESDAY BEFORE GRADUALLY WEAKENING ITS HOLD AND ALLOWING
TEMPERATURES TO RETURN TO NORMAL TOWARD THE END OF NEXT WEEK.
&&
.UPDATE...THE AIR MASS IS BECOMING SOMEWHAT DRIER AND MORE STABLE
TODAY. THERE WILL STILL BE ENOUGH MOISTURE AND INSTABILITY FOR A
CHANCE OF THUNDERSTORMS OVER THE CLARK COUNTY MOUNTAINS AND PORTIONS
OF MOHAVE COUNTY AND MAY FAR EASTERN LINCOLN COUNTY...ESPECIALLY IF
YOU BELIEVE THE 12Z NAM12 OUTPUT. THE GFS AND ECMWF ARE MORE STABLE
OVER CLARK COUNTY. PRECIPITABLE WATER VALUES ARE STILL AROUND OR
JUST OVER AN INCH IN CLARK COUNTY SO WITH SOME HEATING I WOULD THINK
THE MOUNTAINS COULD STILL SEE THUNDERSTORMS TODAY. THEREFORE THE
INHERITED FORECAST LOOKS OKAY AND NO UPDATES ARE PLANNED. -HARRISON-
&&
.PREV DISCUSSION...
300 AM PDT SAT AUG 15 2015
.SHORT TERM...TODAY THROUGH MONDAY.
TODAY IS THE LAST DAY TO EVEN CONSIDER ANY THUNDERSTORM ACTIVITY
WITHIN THE FORECAST AREA THROUGH THE SHORT TERM. MODELS SHOW
MOISTURE DECREASING THROUGH THE DAY ALTHOUGH IT REMAINS AN INCH OR
SLIGHTLY BETTER OVER MOHAVE, EASTERN SAN BERNARDINO AND CLARK
COUNTIES. THE PROBLEM WILL BE A MORE STABLE AIRMASS IN PLACE AS HIGH
PRESSURE ALOFT NUDGES WESTWARD AND TEMPS ALOFT WARM. FORECAST
SOUNDING DATA SHOWS STRONG CAPPING IN PLACE THROUGH MIDDAY AND NEVER
COMPLETELY ERODING AS TEMPS ALOFT WARM. THE ONLY POSSIBLE HELP COULD
COME FROM THUNDERSTORMS OVER SOUTHWEST ARIZONA THAT DECAYED EARLIER
IN THE NIGHT. DEBRIS CLOUDINESS FROM THIS ACTIVITY IS CURRENTLY
REACHING INTO EASTERN SAN BERN, CLARK AND SOUTHERN MOHAVE COUNTIES.
SURFACE OBSERVATIONS AND THE KESX VAD WIND PROFILE SHOW NO
DISCERNIBLE CHANGE AS THESE REMNANT CLOUDS PASSED THROUGH. MODEL
FORECAST DATA SHOWS NO OTHER EMBEDDED FEATURE THAT WOULD PROVIDE A
LIFTING MECHANISM SO DAYTIME HEATING WILL BE THE PRIMARY PROVIDER OF
LIFT TODAY. THE HRRR AND NAM12 SHOW LIGHT QPF DEVELOPING FROM CELLS
THIS AFTERNOON IN MOHAVE COUNTY AND THE CLARK COUNTY MOUNTAINS SO
LEFT A SLIGHT CHANCE MENTION OF STORMS IN THESE AREAS. UNLESS I`M
MISSING SOME MICROSCALE FEATURE OR MI-NUTE DETAIL IN THE MODEL DATA,
MY GUESS IS THUNDERSTORM CHANCES IN LAS VEGAS ARE SLIM TO NONE
THROUGH MONDAY.
FORECAST CONCERN NOW SHIFTS TO IMPACTS FROM HEAT AS HIGH PRESSURE
BECOMES THE DOMINANT FEATURE THROUGH THE SHORT TERM. NORMAL HIGH
TEMPERATURES IN LAS VEGAS ARE 102 DEGREES OVER THE WEEKEND SO THE
FORECAST CALLS FOR TEMPERATURES THAT ARE 6-8 DEGREES ABOVE NORMAL
EACH AFTERNOON THROUGH MONDAY. IT IS MORE THAN LIKELY TODAY`S HIGH
TEMPERATURE WILL BE HELD DOWN SOMEWHAT BY THE AMOUNT OF LINGERING
MOISTURE HANGING AROUND THE AREA BUT THIS WILL JUST MAKE IT FEEL ON
THE MUGGY SIDE. AN EXCESSIVE HEAT WARNING REMAINS IN EFFECT FOR
SUNDAY AND MONDAY WHEN HIGH TEMPERATURES WILL BE WARMING TO NEAR
RECORD LEVELS IN MANY DESERT AREAS AND IN SOME ISOLATED CASES...MAY
BREAK RECORDS. NO RECORD HIGH TEMPS ARE CURRENTLY FORECAST FOR LAS
VEGAS BUT AREAS ALONG THE COLORADO RIVER VALLEY COULD SEE HIGHS 114-
118 DEGREES WHILE DEATH VALLEY COULD SEE HIGHS APPROACHING 125
DEGREES. IF PLANNING OUTDOOR ACTIVITY THIS WEEKEND, REMEMBER TO TAKE
NECESSARY PRECAUTIONS TO DEAL WITH THESE VERY HOT CONDITIONS AND
KEEP IN MIND THE SYMPTOMS AND NECESSARY ACTIONS NEEDED TO DEAL WITH
ANY HEAT-RELATED ILLNESSES.
.LONG TERM...TUESDAY THROUGH FRIDAY.
THE 00Z MEDIUM RANGE MODELS NOW INDICATE WE WILL NOT COOL DOWN QUITE
AS FAST AS WAS INDICATED THE PAST SEVERAL RUNS. THIS IS DUE TO
KEEPING A GULF OF ALASKA TROUGH FURTHER INLAND AS IT TRACKS DOWN
OVER BRITISH COLUMBIA AND DROPS ACROSS MONTANA AND WYOMING EARLY
TUESDAY. THIS TRACK WILL HAVE LITTLE INFLUENCE ON OUR REGION AND
WILL ALLOW THE STRONG CLOSED HIGH TO REMAIN OVER SOUTHERN CALIFORNIA
AND THE DESERT SOUTHWEST TUESDAY AND WEDNESDAY. A BROADER TROUGH IS
THEN FORECAST TO WORK ITS WAY DOWN FROM THE NORTHWEST AND GRADUALLY
BREAK DOWN THE RIDGE THURSDAY AND FRIDAY. THIS PATTERN WILL KEEP A
GENERALLY DRY WEST TO NORTHWEST FLOW OVER THE REGION THROUGH THE
WEEK AND HIGH TEMPS WILL REMAIN SOMEWHAT ELEVATED TUESDAY AND
WEDNESDAY FOLLOWED BY A SLIGHT DOWNWARD TREND BACK TO NORMAL THE
LATTER HALF OF THE WEEK.
&&
.AVIATION...FOR MCCARRAN...ISOLATED STORMS ARE POSSIBLE OVER THE
MOUNTAINS TODAY OTHERWISE...DRY CONDITIONS AND TYPICAL DIURNAL WINDS
ARE EXPECTED THROUGH MONDAY
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...TYPICAL DIURNAL SURFACE WINDS ARE EXPECTED IN MOST
AREAS THROUGH THE WEEKEND EXCEPT WHEN ASSOCIATED WITH THUNDERSTORM
OUTFLOW. ISOLATED THUNDERSTORMS ARE POSSIBLE IN MOHAVE COUNTY...
MAINLY THE NORTHERN REGIONS...AND THE CLARK COUNTY MOUNTAINS TODAY
WITH DRY CONDITIONS SUNDAY AND MONDAY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES.
&&
$$
SALMEN/ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS LAS VEGAS NV
300 AM PDT SAT AUG 15 2015
.SYNOPSIS...A FEW THUNDERSTORMS ARE POSSIBLE TODAY OVER PORTIONS OF
MOHAVE COUNTY AND THE MOUNTAINS OF CLARK COUNTY. OTHERWISE HOT AND
DRY CONDITIONS WILL SETTLE INTO THE AREA FOR AN EXTENDED STAY.
STRONG HIGH PRESSURE WILL REMAIN OVER THE MOJAVE DESERT REGION
THROUGH WEDNESDAY BEFORE GRADUALLY WEAKENING ITS HOLD AND ALLOWING
TEMPERATURES TO RETURN TO NORMAL TOWARD THE END OF NEXT WEEK.
&&
.SHORT TERM...TODAY THROUGH MONDAY.
TODAY IS THE LAST DAY TO EVEN CONSIDER ANY THUNDERSTORM ACTIVITY
WITHIN THE FORECAST AREA THROUGH THE SHORT TERM. MODELS SHOW
MOISTURE DECREASING THROUGH THE DAY ALTHOUGH IT REMAINS AN INCH OR
SLIGHTLY BETTER OVER MOHAVE, EASTERN SAN BERNARDINO AND CLARK
COUNTIES. THE PROBLEM WILL BE A MORE STABLE AIRMASS IN PLACE AS HIGH
PRESSURE ALOFT NUDGES WESTWARD AND TEMPS ALOFT WARM. FORECAST
SOUNDING DATA SHOWS STRONG CAPPING IN PLACE THROUGH MIDDAY AND NEVER
COMPLETELY ERODING AS TEMPS ALOFT WARM. THE ONLY POSSIBLE HELP COULD
COME FROM THUNDERSTORMS OVER SOUTHWEST ARIZONA THAT DECAYED EARLIER
IN THE NIGHT. DEBRIS CLOUDINESS FROM THIS ACTIVITY IS CURRENTLY
REACHING INTO EASTERN SAN BERN, CLARK AND SOUTHERN MOHAVE COUNTIES.
SURFACE OBSERVATIONS AND THE KESX VAD WIND PROFILE SHOW NO
DISCERNIBLE CHANGE AS THESE REMNANT CLOUDS PASSED THROUGH. MODEL
FORECAST DATA SHOWS NO OTHER EMBEDDED FEATURE THAT WOULD PROVIDE A
LIFTING MECHANISM SO DAYTIME HEATING WILL BE THE PRIMARY PROVIDER OF
LIFT TODAY. THE HRRR AND NAM12 SHOW LIGHT QPF DEVELOPING FROM CELLS
THIS AFTERNOON IN MOHAVE COUNTY AND THE CLARK COUNTY MOUNTAINS SO
LEFT A SLIGHT CHANCE MENTION OF STORMS IN THESE AREAS. UNLESS I`M
MISSING SOME MICROSCALE FEATURE OR MI-NUTE DETAIL IN THE MODEL DATA,
MY GUESS IS THUNDERSTORM CHANCES IN LAS VEGAS ARE SLIM TO NONE
THROUGH MONDAY.
FORECAST CONCERN NOW SHIFTS TO IMPACTS FROM HEAT AS HIGH PRESSURE
BECOMES THE DOMINANT FEATURE THROUGH THE SHORT TERM. NORMAL HIGH
TEMPERATURES IN LAS VEGAS ARE 102 DEGREES OVER THE WEEKEND SO THE
FORECAST CALLS FOR TEMPERATURES THAT ARE 6-8 DEGREES ABOVE NORMAL
EACH AFTERNOON THROUGH MONDAY. IT IS MORE THAN LIKELY TODAY`S HIGH
TEMPERATURE WILL BE HELD DOWN SOMEWHAT BY THE AMOUNT OF LINGERING
MOISTURE HANGING AROUND THE AREA BUT THIS WILL JUST MAKE IT FEEL ON
THE MUGGY SIDE. AN EXCESSIVE HEAT WARNING REMAINS IN EFFECT FOR
SUNDAY AND MONDAY WHEN HIGH TEMPERATURES WILL BE WARMING TO NEAR
RECORD LEVELS IN MANY DESERT AREAS AND IN SOME ISOLATED CASES...MAY
BREAK RECORDS. NO RECORD HIGH TEMPS ARE CURRENTLY FORECAST FOR LAS
VEGAS BUT AREAS ALONG THE COLORADO RIVER VALLEY COULD SEE HIGHS 114-
118 DEGREES WHILE DEATH VALLEY COULD SEE HIGHS APPROACHING 125
DEGREES. IF PLANNING OUTDOOR ACTIVITY THIS WEEKEND, REMEMBER TO TAKE
NECESSARY PRECAUTIONS TO DEAL WITH THESE VERY HOT CONDITIONS AND
KEEP IN MIND THE SYMPTOMS AND NECESSARY ACTIONS NEEDED TO DEAL WITH
ANY HEAT-RELATED ILLNESSES.
.LONG TERM...TUESDAY THROUGH FRIDAY.
THE 00Z MEDIUM RANGE MODELS NOW INDICATE WE WILL NOT COOL DOWN QUITE
AS FAST AS WAS INDICATED THE PAST SEVERAL RUNS. THIS IS DUE TO
KEEPING A GULF OF ALASKA TROUGH FURTHER INLAND AS IT TRACKS DOWN
OVER BRITISH COLUMBIA AND DROPS ACROSS MONTANA AND WYOMING EARLY
TUESDAY. THIS TRACK WILL HAVE LITTLE INFLUENCE ON OUR REGION AND
WILL ALLOW THE STRONG CLOSED HIGH TO REMAIN OVER SOUTHERN CALIFORNIA
AND THE DESERT SOUTHWEST TUESDAY AND WEDNESDAY. A BROADER TROUGH IS
THEN FORECAST TO WORK ITS WAY DOWN FROM THE NORTHWEST AND GRADUALLY
BREAK DOWN THE RIDGE THURSDAY AND FRIDAY. THIS PATTERN WILL KEEP A
GENERALLY DRY WEST TO NORTHWEST FLOW OVER THE REGION THROUGH THE
WEEK AND HIGH TEMPS WILL REMAIN SOMEWHAT ELEVATED TUESDAY AND
WEDNESDAY FOLLOWED BY A SLIGHT DOWNWARD TREND BACK TO NORMAL THE
LATTER HALF OF THE WEEK.
&&
.AVIATION...FOR MCCARRAN...ISOLATED STORMS ARE POSSIBLE OVER THE
MOUNTAINS TODAY OTHERWISE...DRY CONDITIONS AND TYPICAL DIURNAL WINDS
ARE EXPECTED THROUGH MONDAY
FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...TYPICAL DIURNAL SURFACE WINDS ARE EXPECTED IN MOST
AREAS THROUGH THE WEEKEND EXCEPT WHEN ASSOCIATED WITH THUNDERSTORM
OUTFLOW. ISOLATED THUNDERSTORMS ARE POSSIBLE IN MOHAVE COUNTY...
MAINLY THE NORTHERN REGIONS...AND THE CLARK COUNTY MOUNTAINS TODAY
WITH DRY CONDITIONS SUNDAY AND MONDAY.
&&
.SPOTTER INFORMATION STATEMENT...SPOTTERS ARE ENCOURAGED TO REPORT
ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING
PROCEDURES.
&&
$$
SALMEN/ADAIR
FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:
HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1032 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK TROUGH OF LOW PRESSURE WILL BRING WIDELY SCATTERED SHOWERS
AND THUNDERSTORMS TO PORTIONS OF THE EASTERN GREAT LAKES REGION
TODAY. SUNNY AND HOT WEATHER WILL THEN PREVAIL ON SUNDAY. THE LATE
SUMMER HEAT WILL PERSIST THROUGH THE EARLY PART OF NEXT WEEK WITH
SHOWERS AND THUNDERSTORMS RETURNING AS A SERIES OF DISTURBANCES
CROSS THE NORTHERN UNITED STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY LATE THIS MORNING SHOWS AN AREA OF SHOWERS ACROSS
THE GENESEE VALLEY WEAKENING AS IT SLIDES EASTWARD OUT OF OUR CWA.
OTHERWISE...CLOUDS HAVE STARTED TO BREAK UP WITH THE EXIT OF THIS
FEATURE...ESPECIALLY ON THE LAKE PLAINS WHERE STABLE LAKE SHADOWS
HAVE STARTED TO DEVELOP.
WATER VAPOR IMAGERY AND OBJECTIVE RUC ANALYSIS SHOWING A WEAK/BROAD
TROUGH MOVING SLOWLY SOUTHEAST ACROSS THE LOWER LAKES. THIS FEATURE
WILL CONTINUE TO PROVIDE WEAK LARGE SCALE ASCENT TODAY AS IT MOVES
ACROSS THE AREA. MODEST DAYTIME HEATING WILL ALLOW FOR WEAK
INSTABILITY TO DEVELOP AND FORCE WIDELY SCATTERED SHOWERS AND
STORMS THIS AFTERNOON. DEVELOPING NORTHWEST FLOW BEHIND THE WEAK
TROUGH PASSAGE WILL ALLOW STABLE LAKE SHADOWS TO SPREAD INLAND
ACROSS MOST OF THE LAKE PLAINS...WITH THE GREATER CHANCES FOR
SCATTERED CONVECTION FOCUSING ON THE HIGHER TERRAIN OF THE
SOUTHERN TIER AND FINGER LAKES. THE AIRMASS IS QUITE MOIST...SO
ANY STORM THAT DOES DEVELOP MAY PRODUCE BRIEF HEAVY
DOWNPOURS...BUT CONCENTRATED LONG LASTING HEAVY RAIN IS NOT
EXPECTED.
BEHIND THE PASSAGE OF THE UPPER LEVEL SHORTWAVE THIS EVENING...AND
MUCAPE VALUES DIMINISHED OUR SHOWERS AND THUNDERSTORMS WILL FADE
THROUGH THE EVENING HOURS WITH CLEARING SKIES. DEWPOINTS WILL
CONTINUE TO BE ON THE MUGGY SIDE WITH DEWPOINT TEMPERATURES STILL IN
THE MID 60S. THIS COUPLED WITH ALL THE RECENT RAINS WILL LIKELY
BRING AREAS OF FOG ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
TEMPERATURES TODAY WILL BE A FEW DEGREES ABOVE SEASONAL NORMALS...
WITH TEMPERATURES IN THE LOWER 80S. TONIGHT LOWS WILL DROP BACK INTO
THE LOW TO MID 60S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
DRY WEATHER RETURNS ON SUNDAY AS HIGH PRESSURE SETS UP FROM THE OHIO
VALLEY INTO THE MID ATLANTIC. SUBSIDENCE AND DRYING ASSOCIATED WITH
THE RIDGING WILL PROMOTE MOSTLY SUNNY SKIES WITH SOME DIURNAL
CUMULUS INLAND FROM THE LAKES AND PASSING/THIN CIRRUS. ADDED JUST A
VERY LOW CHANCE POPS ACROSS THE SOUTHERN TIER WHERE A FEW CUMULUS
COULD BECOME MORE DEVELOPED PROVIDING A VERY ISOLATED SPRINKLE OR
LIGHT SHOWER. 850MB TEMPS RISE TO AROUND +18C BY THE END OF THE DAY.
THIS WILL SUPPORT HIGHS IN THE MID TO UPPER 80S ACROSS LOWER
ELEVATIONS INLAND FROM THE LAKES. SOUTHWEST FLOW WILL KEEP AREAS
NORTHEAST OF LAKES ERIE AND ONTARIO JUST A LITTLE COOLER...INCLUDING
METRO BUFFALO AND WATERTOWN. DEW POINTS WILL CLIMB INTO THE MID 60S
MAKING THE SENSIBLE WEATHER JUST A LITTLE MORE UNCOMFORTABLE WHEN
COMBINED WITH THE WARM TEMPERATURES.
THE DRY WEATHER WILL CONTINUE INTO SUNDAY NIGHT AS HIGH PRESSURE
REMAINS IN PLACE FROM THE OHIO VALLEY TO THE MID ATLANTIC. SOUTHWEST
FLOW AROUND THE PERIPHERY OF THE HIGH WILL SUPPORT A WARM AND MUGGY
NIGHT WITH LOWS IN THE LOWER 70S ON THE LAKE PLAINS AIDED BY THE
LIGHT DOWNSLOPE WIND AND MID 60S ACROSS THE INTERIOR SOUTHERN TIER
AND TUG HILL REGION.
MUCH OF MONDAY WILL BE DRY AND WARM...BUT THERE WILL AN INCREASE IN
CLOUD COVER AS THE DAY PROGRESSES. A CLOSED LOW OVER THE LOWER OHIO
VALLEY WILL EJECT A LOBE OF VORTICITY...TIMED JUST RIGHT TO BRING
INCREASING CLOUDS AND A CHANCE OF LATE DAY AND EVENING SHOWERS AND
THUNDERSTORMS. LATE IN THE AFTERNOON...THE HIGHEST CHANCE OF
THUNDERSTORMS WILL BE ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES. BY MONDAY EVENING... THE APPROACHING SHORTWAVE WILL
BRING A BETTER CHANCE OF THUNDERSTORMS ARE MUCH OF THE AREA. HIGH
TEMPERATURES ON MONDAY WILL BE A COPY OF SUNDAY...WITH MID TO UPPER
80S. OVERNIGHT LOWS WILL BE IN THE MID TO UPPER 60S...SO CONDITIONS
WILL REMAIN RATHER MUGGY THROUGH THE NIGHT AS WELL... WHICH WILL
LIKELY HELP TO FUEL SOME NOCTURNAL THUNDERSTORMS.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
BERMUDA RIDGE ALONG THE MID ATLANTIC TO SOUTHEAST COAST AND LOW
PRESSURE TROUGHING ACROSS THE MID CONTINENT WILL MAINTAIN A WARM
AND HUMID SOUTHWESTERLY FLOW ACROSS THE REGION FOR THE REST OF THE
WEEK. A SMALL CUTOFF LOW OVER THE LOWER OHIO RIVER VALLEY WILL
OPEN UP AND BECOME ENTRAINED INTO THE UPPER FLOW ACROSS THE
EASTERN GREAT LAKES AND NORTHEASTERN STATES. THIS WILL BRING BACK
UNSETTLED CONDITIONS WITH CHANCES OF PRECIP ACROSS THE REGION ON
TUESDAY AND WEDNESDAY... AND A BETTER CHANCE OF ORGANIZED
CONVECTION ON THURSDAY AS A COLD FRONT CROSSES THE REGION. GFS
BRINGS A GRAZING SHOT OF COOLER AIR AT THE WEEKEND WHEREAS ECMWF
SAGS THE FRONT ACROSS THE REGION WITHOUT MUCH COOLING. THE WEEK
WILL BE GENERALLY ABOVE AVERAGE WITH HIGHS IN THE 80S...MID TO
UPPER 80S ON WEDNESDAY...AND MUCH MILDER THAN CLIMATOLOGY AT NIGHT
WITH LOWS IN THE LOWER TO MID 60S...EVEN LOW 70S ON WEDNESDAY
NIGHT.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
EXPECT MOSTLY VFR CONDITIONS TODAY...WITH SOME EXCEPTIONS. SOME
PATCHY MVFR CIGS MAY LINGER UNTIL 18Z OR SO SOUTH OF THE LAKES.
ALSO...SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP THIS AFTERNOON BUT THESE WILL BE MAINLY INLAND OF THE TAF
SITES WITH ONLY A LOW CHANCE FOR THESE TO IMPACT TAF LOCATIONS FOR
ANY SIGNIFICANT TIME PERIOD. ANY OF THE STORMS TODAY WILL PRODUCE
LOCAL MVFR/IFR CONDITIONS.
ANY SCATTERED CONVECTION WILL END EARLY THIS EVENING WITH CLEARING
SKIES. THE CLEAR SKIES AND STILL ABUNDANT LOW LEVEL MOISTURE WILL
ALLOW FOR PATCHY FOG TO DEVELOP OVERNIGHT WITH AREAS OF MVFR/IFR
VSBY AFTER 06Z.
OUTLOOK...
SUNDAY AND SUNDAY NIGHT...VFR.
MONDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
HIGH PRESSURE AT THE SURFACE...COMBINED WITH STABLE LOW LEVEL LAPSE
RATES WILL YIELD RELATIVELY FLAT WAVE ACTION ON THE EASTERN TWO
GREAT LAKES THROUGH THE WEEKEND. AFTERNOON WINDS WILL INCREASE
TOWARDS 10 TO 12 KNOTS ON THE LAKES AND RIVERS.
WAVES AND WINDS WILL INCREASE SOME MONDAY WITH THE NEXT WEATHER
SYSTEM...THOUGH CONDITIONS MAY REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK/THOMAS
NEAR TERM...APFFEL/HITCHCOCK/THOMAS
SHORT TERM...CHURCH
LONG TERM...CHURCH/WCH
AVIATION...APFFEL/HITCHCOCK/THOMAS
MARINE...APFFEL/THOMAS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
732 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK TROUGH OF LOW PRESSURE WILL BRING WIDELY SCATTERED SHOWERS
AND THUNDERSTORMS TO PORTIONS OF THE EASTERN GREAT LAKES REGION
TODAY. SUNNY AND HOT WEATHER WILL THEN PREVAIL ON SUNDAY. THE LATE
SUMMER HEAT WILL PERSIST THROUGH THE EARLY PART OF NEXT WEEK WITH
SHOWERS AND THUNDERSTORMS RETURNING AS A SERIES OF DISTURBANCES
CROSS THE NORTHERN UNITED STATES.
&&
.NEAR TERM /THROUGH TONIGHT/...
RADAR IMAGERY THIS MORNING SHOWING AN AREA OF WEAKENING RAIN FROM
WESTERN NY INTO THE GENESEE VALLEY AND WESTERN FINGER LAKES. THE
ONLY ACTIVE CONVECTION LEFT ON THIS LINE IS ACROSS THE WESTERN
SOUTHERN TIER. THE WELL DEFINED BAND OF LOW LEVEL CONVERGENCE WHICH
HELPED TO FOCUS THIS TRAINING LINE OF STORMS OVERNIGHT HAS WEAKENED
CONSIDERABLY AND HAS ALSO MOVED SOUTHEAST OF LAKE ERIE...WHICH
LIKELY PLAYED A ROLE IN PROVIDING ADDITIONAL LOW LEVEL MOISTURE FOR
THE FLASH FLOODS LAST NIGHT. EXPECT THIS LINGERING CONVECTION TO
WEAKEN TO SCATTERED SHOWERS THROUGH THE MID TO LATE MORNING HOURS.
EXTENSIVE CLOUD COVER THROUGH THE MORNING SHOULD GIVE WAY TO A FEW
BREAKS IN THE CLOUDS THIS AFTERNOON...ESPECIALLY ON THE LAKE PLAINS
WHERE STABLE LAKE SHADOWS WILL DEVELOP.
WATER VAPOR IMAGERY AND OBJECTIVE RUC ANALYSIS SHOWING A WEAK/BROAD
TROUGH MOVING SLOWLY SOUTHEAST ACROSS THE LOWER LAKES. THIS FEATURE
WILL CONTINUE TO PROVIDE WEAK LARGE SCALE ASCENT TODAY AS IT MOVES
ACROSS THE AREA. ANY LINGERING MORNING CONVECTION WILL FADE AWAY BY
LATE MORNING. MODEST DAYTIME HEATING WILL ALLOW FOR WEAK INSTABILITY
TO DEVELOP AND FORCE WIDELY SCATTERED SHOWERS AND STORMS THIS
AFTERNOON. DEVELOPING NORTHWEST FLOW BEHIND THE WEAK TROUGH PASSAGE
WILL ALLOW STABLE LAKE SHADOWS TO SPREAD INLAND ACROSS MOST OF THE
LAKE PLAINS...WITH THE GREATER CHANCES FOR SCATTERED CONVECTION
FOCUSING ON THE HIGHER TERRAIN OF THE SOUTHERN TIER AND FINGER
LAKES. THE AIRMASS IS QUITE MOIST...SO ANY STORM THAT DOES DEVELOP
MAY PRODUCE BRIEF HEAVY DOWNPOURS...BUT CONCENTRATED LONG LASTING
HEAVY RAIN IS NOT EXPECTED.
BEHIND THE PASSAGE OF THE UPPER LEVEL SHORTWAVE THIS EVENING...AND
MUCAPE VALUES DIMINISHED OUR SHOWERS AND THUNDERSTORMS WILL FADE
THROUGH THE EVENING HOURS WITH CLEARING SKIES. DEWPOINTS WILL
CONTINUE TO BE ON THE MUGGY SIDE WITH DEWPOINT TEMPERATURES STILL IN
THE MID 60S. THIS COUPLED WITH ALL THE RECENT RAINS WILL LIKELY
BRING AREAS OF FOG ACROSS THE REGION LATE TONIGHT AND EARLY SUNDAY.
TEMPERATURES TODAY WILL BE A FEW DEGREES ABOVE SEASONAL NORMALS...
WITH TEMPERATURES IN THE LOWER 80S. TONIGHT LOWS WILL DROP BACK INTO
THE LOW TO MID 60S.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
DRY WEATHER RETURNS ON SUNDAY AS HIGH PRESSURE SETS UP FROM THE OHIO
VALLEY INTO THE MID ATLANTIC. SUBSIDENCE AND DRYING ASSOCIATED WITH
THE RIDGING WILL PROMOTE MOSTLY SUNNY SKIES WITH SOME DIURNAL
CUMULUS INLAND FROM THE LAKES AND PASSING/THIN CIRRUS. ADDED JUST A
VERY LOW CHANCE POPS ACROSS THE SOUTHERN TIER WHERE A FEW CUMULUS
COULD BECOME MORE DEVELOPED PROVIDING A VERY ISOLATED SPRINKLE OR
LIGHT SHOWER. 850MB TEMPS RISE TO AROUND +18C BY THE END OF THE DAY.
THIS WILL SUPPORT HIGHS IN THE MID TO UPPER 80S ACROSS LOWER
ELEVATIONS INLAND FROM THE LAKES. SOUTHWEST FLOW WILL KEEP AREAS
NORTHEAST OF LAKES ERIE AND ONTARIO JUST A LITTLE COOLER...INCLUDING
METRO BUFFALO AND WATERTOWN. DEW POINTS WILL CLIMB INTO THE MID 60S
MAKING THE SENSIBLE WEATHER JUST A LITTLE MORE UNCOMFORTABLE WHEN
COMBINED WITH THE WARM TEMPERATURES.
THE DRY WEATHER WILL CONTINUE INTO SUNDAY NIGHT AS HIGH PRESSURE
REMAINS IN PLACE FROM THE OHIO VALLEY TO THE MID ATLANTIC. SOUTHWEST
FLOW AROUND THE PERIPHERY OF THE HIGH WILL SUPPORT A WARM AND MUGGY
NIGHT WITH LOWS IN THE LOWER 70S ON THE LAKE PLAINS AIDED BY THE
LIGHT DOWNSLOPE WIND AND MID 60S ACROSS THE INTERIOR SOUTHERN TIER
AND TUG HILL REGION.
MUCH OF MONDAY WILL BE DRY AND WARM...BUT THERE WILL AN INCREASE IN
CLOUD COVER AS THE DAY PROGRESSES. A CLOSED LOW OVER THE LOWER OHIO
VALLEY WILL EJECT A LOBE OF VORTICITY...TIMED JUST RIGHT TO BRING
INCREASING CLOUDS AND A CHANCE OF LATE DAY AND EVENING SHOWERS AND
THUNDERSTORMS. LATE IN THE AFTERNOON...THE HIGHEST CHANCE OF
THUNDERSTORMS WILL BE ALONG AND INLAND FROM THE LAKE BREEZE
BOUNDARIES. BY MONDAY EVENING... THE APPROACHING SHORTWAVE WILL
BRING A BETTER CHANCE OF THUNDERSTORMS ARE MUCH OF THE AREA. HIGH
TEMPERATURES ON MONDAY WILL BE A COPY OF SUNDAY...WITH MID TO UPPER
80S. OVERNIGHT LOWS WILL BE IN THE MID TO UPPER 60S...SO CONDITIONS
WILL REMAIN RATHER MUGGY THROUGH THE NIGHT AS WELL... WHICH WILL
LIKELY HELP TO FUEL SOME NOCTURNAL THUNDERSTORMS.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
BERMUDA RIDGE ALONG THE MID ATLANTIC TO SOUTHEAST COAST AND LOW
PRESSURE TROFFING ACROSS THE MID CONTINENT WILL MAINTAIN A WARM AND
HUMID SOUTHWESTERLY FLOW ACROSS THE REGION FOR THE REST OF THE WEEK.
A SMALL CUTOFF LOW OVER THE LOWER OHIO RIVER VALLEY WILL OPEN UP AND
BECOME ENTRAINED INTO THE UPPER FLOW ACROSS THE EASTERN GREAT LAKES
AND NORTHEASTERN STATES. THIS WILL BRING BACK UNSETTLED CONDITIONS
WITH CHANCES OF PRECIP ACROSS THE REGION ON TUESDAY AND WEDNESDAY...
AND A BETTER CHANCE OF ORGANIZED CONVECTION ON THURSDAY AS A COLD
FRONT CROSSES THE REGION. GFS BRINGS A GRAZING SHOT OF COOLER AIR AT
THE WEEKEND WHEREAS ECMWF SAGS THE FRONT ACROSS THE REGION WITHOUT
MUCH COOLING. THE WEEK WILL BE GENERALLY ABOVE AVERAGE WITH HIGHS IN
THE 80S...MID TO UPPER 80S ON WEDNESDAY...AND MUCH MILDER THAN
CLIMATOLOGY AT NIGHT WITH LOWS IN THE LOWER TO MID 60S...EVEN LOW
70S ON WEDNESDAY NIGHT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
A BAND OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS WILL CONTINUE TO
DRIFT SOUTHEAST ACROSS WESTERN NY AND THE WESTERN FINGER LAKES
THROUGH MID MORNING BEFORE WEAKENING AND BECOMING SCATTERED IN
NATURE. ADDITIONAL MORE WIDELY SCATTERED SHOWERS AND STORMS ARE
EXPECTED TO DEVELOP THIS AFTERNOON MAINLY INLAND FROM THE IMMEDIATE
LAKESHORES WITH DAYTIME HEATING AND CONVERGENCE FROM DEVELOPING LAKE
BREEZE BOUNDARIES. VFR WILL PREVAIL...ALTHOUGH ANY OF THE STORMS
TODAY WILL PRODUCE LOCAL MVFR/IFR CONDITIONS.
ANY SCATTERED CONVECTION WILL END EARLY THIS EVENING WITH CLEARING
SKIES. THE CLEAR SKIES AND STILL ABUNDANT LOW LEVEL MOISTURE WILL
ALLOW FOR PATCHY FOG TO DEVELOP OVERNIGHT WITH AREAS OF MVFR/IFR
VSBY AFTER 06Z.
OUTLOOK...
SUNDAY AND SUNDAY NIGHT...VFR.
MONDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
TUESDAY...MAINLY VFR WITH SCATTERED SHOWERS AND THUNDERSTORMS.
WEDNESDAY...MAINLY VFR WITH A CHANCE OF SHOWERS AND THUNDERSTORMS.
&&
.MARINE...
HIGH PRESSURE AT THE SURFACE...COMBINED WITH STABLE LOW LEVEL LAPSE
RATES WILL YIELD RELATIVELY FLAT WAVE ACTION ON THE EASTERN TWO
GREAT LAKES THROUGH THE WEEKEND. AFTERNOON WINDS WILL INCREASE
TOWARDS 10 TO 12 KNOTS ON THE LAKES AND RIVERS.
WAVES AND WINDS WILL INCREASE SOME MONDAY WITH THE NEXT WEATHER
SYSTEM...THOUGH CONDITIONS MAY REMAIN BELOW SMALL CRAFT ADVISORY
CRITERIA.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HITCHCOCK/THOMAS
NEAR TERM...HITCHCOCK/THOMAS
SHORT TERM...CHURCH
LONG TERM...CHURCH/WCH
AVIATION...HITCHCOCK/THOMAS
MARINE...THOMAS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
336 AM EDT SAT AUG 15 2015
.SYNOPSIS...
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE ACROSS THE AREA
ON SATURDAY DEVELOPING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. DRIER AIR WILL MOVE IN FOR SATURDAY NIGHT AND
SUNDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION. THIS WILL RESULT IN A WARMING TREND WITH HIGHS IN THE
UPPER 70S TO LOWER 80S ON SATURDAY...AND IN THE 80S TO AROUND 90
ON SUNDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 132 AM EDT SATURDAY...AS THE 500 MB TROUGH SLIDES CLOSER TO
THE FORECAST AREA SHOWERS ARE CONTINUING TO MOVE ALONG THE SURFACE
FRONTAL BOUNDARY WHICH IS NOW LOCATED ALONG AN AXIS MIRRORING THE
CANADIAN BORDER FROM LAKE ERIE THROUGH LAKE ONTARIO. LATEST HRRR
AND RAP GUIDANCE KEEPS THE MCS THAT IS CURRENTLY ACROSS LAKE
ONTARIO SOUTH OF THE FORECAST AREA. THESE MODELS DO DEVELOP A FEW
ISOLATED SHOWERS ACROSS THE ADIRONDACKS AS THE ENERGY FROM THE
VORT MAX RIDES UP THE ADIRONDACKS SO I DID REINTRODUCE SOME
ISOLATED WORDING BACK INTO THE FORECAST AS THERE SHOULD BE
SUFFICIENT LIFT FOR A FEW SHOWERS TO DEVELOP OVERNIGHT.
ADDITIONALLY WITH THE CLEARING THAT IS DEVELOPING OVER THE
CONNECTICUT RIVER VALLEY I ANTICIPATE SOME FOG DEVELOPING HOWEVER
I`M NOT ENTIRELY CONFIDENT HOW LARGE THE AREA WILL BE SO I JUST
ADDED IN FOG TO THE CLIMO FAVOURED AREAS IN THE CONNECTICUT RIVER
VALLEY AND FOR PORTIONS OF THE LAMOILLE RIVER VALLEY AS WELL.
PREVIOUS DISCUSSION AS OF 1050 PM EDT FRIDAY...COMPOSITE RADAR
LOOP SHOWING JUST A FEW WIDELY SCATTERED SHOWERS ACROSS NORTHEAST
VERMONT. EXPECTING THIS ACTIVITY TO COME TO AN END AROUND
MIDNIGHT. HAVE REDUCED POPS AGAIN FOR THE OVERNIGHT PERIOD TO
REFLECT THIS DIMINISHED SHOWER ACTIVITY.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH MONDAY/...
AS OF 330 PM EDT FRIDAY...UPPER TROUGH MOVES SLOWLY ACROSS THE
AREA DURING THE MORNING HOURS ON SATURDAY. INSTABILITY SHOULD BE
LIMITED DESPITE THE MORE FAVORABLE DYNAMIC SUPPORT AND LOOKING AT
SCATTERED SHOWERS AGAIN...WITH ANY THREAT FOR THUNDER COMING MORE
IN THE AFTERNOON HOURS WHEN DYNAMIC SUPPORT WILL BE WEAKENING AND
INSTABILITY INCREASING A BIT. NOT THE MOST FAVORABLE OF SITUATIONS
SO THE IDEA OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS...
ESPECIALLY FROM THE NORTHERN ADIRONDACKS EASTWARD LOOKS GOOD.
RIDGING ALOFT BUILDS IN SATURDAY NIGHT AND BECOMES ESTABLISHED
OVER THE AREA SUNDAY AND SUNDAY NIGHT. THIS WILL ALLOW FOR A
WARMING TREND TO TAKE PLACE. LOOKING AT HIGHS IN THE UPPER 70S TO
LOWER 80S ON SATURDAY...BUT THEN IN THE 80S TO AROUND 90 ON SUNDAY
WITH PLENTY OF SUN AND NO PRECIPITATION.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 327 AM EDT SATURDAY...CONTINUED HOT AND HUMID WEATHER IS
ANTICIPATED FOR MUCH OF NEXT WEEK. ANOMOLOUSLY STRONG 500MB NORTH
PACIFIC RIDGE WILL CONTINUE TO FAVOR DOWNSTREAM TROUGH ACROSS THE
PAC NW AND NRN PLAINS...WHILE UPPER RIDGING PERSISTS IN THE MEAN
ALONG THE U.S. EAST COAST THROUGH AT LEAST THURSDAY.
THEREAFTER...PROGRESSIVE MID-LEVEL TROUGH SHIFTING NEWD FROM THE
UPR MS VALLEY AND GREAT LAKES AND SHEARING OUT TO OUR NORTH AND
WEST COULD BRING SLIGHTLY COOLER/MORE SEASONABLE CONDITIONS BY
FRIDAY BASED ON 00Z GFS AND 00Z ECMWF . IN THE
INTERIM...MAINTAINENCE OF S-SW LOW-LEVEL FLOW AND HUMID AIR MASS
(MID TO UPR 60S DEWPOINTS) WITH 850MB TEMPS IN EXCESS OF +16C WILL
YIELD DAILY HIGH TEMPS IN THE 85-90F RANGE TUESDAY THROUGH
THURSDAY. CHANCES EXIST FOR A FEW AIR MASS TYPE THUNDERSTORMS
DURING THE DAY TUESDAY AND AGAIN WEDNESDAY...BUT OVERALL
ORGANIZATION IS EXPECTED TO BE LIMITED BY WEAK DEEP LAYER SHEAR
AND OVERALL LACK OF STRONG SYNOPTIC- SCALE CONVERGENCE. POPS
GENERALLY 20-40 PERCENT RANGE TUESDAY AND WEDNESDAY. MAY SEE MORE
ORGANIZED BAND OF SHOWER AND THUNDERSTORMS SOMETIME THURSDAY NIGHT
INTO FRIDAY WITH POTENTIAL UPPER TROUGH AND TRAILING FRONTAL
PASSAGE. WILL CONTINUE TO MONITOR.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...MIXED CLOUD CONDITIONS THROUGH THE PERIOD AS
COMPACT UPPER TROUGH ACROSS SERN ONTARIO TRANSLATES EWD ACROSS
NORTHERN NY AND INTO VERMONT LATER THIS MORNING. WILL SEE SOME
MVFR CEILINGS AT MSS/SLK THROUGH 12Z ASSOCIATED WITH THIS FEATURE
AND MOIST LOW-LVL CONDITIONS. A FEW BREAKS FURTHER EAST WILL YIELD
POTENTIAL LIFR FOG AT MPV 08-12Z BEFORE DISSIPATING. ALSO HAVE THE
POTENTIAL FOR AN ISOLD SHOWER ACROSS NRN NY 08-12Z...AND THEN
AREAWIDE DURING THE DAYLIGHT HRS ASSOCIATED WITH LOW-LEVEL HEATING
AND UPPER LOW PASSAGE. GENERALLY CARRIED VCSH IN THE TAFS AT THIS
POINT AFTER 13-14Z THROUGH EARLY EVENING GIVEN TIMING AND
OCCURRENCE UNCERTAINITY AT INDIVIDUAL AIRPORTS. WINDS LIGHT AND
LESS THAN 5-6 KNOTS THROUGH THE PERIOD...GENERALLY OUT OF THE
SOUTH THROUGH 12Z...THEN BECOMING LIGHT WEST TO NW.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...SCATTERED SHOWERS/TSTMS
POSSIBLE MONDAY NIGHT THROUGH TUESDAY AS WEAK FRONTAL BOUNDARY
WASHES OUT NEAR THE INTL BORDER. ADDITIONAL DAYTIME SHOWERS/TSTMS
POSSIBLE WITH HUMID AIR MASS IN PLACE WEDNESDAY AFTERNOON. ANY
SHOWERS OR TSTMS COULD RESULT IN BRIEF INTERVALS OF MVFR/IFR
CONDITIONS...BUT GENERALLY VFR ON BALANCE FOR THE PERIOD.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...WGH/DEAL
SHORT TERM...EVENSON
LONG TERM...BANACOS
AVIATION...BANACOS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
159 AM EDT SAT AUG 15 2015
.SYNOPSIS...
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE ACROSS THE AREA
ON SATURDAY DEVELOPING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. DRIER AIR WILL MOVE IN FOR SATURDAY NIGHT AND
SUNDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION. THIS WILL RESULT IN A WARMING TREND WITH HIGHS IN THE
UPPER 70S TO LOWER 80S ON SATURDAY...AND IN THE 80S TO AROUND 90
ON SUNDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 132 AM EDT SATURDAY...AS THE 500 MB TROUGH SLIDES CLOSER TO
THE FORECAST AREA SHOWERS ARE CONTINUING TO MOVE ALONG THE SURFACE
FRONTAL BOUNDARY WHICH IS NOW LOCATED ALONG AN AXIS MIRRORING THE
CANADIAN BORDER FROM LAKE ERIE THROUGH LAKE ONTARIO. LATEST HRRR
AND RAP GUIDANCE KEEPS THE MCS THAT IS CURRENTLY ACROSS LAKE
ONTARIO SOUTH OF THE FORECAST AREA. THESE MODELS DO DEVELOP A FEW
ISOLATED SHOWERS ACROSS THE ADIRONDACKS AS THE ENERGY FROM THE
VORT MAX RIDES UP THE ADIRONDACKS SO I DID REINTRODUCE SOME
ISOLATED WORDING BACK INTO THE FORECAST AS THERE SHOULD BE
SUFFICIENT LIFT FOR A FEW SHOWERS TO DEVELOP OVERNIGHT.
ADDITIONALLY WITH THE CLEARING THAT IS DEVELOPING OVER THE
CONNECTICUT RIVER VALLEY I ANTICIPATE SOME FOG DEVELOPING HOWEVER
I`M NOT ENTIRELY CONFIDENT HOW LARGE THE AREA WILL BE SO I JUST
ADDED IN FOG TO THE CLIMO FAVOURED AREAS IN THE CONNECTICUT RIVER
VALLEY AND FOR PORTIONS OF THE LAMOILLE RIVER VALLEY AS WELL.
PREVIOUS DISCUSSION AS OF 1050 PM EDT FRIDAY...COMPOSITE RADAR
LOOP SHOWING JUST A FEW WIDELY SCATTERED SHOWERS ACROSS NORTHEAST
VERMONT. EXPECTING THIS ACTIVITY TO COME TO AN END AROUND
MIDNIGHT. HAVE REDUCED POPS AGAIN FOR THE OVERNIGHT PERIOD TO
REFLECT THIS DIMINISHED SHOWER ACTIVITY.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 330 PM EDT FRIDAY...UPPER TROUGH MOVES SLOWLY ACROSS THE
AREA DURING THE MORNING HOURS ON SATURDAY. INSTABILITY SHOULD BE
LIMITED DESPITE THE MORE FAVORABLE DYNAMIC SUPPORT AND LOOKING AT
SCATTERED SHOWERS AGAIN...WITH ANY THREAT FOR THUNDER COMING MORE
IN THE AFTERNOON HOURS WHEN DYNAMIC SUPPORT WILL BE WEAKENING AND
INSTABILITY INCREASING A BIT. NOT THE MOST FAVORABLE OF SITUATIONS
SO THE IDEA OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS...
ESPECIALLY FROM THE NORTHERN ADIRONDACKS EASTWARD LOOKS GOOD.
RIDGING ALOFT BUILDS IN SATURDAY NIGHT AND BECOMES ESTABLISHED
OVER THE AREA SUNDAY AND SUNDAY NIGHT. THIS WILL ALLOW FOR A
WARMING TREND TO TAKE PLACE. LOOKING AT HIGHS IN THE UPPER 70S TO
LOWER 80S ON SATURDAY...BUT THEN IN THE 80S TO AROUND 90 ON SUNDAY
WITH PLENTY OF SUN AND NO PRECIPITATION.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 334 PM EDT FRIDAY...VERY LITTLE HAS CHANGED SINCE THIS
MORNING`S EXTENDED FORECAST. STRONG NORTH PACIFIC RIDGE STILL
LOOKS TO KEEP UPPER RIDGING IN THE MEAN ALONG THE U.S. EAST COAST.
MONDAY WILL LIKELY BE THE HOTTEST DAY OF THE EXTENDED PERIOD WITH
850MB TEMPS AROUND +18C IN ECMWF AND GFS SUPPORTING VALLEY HIGHS
88-92F MONDAY AFTERNOON. MID-LEVEL RIDGE BRIEFLY BREAKS DOWN
MONDAY NIGHT AND TUESDAY...WITH WEAK FRONTAL ZONE SHIFTING SEWD
FROM ONTARIO BRINGING BEST CHANCES FOR SHOWERS AND THUNDERSTORMS
DURING THE DAY TUESDAY (40-50 POPS)...ESPECIALLY ACROSS THE
NORTHERN ZONES. THIS WILL RESULT IN HIGHS IN THE LOW-MID 80S.
FRONT QUICKLY DISSIPATES/WASHES OUT AND NEXT SURGE OF LOW-LEVEL
SWLY FLOW AND HIGHER HUMIDITY BRINGS HIGH TEMPS BACK INTO THE MID
TO POSSIBLE UPPER 80S WEDNESDAY AND THURSDAY. MAINTAINED 20-30
POPS DURING THE DAYLIGHT HRS WEDNESDAY AND THURSDAY WITH A FEW
SHOWERS OR THUNDERSTORMS POSSIBLE. ANOTHER FRONTAL SYSTEM WILL
APPROACH OUT AT DAY 7 FOR NEXT CHANCE OF ANY SIGNIFICANT
PRECIPITATION.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 12Z SUNDAY...MIXED CLOUD CONDITIONS THROUGH THE PERIOD AS
COMPACT UPPER TROUGH ACROSS SERN ONTARIO TRANSLATES EWD ACROSS
NORTHERN NY AND INTO VERMONT LATER THIS MORNING. WILL SEE SOME
MVFR CEILINGS AT MSS/SLK THROUGH 12Z ASSOCIATED WITH THIS FEATURE
AND MOIST LOW-LVL CONDITIONS. A FEW BREAKS FURTHER EAST WILL YIELD
POTENTIAL LIFR FOG AT MPV 08-12Z BEFORE DISSIPATING. ALSO HAVE THE
POTENTIAL FOR AN ISOLD SHOWER ACROSS NRN NY 08-12Z...AND THEN
AREAWIDE DURING THE DAYLIGHT HRS ASSOCIATED WITH LOW-LEVEL HEATING
AND UPPER LOW PASSAGE. GENERALLY CARRIED VCSH IN THE TAFS AT THIS
POINT AFTER 13-14Z THROUGH EARLY EVENING GIVEN TIMING AND
OCCURRENCE UNCERTAINITY AT INDIVIDUAL AIRPORTS. WINDS LIGHT AND
LESS THAN 5-6 KNOTS THROUGH THE PERIOD...GENERALLY OUT OF THE
SOUTH THROUGH 12Z...THEN BECOMING LIGHT WEST TO NW.
OUTLOOK 12Z SUNDAY THROUGH WEDNESDAY...SCATTERED SHOWERS/TSTMS
POSSIBLE MONDAY NIGHT THROUGH TUESDAY AS WEAK FRONTAL BOUNDARY
WASHES OUT NEAR THE INTL BORDER. ADDITIONAL DAYTIME SHOWERS/TSTMS
POSSIBLE WITH HUMID AIR MASS IN PLACE WEDNESDAY AFTERNOON. ANY
SHOWERS OR TSTMS COULD RESULT IN BRIEF INTERVALS OF MVFR/IFR
CONDITIONS...BUT GENERALLY VFR ON BALANCE FOR THE PERIOD.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...WGH/DEAL
SHORT TERM...EVENSON
LONG TERM...NEILES
AVIATION...BANACOS
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
143 AM EDT SAT AUG 15 2015
.SYNOPSIS...
AN UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE ACROSS THE AREA
ON SATURDAY DEVELOPING SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS. DRIER AIR WILL MOVE IN FOR SATURDAY NIGHT AND
SUNDAY AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE BUILDS INTO THE
REGION. THIS WILL RESULT IN A WARMING TREND WITH HIGHS IN THE
UPPER 70S TO LOWER 80S ON SATURDAY...AND IN THE 80S TO AROUND 90
ON SUNDAY.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
AS OF 132 AM EDT SATURDAY...AS THE 500 MB TROUGH SLIDES CLOSER TO
THE FORECAST AREA SHOWERS ARE CONTINUING TO MOVE ALONG THE SURFACE
FRONTAL BOUNDARY WHICH IS NOW LOCATED ALONG AN AXIS MIRRORING THE
CANADIAN BORDER FROM LAKE ERIE THROUGH LAKE ONTARIO. LATEST HRRR
AND RAP GUIDANCE KEEPS THE MCS THAT IS CURRENTLY ACROSS LAKE
ONTARIO SOUTH OF THE FORECAST AREA. THESE MODELS DO DEVELOP A FEW
ISOLATED SHOWERS ACROSS THE ADIRONDACKS AS THE ENERGY FROM THE
VORT MAX RIDES UP THE ADIRONDACKS SO I DID REINTRODUCE SOME
ISOLATED WORDING BACK INTO THE FORECAST AS THERE SHOULD BE
SUFFICIENT LIFT FOR A FEW SHOWERS TO DEVELOP OVERNIGHT.
ADDITIONALLY WITH THE CLEARING THAT IS DEVELOPING OVER THE
CONNECTICUT RIVER VALLEY I ANTICIPATE SOME FOG DEVELOPING HOWEVER
I`M NOT ENTIRELY CONFIDENT HOW LARGE THE AREA WILL BE SO I JUST
ADDED IN FOG TO THE CLIMO FAVOURED AREAS IN THE CONNECTICUT RIVER
VALLEY AND FOR PORTIONS OF THE LAMOILLE RIVER VALLEY AS WELL.
PREVIOUS DISCUSSION AS OF 1050 PM EDT FRIDAY...COMPOSITE RADAR
LOOP SHOWING JUST A FEW WIDELY SCATTERED SHOWERS ACROSS NORTHEAST
VERMONT. EXPECTING THIS ACTIVITY TO COME TO AN END AROUND
MIDNIGHT. HAVE REDUCED POPS AGAIN FOR THE OVERNIGHT PERIOD TO
REFLECT THIS DIMINISHED SHOWER ACTIVITY.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH SUNDAY NIGHT/...
AS OF 330 PM EDT FRIDAY...UPPER TROUGH MOVES SLOWLY ACROSS THE
AREA DURING THE MORNING HOURS ON SATURDAY. INSTABILITY SHOULD BE
LIMITED DESPITE THE MORE FAVORABLE DYNAMIC SUPPORT AND LOOKING AT
SCATTERED SHOWERS AGAIN...WITH ANY THREAT FOR THUNDER COMING MORE
IN THE AFTERNOON HOURS WHEN DYNAMIC SUPPORT WILL BE WEAKENING AND
INSTABILITY INCREASING A BIT. NOT THE MOST FAVORABLE OF SITUATIONS
SO THE IDEA OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS...
ESPECIALLY FROM THE NORTHERN ADIRONDACKS EASTWARD LOOKS GOOD.
RIDGING ALOFT BUILDS IN SATURDAY NIGHT AND BECOMES ESTABLISHED
OVER THE AREA SUNDAY AND SUNDAY NIGHT. THIS WILL ALLOW FOR A
WARMING TREND TO TAKE PLACE. LOOKING AT HIGHS IN THE UPPER 70S TO
LOWER 80S ON SATURDAY...BUT THEN IN THE 80S TO AROUND 90 ON SUNDAY
WITH PLENTY OF SUN AND NO PRECIPITATION.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 334 PM EDT FRIDAY...VERY LITTLE HAS CHANGED SINCE THIS
MORNING`S EXTENDED FORECAST. STRONG NORTH PACIFIC RIDGE STILL
LOOKS TO KEEP UPPER RIDGING IN THE MEAN ALONG THE U.S. EAST COAST.
MONDAY WILL LIKELY BE THE HOTTEST DAY OF THE EXTENDED PERIOD WITH
850MB TEMPS AROUND +18C IN ECMWF AND GFS SUPPORTING VALLEY HIGHS
88-92F MONDAY AFTERNOON. MID-LEVEL RIDGE BRIEFLY BREAKS DOWN
MONDAY NIGHT AND TUESDAY...WITH WEAK FRONTAL ZONE SHIFTING SEWD
FROM ONTARIO BRINGING BEST CHANCES FOR SHOWERS AND THUNDERSTORMS
DURING THE DAY TUESDAY (40-50 POPS)...ESPECIALLY ACROSS THE
NORTHERN ZONES. THIS WILL RESULT IN HIGHS IN THE LOW-MID 80S.
FRONT QUICKLY DISSIPATES/WASHES OUT AND NEXT SURGE OF LOW-LEVEL
SWLY FLOW AND HIGHER HUMIDITY BRINGS HIGH TEMPS BACK INTO THE MID
TO POSSIBLE UPPER 80S WEDNESDAY AND THURSDAY. MAINTAINED 20-30
POPS DURING THE DAYLIGHT HRS WEDNESDAY AND THURSDAY WITH A FEW
SHOWERS OR THUNDERSTORMS POSSIBLE. ANOTHER FRONTAL SYSTEM WILL
APPROACH OUT AT DAY 7 FOR NEXT CHANCE OF ANY SIGNIFICANT
PRECIPITATION.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
THROUGH 00Z SUNDAY...MAINLY VFR EXPECTED THROUGH THE PERIOD...WITH
THE EXCEPTION OF SOME MVFR IN STRATUS AND POSSIBLE LIGHT FOG
OVERNIGHT/EARLY SATURDAY MORNING AT MPV/SLK. SHOWERS ARE COMING TO
AN END THIS EVENING...HOWEVER MULTIPLE DECKS OF VFR CLOUDS WILL
PERSIST THROUGH THE EVENING AND OVERNIGHT HOURS. SOME LOWER
CEILINGS ARE EXPECTED TO DEVELOP...WITH MVFR LIKELY FOR A TIME AT
SLK/MPV. ABUNDANCE OF CLOUDS SHOULD LIMIT FOG/BR DEVELOPMENT AS A
WHOLE...BUT WITH AMPLE LOW LEVEL MOISTURE...GENERALLY LIGHT
WINDS...AND SOME RAINFALL TODAY...SOME PATCHY FOG/BR MAY BE
AROUND. GREATEST RISK OF FOG/BR WILL BE AT SLK/MPV FROM 06Z-
12Z...AND HAVE SHOWN 3SM BR FOR NOW. CEILINGS SHOULD LIFT TO VFR
AND/OR SCATTER OUT SATURDAY MORNING BY 15Z AT THE LATEST. SOME
ADDITIONAL SCATTERED RAIN SHOWERS ALONG A COLD FRONT ALSO LIKELY
AS IT PROGRESSES FROM NW TO SE. HAVE SHOWN VCSH FOR NOW. WINDS
LIGHT AND LESS THAN 5-6 KNOTS THROUGH THE PERIOD...GENERALLY OUT
OF THE SOUTH/SOUTHWEST BEFORE FRONTAL PASSAGE TURNING NORTHWEST
AFTERWARDS.
OUTLOOK 00Z SUNDAY THROUGH WEDNESDAY...
00Z SUNDAY THROUGH WEDNESDAY...SCATTERED SHOWERS/TSTMS POSSIBLE
MONDAY EVENING INTO MONDAY NIGHT WITH APPROACH OF A COLD FRONT
FROM THE NORTH AND WEST. OTHERWISE...MAINLY VFR.
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...WGH/DEAL
SHORT TERM...EVENSON
LONG TERM...NEILES
AVIATION...MUCCILLI
AREA FORECAST DISCUSSION
NWS RALEIGH NC
146 PM EDT SAT AUG 15 2015
.SYNOPSIS...WEAK SURFACE HIGH PRESSURE...ALONG WITH A WEAK SURFACE
PIEDMONT TROUGH...PERSIST OVER THE REGION THROUGH THE REST OF THE
WEEKEND.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 925 AM SATURDAY...
MORNING UPPER-AIR SOUNDINGS SHOW CONTRAST IN THE AIR MASS BETWEEN
KMHX AND KGSO. THE KMHX SOUNDING IS NOTICEABLY DRIER AND CAPPED...
WHEREAS THE KGSO SOUNDING...WHILE CAPPED...IS MORE MOIST AND WITH A
CAP THAT IS WEAKER. THE PRECIPITABLE WATER VALUE AT KMHX IS 0.81...
BELOW NORMAL FOR THIS TIME OF YEAR...COMPARED WITH NEARLY 1.25
INCHES AT KGSO. MANY CONS REMAIN IN PLACE FOR PRECIPITATION TODAY...
INCLUDING RIDGING ALOFT...A GENERAL DRY AIR MASS IN THE MEAN...AND
FOR MUCH OF CENTRAL NORTH CAROLINA K INDICES THAT ARE IN THE TEENS
AT BEST WITH MINIMAL LOW-LEVEL CONVERGENCE. 850MB THETA-E VALUES AND
K INDICES ARE HIGHEST TOWARD THE YADKIN RIVER...AND IT IS THERE
WHERE THE RAP MODEL SOUNDINGS SHOW A SUFFICIENTLY WEAK CAP THAT
THERE COULD BE AN ISOLATED SHOWER OR THREE THIS AFTERNOON. THE
LATEST HRRR WRF GUIDANCE SHOWS LESS THAN A HANDFUL OF SHOWERS IN AN
AREA WEST OF ABOUT A LINE FROM KGSO TO KRCZ. A VERY ISOLATED SHOWER
COULD OCCUR ELSEWHERE IN DECENT 850MB UVV THIS AFTERNOON AS WINDS
ALOFT INCREASE SLIGHTLY WITH AN INCREASE IN MID-LEVEL MOISTURE AS
WELL AS NOTED ON WATER VAPOR IMAGERY...BUT LOW-LEVELS SEEM TOO DRY
AND STABLE TO RETURN THE MENTION TO THE FORECAST. HIGH TEMPERATURES
87 TO 92 WITH SUSTAINED WINDS UNDER 10 MPH...AND ONLY A COUPLE OF
BRIEF GUSTS A LITTLE ABOVE THAT EXPECTED TODAY. LITTLE CHANGE
TONIGHT...TRANQUIL WITH DRY AIR IN PLACE WITH LOWS IN THE 60S.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 250 AM SATURDAY...
LITTLE CHANGE IN THE PATTERN SUNDAY AND SUNDAY NIGHT...WITH OUR AREA
CAUGHT IN BETWEEN THE MAJOR WEATHER PLAYERS...NAMELY THE CLOSED LOW
OVER THE OH AND TN VALLEYS...A SHORT WAVE MOVING OFF THE NE COAST...
AND A RIDGE CENTERED OFF THE SE COAST. AT THE SFC...HIGH PRESSURE
WILL REMAIN POSITIONED JUST TO OUR NORTH...AND THE AIRMASS IS
PROGGED TO REMAIN RELATIVELY DRY FOR THIS TIME OF YEAR (PWAT STILL
HOLDING AT AROUND AN INCH). SO FOR NOW...WILL KEEP THE DRY FORECAST
GOING...ALTHOUGH SUNSHINE MAY BE FILTERED SOMEWHAT BY HIGH CLOUDS.
LITTLE AIRMASS CHANGE...SO HIGHS STILL A FEW DEGREES ABOVE NORMAL...
HIGHS IN THE UPPER 80S TO LOWER 90S AND LOWS SUNDAY NIGHT IN THE MID-
UPR 60S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 250 AM SATURDAY...
RIDGING OVER THE WESTERN ATLANTIC HOLDS TIGHT EARLY NEXT WEEK WITH
MOISTURE ON THE INCREASE BY MID-LATE WEEK IN DEEPENING SOUTHWEST
FLOW AS AN UPPER TROF MIGRATES ACROSS THE NORTHERN TIER OF THE
CONUS. HEIGHTS BUILD MODESTLY AHEAD OF THE UPPER TROF...WITH HIGHS
AT OR SLIGHTLY ABOVE CLIMATOLOGICAL NORMS MONDAY BOOSTED TO MAINLY
LOWER 90S WITH POTENTIAL FOR MID 90S BY LATE WEEK. SIMILARLY...
INITIAL LOW RAIN CHANCES EARLY IN THE WEEK WILL BE SKEWED TO DIURNAL
WITH VERY WEAK FORCING OR SHEAR.. POPS WILL BE INCREASING TO AT
LEAST CHANCE CATEGORY THURSDAY AND MORE SO ON FRIDAY IN A MORE
FAVORABLE DYNAMIC REGIME AHEAD OF THE UPPER TROF AND ITS ASSOCIATED
SURFACE FRONT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 145 PM SUNDAY...
VFR CONDITIONS WILL PERSIST THROUGH THE 18Z VALID TAF PERIOD OUTSIDE
OF ANY VERY ISOLATED SHOWER...AND PATCHY LATE NIGHT AND EARLY SUNDAY
MORNING LIGHT FOG MOST PARTICULARLY TOWARD KFAY AND KRWI. UNDER A
VERY WEAK SURFACE FLOW...GUIDANCE IS QUITE VARIED IN TERMS OF
SURFACE WIND DIRECTIONS AND LEANED TOWARD THE CONSENSUS OF GUIDANCE
IN TERMS OF A WIND DIRECTION IN THE TERMINAL FORECASTS WHERE THERE
WAS MORE CONFIDENCE TO DO SO. SUSTAINED WINDS WILL BE UNDER 10KT AND
FREQUENTLY 5KT OR LESS.
BEYOND THE 18Z VALID TAF PERIOD...GENERAL PERSISTENCE IN THE
FORECAST SUNDAY INTO MONDAY. IF ISOLATED SHOWERS ARE TO OCCUR THEY
WOULD MOST LIKELY OCCUR OVER THE WESTERN PIEDMONT...LEAST TOWARD
KRWI...THROUGH THEN. MOISTURE INCREASES TUESDAY AND ALONG WITH THAT
MOISTURE COMES BETTER CHANCES FOR AT LEAST SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS CENTRAL NORTH CAROLINA. THOSE CONDITIONS
PERSIST THROUGH THURSDAY COUPLED WITH THE POTENTIAL FOR OVERNIGHT
AND EARLY MORNING AREAS OF SUB-VFR CONDITIONS IN LOW CLOUDS AND FOG.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...RAH
LONG TERM...MLM
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
925 AM EDT SAT AUG 15 2015
.SYNOPSIS...HIGH PRESSURE AND DRY AIR WILL PROVIDE MAINLY FAIR
WEATHER...ALONG WITH NEAR-NORMAL TEMPERATURES...ACROSS CENTRAL NORTH
CAROLINA THIS WEEKEND.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 925 AM SATURDAY...
MORNING UPPER-AIR SOUNDINGS SHOW CONTRAST IN THE AIR MASS BETWEEN
KMHX AND KGSO. THE KMHX SOUNDING IS NOTICEABLY DRIER AND CAPPED...
WHEREAS THE KGSO SOUNDING...WHILE CAPPED...IS MORE MOIST AND WITH A
CAP THAT IS WEAKER. THE PRECIPITABLE WATER VALUE AT KMHX IS 0.81...
BELOW NORMAL FOR THIS TIME OF YEAR...COMPARED WITH NEARLY 1.25
INCHES AT KGSO. MANY CONS REMAIN IN PLACE FOR PRECIPITATION TODAY...
INCLUDING RIDGING ALOFT...A GENERAL DRY AIR MASS IN THE MEAN...AND
FOR MUCH OF CENTRAL NORTH CAROLINA K INDICES THAT ARE IN THE TEENS
AT BEST WITH MINIMAL LOW-LEVEL CONVERGENCE. 850MB THETA-E VALUES AND
K INDICES ARE HIGHEST TOWARD THE YADKIN RIVER...AND IT IS THERE
WHERE THE RAP MODEL SOUNDINGS SHOW A SUFFICIENTLY WEAK CAP THAT
THERE COULD BE AN ISOLATED SHOWER OR THREE THIS AFTERNOON. THE
LATEST HRRR WRF GUIDANCE SHOWS LESS THAN A HANDFUL OF SHOWERS IN AN
AREA WEST OF ABOUT A LINE FROM KGSO TO KRCZ. A VERY ISOLATED SHOWER
COULD OCCUR ELSEWHERE IN DECENT 850MB UVV THIS AFTERNOON AS WINDS
ALOFT INCREASE SLIGHTLY WITH AN INCREASE IN MID-LEVEL MOISTURE AS
WELL AS NOTED ON WATER VAPOR IMAGERY...BUT LOW-LEVELS SEEM TOO DRY
AND STABLE TO RETURN THE MENTION TO THE FORECAST. HIGH TEMPERATURES
87 TO 92 WITH SUSTAINED WINDS UNDER 10 MPH...AND ONLY A COUPLE OF
BRIEF GUSTS A LITTLE ABOVE THAT EXPECTED TODAY. LITTLE CHANGE
TONIGHT...TRANQUIL WITH DRY AIR IN PLACE WITH LOWS IN THE 60S.
&&
.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 250 AM SATURDAY...
LITTLE CHANGE IN THE PATTERN SUNDAY AND SUNDAY NIGHT...WITH OUR AREA
CAUGHT IN BETWEEN THE MAJOR WEATHER PLAYERS...NAMELY THE CLOSED LOW
OVER THE OH AND TN VALLEYS...A SHORT WAVE MOVING OFF THE NE COAST...
AND A RIDGE CENTERED OFF THE SE COAST. AT THE SFC...HIGH PRESSURE
WILL REMAIN POSITIONED JUST TO OUR NORTH...AND THE AIRMASS IS
PROGGED TO REMAIN RELATIVELY DRY FOR THIS TIME OF YEAR (PWAT STILL
HOLDING AT AROUND AN INCH). SO FOR NOW...WILL KEEP THE DRY FORECAST
GOING...ALTHOUGH SUNSHINE MAY BE FILTERED SOMEWHAT BY HIGH CLOUDS.
LITTLE AIRMASS CHANGE...SO HIGHS STILL A FEW DEGREES ABOVE NORMAL...
HIGHS IN THE UPPER 80S TO LOWER 90S AND LOWS SUNDAY NIGHT IN THE MID-
UPR 60S.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 250 AM SATURDAY...
RIDGING OVER THE WESTERN ATLANTIC HOLDS TIGHT EARLY NEXT WEEK WITH
MOISTURE ON THE INCREASE BY MID-LATE WEEK IN DEEPENING SOUTHWEST
FLOW AS AN UPPER TROF MIGRATES ACROSS THE NORTHERN TIER OF THE
CONUS. HEIGHTS BUILD MODESTLY AHEAD OF THE UPPER TROF...WITH HIGHS
AT OR SLIGHTLY ABOVE CLIMATOLOGICAL NORMS MONDAY BOOSTED TO MAINLY
LOWER 90S WITH POTENTIAL FOR MID 90S BY LATE WEEK. SIMILARLY...
INITIAL LOW RAIN CHANCES EARLY IN THE WEEK WILL BE SKEWED TO DIURNAL
WITH VERY WEAK FORCING OR SHEAR.. POPS WILL BE INCREASING TO AT
LEAST CHANCE CATEGORY THURSDAY AND MORE SO ON FRIDAY IN A MORE
FAVORABLE DYNAMIC REGIME AHEAD OF THE UPPER TROF AND ITS ASSOCIATED
SURFACE FRONT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 640 AM SATURDAY...
THROUGH 12Z SUNDAY: VFR CONDITIONS AND LIGHT WINDS ARE EXPECTED
THROUGH 16/06Z...WITH SHALLOW TO MODERATE CU THIS AFTERNOON AT OR
ABOVE 5K FT AGL. AFT 16/06Z...PATCHY FOG WITH MVFR FLT CONDITIONS IS
POSSIBLE...MAINLY ACROSS THE COASTAL PLAIN REGION AND I-95
CORRIDOR...AND AT KFAY/KRWI.
AFT 12Z SUN...MAINLY VFR CONDITIONS ARE EXPECTED THE REST OF THE
WEEKEND INTO MONDAY...WITH THE NEXT CHANCE FOR WIDESPREAD SUB-VFR
CONDITIONS MONDAY NIGHT INTO TUESDAY AS THE CLOSED LOW CURRENTLY TO
OUR WEST GRADUALLY DRIFTS EAST TOWARD OUR AREA...AND DEEP MOISTURE
AHEAD OF IT ADVECTS INTO THE CAROLINAS.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RAH
NEAR TERM...DJF
SHORT TERM...RAH
LONG TERM...MLM
AVIATION...RAH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
953 PM CDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 953 PM CDT SUN AUG 16 2015
BLENDED IN CURRENT CONDITIONS TO THE FORECAST WITH ONLY ISOLATED
SHOWERS LEFT IN THE SOUTHERN JAMES RIVER VALLEY. AFTER
COLLABORATION WITH SURROUNDING OFFICES...OPTED TO REMOVE THE
OVERNIGHT POP IN SOUTHWEST NORTH DAKOTA. THE LATEST NAM KEEPS IT
DRY IN THAT REGION OVERNIGHT...AND THAT LINES UP WITH HRRR AND RAP
13 TOO. ONE AREA TO MONITOR OVERNIGHT FOR A POTENTIAL SHOWER IS
THE NORTH CENTRAL WHERE THE RAP 13 AND HRRR BOTH HINT AT THE
POSSIBILITY LATE TONIGHT / EARLY MONDAY MORNING.
UPDATE ISSUED AT 902 PM CDT SUN AUG 16 2015
MADE ANOTHER QUICK UPDATE AS THE SHOWERS CONTINUE THEIR TREK
EASTWARD. DECIDED TO REMOVE THE MENTION OF THUNDER WITH ONLY
LIMITED INSTABILITY AVAILABLE.
UPDATE ISSUED AT 654 PM CDT SUN AUG 16 2015
MAIN CHANGE WAS TO HOLD ONTO SHOWERS / ISOLATED THUNDERSTORMS A
COUPLE MORE HOURS THIS EVENING. THE SHORT TERM MODELS HAVE
STRUGGLED TO HANDLE THE ONGOING PRECIPITATION. IT APPEARS MUCH OF
THE ACTIVITY IS IN ASSOCIATION WITH THE RIGHT REAR QUADRANT OF AN
UPPER LEVEL JET STREAK. THIS FEATURE IS FORECAST TO WEAKEN THIS
EVENING AS IT MOVE SOUTH AND EAST. WILL STILL TREND TO A DRY
FORECAST LATER THIS EVENING. HAVE ALSO INCREASED SKY COVER THIS
EVENING IN ASSOCIATION WITH THE PRECIPITATION.
UPDATE ISSUED AT 521 PM CDT SUN AUG 16 2015
QUICK UPDATE TO SPREAD THE ISOLATED SHOWERS / THUNDERSTORMS A ROW
OF COUNTIES FARTHER EAST. WE ALSO BLENDED IN CURRENT CONDITIONS...
OTHERWISE THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM CDT SUN AUG 16 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER NORTHERN ONTARIO WITH
COLD FRONT DROPPING THROUGH THE UPPER MIDWEST INTO THE CENTRAL
PLAINS. COOL HIGH PRESSURE CONTINUES TO SLIDE OVER THE NORTHERN
ROCKIES INTO THE NORTHERN PLAINS BRINGING REFRESHING TEMPERATURES
AFTER A HOT DAY YESTERDAY. UPPER LEVEL ANALYSIS BRING CYCLONIC
WEST/SOUTHWESTERLY FLOW TO THE AREA WITH A VARIETY OF WEAK SHORT
WAVES NOTED AND UPPER JET STREAK PASSING THROUGH. THIS CONTINUES
TO BRING SOME WEAK SHOWERS/THUNDERSTORMS TO SOUTHERN/WESTERN
PORTIONS OF THE AREA.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...SHOWERS/WEAK STORMS
OVER THE SOUTHERN JAMES RIVER VALLEY WILL CONTINUE TO PUSH OFF TO
THE EAST...WHILE PRECIPITATION OVER THE WESTERN PORTIONS OF THE
STATE AFFILIATED WITH PASSING JET STREAK MAY LINGER INTO THE
EARLY EVENING BEFORE DISSIPATING. WITH LIMITED INSTABILITY TO DEAL
WITH...STORMS SHOULD REMAIN WEAK. A COOL NIGHT IS EXPECTED AS
SURFACE HIGH SETTLES OVER THE REGION.
ON MONDAY...BROAD CYCLONIC FLOW REMAINS OVER THE REGION WITH
PRECIPITATION CHANCES INCREASING PRIMARILY OVER SOUTHWESTERN AREAS
THROUGH MID-DAY BEFORE SPREADING TOWARDS THE NORTHEAST LATER IN
THE DAY. WILL MENTION MAINLY SHOWERS BUT STILL KEEP LOW THUNDER
CHANCES IN THE FORECAST WITH MINIMAL INSTABILITY NOTED.
TEMPERATURES WILL REMAIN BELOW AVERAGE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 354 PM CDT SUN AUG 16 2015
THE FORECAST FOCUS IS ON THE POTENTIAL FOR TWO RAIN EVENTS THIS
WEEK.
MODELS AND ENSEMBLES AGREE THAT BROAD SCALE CYCLONIC FLOW ACROSS THE
NORTHERN TIER WILL DIRECT TWO MIDDLE LEVEL ALASKA SHORTWAVES INTO
THE DAKOTAS AND SOUTHERN CANADA THIS WEEK. LARGE SCALE ASCENT
ASSOCIATED WITH THE FIRST WILL SPREAD ACROSS NORTH DAKOTA BEGINNING
ON MONDAY NIGHT...AND WILL SUPPORT PRECIPITATION THROUGH TUESDAY
EVENING...PER THE 06 UTC GEFS AND 12 UTC GFS/ECMWF/GEM GLOBAL.
CONVECTIVE INSTABILITY IS LIMITED IN GUIDANCE...SO GRIDDED FORECASTS
INDICATE ONLY A SLIGHT CHANCE FOR THUNDERSTORMS DESPITE LIKELY
SHOWERS.
THERE IS GREATER UNCERTAINTY WITH STRENGTH OF THE SECOND
SYSTEM...THOUGH THERE IS GOOD AGREEMENT THAT H5 HEIGHT FALLS WILL
SPREAD INTO WESTERN NORTH DAKOTA ON FRIDAY...WITH ASSOCIATED
THUNDERSTORM ACTIVITY LASTING INTO SUNDAY. THE 12 UTC ECMWF IS ON
THE AMPLIFIED SIDE OF THE 06 UTC GEFS ENSEMBLE SPREAD...AND THE 12
UTC GFS IS IN THE MIDDLE. SINCE THE SHORTWAVE WILL NOT CROSS THE
BERING STRAIT UNTIL WEDNESDAY...THE ENVELOPE OF SOLUTIONS WILL
PROBABLY HAVE LARGE SPREAD UNTIL MIDWEEK.
THE AFOREMENTIONED BROAD CYCLONIC FLOW WILL SUPPORT TEMPERATURES
NEAR OR BELOW NORMAL ACROSS THE NORTHERN HIGH PLAINS.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 643 PM CDT SUN AUG 16 2015
AN ISOLATED SHOWER OR THUNDERSTORM IS POSSIBLE AT KBIS AND KJMS
EARLY THIS EVENING...OTHERWISE EXPECT VFR CONDITIONS TO PREVAIL.
MAINLY MID AND HIGH LEVEL CLOUDINESS WILL DOMINATE...THOUGH SOME
CUMULUS AROUND 5KFT IS ALSO POSSIBLE AT TIMES. WINDS SHOULD
DIMINISH EARLY THIS EVENING...WITH SPEEDS THEN REMAINING LESS THAN
10 KTS THROUGH THE FORECAST PERIOD. A FEW SHOWERS COULD APPROACH
KDIK TOWARDS THE END OF THE FORECAST PERIOD...BUT LEFT THOSE OUT
FOR NOW.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...CK
SHORT TERM...JJS
LONG TERM...SCHECK
AVIATION...CK
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
641 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE SYSTEM WILL RESULT IN A CHANCE FOR
A FEW THUNDERSTORMS TODAY AND SUNDAY. TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL WITH AFTERNOON HIGHS IN THE MID TO UPPER 80S
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A DECAYING MCS IS SAGGING VERY SLOWLY SOUTHWARD ACROSS NORTHWEST
PORTIONS OF OUR FA EARLY THIS MORNING. EXPECT THE PCPN INTENSITY
AND COVERAGE TO CONTINUE TO DECREASE THROUGH DAYBREAK AS IT
PUSHES INTO A MORE STABLE AIRMASS ACROSS SOUTHERN PORTIONS OF OUR
FA.
ASSUMING THE CLOUDS FROM THE MCS DISSIPATE THROUGH THE LATE
MORNING HOURS...WE SHOULD BE ABLE TO DESTABILIZE ONCE AGAIN
THROUGH THIS AFTERNOON. THE NAM MAY BE OVERDONE WITH ITS
INSTABILITY BUT EVEN THE GFS AND RAP ARE INDICATING ML CAPES
PUSHING INTO THE 1500-2000 J/KG RANGE THIS AFTERNOON ACROSS ABOUT
THE NORTHWEST HALF OF OUR FA...DECREASING TO AROUND 1000 J/KG
ACROSS OUR SOUTHEAST. A WEAK UPPER LEVEL LOW ALONG WITH A SHEARED
OUT VORT AXIS IS FORECAST TO SAG SLOWLY SOUTHWEST ACROSS THE AREA
THROUGH THE AFTERNOON. THE COMBINATION OF THIS AND SOME POSSIBLE
LINGERING BOUNDARIES FROM THE CURRENT DECAYING MCS...MAY BE ENOUGH
TO PRODUCE SOME ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPMENT
THIS AFTERNOON. FORECAST SOUNDINGS ARE SHOWING VERY LIGHT WIND
FLOW ALL THE WAY UP TO 300 MB THIS AFTERNOON SO WOULD EXPECT
STORMS TO BE FAIRLY PULSY AND SLOW MOVING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE UPPER LEVEL LOW WILL RETROGRADE SLOWLY SOUTHWEST THROUGH THE
DAY ON SUNDAY BEFORE BEGINNING TO WORK BACK TO THE EAST SUNDAY
NIGHT INTO MONDAY. FORCING WILL BE WEAK...BUT AS WE DESTABILIZE
THROUGH THE AFTERNOON...IT WILL BE TOUGH TO RULE OUT A FEW
SHOWERS AND THUNDERSTORMS BOTH SUNDAY AND MONDAY. WILL LIMIT POPS
TO JUST 20-30 PERCENT WITH THE BEST CHANCE IN THE DIURNALLY
FAVORABLE AFTERNOON TO EARLY EVENING. HIGH TEMPERATURES WILL
REMAIN SLIGHTLY ABOVE NORMAL...PUSHING INTO THE MID TO UPPER 80S
BOTH DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ANOTHER DISTURBANCE MOVES ACROSS PRIMARILY NORTHERN PORTIONS OF
THE FA TUESDAY EVENING.
A STRONGER SYSTEM APPROACHES THE REGION WEDNESDAY EVENING AND MOVES
THROUGH THE AREA WEDNESDAY NIGHT INTO THURSDAY MORNING. ALTHOUGH
THERE HAS BEEN SOME INCONSISTENCIES WITH THE MODELS WITH THIS SYSTEM
THE PAST COUPLE OF DAYS THERE IS ENOUGH CONFIDENCE TO INCREASE
PRECIPITATION CHANCES TO THE UPPER CHANCE CATEGORY. HIGH PRESSURE
WILL THEN MOVE INTO THE REGION FOR THE REMAINDER OF THE LONG TERM.
HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S THROUGH THE LONG TERM
WITH LOW TEMPERATURES IN THE 60S.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS AND THUNDERSTORMS FROM EARLIER THIS MORNING HAVE COME TO
AN END ACROSS THE AREA WITH ONLY SOME LIGHT STRATIFORM RAIN
REMAINING IN PLACES. THERE IS ALSO SOME LIGHT PATCHY FOG AT SOME
OF THE TERMINALS THIS MORNING WHICH SHOULD BURN OFF RATHER QUICKLY
THIS MORNING AS THE SUN COMES UP. THE MAIN CONCERN FOR THE TAF
ISSUANCE REMAINS WHETHER OR NOT THUNDERSTORMS WILL DEVELOP THIS
AFTERNOON OR NOT. WHERE MODELS FIRE THUNDERSTORMS THIS AFTERNOON
IS ALONG THE LEFT OVER BOUNDARY FROM THIS MORNINGS CONVECTION. THE
BOUNDARY IS CURRENTLY JUST WEST OF INTERSTATE 71 AND IS SLIGHTLY
WEAKER THAN WHAT HIGH RES IS CURRENTLY SHOWING. THE BEST CHANCE OF
THUNDER CURRENTLY LOOKS TO BE AT KILN/ KCMH/ AND KLCK.
AS THE SUNSETS EXPECT COVERAGE TO QUICKLY DECREASE WITH WINDS
GOING CALM. CALM WINDS AND A LOW DEWPOINT TEMPERATURE SPREAD WILL
AGAIN BRING THE CHANCE OF REDUCED VISIBILITIES BACK TO THE
TERMINALS. MOSTLY MVFR CIGS SHOULD BE EXPECTED SUNDAY MORNING WITH
IFR AT KLUK.
OUTLOOK...MVFR TO IFR VISIBILITIES POSSIBLE LATE SUNDAY NIGHT AND
EARLY MONDAY MORNING. THUNDERSTORMS POSSIBLE WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...NOVAK
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
413 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE SYSTEM WILL RESULT IN A CHANCE FOR
A FEW THUNDERSTORMS TODAY AND SUNDAY. TEMPERATURES WILL BE
SLIGHTLY ABOVE NORMAL WITH AFTERNOON HIGHS IN THE MID TO UPPER 80S
THROUGH THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A DECAYING MCS IS SAGGING VERY SLOWLY SOUTHWARD ACROSS NORTHWEST
PORTIONS OF OUR FA EARLY THIS MORNING. EXPECT THE PCPN INTENSITY
AND COVERAGE TO CONTINUE TO DECREASE THROUGH DAYBREAK AS IT
PUSHES INTO A MORE STABLE AIRMASS ACROSS SOUTHERN PORTIONS OF OUR
FA.
ASSUMING THE CLOUDS FROM THE MCS DISSIPATE THROUGH THE LATE
MORNING HOURS...WE SHOULD BE ABLE TO DESTABILIZE ONCE AGAIN
THROUGH THIS AFTERNOON. THE NAM MAY BE OVERDONE WITH ITS
INSTABILITY BUT EVEN THE GFS AND RAP ARE INDICATING ML CAPES
PUSHING INTO THE 1500-2000 J/KG RANGE THIS AFTERNOON ACROSS ABOUT
THE NORTHWEST HALF OF OUR FA...DECREASING TO AROUND 1000 J/KG
ACROSS OUR SOUTHEAST. A WEAK UPPER LEVEL LOW ALONG WITH A SHEARED
OUT VORT AXIS IS FORECAST TO SAG SLOWLY SOUTHWEST ACROSS THE AREA
THROUGH THE AFTERNOON. THE COMBINATION OF THIS AND SOME POSSIBLE
LINGERING BOUNDARIES FROM THE CURRENT DECAYING MCS...MAY BE ENOUGH
TO PRODUCE SOME ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPMENT
THIS AFTERNOON. FORECAST SOUNDINGS ARE SHOWING VERY LIGHT WIND
FLOW ALL THE WAY UP TO 300 MB THIS AFTERNOON SO WOULD EXPECT
STORMS TO BE FAIRLY PULSY AND SLOW MOVING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
THE UPPER LEVEL LOW WILL RETROGRADE SLOWLY SOUTHWEST THROUGH THE
DAY ON SUNDAY BEFORE BEGINNING TO WORK BACK TO THE EAST SUNDAY
NIGHT INTO MONDAY. FORCING WILL BE WEAK...BUT AS WE DESTABILIZE
THROUGH THE AFTERNOON...IT WILL BE TOUGH TO RULE OUT A FEW
SHOWERS AND THUNDERSTORMS BOTH SUNDAY AND MONDAY. WILL LIMIT POPS
TO JUST 20-30 PERCENT WITH THE BEST CHANCE IN THE DIURNALLY
FAVORABLE AFTERNOON TO EARLY EVENING. HIGH TEMPERATURES WILL
REMAIN SLIGHTLY ABOVE NORMAL...PUSHING INTO THE MID TO UPPER 80S
BOTH DAYS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ANOTHER DISTURBANCE MOVES ACROSS PRIMARILY NORTHERN PORTIONS OF
THE FA TUESDAY EVENING.
A STRONGER SYSTEM APPROACHES THE REGION WEDNESDAY EVENING AND MOVES
THROUGH THE AREA WEDNESDAY NIGHT INTO THURSDAY MORNING. ALTHOUGH
THERE HAS BEEN SOME INCONSISTENCIES WITH THE MODELS WITH THIS SYSTEM
THE PAST COUPLE OF DAYS THERE IS ENOUGH CONFIDENCE TO INCREASE
PRECIPITATION CHANCES TO THE UPPER CHANCE CATEGORY. HIGH PRESSURE
WILL THEN MOVE INTO THE REGION FOR THE REMAINDER OF THE LONG TERM.
HIGH TEMPERATURES WILL GENERALLY BE IN THE 80S THROUGH THE LONG TERM
WITH LOW TEMPERATURES IN THE 60S.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
CONVECTION CURRENTLY ONGOING ACROSS THE NORTHERN PARTS OF THE CWA
THIS MORNING. THE LINE HAS CONTINUED TO SLOW AND WEAKEN AS IT
PUSHES SOUTH BUT STILL SHOWS SIGNS OF NEW STORM GENERATION OUT IN
FRONT. THERE IS A THREAT FOR SOME OF THE STORMS TO MAKE IT TO
KDAY/ KCMH/ AND KLCK IN THE NEXT COUPLE OF HOURS BEFORE FIZZLING
OUT.
THIS AFTERNOON THE LEFTOVER BOUNDARY FROM THIS MORNINGS CONVECTION
ALONG WITH AN UPPER LEVEL DISTURBANCE WILL ALLOW STORMS TO
REDEVELOP. FORECAST SOUNDINGS SHOW AMPLE INSTABILITY WITH K INDEX
VALUES IS THE UPPER 30S. THE GREATEST CHANCE OF THUNDER APPEARS TO
BE NORTH OF KCVG AND KLUK CLOSER TO THE BOUNDARY. GIVEN THE
UNCERTAINTY HAVE ADDED THUNDER TO ALL TAF SITES. COVERAGE SHOULD
THEN DECREASE AS THE SUN GOES DOWN AND DAY TIME HEATING IS LOST.
OUTLOOK...MVFR TO IFR VISIBILITIES POSSIBLE LATE SUNDAY NIGHT AND
EARLY MONDAY MORNING. THUNDERSTORMS POSSIBLE WEDNESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...JGL
NEAR TERM...JGL
SHORT TERM...JGL
LONG TERM...NOVAK
AVIATION...HAINES
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
533 PM EDT SAT AUG 15 2015
.SYNOPSIS...
A STRENGTHENING RIDGE WILL DEVELOP OVER THE GREAT LAKES AND
NORTHEASTERN UNITED STATES OVER THE NEXT SEVERAL DAYS. THIS WILL
BRING AN EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES THAT WILL
EXTEND THROUGH MUCH OF THE UPCOMING WEEK. MORE UNSETTLED AND
SHOWERY WEATHER RETURNS NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
ELONGATED UPPER SHEAR AXIS DROPPING SOUTHWARD THROUGH THE EASTERN
GLAKS AND FINGERLAKES AND IS INITIATING AND MAINTAINING SCT-NMRS
SHRA AND TSRA ACROSS SOUTHERN NEW YORK STATE NORTH CENTRAL PA
EARLY THIS EVENING. EXPECT ACTIVITY TO PEAK SHORTLY BEFORE SLOWLY
DISSIPATING BY MID TO LATE EVENING AS BUILDING RIDGE CAPS THINGS
OFF.
TEMPS INTO THE 80S TO AROUND 90F IN THE SE WILL FALL BACK TO
GENERALLY THE LOWER TO MID 60S AS HUMIDITY BEGINS TO SLOWLY
INCREASE FROM THE WEST.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
THE UPPER RIDGE WILL DOMINATE SUNDAY GIVING US A VERY WARM DAY
WITH JUST A MINIMAL CHANCE FOR A STRAY SHOWER OR THUNDERSTORM.
BEST CHANCES LOOK TO BE OVER THE NORTH AGAIN...AND WENT WITH LOW
POPS THERE IN HEAT OF THE DAY. HIGHS SOLIDLY IN THE 80S
EVERYWHERE...WILL APPROACH 90 OVER SERN AREAS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
OVERALL RIDGING WILL BUILD INTO THE EASTERN U.S. THROUGH THE
EXTENDED FORECAST...KEEPING THE WARMTH AND HUMIDITY GOING FOR
SEVERAL DAYS.
A WEAKENING FRONTAL BOUNDARY WILL CROSS THE REGION LATE MONDAY AND
TUESDAY WITH SHOWERS AND THUNDERSTORMS. UPPER LEVEL RIDGING WILL
MOVE BACK IN ON ITS HEELS FOR MID WEEK.
THE REST OF THE WEEK LOOKS WARM...WITH THE POSSIBILITY OF ANOTHER
WEAKENING COLD FRONT BRINGING THE NEXT BEST CHANCE FOR RAIN BY
THE END OF THE WEEK.
DAILY HIGHS WILL AVERAGE WELL ABOVE NORMAL FOR THROUGHOUT THE
PERIOD.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
A TROUGH OF LOW PRES TRACKING ACROSS UPSTATE NY WILL PRODUCE SCT
TSRA OVR NORTHERN PA THRU ARND SUNSET THIS EVENING. RADAR TRENDS
AND HRRR OUTPUT WOULD SUGGEST A BRIEF VIS REDUCTION REMAINS POSS
AT KBFD THRU ARND 00Z AND AT KIPT BTWN 23Z-01Z.
EARLY EVENING TSRA SHOULD DIE WITH LOSS OF HEATING AFTER SUNSET.
FOCUS WILL THEN SHIFT TOWARD LATE NIGHT FOG. CLEARING SKIES...A
CALM WIND AND WET GROUND SHOULD PROMOTE PATCHY DENSE FOG IN THE
VALLEYS OF NORTHERN PA BTWN 04Z-12Z. KBFD APPEARS LIKELY TO
EXPERIENCE A PERIOD OF IFR/LIFR VSBYS SOMETIME BTWN 04Z-12Z.
KIPT COULD POTENTIALLY EXPERIENCE IFR CONDS EARLY SUN AM IF RAIN
FALLS THERE THIS EVENING. ACROSS SOUTHERN PA...NOTHING MORE THAN A
BRIEF PERIOD OF LIGHT /MVFR/ FOG EXPECTED ARND SUNRISE.
A RIDGE OF HIGH PRESSURE WILL OVERSPREAD THE AREA FROM THE MIDWEST
ON SUNDAY...ENSURING WIDESPREAD VFR CONDS AND LIGHT WIND.
OUTLOOK...
MON...NO SIG WX EXPECTED. ISO TSTMS WEST.
TUE-THU...ISO/SCT TSRA IMPACTS.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RXR
NEAR TERM...DEVOIR/RXR
SHORT TERM...RXR
LONG TERM...LA CORTE/TYBURSKI
AVIATION...FITZGERALD/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
730 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A STRENGTHENING RIDGE WILL DEVELOP OVER THE GREAT LAKES AND
NORTHEASTERN UNITED STATES OVER THE NEXT SEVERAL DAYS. THE RIDGE
WILL LEAD TO AN EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES FOR
THE WEEKEND THROUGH THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SLOW MOVING AND WEAK COLD FRONT/LOW LEVEL CONVERGENCE ZONE HAS
SETTLED DOWN OVER LAKE ONTARIO UNDER AN ELONGATED MID LEVEL TROUGH
THAT EXTENDS DOWN INTO INDIANA. THIS LOW LEVEL BOUNDARY SEEMS TO
BE HELPING FOCUS A SMALL BUT SIGNIFICANT MCS IN THE VICINITY OF
BUFFALO WHERE RADAR IS ESTIMATING 5+ INCH RAINFALL AMOUNTS. THE
RADAR LOOKS NOT UNLIKE A GOOD LAKE EFFECT SNOW EVENT GIVEN HOW THE
STORMS SEEM ANCHORED TO THE LAKE SHORE AND KEEP TRAINING OVER THE
SAME AREA.
THE FUTURE OF THIS BOUNDARY/UPPER SHEAR ZONE COULD PLAY A ROLE IN
THE WEATHER FOR OUR NORTHERN COUNTIES AS THE SYNOPTIC SCALE
MODELS HINT THAT THEY WILL SLIDE INTO SOUTHERN NY/NRN PA LATER
TODAY OR OVERNIGHT. THE MODELS...WHICH HAVE NOT HANDLED THE
SYSTEM WELL...ALSO SHOW IT WEAKENING AS THE UPPER SHEAR ZONE
YIELDS TO THE RIDGE THAT IS MADE TO BUILD IN STRONGLY FROM THE MID
WEST AND GR LAKES.
FOR TODAY THE MAIN THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE
MAINLY NORTH OF I80 ASSOCIATED WITH THE UPPER SHEAR ZONE AND WEAK
LOW LEVEL BOUNDARY. 00Z OPERATIONAL MODELS ALL DEVELOP A
RESPECTABLE AMOUNT OF CAPE BY AFTERNOON. THE GEFS SHOWS THE BEST
CAPE FAVORING NWRN PA WHILE THE SREF IS MORE UNSTABLE OVER A
BROADER AREA OF NRN AND NWRN PA. BY 18Z/2PM LOCAL THE HRRR SHOWS A
DEVELOPING AREA OF CONVECTION FROM SRN NY BACK INTO NW PA. NO
REASON TO THINK THIS WILL NOT DEVELOP FURTHER AND CONTINUE
SOUTHEAST INTO THE NRN MOUNTAINS.
I DROPPED POPS THIS EVENING AND OVERNIGHT USING THE BUILDING RIDGE
AS A BELIEVABLE REASON TO PUT A LID ON WHATEVER CONVECTION MANAGES
TO FORM LATER TODAY.
IT WILL BE ANOTHER WARM DAY WITH HIGHS GENERALLY IN THE LOW TO MID
80S. DEWPOINTS WHICH HAVE BEEN KEPT AT BAY WILL BEGIN TO CREEP
SLOWLY UPWARD UNDER THE BUILDING RIDGE. DOESN`T LOOK LIKE IT WILL
BE OPPRESSIVELY HUMID...BUT NOT QUITE AS COMFORTABLE AS IT HAS
BEEN ON RECENT DAYS.
&&
.SHORT TERM /SUNDAY/...
THE UPPER RIDGE WILL DOMINATE SUNDAY GIVING US A VERY WARM DAY
WITH JUST A MINIMAL CHANCE FOR A STRAY SHOWER OR THUNDERSTORM
WHICH I CHOSE TO NOT INCLUDE IN THE FORECAST. HIGHS IN THE 80S
EVERYWHERE...WILL APPROACH 90 OVER SERN AREAS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE PATTERN OVER THE EASTERN US WILL FAVOR A MEAN RIDGE AND WHAT
LOOKS LIKE SEVERAL DAYS OF SUMMER WARMTH AND HUMIDITY.
THINGS GET A LITTLE MESSY LATER MONDAY INTO TUESDAY AS WHAT`S LEFT
OF A SHORTWAVE AND SURFACE FRONT MOVE INTO THE EASTERN GR LAKES
AND EVENTUALLY THE NERN US. OPERATIONAL GFS/ECMWF NOW PRETTY MUCH
WASH THE FRONT...BUT USE THE WEAK UPPER TROUGH TO INCREASE
MOISTURE AND TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS...WITH
TUESDAY LOOKING LIKE IT WILL BE THE BEST DAY FOR RAIN CHANCES.
THE REST OF THE WEEK LOOKS WARM...WITH THE POSSIBILITY OF A DYING
COLD FRONT BRINGING THE NEXT BEST CHANCE FOR RAIN BY THE END OF
THE WEEK.
DAILY HIGHS WILL AVERAGE WELL ABOVE NORMAL FOR THROUGHOUT THE
PERIOD.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
ADJUSTED THE 12Z TAF PACKAGE FOR A FEW SPOTS THAT HAVE SOME
FOG.
ALSO ADDED IN SOME FOG FOR LATE TONIGHT AGAIN.
EARLIER DISCUSSION BELOW.
CONVECTION OFF LAKE ERIE A LITTLE WEAKER NOW...ACTING A LOT
LIKE THE EVENT WE HAD BACK LAST NOVEMBER...WHEN WE HAD RECORD
COLD AIR EARLY IN THE SEASON AND SNOW SQUAALS.
A WEAK WIND SHIFT LINE TO THE NORTH HAS RESULTED IN SHOWERS AND
THUNDERSTORMS...AS THE FLOW OF AIR OFF THE LAKES HAS RESULTED IN
HIGHER DEWPOINTS.
FOR THE 06Z TAF PACKAGE...HAVE VCSH IN BFD LATE TODAY...BEHIND
WIND SHIFT LINE. LEFT MENTION OF SHOWERS OUT OF OTHER SITES FOR
NOW. PATTERN IS RATHER COMPLEX. SOME MODELS WANT TO BUILD AN
OMEGA BLOCK ACROSS NY AND PA.
OUTLOOK...
SUN...PATCHY AM FOG POSS N MTNS.
MON...NO SIG WX EXPECTED.
TUE-WED...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
521 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A STRENGTHENING RIDGE WILL DEVELOP OVER THE GREAT LAKES AND
NORTHEASTERN UNITED STATES OVER THE NEXT SEVERAL DAYS. THE RIDGE
WILL LEAD TO AN EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES FOR
THE WEEKEND THROUGH THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SLOW MOVING AND WEAK COLD FRONT/LOW LEVEL CONVERGENCE ZONE HAS
SETTLED DOWN OVER LAKE ONTARIO UNDER AN ELONGATED MID LEVEL TROUGH
THAT EXTENDS DOWN INTO INDIANA. THIS LOW LEVEL BOUNDARY SEEMS TO
BE HELPING FOCUS A SMALL BUT SIGNIFICANT MCS IN THE VICINITY OF
BUFFALO WHERE RADAR IS ESTIMATING 5+ INCH RAINFALL AMOUNTS. THE
RADAR LOOKS NOT UNLIKE A GOOD LAKE EFFECT SNOW EVENT GIVEN HOW THE
STORMS SEEM ANCHORED TO THE LAKE SHORE AND KEEP TRAINING OVER THE
SAME AREA.
THE FUTURE OF THIS BOUNDARY/UPPER SHEAR ZONE COULD PLAY A ROLE IN
THE WEATHER FOR OUR NORTHERN COUNTIES AS THE SYNOPTIC SCALE
MODELS HINT THAT THEY WILL SLIDE INTO SOUTHERN NY/NRN PA LATER
TODAY OR OVERNIGHT. THE MODELS...WHICH HAVE NOT HANDLED THE
SYSTEM WELL...ALSO SHOW IT WEAKENING AS THE UPPER SHEAR ZONE
YIELDS TO THE RIDGE THAT IS MADE TO BUILD IN STRONGLY FROM THE MID
WEST AND GR LAKES.
FOR TODAY THE MAIN THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE
MAINLY NORTH OF I80 ASSOCIATED WITH THE UPPER SHEAR ZONE AND WEAK
LOW LEVEL BOUNDARY. 00Z OPERATIONAL MODELS ALL DEVELOP A
RESPECTABLE AMOUNT OF CAPE BY AFTERNOON. THE GEFS SHOWS THE BEST
CAPE FAVORING NWRN PA WHILE THE SREF IS MORE UNSTABLE OVER A
BROADER AREA OF NRN AND NWRN PA. BY 18Z/2PM LOCAL THE HRRR SHOWS A
DEVELOPING AREA OF CONVECTION FROM SRN NY BACK INTO NW PA. NO
REASON TO THINK THIS WILL NOT DEVELOP FURTHER AND CONTINUE
SOUTHEAST INTO THE NRN MOUNTAINS.
I DROPPED POPS THIS EVENING AND OVERNIGHT USING THE BUILDING RIDGE
AS A BELIEVABLE REASON TO PUT A LID ON WHATEVER CONVECTION MANAGES
TO FORM LATER TODAY.
IT WILL BE ANOTHER WARM DAY WITH HIGHS GENERALLY IN THE LOW TO MID
80S. DEWPOINTS WHICH HAVE BEEN KEPT AT BAY WILL BEGIN TO CREEP
SLOWLY UPWARD UNDER THE BUILDING RIDGE. DOESN`T LOOK LIKE IT WILL
BE OPPRESSIVELY HUMID...BUT NOT QUITE AS COMFORTABLE AS IT HAS
BEEN ON RECENT DAYS.
&&
.SHORT TERM /SUNDAY/...
THE UPPER RIDGE WILL DOMINATE SUNDAY GIVING US A VERY WARM DAY
WITH JUST A MINIMAL CHANCE FOR A STRAY SHOWER OR THUNDERSTORM
WHICH I CHOSE TO NOT INCLUDE IN THE FORECAST. HIGHS IN THE 80S
EVERYWHERE...WILL APPROACH 90 OVER SERN AREAS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE PATTERN OVER THE EASTERN US WILL FAVOR A MEAN RIDGE AND WHAT
LOOKS LIKE SEVERAL DAYS OF SUMMER WARMTH AND HUMIDITY.
THINGS GET A LITTLE MESSY LATER MONDAY INTO TUESDAY AS WHAT`S LEFT
OF A SHORTWAVE AND SURFACE FRONT MOVE INTO THE EASTERN GR LAKES
AND EVENTUALLY THE NERN US. OPERATIONAL GFS/ECMWF NOW PRETTY MUCH
WASH THE FRONT...BUT USE THE WEAK UPPER TROUGH TO INCREASE
MOISTURE AND TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS...WITH
TUESDAY LOOKING LIKE IT WILL BE THE BEST DAY FOR RAIN CHANCES.
THE REST OF THE WEEK LOOKS WARM...WITH THE POSSIBILITY OF A DYING
COLD FRONT BRINGING THE NEXT BEST CHANCE FOR RAIN BY THE END OF
THE WEEK.
DAILY HIGHS WILL AVERAGE WELL ABOVE NORMAL FOR THROUGHOUT THE
PERIOD.
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
NO REAL CHANGE FOR THE 09Z TAF PACKAGE.
CONVECTION OFF LAKE ERIE A LITTLE WEAKER NOW...ACTING A LOT
LIKE THE EVENT WE HAD BACK LAST NOVEMBER...WHEN WE HAD RECORD
COLD AIR EARLY IN THE SEASON AND SNOW SQUAALS. .
EARLIER DISCUSSION BELOW.
A WEAK WIND SHIFT LINE TO THE NORTH HAS RESULTED IN SHOWERS
AND THUNDERSTORMS...AS THE FLOW OF AIR OFF THE LAKES HAS
RESULTED IN HIGHER DEWPOINTS.
FOR THE 06Z TAF PACKAGE...HAVE VCSH IN BFD LATE TODAY...BEHIND
WIND SHIFT LINE. LEFT MENTION OF SHOWERS OUT OF OTHER SITES FOR
NOW. PATTERN IS RATHER COMPLEX. SOME MODELS WANT TO BUILD AN
OMEGA BLOCK ACROSS NY AND PA.
OUTLOOK...
SUN...PATCHY AM FOG POSS N MTNS.
MON...NO SIG WX EXPECTED.
TUE-WED...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
451 AM EDT SAT AUG 15 2015
.SYNOPSIS...
A STRENGTHENING RIDGE WILL DEVELOP OVER THE GREAT LAKES AND
NORTHEASTERN UNITED STATES OVER THE NEXT SEVERAL DAYS. THE RIDGE
WILL LEAD TO AN EXTENDED PERIOD OF ABOVE NORMAL TEMPERATURES FOR
THE WEEKEND THROUGH THE UPCOMING WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A SLOW MOVING AND WEAK COLD FRONT/LOW LEVEL CONVERGENCE ZONE HAS
SETTLED DOWN OVER LAKE ONTARIO UNDER AN ELONGATED MID LEVEL TROUGH
THAT EXTENDS DOWN INTO INDIANA. THIS LOW LEVEL BOUNDARY SEEMS TO
BE HELPING FOCUS A SMALL BUT SIGNIFICANT MCS IN THE VICINITY OF
BUFFALO WHERE RADAR IS ESTIMATING 5+ INCH RAINFALL AMOUNTS. THE
RADAR LOOKS NOT UNLIKE A GOOD LAKE EFFECT SNOW EVENT GIVEN HOW THE
STORMS SEEM ANCHORED TO THE LAKE SHORE AND KEEP TRAINING OVER THE
SAME AREA.
THE FUTURE OF THIS BOUNDARY/UPPER SHEAR ZONE COULD PLAY A ROLE IN
THE WEATHER FOR OUR NORTHERN COUNTIES AS THE SYNOPTIC SCALE
MODELS HINT THAT THEY WILL SLIDE INTO SOUTHERN NY/NRN PA LATER
TODAY OR OVERNIGHT. THE MODELS...WHICH HAVE NOT HANDLED THE
SYSTEM WELL...ALSO SHOW IT WEAKENING AS THE UPPER SHEAR ZONE
YIELDS TO THE RIDGE THAT IS MADE TO BUILD IN STRONGLY FROM THE MID
WEST AND GR LAKES.
FOR TODAY THE MAIN THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE
MAINLY NORTH OF I80 ASSOCIATED WITH THE UPPER SHEAR ZONE AND WEAK
LOW LEVEL BOUNDARY. 00Z OPERATIONAL MODELS ALL DEVELOP A
RESPECTABLE AMOUNT OF CAPE BY AFTERNOON. THE GEFS SHOWS THE BEST
CAPE FAVORING NWRN PA WHILE THE SREF IS MORE UNSTABLE OVER A
BROADER AREA OF NRN AND NWRN PA. BY 18Z/2PM LOCAL THE HRRR SHOWS A
DEVELOPING AREA OF CONVECTION FROM SRN NY BACK INTO NW PA. NO
REASON TO THINK THIS WILL NOT DEVELOP FURTHER AND CONTINUE
SOUTHEAST INTO THE NRN MOUNTAINS.
I DROPPED POPS THIS EVENING AND OVERNIGHT USING THE BUILDING RIDGE
AS A BELIEVABLE REASON TO PUT A LID ON WHATEVER CONVECTION MANAGES
TO FORM LATER TODAY.
IT WILL BE ANOTHER WARM DAY WITH HIGHS GENERALLY IN THE LOW TO MID
80S. DEWPOINTS WHICH HAVE BEEN KEPT AT BAY WILL BEGIN TO CREEP
SLOWLY UPWARD UNDER THE BUILDING RIDGE. DOESN`T LOOK LIKE IT WILL
BE OPPRESSIVELY HUMID...BUT NOT QUITE AS COMFORTABLE AS IT HAS
BEEN ON RECENT DAYS.
&&
.SHORT TERM /SUNDAY/...
THE UPPER RIDGE WILL DOMINATE SUNDAY GIVING US A VERY WARM DAY
WITH JUST A MINIMAL CHANCE FOR A STRAY SHOWER OR THUNDERSTORM
WHICH I CHOSE TO NOT INCLUDE IN THE FORECAST. HIGHS IN THE 80S
EVERYWHERE...WILL APPROACH 90 OVER SERN AREAS.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THE PATTERN OVER THE EASTERN US WILL FAVOR A MEAN RIDGE AND WHAT
LOOKS LIKE SEVERAL DAYS OF SUMMER WARMTH AND HUMIDITY.
THINGS GET A LITTLE MESSY LATER MONDAY INTO TUESDAY AS WHAT`S LEFT
OF A SHORTWAVE AND SURFACE FRONT MOVE INTO THE EASTERN GR LAKES
AND EVENTUALLY THE NERN US. OPERATIONAL GFS/ECMWF NOW PRETTY MUCH
WASH THE FRONT...BUT USE THE WEAK UPPER TROUGH TO INCREASE
MOISTURE AND TRIGGER SCATTERED SHOWERS AND THUNDERSTORMS...WITH
TUESDAY LOOKING LIKE IT WILL BE THE BEST DAY FOR RAIN CHANCES.
THE REST OF THE WEEK LOOKS WARM...WITH THE POSSIBILITY OF A DYING
COLD FRONT BRINGING THE NEXT BEST CHANCE FOR RAIN BY THE END OF
THE WEEK.
DAILY HIGHS WILL AVERAGE WELL ABOVE NORMAL FOR THROUGHOUT THE
PERIOD.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
A WEAK WIND SHIFT LINE TO THE NORTH HAS RESULTED IN SHOWERS
AND THUNDERSTORMS...AS THE FLOW OF AIR OFF THE LAKES HAS
RESULTED IN HIGHER DEWPOINTS.
FOR THE 06Z TAF PACKAGE...HAVE VCSH IN BFD LATE TODAY...BEHIND
WIND SHIFT LINE. LEFT MENTION OF SHOWERS OUT OF OTHER SITES FOR
NOW. PATTERN IS RATHER COMPLEX. SOME MODELS WANT TO BUILD AN
OMEGA BLOCK ACROSS NY AND PA.
OUTLOOK...
SUN...PATCHY AM FOG POSS N MTNS.
MON...NO SIG WX EXPECTED.
TUE-WED...ISOLD PM TSRA IMPACTS POSSIBLE.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LA CORTE
NEAR TERM...LA CORTE
SHORT TERM...LA CORTE
LONG TERM...LA CORTE
AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
847 PM CDT SUN AUG 16 2015
.EVENING UPDATE...
CONVECTION HAS SINCE WANED ACROSS MIDDLE TN AND WEAKENED FURTHER
SOUTH ACROSS ALABAMA. THE UPPER LOW OVERHEAD WILL RETROGRADE A
LITTLE TO THE NORTHWEST THROUGH TOMORROW...SO MOISTURE SHOULD
STILL DRAW NORTHWARD OVERNIGHT. WILL INCREASE SLIGHT-LOW CHC POPS
THROUGH DAWN FROM THE SOUTH TO THE NORTH. THE LATEST HRRR AND NAM
GENERATE QUITE A BIT OF PRECIP AROUND 12Z SO WILL TREND THAT WAY.
WILL INCLUDE LIGHT FOG OVER NNERN AREAS AS WELL.
TEMPS LOOK ON TRACK FOR THE MOST PART. TRENDED A TAD WARMER WITH
CLOUDS INCREASING FROM THE SOUTH THOUGH.
NO OTHER CHANGES MADE. UPDATE OUT SHORTLY.
&&
.PREV DISCUSSION... /ISSUED 653 PM CDT SUN AUG 16 2015/
AVIATION UPDATE...
FOR 00Z AVIATION.
CONDITIONS SHOULD MAINLY BE VFR...WITH CHANCES FOR FOG AGAIN AT
KCKV AND KCSV TONIGHT. MODELS AGAIN WANT TO PLACE MVFR/IFR FOG
OVER KCKV AND KCSV...WITH A FEW MODELS SUGGESTING EVEN LIFR FOG
SIMILAR TO LAST NIGHT. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL
REMAIN DURING THE ENTIRE TAF PERIOD...WITH BETTER CHANCES DURING
THE MORNING AND AFTERNOON ON MONDAY. CIGS SHOULD REMAIN VFR.
PREV DISCUSSION... /ISSUED 306 PM CDT SUN AUG 16 2015/
DISCUSSION...
CONVECTION THIS AFTERNOON CONCENTRATED ACROSS THE SOUTH AND ALONG
THE PLATEAU WITH MOSTLY ISOLATED CONVECTION OVER THE NORTH. UPPER
LOW AND ASSOCIATED COOL POOL SPINNING ABOUT A CENTER OVER FAR
WESTERN KENTUCKY. GOOD MOISTURE FEED INTO MIDDLE TENNESSEE FROM
GULF REGION AS SURFACE BERMUDA RIDGE LAYS ACROSS EASTERN U.S. AND
MID STATE ON SOUTH SIDE OF RIDGE AXIS. UPPER LOW WILL REMAIN
INSITU AS WEAK SHORT WAVES WORK NORTHWARD FROM GULF REGION TONIGHT
AND MONDAY. WILL KEEP POPS GOING TONIGHT FOR THE MID STATE WITH
THE HIGHER POPS OVER THE SOUTH AND EAST BUT CONVECTION MAY BE
SKIMPY AT TIMES. THERE WILL LIKELY BE SOME POINT THIS EVENING
THAT CONVECTION BEGINS TO DIMINISH ONLY TO BE REJUVENATED BY YET
ANOTHER WEAK SHORT WAVE LIFTING NORTH BOUND FROM ALABAMA. ONE
SLIGHTLY STRONGER SHORT WAVES LIFTS NORTH FROM ALABAMA AFTER
MIDNIGHT AND WILL LIKELY GIN UP CONVECTION OVER SOUTHEASTERN AREAS
AND ALONG THE SOUTH END OF THE PLATEAU AFTER 06Z. HARD TO TIME
THESE FEATURES AND JUST HOW MUCH DIURNAL TRENDS WILL COME INTO
PLAY IN KILLING OFF CONVECTION IN THE MID STATE THIS EVENING
IS DIFFICULT TO SAY.
BROAD UPPER TROUGH DOMINATES EASTERN U.S THIS WEEK AS A SERIES OF
DISTURBANCES TRAVERSE THROUGH SO AM KEEPING SHOWER AND TSTORM
CHANCES IN THE FORECAST PRETTY MUCH FOR EACH PERIOD. RATHER
VIGOROUS SHORT WAVE MOVES ACROSS OUR AREA WEDNESDAY AND WEDNESDAY
NIGHT THAT COULD PRODUCE A FEW STRONG TO POSSIBLY SEVERE STORMS
HERE IN THE MID STATE.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AL
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
636 PM CDT SUN AUG 16 2015
.UPDATE...
UPDATED TO INCREASED POPS OVER NORTHEAST MISSISSIPPI THROUGH EARLY
EVENING.
&&
.DISCUSSION...
CONVECTIVE OUTFLOW CONTINUES TO PUSH NORTH AND WEST ACROSS NORTH
MISSISSIPPI LATE THIS AFTERNOON...WITH A FEW EMBEDDED STRONG
STORMS CAPABLE OF 40 MPH WIND GUSTS AND SMALL HAIL. THE HEAVIEST
ACTIVITY WILL CONTINUE TO SURGE NORTHWARD THROUGH 8PM THIS
EVENING INTO PORTIONS OF SOUTHWEST TENNESSEE BEFORE STRATIFYING.
HAVE INCREASED POPS IN THIS REGION ACCORDINGLY. AN ISOLATED SHOWER
OR STORM WILL REMAIN POSSIBLE OVER THE MIDSOUTH TONIGHT...ESPECIALLY
IN THE EAST...AS ANOTHER SHORTWAVE LIFTS NORTH FROM THE GULF
COAST.
JAB
&&
.PREV DISCUSSION... /ISSUED 351 PM CDT SUN AUG 16 2015/
DISCUSSION...
MAIN FORECAST CONCERNS REVOLVE AROUND POWERFUL MID-LATITUDE
DISTURBANCE FORECAST TO IMPACT MUCH OF THE MID-SOUTH ON WEDNESDAY.
LEADING UP TO WEDNESDAY...AFTERNOON STORMS ARE EXPECTED DAILY...
CURRENTLY...THE PERSISTENT BUT WEAK UPPER LEVEL LOW IS STILL
MEANDERING JUST NORTHEAST OF THE MID-SOUTH THIS AFTERNOON. CURRENT
RADAR MOSAIC IS NEARLY IDENTICAL TO YESTERDAY/S WITH AN OUTFLOW
BOUNDARY APPROACHING THE MEMPHIS METRO FROM THE EAST WITH
SCATTERED THUNDERSTORMS ALONG IT. STORM MOTION IS MORE
NORTHWESTERLY THAN WESTERLY AS COMPARED TO YESTERDAY.
IN THE NEAR-TERM...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS
SHOULD PERSIST THROUGH THE DURATION OF THE AFTERNOON DURING PEAK
HEATING. FOR TONIGHT...FORECAST SOUNDINGS INDICATE THAT A BAND OF
STRATUS/STRATIFORM LIGHT PRECIP WITH EMBEDDED THUNDER WILL DEVELOP
AFTER MIDNIGHT MAINLY ALONG THE TENNESSEE RIVER VALLEY. THIS LOOKS
TO BE ASSOCIATED WITH SLOW VERTICAL ASCENT WITHIN THE DIFFUSE WARM
CONVEYOR BELT OF THE UPPER LEVEL LOW. IF THIS SCENARIO UNFOLDS AS
FORECAST...HIGH TEMPERATURES MAY NEED TO BE LOWERED TOMORROW GIVEN
WIDESPREAD CLOUDINESS AND POTENTIAL PRECIP. ALREADY LOWERED
FORECAST HIGHS SOMEWHAT ACROSS THE TENNESSEE RIVER VALLEY...BUT
MAY NOT HAVE BEEN SUFFICIENT.
BY LATE MORNING...AREAS THAT DO SEE INSOLATION WILL BECOME
UNSTABLE QUICKLY AND WEAK LIFT ASSOCIATED WITH THE UPPER LOW WILL
BE SUFFICIENT FOR SCATTERED THUNDERSTORM DEVELOPMENT PRIOR TO 18Z.
IT IS HARD TO PIN DOWN EXACTLY WHERE THE GREATEST COVERAGE OF
PRECIP WILL BE TOMORROW...BUT MOST AREAS SHOULD SEE A SHOWER OR
THUNDERSTORM BY MONDAY/S END.
A SIMILAR SURFACE AND UPPER LEVEL PATTERN TO MONDAY WILL EXIST ON
TUESDAY AS WELL. LATE MORNING AND AFTERNOON STORMS ARE ONCE AGAIN
EXPECTED TO DEVELOP IN THE UNCAPPED AIRMASS WELL AHEAD OF A
DEVELOPING UPPER LEVEL TROUGH. CONTINUED THE TREND OF KEEPING
HIGHS COOLER GIVEN EXPECTED WIDESPREAD PRECIP AND CLOUD COVER
LIMITING HEATING.
FOCUS THEN SHIFTS TO WEDNESDAY AND ASSOCIATED SEVERE WEATHER
POTENTIAL. MODELS ARE IN GENERAL AGREEMENT THAT A LARGE-SCALE MEAN
TROUGH AXIS WILL SWEEP THROUGH THE CENTRAL US ON WEDNESDAY. THAT
BEING SAID...IMPORTANT DIFFERENCES DO EXIST WITH REGARD TO
PLACEMENT OF SURFACE FEATURES AND GENERAL EVOLUTION THE EVENT.
FOCUSING ON THE SYNOPTIC SETUP AND ANOMALOUS DEPTH OF THE
TROUGH FOR MID-AUGUST...ISOLATED SEVERE WEATHER SEEMS PROBABLE
WITH THE POTENTIAL FOR A WIDESPREAD EVENT STILL UNCERTAIN. THE
MOST FAVORABLE KINEMATICS WILL ALMOST CERTAINLY BE NORTH OF THE
MID-SOUTH...BUT THE NAM SUGGESTS THAT A SUBTLE LEAD IMPULSE AND
ASSOCIATED JET MAX AHEAD OF THE MEAN TROUGH WILL ROTATE THROUGH
THE MID-SOUTH. THIS SOLUTION WOULD INCREASE SEVERE WEATHER
POTENTIAL ACROSS THE REGION WITH DEEP LAYER SHEAR MUCH MORE
FAVORABLE FOR ORGANIZED CONVECTION AS COMPARED TO THE OTHER GLOBAL
MODEL SOLUTIONS. AS OF NOW...THE NAM IS THE OUTLIER WITH THIS
SOLUTION BUT IT SHOULD NOT BE DISCOUNTED AS OF YET. THERMODYNAMICS
WILL BE FAVORABLE WITH A BUOYANT WARM SECTOR AIRMASS IN PLACE.
FORECAST SOUNDINGS INDICATED MLCAPE VALUES BETWEEN 1500 - 3000
J/KG...DEPENDING ON LOCATION. DAMAGING WINDS APPEAR TO BE THE MAIN
THREAT AS OF NOW...WITH TORNADIC POTENTIAL LARGELY MITIGATED BY
WEAK/VEERED 0-2KM FLOW. CONTINUED THE TREND OF MAINTAINING LIKELY
PRECIP CHANCES...ESPECIALLY DURING THE AFTERNOON HOURS ON
WEDNESDAY.
FRONTAL PASSAGE LOOKS TO OCCUR SOMETIME WEDNESDAY...BUT IT WILL BE
SLOW TO OCCUR AS UPPER LEVEL FLOW BECOMES MORE AND MORE PARALLEL
TO THE FRONT WITH TIME. THIS WILL LIKELY MAINTAIN PRECIP ALONG AND
SOUTH OF THE I-40 CORRIDOR THROUGH THE END OF THE WEEK.
IN THE LONG-TERM...THINKING REMAINS LARGELY THE SAME. NEAR TO
BELOW NORMAL TEMPERATURES ARE EXPECTED BUT AN ACTIVE NORTHERN
STREAM LOOKS KEEP MUCH OF THE CONUS IN AN ACTIVE WEATHER REGIME
RESEMBLING LATE SPRING MUCH MORE THAN MID-AUGUST.
TVT
&&
.AVIATION...
18Z TAFS
GOES WATER VAPOR SHOWED A COMPACT UPPER LEVEL CIRCULATION CENTERED
NEAR PHT...NEARLY STATIONARY OR PERHAPS DRIVING VERY SLOWLY NORTHWEST.
EXPECT SCT SHRA/TSRA TO REMAIN NORTHEAST OF MKL THROUGH 20Z...
LIKELY EXPANDING TO THE SOUTHWEST THEREAFTER. HRRR APPEARS AT
OVERDONE INITIALLY...W/RESPECT TO TSRA COVERAGE IN THE 18Z TO 19Z
PERIOD.
LIMITED LOW LEVEL CONVERGENCE AND WEAK MIDLEVEL LAPSE RATES SHOULD
KEEP TS CHANCES LOW AT MEM...BUT LIKELY TIED TO CONVECTIVE INITIATION
OVER NORTH MS AND RESULTANT CONVECTIVE OUTFLOW BOUNDARIES.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1231 PM CDT SAT AUG 15 2015
.UPDATE...
UPDATED FOR 18Z AVIATION DISCUSSION BELOW.
&&
.PREV DISCUSSION... /ISSUED 1058 AM CDT SAT AUG 15 2015/
UPDATE...
THE MAIN UPDATE TO THE FORECAST TODAY WAS TO INCREASE PRECIP
CHANCES ESPECIALLY ACROSS PORTIONS OF WEST TN WHERE HI-RES
GUIDANCE SUPPORTS AFTERNOON THUNDERSTORM DEVELOPMENT. CURRENT
SHOWERS/TSTORMS WERE LOCATED ALONG THE TN RIVER DRIFTING SLOWLY
WEST THROUGH THE LATE MORNING. OUTFLOW FROM CURRENT STORMS SHOULD
FORCE NEW DEVELOPMENT IN THE BUOYANT AIRMASS AHEAD OF THE COLD
POOL DURING THE EARLY TO MID AFTERNOON HOURS. THIS ACTIVITY SHOULD
DECREASE IN COVERAGE/INTENSITY THROUGH THE LATE EVENING. ALSO
LOWERED HIGHS WHERE CURRENT CLOUD COVER/PRECIP IS LIMITING
WARMING.
TVT
PREV DISCUSSION... /ISSUED 437 AM CDT SAT AUG 15 2015/
DISCUSSION...
CURRENTLY...
A QUIET MID-AUGUST MORNING THROUGHOUT THE MIDSOUTH WITH LIGHT
SURFACE WINDS FROM THE NORTH AND TEMPERATURES NEAR NORMAL VALUES.
AREA RADARS ARE SHOWING A LINE OF LIGHT RETURNS STRETCHING ACROSS
NORTH MISSISSIPPI JUST SOUTH OF OUR CWA INTO NORTHWEST ALABAMA.
ONE LONE SHOWER EMBEDDED WITHIN THIS LINE HAS HEAVY ENOUGH RETURNS
TO SUGGEST THAT PRECIP MAY BE REACHING THE GROUND AS IT APPROACHES
KGWX AND MONROE COUNTY. ANOTHER ISOLATED SHOWER OR TWO MAY
DEVELOP DURING THE MORNING HOURS OVER NORTHEAST MISSISSIPPI BUT
THE REST OF THE MIDSOUTH WILL REMAIN DRY.
SHORT TERM...
THE PLEASANT WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE
WEEKEND WITH NEAR OR SLIGHTLY BELOW NORMAL TEMPS AND THE MAJORITY
OF THE MIDSOUTH REMAINING DRY. AFTERNOON THUNDERSTORM COVERAGE
WILL BE GREATER TODAY MAINLY IN THE EASTERN PORTIONS OF OUR REGION
AS AN UPPER LEVEL TROUGH CONTINUES TO DIG INTO THE REGION FROM
THE NORTH EAST. THE HRRR KEEPS AFTERNOON CONVECTION WEST OF THE
MS RIVER. THESE DIURNALLY DRIVEN STORMS SHOULD BEGIN TO WANE AS WE
LOSE DAYTIME HEATING. AFTERNOON STORM COVERAGE SHOULD INCREASE
EVEN MORE ON SUNDAY AS THE UPPER LOW MOVES WESTWARD AND LOWER
LEVEL SOUTHERLY FLOW INCREASES PULLING MORE MOISTURE INTO THE
SOUTHEASTERN STATES FROM THE GULF OF MEXICO.
LONG TERM...
HIGH TEMPERATURES WILL BE NEAR 90 DEGREES EACH DAY EARLY NEXT WEEK
WITH LOWS NEAR 70 AND CHANCES OF STORMS EACH EVENING.THE BEST
CHANCES OF AREA WIDE PRECIP DURING THE UPCOMING WEEK WILL BE ON
WEDNESDAY AS MODELS AGREE ON A STRENGTHENING UPPER TROUGH AND
ASSOCIATED SURFACE COLD FRONT MOVING THROUGH THE REGION. SOUTHERLY
FLOW WILL INCREASE AS THIS SYSTEM NEARS INCREASING MOISTURE
THROUGHOUT THE AREA. HEAT INDICES WILL APPROACH 100 DEGREES ON
WEDNESDAY BEFORE THE FRONT MATRICULATES THROUGH THE AREA BRINGING
WITH IT COOLER AIR FOR THURSDAY. MODELS AGREE ON AN UPPER LEVEL
HIGH BUILDING OVER THE SOUTHEASTERN UNITED STATES BY NEXT WEEKEND.
JPM3
&&
.AVIATION...
18Z TAFS
NEARLY STATIONARY UPPER LEVEL TROF AND RETURN OF MODIFIED AND
UNSTABLE GULF AIRMASS WILL RESULT IN CONTINUED SCATTERED TSRA
OVER TN RIVER VALLEY THIS AFTERNOON. THIS ACTIVITY WILL LIKELY
DEVELOP AS FAR WEST AT MKL AND TUP...AND POSSIBLY AS WEST AS
EASTERN PORTIONS OF THE MEM TRACON FOR A BRIEF PERIOD THIS
AFTERNOON. EXPECT A DIURNAL WEAKENING TREND THIS EVENING...WITH
MOST TSRA CONTRACTING BACK TO THE EAST OF THE TN RIVER THIS
EVENING.
PWB
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1058 AM CDT SAT AUG 15 2015
.UPDATE...
THE MAIN UPDATE TO THE FORECAST TODAY WAS TO INCREASE PRECIP
CHANCES ESPECIALLY ACROSS PORTIONS OF WEST TN WHERE HI-RES
GUIDANCE SUPPORTS AFTERNOON THUNDERSTORM DEVELOPMENT. CURRENT
SHOWERS/TSTORMS WERE LOCATED ALONG THE TN RIVER DRIFTING SLOWLY
WEST THROUGH THE LATE MORNING. OUTFLOW FROM CURRENT STORMS SHOULD
FORCE NEW DEVELOPMENT IN THE BUOYANT AIRMASS AHEAD OF THE COLD
POOL DURING THE EARLY TO MID AFTERNOON HOURS. THIS ACTIVITY SHOULD
DECREASE IN COVERAGE/INTENSITY THROUGH THE LATE EVENING. ALSO
LOWERED HIGHS WHERE CURRENT CLOUD COVER/PRECIP IS LIMITING
WARMING.
TVT
&&
.PREV DISCUSSION... /ISSUED 437 AM CDT SAT AUG 15 2015/
DISCUSSION...
CURRENTLY...
A QUIET MID-AUGUST MORNING THROUGHOUT THE MIDSOUTH WITH LIGHT
SURFACE WINDS FROM THE NORTH AND TEMPERATURES NEAR NORMAL VALUES.
AREA RADARS ARE SHOWING A LINE OF LIGHT RETURNS STRETCHING ACROSS
NORTH MISSISSIPPI JUST SOUTH OF OUR CWA INTO NORTHWEST ALABAMA.
ONE LONE SHOWER EMBEDDED WITHIN THIS LINE HAS HEAVY ENOUGH RETURNS
TO SUGGEST THAT PRECIP MAY BE REACHING THE GROUND AS IT APPROACHES
KGWX AND MONROE COUNTY. ANOTHER ISOLATED SHOWER OR TWO MAY
DEVELOP DURING THE MORNING HOURS OVER NORTHEAST MISSISSIPPI BUT
THE REST OF THE MIDSOUTH WILL REMAIN DRY.
SHORT TERM...
THE PLEASANT WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE
WEEKEND WITH NEAR OR SLIGHTLY BELOW NORMAL TEMPS AND THE MAJORITY
OF THE MIDSOUTH REMAINING DRY. AFTERNOON THUNDERSTORM COVERAGE
WILL BE GREATER TODAY MAINLY IN THE EASTERN PORTIONS OF OUR REGION
AS AN UPPER LEVEL TROUGH CONTINUES TO DIG INTO THE REGION FROM
THE NORTH EAST. THE HRRR KEEPS AFTERNOON CONVECTION WEST OF THE
MS RIVER. THESE DIURNALLY DRIVEN STORMS SHOULD BEGIN TO WANE AS WE
LOSE DAYTIME HEATING. AFTERNOON STORM COVERAGE SHOULD INCREASE
EVEN MORE ON SUNDAY AS THE UPPER LOW MOVES WESTWARD AND LOWER
LEVEL SOUTHERLY FLOW INCREASES PULLING MORE MOISTURE INTO THE
SOUTHEASTERN STATES FROM THE GULF OF MEXICO.
LONG TERM...
HIGH TEMPERATURES WILL BE NEAR 90 DEGREES EACH DAY EARLY NEXT WEEK
WITH LOWS NEAR 70 AND CHANCES OF STORMS EACH EVENING.THE BEST
CHANCES OF AREA WIDE PRECIP DURING THE UPCOMING WEEK WILL BE ON
WEDNESDAY AS MODELS AGREE ON A STRENGTHENING UPPER TROUGH AND
ASSOCIATED SURFACE COLD FRONT MOVING THROUGH THE REGION. SOUTHERLY
FLOW WILL INCREASE AS THIS SYSTEM NEARS INCREASING MOISTURE
THROUGHOUT THE AREA. HEAT INDICES WILL APPROACH 100 DEGREES ON
WEDNESDAY BEFORE THE FRONT MATRICULATES THROUGH THE AREA BRINGING
WITH IT COOLER AIR FOR THURSDAY. MODELS AGREE ON AN UPPER LEVEL
HIGH BUILDING OVER THE SOUTHEASTERN UNITED STATES BY NEXT WEEKEND.
JPM3
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL FOR MUCH OF THE FORECAST PERIOD.
SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE LATE THIS AFTERNOON
INTO EARLY EVENING. WINDS WILL BE MAINLY FROM THE EAST AT 5 TO 10
KNOTS FOR MUCH OF THE FORECAST PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS NASHVILLE TN
659 AM CDT SAT AUG 15 2015
.UPDATE...FOR 12Z AVIATION DISCUSSION.
&&
.AVIATION UPDATE...12Z AVIATION DISCUSSION.
SEVERAL ADMS POSSIBLE THRU 16/12Z IF SHWR/TSTMS DIRECTLY IMPACT TAF SITES.
VFR CONDITIONS GENERALLY EXPECTED THRU 16/12Z. TRICKY TO PINPOINT EXACT
CONDITIONS AT TAF SITES THRU 16/12Z...ESPECIALLY AROUND CSV...PER AMPLE
LOW LEVEL MOISTURE RICH UNSTABLE AIR MASS IN PLACE...BUT WITH NO ORGANIZED
SFC FEATURES OF NOTE AND DIURNAL INFLUENCES PLAYING PRIMARY ROLE...ALONG/OR
WITH WEAK DISTURBANCES PASSAGES AND WEAK UPPER LEVEL LOW CIRCULATION ALOFT
IN SCT SHWR/TSTM DEVELOPMENT...WHICH COULD OCCUR ANYTIME THRU 16/12Z. ACTUAL
SIMPLIFICATION IN TAF FORECASTS SEEMS APPROPRIATE APPROACHING 15/12Z WITH
VCTS REMARKS AT ALL TAF SITES BY 15/17Z-16/12Z AS THE ADVECTION OF LOW LEVEL
MOISTURE CONTINUES WWD...WITH GENERALLY WITH SCT/BKN CB...SCT/BKN AC AND
BKN CI CLOUD COVER CONDITIONS POSSIBLE. SOME MVFR FOG POSSIBLE CKV/CSV ALSO
GENERALLY AFTER 16/06Z PER USUAL LOW LEVEL MOISTURE POOLING POTENTIAL WITH
INCREASED MOISTURE EVENTS. SFC PATTERN WILL SUPPORT GENERALLY LIGHT SELY
WINDS THRU 16/12Z ALSO.
&&
.PREV DISCUSSION.../ISSUED 338 AM CDT SAT AUG 15 2015/
DISCUSSION...
SHORT TERM(TODAY-MON)...
UPPER TROUGH AXIS WILL BE LOCATED DIRECTLY ACROSS THE
MID STATE TODAY. DEWPOINTS HAVE NOW INCHED UPWARD AND ARE GENERALLY
IN THE MID TO UPPER 60S. THUS...MOISTURE LEVELS ARE ON THE INCREASE
AS WE ARE GETTING MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT. GFS
ELUDES TO AN INCREASE IN UPPER DIVERGENCE FIELDS TOWARD 12Z. WE ARE
CURRENTLY SEEING AN AREA OF LIGHT ISOL SHOWER ACTIVITY ACROSS
SOUTHEASTERN AREAS OF THE MID STATE. HRRR ATTEMPTS TO EXPAND THIS
AREA NORTHWARD WITH FAIRLY DESCENT COVERAGE. IT APPEARS...SO
FAR...THAT THIS IS OVERDONE HOWEVER. SO FOR THE FCST TODAY...WILL
INCLUDE A SLIGHT CHANCE OF MORNING SHOWERS AND TSTMS EVERYWHERE.
THEN...I WILL INCREASE THAT INTO THE CHANCE CATEGORY FOR THE
AFTERNOON FOR ALL BUT THE FAR NORTHWESTERN AREAS.
TONIGHT AND SUNDAY...UPPER TROUGH REMAINS ALONG WITH A SLIGHT
ELEVATION IN MOISTURE LEVELS. NOT SEEING ANY APPARENT OVERNIGHT
DIVERGENCE AND LOW LEVEL DYNAMICS REMAIN WEAK. WILL THEREFORE
INCLUDE GENERALLY JUST A SLIGHT CHANCE OF SHOWERS AND TSTMS...EXCEPT
FOR 30 PERCENT PLATEAU ON SUN AFT.
BY MONDAY...MRH LEVELS BACK OFF A BIT AS THE UPPER TROUGH ERODES AND
WESTERLIES ATTEMPT TO RETURN. WILL STILL CARRY A 20 TO 30 PERCENT
CHANCE OF SHOWERS AND TSTMS AS CONVECTIVE ENERGY REMAINS.
FOR THE NEAR TERM TEMPS...VALUES FOR THE MOST PART WILL BE NEAR
SEASONAL LEVELS. MAY GO ABOVE THE MAV NUMBERS BY A DEGREE OR SO
TODAY AND TONIGHT.
LONG TERM(TUE-FRI)...
CONSENSUS MODEL SOLUTIONS SHOWING MORE OF A SWLY UPPER LEVEL FLOW
PATTERN THRU MID WEEK...WITH A BROAD UPPER LEVEL TROUGHING PATTERN
MOVING IN FROM THE CNTRL MS RIVER VALLEY REGION INTO THE MID STATE
AREA DURING THE LATER HALF OF THE WORK WEEK. THIS WILL BASICALLY
KEEP THE MID STATE UNDER A SWLY FLOW PATTERN ALOFT THRU THE ENTIRE
REMAINDER OF THE WORK WEEK...SUPPORTING CONVECTIVE POTENTIAL DAY
OR NIGHT. AT THE SFC...A SLY/SWLY SFC MOISTURE FETCH PATTERN WILL
CONTINUE DURING THIS TIME PERIOD ALSO PER MID ATLANTIC SFC HIGH
PRESSURE INFLUENCES. HOWEVER...NO SFC FRONTAL PASSAGES OF NOTE
ANTICIPATED. THESE EMBEDDED SHORTWAVE IN FLOW ALOFT...INTERACTING
WITH DIURNAL BASED INSTABILITY...LOW LEVEL ATM MOISTURE POTENTIAL...
ALONG WITH LOCAL OROGRAPHIC LIFTING AFFECTS...SHOULD SUPPORT MAINLY
SCT SHWRS/TSTMS THRU NEXT WORK WEEK ALONG WITH PTCLDY SKIES. THIS
WEATHER PATTERN WILL SUPPORT HIGH AND LOW TEMPS AROUND SEASONAL
NORMAL VALUES ALSO THRU THE REMAINDER OF NEXT WORK WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 86 67 89 69 / 30 20 20 20
CLARKSVILLE 87 66 88 66 / 20 20 20 20
CROSSVILLE 81 63 83 66 / 40 20 30 20
COLUMBIA 86 65 90 66 / 30 20 20 20
LAWRENCEBURG 87 66 89 67 / 30 20 20 20
WAVERLY 87 66 88 66 / 20 20 20 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
650 AM CDT SAT AUG 15 2015
.DISCUSSION...
HAVE OPTED TO INCREASE POPS ACROSS THE AREA. LATEST MODEL DATA
SHOWS A WEAK CUTOFF LOW ALONG THE UPPER TROUGH AXIS AND THIS
FEATURE SHOULD HOLD THROUGH MUCH OF THE DAY. FURTHERMORE...THE
CURRENT AREA OF ENHANCED MOISTURE WILL MOVE LITTLE AS WELL. HRRR
SHOWS A DEFINITIVE INCREASE IN COVERAGE THROUGH THE DAY.
WILL ALSO OPT TO CUT TEMPS BY A COUPLE DEGREES...PARTICULARLY
ACROSS EASTERN AREAS.
&&
.PREV DISCUSSION... /ISSUED 338 AM CDT SAT AUG 15 2015/
DISCUSSION...
SHORT TERM(TODAY-MON)...
UPPER TROUGH AXIS WILL BE LOCATED DIRECTLY ACROSS THE
MID STATE TODAY. DEWPOINTS HAVE NOW INCHED UPWARD AND ARE GENERALLY
IN THE MID TO UPPER 60S. THUS...MOISTURE LEVELS ARE ON THE INCREASE
AS WE ARE GETTING MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT. GFS
ELUDES TO AN INCREASE IN UPPER DIVERGENCE FIELDS TOWARD 12Z. WE ARE
CURRENTLY SEEING AN AREA OF LIGHT ISOL SHOWER ACTIVITY ACROSS
SOUTHEASTERN AREAS OF THE MID STATE. HRRR ATTEMPTS TO EXPAND THIS
AREA NORTHWARD WITH FAIRLY DESCENT COVERAGE. IT APPEARS...SO
FAR...THAT THIS IS OVERDONE HOWEVER. SO FOR THE FCST TODAY...WILL
INCLUDE A SLIGHT CHANCE OF MORNING SHOWERS AND TSTMS EVERYWHERE.
THEN...I WILL INCREASE THAT INTO THE CHANCE CATEGORY FOR THE
AFTERNOON FOR ALL BUT THE FAR NORTHWESTERN AREAS.
TONIGHT AND SUNDAY...UPPER TROUGH REMAINS ALONG WITH A SLIGHT
ELEVATION IN MOISTURE LEVELS. NOT SEEING ANY APPARENT OVERNIGHT
DIVERGENCE AND LOW LEVEL DYNAMICS REMAIN WEAK. WILL THEREFORE
INCLUDE GENERALLY JUST A SLIGHT CHANCE OF SHOWERS AND TSTMS...EXCEPT
FOR 30 PERCENT PLATEAU ON SUN AFT.
BY MONDAY...MRH LEVELS BACK OFF A BIT AS THE UPPER TROUGH ERODES AND
WESTERLIES ATTEMPT TO RETURN. WILL STILL CARRY A 20 TO 30 PERCENT
CHANCE OF SHOWERS AND TSTMS AS CONVECTIVE ENERGY REMAINS.
FOR THE NEAR TERM TEMPS...VALUES FOR THE MOST PART WILL BE NEAR
SEASONAL LEVELS. MAY GO ABOVE THE MAV NUMBERS BY A DEGREE OR SO
TODAY AND TONIGHT.
LONG TERM(TUE-FRI)...
CONSENSUS MODEL SOLUTIONS SHOWING MORE OF A SWLY UPPER LEVEL FLOW
PATTERN THRU MID WEEK...WITH A BROAD UPPER LEVEL TROUGHING PATTERN
MOVING IN FROM THE CNTRL MS RIVER VALLEY REGION INTO THE MID STATE
AREA DURING THE LATER HALF OF THE WORK WEEK. THIS WILL BASICALLY
KEEP THE MID STATE UNDER A SWLY FLOW PATTERN ALOFT THRU THE ENTIRE
REMAINDER OF THE WORK WEEK...SUPPORTING CONVECTIVE POTENTIAL DAY
OR NIGHT. AT THE SFC...A SLY/SWLY SFC MOISTURE FETCH PATTERN WILL
CONTINUE DURING THIS TIME PERIOD ALSO PER MID ATLANTIC SFC HIGH
PRESSURE INFLUENCES. HOWEVER...NO SFC FRONTAL PASSAGES OF NOTE
ANTICIPATED. THESE EMBEDDED SHORTWAVE IN FLOW ALOFT...INTERACTING
WITH DIURNAL BASED INSTABILITY...LOW LEVEL ATM MOISTURE POTENTIAL...
ALONG WITH LOCAL OROGRAPHIC LIFTING AFFECTS...SHOULD SUPPORT MAINLY
SCT SHWRS/TSTMS THRU NEXT WORK WEEK ALONG WITH PTCLDY SKIES. THIS
WEATHER PATTERN WILL SUPPORT HIGH AND LOW TEMPS AROUND SEASONAL
NORMAL VALUES ALSO THRU THE REMAINDER OF NEXT WORK WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 86 67 89 69 / 30 20 20 20
CLARKSVILLE 87 66 88 66 / 20 20 20 20
CROSSVILLE 81 63 83 66 / 50 20 30 20
COLUMBIA 86 65 90 66 / 30 20 20 20
LAWRENCEBURG 87 66 89 67 / 30 20 20 20
WAVERLY 87 66 88 66 / 20 20 20 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
627 AM CDT SAT AUG 15 2015
.UPDATE...
UPDATED FOR THE 12Z AVIATION DISCUSSION
&&
.PREV DISCUSSION... /ISSUED 437 AM CDT SAT AUG 15 2015/
DISCUSSION...
CURRENTLY...
A QUIET MID-AUGUST MORNING THROUGHOUT THE MIDSOUTH WITH LIGHT
SURFACE WINDS FROM THE NORTH AND TEMPERATURES NEAR NORMAL VALUES.
AREA RADARS ARE SHOWING A LINE OF LIGHT RETURNS STRETCHING ACROSS
NORTH MISSISSIPPI JUST SOUTH OF OUR CWA INTO NORTHWEST ALABAMA.
ONE LONE SHOWER EMBEDDED WITHIN THIS LINE HAS HEAVY ENOUGH RETURNS
TO SUGGEST THAT PRECIP MAY BE REACHING THE GROUND AS IT APPROACHES
KGWX AND MONROE COUNTY. ANOTHER ISOLATED SHOWER OR TWO MAY
DEVELOP DURING THE MORNING HOURS OVER NORTHEAST MISSISSIPPI BUT
THE REST OF THE MIDSOUTH WILL REMAIN DRY.
SHORT TERM...
THE PLEASANT WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE
WEEKEND WITH NEAR OR SLIGHTLY BELOW NORMAL TEMPS AND THE MAJORITY
OF THE MIDSOUTH REMAINING DRY. AFTERNOON THUNDERSTORM COVERAGE
WILL BE GREATER TODAY MAINLY IN THE EASTERN PORTIONS OF OUR REGION
AS AN UPPER LEVEL TROUGH CONTINUES TO DIG INTO THE REGION FROM
THE NORTH EAST. THE HRRR KEEPS AFTERNOON CONVECTION WEST OF THE
MS RIVER. THESE DIURNALLY DRIVEN STORMS SHOULD BEGIN TO WANE AS WE
LOSE DAYTIME HEATING. AFTERNOON STORM COVERAGE SHOULD INCREASE
EVEN MORE ON SUNDAY AS THE UPPER LOW MOVES WESTWARD AND LOWER
LEVEL SOUTHERLY FLOW INCREASES PULLING MORE MOISTURE INTO THE
SOUTHEASTERN STATES FROM THE GULF OF MEXICO.
LONG TERM...
HIGH TEMPERATURES WILL BE NEAR 90 DEGREES EACH DAY EARLY NEXT WEEK
WITH LOWS NEAR 70 AND CHANCES OF STORMS EACH EVENING.THE BEST
CHANCES OF AREA WIDE PRECIP DURING THE UPCOMING WEEK WILL BE ON
WEDNESDAY AS MODELS AGREE ON A STRENGTHENING UPPER TROUGH AND
ASSOCIATED SURFACE COLD FRONT MOVING THROUGH THE REGION. SOUTHERLY
FLOW WILL INCREASE AS THIS SYSTEM NEARS INCREASING MOISTURE
THROUGHOUT THE AREA. HEAT INDICES WILL APPROACH 100 DEGREES ON
WEDNESDAY BEFORE THE FRONT MATRICULATES THROUGH THE AREA BRINGING
WITH IT COOLER AIR FOR THURSDAY. MODELS AGREE ON AN UPPER LEVEL
HIGH BUILDING OVER THE SOUTHEASTERN UNITED STATES BY NEXT WEEKEND.
JPM3
&&
.AVIATION...
12Z TAF CYCLE
VFR CONDITIONS SHOULD PREVAIL FOR MUCH OF THE FORECAST PERIOD.
SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE LATE THIS AFTERNOON
INTO EARLY EVENING. WINDS WILL BE MAINLY FROM THE EAST AT 5 TO 10
KNOTS FOR MUCH OF THE FORECAST PERIOD.
ARS
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
437 AM CDT SAT AUG 15 2015
.DISCUSSION...
CURRENTLY...
A QUIET MID-AUGUST MORNING THROUGHOUT THE MIDSOUTH WITH LIGHT
SURFACE WINDS FROM THE NORTH AND TEMPERATURES NEAR NORMAL VALUES.
AREA RADARS ARE SHOWING A LINE OF LIGHT RETURNS STRETCHING ACROSS
NORTH MISSISSIPPI JUST SOUTH OF OUR CWA INTO NORTHWEST ALABAMA.
ONE LONE SHOWER EMBEDDED WITHIN THIS LINE HAS HEAVY ENOUGH RETURNS
TO SUGGEST THAT PRECIP MAY BE REACHING THE GROUND AS IT APPROACHES
KGWX AND MONROE COUNTY. ANOTHER ISOLATED SHOWER OR TWO MAY
DEVELOP DURING THE MORNING HOURS OVER NORTHEAST MISSISSIPPI BUT
THE REST OF THE MIDSOUTH WILL REMAIN DRY.
SHORT TERM...
THE PLEASANT WEATHER WILL CONTINUE THROUGH THE REMAINDER OF THE
WEEKEND WITH NEAR OR SLIGHTLY BELOW NORMAL TEMPS AND THE MAJORITY
OF THE MIDSOUTH REMAINING DRY. AFTERNOON THUNDERSTORM COVERAGE
WILL BE GREATER TODAY MAINLY IN THE EASTERN PORTIONS OF OUR REGION
AS AN UPPER LEVEL TROUGH CONTINUES TO DIG INTO THE REGION FROM
THE NORTH EAST. THE HRRR KEEPS AFTERNOON CONVECTION WEST OF THE
MS RIVER. THESE DIURNALLY DRIVEN STORMS SHOULD BEGIN TO WANE AS WE
LOSE DAYTIME HEATING. AFTERNOON STORM COVERAGE SHOULD INCREASE
EVEN MORE ON SUNDAY AS THE UPPER LOW MOVES WESTWARD AND LOWER
LEVEL SOUTHERLY FLOW INCREASES PULLING MORE MOISTURE INTO THE
SOUTHEASTERN STATES FROM THE GULF OF MEXICO.
LONG TERM...
HIGH TEMPERATURES WILL BE NEAR 90 DEGREES EACH DAY EARLY NEXT WEEK
WITH LOWS NEAR 70 AND CHANCES OF STORMS EACH EVENING.THE BEST
CHANCES OF AREA WIDE PRECIP DURING THE UPCOMING WEEK WILL BE ON
WEDNESDAY AS MODELS AGREE ON A STRENGTHENING UPPER TROUGH AND
ASSOCIATED SURFACE COLD FRONT MOVING THROUGH THE REGION. SOUTHERLY
FLOW WILL INCREASE AS THIS SYSTEM NEARS INCREASING MOISTURE
THROUGHOUT THE AREA. HEAT INDICES WILL APPROACH 100 DEGREES ON
WEDNESDAY BEFORE THE FRONT MATRICULATES THROUGH THE AREA BRINGING
WITH IT COOLER AIR FOR THURSDAY. MODELS AGREE ON AN UPPER LEVEL
HIGH BUILDING OVER THE SOUTHEASTERN UNITED STATES BY NEXT WEEKEND.
JPM3
&&
.AVIATION...
06Z TAF CYCLE
VFR CIGS SHOULD PREVAIL THROUGH THE PERIOD. REDUCED VSBYS...POTENTIALLY
TO IFR...WILL BE POSSIBLE AT KMKL DUE TO EARLY MORNING FOG
SATURDAY. WINDS WILL REMAIN LIGHT EASTERLY/NORTHEASTERLY TONIGHT.
HUMIDITY LEVELS WILL INCREASE ON SATURDAY AS AN INVERTED SURFACE
TROUGH APPROACHES FROM THE EAST. THIS SHOULD LEAD TO VICINITY
THUNDERSTORM CHANCES AT KTUP...KMKL...AND KMEM BY SATURDAY
AFTERNOON. WINDS SHOULD REMAIN EASTERLY/SOUTHEASTERLY AT 7 KTS OR
LESS ON SATURDAY. CONVECTION SHOULD DIMINISH SATURDAY EVENING WITH
LIGHT WINDS.
JLH
&&
.MEG WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
MO...NONE.
MS...NONE.
TN...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
338 AM CDT SAT AUG 15 2015
.DISCUSSION...
.SHORT TERM(TODAY-MON)...
UPPER TROUGH AXIS WILL BE LOCATED DIRECTLY ACROSS THE
MID STATE TODAY. DEWPOINTS HAVE NOW INCHED UPWARD AND ARE GENERALLY
IN THE MID TO UPPER 60S. THUS...MOISTURE LEVELS ARE ON THE INCREASE
AS WE ARE GETTING MORE OF A SOUTHERLY LOW LEVEL WIND COMPONENT. GFS
ELUDES TO AN INCREASE IN UPPER DIVERGENCE FIELDS TOWARD 12Z. WE ARE
CURRENTLY SEEING AN AREA OF LIGHT ISOL SHOWER ACTIVITY ACROSS
SOUTHEASTERN AREAS OF THE MID STATE. HRRR ATTEMPTS TO EXPAND THIS
AREA NORTHWARD WITH FAIRLY DESCENT COVERAGE. IT APPEARS...SO
FAR...THAT THIS IS OVERDONE HOWEVER. SO FOR THE FCST TODAY...WILL
INCLUDE A SLIGHT CHANCE OF MORNING SHOWERS AND TSTMS EVERYWHERE.
THEN...I WILL INCREASE THAT INTO THE CHANCE CATEGORY FOR THE
AFTERNOON FOR ALL BUT THE FAR NORTHWESTERN AREAS.
TONIGHT AND SUNDAY...UPPER TROUGH REMAINS ALONG WITH A SLIGHT
ELEVATION IN MOISTURE LEVELS. NOT SEEING ANY APPARENT OVERNIGHT
DIVERGENCE AND LOW LEVEL DYNAMICS REMAIN WEAK. WILL THEREFORE
INCLUDE GENERALLY JUST A SLIGHT CHANCE OF SHOWERS AND TSTMS...EXCEPT
FOR 30 PERCENT PLATEAU ON SUN AFT.
BY MONDAY...MRH LEVELS BACK OFF A BIT AS THE UPPER TROUGH ERODES AND
WESTERLIES ATTEMPT TO RETURN. WILL STILL CARRY A 20 TO 30 PERCENT
CHANCE OF SHOWERS AND TSTMS AS CONVECTIVE ENERGY REMAINS.
FOR THE NEAR TERM TEMPS...VALUES FOR THE MOST PART WILL BE NEAR
SEASONAL LEVELS. MAY GO ABOVE THE MAV NUMBERS BY A DEGREE OR SO
TODAY AND TONIGHT.
.LONG TERM(TUE-FRI)...
CONSENSUS MODEL SOLUTIONS SHOWING MORE OF A SWLY UPPER LEVEL FLOW
PATTERN THRU MID WEEK...WITH A BROAD UPPER LEVEL TROUGHING PATTERN
MOVING IN FROM THE CNTRL MS RIVER VALLEY REGION INTO THE MID STATE
AREA DURING THE LATER HALF OF THE WORK WEEK. THIS WILL BASICALLY
KEEP THE MID STATE UNDER A SWLY FLOW PATTERN ALOFT THRU THE ENTIRE
REMAINDER OF THE WORK WEEK...SUPPORTING CONVECTIVE POTENTIAL DAY
OR NIGHT. AT THE SFC...A SLY/SWLY SFC MOISTURE FETCH PATTERN WILL
CONTINUE DURING THIS TIME PERIOD ALSO PER MID ATLANTIC SFC HIGH
PRESSURE INFLUENCES. HOWEVER...NO SFC FRONTAL PASSAGES OF NOTE
ANTICIPATED. THESE EMBEDDED SHORTWAVE IN FLOW ALOFT...INTERACTING
WITH DIURNAL BASED INSTABILITY...LOW LEVEL ATM MOISTURE POTENTIAL...
ALONG WITH LOCAL OROGRAPHIC LIFTING AFFECTS...SHOULD SUPPORT MAINLY
SCT SHWRS/TSTMS THRU NEXT WORK WEEK ALONG WITH PTCLDY SKIES. THIS
WEATHER PATTERN WILL SUPPORT HIGH AND LOW TEMPS AROUND SEASONAL
NORMAL VALUES ALSO THRU THE REMAINDER OF NEXT WORK WEEK.
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 86 67 89 69 / 30 20 20 20
CLARKSVILLE 87 66 88 66 / 20 20 20 20
CROSSVILLE 81 63 83 66 / 30 20 30 20
COLUMBIA 86 65 90 66 / 30 20 20 20
LAWRENCEBURG 87 66 89 67 / 30 20 20 20
WAVERLY 87 66 88 66 / 20 20 20 20
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
21/31
AREA FORECAST DISCUSSION...UPDATED
NWS AUSTIN/SAN ANTONIO TX
1251 PM CDT SAT AUG 15 2015
.AVIATION.../18Z TAF CYCLE/
VFR CONDITIONS PREVAIL ACROSS ALL TAF SITES THIS AFTERNOON WITH
ISOLATED SHRA/TSRA LOCATED BETWEEN KDRT AND KSAT. THIS SHRA/TSRA
ACTIVITY IS MOVING TO THE SW AND WILL NOT IMPACT KDRT.
HOWEVER...ADDITIONAL SHRA/TSRA IS BEGINNING TO DEVELOP BACK UPSTREAM
ACROSS THE HILL COUNTRY AND NORTH OF KAUS. THIS ACTIVITY WILL
EXPAND IN COVERAGE THROUGH THE AFTERNOON AND DRIFT SW TOWARDS THE
MAJOR TERMINALS. HAVE PLACED VCSH IN CENTRAL TAF SITES FROM 1830Z
THROUGH 01Z TONIGHT. SOME STORMS MAY HAVE LOCAL 30-50 MPH WIND GUSTS
AND HEAVY DOWNPOURS. MVFR CONDITIONS COULD BE POSSIBLE IF A STORM
DIRECTLY IMPACTS A TERMINAL SITE. WILL MONITOR TRENDS THROUGH THE
AFTERNOON IF DIRECT SHRA/TSRA IS NEEDED. THIS ACTIVITY WILL
DISSIPATE OVERNIGHT WITH VFR CONTINUING.
&&
.PREV DISCUSSION... /ISSUED 827 AM CDT SAT AUG 15 2015/
UPDATE...
HAVE EXTENDED CHANCE POPS TO THE NORTH INTO THE HILL COUNTRY AND
FARTHER SOUTH THIS MORNING...WHILE ADDING CHANCE POPS WESTWARD
TOWARDS THE RIO GRANDE PLAINS FOR THE AFTERNOON HOURS. RE-TRENDED
ALL OF THE HOURLY GRIDS TO REFLECT MORNING OBSERVATIONS.
DISCUSSION...
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED FROM TRAVIS COUNTY
SOUTHWARD THROUGH COMAL AND BEXAR COUNTY. FREQUENT LIGHTNING IS
THE PRIMARY CONCERN WITH THESE STORMS BUT A BRIEF WIND GUST IS
ALSO POSSIBLE. CENTRAL TEXAS CURRENTLY SITS ON THE EASTERN
PERIPHERY OF THE HIGH PRESSURE THAT HAS BEEN PLAGUING US WITH THE
HOT AND DRY TEMPERATURES FOR THE LAST FEW WEEKS. A TROUGH IS
TAKING SHAPE ON THE EASTERN SIDE OF THE HIGH. BASED ON MORNING RAP
MODEL ANALYSIS THERE ARE SUBTLE SIGNS THAT A SHORT WAVE AT THE
TAIL END OF THIS TROUGH SITUATED OVER EAST TEXAS IS WHAT IS
KICKING OFF THESE SHOWERS AND THUNDERSTORMS. THE HRRR AND TEXAS
TECH WRF ALSO PICK UP IN THIS FEATURE IN THEIR MODEL REFLECTIVITY
FIELDS AS THEY CONTINUE TO KICK OFF SHOWERS AND STORMS JUST WEST
OF I-35 THROUGH THE MORNING HOURS BEFORE SHIFTING THE FOCUS
TOWARDS THE EDWARDS PLATEAU FOR THE AFTERNOON AND EVENING HOURS. A
PRE-PACKAGE UPDATE MAY BE NEEDED TO BUMP UP POPS EVEN MORE ACROSS
THE EDWARDS PLATEAU BASED ON RADAR TRENDS AND THE 12Z MODELS.
PREV DISCUSSION... /ISSUED 627 AM CDT SAT AUG 15 2015/
AVIATION...
/12Z TAFS/
AN ISOLATED SHOWER OR TWO MAY CREATE MVFR CIGS ACROSS KAUS FOR FEW
HOURS EARLY THIS MORNING. OTHERWISE...VFR CONDITIONS ARE EXPECTED
ACROSS AREA TERMINALS THROUGH THE FORECAST PERIOD. LIGHT SOUTHERLY
WINDS TO PREVAIL FOR MUCH OF THE AREA TODAY WITH HIGHER GUSTS
ACROSS THE RIO GRANDE PLAINS AND NEAR NEWLY STORMS THAT DEVELOP
THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 356 AM CDT SAT AUG 15 2015/
SHORT TERM (TODAY THROUGH SUNDAY)...
15/00Z UPPER AIR DATA SHOWS HIGH PRESSURE CENTERED OVER THE DESERT
SOUTHWEST...WITH NORTHERLY FLOW IN THE MID AND UPPER LEVELS ACROSS
SOUTH CENTRAL TEXAS. SOME WEAK MID-LEVEL SHORTWAVES EMBEDDED IN
THE NORTHERLY FLOW ALOFT WILL MOVE THROUGH THE REGION TODAY. THIS
ALONG WITH DAYTIME HEATING SHOULD GENERATE ISOLATED TO SCATTERED
CONVECTION...WITH THE BEST CHANCE REMAINING ACROSS THE SOUTHERN
EDWARDS PLATEAU AND WESTERN HILL COUNTRY. WE/LL ALSO INCLUDE A
CHANCE ACROSS THE COASTAL PLAINS AS THE HI-RES MODELS DO SHOW SOME
ACTIVITY DEVELOPING THIS AFTERNOON. ON SUNDAY...THE MODELS SUGGEST
A MID-LEVEL TROUGH WILL BEGIN TO DEVELOP ALONG THE TEXAS COAST
INTO PORTIONS OF EAST TEXAS. THIS SHOULD SHIFT THE FOCUS FOR
CONVECTION ALONG AND EAST OF I-35...ESPECIALLY NEAR THE COASTAL
PLAINS. AS FOR TEMPERATURES...HIGHS WILL REMAIN SLIGHTLY ABOVE
NORMAL TODAY...WITH NEAR NORMAL READINGS EXPECTED TOMORROW. LOW
TEMPERATURES SHOULD REMAIN NEAR SEASONAL LEVELS.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
THE ABOVE MENTIONED MID-LEVEL TROUGH CONTINUES TO BE THE DOMINANT
WEATHER FEATURE THROUGH THE WEEKEND INTO EARLY NEXT WEEK ACROSS
SOUTH CENTRAL TEXAS. THE MODELS DO SHOW SOME DISAGREEMENT IN HOW
FAR WEST THIS TROUGH WILL RETROGRADE...WITH THE CANADIAN BEING ONE
OF THE FARTHEST WEST. FOR NOW...WE/LL KEEP RAIN CHANCES CONFINED
TO AREAS GENERALLY ALONG AND EAST OF I-35 THROUGH TUESDAY GIVEN
DEEPER MOISTURE NEAR THE TEXAS COAST. BY MID-WEEK...A FAIRLY
STRONG UPPER TROUGH WILL MOVE ACROSS THE CENTRAL AND HIGH PLAINS
STATES. THIS WILL SEND A COLD FRONT SOUTHWARD INTO THE SOUTHERN
PLAINS LATE WEDNESDAY OR THURSDAY. THE MEDIUM RANGE MODELS DIFFER
WITH REGARDS TO THE STRENGTH OF THIS FRONT AND FOR NOW...WE/LL
GENERALLY FOLLOW THE FARTHER SOUTH GFS SOLUTION. THIS WILL RESULT
IN A CHANCE FOR MORE WIDESPREAD PRECIPITATION MID TO LATE WEEK
ALONG WITH A SLIGHT COOLING TREND.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 98 75 95 75 / 10 10 20 20 10
AUSTIN BERGSTROM INTL AIRPORT 72 97 72 95 73 / 10 10 20 20 10
NEW BRAUNFELS MUNI AIRPORT 74 97 73 95 74 / 10 20 20 20 10
BURNET MUNI AIRPORT 73 96 73 94 73 / 10 10 10 10 0
DEL RIO INTL AIRPORT 77 100 76 98 77 / 10 - - 0 0
GEORGETOWN MUNI AIRPORT 75 97 74 95 75 / 10 10 20 20 10
HONDO MUNI AIRPORT 73 97 72 95 73 / 10 10 10 10 -
SAN MARCOS MUNI AIRPORT 74 97 74 94 74 / 10 10 20 20 10
LA GRANGE - FAYETTE REGIONAL 75 96 74 95 75 / 10 20 20 30 20
SAN ANTONIO INTL AIRPORT 76 97 75 95 76 / 10 20 20 20 10
STINSON MUNI AIRPORT 75 98 74 95 75 / 10 20 20 20 10
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...TREADWAY
PUBLIC SERVICE/DATA COLLECTION...LH
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
827 AM CDT SAT AUG 15 2015
.UPDATE...
HAVE EXTENDED CHANCE POPS TO THE NORTH INTO THE HILL COUNTRY AND
FARTHER SOUTH THIS MORNING...WHILE ADDING CHANCE POPS WESTWARD
TOWARDS THE RIO GRANDE PLAINS FOR THE AFTERNOON HOURS. RE-TRENDED
ALL OF THE HOURLY GRIDS TO REFLECT MORNING OBSERVATIONS.
&&
.DISCUSSION...
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED FROM TRAVIS COUNTY
SOUTHWARD THROUGH COMAL AND BEXAR COUNTY. FREQUENT LIGHTNING IS
THE PRIMARY CONCERN WITH THESE STORMS BUT A BRIEF WIND GUST IS
ALSO POSSIBLE. CENTRAL TEXAS CURRENTLY SITS ON THE EASTERN
PERIPHERY OF THE HIGH PRESSURE THAT HAS BEEN PLAGUING US WITH THE
HOT AND DRY TEMPERATURES FOR THE LAST FEW WEEKS. A TROUGH IS
TAKING SHAPE ON THE EASTERN SIDE OF THE HIGH. BASED ON MORNING RAP
MODEL ANALYSIS THERE ARE SUBTLE SIGNS THAT A SHORT WAVE AT THE
TAIL END OF THIS TROUGH SITUATED OVER EAST TEXAS IS WHAT IS
KICKING OFF THESE SHOWERS AND THUNDERSTORMS. THE HRRR AND TEXAS
TECH WRF ALSO PICK UP IN THIS FEATURE IN THEIR MODEL REFLECTIVITY
FIELDS AS THEY CONTINUE TO KICK OFF SHOWERS AND STORMS JUST WEST
OF I-35 THROUGH THE MORNING HOURS BEFORE SHIFTING THE FOCUS
TOWARDS THE EDWARDS PLATEAU FOR THE AFTERNOON AND EVENING HOURS. A
PRE-PACKAGE UPDATE MAY BE NEEDED TO BUMP UP POPS EVEN MORE ACROSS
THE EDWARDS PLATEAU BASED ON RADAR TRENDS AND THE 12Z MODELS.
&&
.PREV DISCUSSION... /ISSUED 627 AM CDT SAT AUG 15 2015/
AVIATION...
/12Z TAFS/
AN ISOLATED SHOWER OR TWO MAY CREATE MVFR CIGS ACROSS KAUS FOR FEW
HOURS EARLY THIS MORNING. OTHERWISE...VFR CONDITIONS ARE EXPECTED
ACROSS AREA TERMINALS THROUGH THE FORECAST PERIOD. LIGHT SOUTHERLY
WINDS TO PREVAIL FOR MUCH OF THE AREA TODAY WITH HIGHER GUSTS
ACROSS THE RIO GRANDE PLAINS AND NEAR NEWLY STORMS THAT DEVELOP
THIS AFTERNOON.
PREV DISCUSSION... /ISSUED 356 AM CDT SAT AUG 15 2015/
SHORT TERM (TODAY THROUGH SUNDAY)...
15/00Z UPPER AIR DATA SHOWS HIGH PRESSURE CENTERED OVER THE DESERT
SOUTHWEST...WITH NORTHERLY FLOW IN THE MID AND UPPER LEVELS ACROSS
SOUTH CENTRAL TEXAS. SOME WEAK MID-LEVEL SHORTWAVES EMBEDDED IN
THE NORTHERLY FLOW ALOFT WILL MOVE THROUGH THE REGION TODAY. THIS
ALONG WITH DAYTIME HEATING SHOULD GENERATE ISOLATED TO SCATTERED
CONVECTION...WITH THE BEST CHANCE REMAINING ACROSS THE SOUTHERN
EDWARDS PLATEAU AND WESTERN HILL COUNTRY. WE/LL ALSO INCLUDE A
CHANCE ACROSS THE COASTAL PLAINS AS THE HI-RES MODELS DO SHOW SOME
ACTIVITY DEVELOPING THIS AFTERNOON. ON SUNDAY...THE MODELS SUGGEST
A MID-LEVEL TROUGH WILL BEGIN TO DEVELOP ALONG THE TEXAS COAST
INTO PORTIONS OF EAST TEXAS. THIS SHOULD SHIFT THE FOCUS FOR
CONVECTION ALONG AND EAST OF I-35...ESPECIALLY NEAR THE COASTAL
PLAINS. AS FOR TEMPERATURES...HIGHS WILL REMAIN SLIGHTLY ABOVE
NORMAL TODAY...WITH NEAR NORMAL READINGS EXPECTED TOMORROW. LOW
TEMPERATURES SHOULD REMAIN NEAR SEASONAL LEVELS.
LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)...
THE ABOVE MENTIONED MID-LEVEL TROUGH CONTINUES TO BE THE DOMINANT
WEATHER FEATURE THROUGH THE WEEKEND INTO EARLY NEXT WEEK ACROSS
SOUTH CENTRAL TEXAS. THE MODELS DO SHOW SOME DISAGREEMENT IN HOW
FAR WEST THIS TROUGH WILL RETROGRADE...WITH THE CANADIAN BEING ONE
OF THE FARTHEST WEST. FOR NOW...WE/LL KEEP RAIN CHANCES CONFINED
TO AREAS GENERALLY ALONG AND EAST OF I-35 THROUGH TUESDAY GIVEN
DEEPER MOISTURE NEAR THE TEXAS COAST. BY MID-WEEK...A FAIRLY
STRONG UPPER TROUGH WILL MOVE ACROSS THE CENTRAL AND HIGH PLAINS
STATES. THIS WILL SEND A COLD FRONT SOUTHWARD INTO THE SOUTHERN
PLAINS LATE WEDNESDAY OR THURSDAY. THE MEDIUM RANGE MODELS DIFFER
WITH REGARDS TO THE STRENGTH OF THIS FRONT AND FOR NOW...WE/LL
GENERALLY FOLLOW THE FARTHER SOUTH GFS SOLUTION. THIS WILL RESULT
IN A CHANCE FOR MORE WIDESPREAD PRECIPITATION MID TO LATE WEEK
ALONG WITH A SLIGHT COOLING TREND.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 98 76 98 75 95 / 20 10 10 20 20
AUSTIN BERGSTROM INTL AIRPORT 98 72 97 72 95 / 20 10 10 20 20
NEW BRAUNFELS MUNI AIRPORT 97 74 97 73 95 / 30 10 20 20 20
BURNET MUNI AIRPORT 96 73 96 73 94 / 30 10 10 10 10
DEL RIO INTL AIRPORT 99 77 100 76 98 / 20 10 - - 0
GEORGETOWN MUNI AIRPORT 97 75 97 74 95 / 20 10 10 20 20
HONDO MUNI AIRPORT 97 73 97 72 95 / 30 10 10 10 10
SAN MARCOS MUNI AIRPORT 97 74 97 74 94 / 20 10 10 20 20
LA GRANGE - FAYETTE REGIONAL 99 75 96 74 95 / 20 10 20 20 30
SAN ANTONIO INTL AIRPORT 98 76 97 75 95 / 30 10 20 20 20
STINSON MUNI AIRPORT 98 75 98 74 95 / 30 10 20 20 20
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...ALLEN
SYNOPTIC/GRIDS...TREADWAY
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
121 AM EDT MON AUG 17 2015
.PREV DISCUSSION... /ISSUED 726 PM EDT SUN AUG 16 2015/
UPDATE...
MADE A FEW CHANGES TO THE FORECAST...MAINLY TO POPS FOR OVERNIGHT
INTO TOMORROW. THE NAM SHOWS A WEAK WAVE MOVING THROUGH
TONIGHT...AND THE HRRR DOES DEVELOP SOME SHOWERS WITH THIS
FEATURE. CURRENTLY...THE BEST TIMING FOR THESE SHOWERS LOOKS TO BE
RIGHT BEFORE DAWN. NOT TOO CONFIDENT ON THE COVERAGE...SO KEPT
POPS CAPPED AROUND 30-40 PERCENT. ALSO TWEAKED THE TIMING FOR THE
AFTERNOON SHRA/TSRA FOR TOMORROW AFTERNOON.
PREV DISCUSSION... /ISSUED 335 PM EDT SUN AUG 16 2015/
SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
AIRMASS IS MODIFYING WITH A MORNING SOUNDING SHOWING 1.5 PWS AND
OVER 3500 MUCAPE... ALL WITH NO CAP. THE GREATER AFTERNOON STORM
CHANCES WILL BE ACROSS FAR NORTH GA WHERE AN UPPER TROUGH IS NEARER
TO NW GA AND OROGRAPHIC LIFT WILL ENHANCE CONVECTION IN THE
MOUNTAINS... AND ACROSS CENTRAL GA WHERE DEEP ATLANTIC MOISTURE IS
ON THE INCREASE. REGIONAL RADARS ARE SHOWING SCATTERED TO NUMEROUS
SHOWERS WITH SOME EMBEDDED THUNDERSTORMS ALREADY DEVELOPING ACROSS
CENTRAL GA... MAINLY ALONG AND SOUTH OF A FRANKLIN TO LOUISVILLE
LINE AND DRIFTING NORTHWARD. AIRMASS WOULD SUPPORT DEVELOPMENT JUST
ABOUT ANYWHERE... SO HAVE INCREASED POPS THROUGH THE EVENING FOR
MOST AREAS... WITH LIKELY POPS ACROSS MUCH OF CENTRAL GA. ALTHOUGH
STORMS ARE EXPECTED TO REMAIN BELOW SEVERE LIMITS WITH LITTLE SHEAR
OR FORCING NOTED... CANNOT RULE OUT A FEW STRONG STORMS BETWEEN 4-9
PM TODAY. THE THUNDERSTORM THREAT SHOULD END BY 9 PM THIS EVENING...
BUT ISOLATED TO POSSIBLY SCATTERED SHOWERS COULD LINGER OVERNIGHT.
THIS IS LARGELY DUE TO AN UPPER TROUGH ALONG THE MS VALLEY REGION
THAT WILL BEGIN TO DRIFT EASTWARD TONIGHT... AND PROVIDE AN SUPPORT
FOR INCREASING RAIN CHANCES FROM THE WEST BEGINNING MONDAY
MORNING... THEN BECOMING SCATTERED TO NUMEROUS IN COVERAGE FOR MOST
AREAS BY MID MONDAY AFTERNOON. NOT EXPECTING SEVERE STORMS ON
MONDAY... BUT A FEW STORMS COULD BE STRONG MONDAY AFTERNOON WITH
WIND GUSTS TO 45 MPH AND FREQUENT LIGHTNING BEING THE MAIN THREATS.
HIGH PWS WOULD ALSO SUPPORT LOCALLY HEAVY RAIN AND BRIEF PONDING OF
WATER IS LIKELY ACROSS LOW LYING AREAS. SCATTERED CONVECTION IS
EXPECTED TO CONTINUE ACROSS THE AREA MONDAY NIGHT... BUT MOSTLY IN
THE FORM OF SHOWERS.
ALTHOUGH A FEW SHOWERS WILL BE POSSIBLY TONIGHT... EXPECTING LOW
CLOUDS AND PATCHY FOG TO DEVELOP ACROSS CENTRAL GA AND SPREAD
NORTHWARD TOWARD MONDAY MORNING. THIS WILL HELP HOLD TEMPS AND
INSTABILITIES DOWN ON MONDAY... ALL SUPPORTING A LESSOR CHANCE FOR
SEVERE STORMS.
OTHERWISE... A MAV AND MET BLEND GAVE NEAR NORMAL TEMPS THROUGH THE
FORECAST PERIOD... WHICH LOOKS REASONABLE... SO DID NOT STRAY.
39
LONG TERM /TUESDAY THROUGH SUNDAY/...
NO CHANGES MADE TO THE EXTENDED FORECAST. DEEP MOISTURE ASSOCIATED
WITH SW FLOW ALOFT WILL BE ACROSS THE AREA TO START THE LONG TERM
WITH RATHER HIGH PRECIPITATION CHANCES TUESDAY. EVEN THOUGH AN
UPPER RIDGE BUILDS SLIGHTLY OVER S GA ON WEDNESDAY...A MOIST
AIRMASS WILL CONTINUE FROM SW FLOW ALOFT. THE UPPER RIDGE
CONTINUES TO BUILD ON THURSDAY WITH THE SW FLOW ALOFT BECOMING
WEAKER BUT A MOIST AIRMASS CONTINUES OVER THE AREA...MOST SO ON
THE GFS AND LESS SO ON THE EUROPEAN. THE UPPER RIDGE CONTINUES TO
BUILD FRIDAY AND SATURDAY WITH A RATHER MOIST AIRMASS CONTINUING
ALLOWING FOR AT LEAST A CHANCE OF SHOWERS AND THUNDERSTORMS EACH
DAY.
FORECAST LOW TEMPERATURES EXPECTED TO BE AROUND NORMAL AND FORECAST HIGH
TEMPERATURES START OUT BELOW NORMAL BUT ARE EXPECTED TO WARM AROUND
NORMAL TOWARD WEEKS END.
BDL/01
&&
.AVIATION...
06Z UPDATE...
MOSTLY VFR CIGS AT THIS TIME BUT EXPECT MVFR/IFR CIGS TO DEVELOP
THROUGH THE EARLY MORNING HOURS...RISING TO VFR BY NOON.
SHOWERS/TSTORMS WILL BEGIN DEVELOPING BY MID MORNING AND BECOME
SCATTERED TO WIDESPREAD THIS AFTERNOON...DIMINISHING THIS EVENING.
WINDS WILL BE SOUTHEAST THROUGH THIS EVENING...BECOMING SOUTHWEST
AFTER 06Z TUESDAY IN ATL.
//ATL CONFIDENCE...06Z UPDATE...
MEDIUM ON CIGS AND TIMING OF SHRA/TSRA
HIGH ON REMAINING ELEMENTS
17
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 87 71 86 71 / 70 70 70 70
ATLANTA 85 73 85 72 / 70 70 70 70
BLAIRSVILLE 80 66 79 65 / 80 80 70 60
CARTERSVILLE 85 70 85 70 / 80 80 70 60
COLUMBUS 88 74 89 73 / 60 60 60 50
GAINESVILLE 83 71 82 71 / 70 70 70 70
MACON 88 73 89 72 / 60 60 60 70
ROME 84 71 85 70 / 80 80 70 60
PEACHTREE CITY 85 71 86 70 / 70 70 60 60
VIDALIA 89 73 89 72 / 60 60 70 30
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...17
LONG TERM....BDL
AVIATION...17
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1231 AM CDT MON AUG 17 2015
.UPDATE...
ISSUED AT 928 PM CDT SUN AUG 16 2015
CONCERN THIS EVENING REMAINS FLASH FLOOD POTENTIAL. RADAR
ESTIMATES AND OBSERVATIONS INDICATE PORTIONS OF ABOUT FOUR NW/N
CENTRAL COUNTIES HAVE SEEN TWO TO THREE INCHES OF RAINFALL
ALREADY. PWATS AND WARM CLOUD DEPTHS ARE ALL QUITE FAVORABLE FOR
VERY EFFICIENT RAINS BUT WEAKENING INSTABILITY WITH LOSS OF
HEATING WILL MAKE IT DIFFICULT TO REALIZE THESE CONDITIONS ON A
WIDESPREAD BASIS. WITH ONE HOUR FLASH FLOOD GUIDANCE PUSHING 2.50
INCHES...MOST LOCATIONS CAN TAKE ONE EVENT WITH 2-3 EVENTS NEEDED
TO GET TO FLASH FLOOD CRITERIA. RAP 305K ISENT MOISTURE
CONVERGENCE SUGGESTS RECENT POST FRONTAL CONVECTIVE DEVELOPMENT
OVER NW IA WILL CONTINUE THROUGH MIDNIGHT...BUT HAVE OPTED FOR
TARGETED SPS ISSUANCES RATHER THAN MORE WIDESPREAD FLASH FLOOD
WATCH FOR REASONS ALSO NOTED IN SHORT TERM SECTIONS BELOW.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 329 PM CDT SUN AUG 16 2015
SFC COLD FRONT IS SINKING SLOWLY THROUGH SOUTHEAST SOUTH DAKOTA AND
SOUTHWEST MINNESOTA THIS AFTERNOON. A WEAK UPPER RIDGE REMAINS
STRETCHED THROUGH CENTRAL IOWA AND IS SEPARATING THE MUCH DRIER AIR
TO THE SOUTHEAST FROM THE DEEPER MOISTURE TO THE WEST AND NORTHWEST
OF THE SYSTEM. THE RIDGE WILL SHIFT SOUTHEAST AND WEAKEN FURTHER
OVERNIGHT ALLOWING THE SFC BOUNDARY TO ENTER NORTHERN IOWA. THE
OVERALL FORCING AND INSTABILITY OVERNIGHT IS LIMITED AND DESPITE A
RELATIVELY WEAK LOW LEVEL JET...THE MOISTURE TRANSPORT LIFTING INTO
THE BOUNDARY IS GOOD AND WILL HELP PUSH PWATS TO NEAR 2 INCHES OVER
NORTHERN IOWA. WARM CLOUD DEPTHS AROUND 13 KFT ARE SUPPORTIVE OF AN
EFFICIENT RAIN PRODUCING ENVIRONMENT AND MEAN STORM MOTIONS ARE
CLOSE TO PARALLEL TO THE SFC BOUNDARY LEADING TO THE POTENTIAL FOR
TRAINING STORMS.
GIVEN ALL OF THE ABOVE...DO EXPECT SOME AREAS WITH HEAVY RAINFALL
POSSIBLY EXCEEDING 3 INCHES. PLANNING TO HOLD OFF ON A FLASH FLOOD
WATCH AT THIS TIME FOR A VARIETY OF REASONS. MUCH OF NORTHERN IOWA
NORTH OF HIGHWAY 20 HAVE HAD ONE HALF INCH OR LESS OF PRECIPITATION
FOR AUGUST. THE CROPS ARE NEARING FULL MATURATION AND LIMIT RUNOFF
RATES AND THE AREA WITH THE GREATEST THREAT FOR HEAVY RAIN OVER THE
FAR NORTHWEST ARE CLIMATOLOGICALLY DIFFICULT TO FLASH FLOOD DUE TO
THE LANDSCAPE. WILL MENTION LOCALIZED FLASH FLOODING POSSIBLE IN THE
HWO. SHOULD THE THREAT FOR HIGHER QPF ARISE...THEN HEADLINES MAY BE
REQUIRED. THE SEVERE WEATHER THREAT IS LOW...GIVEN THE DEEPER WARM
CLOUD DEPTHS AND SATURATED PROFILES...THE HAIL THREAT WILL BE LOW
LEAVING AN ISOLATED DAMAGING WIND GUST AS THE PRIMARY SEVERE THREAT.
.LONG TERM /MONDAY THROUGH SUNDAY/...
ISSUED AT 329 PM CDT SUN AUG 16 2015
CURRENTLY HAVE AN AREA OF LOW PRESSURE CENTERED ACROSS SRN MANITOBA
AND SASKATCHEWAN...THIS WILL PUSH INTO SOUTHERN ONTARIO SUNDAY
EVENING WITH THE ASSOCIATED COLD FRONT TO PUSH INTO NORTHWESTERN
IOWA AND THE NORTHWESTERN CWA BY LATE SUNDAY. THE FRONTAL BOUNDARY
WILL CONTINUE TO PUSH SOUTHWARD ACROSS THE CWA...STALLING OUT ACROSS
THE AREA BY LATER MONDAY INTO TUESDAY. THIS WILL ALLOW FOR AN
EXTENDED PERIOD OF RAIN CHANCES BEGINNING MAINLY LATE SUNDAY
AFTERNOON NORTHWEST AND SPREADING ACROSS THE CWA SUNDAY NIGHT INTO
MONDAY. THETA-E ADVECTION BETTER ACROSS THE NORTH INTO THE
EVENING...WITH MOISTURE CONVERGENCE INCREASING ALONG THE FRONT INTO
THE LATE NIGHT HOURS. WITH THE GRADUAL MOVEMENT IN THE FRONT...AND
MID LEVEL FLOW PARALLEL TO THE BOUNDARY...TRAINING OF STORMS IS
POSSIBLE. PWATS ALSO HIGH IN THE 1.9 TO 2 INCH RANGE...FURTHERING
HEAVY RAIN CHANCES. HOWEVER THIS AREA HAS BEEN DRIER AND FFG IS
HOVERING AROUND 3 INCHES OR JUST BELOW FOR 3 HOURS...THEREFORE THE
FLASH FLOOD THREAT IS MINIMIZED SOME.
AN UPPER LEVEL TROUGH WILL DIG INTO THE WESTERN US WITH A WEST TO
SOUTHWEST FLOW PATTERN SETTING UP TOWARD MID WEEK. A STRONGER AREA
OF LOW PRESSURE IS EXPECTED TO LIFT OUT OF THE SOUTHERN HIGH PLAINS
THROUGH IOWA AND INTO THE GREAT LAKES TUESDAY INTO WEDNESDAY. THIS
SYSTEM WILL EJECT ENERGY INTERACTING WITH THE LINGERING BOUNDARY
BRINGING THE NEXT WIDESPREAD CHANCES FOR PRECIPITATION TO MUCH OF
THE STATE. SHEAR PARAMETERS ALSO INCREASE WITH THE APPROACHING AREA
OF LOW PRESSURE ALLOWING FOR SEVERE WEATHER CHANCES AS WELL. WRAP-
AROUND PRECIP POSSIBLE INTO WEDNESDAY/WEDNESDAY NIGHT WITH HIGH
PRESSURE TO BUILD INTO THE AREA BY THURSDAY/FRIDAY. THIS SHOULD
ALLOW THE AREA TO DRY OUT BY THE END OF THE WEEK BEFORE PRECIP
CHANCES RETURN FOR THE WEEKEND WITH ANOTHER UPPER LEVEL TROUGH
PUSHING EAST FROM THE ROCKIES AND THROUGH THE NORTHERN PLAINS.
MODELS IN DISAGREEMENT OVER HOW FAR NORTH THIS SYSTEM WILL
TRACK...WITH THE EC MORE BULLISH KEEPING IT FURTHER SOUTH WHICH
WOULD BE MORE OF AN IMPACT TO THE CWA VERSUS THE GFS WHICH KEEPS THE
MAIN TROUGH ACROSS SOUTHERN CANADA.
TEMPERATURES EXPECTED TO BE HOT AND HUMID SUNDAY AS DEWPOINTS
INCREASE AHEAD OF THE COLD FRONT AND H85 TEMPS PUSH INTO THE LOW 20S
CELSIUS IN SOUTHERLY TO SOUTHWESTERLY FLOW. TEMPS TO DROP INTO THE
MID TEENS CELSIUS AS THE FRONT SAGS SOUTH...WITH COOLER TEMPS FOR
MUCH OF THE WEEK. TEMPS EXPECTED TO RETURN TO THE 80S AS SOUTHERLY
FLOW WARMS THINGS BACK UP AGAIN FRIDAY INTO SATURDAY AHEAD OF THE
UPPER LEVEL TROUGH.
&&
.AVIATION...17/06Z
ISSUED AT 1231 AM CDT MON AUG 17 2015
CONFIDENCE IS LOW THROUGH THE PERIOD WITH SHOWERS AND STORMS
POSSIBLE THE ENTIRE TIME...AND AN INCREASED POTENTIAL FOR STRATUS
NORTH LATE. HAVE PLAYED THUNDER AND CATEGORY RESTRICTIONS
SOMEWHAT CONSERVATIVE DEPENDING ON NEAR TERM TRENDS. WILL LEAVE
BROADER VICINITY WORDING UNTIL CONFIDENCE INCREASES ON THE ORDER
OF HOURS. MODELS SUGGEST LOWERING CIGS WITH SAGGING FRONT AND
OUTFLOW BOUNDARIES...ALONG WITH PROLONGED PERIOD OF SCATTERED
PRECIP.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...DONAVON
LONG TERM...BEERENDS
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS WICHITA KS
318 AM CDT MON AUG 17 2015
.SYNOPSIS...
ISSUED AT 317 AM CDT MON AUG 17 2015
CONVECTION IS DECREASING IN AREAL EXTENT BUT CONTINUING ACROSS
SOUTHWEST KANSAS AND OVER NORTH CENTRAL KANSAS AND NORTHEAST INTO
SOUTHEAST NEBRASKA. THIS SCATTERED CONVECTION IS EXPECTED TO
LINGER...BUT DIMINISH INTO THE EARLY MORNING HOURS.
BILLINGS WRIGHT
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
TODAY - TONIGHT: THE HIGH RESOLUTION GUIDANCE HRRR AND THE HIGHER
RESOLUTION NAM12 STRUGGLE TO SHOW MUCH CONVECTION PERSISTING
ACROSS CENTRAL KANSAS DURING THE EARLY PART OF THE DAY. A PIECE
OF ENERGY WILL APPROACH THE AREA FROM THE NORTHWEST DURING THE
LATE AFTERNOON HOURS WHICH WILL INCREASE THE CHANCES FOR
CONVECTION INTO THE EVENING ESPECIALLY OVER CENTRAL AND SOUTH
CENTRAL KANSAS. SHEAR WILL BE LACKING...BUT THERE IS A MODEST
1000-1500 J/KG CAPE FOR THUNDERSTORMS TO POTENTIALLY BE
STRONG...AND WITH THE WEAK FLOW...FLOODING COULD BE A CONCERN AS
WELL. MOISTURE TRANSPORT INCREASES DURING THE OVERNIGHT HOURS
INCREASING THE PRECIPITATION CHANCES FOR SOUTH CENTRAL KANSAS.
TUESDAY - WEDNESDAY:
THE STRONGER UPPER LEVEL WAVE WILL MOVE INTO THE REGION DURING THE
DAY TUESDAY...BUT THE MAIN FRONTAL PUSH WILL BE LATER TUESDAY
EVENING WHEN THE UPPER LOW DIGS SLIGHTLY DEEPER. THE UPPER PV
ENERGY MOVING ACROSS THE AREA TUESDAY WILL INCREASE THE CHANCE
FOR THUNDERSTORMS THROUGHOUT THE DAY. THE UPPER WAVE WILL BE
CLOSER TO KANSAS INCREASING THE UPPER SHEAR PROFILE. SEVERE STORMS
MAY BE POSSIBLE ESPECIALLY OVER CENTRAL AND NORTHERN PORTIONS OF
SOUTH CENTRAL KANSAS WHERE THE COMBINATION OF SHEAR AND
INSTABILITY ARE ANTICIPATED TO BE THE GREATEST. ELSEWHERE STORMS
COULD BE STRONG.
BY TUESDAY NIGHT THE MAIN COLD FRONT/WIND SHIFT WILL BEGIN MOVING
ACROSS CENTRAL AND EASTERN KANSAS. THUNDERSTORMS ALONG THE FRONT
ARE POSSIBLE...BUT THE CONVERGENCE ISN`T OVERWHELMING. THE FRONT
IS EXPECTED TO BE FAIRLY PROGRESSIVE AND MOVE THROUGH THE AREA BY
EARLY MORNING WEDNESDAY. A FEW STRONGER STORMS REMAIN POSSIBLE
ALONG THE FRONT.
A SECONDARY PIECE OF ENERGY WILL MOVE SOUTHWARD INTO THE UPPER LOW
CAUSING THE POTENTIAL FOR SCATTERED SHOWERS DURING THE DAY
WEDNESDAY.
THE FRONT WILL CAUSE TEMPERATURES ON WEDNESDAY TO BE SIGNIFICANTLY
COOLER THAN RECENT DAYS...STEADILY COOLING FROM A HIGH CLOSE TO
NORMAL TODAY IN THE LOW 90S TO THE LOW TO MID 70S BY WEDNESDAY.
BILLINGS WRIGHT
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
WHILE THERE ARE SOME SLIGHT DISCREPANCIES AMONGST THE MEDIUM
RANGE GUIDANCE...THE PATTERN REMAINS ACTIVE AND GENERALLY IN
FAIRLY GOOD AGREEMENT. ZONAL FLOW WILL RETURN BRIEFLY AHEAD OF THE
NEXT SYSTEM FOR THE WEEKEND...BUT BEFORE THAT A WEAK TROUGH WILL
IMPACT THE AREA FOR THE END OF THE WEEK.
THE WEAK TROUGH MAY BRING CHANCES FOR RAIN THURSDAY NIGHT AND
FRIDAY...BUT CONFIDENCE IS LOWER DUE TO DISCREPANCIES.
TEMPERATURES WILL STEADILY INCREASE BACK INTO THE 80S...BUT THE
NEXT FRONT WILL APPROACH AND TRAVERSE THE AREA SATURDAY
NIGHT/SUNDAY MORNING. THIS FRONT WILL BRING THE NEXT BEST CHANCE
OF RAIN TO THE REGION. THIS PERIOD HAS HIGHER CONFIDENCE DUE TO
BETTER AGREEMENT ACROSS VARIOUS MODEL SOLUTIONS.
BILLINGS WRIGHT
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1105 PM CDT SUN AUG 16 2015
A RELATIVELY LIGHT SOUTHEAST-SOUTHERLY WIND COMPONENT SHOULD
PREVAIL OVERNIGHT INTO MONDAY...TO THE SOUTH OF A FRONTAL
BOUNDARY...EXTENDING FROM FAR SOUTHEAST NEBRASKA ACROSS
NORTHWESTERN KANSAS. SCATTERED WEAK ELEVATED CONVECTION IS
POSSIBLE MONDAY MORNING...ALONG/W OF HIGHWAY 14 IN AN AREA OF
WEAK MOISTURE TRANSPORT. OTHERWISE...BETTER CHANCES FOR
THUNDERSTORMS WILL BE MONDAY NIGHT...AS A WEAK SHORTWAVE EJECTS
OUT OF COLORADO...IN COMBINATION WITH A SOUTHERLY LOW-LEVEL JET
AND ASSOCIATED MOISTURE TRANSPORT.
JMC
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 90 70 86 62 / 10 40 60 70
HUTCHINSON 91 70 86 59 / 20 40 60 60
NEWTON 90 69 85 60 / 10 40 60 70
ELDORADO 91 70 85 61 / 10 40 60 70
WINFIELD-KWLD 92 71 86 63 / 10 40 60 70
RUSSELL 88 67 83 55 / 40 50 60 40
GREAT BEND 89 68 85 56 / 30 50 60 40
SALINA 90 69 85 59 / 30 40 60 60
MCPHERSON 90 69 85 59 / 20 40 60 60
COFFEYVILLE 92 71 86 65 / 10 30 60 70
CHANUTE 91 70 85 64 / 10 30 60 70
IOLA 91 70 84 63 / 20 30 60 70
PARSONS-KPPF 92 71 85 64 / 10 30 60 70
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1153 PM MDT SUN AUG 16 2015
.UPDATE...
ISSUED AT 928 PM MDT SUN AUG 16 2015
UPDATED THE FORECAST FOR TONIGHT BASED ON LATEST RADAR TRENDS AND
MODEL DATA. CURRENT LINE OF STORMS SHOULD BE SOUTH OF THE AREA BY
MIDNIGHT OR SHORTLY AFTER. OVERNIGHT ANOTHER ROUND OF STORMS MAY
MOVE ACROSS THE NORTHERN PART OF THE AREA. HOWEVER AM SOMEWHAT
DOUBTFUL OF THIS SINCE THAT IS BEHIND THE COLD FRONT AND ANY
STORMS THAT HAVE TRIED TO MOVE OVER THE AREA BEHIND THE FRONT HAVE
NOT SURVIVED. LOWERED CHANCES OVERNIGHT SOME TO ACCOUNT FOR THIS
BUT STILL KEPT A MENTION OF RAIN GOING.
UPDATE ISSUED AT 847 PM MDT SUN AUG 16 2015
THE STORM ACTIVITY WHICH PROMPTED THE WATCH HAS MOVED OUT OF THE
WATCH AREA. IN ADDITION NO FURTHER HEAVY RAIN DEVELOPMENT IS
EXPECTED THROUGH THE REST OF THE NIGHT.
UPDATE ISSUED AT 700 PM MDT SUN AUG 16 2015
UPDATED FORECAST TO ACCOUNT FOR STORMS BEING TIED TO THE COLD
FRONT AS IT IS PUSHED SOUTHWARD. EXPECT THESE STORMS TO MOVE
SOUTH THROUGH THE REST OF THE AREA THIS EVENING...AND BE SOUTH OF
THE AREA AN HOUR OR SO AFTER MIDNIGHT.
BEHIND THE FRONT THE COOLER AIR AND LACK OF LIFT HAVE SERVED TO
END ANY STORMS THAT LINGER TOO LONG BEHIND THE FRONT. DO EXPECT
THE STORM ACTIVITY EAST OF HIGHWAY 25 TO CONTINUE INTO MID
EVENING BEFORE MOVING EAST OF THE AREA DUE TO THE NOSE OF THE LOW
LEVEL JET HELPING TO SUSTAIN THOSE STORMS.
TO THE WEST ANOTHER AREA OF STORMS IS SLOWLY MOVING TOWARD THE
AREA. HAVE NOTICED THE LEADING LINE OF STORMS HAS DISSIPATED AS
THEY ENCOUNTER THE FRONT. MODELS SHOW SOME ISENTROPIC OVER THE
WESTERN PORTIONS OF THE AREA...SO WILL HAVE HIGHER CHANCES FOR
RAIN THERE DECLINING TO THE EAST.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 16 2015
WV IMAGERY AND RAP ANALYSIS SHOWS RIDGE CENTERED OVER SOUTHERN
CALIFORNIA WITH AXIS EXTENDING ACROSS THE HIGH PLAINS AND INTO THE
GREAT LAKES REGION. PLUMES OF MID LEVEL MOISTURE ORIGINATING IN THE
PACIFIC ARE ROTATING AROUND THE EASTERN AND NORTHERN PERIPHERY OF THE
LARGE SCALE RIDGE INTO THE ROCKIES AND HIGH PLAINS. DIFFLUENT FLOW IS
CURRENTLY IN PLACE ACROSS THE CENTRAL ROCKIES WITH TROUGH DIGGING
INTO THE NORTHERN PLAINS. A FEW WEAKER SHORTWAVE TROUGHS ARE JUST TO
THE WEST/NORTHWEST OF OUR CWA. AT THE SURFACE QUASI-STATIONARY FRONT
CURRENTLY EXTENDS ACROSS CENTRAL NEBRASKA INTO NORTHCENTRAL COLORADO
OVER THE FAR NORTHWEST PART OF OUR CWA. PREFRONTAL TROUGH AXIS IS IN
PLACE FROM SOUTHEAST COLORADO OVER GOODLAND AND NORTON KANSAS.
THIS AFTERNOON-TONIGHT...THUNDERSTORM ACTIVITY SHOULD INITIATE
WITHIN THE NEXT FEW HOURS ALONG FRONT AND SURFACE TROUGH WITH
COVERAGE INCREASING THIS EVENING AS A SERIES OF WEAK SHORTWAVE
TROUGHS ROTATE ACROSS THE REGION. RECENT TRENDS IN ARW/NMM HAVE BEEN
TO SHIFT MOST ORGANIZED THUNDERSTORM CLUSTER TO THE SOUTH ROUGHLY
ALONG AND SOUTH OF INTERSTATE 70. CURRENTLY THE ORIENTATION OF FLOW
ALOFT AND OTHER GUIDANCE STILL SHOWING THUNDERSTORM CLUSTERS
ORIGINATING FROM THE WEST OR NORTHWEST OF THIS. EITHER WAY...DEEP
MOIST AIR MASS AND DECENT INSTABILITY AHEAD OF FRONT WILL SUPPORT
ACTIVITY ACROSS MUCH OF CWA TRANSITIONING EASTWARD. STRONGEST CAPE
AXIS IF FURTHER EAST THAN PREVIOUS GUIDANCE INDICATED...THOUGH THERE
IS ENOUGH ELEVATED CAPE TO AT LEAST CONSIDER POTENTIAL FOR
MARGINALLY SEVERE HAIL. DCAPE 1000-1500 J/KG COINCIDING DRY ADIABATIC
PROFILES BELOW 700MB COULD SUPPORT ISOLATED SEVERE DOWNDRAFT
POTENTIAL DURING THE AFTERNOON...THOUGH AS MIXING RATIOS INCREASE
BELOW 700MB THIS EVENING THIS THREAT WILL LIKELY DIMINISH.
REGARDING FLASH FLOOD WATCH...ANOMALOUSLY HIGH PWAT VALUES 1.2-1.6
WILL ONLY INCREASE THROUGH THE NIGHT APPROACHING 1.7-1.8 WHICH IS
WELL WITHIN 99TH PERCENTILE OR 3 STANDARD DEVIATIONS FROM NORMAL.
WITH VERY SLOW STORM MOTIONS AND POSSIBILITY FOR
TRAINING/BACKBUILDING I AM COMFORTABLE WITH FLASH FLOOD WATCH. IF
ARW/NMM SOLUTION PANS OUT THEN WE MAY NEED TO CONSIDER ADDING
SOUTHERN PART OF FORECAST AREA TO WATCH.
MONDAY...WHILE FRONTAL PASSAGE SHOULD OCCUR FROM NORTH TO SOUTH
MONDAY...GUIDANCE IS SHOWING A LOT OF SPREAD ON TIMING. THIS LOWERS
CONFIDENCE/TIMING OF ADDITIONAL THUNDERSTORM ACTIVITY. ARW/NMM SHOW
A MORE ORGANIZED THUNDERSTORM CLUSTER DEVELOPING ALONG FRONT MONDAY
MORNING...THOUGH OTHER GUIDANCE IS SHOWING PREDOMINANTLY ISOLATED TO
SCATTERED ACTIVITY LINGERING ACROSS THE AREA. DEEP MOIST LAYER
REMAINS IN PLACE...SO WITH POTENTIAL FOR OVERRUNNING ALONG BAROCLINIC
ZONE...IT IS POSSIBLE FOR A MORE ORGANIZED CLUSTER IF WE CONTINUE TO
SEE WEAK HEIGHT FALL...WHICH COULD ALSO RESULT CONTINUING THREAT FOR
FLASH FLOODING. SEVERE THUNDERSTORM THREAT WILL BE HIGHLY DEPENDENT
ON FRONTAL POSITION/TIMING AS BETTER INSTABILITY WILL TEND TO BE
AHEAD OF FRONT. AS WITH TODAY...THREATS WOULD BE LARGE HAIL/DAMAGING
WINDS ALONG/SOUTH OF FRONT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 252 PM MDT SUN AUG 16 2015
FOR THIS EXTENDED FORECAST PACKAGE...A STRONG COLD FRONT IS EXPECTED
TO MOVE THROUGH ON TUESDAY...BRINGING AN END TO SIGNIFICANT
PRECIPITATION CHANCES AND A TEMPORARY PARDON FROM THE WARMTH AND
HUMIDITY. ZONAL FLOW ALOFT RETURNS BEHIND TUESDAY`S SYSTEM. WITH
SOUTHERLY LOW LEVEL FLOW...A WARMING TREND IS EXPECTED TO BEGIN
THURSDAY. HOWEVER...YET ANOTHER UPPER LEVEL DISTURBANCE IS EXPECTED
TO FORCE A COLD FRONT THROUGH THIS WEEKEND...BRINING ANOTHER CHANCE
FOR BELOW NORMAL TEMPERATURES.
THE MOST IMPACTFUL WEATHER IN THE EXTENDED FORECAST PERIOD IS
ANTICIPATED MONDAY EVENING THROUGH TUESDAY EVENING. ACTIVE WEATHER
IS FORECAST AS A LARGE NEGATIVELY TILTED TROUGH KICKS OUT OVER THE
HIGH PLAINS. STRONG/SEVERE THUNDERSTORMS MAY BE ONGOING ACROSS
PORTIONS OF THE REGION MONDAY EVENING DEPENDING ON THE FRONT
LOCATION AND ENVIRONMENTAL PARAMETERS. ANY POTENTIAL SEVERE WEATHER
THREAT MAY BE HIGHER MONDAY EVENING AS INITIAL DEVELOPMENT IN
COLORADO SHOULD BE MOVING IN. THE PRIMARY THREATS FOR SEVERE WEATHER
WILL BE LARGE HAIL AND DAMAGING WINDS. AS MENTIONED IN THE DAY 2
STORM PREDICTION CENTER OUTLOOK...SURFACE VORTICITY/HELICITY
MAXIMIZED IN THE VICINITY OF THE FRONT MAY PROVIDE AN OPPORTUNITY
FOR A TORNADO TO OCCUR. CONFIDENCE IN THIS ISN`T AS HIGH AS HIGHER
RESOLUTION GUIDANCE INDICATES THE POTENTIAL FOR COLD POOL
DEVELOPMENT...HIGHLIGHTING A HIGHER THREAT OF MCS DEVELOPMENT WITH
DAMAGING WINDS AS THE MAIN THREAT. IN TERMS OF FLASH FLOODING...A
THREAT WILL STILL EXIST ESPECIALLY IF HEAVY RAINS ARE RECEIVED
TONIGHT. PRECIPITABLE WATER VALUES FALL AS THE FRONT DOES FORCE SOME
MOISTURE SOUTH SO WE NO LONGER EXPECT PRECIPITABLE WATER VALUES
NEARING THE 99TH PERCENTILE. STORM MOVEMENT REMAINS QUITE SLOW IN
TERMS OF STEERING WINDS ALOFT SO COLD POOL FORMATION/MOVEMENT SHOULD
BE THE PRIMARY DRIVER. THEREFORE...A FLASH FLOOD THREAT MAY PERSIST
AND ANOTHER FLASH FLOOD WATCH MAY BE NEEDED FOR MONDAY EVENING IN
LATER FORECAST PACKAGES.
ON TUESDAY...THE FRONT SHOULD FINALLY SLIDE ALL THE WAY THROUGH THE
REGION...RESTRICTING HIGHEST INSTABILITY SOUTH OF THE FRONT AND
PRIMARILY SOUTH OF THE REGION. HOWEVER...CONFIDENCE IS LOW ON WHEN
THIS COLD FRONT WILL SURGE SOUTH AND THERE MAY BE ENOUGH TIME FOR
STORM DEVELOPMENT AHEAD OF THE FRONT. THIS WOULD MEAN SEVERE WEATHER
IS POSSIBLE BUT UNLIKELY TUESDAY. HOWEVER...ADDITIONAL PERTURBATIONS
MOVE IN FROM THE NORTHWEST BEHIND THE MAIN FORCING AND WITH SOME
INSTABILITY REMAINING IN THE POST-FRONTAL ENVIRONMENT...THERE SHOULD
BE ADDITIONAL SHOWER/THUNDERSTORM DEVELOPMENT TUESDAY AFTERNOON BUT
COVERAGE AND INTENSITY REMAINS IN DOUBT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1148 PM MDT SUN AUG 16 2015
VFR TO IFR CONDITIONS FORECAST FOR THE 6Z TAFS. LATEST SURFACE
OBSERVATIONS FOR CENTRAL NEBRASKA SHOW LIGHT FOG/IFR CEILINGS
MOVING SOUTHWEST WITH THE LIGHT NORTH WIND. LATEST MODEL DATA HAS
SUPPORTED THESE CONDITIONS MOVING OVER THE TAFS SITES HAVE
LOWERED VISIBILITIES/CEILING ACCORDINGLY. EXPECT THE LOWEST
VISIBILITY TO BE AROUND SUNRISE AS IS TYPICAL. DURING THE MORNING
THE LOW CLOUDS WILL BE VERY SLOW TO LIFT BUT SHOULD BY LATE
MORNING OR EARLY AFTERNOON.
OVERNIGHT THERE WILL BE A CHANCE FOR SOME STORMS TO MOVE OVER
MAINLY KMCK. AT THIS TIME COVERAGE IS TOO SPARSE TO PLACE IN THE
TAF BUT THE BEST TIME LOOKS TO BE AFTER 8Z. COULD BE SOME STORMS
NEAR KMCK MONDAY MORNING BUT WILL KEEP ANY MENTION OUT FOR NOW DUE
TO UNCERTAINTY THAT COVERAGE WILL BE ENOUGH TO WARRANT A MENTION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...DR
LONG TERM...RRH
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
320 AM EDT MON AUG 17 2015
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
MOISTURE WILL CONTINUE TO ADVECT INTO THE REGION FROM THE SOUTH THIS
PERIOD. AN UPPER LEVEL LOW NOW ALONG THE SOUTHERN IN/IL BORDER WILL
TRAVEL NORTH AND THEN START HEADING NORTHEAST BY LATER THIS
AFTERNOON. ALREADY SEEING SOME LIGHT RADAR RETURNS OVER SOUTH
CENTRAL TN THIS HOUR...IN AN AREA OF ENHANCED LIFT ON THE SOUTH SIDE
OF A WEAK UPPER JET. THESE RAINS SHOULD LIFT NORTHWARD THIS MORNING.
ANOTHER AREA OF SHOWERS SHOULD DEVELOP ALONG THE OHIO RIVER THIS
MORNING...WHERE THE LATEST RAP PLACES A THETA-E RIDGE.
THE CHANCE FOR AFTERNOON THUNDERSTORMS WILL DEPEND PARTLY ON HOW
MANY BREAKS WE GET IN THE CLOUDS TODAY. IT WILL NOT TAKE MUCH...AS
COOLER AIR ALOFT WITH THE PASSAGE OF THE UPPER LOW WILL MEAN SOME
ELEVATED INSTABILITY AS WELL. GIVEN THE CLOUD COVER THOUGH...THINK
THE RISK FOR SEVERE WEATHER IS FAIRLY LOW.
TONIGHT THAT WAVE SHOULD BE HEADING TOWARD NORTHERN OHIO. THAT SAID
THOUGH...IT WILL LEAVE A TRAILING TROUGH THAT MAY ALLOW FOR
CONTINUED STORM DEVELOPMENT OVER THE SOUTHEAST HALF OF OUR FORECAST
AREA. THAT AREA WILL CONTINUE TO SEE THE BEST CHANCES ON TUESDAY.
MAY HAVE TO MONITOR FOR FLOOD THREAT DOWN THERE AS OUR SOUTHEAST
COUNTIES HAVE LOWER FLASH FLOOD GUIDANCE. STILL CURRENT QPF IS WELL
BELOW THAT GUIDANCE, BUT SHOULD LATER FORECASTS TREND UP MORE WE
MAYNEED A WATCH.
CLOUD COVER SHOULD LIMIT HIGH TEMPERATURES TO BELOW NORMAL TODAY AND
TUESDAY...WHEREAS LOWS WILL BE A LITTLE ABOVE NORMAL. ONLY OTHER
CONCERN WOULD BE PATCHY FOG BOTH THIS MORNING AND TOMORROW MORNING,
WITH COVERAGE LIMITED BOTH DAYS ALSO BY CLOUD COVER.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
TUESDAY NIGHT...
WEAK SOUTHWEST FLOW WILL BE IN PLACE AHEAD OF A STRONG NORTH CENTRAL
CONUS TROUGH TO START THE LONG TERM. MAINLY DIURNALLY DRIVEN
SCATTERED T-STORMS ARE EXPECTED TO BE ONGOING ACROSS OUR SE CWA
TUESDAY EVENING, HOWEVER THESE SHOULD GRADUALLY DIMINISH AS WE HEAD
INTO THE OVERNIGHT HOURS. CAN`T GO COMPLETELY DRY AS THERE IS A
SIGNAL FOR SOME LOW LEVEL JETTING THROUGH THE OVERNIGHT. SOUTHERLY
WINDS SHOULD INCREASE TOWARD DAWN, HELPING LOWS TO STAY ON THE MILD
SIDE. LOOK FOR MAINLY LOW 70S.
WEDNESDAY - THURSDAY...
STRONG SHORTWAVE TROUGH AND ITS ASSOCIATED SURFACE LOW WILL MOVE
FROM THE UPPER MIDWEST TO LAKE SUPERIOR BY LATE WEDNESDAY NIGHT.
DEEP MOISTURE WILL POOL INTO THE OHIO RIVER VALLEY AHEAD OF THE
TROUGH AND SURFACE FRONT TRAILING FROM THE LOW. MEANWHILE, STRONGER
DEEP FLOW WILL ALSO OVERSPREAD THE REGION BY WEDNESDAY NIGHT. LOOK
FOR SCATTERED TO NUMEROUS THUNDERSTORMS DURING THE DAY ON WEDNESDAY
WITH HIGHS MAINLY IN THE LOW 80S. A FEW OF THE STORMS COULD BE
STRONG IF MODERATE INSTABILITY IS REALIZED, ALTHOUGH BETTER DEEP
SHEAR AND FORCING DOESN`T ARRIVE UNTIL LATER WEDNESDAY NIGHT. WE`LL
HAVE TO CONTINUE TO KEEP AN EYE ON POTENTIAL FOR AN ORGANIZED SEVERE
THREAT LATER WEDNESDAY EVENING INTO WEDNESDAY NIGHT, ALTHOUGH SOME
LIMITING FACTORS COULD BE TIMING OF PASSAGE/MORE LIMITED INSTABILITY
AND BEST FORCING NORTH OF THE CWA. WILL CONTINUE TO MENTION HEAVY
RAIN AND GUSTY WINDS AS THE MAIN POTENTIAL THREATS IN THE HWO.
COLD FRONT LOOKS TO PASS THROUGH EARLY THURSDAY MORNING ACROSS THE
NW AND THROUGH MOST OF THE CWA BY LATE THURSDAY MORNING. IF PASSAGE
IS SLOW ENOUGH, SOME REDEVLOPMENT COULD OCCUR ACROSS OUR FAR E OR SE
THURSDAY AFTERNOON, WHERE SOME STRONGER/PULSY STORMS WOULD BE
POSSIBLE. OTHERWISE, SKIES WILL BECOME GRADUALLY CLEARER WITH
TEMPERATURES ONLY TOPPING OUT IN THE MID OR UPPER 70S.
THURSDAY NIGHT - SUNDAY...
THE FRONT COULD HANG UP ACROSS OUR SOUTH TO END THE WEEK AND HEAD
INTO THE WEEKEND SO WILL KEEP ISOLATED TO WIDELY SCATTERED CHANCES
ACROSS THE SOUTH THROUGH SATURDAY. THE NORTH WILL BE DRY DURING THIS
TIME CLOSER TO THE SURFACE HIGH CENTER. THURSDAY NIGHT LOWS LOOK TO
DROP INTO THE UPPER 50S NORTH AND LOWER 60S SOUTH THURSDAY NIGHT.
CAN`T RULE OUT A FEW MID 50S IN OUR TYPICAL COOL NORTH SPOTS. HIGHS
ON FRIDAY WILL MODERATE A BIT, FINDING THEIR WAY BACK TO THE LOW
80S. FRIDAY NIGHT WILL BE SLIGHTLY MILDER WITH LOWS BACK IN THE LOW
AND MID 60S. SATURDAY BRINGS HIGHS IN THE LOW AND MID 80S.
STORM CHANCES MAY INCREASE ON SUNDAY AHEAD OF ANOTHER MID LEVEL
DISTURBANCE AND ASSOCIATED SURFACE FRONT. HOWEVER, CONFIDENCE IS LOW
IN TIMING OF THIS FEATURE SO WILL ONLY MENTION LOW CHANCES AT THIS
TIME.
&&
.AVIATION (06Z TAF UPDATE)...
ISSUED AT 140 AM EDT MON AUG 17 2015
IMPRESSIVE PLUME OF MOISTURE STREAMING IN AND WRAPPING INTO AN UPPER
LOW CENTERED OVER THE WABASH VALLEY. NOT QUITE SEEING ANY RAIN FORM
OUT OF THIS FLOW BUT IT SHOULD START IN FROM THE SOUTH BY
DAYBREAK...WITH THE BEST CHANCE FOR SHOWERS AT KBWG BY 11Z. SOME
LIGHT VSBY RESTRICTIONS MAY PRECEDE THAT BASED ON RAIN THAT FELL
THERE YESTERDAY. TIME-HEIGHT SECTIONS ARE NOT SHOWING AS STRONG OF A
LIFT IN ASSOCIATION WITH THIS MOISTURE SO HAVE GONE WITH VICINITY
SHOWER WORDING FOR NOW...THOUGH CANNOT RULE OUT EMBEDDED OCCASIONAL
THUNDER. GUIDANCE ALSO WAS IN THE 10 PERCENT RANGE FOR LIGHTNING
ACTIVITY.
CLOUD COVER THROUGH THE DAY SHOULD LIMIT INSTABILITY...BUT WITH
DISTURBANCES RIDING AROUND THE UPPER LOW CANNOT RULE OUT SOME STORMS
THIS AFTERNOON...SO WENT WITH PROB30 GROUPS FOR ALL SITES. LOW
CLOUDS SHOULD FILL IN BY LATE IN THE PERIOD...WITH MVFR RESTRICTIONS
POSSIBLE.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........RJS
LONG TERM.........BJS
AVIATION..........RJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
538 AM EDT MON AUG 17 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN UPPPER
MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN AND UPPER
LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET OVER NW
ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER MI. THE
AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG LINGERED OVER
THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO NEAR 40 KNOTS
SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN CWA OVERNIGHT
NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCPAE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAI WITH MAX TEMPS IN THE
LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW TO THE
LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT MON AUG 17 2015
SEASONABLY COOL WEATHER WILL PREVAIL FOR THE MIDDLE OF THE WEEK
AMIDST RAIN. TEMPS WILL INCH BACK TO ABOVE AVERAGE BY SATURDAY
BEFORE A COLD FRONT BRINGS A CHANCE FOR RAIN AND ANOTHER COOL-DOWN
ON SUNDAY.
TUESDAY...DEEP MID-LEVEL TROUGHING WILL BE ONGOING ACROSS THE
NORTHERN AND CENTRAL PLAINS BY TUESDAY MORNING...WITH A LEE CYCLONE
FORMING OVER THE CENTRAL HIGH PLAINS. MEANWHILE...THE COLD FRONT
THAT CROSSED THE AREA EARLIER TODAY WILL HAVE WASHED OUT ACROSS
NORTHERN WI...WITH THE H7 TO H8 FRONT LINGERING AS FAR NORTH AS THE
SOUTH-CENTRAL CWA. WIDESPREAD WAA AHEAD OF THE DEVELOPING LOW LOOKS
TO HOLD OFF UNTIL TUESDAY NIGHT...THOUGH MID-LEVEL FGEN BECOMES
APPARENT BY THE AFTERNOON. WITH MODELS BEGINNING TO BACK OFF ON THE
SOUTHWARD PUSH OF DEEP DRY AIR BEHIND THE FRONT TODAY...THINK THAT
AT LEAST SOME LIGHT RAIN WILL BE POSSIBLE BY TUESDAY AFTERNOON.
GIVEN THAT WAA/ISENTROPIC LIFT IS STILL MINIMAL...CONTINUED WITH
JUST SLIGHT CHANCES IN THE FORECAST.
TUESDAY NIGHT AND WEDNESDAY...LOW-LEVEL MOISTURE TRANSPORT AND
ISENTROPIC LIFT QUICKLY INCREASE TUESDAY EVENING AS THE SFC LOW
STRENGTHENS AND NEARS. THE MID-LEVEL SHORTWAVE BEGINS TO TAKE ON
MORE OF A NEGATIVE TILT BY THIS TIME...SENDING MUCH OF THE MID-LEVEL
Q-VECTOR CONV NNE ACROSS MN AND WESTERN LAKE SUPERIOR.
ADDITIONALLY...THE LEFT-EXIT OF A STRENGTHENING 110KT UPPER JET
STREAK WILL PASS WEST OF THE CWA. WITH PWATS SURPASSING 1.5 IN...A
BAND OF HEAVY RAIN SHOULD DEVELOP WEST OF THE CWA...POSSIBLY
CLIPPING THE FAR WEST. MEANWHILE...STEADY LIGHT TO MODERATE RAIN
ASSOCIATED WITH THE WAA IS EXPECTED FOR THE REMAINDER OF THE CWA
THROUGH THE NIGHT. DYNAMICS ARE FAVORABLE FOR POSSIBLE THUNDER
ACROSS THE WEST...WHILE MUCAPE OF AROUND 500 J/KG WILL BE ENOUGH FOR
SOME EMBEDDED THUNDER ACROSS THE EAST.
A RATHER PRONOUNCED MID-LEVEL DRY SLOT WILL QUICKLY SPREAD ACROSS
THE CWA FROM THE SW WEDNESDAY MORNING AS THE SFC LOW TRACKS NNE
ACROSS WESTERN LAKE SUPERIOR. STEEPENING MID-LEVEL LAPSE RATES AHEAD
OF THIS DRY SLOT WILL ALLOW FOR SOME EMBEDDED THUNDERSTORMS. SHOWERS
BECOME ISOLATED ACROSS THE CENTRAL UNDER THE DRY SLOT...BUT CONTINUE
FOR THE FAR WEST AND EAST DURING THE AFTERNOON. ALSO...S TO SW WINDS
LOOK TO GET QUITE GUSTY ACROSS THE CENTRAL AND EAST AHEAD OF AND
UNDER THE DRY SLOT.
WEDNESDAY NIGHT AND THURSDAY...WRAP AROUND MOISTURE WILL KEEP RAIN
CHANCES ACROSS MOST OF THE CWA...PARTICULARLY ALONG LAKE THE WEST
WIND BELTS OF LAKE SUPERIOR...THROUGH THURSDAY BEFORE SYNOPTIC
FORCING AND MOISTURE DEPART THURSDAY NIGHT. H8 TEMPS DOWN TO 5C
COMBINED WITH A STRONG GRADIENT FLOW AND RELATIVELY WARM LAKE TEMPS
WILL ALLOW FOR VERY BREEZY WEST WINDS ON THURSDAY. GUSTS TO 40MPH
ACROSS THE KEWEENAW AND WESTERN SHORE ARE NOT OUT OF THE QUESTION.
FRIDAY THROUGH SUNDAY...WEAK MID-LEVEL CYCLONIC FLOW WILL CONTINUE
OVER THE CWA ON FRIDAY...RESULTING IN VERY SMALL CHANCES OF RAIN
WITH ANY SUBTLE EMBEDDED SHORTWAVE. WILL MAINTAIN A DRY FORECAST
GIVEN THE LITTLE CHANCE OF ANYTHING MATERIALIZING. SATURDAY LOOKS TO
BE ANOTHER WARM DAY AS MID-LEVEL RIDGING AND INCREASING H8 TEMPS
BUILD ACROSS THE UPPER GREAT LAKES. TEMPS SHOULD REACH THE 80S FOR
MOST OF THE CWA. MID-LEVEL TROUGHING GLANCING THE NORTHERN HIGH
PLAINS EARLY SATURDAY WILL RESULT IN LOW-PRESSURE DEVELOPMENT ACROSS
THE NORTHERN PLAINS AND SOUTH-CENTRAL CANADA. GUIDANCE SHOWS SOME
DIFFERENCES IN THE TIMING OF AN ASSOCIATED COLD FRONT CROSSING THE
CWA...BUT A ROUND OF SHOWERS AND STORMS SHOULD AFFECT THE AREA
SOMETIME LATE SATURDAY NIGHT THROUGH SUNDAY. EITHER WAY...GUSTY
SOUTHERLY WINDS OVER 25MPH WILL LIKELY OCCUR AHEAD OF THIS FRONT
SATURDAY INTO SUNDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 132 AM EDT MON AUG 17 2015
SOME -SHRA/PERHAPS A TS IN ADVANCE OF A COLD FNT APRCHG FM THE W WL
IMPACT MAINLY SAW DURING THE EARLY MRNG HRS. THE ARRIVAL OF DRIER
LLVL AIR WL ENSURE CONDITIONS REMAIN VFR AT CMX AND IWD EVEN IF SOME
-SHRA FALL THERE. BUT SAW COULD PICK UP MVFR CONDITIONS WITH MORE
HUMID LLVL AIR LINGERING. SINCE THE COLD FNT WL STALL JUST TO THE S
ON MON...AN UPPER DISTURBANCE TRACKING ALONG THIS BNDRY WL BRING A
CONTINUED CHC OF MORE -SHRA INTO THE AFTN AT SAW. WITH A WSHFT TO
AN UPSLOPE NNE DIRECTIN IN THE AFTN AND MORE LINGERING MSTR...MVFR
CIGS ARE LIKELY AT SAW FOR A TIME. SINCE CMX AND IWD WL BE FARTHER
FM THE FNT AND DEEPER INTO THE INCOMING DRY AIRMASS...VFR CONDITIONS
WL REMAIN THE RULE THERE THRU THE TAF PERIOD..
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EDT MON AUG 17 2015
WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH TONIGHT...THEN
NE WINDS WILL INCREASE TO UP TO 30 KNOTS TUE INTO TUE NIGHT AS A LOW
PRES SYSTEM MOVES INTO THE UPPER MS VALLEY. WINDS MAY TEMPORARILY
DIMINISH WED AS A LOW PRES SYSTEM MOVES TOWARD LAKE SUPERIOR.
HOWEVER...AS THE STRONG LOW DEPARS LATE WED NIGHT INTO THU SOME WRLY
GALE FORCE GUSTS TO 35 KNOTS ARE POSSIBLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...KC
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
531 AM EDT MON AUG 17 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN UPPPER
MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN AND UPPER
LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET OVER NW
ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER MI. THE
AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG LINGERED OVER
THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO NEAR 40 KNOTS
SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN CWA OVERNIGHT
NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCPAE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAI WITH MAX TEMPS IN THE
LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW TO THE
LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT MON AUG 17 2015
SEASONABLY COOL WEATHER WILL PREVAIL FOR THE MIDDLE OF THE WEEK
AMIDST RAIN. TEMPS WILL INCH BACK TO ABOVE AVERAGE BY SATURDAY
BEFORE A COLD FRONT BRINGS A CHANCE FOR RAIN AND ANOTHER COOL-DOWN
ON SUNDAY.
TUESDAY...DEEP MID-LEVEL TROUGHING WILL BE ONGOING ACROSS THE
NORTHERN AND CENTRAL PLAINS BY TUESDAY MORNING...WITH A LEE CYCLONE
FORMING OVER THE CENTRAL HIGH PLAINS. MEANWHILE...THE COLD FRONT
THAT CROSSED THE AREA EARLIER TODAY WILL HAVE WASHED OUT ACROSS
NORTHERN WI...WITH THE H7 TO H8 FRONT LINGERING AS FAR NORTH AS THE
SOUTH-CENTRAL CWA. WIDESPREAD WAA AHEAD OF THE DEVELOPING LOW LOOKS
TO HOLD OFF UNTIL TUESDAY NIGHT...THOUGH MID-LEVEL FGEN BECOMES
APPARENT BY THE AFTERNOON. WITH MODELS BEGINNING TO BACK OFF ON THE
SOUTHWARD PUSH OF DEEP DRY AIR BEHIND THE FRONT TODAY...THINK THAT
AT LEAST SOME LIGHT RAIN WILL BE POSSIBLE BY TUESDAY AFTERNOON.
GIVEN THAT WAA/ISENTROPIC LIFT IS STILL MINIMAL...CONTINUED WITH
JUST SLIGHT CHANCES IN THE FORECAST.
TUESDAY NIGHT AND WEDNESDAY...LOW-LEVEL MOISTURE TRANSPORT AND
ISENTROPIC LIFT QUICKLY INCREASE TUESDAY EVENING AS THE SFC LOW
STRENGTHENS AND NEARS. THE MID-LEVEL SHORTWAVE BEGINS TO TAKE ON
MORE OF A NEGATIVE TILT BY THIS TIME...SENDING MUCH OF THE MID-LEVEL
Q-VECTOR CONV NNE ACROSS MN AND WESTERN LAKE SUPERIOR.
ADDITIONALLY...THE LEFT-EXIT OF A STRENGTHENING 110KT UPPER JET
STREAK WILL PASS WEST OF THE CWA. WITH PWATS SURPASSING 1.5 IN...A
BAND OF HEAVY RAIN SHOULD DEVELOP WEST OF THE CWA...POSSIBLY
CLIPPING THE FAR WEST. MEANWHILE...STEADY LIGHT TO MODERATE RAIN
ASSOCIATED WITH THE WAA IS EXPECTED FOR THE REMAINDER OF THE CWA
THROUGH THE NIGHT. DYNAMICS ARE FAVORABLE FOR POSSIBLE THUNDER
ACROSS THE WEST...WHILE MUCAPE OF AROUND 500 J/KG WILL BE ENOUGH FOR
SOME EMBEDDED THUNDER ACROSS THE EAST.
A RATHER PRONOUNCED MID-LEVEL DRY SLOT WILL QUICKLY SPREAD ACROSS
THE CWA FROM THE SW WEDNESDAY MORNING AS THE SFC LOW TRACKS NNE
ACROSS WESTERN LAKE SUPERIOR. STEEPENING MID-LEVEL LAPSE RATES AHEAD
OF THIS DRY SLOT WILL ALLOW FOR SOME EMBEDDED THUNDERSTORMS. SHOWERS
BECOME ISOLATED ACROSS THE CENTRAL UNDER THE DRY SLOT...BUT CONTINUE
FOR THE FAR WEST AND EAST DURING THE AFTERNOON. ALSO...S TO SW WINDS
LOOK TO GET QUITE GUSTY ACROSS THE CENTRAL AND EAST AHEAD OF AND
UNDER THE DRY SLOT.
WEDNESDAY NIGHT AND THURSDAY...WRAP AROUND MOISTURE WILL KEEP RAIN
CHANCES ACROSS MOST OF THE CWA...PARTICULARLY ALONG LAKE THE WEST
WIND BELTS OF LAKE SUPERIOR...THROUGH THURSDAY BEFORE SYNOPTIC
FORCING AND MOISTURE DEPART THURSDAY NIGHT. H8 TEMPS DOWN TO 5C
COMBINED WITH A STRONG GRADIENT FLOW AND RELATIVELY WARM LAKE TEMPS
WILL ALLOW FOR VERY BREEZY WEST WINDS ON THURSDAY. GUSTS TO 40MPH
ACROSS THE KEWEENAW AND WESTERN SHORE ARE NOT OUT OF THE QUESTION.
FRIDAY THROUGH SUNDAY...WEAK MID-LEVEL CYCLONIC FLOW WILL CONTINUE
OVER THE CWA ON FRIDAY...RESULTING IN VERY SMALL CHANCES OF RAIN
WITH ANY SUBTLE EMBEDDED SHORTWAVE. WILL MAINTAIN A DRY FORECAST
GIVEN THE LITTLE CHANCE OF ANYTHING MATERIALIZING. SATURDAY LOOKS TO
BE ANOTHER WARM DAY AS MID-LEVEL RIDGING AND INCREASING H8 TEMPS
BUILD ACROSS THE UPPER GREAT LAKES. TEMPS SHOULD REACH THE 80S FOR
MOST OF THE CWA. MID-LEVEL TROUGHING GLANCING THE NORTHERN HIGH
PLAINS EARLY SATURDAY WILL RESULT IN LOW-PRESSURE DEVELOPMENT ACROSS
THE NORTHERN PLAINS AND SOUTH-CENTRAL CANADA. GUIDANCE SHOWS SOME
DIFFERENCES IN THE TIMING OF AN ASSOCIATED COLD FRONT CROSSING THE
CWA...BUT A ROUND OF SHOWERS AND STORMS SHOULD AFFECT THE AREA
SOMETIME LATE SATURDAY NIGHT THROUGH SUNDAY. EITHER WAY...GUSTY
SOUTHERLY WINDS OVER 25MPH WILL LIKELY OCCUR AHEAD OF THIS FRONT
SATURDAY INTO SUNDAY MORNING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 132 AM EDT MON AUG 17 2015
SOME -SHRA/PERHAPS A TS IN ADVANCE OF A COLD FNT APRCHG FM THE W WL
IMPACT MAINLY SAW DURING THE EARLY MRNG HRS. THE ARRIVAL OF DRIER
LLVL AIR WL ENSURE CONDITIONS REMAIN VFR AT CMX AND IWD EVEN IF SOME
-SHRA FALL THERE. BUT SAW COULD PICK UP MVFR CONDITIONS WITH MORE
HUMID LLVL AIR LINGERING. SINCE THE COLD FNT WL STALL JUST TO THE S
ON MON...AN UPPER DISTURBANCE TRACKING ALONG THIS BNDRY WL BRING A
CONTINUED CHC OF MORE -SHRA INTO THE AFTN AT SAW. WITH A WSHFT TO
AN UPSLOPE NNE DIRECTIN IN THE AFTN AND MORE LINGERING MSTR...MVFR
CIGS ARE LIKELY AT SAW FOR A TIME. SINCE CMX AND IWD WL BE FARTHER
FM THE FNT AND DEEPER INTO THE INCOMING DRY AIRMASS...VFR CONDITIONS
WL REMAIN THE RULE THERE THRU THE TAF PERIOD..
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 235 PM EDT SUN AUG 16 2015
SOUTHWEST WINDS TO 20-25 KNOTS TODAY WILL DIMINISH AND VEER NW
TONIGHT AS A COLD FRONT MOVES THROUGH. PATCHY FOG WILL CONTINUE TO
BE POSSIBLE THROUGH TONIGHT AS HUMID AIR MOVES OVER THE COOLER
WATERS OF THE GREAT LAKES. WINDS WILL STAY AT OR BELOW 20 KNOTS
THROUGH TUE NIGHT...THEN INCREASE TO UP TO 30 KNOTS ON WED INTO THU
MORNING AS THE PRESSURE GRADIENT TIGHTENS ACROSS THE AREA WITH A
STRONGER LOW PRESSURE SYSTEM MOVING THROUGH THE REGION. COULD BE
SOME NW GALE FORCE GUSTS TO 35 KNOTS THU MORNING BEHIND THIS STRONG
LOW.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...KC
MARINE...07
AREA FORECAST DISCUSSION
NWS DULUTH MN
413 AM CDT MON AUG 17 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 332 AM CDT MON AUG 17 2015
IN THE UPPER LEVELS A BROAD TROF OF LOW PRESSURE STRETCHES ACROSS
MUCH OF THE THE WRN 1/2 OF THE COUNTRY. IT`S THIS TROF AND
EMBEDDED SHORT WAVES THAT WILL BRING RAIN TO THE NORTHLAND THIS
WEEK.
BUT FIRST...CLOUDS AND MOISTURE WERE STILL STREAMING INTO THE
FAR EASTERN SECTION OF THE WI FORECAST AREA...MAINLY PRICE
COUNTY. THE LOLVL JET OF 40 KTS CONTINUED ALONG A COLD FRONT THAT
WENT THROUGH MOST OF THE AREA YESTERDAY...AND IS HELPING TO
GENERATE A FEW REMAINING SHOWERS IN THE AREA. THE FRONT SHOULD BE
MOVING OUT LATER THIS MORNING. IN THE MEANTIME...HIGH PRESSURE
BUILDING INTO THE REGION WILL BRING SUNSHINE TO MN ...AND GRADUAL
SUNSHINE TO NORTHWEST WI TODAY. DRIER AND COOLER TEMPERATURES CAN
BE EXPECTED AS DEW POINTS DROP INTO THE 40S IN MN AND THE 50S IN
WI.
LOOKING AHEAD....A SHORTWAVE WILL DIG INTO THE LONG WAVE TROF
TODAY...RESULTING IN SFC LOW PRESSURE TO FORM IN THE CENTRAL
ROCKIES. THIS LOW PRESSURE SYSTEM WILL MOVE NORTHEAST INTO THE
REGION TUESDAY. BY TUESDAY AFTERNOON THE SFC SYSTEM WILL BE
SOMEWHERE IN THE IOWA/NEBRASKA REGION...WITH A STRONG BAROCLINIC
ZONE ACROSS SRN MN/CENTRAL WI. INTENSE MOISTURE TRANSPORT ACROSS
THIS WILL PUT NRN WI AT BEST RISK FOR RAIN AND STORMS. STRONG EAST
WINDS WILL ALSO DEVELOP THE OF THE LOWS ADVANCE. AS THE LOW NEARS
SRN MN TUESDAY AFTERNOON...THE CHANCE OF RAIN WILL INCREASE NWRD.
THE MODELS ARE IN GOOD AGREEMENT WITH THE OVERALL CONCEPT OF THIS
FALL-LIKE WEATHER SYSTEM. BUT THERE ARE SOME MINOR DIFFERENCES IN
SPREAD AND EVENTUAL TRACK THAT COULD BE RECONCILED WITH TIME.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 332 AM CDT MON AUG 17 2015
A DEEP SFC LOW PRESSURE SYSTEM WILL BE LIFTING NEWD FROM THE TWIN
CITIES INTO NRN WI AND WRN LAKE SUPERIOR TUESDAY NIGHT AND WEDNESDAY
BRINGING WIDESPREAD RAIN WITH EMBEDDED THUNDERSTORMS TO THE ENTIRE
FORECAST AREA. THE DOMINANT FORCING WITH THIS SYSTEM IS EXPECTED TO
BE ON THE SYNOPTIC AND MESO-ALPHA SCALES ASSOCIATED WITH THE
DEEPENING UPPER TROUGH AND STRENGTHENING SFC LOW. MODEST WAA AHEAD
OF THE LOW WILL TIGHTEN THE THERMAL GRADIENT ALONG THE ELEVATED WARM
FRONT EXTENDING TO THE E/NE INTO CENTRAL WI AND PRODUCE A STRONG
LAYER OF MID-LEVEL F-GEN THAT WILL LIFT NWD ACROSS THE NORTHLAND AND
ENHANCE THE PRECIPITATION EFFICIENCY. A STRONG AREA OF Q-VECTOR
CONVERGENCE ALIGNED WITH STEEP MID-LEVEL LAPSE RATES WILL MOVE
ACROSS THE REGION AND AID IN THE STRENGTHENING OF THE LOW AND
SUPPLEMENT THE LARGE-SCALE LIFT TO PRODUCE HEAVY RAIN THROUGH THE
AREA. DEEP LAYER MOISTURE WILL INCREASE AS THE SYSTEM DEVELOPS WITH
PWATS FORECAST 1-1.5 INCHES. THE OTHER NOTABLE FEATURE WITH THIS
SYSTEM WILL BE THE STRONG E/NE WINDS OFF LAKE SUPERIOR. EXPECTING
SUSTAINED NE WINDS TUE NIGHT AND WED AROUND 20 TO 25 MPH AND GUSTS
30 TO 35 MPH.
THIS IMPRESSIVE LOW PRESSURE SYSTEM WILL FINALLY LIFT OUT OF THE
AREA THURSDAY MORNING...BUT NOT BEFORE LINGERING RAIN SHOWERS AND A
FEW POST-FRONTAL THUNDERSTORMS TRIGGER OFF THE CAA ON THE BACK SIDE
OF THE LOW OVER THE ARROWHEAD THUR AFTERNOON. WILL SEE CONDITIONS
BEGIN TO REALLY DRY OUT OVER THE ENTIRE REGION LATE THURSDAY AS HIGH
PRESSURE BUILDS IN FROM THE WEST. THE RIDGE FLATTENS OUT ON FRIDAY
BUT CONDITIONS SHOULD REMAIN QUIET UNTIL THE NEXT DEEP TROUGH DIGS
THROUGH THE CENTRAL CONUS THIS WEEKEND. THERE ARE STILL QUITE A FEW
DIFFERENCES IN THE TIMING AND STRENGTH OF THIS NEXT WAVE...BUT THE
GENERAL MODEL CONSENSUS IS FOR ANOTHER ROUND OF WIDESPREAD RAIN AND
SCATTERED THUNDERSTORMS SAT AND SUNDAY.
THE STRONG NE WINDS OFF LAKE SUPERIOR WILL PRODUCE MUCH COLDER
TEMPERATURES NEAR AND INLAND FROM THE LAKE ON WEDNESDAY. TEMPS ON
WED WILL ONLY REACH INTO THE UPPER 50S AND LOWER 60S. THE COLDEST
NIGHT WILL BE WED NIGHT/THUR MORNING AS THE SYSTEM EXITS TO THE NE
AND WINDS SHIFT TO THE NW. EXPECT WIDESPREAD 40S ACROSS THE
NORTHLAND THURSDAY MORNING WITH A FEW UPPER 30S NOT OUT OF THE
QUESTION. A GRADUAL WARMING TREND WILL START ON THURSDAY WITH TEMPS
BACK INTO THE 70S AND LOWER 80S BY SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 100 AM CDT MON AUG 17 2015
A COLD FRONT HAS NEARLY EXITED THE FORECAST AREA...AND WILL DO SO
EARLY IN THE FORECAST CYCLE. BEHIND THE FRONT A SUBTLE SHORTWAVE
WILL LIFT FROM EASTERN NORTH DAKOTA INTO SOUTHERN ONTARIO. THE
SHORTWAVE HAS GENERATED LIGHT SHOWERS...WHICH WILL MOVE EASTWARDS
PER THE LATEST RADAR TRENDS AND HRRR OUTPUT. KEPT KINL OUT OF
SHOWER ACTIVITY...AND ENDED PRECIPITATION BETWEEN 0730Z AND 09Z AT
THE OTHER TERMINALS. EXPECTING MVFR CONDITIONS UNTIL 14Z AT KHYR
DUE TO RECENT RAINFALL...WHICH WILL REDUCE VISBY AND KEEP CIGS AT
OR BELOW 3000 FT. OTHER TERMINALS WILL REMAIN VFR THROUGH THE
FORECAST CYCLE. WINDS WILL REMAIN LIGHT ON MONDAY AS HIGH
PRESSURE BUILDS IN ALONG THE INTERNATIONAL BORDER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 74 53 61 53 / 0 0 40 90
INL 70 43 71 50 / 0 0 0 70
BRD 74 52 70 53 / 0 0 50 90
HYR 73 51 70 56 / 10 10 50 90
ASX 74 53 70 55 / 10 10 30 90
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...CLC
LONG TERM...TENTINGER
AVIATION...WL
AREA FORECAST DISCUSSION
NWS DULUTH MN
100 AM CDT MON AUG 17 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM CDT SUN AUG 16 2015
THE COLD FRONT WAS STUCK ALONG THE NORTH SHORE THROUGH THE TWIN
PORTS TO JUST WEST OF HINCKLEY AT 19Z. SW WINDS WERE FOUND AHEAD OF
THE FRONT WITH WEST TO NW WINDS BEHIND THE FRONT. THE GUSTY WINDS
WILL SUBSIDE NEAR SUNSET. CLOUDS COVERED THE ENTIRE REGION AS WELL.
A FEW SHOWERS HAD DRIFTED OVER NORTHERN CASS COUNTY EARLIER AS
WALKER HAD REPORTED LIGHT RAIN. NOT EXPECTING ANY MORE RAIN IN NE MN
TONIGHT. THUNDERSTORMS NEAR THE TWIN CITIES ARE EXPECTED TO EXPAND
NEWD INTO NW WI LATE THIS AFTERNOON WHERE THE AXIS OF BEST
INSTABILITY WAS FOUND AT 19Z. MUCAPE RANGED FROM 1000-2000 J/KG AND
THE MUCIN WAS WEAKENING.
EXPECT THE THUNDERSTORMS TO PERCOLATE OVER NW WI TONIGHT AND MONDAY
AS THE COLD FRONT CONTINUES TO VERY SLOWLY MOVE EWD. THE FRONT
SHOULD BE EXITING THE NORTH CENTRAL WI PORTION OF THE FORECAST AREA
IN THE AFTERNOON. ELSEWHERE...HIGH PRESSURE WILL BE BUILDING INTO
THE REGION. EXPECT THE CLOUDS TO GRADUALLY DISSIPATE TONIGHT FROM NW
TO SE...WITH THE EXCEPTION OF NW WI. CLOUDS WILL REFORM WHERE THEY
HAD DIMINISHED ON MONDAY. MAX TEMPS ON MONDAY WILL BE LOWER THAN THE
LAST FEW DAYS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 306 PM CDT SUN AUG 16 2015
A RATHER ACTIVE LATE-SUMMER PATTERN APPEARS TO BE SETTING UP FOR
MUCH OF THE UPCOMING WEEK ACROSS THE NORTHERN TIER OF STATES INTO
THE WESTERN GREAT LAKES REGION.
MOST OF THE MEDIUM RANGE MODELS HAVE BEEN QUITE CONSISTENT IN A
STRONGLY AMPLIFYING WAVE AND DEEP-LAYER CYCLOGENESIS ACROSS THE
IOWA/MINNESOTA/WISCONSIN AREA FROM TUE NIGHT INTO WED NIGHT..AND THE
LATEST RUNS CONTINUE THIS GENERAL TREND. CONFIDENCE THUS CONTINUES
TO INCREASE THAT WE WILL LIKELY HAVE A WIDESPREAD RAIN EVENT DURING
THIS TIME PERIOD..WITH PROBABLY SOME EMBEDDED THUNDERSTORMS. THE
DEGREE OF COVERAGE OF TSTORMS..AND POTENTIAL FOR SEVERE IS STILL
HIGHLY IN QUESTION HOWEVER..DUE TO DIFFERENCES IN THE VARIOUS MODELS
HANDLING OF THE INSTABILITY FIELDS AND PATH OF THE SURFACE LOW.
REGARDLESS OF THE DETAILS..WITH SUCH A STRONGLY DEEPENING SYSTEM SO
DEEP INTO THE WARM SEASON..THIS WILL NEED TO BE MONITORED CLOSELY.
IT APPEARS THAT POTENTIAL FOR WIDESPREAD BENEFICIAL RAINS IS RATHER
HIGH.
AFTER THIS SYSTEM DEPARTS..THE THUR-FRI TIME PERIOD LOOKS TO BE
SOMEWHAT BENIGN WITH HIGH PRESSURE BRIEFLY BUILDING IN.
HOWEVER..WARM/MOIST ADVECTION IS EXPECTED TO INCREASE AGAIN FRI-SAT
TIME FRAME AS NEXT WAVE APPROACHES. WHILE IT IS STILL A LONG WAY
OFF..THE CURRENT MODEL RUNS ARE HINTING THAT A SIMILAR STRONGLY
AMPLIFYING SCENARIO COULD PLAY OUT NEXT WEEKEND..BUT PERHAPS A BIT
FARTHER TO THE WEST. NATURALLY..CONFIDENCE ON ANY DETAILS ARE LOW
THIS FAR OUT..BUT AT LEAST SOME POTENTIAL SEEMS TO EXIST FOR
SIGNIFICANT SEVERE WEATHER AND/OR HEAVY RAINFALL IF THE FARTHER WEST
SOLUTION VERIFIES AND THE INSTABILITY AND HIGH PW AXIS CAN BUILD
NORTHWARD INTO NRN MN.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 100 AM CDT MON AUG 17 2015
A COLD FRONT HAS NEARLY EXITED THE FORECAST AREA...AND WILL DO SO
EARLY IN THE FORECAST CYCLE. BEHIND THE FRONT A SUBTLE SHORTWAVE
WILL LIFT FROM EASTERN NORTH DAKOTA INTO SOUTHERN ONTARIO. THE
SHORTWAVE HAS GENERATED LIGHT SHOWERS...WHICH WILL MOVE EASTWARDS
PER THE LATEST RADAR TRENDS AND HRRR OUTPUT. KEPT KINL OUT OF
SHOWER ACTIVITY...AND ENDED PRECIPITATION BETWEEN 0730Z AND 09Z AT
THE OTHER TERMINALS. EXPECTING MVFR CONDITIONS UNTIL 14Z AT KHYR
DUE TO RECENT RAINFALL...WHICH WILL REDUCE VISBY AND KEEP CIGS AT
OR BELOW 3000 FT. OTHER TERMINALS WILL REMAIN VFR THROUGH THE
FORECAST CYCLE. WINDS WILL REMAIN LIGHT ON MONDAY AS HIGH
PRESSURE BUILDS IN ALONG THE INTERNATIONAL BORDER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 53 61 55 62 / 0 40 80 60
INL 43 71 52 67 / 0 0 40 30
BRD 52 70 53 65 / 0 50 70 40
HYR 51 70 55 63 / 10 50 80 70
ASX 53 70 56 67 / 10 30 80 70
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
LS...NONE.
&&
$$
SHORT TERM...GSF
LONG TERM...MILLER
AVIATION...WL
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
1135 PM MDT SUN AUG 16 2015
.AVIATION...
06Z TAF CYCLE
THUNDERSTORM ACTIVITY HAS LARGELY DIMINISHED...HOWEVER A FEW
STRAY STORMS ARE CURRENTLY WORKING INTO THE EAST CENTRAL PLAINS OF
NEW MEXICO WITH ONLY SHOWERS STRUGGLING TO HOLD FARTHER NORTHEAST
AT THE MOMENT. GUSTY DOWNBURST WINDS...SMALL HAIL...AND HEAVY
DOWNPOURS WILL ACCOMPANY THUNDERSTORMS WITH NEW DEVELOPMENTEXPECTED
POSSIBLE INTO THE NORTHEAST PLAINS OVERNIGHT. THE BULK OF THE
ACTIVITY WILL LIKELY DIMINISH BEFORE 17/1000UTC...BUT A FEW CELLS
COULD SUSTAIN THEREAFTER. STORMS ON MONDAY WILL STRETCH FROM THE
SOUTH CENTRAL PARTS OF NEW MEXICO TO THE NORTHEAST CORNER WITH A
FEW STORMS BECOMING SEVERE IN THE NORTHEAST LATE IN THE AFTERNOON.
52
&&
.PREV DISCUSSION...306 PM MDT SUN AUG 16 2015...
.SYNOPSIS...
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS EXPECTED FOR THE
EASTERN PLAINS TONIGHT AS STORMS THIS AFTERNOON ROLL OFF THE
CENTRAL MOUNTAIN CHAIN. ON MONDAY AND TUESDAY...A BETTER CHANCE OF
SEVERE WEATHER EXISTS ACROSS NORTHEAST NEW MEXICO WHERE LARGE HAIL
AND DAMAGING WINDS WILL BE POSSIBLE. MEANWHILE...DRIER CONDITIONS
WILL PREVAIL ACROSS THE WEST. A COLD FRONT THAT RACES THROUGH THE
PLAINS TUESDAY WILL BE RESPONSIBLE FOR MUCH COOLER TEMPERATURES
ACROSS THE EAST ON WEDNESDAY...WITH MANY LOCALES STRUGGLING TO
REACH 80. DRIER WEATHER IS IN STORE AREA WIDE FOR WEDNESDAY AND
THURSDAY.
&&
.DISCUSSION...
CONVECTION IS NOT QUITE AS ROBUST TODAY AS IT WAS YDAY AT THIS
TIME. THIS MAY BE OWING TO A COOLER START DUE TO REMNANT CLOUD
COVER THIS MORNING...AND PERHAPS MORESO...THERE IS SOME EVIDENCE
ON WV SATELLITE OF DRIER AIR MOVING IN FROM THE WEST. REMNANT
MOISTURE PLUME LOOKS TO BE STRETCHING ACROSS THE EAST...AND
ALONG/EAST OF THE CENTRAL MTN CHAIN WILL BE THE FAVORED AREA FOR
STORMS THROUGH TONIGHT. SIMILAR TO YESTERDAY...THE HRRR SHOWS A
CLUSTER OF STORMS ACROSS THE PLAINS LATE THIS EVENING. A FEW
STORMS MAY BE STRONG OR SEVERE...OR MAY CREATE LOCALIZED FLOODING
ISSUES. HAVE INCREASED POPS ACCORDINGLY ONCE AGAIN.
MONDAY LOOKS TO BE A BIT MORE FAVORED FOR SEVERE WX ACROSS THE
NORTHEAST AS THE NOSE OF AN UPPER LEVEL JET PUSHES INTO COLORADO
AND NORTHERN NM...INCREASING SHEAR. SHOULD STILL BE PLENTY OF LOW
LEVEL MOISTURE AROUND...AND CAPE VALUES SHOULD BE SIMILAR TO THIS
AFTN...BETWEEN 1000-1500 J/KG. THUS...THE ADDED SHEAR WILL BE THE
MAIN FACTOR INCREASING SEVERE CHANCES. LARGE HAIL AND DAMAGING
WIND GUSTS WILL BE THE MAIN THREATS. FURTHER SOUTH ACROSS THE
PLAINS...STORM COVERAGE WILL BE MUCH LESS...BUT COULD STILL SEE A
STRONG STORM OR TWO DEVELOP.
THE UPPER LEVEL TROUGH THAT WE HAVE BEEN ADVERTISING WILL CROSS
THE CENTRAL ROCKIES MONDAY NIGHT AND EARLY TUESDAY...WITH AN
ASSOCIATED PACIFIC FRONT SLIDING FROM NW TO SE ACROSS NM. FOR A
CHANGE..IT WILL ACTUALLY BE BREEZY TO WINDY ACROSS MUCH OF NW NM.
STRUGGLED WITH WHAT TO DO WITH HIGH TEMPS ACROSS THE CENTRAL AND
WEST. THE DRIER AIR WOULD SUGGEST WARMER...BUT LOWER
HEIGHTS/COOLER 700MB TEMPS WOULD SUGGEST COOLER. LATER ON TUESDAY
MORNING THRU TUESDAY AFTN...THE MORE SUBSTANTIAL BACK DOOR FRONT
WILL SLIDE DOWN THE PLAINS AND MODELS ARE NOW ADVERTISING IT WILL
PUSH THRU THE GAPS OF THE CENTRAL MTN CHAIN TUESDAY NIGHT. LOW
LEVEL MOISTURE WILL BE REPLENISHED BEHIND THE BACK DOOR
FRONT...AFTER IT WAS SCOURED OUT BY THE PACIFIC FRONT. UPSLOPE
FLOW AND CONTINUED INSTABILITY SHOULD YIELD SCATTERED STORMS
ACROSS AT LEAST THE NE. ONCE AGAIN...A FEW STORMS MAY BE STRONG OR
SEVERE.
AFTER THE TROUGH PASSAGE...MUCH DRIER MID LEVEL AIR WILL BE IN
PLACE ACROSS THE LAND OF ENCHANTMENT...SIGNIFICANTLY LIMITING
PRECIP CHANCES FOR WEDNESDAY. ANY STORM WILL BE HARD TO COME
BY...DESPITE THE LOW LEVEL MOISTURE NOT ENTIRELY MIXING OUT ACROSS
THE PLAINS. ADDITIONALLY...IT WILL BE SIGNIFICANTLY COOLER ACROSS
THE EAST ON WEDNESDAY BEHIND THE FRONT WITH MANY AREAS STRUGGLING
TO REACH 80F. THE DRY WX WILL CONTINUE ON THURSDAY...THEN MODELS
CONTINUE TO STRUGGLE WITH THE UPPER AIR PATTERN. THE EC SHOWS
ANOTHER STRONG TROUGH ACROSS THE CENTRAL ROCKIES ON
SATURDAY...WITH DRIER AIR CONTINUING TO FILTER INTO NM. THE GFS
HAS THIS TROUGH MUCH FURTHER NORTH WITH THE UPPER HIGH TRYING TO
REBUILD OVER THE SW CONUS...PERHAPS ALLOWING FOR SOME MOISTURE
SEEPAGE. BEHIND THIS AFOREMENTIONED TROUGH...ANOTHER BACK DOOR
FRONT SHOULD REPLENISH LOW LEVEL MOISTURE ACROSS THE PLAINS SAT
NIGHT/SUN. BUT WITHOUT A S OR SWLY FLOW ALOFT...THINK THE GFS IS
OVERDOING THE MOISTURE FLUX/QPF IN THE EXTENDED...AT LEAST THURS
NIGHT-SAT. STAY TUNED.
34
&&
.FIRE WEATHER...
UPPER HIGH CENTER HAS DRIFTED FARTHER WEST INTO ARIZONA AND
CIRCULATION ATTEMPTING TO PUSH SOME DRIER MID LEVEL AIR INTO THE
FOUR CORNERS REGION. THE DRYING TREND OVER WESTERN AND CENTRAL NM
BECOMES MORE PRONOUNCED BY MID TO LATE WEEK AS A DISTURBANCE SWEEPS
OUT OF THE NORTHERN ROCKIES AND NORTHWEST FLOW PREDOMINATES OVER NM.
VERY SPOTTY CRITICAL CONDITIONS POSSIBLE FROM THE NORTHWEST PLATEAU
TO THE CENTRAL HIGHLANDS TUESDAY AFTERNOON.
A SURFACE FRONT TUESDAY NIGHT WILL PUSH HIGHER DEW POINTS INTO THE
RGV BUT THEY SHOULD MIX OUT WEDNESDAY. ANOTHER FRONT LATE IN THE
WEEK OR OVER THE WEEKEND COULD REPLENISH LOW LEVEL MOISTURE CENTRAL
AND EAST...BUT BY THEN...A SPRAWLING RIDGE ALOFT COULD STEER THE
MAJORITY OF MONSOON MOISTURE AWAY FROM NM.
CONVECTION ALREADY GOING BY MIDDAY OVER THE NORTHERN AND WESTERN
HIGH TERRAIN. CELL MOTION TO THE SOUTH AND SOUTHWEST...WITH SHORT
TERM MODELS INDICATING THE EASTERN PLAINS WILL SEE RAIN THIS EVENING
AND OVERNIGHT...AFTER STORMS GET GOING OVER SE CO. POTENTIAL FOR
ISOLD STRONG TO SEVERE STORMS NE. ALSO LOOKING FOR A CONVECTIVELY
DRIVEN EAST WIND INTO THE RGV TONIGHT. MONDAY INTO TUESDAY WILL SEE
POTENTIAL FOR ISOLATED STRONG TO SEVERE STORMS FROM THE CENTRAL MT
CHAIN EASTWARD. THE BATTLE OF THE DRY IN THE WEST AND THE WET IN THE
EAST BECOMES SHARPER TUESDAY...WITH ONLY ISOLATED CONVECTION
FORECAST WEST. HIGH HAINES FORECAST TO BE WIDESPREAD OVER THE
CENTRAL AND WEST TUESDAY...AND OVER NEARLY ALL OF THE FORECAST AREA
THURSDAY AND FRIDAY. OVERALL...OVERNIGHT RH TRENDS WILL BE LESS
GENEROUS WEST AND CENTRAL AS THE WORK WEEK PROGRESSES...AND AFTERNOON
MIN RH VALUES WILL DECREASE AS WELL. HIGHS WILL GENERALLY BE NEAR TO
ABOVE AVERAGE...EXCEPT IN THE EAST WEDNESDAY IN THE WAKE OF
TUESDAY/S FRONT.
CONVECTION TAPERS OFF WEDNESDAY/THURSDAY WITH A FEW MOSTLY DIURNAL
STORMS OVER THE HIGHER TERRAIN...BUT SLOWLY INCREASES IN AREAL
COVERAGE INTO THE WEEKEND.
ECMWF A LITTLE SLOWER THAN GFS DEVELOPING THE MASSIVE RIDGE ALOFT
EARLY NEXT WEEK...BY 240 HRS IT HAS A MUCH STRONGER TROF OVER THE
NRN ROCKIES AND POSSIBLY A BETTER FETCH OF MOISTURE INTO NM FROM OLD
MEXICO. SO INCREASING UNCERTAINTY IN THE FORECAST WITH TIME.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1215 AM CDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1213 AM CDT MON AUG 17 2015
JUST A MINOR UPDATE TO LOW TEMPERATURES BY A FEW DEGREES. CURRENT
OBSERVATION TRENDS WOULD INDICATE WIDESPREAD READINGS IN THE MID
40S ARE LIKELY TONIGHT.
UPDATE ISSUED AT 953 PM CDT SUN AUG 16 2015
BLENDED IN CURRENT CONDITIONS TO THE FORECAST WITH ONLY ISOLATED
SHOWERS LEFT IN THE SOUTHERN JAMES RIVER VALLEY. AFTER
COLLABORATION WITH SURROUNDING OFFICES...OPTED TO REMOVE THE
OVERNIGHT POP IN SOUTHWEST NORTH DAKOTA. THE LATEST NAM KEEPS IT
DRY IN THAT REGION OVERNIGHT...AND THAT LINES UP WITH HRRR AND RAP
13 TOO. ONE AREA TO MONITOR OVERNIGHT FOR A POTENTIAL SHOWER IS
THE NORTH CENTRAL WHERE THE RAP 13 AND HRRR BOTH HINT AT THE
POSSIBILITY LATE TONIGHT / EARLY MONDAY MORNING.
UPDATE ISSUED AT 902 PM CDT SUN AUG 16 2015
MADE ANOTHER QUICK UPDATE AS THE SHOWERS CONTINUE THEIR TREK
EASTWARD. DECIDED TO REMOVE THE MENTION OF THUNDER WITH ONLY
LIMITED INSTABILITY AVAILABLE.
UPDATE ISSUED AT 654 PM CDT SUN AUG 16 2015
MAIN CHANGE WAS TO HOLD ONTO SHOWERS / ISOLATED THUNDERSTORMS A
COUPLE MORE HOURS THIS EVENING. THE SHORT TERM MODELS HAVE
STRUGGLED TO HANDLE THE ONGOING PRECIPITATION. IT APPEARS MUCH OF
THE ACTIVITY IS IN ASSOCIATION WITH THE RIGHT REAR QUADRANT OF AN
UPPER LEVEL JET STREAK. THIS FEATURE IS FORECAST TO WEAKEN THIS
EVENING AS IT MOVE SOUTH AND EAST. WILL STILL TREND TO A DRY
FORECAST LATER THIS EVENING. HAVE ALSO INCREASED SKY COVER THIS
EVENING IN ASSOCIATION WITH THE PRECIPITATION.
UPDATE ISSUED AT 521 PM CDT SUN AUG 16 2015
QUICK UPDATE TO SPREAD THE ISOLATED SHOWERS / THUNDERSTORMS A ROW
OF COUNTIES FARTHER EAST. WE ALSO BLENDED IN CURRENT CONDITIONS...
OTHERWISE THE FORECAST IS ON TRACK.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 306 PM CDT SUN AUG 16 2015
CURRENT SURFACE ANALYSIS PLACES LOW OVER NORTHERN ONTARIO WITH
COLD FRONT DROPPING THROUGH THE UPPER MIDWEST INTO THE CENTRAL
PLAINS. COOL HIGH PRESSURE CONTINUES TO SLIDE OVER THE NORTHERN
ROCKIES INTO THE NORTHERN PLAINS BRINGING REFRESHING TEMPERATURES
AFTER A HOT DAY YESTERDAY. UPPER LEVEL ANALYSIS BRING CYCLONIC
WEST/SOUTHWESTERLY FLOW TO THE AREA WITH A VARIETY OF WEAK SHORT
WAVES NOTED AND UPPER JET STREAK PASSING THROUGH. THIS CONTINUES
TO BRING SOME WEAK SHOWERS/THUNDERSTORMS TO SOUTHERN/WESTERN
PORTIONS OF THE AREA.
FOR THE REST OF THIS AFTERNOON INTO TONIGHT...SHOWERS/WEAK STORMS
OVER THE SOUTHERN JAMES RIVER VALLEY WILL CONTINUE TO PUSH OFF TO
THE EAST...WHILE PRECIPITATION OVER THE WESTERN PORTIONS OF THE
STATE AFFILIATED WITH PASSING JET STREAK MAY LINGER INTO THE
EARLY EVENING BEFORE DISSIPATING. WITH LIMITED INSTABILITY TO DEAL
WITH...STORMS SHOULD REMAIN WEAK. A COOL NIGHT IS EXPECTED AS
SURFACE HIGH SETTLES OVER THE REGION.
ON MONDAY...BROAD CYCLONIC FLOW REMAINS OVER THE REGION WITH
PRECIPITATION CHANCES INCREASING PRIMARILY OVER SOUTHWESTERN AREAS
THROUGH MID-DAY BEFORE SPREADING TOWARDS THE NORTHEAST LATER IN
THE DAY. WILL MENTION MAINLY SHOWERS BUT STILL KEEP LOW THUNDER
CHANCES IN THE FORECAST WITH MINIMAL INSTABILITY NOTED.
TEMPERATURES WILL REMAIN BELOW AVERAGE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 354 PM CDT SUN AUG 16 2015
THE FORECAST FOCUS IS ON THE POTENTIAL FOR TWO RAIN EVENTS THIS
WEEK.
MODELS AND ENSEMBLES AGREE THAT BROAD SCALE CYCLONIC FLOW ACROSS THE
NORTHERN TIER WILL DIRECT TWO MIDDLE LEVEL ALASKA SHORTWAVES INTO
THE DAKOTAS AND SOUTHERN CANADA THIS WEEK. LARGE SCALE ASCENT
ASSOCIATED WITH THE FIRST WILL SPREAD ACROSS NORTH DAKOTA BEGINNING
ON MONDAY NIGHT...AND WILL SUPPORT PRECIPITATION THROUGH TUESDAY
EVENING...PER THE 06 UTC GEFS AND 12 UTC GFS/ECMWF/GEM GLOBAL.
CONVECTIVE INSTABILITY IS LIMITED IN GUIDANCE...SO GRIDDED FORECASTS
INDICATE ONLY A SLIGHT CHANCE FOR THUNDERSTORMS DESPITE LIKELY
SHOWERS.
THERE IS GREATER UNCERTAINTY WITH STRENGTH OF THE SECOND
SYSTEM...THOUGH THERE IS GOOD AGREEMENT THAT H5 HEIGHT FALLS WILL
SPREAD INTO WESTERN NORTH DAKOTA ON FRIDAY...WITH ASSOCIATED
THUNDERSTORM ACTIVITY LASTING INTO SUNDAY. THE 12 UTC ECMWF IS ON
THE AMPLIFIED SIDE OF THE 06 UTC GEFS ENSEMBLE SPREAD...AND THE 12
UTC GFS IS IN THE MIDDLE. SINCE THE SHORTWAVE WILL NOT CROSS THE
BERING STRAIT UNTIL WEDNESDAY...THE ENVELOPE OF SOLUTIONS WILL
PROBABLY HAVE LARGE SPREAD UNTIL MIDWEEK.
THE AFOREMENTIONED BROAD CYCLONIC FLOW WILL SUPPORT TEMPERATURES
NEAR OR BELOW NORMAL ACROSS THE NORTHERN HIGH PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1213 AM CDT MON AUG 17 2015
VFR CONDITIONS AT ALL TAF SITES THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...AJ
SHORT TERM...JJS
LONG TERM...SCHECK
AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
351 AM EDT MON AUG 17 2015
.SYNOPSIS...
MOISTURE INCREASES MONDAY THROUGH WEDNESDAY. COLD FRONT THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
WATER VAPOR IMAGERY SHOWING THE DRAW OF DEEPER MOISTURE INTO THE
CWA IN RESPONSE TO AN UPPER LEVEL LOW PRESSURE SYSTEM LOCATED OVER
THE CONFLUENCE OF THE OHIO AND MISSISSIPPI RIVERS. NAM CONTINUES TO
MAINTAIN AN AGGRESSIVE NATURE WITH THE RESULTANT CONVECTIVE CHANCES
TODAY WHILE THE HRRR AND RAP ARE FAR LESS SO. FEEL MORE COMFORTABLE
WITH THESE TAMER MODELS...AND WILL BE INTERESTED TO SEE THEIR
SOLUTIONS FOR THE ACTIVITY TONIGHT. PUTTING A LOT OF STOCK INTO THE
UPPER LEVEL LOW MOVING THROUGH THE AREA WITH LIKELY POPS...AGAIN
MUCH MORE AGGRESSIVE IN THE NAM SOLUTION.
MAV HAS BEEN THE HOT GUIDANCE OF CHOICE LATELY...SO LEAN ON THIS
HEAVILY FOR THE AFTERNOON HIGHS TODAY. LIKE HOW IT KEEPS SOME OF THE
SOUTHERN ZONES SLIGHTLY COOLER THAN THE NORTH GIVEN THE ARRIVAL OF
CLOUDS EARLIER IN THE DAY AND THE BETTER CHANCES FOR CONVECTION.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS SHOW A SERIES OF UPPER DISTURBANCES MOVING THROUGH A DEEPER
MOIST SOUTHWEST FLOW TUESDAY AND WEDNESDAY...BEFORE A COLD FRONT
MOVES THROUGH ON THURSDAY TO BRING IN DRIER AND COOLER AIR FOR THE
REMAINDER OF THE WORK WEEK. MODELS HINT AT ONE DISTURBANCE MOVING
ACROSS EARLIER ON TUESDAY...ANOTHER ONE TUESDAY NIGHT AND EARLY
WEDNESDAY...BEFORE THE COLD FRONT MOVES ACROSS ON THURSDAY. DESPITE
THE LACK OF A LOW LEVEL FOCUS BEFORE THE COLD FRONT...THE
DISTURBANCES COMBINING WITH PW`S AOA 1.5 INCHES SUGGESTS HIGH POPS
FOR SHOWERS AND THUNDERSTORMS. WILL...FOCUS HIGHER POPS ON THE TWO
AFOREMENTIONED DISTURBANCES...BUT OTHERWISE KEEP LOWER POPS IN THE
JUICY AIR IN PLACE. SUNSHINE SHOULD BE LIMITED AND SO HIGH TEMPS
WILL BE IN THE 80S. SHOWERS AN STORMS RAMP UP AGAIN WEDNESDAY NIGHT
AND EARLY THURSDAY ALONG AND AHEAD OF THE COLD FRONT...DECREASING
FROM NORTHWEST TO SOUTHEAST DURING THURSDAY AS DRIER AND SOMEWHAT
COOLER AIR MOVES IN. HIGH PRESSURE WILL SETTLE IN FOR THURSDAY NIGHT
AND FRIDAY...WITH MOSTLY DRY WEATHER AND HIGH TEMPS AROUND 80
DEGREES FRIDAY...BUT WILL LEAVE JUST A LOW POP IN THE SOUTH AS
MODELS INDICATE SOME LINGERING MOISTURE DOWN THERE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
A COLD FRONT PASSES ON THURSDAY. THERE IS STILL NOT GREAT MODEL
CONSENSUS...WITH THE EURO GIVING THE STRONGEST SOLUTION. FOR THE
MOST PART THE MAJOR DYNAMICS WILL BE NORTH OF THE FORECAST AREA.
HAVE INCREASED POPS WITH THE FRONT FROM WHAT WAS IN THE PREVIOUS
GRIDS. HAVE EVEN INCLUDED LIKELY OVER THE MOUNTAINS. NOT SURE HOW
QUICKLY IT WILL DRY OUT AS THE FRONT MIGHT GET HUNG UP. AT THIS
TIME WENT WITH THE PREVIOUS SCENARIO AND DRIED POPS OUT STARTING
FRIDAY.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
KEEPING WITH THE TREND OF LATE VALLEY FOG THIS MORNING LIFTING
AFTER 11-12Z.
CONVECTION SPREADING INTO THE MOUNTAINS AND SOUTHWEST TO NORTHEAST
THROUGH THE LOWLANDS TODAY AS MOISTURE INCREASES. OPTED FOR
OPTIMISTIC TAFS KEEPING THE CONVECTION OUT AND USING VCSH WHEN
POSSIBLE AS OPPOSED TO VCTS. MAY NEED TO BRING IN MORE VCTS/TSRA
FOR THE NEXT ROUTINE ISSUANCE AT 12Z THIS MORNING.
CONVECTION WILL NOT NECESSARILY WANE WITH THE LOSS OF HEATING THIS
EVENING. A SHORT WAVE TROUGH AXIS ALOFT WILL KEEP THE CHANCES FOR
SHOWERS AND STORMS GOING INTO THE OVERNIGHT TIME PERIOD.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
ALTERNATE SCENARIOS: TIMING OF RIVER VALLEY FOG COULD VARY. MAY
NEED MORE VCTS/TSRA TODAY.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 08/17/15
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
CRW CONSISTENCY H H M L L L M H H H H H
HTS CONSISTENCY H H M L L L M H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H L L L L L L H H H H H
PKB CONSISTENCY H H M L L L M H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
IFR CONDITIONS POSSIBLE IN AREAS OF SHOWERS AND THUNDERSTORMS WITH
THE COLD FRONT ON THURSDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...FB
AVIATION...26
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1156 PM CDT SUN AUG 16 2015
.AVIATION UPDATE...
FOR 06Z AVIATION.
MODELS HAVE INCREASED THEIR TREND WITH FOG ACROSS THE AREA THIS
EVENING...ESPECIALLY FOR KCKV AND KCSV. KCSV IS ALREADY SEEING VIS
DROPPING TO AROUND 7 MILES THIS EVENING. HAVE MVFR AND EVEN IFR
FOG IN FOR KCSV...AND MVFR FOR KCKV BEFORE SUNRISE. WOULD NOT BE
SURPRISED TO SEE SIMILAR CONDITIONS AS LAST NIGHT...WITH SOME LIFR
FOG POSSIBLE AS WELL. KBNA MAY SEE SOME FOG...BUT KEPT IN VFR FOR
NOW. RAIN CHANCES SHOULD INCREASE AFTER 12Z THIS MORNING FOR ALL
TERMINALS...WITH PRECIP CHANCES CONTINUING INTO THE AFTERNOON.
KCSV HAS A BETTER CHANCE FOR PRECIP DURING THE DAY TOMORROW
COMPARED TO THE OTHER TERMINALS...BUT PRECIP CHANCES WILL REMAIN
IN THE FORECAST FOR THE DURATION OF THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 847 PM CDT SUN AUG 16 2015/
EVENING UPDATE...
CONVECTION HAS SINCE WANED ACROSS MIDDLE TN AND WEAKENED FURTHER
SOUTH ACROSS ALABAMA. THE UPPER LOW OVERHEAD WILL RETROGRADE A
LITTLE TO THE NORTHWEST THROUGH TOMORROW...SO MOISTURE SHOULD
STILL DRAW NORTHWARD OVERNIGHT. WILL INCREASE SLIGHT-LOW CHC POPS
THROUGH DAWN FROM THE SOUTH TO THE NORTH. THE LATEST HRRR AND NAM
GENERATE QUITE A BIT OF PRECIP AROUND 12Z SO WILL TREND THAT WAY.
WILL INCLUDE LIGHT FOG OVER NNERN AREAS AS WELL.
TEMPS LOOK ON TRACK FOR THE MOST PART. TRENDED A TAD WARMER WITH
CLOUDS INCREASING FROM THE SOUTH THOUGH.
NO OTHER CHANGES MADE. UPDATE OUT SHORTLY.
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
06
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
349 AM CDT MON AUG 17 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
THE COLD FRONT EXTENDED FROM NORTH CENTRAL WISCONSIN INTO
NORTHERN KANSAS EARLY THIS MORNING. REGIONAL RADARS INDICATE THE
REMAINING SHOWERS HAVE BECOME ORIENTED ALONG AND JUST BEHIND THE
FRONT WITH THE LARGEST CONCENTRATION MOVING SLOWLY NORTHEAST OUT
OF NORTHERN IOWA. THIS AREA OF SHOWERS IS ASSOCIATED WITH A WEAK
SECONDARY MOISTURE TRANSPORT AXIS THAT THE 17.06Z RAP MOVES
NORTHEAST INTO THE AREA AND THEN STARTS TO WEAKEN IT AROUND 12Z
INTO THE REST OF THE MORNING. THE 17.06Z HRRR SHOWS THESE TRENDS
WELL AND BRINGS IN THE BAND OF RAIN THROUGH ABOUT 12Z AND THEN
SHOWS IT WEAKENING AS THE MORNING PROGRESSES WITH THE WEAKENING
MOISTURE TRANSPORT.
THE FRONT WILL CONTINUE TO WORK SLOWLY SOUTH THROUGH THE REST OF
THE DAY BUT SOME UNCERTAINTY ON JUST HOW MUCH ACTIVITY WILL OCCUR
WITH IT. MOST OF THE HI-RES MESO MODELS SHOW A CONTINUED
DIMINISHING TREND INTO THE EARLY AFTERNOON WITH MAINLY SCATTERED
COVERAGE. WITH NO SHORT WAVE TROUGHS TO PROVIDE ANY DYNAMIC
SUPPORT TODAY...ANY INCREASE IN ACTIVITY WILL HAVE TO BE
THERMODYNAMICALLY DRIVEN. WITH SOME HEATING OCCURRING UNDER THE
CLOUD COVER...THE 17.00Z NAM SUGGESTS THE MU CAPE COULD INCREASE
INTO THE 1000-1500 J/KG RANGE ACROSS THE SOUTH DURING THE
AFTERNOON. THE FRONTOGENESIS IN THE 1000-850 MB LAYER ALSO SHOWS A
DIURNAL INCREASE DURING THE AFTERNOON AND THIS MAY BE ENOUGH TO
MAINTAIN SOME SCATTERED ACTIVITY ALONG THE FRONT.
DIFFERENCES AMONG THE MODELS THEN START TO SHOW UP IN HOW FAR
SOUTH THE FRONT PROGRESSES TONIGHT. THE NAM AND THE MESO MODELS
SUGGEST A GENERAL LULL IN THE ACTIVITY THIS EVENING BUT THEN START
TO BRING THE FRONT BACK LATE TONIGHT AHEAD OF THE NEXT SYSTEM.
WATER VAPOR SATELLITE THIS MORNING SHOWS THIS NEXT SHORT WAVE
TROUGH WAS OVER EASTERN WASHINGTON AND OREGON. THE GENERAL TREND
IN THE MODELS WITH THIS SYSTEM REMAINS THE SAME WITH IT
INTENSIFYING AS IT APPROACHES...FORMING A CLOSED UPPER LEVEL LOW
OVER THE EASTERN DAKOTAS TUESDAY. SOME DIFFERENCES ON HOW STRONG
THE WAVE BECOMES WITH THE 17.00Z GFS CONTINUING ITS TREND OF BEING
THE STRONGEST WITH IT AND ALSO THEN THE SLOWEST TO MOVE IT OUT.
THE UPPER LEVEL LOW AND SHORT WAVE TROUGH SHOULD THEN LIFT
NORTHEAST ACROSS MINNESOTA AND INTO CANADA TUESDAY NIGHT INTO
WEDNESDAY. THE FORCING AHEAD OF THIS WAVE WILL START TO INCREASE
LATE TONIGHT AS HEIGHT FALLS START TO SPREAD OVER THE REGION. THE
FORCING LOOKS TO BE THE STRONGEST TUESDAY NIGHT AS MODERATE PV
ADVECTION IN THE 500-300 MB LAYER MOVES ACROSS WITH THE SHORT WAVE
TROUGH. THE BEST MOISTURE TRANSPORT SHOULD STAY TO THE WEST OF THE
AREA TONIGHT BUT THERE IS SOME SUGGESTION OF A WEAK BRANCH COMING
INTO THE FRONT FOR LATE TONIGHT. THIS MOISTURE TRANSPORT THEN
CONTINUES TO INCREASE THROUGH THE DAY TUESDAY AND LOOKS TO BE
RIGHT INTO THE AREA FOR TUESDAY EVENING. BASED ON THESE SIGNALS
PLAN TO START INCREASING THE RAIN CHANCES LATE TONIGHT ACROSS THE
SOUTH WITH THE CHANCES THEN INCREASING ACROSS THE ENTIRE AREA
TUESDAY. THE HIGHEST RAIN CHANCES SHOULD OCCUR TUESDAY EVENING AS
THE FRONT MOVES BACK INTO THE AREA AS A SURFACE LOW TRACKS FROM
IOWA INTO MINNESOTA. THEN EXPECTING THE DRY SLOT TO START WORKING
IN FROM THE SOUTH FOR LATE TUESDAY NIGHT INTO WEDNESDAY AS THE
ENTIRE SYSTEM LIFTS OFF TO THE NORTH.
QUESTIONS ON JUST HOW MUCH OF A SEVERE THREAT THERE WILL BE WITH
THIS SYSTEM. EXPECTING RAIN TO BE FALLING AHEAD OF THE WARM FRONT
AND THE WARM SECTOR ITSELF TO NOT BE VERY CLEAN. THIS SHOULD LIMIT
THE AMOUNT OF INSTABILITY WITH BOTH THE NAM AND GFS SHOWING LESS
THEN 750 J/KG OF ML CAPE AVAILABLE IN THE WARM SECTOR. WITH THE
GFS BEING THE STRONGEST WITH THE SYSTEM IT PRODUCES THE MOST SHEAR
WITH 30 TO 35 KNOTS IN THE 0-3KM LAYER WHILE THE NAM STRUGGLES TO
GET 20 KNOTS IN HERE IN THE SAME LAYER. COULD SEE SOME STRONGER
STORMS DEVELOP BUT STILL NOT THINKING THERE WOULD BE MUCH IN THE
WAY OF AN ORGANZID SEVERE EVENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
ANY LINGERING RAIN CHANCES FROM THIS SYSTEM SHOULD MAINLY BE
LIMITED TO THE INTERSTATE 94 CORRIDOR FOR WEDNESDAY NIGHT BEFORE
DRY WEATHER SETTLES IN FOR THURSDAY THROUGH FRIDAY. THE RAIN
CHANCES THEN LOOK LIKE THEY WILL RETURN FOR THE UPCOMING WEEKEND.
PRETTY GOOD AGREEMENT BETWEEN THE GFS AND 17.00Z ECMWF OF A COLD
FRONT SWEEPING ACROSS THE REGION SATURDAY AND SATURDAY NIGHT. THE
SHORT WAVE TROUGH WITH THIS SYSTEM LOOKS TO BE PRETTY SIMILAR TO
THE UPCOMING SYSTEM FOR TUESDAY. IT SHOULD COME IN OFF THE
NORTHERN PACIFIC AND INTENSIFY ONCE IT CROSSES THE NORTHERN
ROCKIES BUT IT MAY TRACK SLIGHTLY FARTHER TO THE NORTH ACROSS
NORTH DAKOTA OR EXTREME SOUTHERN CANADA. THIS COULD BRING IN A
DECENT ROUND OF SHOWERS AND STORMS AGAIN AS THE FRONT COMES
ACROSS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1145 PM CDT SUN AUG 16 2015
FIRST LINE OF SHOWERS AND THUNDERSTORMS FROM EARLIER THIS EVENING
HAS WEAKENED AND STALLED OUT ACROSS SOUTHEAST MN INTO WEST-CENTRAL
WI. HOWEVER...EXPECT SECOND AREA OF MAINLY SHOWERS TO MOVE ACROSS
TAF AIRFIELDS OVERNIGHT INTO MONDAY MORNING. THERE ARE CURRENTLY
SOME EMBEDDED THUNDERSTORMS ACROSS NORTHERN IA INTO SOUTH-CENTRAL
MN...BUT EXPECT SPATIAL COVERAGE TO BE LIMITED AND WILL NOT
INCLUDE IN 17.06Z TAFS.
LOW CONFIDENCE ON CEILINGS/VISIBILITY GIVEN BROKEN NATURE OF
CONVECTION AND VARYING FORECAST GUIDANCE. FOR NOW...WILL CARRY
PREDOMINANT MVFR CONDITIONS THROUGH MUCH OF THE PERIOD GIVEN
UPSTREAM OBSERVATIONS...BUT THERE VERY WELL COULD BE PROLONGED
PERIODS OF VFR CONDITIONS IN THE MIX. THINK MOST OF THE
PRECIPITATION WILL END MONDAY MORNING...BUT ADDITIONAL CONVECTIVE
CHANCES EXIST INTO MONDAY AFTERNOON. LIGHT SOUTH-SOUTHWEST WIND
WILL SHIFT TO THE NORTH-NORTHWEST AFTER FRONTAL PASSAGE.
&&
.HYDROLOGY...
ISSUED AT 348 AM CDT MON AUG 17 2015
DECENT RAINFALL AMOUNTS ARE EXPECTED WITH THE UPCOMING SYSTEM FROM
LATE TONIGHT THROUGH WEDNESDAY. CURRENTLY EXPECTING RAINFALL
AMOUNTS OF 1 TO 1.5 INCHES OVER THIS SPREAD OUT PERIOD. THESE
AMOUNTS AND THE SOMEWHAT EXTENDED TIME FRAME OVER WHICH THEY ARE
EXPECTED...SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING
PROBLEMS...ESPECIALLY GIVEN THE RECENT DRY CONDITIONS THAT HAVE
DEVELOPED. NOT ANTICIPATING THE NEED FOR ANY HYDROLOGIC HEADLINES
FROM THIS SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...ROGERS
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
343 AM CDT MON AUG 17 2015
.SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE MAIN FOCUS INTO TONIGHT IS ON A COLD FRONT THAT STALLS OUT OVER
THE REGION AND WHEN/IF WE WILL GET RAIN SHOWERS/CONVECTION AHEAD OF
IT.
CURRENTLY...THIS COLD FRONT EXTENDS FROM EASTERN LAKE SUPERIOR
SOUTHWEST INTO CENTRAL IOWA WHICH IS JUST UPSTREAM FROM AN ELONGATED
MID LEVEL SHORT WAVE TROUGH NOTED ON WATER VAPOR IR/RAP ANALYSIS.
RAIN SHOWERS/CONVECTION HAS DEVELOPED AHEAD OF THE FRONT...BUT SEEMS
TO BE GOING A TAD SLOWER THAN PREVIOUS GUIDANCE HAD SUGGESTED.
THUS...HAVE SLOWED DOWN THE EASTWARD PROGRESSION OF THE RAIN SHOWERS
THIS MORNING.
17.07Z RAP SOUNDINGS SHOW A SKINNY CAPE PROFILE FOR TODAY AHEAD OF
THE FRONT WITH LITTLE TO NO 0-6KM WIND SHEAR...SO AM NOT EXPECTING
ANY SEVERE WEATHER WITH CONVECTION TODAY. THE 17.00Z NAM SEEMS TO
BE OVERDONE WITH THE BAND OF HIGH INSTABILITY AND RESULTANT
CONVECTION THAT IT DEVELOPS INTO FAR SOUTHEASTERN WISCONSIN THIS
AFTERNOON. WHILE IT DOES LOOK LIKE WE WILL SEE SOME WARMING THIS
MORNING IN THE WARM SECTOR...THE NAM BRINGS SURFACE DEW POINTS UP
INTO THE MID 70S IN THIS BAND WHERE MID TO UPPER 60S WILL BE MORE
LIKELY. THE COLD FRONT SHOULD FEATURE SOME RAIN SHOWERS/STORMS AS
IT COMES THROUGH THIS AFTERNOON/EVENING ALONG WITH THE MID LEVEL
SHORT WAVE TROUGH...IT IS JUST HOW MUCH WILL WE SEE. ACTIVITY
SHOULD LESSEN TONIGHT AS THE BETTER FORCING SHIFTS OFF TO THE EAST
AND THE SURFACE FRONT STALLS.
.LONG TERM...
TUESDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE MEDIUM.
AN AMPLIFIED UPPER TROUGH DIGGING INTO THE CENTER OF THE COUNTRY
WILL BRING A POTENT SURFACE LOW TO THE MIDWEST TUESDAY NIGHT THROUGH
WEDNESDAY. THE 850MB BAROCLINIC ZONE WILL BE STALLED IN SOUTHERN WI.
UPPER DIVERGENCE FROM THE RIGHT ENTRANCE REGION OF THE UPPER JET
WILL LINGER OVER SOUTHERN WI ALL DAY TUESDAY. THE NOSE OF THE LOW
LEVEL JET SHOULD BRIEFLY POINT INTO SOUTHERN WI LATE TUESDAY
AFTERNOON/EARLY EVENING... SO THIS WILL BE OUR BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS.
THIS IS A PARTICULARLY STRONG SYSTEM FOR THIS TIME OF YEAR.
HOWEVER... WEAK MID LEVEL LAPSE RATES WILL KEEP CAPE/INSTABILITY ON
THE LOW SIDE... BUT SHEAR WILL BE MODERATE TO STRONG ESPECIALLY IN
THE LOW LEVELS. THIS SYSTEM HAS THE POTENTIAL FOR ISOLATED SEVERE
WEATHER SO SPC HAS THE MKX AREA IN A MARGINAL RISK WITH A SLIGHT
RISK IN THE FAR SOUTHWEST COUNTY WARNING AREA.
EXPECT THE DRY SLOT/COLD FRONT TO MOVE ACROSS SOUTHERN WI EARLY
WEDNESDAY MORNING. WESTERLY WINDS ON WEDNESDAY WILL BE GUSTY...
ALTHOUGH THERE IS MODEL UNCERTAINTY FOR HOW HIGH THE WINDS WILL BE.
THURSDAY THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM.
THE UPPER LOW WILL TAKE ITS TIME EXITING THE GREAT LAKES REGION. A
HIGH PRESSURE RIDGE WILL SPREAD IN THU NIGHT. MODELS ARE SHOWING
WISCONSIN DRY WITH MOSTLY CLEAR SKIES FOR THIS PERIOD.
SATURDAY THROUGH MONDAY... FORECAST CONFIDENCE MEDIUM.
A LOW PRESSURE TROUGH WILL CROSS THE UPPER MIDWEST/SOUTHERN CANADA
OVER THE WEEKEND. THE TRAILING COLD FRONT WILL BRING A CHANCE FOR
SHOWERS AND THUNDERSTORMS TO WISCONSIN SATURDAY NIGHT INTO SUNDAY.
&&
.AVIATION/12Z TAFS/...
SOME GUSTY CONDITIONS OF UP TO 20KT ARE POSSIBLE THIS
MORNING/AFTERNOON AHEAD OF A COLD FRONT WHICH WILL STALL OUT ACROSS
THE REGION TONIGHT. RAIN SHOWERS AND THUNDERSTORMS ARE LIKELY THIS
AFTERNOON INTO THIS EVENING WITH SOME BRIEF DROPS IN VISIBILITY
POSSIBLE WITH THEM. IF RAIN DOES FALL TODAY...THERE COULD BE SOME
FOG THAT DEVELOPS TONIGHT WITH WINDS GOING LIGHT ALONG THE STALLING
OUT COLD FRONT...BUT SKIES SHOULD BE CLOUDY WHICH MAY LIMIT HOW MUCH
RADIATIONAL COOLING OCCURS.
&&
.MARINE...
WINDS WILL SHIFT FROM THE SOUTHWEST TO THE NORTH BEFORE BECOMING
LIGHT AND VARIABLE TONIGHT AS A COLD FRONT MOVES DOWN INTO THE
REGION AND STALLS OUT. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
AHEAD OF THE FRONT WITH SOME GUSTY WINDS ACCOMPANYING A FEW OF THE
THUNDERSTORMS. WINDY CONDITIONS ARE EXPECTED ON WEDNESDAY AS A LOW
PRESSURE SYSTEM MOVES THROUGH THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HALBACH
TUESDAY THROUGH SUNDAY...MRC
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
750 AM MDT MON AUG 17 2015
.UPDATE...
ISSUED AT 750 AM MDT MON AUG 17 2015
SURFACE BOUNDARY THAT CUTS ACROSS THE SRN PORTION OF THE FORECAST
AREA HAS BEEN THE TRIGGER MECHANISM FOR ISOLATED SHOWERS AND
THUNDERSTORMS. THE HRRR MODEL SHOWS ACTIVITY EXPANDING ACROSS THIS
AREA AS THE DAY PROGRESSES...BUT A BIT SLOW HANDLING THE CURRENT
ACTIVITY.
THE OTHER CONCERN IS THE POTENTIAL FOR RED FLAG CONDITIONS ACROSS
NW COLORADO...SPECIFICALLY ZONE 200. RAP13 SHOWING DEEPENING SURFACE
LOW (SUB 1000 MB) FROM RAWLINS TRAILING BACK TO SOUTHEAST UTAH.
UPSTREAM...THERE IS THERMAL GRADIENT THAT SPREADS INTO NW COLORADO
THIS EVENING. THE HRRR MODEL SHOWS SURFACE WINDS 15-20 KTS ACROSS
NW COLORADO THIS AFTERNOON. WITH DEEP MIXED LAYER...EXPECT GUSTY
WINDS TO DEVELOP. FIRST IMPRESSION IS THAT RED FLAG CONDITIONS
WILL BE MET...AT LEAST FOR FIRE WEATHER ZONE 200 AND POSSIBLY 202.
PLAN TO TAKE ANOTHER LOOK AT THIS ONCE 12Z GUIDANCE ARRIVES BEFORE
MAKING A FINAL DECISION.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
DRIER AIR BEGINS TO WORK ACROSS NORTHEAST UTAH AND NORTHWEST
COLORADO THIS AFTERNOON AS A 85 KT UPPER LEVEL JET REMAINS OVERHEAD.
THE BEST MOISTURE IS ALONG THE BOOKCLIFFS AND SOUTH ACROSS SOUTHEAST
UTAH AND SOUTHWEST COLORADO WHERE PRECIPITABLE WATER (PW) VALUES
RANGE FROM 0.75 TO 1.0 INCH. EXPECTING STORMS TO DEVELOP OVER THE
HIGHER TERRAIN BY LATE MORNING/EARLY AFTERNOON ACROSS WEST CENTRAL
AND SOUTHWEST COLORADO WITH STORMS DRIFTING AND IMPACTING VALLEYS BY
MID AFTERNOON THROUGH EARLY EVENING GIVEN SOME DECENT STORM MOTION
FROM WEST TO EAST AT 20 MPH. THERE IS SOME DECENT INSTABILITY AND
SHEAR SO EXPECTING SOME ROTATING STORMS WITH GOOD SUSTAINING
UPDRAFTS SIMILAR TO SUNDAY`S ENVIRONMENT. MAINLY BRIEF HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS CAN BE EXPECTED WITH
FREQUENT LIGHTNING.
AN UPPER LEVEL LOW PRESSURE TROUGH WILL MOVE THROUGH MONTANA AND
NORTHEAST WYOMING THIS AFTERNOON AND EVENING WITH AN ASSOCIATED COLD
FRONT MOVING THROUGH THIS EVENING. THERE IS A NOTICEABLE WIND SHIFT
FROM WEST TO NORTHWEST AS WELL AS A DECREASE IN PW VALUES BEHIND
THIS FRONT TO 0.25 TO 0.5 INCH RANGE. THE SHORT TERM MODELS ARE IN
PRETTY GOOD AGREEMENT WITH TIMING OF THE FRONT WHICH SHOW THE
FRONT MOVING THROUGH THE AREA THIS EVENING INTO EARLY TUESDAY
MORNING. FOLLOWED NAM12 GUIDANCE FOR TIMING WHICH SHOWS THE FRONT
THROUGH NE UTAH AND NW COLORADO BETWEEN 6 PM AND 9 PM AND THROUGH
SE UTAH AND WEST CENTRAL COLORADO BETWEEN 9 PM AND MIDNIGHT. THE
FRONT WILL BE EXITING THE REST OF THE AREA BY 3 AM. THE MODELS ARE
NOT PERFECT SO THIS TIMING MAY NOT BE EXACT BUT AT THIS TIME...IT
GIVES A GOOD APPROXIMATION.
ANOTHER CONCERN IS THE POTENTIAL FOR FIRE WEATHER CRITERIA TO BE MET
ACROSS NORTHWEST COLORADO LATE THIS AFTERNOON AND EVENING WHERE
DRIER AIR WILL BE IN PLACE. THE TIMING OF THE COLD FRONT IS
CRITICAL FOR WHEN AND IF RED FLAG CRITERIA WILL BE MET...WHICH AT
THIS TIME SEEMS TOO LATE IN THE DAY. FIRE WEATHER CONDITIONS LOOK
TO BE FAIRLY LOCALIZED AND NOT WIDESPREAD ENOUGH FOR A LONG ENOUGH
DURATION TO ISSUE ANY FIRE WEATHER HIGHLITES AT THIS TIME. SEE
FIRE WEATHER DISCUSSION BELOW FOR MORE DETAILS.
SHOWERS AND STORMS WILL END AFTER SUNSET AS THIS FRONT MOVES THROUGH
THE REGION FOR A COOLER AND CLEAR NIGHT. TUESDAY WILL BE MUCH DRIER
WITH LITTLE IN THE WAY OF STORM ACTIVITY EXPECTED. ANOTHER UPPER
LEVEL DISTURBANCE WILL MOVE THROUGH MONTANA AND NE WYOMING
TUESDAY AFTERNOON/EVENING PROVIDING A REINFORCING SHOT OF COOLER
AIR TUESDAY NIGHT. EXPECT COOLER TEMPERATURES ON TUESDAY IN THE
WAKE OF THE COLD FRONT WITH HIGHS A FEW DEGREES BELOW NORMAL.
WINDS WILL BE BREEZY TUESDAY AFTERNOON ESPECIALLY ACROSS SW
COLORADO WHERE LOCALIZED FIRE WEATHER CONDITIONS ARE POSSIBLE.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
MODERATE NORTHWEST FLOW WILL CONTINUE INTO TUE NIGHT AND ANOTHER
SHORTWAVE TROUGH WILL SLIDE JUST EAST OF THE FORECAST AREA. FIRE
WEATHER CONCERNS WILL CONTINUE...ESPECIALLY OVER NW CO...BUT THE
TIGHTEST GRADIENT WILL HOLD OFF UNTIL AFTER MIDNIGHT AND AFTER
THE HUMIDITY WILL HAVE RISEN ABOVE CRITERIA.
WED AND THU...THE GRADIENT RELAXES AS LOW PRESSURE PUSHES TO THE
EAST AND DRY CONDITIONS PREVAIL. ON FRIDAY AND SATURDAY ANOTHER
TROUGH WILL MOVE ACROSS THE NORTHERN TIER STATES. THE GFS AND EC
ARE FINALLY SHOWING SOME AGREEMENT AND RUN TO RUN CONSISTENCY.
BOTH KEEP THE TROUGH CLOSER TO THE U.S. AND CANADIAN BORDER...
THOUGH THE PRESSURE GRADIENT OVER THE FORECAST AREA WILL INCREASE
FRIDAY NIGHT THROUGH SAT EVENING AND SOME MOISTURE WILL BE DRAWN
NORTH FROM AZ AND NM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 357 AM MDT MON AUG 17 2015
VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES FOR THE NEXT 24
HOURS. A WEAK COLD FRONT MOVING THROUGH THE AREA THIS MORNING
WILL CAUSE A BAND OF ISOLATED SHOWERS AND THUNDERSTORMS CUTTING
ACROSS CENTRAL AND SOUTHWEST CO. KMTJ AND KTEX SHOULD HAVE VCSH
THROUGH ABOUT 15Z.
FROM 19Z TO ABOUT 04Z ANOTHER WEAK FRONT WILL MOVE ACROSS THE
AREA FROM NW TO SE. ISOLD TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL DEVELOP ALONG WITH GUSTY NORTHWEST WINDS. EXPECT MECHANICAL
TURBULENCE OVER RIDGES.
&&
.FIRE WEATHER...
ISSUED AT 357 AM MDT MON AUG 17 2015
AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE NORTHERN ROCKIES
THIS AFTERNOON AND EVENING WITH A COLD FRONT MOVING THROUGH EASTERN
UTAH AND WESTERN COLORADO DURING THE EVENING HOURS. BREEZY
CONDITIONS WILL EXIST ACROSS NORTHWEST COLORADO DURING THE AFTERNOON
AND EVENING WITH THE BEST WINDS OCCURRING BETWEEN 6 PM AND 9 PM. THE
KEY PIECE HERE IS THE TIMING OF A COLD FRONT WHICH LOOKS TO MOVE
THROUGH NORTHWEST COLORADO BETWEEN 6 PM AND 9 PM THIS EVENING.
LOCALIZED FIRE WEATHER CONDITIONS ARE POSSIBLE DURING THIS TIME BUT
DOES NOT LOOK WIDESPREAD ENOUGH FOR A LONG ENOUGH DURATION TO ISSUE
FIRE WEATHER HIGHLITES. THE FRONTAL TIMING IS A BIT TOO LATE WHEN
THE COMBINATION OF LOW RH AND WINDS TO 25 MPH WILL BE MET. THIS IS
SOMETHING THAT BEARS WATCHING DEPENDING ON THE TIMING OF THE COLD
FRONT. TUESDAY WILL BE DRIER ACROSS THE REGION WITH BREEZY
CONDITIONS POSSIBLE FOR SW COLORADO WHICH ALSO BEARS WATCHING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
UPDATE...PF
SHORT TERM...MDA
LONG TERM...CC
AVIATION...CC
FIRE WEATHER...MDA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1045 AM EDT MON AUG 17 2015
.DISCUSSION...
MORNING CAPE SOUNDING SHOWS A SLIGHTLY DRIER AIRMASS BUT PWATS
REMAIN A MOIST 1.97 INCHES THROUGH THE COLUMN. HOWEVER...THERE IS A
DRY LAYER AT 850 MB WHICH IS LIMITING SHOWER ACTIVITY OVER THE ATLC
AND SHOULD DELAY SLIGHTLY CONVECTIVE DEVELOPMENT OVER LAND. A FEW
ATLC SHOWERS PUSHED ONSHORE MARTIN COUNTY EARLIER THIS MORNING BUT
THESE HAVE DIMINISHED. WITH THE LOW LEVEL RIDGE AXIS TO OUR NORTH...
THE EAST COAST SEA BREEZE WILL DEVELOP EARLY AND PUSH INLAND
STEADILY. THE SUBSIDENCE BEHIND THE SEA BREEZE SHOULD SUPPRESS
ADDITIONAL SHOWERS FROM PUSHING ONSHORE SO RAIN CHANCES APPEAR
LOWEST ALONG THE COAST GOING FORWARD. HAVE LOWERED POPS OVER THE
ATLC AND COAST SLIGHTLY TO 25 PERCENT. WILL KEEP A LITTLE HIGHER
RAIN CHANCE ALONG THE VOLUSIA COAST WHERE RAP ANALYSIS SHOWS VORT
MAX PUSHING OFF THE COAST AND VIS SATELLITE IMAGERY SHOWING A TWIST
TO THE MID LEVEL CLOUD PATTERN. EXPECT ISOLATED TO SCATTERED
SHOWERS/STORMS TO DEVELOP INLAND FROM THE COAST AND INCREASING IN
COVERAGE OVER THE INTERIOR ESP NORTH AND WEST OF ORLANDO. THE SEA
BREEZE COLLISION SHOULD OCCUR JUST WEST OF LAKE COUNTY EARLY THIS
EVENING SO WILL KEEP SCATTERED SHOWERS WEST OF ORLANDO PAST SUNSET.
&&
.AVIATION...VFR MAY GIVE WAY TO LCL-AREAS MVFR CIGS BKN020-025 AFTER
15Z IN DIURNAL CU BUT DRY AIR SEEN AT 5K FT FROM WEATHER BALLOON MAY
LIMIT SPATIAL COVERAGE. ISOLD SHRA/TS INLAND FROM THE COAST 15Z-18Z
AS ECSB DEVELOPS. ACTIVITY CONCENTRATES OVER THE INLAND TERMINALS
20Z-24Z...WITH SPOTTY ACTIVITY TIL AROUND 02Z ESP LEE.
&&
.MARINE... NO SIGNIFICANT CHANGES TO CURRENT COASTAL WATERS FCST.
TODAY/TONIGHT...RIDGE AXIS NORTH OF THE WATERS WILL GENERATE A
GENTLE E-SE BREEZE AROUND 10 KNOTS THROUGH TONIGHT WITH SEAS A
LITTLE EITHER SIDE OF 2 FEET.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 90 75 90 76 / 50 20 40 20
MCO 92 75 93 76 / 60 20 60 30
MLB 90 76 90 78 / 30 20 40 20
VRB 90 75 90 76 / 30 20 40 30
LEE 91 76 94 78 / 60 30 60 30
SFB 92 75 93 76 / 60 20 50 30
ORL 92 76 93 77 / 60 20 60 30
FPR 90 75 90 76 / 30 20 40 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
KELLY/BRAGAW
AREA FORECAST DISCUSSION
NWS WICHITA KS
620 AM CDT MON AUG 17 2015
...UPDATED FOR 12Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 317 AM CDT MON AUG 17 2015
CONVECTION IS DECREASING IN AREAL EXTENT BUT CONTINUING ACROSS
SOUTHWEST KANSAS AND OVER NORTH CENTRAL KANSAS AND NORTHEAST INTO
SOUTHEAST NEBRASKA. THIS SCATTERED CONVECTION IS EXPECTED TO
LINGER...BUT DIMINISH INTO THE EARLY MORNING HOURS.
BILLINGS WRIGHT
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
TODAY - TONIGHT: THE HIGH RESOLUTION GUIDANCE HRRR AND THE HIGHER
RESOLUTION NAM12 STRUGGLE TO SHOW MUCH CONVECTION PERSISTING
ACROSS CENTRAL KANSAS DURING THE EARLY PART OF THE DAY. A PIECE
OF ENERGY WILL APPROACH THE AREA FROM THE NORTHWEST DURING THE
LATE AFTERNOON HOURS WHICH WILL INCREASE THE CHANCES FOR
CONVECTION INTO THE EVENING ESPECIALLY OVER CENTRAL AND SOUTH
CENTRAL KANSAS. SHEAR WILL BE LACKING...BUT THERE IS A MODEST
1000-1500 J/KG CAPE FOR THUNDERSTORMS TO POTENTIALLY BE
STRONG...AND WITH THE WEAK FLOW...FLOODING COULD BE A CONCERN AS
WELL. MOISTURE TRANSPORT INCREASES DURING THE OVERNIGHT HOURS
INCREASING THE PRECIPITATION CHANCES FOR SOUTH CENTRAL KANSAS.
TUESDAY - WEDNESDAY:
THE STRONGER UPPER LEVEL WAVE WILL MOVE INTO THE REGION DURING THE
DAY TUESDAY...BUT THE MAIN FRONTAL PUSH WILL BE LATER TUESDAY
EVENING WHEN THE UPPER LOW DIGS SLIGHTLY DEEPER. THE UPPER PV
ENERGY MOVING ACROSS THE AREA TUESDAY WILL INCREASE THE CHANCE
FOR THUNDERSTORMS THROUGHOUT THE DAY. THE UPPER WAVE WILL BE
CLOSER TO KANSAS INCREASING THE UPPER SHEAR PROFILE. SEVERE STORMS
MAY BE POSSIBLE ESPECIALLY OVER CENTRAL AND NORTHERN PORTIONS OF
SOUTH CENTRAL KANSAS WHERE THE COMBINATION OF SHEAR AND
INSTABILITY ARE ANTICIPATED TO BE THE GREATEST. ELSEWHERE STORMS
COULD BE STRONG.
BY TUESDAY NIGHT THE MAIN COLD FRONT/WIND SHIFT WILL BEGIN MOVING
ACROSS CENTRAL AND EASTERN KANSAS. THUNDERSTORMS ALONG THE FRONT
ARE POSSIBLE...BUT THE CONVERGENCE ISN`T OVERWHELMING. THE FRONT
IS EXPECTED TO BE FAIRLY PROGRESSIVE AND MOVE THROUGH THE AREA BY
EARLY MORNING WEDNESDAY. A FEW STRONGER STORMS REMAIN POSSIBLE
ALONG THE FRONT.
A SECONDARY PIECE OF ENERGY WILL MOVE SOUTHWARD INTO THE UPPER LOW
CAUSING THE POTENTIAL FOR SCATTERED SHOWERS DURING THE DAY
WEDNESDAY.
THE FRONT WILL CAUSE TEMPERATURES ON WEDNESDAY TO BE SIGNIFICANTLY
COOLER THAN RECENT DAYS...STEADILY COOLING FROM A HIGH CLOSE TO
NORMAL TODAY IN THE LOW 90S TO THE LOW TO MID 70S BY WEDNESDAY.
BILLINGS WRIGHT
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
WHILE THERE ARE SOME SLIGHT DISCREPANCIES AMONGST THE MEDIUM
RANGE GUIDANCE...THE PATTERN REMAINS ACTIVE AND GENERALLY IN
FAIRLY GOOD AGREEMENT. ZONAL FLOW WILL RETURN BRIEFLY AHEAD OF THE
NEXT SYSTEM FOR THE WEEKEND...BUT BEFORE THAT A WEAK TROUGH WILL
IMPACT THE AREA FOR THE END OF THE WEEK.
THE WEAK TROUGH MAY BRING CHANCES FOR RAIN THURSDAY NIGHT AND
FRIDAY...BUT CONFIDENCE IS LOWER DUE TO DISCREPANCIES.
TEMPERATURES WILL STEADILY INCREASE BACK INTO THE 80S...BUT THE
NEXT FRONT WILL APPROACH AND TRAVERSE THE AREA SATURDAY
NIGHT/SUNDAY MORNING. THIS FRONT WILL BRING THE NEXT BEST CHANCE
OF RAIN TO THE REGION. THIS PERIOD HAS HIGHER CONFIDENCE DUE TO
BETTER AGREEMENT ACROSS VARIOUS MODEL SOLUTIONS.
BILLINGS WRIGHT
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 613 AM CDT MON AUG 17 2015
MAIN AVIATION CONCERNS WILL BE CONVECTIVE TRENDS OVER THE NEXT 24
HOURS.
A CLUSTER OF SHOWERS AND STORMS SLOWLY TRACKED SOUTH ACROSS
WESTERN KS OVERNIGHT WITH A REMNANT MCV NOW SITUATED OVER
WESTERN OK. THE COLD FRONT THAT SWEPT ACROSS THE NORTHERN PLAINS
YESTERDAY HAS STARTED TO WASH OUT AND WHAT IS LEFT OF IT CURRENTLY
STRETCHES FROM NORTHEAST IA INTO WESTERN KS. THIS FEATURE WILL
CONTINUE TO WASH OUT TODAY. WITH LACK OF A SURFACE
FOCUS...CONVECTIVE TRENDS TODAY WILL BE TOUGH WITH THE MAIN
FORCING THE RESULT OF INCREASING UPPER DIFFLUENCE AS A WEAK WAVE
APPROACHES. WITH LACK OF CONFIDENCE WILL LEAVE OUT MENTION OF
STORMS TODAY. HOWEVER...CONFIDENCE IN STORMS INCREASES TONIGHT AS
850MB FLOW VEERS WHICH WILL SET UP SOME DECENT 850-700MB MOISTURE
TRANSPORT. SO WILL RUN WITH VCTS AT ALL SITES AFTER 06Z TONIGHT.
LAWSON
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 90 71 84 60 / 40 50 60 70
HUTCHINSON 90 70 85 58 / 40 50 50 60
NEWTON 89 69 84 57 / 40 50 50 70
ELDORADO 90 71 84 58 / 40 50 60 70
WINFIELD-KWLD 91 71 85 60 / 40 50 60 70
RUSSELL 88 66 83 54 / 50 50 60 30
GREAT BEND 89 68 85 55 / 50 50 60 40
SALINA 90 70 85 57 / 40 50 60 50
MCPHERSON 90 70 85 57 / 40 50 50 60
COFFEYVILLE 91 72 86 64 / 20 40 60 70
CHANUTE 90 72 84 61 / 30 40 60 70
IOLA 90 71 83 61 / 30 40 60 70
PARSONS-KPPF 91 71 85 62 / 20 30 60 70
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
840 AM EDT MON AUG 17 2015
...FORECAST UPDATE...
ISSUED AT 840 AM EDT MON AUG 17 2015
DID A QUICK UPDATE TO INCREASE POPS ACROSS THE SOUTH WHERE LIGHT
RAIN IS NOW MOVING IN. MESONET SITES NEAR THE TN BORDER HAVE
RECORDED A HUNDREDTH OR TWO, WITH ADDITIONAL STRONGER REFLECTIVITIES
IN BETWEEN OBSERVATION LOCATIONS.
ALSO ADDED SOME SPRINKLES IN SUB-15% POP AREAS. HAD SOME SPRINKLES
IN THE LOUISVILLE METRO OVER THE PAST HOUR.
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
MOISTURE WILL CONTINUE TO ADVECT INTO THE REGION FROM THE SOUTH THIS
PERIOD. AN UPPER LEVEL LOW NOW ALONG THE SOUTHERN IN/IL BORDER WILL
TRAVEL NORTH AND THEN START HEADING NORTHEAST BY LATER THIS
AFTERNOON. ALREADY SEEING SOME LIGHT RADAR RETURNS OVER SOUTH
CENTRAL TN THIS HOUR...IN AN AREA OF ENHANCED LIFT ON THE SOUTH SIDE
OF A WEAK UPPER JET. THESE RAINS SHOULD LIFT NORTHWARD THIS MORNING.
ANOTHER AREA OF SHOWERS SHOULD DEVELOP ALONG THE OHIO RIVER THIS
MORNING...WHERE THE LATEST RAP PLACES A THETA-E RIDGE.
THE CHANCE FOR AFTERNOON THUNDERSTORMS WILL DEPEND PARTLY ON HOW
MANY BREAKS WE GET IN THE CLOUDS TODAY. IT WILL NOT TAKE MUCH...AS
COOLER AIR ALOFT WITH THE PASSAGE OF THE UPPER LOW WILL MEAN SOME
ELEVATED INSTABILITY AS WELL. GIVEN THE CLOUD COVER THOUGH...THINK
THE RISK FOR SEVERE WEATHER IS FAIRLY LOW.
TONIGHT THAT WAVE SHOULD BE HEADING TOWARD NORTHERN OHIO. THAT SAID
THOUGH...IT WILL LEAVE A TRAILING TROUGH THAT MAY ALLOW FOR
CONTINUED STORM DEVELOPMENT OVER THE SOUTHEAST HALF OF OUR FORECAST
AREA. THAT AREA WILL CONTINUE TO SEE THE BEST CHANCES ON TUESDAY.
MAY HAVE TO MONITOR FOR FLOOD THREAT DOWN THERE AS OUR SOUTHEAST
COUNTIES HAVE LOWER FLASH FLOOD GUIDANCE. STILL CURRENT QPF IS WELL
BELOW THAT GUIDANCE, BUT SHOULD LATER FORECASTS TREND UP MORE WE
MAYNEED A WATCH.
CLOUD COVER SHOULD LIMIT HIGH TEMPERATURES TO BELOW NORMAL TODAY AND
TUESDAY...WHEREAS LOWS WILL BE A LITTLE ABOVE NORMAL. ONLY OTHER
CONCERN WOULD BE PATCHY FOG BOTH THIS MORNING AND TOMORROW MORNING,
WITH COVERAGE LIMITED BOTH DAYS ALSO BY CLOUD COVER.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
TUESDAY NIGHT...
WEAK SOUTHWEST FLOW WILL BE IN PLACE AHEAD OF A STRONG NORTH CENTRAL
CONUS TROUGH TO START THE LONG TERM. MAINLY DIURNALLY DRIVEN
SCATTERED T-STORMS ARE EXPECTED TO BE ONGOING ACROSS OUR SE CWA
TUESDAY EVENING, HOWEVER THESE SHOULD GRADUALLY DIMINISH AS WE HEAD
INTO THE OVERNIGHT HOURS. CAN`T GO COMPLETELY DRY AS THERE IS A
SIGNAL FOR SOME LOW LEVEL JETTING THROUGH THE OVERNIGHT. SOUTHERLY
WINDS SHOULD INCREASE TOWARD DAWN, HELPING LOWS TO STAY ON THE MILD
SIDE. LOOK FOR MAINLY LOW 70S.
WEDNESDAY - THURSDAY...
STRONG SHORTWAVE TROUGH AND ITS ASSOCIATED SURFACE LOW WILL MOVE
FROM THE UPPER MIDWEST TO LAKE SUPERIOR BY LATE WEDNESDAY NIGHT.
DEEP MOISTURE WILL POOL INTO THE OHIO RIVER VALLEY AHEAD OF THE
TROUGH AND SURFACE FRONT TRAILING FROM THE LOW. MEANWHILE, STRONGER
DEEP FLOW WILL ALSO OVERSPREAD THE REGION BY WEDNESDAY NIGHT. LOOK
FOR SCATTERED TO NUMEROUS THUNDERSTORMS DURING THE DAY ON WEDNESDAY
WITH HIGHS MAINLY IN THE LOW 80S. A FEW OF THE STORMS COULD BE
STRONG IF MODERATE INSTABILITY IS REALIZED, ALTHOUGH BETTER DEEP
SHEAR AND FORCING DOESN`T ARRIVE UNTIL LATER WEDNESDAY NIGHT. WE`LL
HAVE TO CONTINUE TO KEEP AN EYE ON POTENTIAL FOR AN ORGANIZED SEVERE
THREAT LATER WEDNESDAY EVENING INTO WEDNESDAY NIGHT, ALTHOUGH SOME
LIMITING FACTORS COULD BE TIMING OF PASSAGE/MORE LIMITED INSTABILITY
AND BEST FORCING NORTH OF THE CWA. WILL CONTINUE TO MENTION HEAVY
RAIN AND GUSTY WINDS AS THE MAIN POTENTIAL THREATS IN THE HWO.
COLD FRONT LOOKS TO PASS THROUGH EARLY THURSDAY MORNING ACROSS THE
NW AND THROUGH MOST OF THE CWA BY LATE THURSDAY MORNING. IF PASSAGE
IS SLOW ENOUGH, SOME REDEVLOPMENT COULD OCCUR ACROSS OUR FAR E OR SE
THURSDAY AFTERNOON, WHERE SOME STRONGER/PULSY STORMS WOULD BE
POSSIBLE. OTHERWISE, SKIES WILL BECOME GRADUALLY CLEARER WITH
TEMPERATURES ONLY TOPPING OUT IN THE MID OR UPPER 70S.
THURSDAY NIGHT - SUNDAY...
THE FRONT COULD HANG UP ACROSS OUR SOUTH TO END THE WEEK AND HEAD
INTO THE WEEKEND SO WILL KEEP ISOLATED TO WIDELY SCATTERED CHANCES
ACROSS THE SOUTH THROUGH SATURDAY. THE NORTH WILL BE DRY DURING THIS
TIME CLOSER TO THE SURFACE HIGH CENTER. THURSDAY NIGHT LOWS LOOK TO
DROP INTO THE UPPER 50S NORTH AND LOWER 60S SOUTH THURSDAY NIGHT.
CAN`T RULE OUT A FEW MID 50S IN OUR TYPICAL COOL NORTH SPOTS. HIGHS
ON FRIDAY WILL MODERATE A BIT, FINDING THEIR WAY BACK TO THE LOW
80S. FRIDAY NIGHT WILL BE SLIGHTLY MILDER WITH LOWS BACK IN THE LOW
AND MID 60S. SATURDAY BRINGS HIGHS IN THE LOW AND MID 80S.
STORM CHANCES MAY INCREASE ON SUNDAY AHEAD OF ANOTHER MID LEVEL
DISTURBANCE AND ASSOCIATED SURFACE FRONT. HOWEVER, CONFIDENCE IS LOW
IN TIMING OF THIS FEATURE SO WILL ONLY MENTION LOW CHANCES AT THIS
TIME.
&&
.AVIATION (12Z TAF UPDATE)...
ISSUED AT 640 AM EDT MON AUG 17 2015
IMPRESSIVE PLUME OF MOISTURE STREAMING IN AND WRAPPING INTO AN UPPER
LOW CENTERED SOUTHERN ILLINOIS. LIGHT RAINS ARE STARTING TO FORM
EAST OF THIS FEATURE, WITH A FEW STRONGER CELLS EMBEDDED AND NEAR
KHOP. TIME-HEIGHT SECTIONS STILL ARE NOT SHOWING AS STRONG OF A LIFT
IN ASSOCIATION WITH THIS MOISTURE SO HAVE GONE WITH VICINITY SHOWER
WORDING FOR NOW...THOUGH CANNOT RULE OUT EMBEDDED OCCASIONAL
THUNDER.
CLOUD COVER THROUGH THE DAY SHOULD LIMIT INSTABILITY...BUT WITH
DISTURBANCES RIDING AROUND THE UPPER LOW CANNOT RULE OUT SOME STORMS
THIS AFTERNOON...SO WENT WITH VICINITY STORMS FOR ALL SITES. LOW
CLOUDS SHOULD FILL IN BY LATE IN THE PERIOD...WITH MVFR RESTRICTIONS
POSSIBLE AT KLEX/KSDF AND IFR POSSIBLE AT KBWG.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
UPDATE.........13
SHORT TERM.....RJS
LONG TERM......BJS
AVIATION.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
641 AM EDT MON AUG 17 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
MOISTURE WILL CONTINUE TO ADVECT INTO THE REGION FROM THE SOUTH THIS
PERIOD. AN UPPER LEVEL LOW NOW ALONG THE SOUTHERN IN/IL BORDER WILL
TRAVEL NORTH AND THEN START HEADING NORTHEAST BY LATER THIS
AFTERNOON. ALREADY SEEING SOME LIGHT RADAR RETURNS OVER SOUTH
CENTRAL TN THIS HOUR...IN AN AREA OF ENHANCED LIFT ON THE SOUTH SIDE
OF A WEAK UPPER JET. THESE RAINS SHOULD LIFT NORTHWARD THIS MORNING.
ANOTHER AREA OF SHOWERS SHOULD DEVELOP ALONG THE OHIO RIVER THIS
MORNING...WHERE THE LATEST RAP PLACES A THETA-E RIDGE.
THE CHANCE FOR AFTERNOON THUNDERSTORMS WILL DEPEND PARTLY ON HOW
MANY BREAKS WE GET IN THE CLOUDS TODAY. IT WILL NOT TAKE MUCH...AS
COOLER AIR ALOFT WITH THE PASSAGE OF THE UPPER LOW WILL MEAN SOME
ELEVATED INSTABILITY AS WELL. GIVEN THE CLOUD COVER THOUGH...THINK
THE RISK FOR SEVERE WEATHER IS FAIRLY LOW.
TONIGHT THAT WAVE SHOULD BE HEADING TOWARD NORTHERN OHIO. THAT SAID
THOUGH...IT WILL LEAVE A TRAILING TROUGH THAT MAY ALLOW FOR
CONTINUED STORM DEVELOPMENT OVER THE SOUTHEAST HALF OF OUR FORECAST
AREA. THAT AREA WILL CONTINUE TO SEE THE BEST CHANCES ON TUESDAY.
MAY HAVE TO MONITOR FOR FLOOD THREAT DOWN THERE AS OUR SOUTHEAST
COUNTIES HAVE LOWER FLASH FLOOD GUIDANCE. STILL CURRENT QPF IS WELL
BELOW THAT GUIDANCE, BUT SHOULD LATER FORECASTS TREND UP MORE WE
MAYNEED A WATCH.
CLOUD COVER SHOULD LIMIT HIGH TEMPERATURES TO BELOW NORMAL TODAY AND
TUESDAY...WHEREAS LOWS WILL BE A LITTLE ABOVE NORMAL. ONLY OTHER
CONCERN WOULD BE PATCHY FOG BOTH THIS MORNING AND TOMORROW MORNING,
WITH COVERAGE LIMITED BOTH DAYS ALSO BY CLOUD COVER.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
TUESDAY NIGHT...
WEAK SOUTHWEST FLOW WILL BE IN PLACE AHEAD OF A STRONG NORTH CENTRAL
CONUS TROUGH TO START THE LONG TERM. MAINLY DIURNALLY DRIVEN
SCATTERED T-STORMS ARE EXPECTED TO BE ONGOING ACROSS OUR SE CWA
TUESDAY EVENING, HOWEVER THESE SHOULD GRADUALLY DIMINISH AS WE HEAD
INTO THE OVERNIGHT HOURS. CAN`T GO COMPLETELY DRY AS THERE IS A
SIGNAL FOR SOME LOW LEVEL JETTING THROUGH THE OVERNIGHT. SOUTHERLY
WINDS SHOULD INCREASE TOWARD DAWN, HELPING LOWS TO STAY ON THE MILD
SIDE. LOOK FOR MAINLY LOW 70S.
WEDNESDAY - THURSDAY...
STRONG SHORTWAVE TROUGH AND ITS ASSOCIATED SURFACE LOW WILL MOVE
FROM THE UPPER MIDWEST TO LAKE SUPERIOR BY LATE WEDNESDAY NIGHT.
DEEP MOISTURE WILL POOL INTO THE OHIO RIVER VALLEY AHEAD OF THE
TROUGH AND SURFACE FRONT TRAILING FROM THE LOW. MEANWHILE, STRONGER
DEEP FLOW WILL ALSO OVERSPREAD THE REGION BY WEDNESDAY NIGHT. LOOK
FOR SCATTERED TO NUMEROUS THUNDERSTORMS DURING THE DAY ON WEDNESDAY
WITH HIGHS MAINLY IN THE LOW 80S. A FEW OF THE STORMS COULD BE
STRONG IF MODERATE INSTABILITY IS REALIZED, ALTHOUGH BETTER DEEP
SHEAR AND FORCING DOESN`T ARRIVE UNTIL LATER WEDNESDAY NIGHT. WE`LL
HAVE TO CONTINUE TO KEEP AN EYE ON POTENTIAL FOR AN ORGANIZED SEVERE
THREAT LATER WEDNESDAY EVENING INTO WEDNESDAY NIGHT, ALTHOUGH SOME
LIMITING FACTORS COULD BE TIMING OF PASSAGE/MORE LIMITED INSTABILITY
AND BEST FORCING NORTH OF THE CWA. WILL CONTINUE TO MENTION HEAVY
RAIN AND GUSTY WINDS AS THE MAIN POTENTIAL THREATS IN THE HWO.
COLD FRONT LOOKS TO PASS THROUGH EARLY THURSDAY MORNING ACROSS THE
NW AND THROUGH MOST OF THE CWA BY LATE THURSDAY MORNING. IF PASSAGE
IS SLOW ENOUGH, SOME REDEVLOPMENT COULD OCCUR ACROSS OUR FAR E OR SE
THURSDAY AFTERNOON, WHERE SOME STRONGER/PULSY STORMS WOULD BE
POSSIBLE. OTHERWISE, SKIES WILL BECOME GRADUALLY CLEARER WITH
TEMPERATURES ONLY TOPPING OUT IN THE MID OR UPPER 70S.
THURSDAY NIGHT - SUNDAY...
THE FRONT COULD HANG UP ACROSS OUR SOUTH TO END THE WEEK AND HEAD
INTO THE WEEKEND SO WILL KEEP ISOLATED TO WIDELY SCATTERED CHANCES
ACROSS THE SOUTH THROUGH SATURDAY. THE NORTH WILL BE DRY DURING THIS
TIME CLOSER TO THE SURFACE HIGH CENTER. THURSDAY NIGHT LOWS LOOK TO
DROP INTO THE UPPER 50S NORTH AND LOWER 60S SOUTH THURSDAY NIGHT.
CAN`T RULE OUT A FEW MID 50S IN OUR TYPICAL COOL NORTH SPOTS. HIGHS
ON FRIDAY WILL MODERATE A BIT, FINDING THEIR WAY BACK TO THE LOW
80S. FRIDAY NIGHT WILL BE SLIGHTLY MILDER WITH LOWS BACK IN THE LOW
AND MID 60S. SATURDAY BRINGS HIGHS IN THE LOW AND MID 80S.
STORM CHANCES MAY INCREASE ON SUNDAY AHEAD OF ANOTHER MID LEVEL
DISTURBANCE AND ASSOCIATED SURFACE FRONT. HOWEVER, CONFIDENCE IS LOW
IN TIMING OF THIS FEATURE SO WILL ONLY MENTION LOW CHANCES AT THIS
TIME.
&&
.AVIATION (12Z TAF UPDATE)...
ISSUED AT 640 AM EDT MON AUG 17 2015
IMPRESSIVE PLUME OF MOISTURE STREAMING IN AND WRAPPING INTO AN UPPER
LOW CENTERED SOUTHERN ILLINOIS. LIGHT RAINS ARE STARTING TO FORM
EAST OF THIS FEATURE, WITH A FEW STRONGER CELLS EMBEDDED AND NEAR
KHOP. TIME-HEIGHT SECTIONS STILL ARE NOT SHOWING AS STRONG OF A LIFT
IN ASSOCIATION WITH THIS MOISTURE SO HAVE GONE WITH VICINITY SHOWER
WORDING FOR NOW...THOUGH CANNOT RULE OUT EMBEDDED OCCASIONAL
THUNDER.
CLOUD COVER THROUGH THE DAY SHOULD LIMIT INSTABILITY...BUT WITH
DISTURBANCES RIDING AROUND THE UPPER LOW CANNOT RULE OUT SOME STORMS
THIS AFTERNOON...SO WENT WITH VICINITY STORMS FOR ALL SITES. LOW
CLOUDS SHOULD FILL IN BY LATE IN THE PERIOD...WITH MVFR RESTRICTIONS
POSSIBLE AT KLEX/KSDF AND IFR POSSIBLE AT KBWG.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........RJS
LONG TERM.........BJS
AVIATION..........RJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
ISSUED BY NATIONAL WEATHER SERVICE GAYLORD MI
1113 AM EDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1110 AM EDT MON AUG 17 2015
500 MB SHORTWAVE TROUGH MOVING FROM NE IOWA INTO WISCONSIN, IS
PRODUCING SHOWERS ALONG A COLD FRONT THAT STRETCHES FROM AROUND
CYXZ (WAWA) TO NEAR KLSE. THE NORTHERN END HAS DIMINISHED OVER THE
LAST FEW HOURS AS THE SYSTEM HAS BIFURCATED SOMEWHAT, BUT WITH THE
500 MB SHORTWAVE, A NEW AREA OF RAIN IS MOVING OUT OF CENTRAL
WISCONSIN AND INTO W AND C UPPER. THIS IS EXPECTED TO CONTINUE
INTO THE AFTERNOON, SO HAVE BUMPED UP THE POPS ALONG THE FRONT FOR
THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN
UPPER MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN
AND UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET
OVER NW ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER
MI. THE AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG
LINGERED OVER THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO
NEAR 40 KNOTS SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN
CWA OVERNIGHT NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCAPE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAIL WITH MAX TEMPS IN
THE LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW
TO THE LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT MON AUG 17 2015
SEASONABLY COOL WEATHER WILL PREVAIL FOR THE MIDDLE OF THE WEEK
AMIDST RAIN. TEMPS WILL INCH BACK TO ABOVE AVERAGE BY SATURDAY
BEFORE A COLD FRONT BRINGS A CHANCE FOR RAIN AND ANOTHER COOL-DOWN
ON SUNDAY.
TUESDAY...DEEP MID-LEVEL TROUGHING WILL BE ONGOING ACROSS THE
NORTHERN AND CENTRAL PLAINS BY TUESDAY MORNING...WITH A LEE CYCLONE
FORMING OVER THE CENTRAL HIGH PLAINS. MEANWHILE...THE COLD FRONT
THAT CROSSED THE AREA EARLIER TODAY WILL HAVE WASHED OUT ACROSS
NORTHERN WI...WITH THE H7 TO H8 FRONT LINGERING AS FAR NORTH AS THE
SOUTH-CENTRAL CWA. WIDESPREAD WAA AHEAD OF THE DEVELOPING LOW LOOKS
TO HOLD OFF UNTIL TUESDAY NIGHT...THOUGH MID-LEVEL FGEN BECOMES
APPARENT BY THE AFTERNOON. WITH MODELS BEGINNING TO BACK OFF ON THE
SOUTHWARD PUSH OF DEEP DRY AIR BEHIND THE FRONT TODAY...THINK THAT
AT LEAST SOME LIGHT RAIN WILL BE POSSIBLE BY TUESDAY AFTERNOON.
GIVEN THAT WAA/ISENTROPIC LIFT IS STILL MINIMAL...CONTINUED WITH
JUST SLIGHT CHANCES IN THE FORECAST.
TUESDAY NIGHT AND WEDNESDAY...LOW-LEVEL MOISTURE TRANSPORT AND
ISENTROPIC LIFT QUICKLY INCREASE TUESDAY EVENING AS THE SFC LOW
STRENGTHENS AND NEARS. THE MID-LEVEL SHORTWAVE BEGINS TO TAKE ON
MORE OF A NEGATIVE TILT BY THIS TIME...SENDING MUCH OF THE MID-LEVEL
Q-VECTOR CONV NNE ACROSS MN AND WESTERN LAKE SUPERIOR.
ADDITIONALLY...THE LEFT-EXIT OF A STRENGTHENING 110KT UPPER JET
STREAK WILL PASS WEST OF THE CWA. WITH PWATS SURPASSING 1.5 IN...A
BAND OF HEAVY RAIN SHOULD DEVELOP WEST OF THE CWA...POSSIBLY
CLIPPING THE FAR WEST. MEANWHILE...STEADY LIGHT TO MODERATE RAIN
ASSOCIATED WITH THE WAA IS EXPECTED FOR THE REMAINDER OF THE CWA
THROUGH THE NIGHT. DYNAMICS ARE FAVORABLE FOR POSSIBLE THUNDER
ACROSS THE WEST...WHILE MUCAPE OF AROUND 500 J/KG WILL BE ENOUGH FOR
SOME EMBEDDED THUNDER ACROSS THE EAST.
A RATHER PRONOUNCED MID-LEVEL DRY SLOT WILL QUICKLY SPREAD ACROSS
THE CWA FROM THE SW WEDNESDAY MORNING AS THE SFC LOW TRACKS NNE
ACROSS WESTERN LAKE SUPERIOR. STEEPENING MID-LEVEL LAPSE RATES AHEAD
OF THIS DRY SLOT WILL ALLOW FOR SOME EMBEDDED THUNDERSTORMS. SHOWERS
BECOME ISOLATED ACROSS THE CENTRAL UNDER THE DRY SLOT...BUT CONTINUE
FOR THE FAR WEST AND EAST DURING THE AFTERNOON. ALSO...S TO SW WINDS
LOOK TO GET QUITE GUSTY ACROSS THE CENTRAL AND EAST AHEAD OF AND
UNDER THE DRY SLOT.
WEDNESDAY NIGHT AND THURSDAY...WRAP AROUND MOISTURE WILL KEEP RAIN
CHANCES ACROSS MOST OF THE CWA...PARTICULARLY ALONG LAKE THE WEST
WIND BELTS OF LAKE SUPERIOR...THROUGH THURSDAY BEFORE SYNOPTIC
FORCING AND MOISTURE DEPART THURSDAY NIGHT. H8 TEMPS DOWN TO 5C
COMBINED WITH A STRONG GRADIENT FLOW AND RELATIVELY WARM LAKE TEMPS
WILL ALLOW FOR VERY BREEZY WEST WINDS ON THURSDAY. GUSTS TO 40MPH
ACROSS THE KEWEENAW AND WESTERN SHORE ARE NOT OUT OF THE QUESTION.
FRIDAY THROUGH SUNDAY...WEAK MID-LEVEL CYCLONIC FLOW WILL CONTINUE
OVER THE CWA ON FRIDAY...RESULTING IN VERY SMALL CHANCES OF RAIN
WITH ANY SUBTLE EMBEDDED SHORTWAVE. WILL MAINTAIN A DRY FORECAST
GIVEN THE LITTLE CHANCE OF ANYTHING MATERIALIZING. SATURDAY LOOKS TO
BE ANOTHER WARM DAY AS MID-LEVEL RIDGING AND INCREASING H8 TEMPS
BUILD ACROSS THE UPPER GREAT LAKES. TEMPS SHOULD REACH THE 80S FOR
MOST OF THE CWA. MID-LEVEL TROUGHING GLANCING THE NORTHERN HIGH
PLAINS EARLY SATURDAY WILL RESULT IN LOW-PRESSURE DEVELOPMENT ACROSS
THE NORTHERN PLAINS AND SOUTH-CENTRAL CANADA. GUIDANCE SHOWS SOME
DIFFERENCES IN THE TIMING OF AN ASSOCIATED COLD FRONT CROSSING THE
CWA...BUT A ROUND OF SHOWERS AND STORMS SHOULD AFFECT THE AREA
SOMETIME LATE SATURDAY NIGHT THROUGH SUNDAY. EITHER WAY...GUSTY
SOUTHERLY WINDS OVER 25MPH WILL LIKELY OCCUR AHEAD OF THIS FRONT
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 723 AM EDT MON AUG 17 2015
SINCE A COLD FRONT WILL STALL JUST TO THE SOUTH OF UPPER MICHIGAN
TODAY...AN UPPER DISTURBANCE TRACKING ALONG THIS BOUNDARY WILL
BRING A CONTINUED CHC OF MORE -SHRA INTO THE AFTERNOON AT SAW.
WITH A WSHFT TO AN UPSLOPE NNE DIRECTIN IN THE AFTN AND MORE
LINGERING MOISUTRE...MVFR CIGS ARE LIKELY AT SAW FOR A TIME.
EXPECT ENOUGH LINGERING LOW LEVEL MOISTURE FOR SOME MVFR FOG TO
ALSO DEVELOP. SINCE CMX AND IWD WILL BE FARTHER FROM THE FRONT AND
DEEPER INTO THE INCOMING DRY AIRMASS...VFR CONDITIONS WILL REMAIN
THE RULE THERE
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EDT MON AUG 17 2015
WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH TONIGHT...THEN
NE WINDS WILL INCREASE TO UP TO 30 KNOTS TUE INTO TUE NIGHT AS A LOW
PRES SYSTEM MOVES INTO THE UPPER MS VALLEY. WINDS MAY TEMPORARILY
DIMINISH WED AS A LOW PRES SYSTEM MOVES TOWARD LAKE SUPERIOR.
HOWEVER...AS THE STRONG LOW DEPARS LATE WED NIGHT INTO THU SOME WRLY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LS...NONE.
LM...NONE.
&&
$$
UPDATE...JSL
SHORT TERM...JLB
LONG TERM...TK
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
723 AM EDT MON AUG 17 2015
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN UPPPER
MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN AND UPPER
LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET OVER NW
ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER MI. THE
AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG LINGERED OVER
THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO NEAR 40 KNOTS
SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN CWA OVERNIGHT
NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCPAE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAI WITH MAX TEMPS IN THE
LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW TO THE
LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT MON AUG 17 2015
SEASONABLY COOL WEATHER WILL PREVAIL FOR THE MIDDLE OF THE WEEK
AMIDST RAIN. TEMPS WILL INCH BACK TO ABOVE AVERAGE BY SATURDAY
BEFORE A COLD FRONT BRINGS A CHANCE FOR RAIN AND ANOTHER COOL-DOWN
ON SUNDAY.
TUESDAY...DEEP MID-LEVEL TROUGHING WILL BE ONGOING ACROSS THE
NORTHERN AND CENTRAL PLAINS BY TUESDAY MORNING...WITH A LEE CYCLONE
FORMING OVER THE CENTRAL HIGH PLAINS. MEANWHILE...THE COLD FRONT
THAT CROSSED THE AREA EARLIER TODAY WILL HAVE WASHED OUT ACROSS
NORTHERN WI...WITH THE H7 TO H8 FRONT LINGERING AS FAR NORTH AS THE
SOUTH-CENTRAL CWA. WIDESPREAD WAA AHEAD OF THE DEVELOPING LOW LOOKS
TO HOLD OFF UNTIL TUESDAY NIGHT...THOUGH MID-LEVEL FGEN BECOMES
APPARENT BY THE AFTERNOON. WITH MODELS BEGINNING TO BACK OFF ON THE
SOUTHWARD PUSH OF DEEP DRY AIR BEHIND THE FRONT TODAY...THINK THAT
AT LEAST SOME LIGHT RAIN WILL BE POSSIBLE BY TUESDAY AFTERNOON.
GIVEN THAT WAA/ISENTROPIC LIFT IS STILL MINIMAL...CONTINUED WITH
JUST SLIGHT CHANCES IN THE FORECAST.
TUESDAY NIGHT AND WEDNESDAY...LOW-LEVEL MOISTURE TRANSPORT AND
ISENTROPIC LIFT QUICKLY INCREASE TUESDAY EVENING AS THE SFC LOW
STRENGTHENS AND NEARS. THE MID-LEVEL SHORTWAVE BEGINS TO TAKE ON
MORE OF A NEGATIVE TILT BY THIS TIME...SENDING MUCH OF THE MID-LEVEL
Q-VECTOR CONV NNE ACROSS MN AND WESTERN LAKE SUPERIOR.
ADDITIONALLY...THE LEFT-EXIT OF A STRENGTHENING 110KT UPPER JET
STREAK WILL PASS WEST OF THE CWA. WITH PWATS SURPASSING 1.5 IN...A
BAND OF HEAVY RAIN SHOULD DEVELOP WEST OF THE CWA...POSSIBLY
CLIPPING THE FAR WEST. MEANWHILE...STEADY LIGHT TO MODERATE RAIN
ASSOCIATED WITH THE WAA IS EXPECTED FOR THE REMAINDER OF THE CWA
THROUGH THE NIGHT. DYNAMICS ARE FAVORABLE FOR POSSIBLE THUNDER
ACROSS THE WEST...WHILE MUCAPE OF AROUND 500 J/KG WILL BE ENOUGH FOR
SOME EMBEDDED THUNDER ACROSS THE EAST.
A RATHER PRONOUNCED MID-LEVEL DRY SLOT WILL QUICKLY SPREAD ACROSS
THE CWA FROM THE SW WEDNESDAY MORNING AS THE SFC LOW TRACKS NNE
ACROSS WESTERN LAKE SUPERIOR. STEEPENING MID-LEVEL LAPSE RATES AHEAD
OF THIS DRY SLOT WILL ALLOW FOR SOME EMBEDDED THUNDERSTORMS. SHOWERS
BECOME ISOLATED ACROSS THE CENTRAL UNDER THE DRY SLOT...BUT CONTINUE
FOR THE FAR WEST AND EAST DURING THE AFTERNOON. ALSO...S TO SW WINDS
LOOK TO GET QUITE GUSTY ACROSS THE CENTRAL AND EAST AHEAD OF AND
UNDER THE DRY SLOT.
WEDNESDAY NIGHT AND THURSDAY...WRAP AROUND MOISTURE WILL KEEP RAIN
CHANCES ACROSS MOST OF THE CWA...PARTICULARLY ALONG LAKE THE WEST
WIND BELTS OF LAKE SUPERIOR...THROUGH THURSDAY BEFORE SYNOPTIC
FORCING AND MOISTURE DEPART THURSDAY NIGHT. H8 TEMPS DOWN TO 5C
COMBINED WITH A STRONG GRADIENT FLOW AND RELATIVELY WARM LAKE TEMPS
WILL ALLOW FOR VERY BREEZY WEST WINDS ON THURSDAY. GUSTS TO 40MPH
ACROSS THE KEWEENAW AND WESTERN SHORE ARE NOT OUT OF THE QUESTION.
FRIDAY THROUGH SUNDAY...WEAK MID-LEVEL CYCLONIC FLOW WILL CONTINUE
OVER THE CWA ON FRIDAY...RESULTING IN VERY SMALL CHANCES OF RAIN
WITH ANY SUBTLE EMBEDDED SHORTWAVE. WILL MAINTAIN A DRY FORECAST
GIVEN THE LITTLE CHANCE OF ANYTHING MATERIALIZING. SATURDAY LOOKS TO
BE ANOTHER WARM DAY AS MID-LEVEL RIDGING AND INCREASING H8 TEMPS
BUILD ACROSS THE UPPER GREAT LAKES. TEMPS SHOULD REACH THE 80S FOR
MOST OF THE CWA. MID-LEVEL TROUGHING GLANCING THE NORTHERN HIGH
PLAINS EARLY SATURDAY WILL RESULT IN LOW-PRESSURE DEVELOPMENT ACROSS
THE NORTHERN PLAINS AND SOUTH-CENTRAL CANADA. GUIDANCE SHOWS SOME
DIFFERENCES IN THE TIMING OF AN ASSOCIATED COLD FRONT CROSSING THE
CWA...BUT A ROUND OF SHOWERS AND STORMS SHOULD AFFECT THE AREA
SOMETIME LATE SATURDAY NIGHT THROUGH SUNDAY. EITHER WAY...GUSTY
SOUTHERLY WINDS OVER 25MPH WILL LIKELY OCCUR AHEAD OF THIS FRONT
SATURDAY INTO SUNDAY MORNING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 723 AM EDT MON AUG 17 2015
SINCE A COLD FRONT WILL STALL JUST TO THE SOUTH OF UPPER MICHIGAN
TODAY...AN UPPER DISTURBANCE TRACKING ALONG THIS BOUNDAY WILL BRING
A CONTINUED CHC OF MORE -SHRA INTO THE AFTERNOON AT SAW. WITH A
WSHFT TO AN UPSLOPE NNE DIRECTIN IN THE AFTN AND MORE LINGERING
MOISUTRE...MVFR CIGS ARE LIKELY AT SAW FOR A TIME. EXPECT ENOUGH
LINGERING LOW LEVEL MOISTURE FOR SOME MVFR FOG TO ALSO DEVELOP.
SINCE CMX AND IWD WILL BE FARTHER FROM THE FRONT AND DEEPER INTO THE
INCOMING DRY AIRMASS...VFR CONDITIONS WILL REMAIN THE RULE THERE
THROUGH THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EDT MON AUG 17 2015
WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH TONIGHT...THEN
NE WINDS WILL INCREASE TO UP TO 30 KNOTS TUE INTO TUE NIGHT AS A LOW
PRES SYSTEM MOVES INTO THE UPPER MS VALLEY. WINDS MAY TEMPORARILY
DIMINISH WED AS A LOW PRES SYSTEM MOVES TOWARD LAKE SUPERIOR.
HOWEVER...AS THE STRONG LOW DEPARS LATE WED NIGHT INTO THU SOME WRLY
GALE FORCE GUSTS TO 35 KNOTS ARE POSSIBLE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...TK
AVIATION...JLB
MARINE...JLB
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
633 AM EDT MON AUG 17 2015
.SYNOPSIS...
MOISTURE INCREASES MONDAY THROUGH WEDNESDAY. COLD FRONT THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
UPDATE...
NO CHANGES THIS MORNING.
PREVIOUS DISCUSSION...
WATER VAPOR IMAGERY SHOWING THE DRAW OF DEEPER MOISTURE INTO THE
CWA IN RESPONSE TO AN UPPER LEVEL LOW PRESSURE SYSTEM LOCATED OVER
THE CONFLUENCE OF THE OHIO AND MISSISSIPPI RIVERS. NAM CONTINUES TO
MAINTAIN AN AGGRESSIVE NATURE WITH THE RESULTANT CONVECTIVE CHANCES
TODAY WHILE THE HRRR AND RAP ARE FAR LESS SO. FEEL MORE COMFORTABLE
WITH THESE TAMER MODELS...AND WILL BE INTERESTED TO SEE THEIR
SOLUTIONS FOR THE ACTIVITY TONIGHT. PUTTING A LOT OF STOCK INTO THE
UPPER LEVEL LOW MOVING THROUGH THE AREA WITH LIKELY POPS...AGAIN
MUCH MORE AGGRESSIVE IN THE NAM SOLUTION.
MAV HAS BEEN THE HOT GUIDANCE OF CHOICE LATELY...SO LEAN ON THIS
HEAVILY FOR THE AFTERNOON HIGHS TODAY. LIKE HOW IT KEEPS SOME OF THE
SOUTHERN ZONES SLIGHTLY COOLER THAN THE NORTH GIVEN THE ARRIVAL OF
CLOUDS EARLIER IN THE DAY AND THE BETTER CHANCES FOR CONVECTION.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
MODELS SHOW A SERIES OF UPPER DISTURBANCES MOVING THROUGH A DEEPER
MOIST SOUTHWEST FLOW TUESDAY AND WEDNESDAY...BEFORE A COLD FRONT
MOVES THROUGH ON THURSDAY TO BRING IN DRIER AND COOLER AIR FOR THE
REMAINDER OF THE WORK WEEK. MODELS HINT AT ONE DISTURBANCE MOVING
ACROSS EARLIER ON TUESDAY...ANOTHER ONE TUESDAY NIGHT AND EARLY
WEDNESDAY...BEFORE THE COLD FRONT MOVES ACROSS ON THURSDAY. DESPITE
THE LACK OF A LOW LEVEL FOCUS BEFORE THE COLD FRONT...THE
DISTURBANCES COMBINING WITH PW`S AOA 1.5 INCHES SUGGESTS HIGH POPS
FOR SHOWERS AND THUNDERSTORMS. WILL...FOCUS HIGHER POPS ON THE TWO
AFOREMENTIONED DISTURBANCES...BUT OTHERWISE KEEP LOWER POPS IN THE
JUICY AIR IN PLACE. SUNSHINE SHOULD BE LIMITED AND SO HIGH TEMPS
WILL BE IN THE 80S. SHOWERS AN STORMS RAMP UP AGAIN WEDNESDAY NIGHT
AND EARLY THURSDAY ALONG AND AHEAD OF THE COLD FRONT...DECREASING
FROM NORTHWEST TO SOUTHEAST DURING THURSDAY AS DRIER AND SOMEWHAT
COOLER AIR MOVES IN. HIGH PRESSURE WILL SETTLE IN FOR THURSDAY NIGHT
AND FRIDAY...WITH MOSTLY DRY WEATHER AND HIGH TEMPS AROUND 80
DEGREES FRIDAY...BUT WILL LEAVE JUST A LOW POP IN THE SOUTH AS
MODELS INDICATE SOME LINGERING MOISTURE DOWN THERE.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
A COLD FRONT PASSES ON THURSDAY. THERE IS STILL NOT GREAT MODEL
CONSENSUS...WITH THE EURO GIVING THE STRONGEST SOLUTION. FOR THE
MOST PART THE MAJOR DYNAMICS WILL BE NORTH OF THE FORECAST AREA.
HAVE INCREASED POPS WITH THE FRONT FROM WHAT WAS IN THE PREVIOUS
GRIDS. HAVE EVEN INCLUDED LIKELY OVER THE MOUNTAINS. NOT SURE HOW
QUICKLY IT WILL DRY OUT AS THE FRONT MIGHT GET HUNG UP. AT THIS
TIME WENT WITH THE PREVIOUS SCENARIO AND DRIED POPS OUT STARTING
FRIDAY.
&&
.AVIATION /10Z MONDAY THROUGH FRIDAY/...
CIRRUS CLOUDS WILL BE ON THE INCREASE THROUGH THE DAY...WITH
CUMULUS FORMATION AS WELL WITH AN APPROACHING UPPER LEVEL TROUGH.
SHOWERS AND THUNDERSTORMS WILL BE SLOW TO AFFECT THE
TERMINALS...WITH BETTER CHANCES AFTER THE 00Z TUESDAY TIME FRAME.
THESE CHANCES WILL CARRY OVER INTO THE OVERNIGHT AND WILL NOT BE
RELEGATED TO THE DAYTIME HEATING HOURS...THANKS TO THE
AFOREMENTIONED UPPER LEVEL FEATURE.
NO FOG TONIGHT DUE TO CLOUDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: MAY NEED MORE VCTS/TSRA TODAY AT BKW AND HTS.
TIMING TONIGHT IS IN QUESTION.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE MON 08/17/15
UTC 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20
EDT 1HRLY 05 06 07 08 09 10 11 12 13 14 15 16
CRW CONSISTENCY L L L M H H H H H H H H
HTS CONSISTENCY L L L M H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L L L H H H H H H H H
PKB CONSISTENCY L L L M H H H H H H H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 12Z TUESDAY...
IFR CONDITIONS POSSIBLE IN AREAS OF SHOWERS AND THUNDERSTORMS WITH
THE COLD FRONT ON THURSDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...JMV/26
NEAR TERM...26
SHORT TERM...JMV
LONG TERM...FB
AVIATION...26
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1103 AM CDT MON AUG 17 2015
.UPDATE...
AREA OF SHOWERS CURRENTLY EXTEND FROM NORTHEAST INTO SOUTHWEST
WISCONSIN...THEN TO THE WEST. THE SHOWERS WERE LOCATED BEHIND THE
SURFACE COLD FRONT...BEING FED BY UPPER DIVERGENCE FROM RIGHT REAR
ENTRANCE REGION OF 250 MB JET STREAK. THERE WAS ALSO SOME 700 MB
MOISTURE AND CYCLONIC VORTICITY ADVECTION IN THIS AREA.
THE UPPER DIVERGENCE IS EXPECTED TO SHIFT EASTWARD ACROSS THE AREA
THIS AFTERNOON...AS WELL AS THE SURFACE COLD FRONT. THERE IS NOT A
LOT OF LOW LEVEL FRONTOGENESIS RESPONSE ASSOCIATED WITH THE COLD
FRONT ITSELF. STILL LOOKS TO BE ENOUGH UPWARD VERTICAL MOTION TO
COMBINE WITH NO CAPPING TO HELP SOME SHOWERS AND THUNDERSTORMS
DEVELOP BY MIDDLE AFTERNOON AND SPREAD EAST INTO THE MIDDLE
EVENING HOURS. THIS IS SUPPORTED BY SEVERAL MESOSCALE MODELS.
AREA FORECAST SOUNDINGS ARE SHOWING WEAK DEEP LAYER SHEAR AND
WEAK TO MODEST AMOUNTS OF MEAN LAYER CAPE DURING THIS TIME...SO NO
SEVERE WEATHER IS EXPECTED. WILL KEEP LIKELY POPS GOING FOR THIS
AFTERNOON INTO THE MIDDLE EVENING HOURS. HIGH TEMPERATURES WILL BE
RAISED A FEW DEGREES IN THE CENTRAL AND EASTERN AREAS...GIVEN
CURRENT TRENDS.
&&
.AVIATION/18Z TAFS/...
A WEAK COLD FRONT WILL SHIFT SOUTHEAST INTO THE AREA THIS
AFTERNOON AND STALL AROUND OR JUST SOUTH OF THE AREA TONIGHT. AN
AREA OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP AND
MOVE EASTWARD WITH THE FRONT ACROSS THE AREA THIS AFTERNOON INTO
THE MIDDLE EVENING HOURS.
MAY SEE MVFR VISIBILITIES WITH ANY STORMS...ALONG WITH BRIEF
GUSTY WINDS. VFR CONDITIONS ARE EXPECTED OTHERWISE. WILL CONTINUE
WITH VICINITY AND TEMPO WORDING IN TAFS...GIVEN SOME UNCERTAINTY
WITH TIMING AND AREAL COVERAGE OF THE SHOWERS/STORMS.
ENOUGH LOW LEVEL MOISTURE AND LIGHT WINDS LATER TONIGHT INTO
TUESDAY MORNING SHOULD LEAD TO IFR FOG AND SOME LOW STRATUS
DEVELOPMENT ACROSS THE AREA. KEPT MENTION GOING IN TAFS.
FRONT MOVES BACK INTO THE AREA TUESDAY AS A WARM FRONT...WHICH
WILL BRING MORE CHANCES FOR SHOWERS AND STORMS. BEST CHANCES WILL
BE LATER IN THE DAY WITH DAYTIME HEATING. WILL MENTION VICINITY
THUNDER IN TAFS GIVEN SOME TIMING/AREAL COVERAGE UNCERTAINTY.
&&
.MARINE...
SOME SHOWERS/STORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND
LINGER INTO THE MIDDLE EVENING HOURS...AS A COLD FRONT SLIDES
SOUTHEAST INTO THE AREA.
SHOULD SEE FOG DEVELOP ACROSS THE NEARSHORE WATERS OF LAKE
MICHIGAN LATER TONIGHT INTO TUESDAY MORNING...WITH LIGHT WINDS AND
A MOIST AIRMASS OVER THE REGION. NOT EXPECTING WIDESPREAD DENSE
FOG AT THIS TIME...BUT PATCHY DENSE FOG IS POSSIBLE.
A TIGHT PRESSURE GRADIENT ON WEDNESDAY SHOULD LEAD TO WINDY
CONDITIONS ACROSS THE NEARSHORE WATERS. WINDS SHOULD BE OFFSHORE
DURING THIS TIME. GALE FORCE GUSTS MAY BE POSSIBLE WEDNESDAY.
&&
.PREV DISCUSSION... /ISSUED 343 AM CDT MON AUG 17 2015/
SHORT TERM...
TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM.
THE MAIN FOCUS INTO TONIGHT IS ON A COLD FRONT THAT STALLS OUT OVER
THE REGION AND WHEN/IF WE WILL GET RAIN SHOWERS/CONVECTION AHEAD OF
IT.
CURRENTLY...THIS COLD FRONT EXTENDS FROM EASTERN LAKE SUPERIOR
SOUTHWEST INTO CENTRAL IOWA WHICH IS JUST UPSTREAM FROM AN ELONGATED
MID LEVEL SHORT WAVE TROUGH NOTED ON WATER VAPOR IR/RAP ANALYSIS.
RAIN SHOWERS/CONVECTION HAS DEVELOPED AHEAD OF THE FRONT...BUT SEEMS
TO BE GOING A TAD SLOWER THAN PREVIOUS GUIDANCE HAD SUGGESTED.
THUS...HAVE SLOWED DOWN THE EASTWARD PROGRESSION OF THE RAIN SHOWERS
THIS MORNING.
17.07Z RAP SOUNDINGS SHOW A SKINNY CAPE PROFILE FOR TODAY AHEAD OF
THE FRONT WITH LITTLE TO NO 0-6KM WIND SHEAR...SO AM NOT EXPECTING
ANY SEVERE WEATHER WITH CONVECTION TODAY. THE 17.00Z NAM SEEMS TO
BE OVERDONE WITH THE BAND OF HIGH INSTABILITY AND RESULTANT
CONVECTION THAT IT DEVELOPS INTO FAR SOUTHEASTERN WISCONSIN THIS
AFTERNOON. WHILE IT DOES LOOK LIKE WE WILL SEE SOME WARMING THIS
MORNING IN THE WARM SECTOR...THE NAM BRINGS SURFACE DEW POINTS UP
INTO THE MID 70S IN THIS BAND WHERE MID TO UPPER 60S WILL BE MORE
LIKELY. THE COLD FRONT SHOULD FEATURE SOME RAIN SHOWERS/STORMS AS
IT COMES THROUGH THIS AFTERNOON/EVENING ALONG WITH THE MID LEVEL
SHORT WAVE TROUGH...IT IS JUST HOW MUCH WILL WE SEE. ACTIVITY
SHOULD LESSEN TONIGHT AS THE BETTER FORCING SHIFTS OFF TO THE EAST
AND THE SURFACE FRONT STALLS.
LONG TERM...
TUESDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE MEDIUM.
AN AMPLIFIED UPPER TROUGH DIGGING INTO THE CENTER OF THE COUNTRY
WILL BRING A POTENT SURFACE LOW TO THE MIDWEST TUESDAY NIGHT THROUGH
WEDNESDAY. THE 850MB BAROCLINIC ZONE WILL BE STALLED IN SOUTHERN WI.
UPPER DIVERGENCE FROM THE RIGHT ENTRANCE REGION OF THE UPPER JET
WILL LINGER OVER SOUTHERN WI ALL DAY TUESDAY. THE NOSE OF THE LOW
LEVEL JET SHOULD BRIEFLY POINT INTO SOUTHERN WI LATE TUESDAY
AFTERNOON/EARLY EVENING... SO THIS WILL BE OUR BEST CHANCE FOR
SHOWERS AND THUNDERSTORMS.
THIS IS A PARTICULARLY STRONG SYSTEM FOR THIS TIME OF YEAR.
HOWEVER... WEAK MID LEVEL LAPSE RATES WILL KEEP CAPE/INSTABILITY ON
THE LOW SIDE... BUT SHEAR WILL BE MODERATE TO STRONG ESPECIALLY IN
THE LOW LEVELS. THIS SYSTEM HAS THE POTENTIAL FOR ISOLATED SEVERE
WEATHER SO SPC HAS THE MKX AREA IN A MARGINAL RISK WITH A SLIGHT
RISK IN THE FAR SOUTHWEST COUNTY WARNING AREA.
EXPECT THE DRY SLOT/COLD FRONT TO MOVE ACROSS SOUTHERN WI EARLY
WEDNESDAY MORNING. WESTERLY WINDS ON WEDNESDAY WILL BE GUSTY...
ALTHOUGH THERE IS MODEL UNCERTAINTY FOR HOW HIGH THE WINDS WILL BE.
THURSDAY THROUGH FRIDAY... FORECAST CONFIDENCE MEDIUM.
THE UPPER LOW WILL TAKE ITS TIME EXITING THE GREAT LAKES REGION. A
HIGH PRESSURE RIDGE WILL SPREAD IN THU NIGHT. MODELS ARE SHOWING
WISCONSIN DRY WITH MOSTLY CLEAR SKIES FOR THIS PERIOD.
SATURDAY THROUGH MONDAY... FORECAST CONFIDENCE MEDIUM.
A LOW PRESSURE TROUGH WILL CROSS THE UPPER MIDWEST/SOUTHERN CANADA
OVER THE WEEKEND. THE TRAILING COLD FRONT WILL BRING A CHANCE FOR
SHOWERS AND THUNDERSTORMS TO WISCONSIN SATURDAY NIGHT INTO SUNDAY.
AVIATION/12Z TAFS/...
SOME GUSTY CONDITIONS OF UP TO 20KT ARE POSSIBLE THIS
MORNING/AFTERNOON AHEAD OF A COLD FRONT WHICH WILL STALL OUT ACROSS
THE REGION TONIGHT. RAIN SHOWERS AND THUNDERSTORMS ARE LIKELY THIS
AFTERNOON INTO THIS EVENING WITH SOME BRIEF DROPS IN VISIBILITY
POSSIBLE WITH THEM. IF RAIN DOES FALL TODAY...THERE COULD BE SOME
FOG THAT DEVELOPS TONIGHT WITH WINDS GOING LIGHT ALONG THE STALLING
OUT COLD FRONT...BUT SKIES SHOULD BE CLOUDY WHICH MAY LIMIT HOW MUCH
RADIATIONAL COOLING OCCURS.
MARINE...
WINDS WILL SHIFT FROM THE SOUTHWEST TO THE NORTH BEFORE BECOMING
LIGHT AND VARIABLE TONIGHT AS A COLD FRONT MOVES DOWN INTO THE
REGION AND STALLS OUT. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE
AHEAD OF THE FRONT WITH SOME GUSTY WINDS ACCOMPANYING A FEW OF THE
THUNDERSTORMS. WINDY CONDITIONS ARE EXPECTED ON WEDNESDAY AS A LOW
PRESSURE SYSTEM MOVES THROUGH THE REGION.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...WOOD
TODAY/TONIGHT AND AVIATION/MARINE...HALBACH
TUESDAY THROUGH SUNDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
659 AM CDT MON AUG 17 2015
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
THE COLD FRONT EXTENDED FROM NORTH CENTRAL WISCONSIN INTO
NORTHERN KANSAS EARLY THIS MORNING. REGIONAL RADARS INDICATE THE
REMAINING SHOWERS HAVE BECOME ORIENTED ALONG AND JUST BEHIND THE
FRONT WITH THE LARGEST CONCENTRATION MOVING SLOWLY NORTHEAST OUT
OF NORTHERN IOWA. THIS AREA OF SHOWERS IS ASSOCIATED WITH A WEAK
SECONDARY MOISTURE TRANSPORT AXIS THAT THE 17.06Z RAP MOVES
NORTHEAST INTO THE AREA AND THEN STARTS TO WEAKEN IT AROUND 12Z
INTO THE REST OF THE MORNING. THE 17.06Z HRRR SHOWS THESE TRENDS
WELL AND BRINGS IN THE BAND OF RAIN THROUGH ABOUT 12Z AND THEN
SHOWS IT WEAKENING AS THE MORNING PROGRESSES WITH THE WEAKENING
MOISTURE TRANSPORT.
THE FRONT WILL CONTINUE TO WORK SLOWLY SOUTH THROUGH THE REST OF
THE DAY BUT SOME UNCERTAINTY ON JUST HOW MUCH ACTIVITY WILL OCCUR
WITH IT. MOST OF THE HI-RES MESO MODELS SHOW A CONTINUED
DIMINISHING TREND INTO THE EARLY AFTERNOON WITH MAINLY SCATTERED
COVERAGE. WITH NO SHORT WAVE TROUGHS TO PROVIDE ANY DYNAMIC
SUPPORT TODAY...ANY INCREASE IN ACTIVITY WILL HAVE TO BE
THERMODYNAMICALLY DRIVEN. WITH SOME HEATING OCCURRING UNDER THE
CLOUD COVER...THE 17.00Z NAM SUGGESTS THE MU CAPE COULD INCREASE
INTO THE 1000-1500 J/KG RANGE ACROSS THE SOUTH DURING THE
AFTERNOON. THE FRONTOGENESIS IN THE 1000-850 MB LAYER ALSO SHOWS A
DIURNAL INCREASE DURING THE AFTERNOON AND THIS MAY BE ENOUGH TO
MAINTAIN SOME SCATTERED ACTIVITY ALONG THE FRONT.
DIFFERENCES AMONG THE MODELS THEN START TO SHOW UP IN HOW FAR
SOUTH THE FRONT PROGRESSES TONIGHT. THE NAM AND THE MESO MODELS
SUGGEST A GENERAL LULL IN THE ACTIVITY THIS EVENING BUT THEN START
TO BRING THE FRONT BACK LATE TONIGHT AHEAD OF THE NEXT SYSTEM.
WATER VAPOR SATELLITE THIS MORNING SHOWS THIS NEXT SHORT WAVE
TROUGH WAS OVER EASTERN WASHINGTON AND OREGON. THE GENERAL TREND
IN THE MODELS WITH THIS SYSTEM REMAINS THE SAME WITH IT
INTENSIFYING AS IT APPROACHES...FORMING A CLOSED UPPER LEVEL LOW
OVER THE EASTERN DAKOTAS TUESDAY. SOME DIFFERENCES ON HOW STRONG
THE WAVE BECOMES WITH THE 17.00Z GFS CONTINUING ITS TREND OF BEING
THE STRONGEST WITH IT AND ALSO THEN THE SLOWEST TO MOVE IT OUT.
THE UPPER LEVEL LOW AND SHORT WAVE TROUGH SHOULD THEN LIFT
NORTHEAST ACROSS MINNESOTA AND INTO CANADA TUESDAY NIGHT INTO
WEDNESDAY. THE FORCING AHEAD OF THIS WAVE WILL START TO INCREASE
LATE TONIGHT AS HEIGHT FALLS START TO SPREAD OVER THE REGION. THE
FORCING LOOKS TO BE THE STRONGEST TUESDAY NIGHT AS MODERATE PV
ADVECTION IN THE 500-300 MB LAYER MOVES ACROSS WITH THE SHORT WAVE
TROUGH. THE BEST MOISTURE TRANSPORT SHOULD STAY TO THE WEST OF THE
AREA TONIGHT BUT THERE IS SOME SUGGESTION OF A WEAK BRANCH COMING
INTO THE FRONT FOR LATE TONIGHT. THIS MOISTURE TRANSPORT THEN
CONTINUES TO INCREASE THROUGH THE DAY TUESDAY AND LOOKS TO BE
RIGHT INTO THE AREA FOR TUESDAY EVENING. BASED ON THESE SIGNALS
PLAN TO START INCREASING THE RAIN CHANCES LATE TONIGHT ACROSS THE
SOUTH WITH THE CHANCES THEN INCREASING ACROSS THE ENTIRE AREA
TUESDAY. THE HIGHEST RAIN CHANCES SHOULD OCCUR TUESDAY EVENING AS
THE FRONT MOVES BACK INTO THE AREA AS A SURFACE LOW TRACKS FROM
IOWA INTO MINNESOTA. THEN EXPECTING THE DRY SLOT TO START WORKING
IN FROM THE SOUTH FOR LATE TUESDAY NIGHT INTO WEDNESDAY AS THE
ENTIRE SYSTEM LIFTS OFF TO THE NORTH.
QUESTIONS ON JUST HOW MUCH OF A SEVERE THREAT THERE WILL BE WITH
THIS SYSTEM. EXPECTING RAIN TO BE FALLING AHEAD OF THE WARM FRONT
AND THE WARM SECTOR ITSELF TO NOT BE VERY CLEAN. THIS SHOULD LIMIT
THE AMOUNT OF INSTABILITY WITH BOTH THE NAM AND GFS SHOWING LESS
THEN 750 J/KG OF ML CAPE AVAILABLE IN THE WARM SECTOR. WITH THE
GFS BEING THE STRONGEST WITH THE SYSTEM IT PRODUCES THE MOST SHEAR
WITH 30 TO 35 KNOTS IN THE 0-3KM LAYER WHILE THE NAM STRUGGLES TO
GET 20 KNOTS IN HERE IN THE SAME LAYER. COULD SEE SOME STRONGER
STORMS DEVELOP BUT STILL NOT THINKING THERE WOULD BE MUCH IN THE
WAY OF AN ORGANZID SEVERE EVENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
ANY LINGERING RAIN CHANCES FROM THIS SYSTEM SHOULD MAINLY BE
LIMITED TO THE INTERSTATE 94 CORRIDOR FOR WEDNESDAY NIGHT BEFORE
DRY WEATHER SETTLES IN FOR THURSDAY THROUGH FRIDAY. THE RAIN
CHANCES THEN LOOK LIKE THEY WILL RETURN FOR THE UPCOMING WEEKEND.
PRETTY GOOD AGREEMENT BETWEEN THE GFS AND 17.00Z ECMWF OF A COLD
FRONT SWEEPING ACROSS THE REGION SATURDAY AND SATURDAY NIGHT. THE
SHORT WAVE TROUGH WITH THIS SYSTEM LOOKS TO BE PRETTY SIMILAR TO
THE UPCOMING SYSTEM FOR TUESDAY. IT SHOULD COME IN OFF THE
NORTHERN PACIFIC AND INTENSIFY ONCE IT CROSSES THE NORTHERN
ROCKIES BUT IT MAY TRACK SLIGHTLY FARTHER TO THE NORTH ACROSS
NORTH DAKOTA OR EXTREME SOUTHERN CANADA. THIS COULD BRING IN A
DECENT ROUND OF SHOWERS AND STORMS AGAIN AS THE FRONT COMES
ACROSS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 659 AM CDT MON AUG 17 2015
SHOWERS AND ISOLATED THUNDERSTORMS WILL EDGE SOUTHEAST ACROSS THE
AREA THIS MORNING ALONG A WEAKENING COLD FRONT WITH PERIODS OF
MVFR TO IFR CONDITIONS POSSIBLE AT TIMES. THIS ACTIVITY WILL
GRADUALLY TAPER OFF AND SHIFT SOUTHEAST OF KRST BY LATE THIS
MORNING AND BY MID TO LATE AFTERNOON AT KLSE. CEILINGS COULD FALL
TO AROUND 400 FT UNDER THE HEAVIER SHOWERS AND THE VISIBILITY MAY
BE REDUCED TO 2 SM OR LESS. IN THE WAKE OF THE FRONT A BRIEF
PERIOD OF MVFR STRATUS IS EXPECTED THEN CEILINGS SHOULD IMPROVE TO
VFR AND STAY THERE THROUGH THE OVERNIGHT HOURS.
&&
.HYDROLOGY...
ISSUED AT 348 AM CDT MON AUG 17 2015
DECENT RAINFALL AMOUNTS ARE EXPECTED WITH THE UPCOMING SYSTEM FROM
LATE TONIGHT THROUGH WEDNESDAY. CURRENTLY EXPECTING RAINFALL
AMOUNTS OF 1 TO 1.5 INCHES OVER THIS SPREAD OUT PERIOD. THESE
AMOUNTS AND THE SOMEWHAT EXTENDED TIME FRAME OVER WHICH THEY ARE
EXPECTED...SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING
PROBLEMS...ESPECIALLY GIVEN THE RECENT DRY CONDITIONS THAT HAVE
DEVELOPED. NOT ANTICIPATING THE NEED FOR ANY HYDROLOGIC HEADLINES
FROM THIS SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
402 PM MDT MON AUG 17 2015
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 327 PM MDT MON AUG 17 2015
.SHORT TERM...(TONIGHT THROUGH TUESDAY NIGHT)
ISSUED AT 136 PM MDT MON AUG 17 2015
COMBINATION OF JET MAXIMA ALOFT AND CONDITIONALLY UNSTABLE
ENVIRONMENT HAS GENERATED SCATTERED STORMS THIS AFTERNOON...PRIMARILY
SOUTH OF US HIGHWAY 40. GIVEN THE SHEAR ENVIRONMENT...SOME CELLS
WILL BE STRONG WITH GUSTY WINDS AND SMALL HAIL. STORM PREDICTION
CENTER PLACED THE ERN FRINGE OF OUR FORECAST AREA IN THE MARGINAL
CATEGORY. CURRENT TRENDS OFFERED BY RADAR AND 1 MIN SATELLITE
IMAGES (FORTUNATE THAT IT EXTENDS OVER THE WESTERN SLOPE TODAY)
SHOW STRENGTHENING STORMS NEAR THE I70 CORRIDOR. WEATHER SPOTTER
BETWEEN GLENWOOD SPRINGS AND CARBONDALE REPORTED ONE HALF INCH
SIZED HAIL. WITH UPSTREAM TROUGH OVER THE NRN ROCKIES APPROACHING
THE CENTRAL ROCKIES...NOT UNREASONABLE THAT STRONGER STORMS
(PERHAPS A SEVERE STORM OR TWO) MAY FORM LATE THIS AFTERNOON. BY
NIGHTFALL...STORMS SHOULD BE DIMINISHING. EXCEPT TRAILING ENERGY
OVER SOUTHWEST COLORADO MAY KEEP THINGS ACTIVE OVER LA PLATA AND
ARCHULETA COUNTY UNTIL MIDNIGHT OR SO.
NORTHEAST UTAH/EXTREME NW COLORADO...DEEP MIXED LAYER ASSOCIATED
WITH THE SURFACE TROUGH RESULTS IN RAPID DRYING. STORMS WILL NOT
BE FAVORED IN THIS REGION AS THE MOIST ENVIRONMENT GETS PUSHED
EASTWARD BY UPSTREAM TROUGH.
TUESDAY AND TUESDAY NIGHT...
COOLER AND MUCH DRIER AIR UNDER NW FLOW OVER THE AREA TUESDAY AND
TUESDAY NIGHT SHOULD RESULT IN MAX TEMPERATURES 5-10 DEGREES F
LOWER THAN TODAY...WITH GREATEST COOLING IN NORTHERN AND CENTRAL
ZONES. ALL MODELS SHOW H7 TEMPERATURES DROPPING 4 TO 8 DEGREES C
LOWER THAN TODAY. MIN TEMPERATURES TUESDAY NIGHT COULD DROP INTO
THE UPPER 30S IN SOME OF THE COLDER HIGH ELEVATION VALLEYS SUCH AS
IN THE GUNNISON AREA. MOSTLY CLEAR SKIES EXPECTED OVER THE AREA...
WITH SOME CLOUD BUILDUPS IN THE AFTERNOON AND EARLY EVENING OVER
THE MOUNTAINS AND ONLY ISOLATED THUNDERSTORMS MAINLY NEAR THE
CONTINENTAL DIVIDE AROUND PEAK HEATING TIME.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 327 PM MDT MON AUG 17 2015
WEDNESDAY THROUGH THURSDAY NIGHT...
DRY NORTHWEST FLOW CONTINUING WEDNESDAY THROUGH THURSDAY NIGHT
...WITH MOSTLY CLEAR SKIES EXPECTED TO PERSIST. MODELS DROPPING
H7 TEMPERATURES ANOTHER COUPLE DEGREES C ON WEDNESDAY WITH MAX
TEMPERATURES GENERALLY 3 DEGREES F LOWER THAN TUESDAY. THEN AS
UPPER TROUGH/LOW TRAVERSING NORTHERN STATES SHIFTS EASTWARD ON
THURSDAY...EXPECT SOME AIRMASS WARMING WITH MAX TEMPERATURES
SEVERAL DEGREES WARMER THURSDAY THAN ON WEDNESDAY.
FRIDAY THROUGH MONDAY...
MODELS INDICATE ANOTHER UPPER TROUGH BRUSHING OUR CWA BEGINNING
FRIDAY AND THEN MOVING TO THE EAST OF OUR AREA SATURDAY NIGHT.
EXPECT AN UPTICK OF MOISTURE INTO OUR AREA DURING THIS PERIOD
...THEN DECREASING SOME SUNDAY AND MONDAY UNDER A VERY WEAK
WESTERLY FLOW ALOFT WITH RESIDUAL MOISTURE UNDER THE INFLUENCE OF
DAYTIME HEATING. AFTER ANOTHER UNSEASONABLY WARM DAY ON FRIDAY...
NOTICEABLY COOLER AIR EXPECTED INTO OUR AREA AGAIN SATURDAY
THROUGH SUNDAY...BEFORE WARMER AIR RETURNS ON MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 327 PM MDT MON AUG 17 2015
SCATTERED -TSRA CONTINUE OVER THE CENTRAL ZONES SOUTH OF THE
/ROAN/FLAT TOP MOUNTAINS. KRIL KASE KEGE COULD SEE CIGS BLO 070
ALONG WITH SMALL HAIL AND ERRATIC WIND GUSTS OF 25-40KTS. AFT 03Z
STORMS BECOME ISOLATED IN COVERAGE WITH ALL STORMS ENDING BY 08Z.
VFR CONDITIONS CONTINUE THROUGH TUESDAY WITH ISOLATED AFTERNOON
-TSRA NEAR THE CONTINENTAL DIVIDE.
&&
.FIRE WEATHER...
ISSUED AT 1145 AM MDT MON AUG 17 2015
DEEP MIXED LAYER WILL RESULT THIS AFTERNOON AS LOWER SURFACE
PRESSURE OVER NW COLORADO DEEPENS. SUSTAINED WINDS OF 15-20 MPH
IS EXPECTED WITH PEAK GUSTS OF 35 MPH IN ADVANCE OF A COLD FRONT.
HIGHER RESOLUTION MODELS INDICATE THAT DEW POINT VALUES WILL DROP
QUICKLY WHEN THE SURFACE WINDS DEVELOP...THIS TREND MAY BE
VERIFYING AS THE KCAG (CRAIG) ASOS OBSERVED THE DEW POINT FALLING
FROM 48F TO 28F WITHIN TWO HOURS. THE HRRR MODEL SHOW VALUES
FALLING INTO THE 20S ACROSS MOFFAT COUNTY (FIRE WEATHER ZONE
200)...WHICH IS BELOW MOS GUIDANCE VALUES. SPLIT THE DIFFERENCE
BETWEEN THE HRRR AND GUIDANCE...THE NET RESULT IS HUMIDITY VALUES
OF 10-15% AFTER 20Z (2 PM). THE WINDS MAY PERSIST THROUGH THE
EARLY EVENING HOURS GIVEN TIGHTENING PRESSURE GRADIENTS. CRITICAL
FIRE WEATHER CONDITIONS MAY PERSIST UNTIL AFTER SUNSET.
&&
$$
SHORT TERM...PF/JRP
LONG TERM...JRP
AVIATION...JOE
FIRE WEATHER...PF
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1145 AM MDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1035 AM MDT MON AUG 17 2015
UPDATED TO INCLUDE SOME SHOWERS AND ISOLATED THUNDERSTORMS IN SOME
LOWER ELEVATION ZONES IN CENTRAL PORTION OF OUR CWA BEGINNING THIS
MORNING...WHICH DEVELOPED EARLIER IN THE DAY THAN PREVIOUSLY
EXPECTED. THIS CONVECTIVE ACTIVITY HAS DEVELOPED IN THE NORTHERN
BOUNDS OF UPPER LEVEL DIFLUENCE.
UPDATE ISSUED AT 750 AM MDT MON AUG 17 2015
SURFACE BOUNDARY THAT CUTS ACROSS THE SRN PORTION OF THE FORECAST
AREA HAS BEEN THE TRIGGER MECHANISM FOR ISOLATED SHOWERS AND
THUNDERSTORMS. THE HRRR MODEL SHOWS ACTIVITY EXPANDING ACROSS THIS
AREA AS THE DAY PROGRESSES...BUT A BIT SLOW HANDLING THE CURRENT
ACTIVITY.
THE OTHER CONCERN IS THE POTENTIAL FOR RED FLAG CONDITIONS ACROSS
NW COLORADO...SPECIFICALLY ZONE 200. RAP13 SHOWING DEEPENING SURFACE
LOW (SUB 1000 MB) FROM RAWLINS TRAILING BACK TO SOUTHEAST UTAH.
UPSTREAM...THERE IS THERMAL GRADIENT THAT SPREADS INTO NW COLORADO
THIS EVENING. THE HRRR MODEL SHOWS SURFACE WINDS 15-20 KTS ACROSS
NW COLORADO THIS AFTERNOON. WITH DEEP MIXED LAYER...EXPECT GUSTY
WINDS TO DEVELOP. FIRST IMPRESSION IS THAT RED FLAG CONDITIONS
WILL BE MET...AT LEAST FOR FIRE WEATHER ZONE 200 AND POSSIBLY 202.
PLAN TO TAKE ANOTHER LOOK AT THIS ONCE 12Z GUIDANCE ARRIVES BEFORE
MAKING A FINAL DECISION.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
DRIER AIR BEGINS TO WORK ACROSS NORTHEAST UTAH AND NORTHWEST
COLORADO THIS AFTERNOON AS A 85 KT UPPER LEVEL JET REMAINS OVERHEAD.
THE BEST MOISTURE IS ALONG THE BOOKCLIFFS AND SOUTH ACROSS SOUTHEAST
UTAH AND SOUTHWEST COLORADO WHERE PRECIPITABLE WATER (PW) VALUES
RANGE FROM 0.75 TO 1.0 INCH. EXPECTING STORMS TO DEVELOP OVER THE
HIGHER TERRAIN BY LATE MORNING/EARLY AFTERNOON ACROSS WEST CENTRAL
AND SOUTHWEST COLORADO WITH STORMS DRIFTING AND IMPACTING VALLEYS BY
MID AFTERNOON THROUGH EARLY EVENING GIVEN SOME DECENT STORM MOTION
FROM WEST TO EAST AT 20 MPH. THERE IS SOME DECENT INSTABILITY AND
SHEAR SO EXPECTING SOME ROTATING STORMS WITH GOOD SUSTAINING
UPDRAFTS SIMILAR TO SUNDAY`S ENVIRONMENT. MAINLY BRIEF HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS CAN BE EXPECTED WITH
FREQUENT LIGHTNING.
AN UPPER LEVEL LOW PRESSURE TROUGH WILL MOVE THROUGH MONTANA AND
NORTHEAST WYOMING THIS AFTERNOON AND EVENING WITH AN ASSOCIATED COLD
FRONT MOVING THROUGH THIS EVENING. THERE IS A NOTICEABLE WIND SHIFT
FROM WEST TO NORTHWEST AS WELL AS A DECREASE IN PW VALUES BEHIND
THIS FRONT TO 0.25 TO 0.5 INCH RANGE. THE SHORT TERM MODELS ARE IN
PRETTY GOOD AGREEMENT WITH TIMING OF THE FRONT WHICH SHOW THE
FRONT MOVING THROUGH THE AREA THIS EVENING INTO EARLY TUESDAY
MORNING. FOLLOWED NAM12 GUIDANCE FOR TIMING WHICH SHOWS THE FRONT
THROUGH NE UTAH AND NW COLORADO BETWEEN 6 PM AND 9 PM AND THROUGH
SE UTAH AND WEST CENTRAL COLORADO BETWEEN 9 PM AND MIDNIGHT. THE
FRONT WILL BE EXITING THE REST OF THE AREA BY 3 AM. THE MODELS ARE
NOT PERFECT SO THIS TIMING MAY NOT BE EXACT BUT AT THIS TIME...IT
GIVES A GOOD APPROXIMATION.
ANOTHER CONCERN IS THE POTENTIAL FOR FIRE WEATHER CRITERIA TO BE MET
ACROSS NORTHWEST COLORADO LATE THIS AFTERNOON AND EVENING WHERE
DRIER AIR WILL BE IN PLACE. THE TIMING OF THE COLD FRONT IS
CRITICAL FOR WHEN AND IF RED FLAG CRITERIA WILL BE MET...WHICH AT
THIS TIME SEEMS TOO LATE IN THE DAY. FIRE WEATHER CONDITIONS LOOK
TO BE FAIRLY LOCALIZED AND NOT WIDESPREAD ENOUGH FOR A LONG ENOUGH
DURATION TO ISSUE ANY FIRE WEATHER HIGHLITES AT THIS TIME. SEE
FIRE WEATHER DISCUSSION BELOW FOR MORE DETAILS.
SHOWERS AND STORMS WILL END AFTER SUNSET AS THIS FRONT MOVES THROUGH
THE REGION FOR A COOLER AND CLEAR NIGHT. TUESDAY WILL BE MUCH DRIER
WITH LITTLE IN THE WAY OF STORM ACTIVITY EXPECTED. ANOTHER UPPER
LEVEL DISTURBANCE WILL MOVE THROUGH MONTANA AND NE WYOMING
TUESDAY AFTERNOON/EVENING PROVIDING A REINFORCING SHOT OF COOLER
AIR TUESDAY NIGHT. EXPECT COOLER TEMPERATURES ON TUESDAY IN THE
WAKE OF THE COLD FRONT WITH HIGHS A FEW DEGREES BELOW NORMAL.
WINDS WILL BE BREEZY TUESDAY AFTERNOON ESPECIALLY ACROSS SW
COLORADO WHERE LOCALIZED FIRE WEATHER CONDITIONS ARE POSSIBLE.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
MODERATE NORTHWEST FLOW WILL CONTINUE INTO TUE NIGHT AND ANOTHER
SHORTWAVE TROUGH WILL SLIDE JUST EAST OF THE FORECAST AREA. FIRE
WEATHER CONCERNS WILL CONTINUE...ESPECIALLY OVER NW CO...BUT THE
TIGHTEST GRADIENT WILL HOLD OFF UNTIL AFTER MIDNIGHT AND AFTER
THE HUMIDITY WILL HAVE RISEN ABOVE CRITERIA.
WED AND THU...THE GRADIENT RELAXES AS LOW PRESSURE PUSHES TO THE
EAST AND DRY CONDITIONS PREVAIL. ON FRIDAY AND SATURDAY ANOTHER
TROUGH WILL MOVE ACROSS THE NORTHERN TIER STATES. THE GFS AND EC
ARE FINALLY SHOWING SOME AGREEMENT AND RUN TO RUN CONSISTENCY.
BOTH KEEP THE TROUGH CLOSER TO THE U.S. AND CANADIAN BORDER...
THOUGH THE PRESSURE GRADIENT OVER THE FORECAST AREA WILL INCREASE
FRIDAY NIGHT THROUGH SAT EVENING AND SOME MOISTURE WILL BE DRAWN
NORTH FROM AZ AND NM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1145 AM MDT MON AUG 17 2015
SCATTERED -SHRA/-TSRA CAN BE EXPECTED OVER THE COLORADO WESTERN
SLOPE TODAY. SOME STORMS COULD BE STRONG WITH LOCAL G40KTS AND
5SM +TSRAGS THAT WILL RESULT IN CIGS FALLING BELOW ILS BREAKPOINTS
FOR THE MOUNTAIN TAF SITES. LOWER ELEVATED TAF SITES SUCH AS
KGJT...KRIL...AND KMTJ WILL HAVE LOCALIZED G40KTS FROM THUNDERSTORM
OUTFLOW WINDS IN ADDITION TO BRIEF TSRA.
A COLD FRONT PUSHES INTO NW COLORADO TONIGHT THAT WILL PUSH
THUNDERSTORMS EAST OF THE DIVIDE. IN ADVANCE OF THIS COLD FRONT
THROUGH 03Z THIS EVENING...AREAS G25-30KTS WILL OCCUR OVER NE UTAH
AND NW COLORADO.
NO SIGNIFICANT WEATHER IS EXPECTED AFTER 08Z TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 1145 AM MDT MON AUG 17 2015
DEEP MIXED LAYER WILL RESULT THIS AFTERNOON AS LOWER SURFACE
PRESSURE OVER NW COLORADO DEVELOPS. SUSTAINED WINDS OF 15-20 MPH
IS EXPECTED WITH PEAK GUSTS OF 35 MPH IN ADVANCE OF A COLD FRONT.
HIGHER RESOLUTION MODELS INDICATE THAT DEW POINT VALUES WILL DROP
QUICKLY WHEN THE SURFACE WINDS DEVELOP. THE HRRR MODEL SHOW VALUES
FALLING INTO THE 20S ACROSS MOFFAT COUNTY (FIRE WEATHER ZONE
200)...WHICH IS BELOW MOS GUIDANCE VALUES. SPLIT THE DIFFERENCE
BETWEEN THE HRRR AND GUIDANCE...THE NET RESULT IS HUMIDITY VALUES
OF 10-15% AFTER 20Z (2 PM). THE WINDS MAY PERSIST THROUGH THE
EARLY EVENING HOURS GIVEN TIGHTENING PRESSURE GRADIENTS. CRITICAL
FIRE WEATHER CONDITIONS MAY PERSIST UNTIL AFTER SUNSET.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING UNTIL 9 PM MDT THIS EVENING FOR COZ200-202.
UT...NONE.
&&
$$
UPDATE...JRP
SHORT TERM...MDA
LONG TERM...CC
AVIATION...PF
FIRE WEATHER...PF
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1042 AM MDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1035 AM MDT MON AUG 17 2015
UPDATED TO INCLUDE SOME SHOWERS AND ISOLATED THUNDERSTORMS IN SOME
LOWER ELEVATION ZONES IN CENTRAL PORTION OF OUR CWA BEGINNING THIS
MORNING...WHICH DEVELOPED EARLIER IN THE DAY THAN PREVIOUSLY
EXPECTED. THIS CONVECTIVE ACTIVITY HAS DEVELOPED IN THE NORTHERN
BOUNDS OF UPPER LEVEL DIFLUENCE.
UPDATE ISSUED AT 750 AM MDT MON AUG 17 2015
SURFACE BOUNDARY THAT CUTS ACROSS THE SRN PORTION OF THE FORECAST
AREA HAS BEEN THE TRIGGER MECHANISM FOR ISOLATED SHOWERS AND
THUNDERSTORMS. THE HRRR MODEL SHOWS ACTIVITY EXPANDING ACROSS THIS
AREA AS THE DAY PROGRESSES...BUT A BIT SLOW HANDLING THE CURRENT
ACTIVITY.
THE OTHER CONCERN IS THE POTENTIAL FOR RED FLAG CONDITIONS ACROSS
NW COLORADO...SPECIFICALLY ZONE 200. RAP13 SHOWING DEEPENING SURFACE
LOW (SUB 1000 MB) FROM RAWLINS TRAILING BACK TO SOUTHEAST UTAH.
UPSTREAM...THERE IS THERMAL GRADIENT THAT SPREADS INTO NW COLORADO
THIS EVENING. THE HRRR MODEL SHOWS SURFACE WINDS 15-20 KTS ACROSS
NW COLORADO THIS AFTERNOON. WITH DEEP MIXED LAYER...EXPECT GUSTY
WINDS TO DEVELOP. FIRST IMPRESSION IS THAT RED FLAG CONDITIONS
WILL BE MET...AT LEAST FOR FIRE WEATHER ZONE 200 AND POSSIBLY 202.
PLAN TO TAKE ANOTHER LOOK AT THIS ONCE 12Z GUIDANCE ARRIVES BEFORE
MAKING A FINAL DECISION.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
DRIER AIR BEGINS TO WORK ACROSS NORTHEAST UTAH AND NORTHWEST
COLORADO THIS AFTERNOON AS A 85 KT UPPER LEVEL JET REMAINS OVERHEAD.
THE BEST MOISTURE IS ALONG THE BOOKCLIFFS AND SOUTH ACROSS SOUTHEAST
UTAH AND SOUTHWEST COLORADO WHERE PRECIPITABLE WATER (PW) VALUES
RANGE FROM 0.75 TO 1.0 INCH. EXPECTING STORMS TO DEVELOP OVER THE
HIGHER TERRAIN BY LATE MORNING/EARLY AFTERNOON ACROSS WEST CENTRAL
AND SOUTHWEST COLORADO WITH STORMS DRIFTING AND IMPACTING VALLEYS BY
MID AFTERNOON THROUGH EARLY EVENING GIVEN SOME DECENT STORM MOTION
FROM WEST TO EAST AT 20 MPH. THERE IS SOME DECENT INSTABILITY AND
SHEAR SO EXPECTING SOME ROTATING STORMS WITH GOOD SUSTAINING
UPDRAFTS SIMILAR TO SUNDAY`S ENVIRONMENT. MAINLY BRIEF HEAVY
RAIN...SMALL HAIL AND GUSTY OUTFLOW WINDS CAN BE EXPECTED WITH
FREQUENT LIGHTNING.
AN UPPER LEVEL LOW PRESSURE TROUGH WILL MOVE THROUGH MONTANA AND
NORTHEAST WYOMING THIS AFTERNOON AND EVENING WITH AN ASSOCIATED COLD
FRONT MOVING THROUGH THIS EVENING. THERE IS A NOTICEABLE WIND SHIFT
FROM WEST TO NORTHWEST AS WELL AS A DECREASE IN PW VALUES BEHIND
THIS FRONT TO 0.25 TO 0.5 INCH RANGE. THE SHORT TERM MODELS ARE IN
PRETTY GOOD AGREEMENT WITH TIMING OF THE FRONT WHICH SHOW THE
FRONT MOVING THROUGH THE AREA THIS EVENING INTO EARLY TUESDAY
MORNING. FOLLOWED NAM12 GUIDANCE FOR TIMING WHICH SHOWS THE FRONT
THROUGH NE UTAH AND NW COLORADO BETWEEN 6 PM AND 9 PM AND THROUGH
SE UTAH AND WEST CENTRAL COLORADO BETWEEN 9 PM AND MIDNIGHT. THE
FRONT WILL BE EXITING THE REST OF THE AREA BY 3 AM. THE MODELS ARE
NOT PERFECT SO THIS TIMING MAY NOT BE EXACT BUT AT THIS TIME...IT
GIVES A GOOD APPROXIMATION.
ANOTHER CONCERN IS THE POTENTIAL FOR FIRE WEATHER CRITERIA TO BE MET
ACROSS NORTHWEST COLORADO LATE THIS AFTERNOON AND EVENING WHERE
DRIER AIR WILL BE IN PLACE. THE TIMING OF THE COLD FRONT IS
CRITICAL FOR WHEN AND IF RED FLAG CRITERIA WILL BE MET...WHICH AT
THIS TIME SEEMS TOO LATE IN THE DAY. FIRE WEATHER CONDITIONS LOOK
TO BE FAIRLY LOCALIZED AND NOT WIDESPREAD ENOUGH FOR A LONG ENOUGH
DURATION TO ISSUE ANY FIRE WEATHER HIGHLITES AT THIS TIME. SEE
FIRE WEATHER DISCUSSION BELOW FOR MORE DETAILS.
SHOWERS AND STORMS WILL END AFTER SUNSET AS THIS FRONT MOVES THROUGH
THE REGION FOR A COOLER AND CLEAR NIGHT. TUESDAY WILL BE MUCH DRIER
WITH LITTLE IN THE WAY OF STORM ACTIVITY EXPECTED. ANOTHER UPPER
LEVEL DISTURBANCE WILL MOVE THROUGH MONTANA AND NE WYOMING
TUESDAY AFTERNOON/EVENING PROVIDING A REINFORCING SHOT OF COOLER
AIR TUESDAY NIGHT. EXPECT COOLER TEMPERATURES ON TUESDAY IN THE
WAKE OF THE COLD FRONT WITH HIGHS A FEW DEGREES BELOW NORMAL.
WINDS WILL BE BREEZY TUESDAY AFTERNOON ESPECIALLY ACROSS SW
COLORADO WHERE LOCALIZED FIRE WEATHER CONDITIONS ARE POSSIBLE.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 357 AM MDT MON AUG 17 2015
MODERATE NORTHWEST FLOW WILL CONTINUE INTO TUE NIGHT AND ANOTHER
SHORTWAVE TROUGH WILL SLIDE JUST EAST OF THE FORECAST AREA. FIRE
WEATHER CONCERNS WILL CONTINUE...ESPECIALLY OVER NW CO...BUT THE
TIGHTEST GRADIENT WILL HOLD OFF UNTIL AFTER MIDNIGHT AND AFTER
THE HUMIDITY WILL HAVE RISEN ABOVE CRITERIA.
WED AND THU...THE GRADIENT RELAXES AS LOW PRESSURE PUSHES TO THE
EAST AND DRY CONDITIONS PREVAIL. ON FRIDAY AND SATURDAY ANOTHER
TROUGH WILL MOVE ACROSS THE NORTHERN TIER STATES. THE GFS AND EC
ARE FINALLY SHOWING SOME AGREEMENT AND RUN TO RUN CONSISTENCY.
BOTH KEEP THE TROUGH CLOSER TO THE U.S. AND CANADIAN BORDER...
THOUGH THE PRESSURE GRADIENT OVER THE FORECAST AREA WILL INCREASE
FRIDAY NIGHT THROUGH SAT EVENING AND SOME MOISTURE WILL BE DRAWN
NORTH FROM AZ AND NM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 357 AM MDT MON AUG 17 2015
VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES FOR THE NEXT 24
HOURS. A WEAK COLD FRONT MOVING THROUGH THE AREA THIS MORNING
WILL CAUSE A BAND OF ISOLATED SHOWERS AND THUNDERSTORMS CUTTING
ACROSS CENTRAL AND SOUTHWEST CO. KMTJ AND KTEX SHOULD HAVE VCSH
THROUGH ABOUT 15Z.
FROM 19Z TO ABOUT 04Z ANOTHER WEAK FRONT WILL MOVE ACROSS THE
AREA FROM NW TO SE. ISOLD TO SCATTERED SHOWERS AND THUNDERSTORMS
WILL DEVELOP ALONG WITH GUSTY NORTHWEST WINDS. EXPECT MECHANICAL
TURBULENCE OVER RIDGES.
&&
.FIRE WEATHER...
ISSUED AT 357 AM MDT MON AUG 17 2015
AN UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE NORTHERN ROCKIES
THIS AFTERNOON AND EVENING WITH A COLD FRONT MOVING THROUGH EASTERN
UTAH AND WESTERN COLORADO DURING THE EVENING HOURS. BREEZY
CONDITIONS WILL EXIST ACROSS NORTHWEST COLORADO DURING THE AFTERNOON
AND EVENING WITH THE BEST WINDS OCCURRING BETWEEN 6 PM AND 9 PM. THE
KEY PIECE HERE IS THE TIMING OF A COLD FRONT WHICH LOOKS TO MOVE
THROUGH NORTHWEST COLORADO BETWEEN 6 PM AND 9 PM THIS EVENING.
LOCALIZED FIRE WEATHER CONDITIONS ARE POSSIBLE DURING THIS TIME BUT
DOES NOT LOOK WIDESPREAD ENOUGH FOR A LONG ENOUGH DURATION TO ISSUE
FIRE WEATHER HIGHLITES. THE FRONTAL TIMING IS A BIT TOO LATE WHEN
THE COMBINATION OF LOW RH AND WINDS TO 25 MPH WILL BE MET. THIS IS
SOMETHING THAT BEARS WATCHING DEPENDING ON THE TIMING OF THE COLD
FRONT. TUESDAY WILL BE DRIER ACROSS THE REGION WITH BREEZY
CONDITIONS POSSIBLE FOR SW COLORADO WHICH ALSO BEARS WATCHING.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...RED FLAG WARNING FROM 2 PM THIS AFTERNOON TO 9 PM MDT THIS
EVENING FOR COZ200-202.
UT...NONE.
&&
$$
UPDATE...JRP
SHORT TERM...MDA
LONG TERM...CC
AVIATION...CC
FIRE WEATHER...MDA
AREA FORECAST DISCUSSION
NWS GOODLAND KS
252 PM MDT MON AUG 17 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 250 PM MDT MON AUG 17 2015
EARLY AFTERNOON WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOW
STRENGTHENING TROUGH ACROSS MONTANA WITH SHARP PV HEIGHT ANOMALY
DIGGING INTO NORTHWESTERN WYOMING. DIFFLUENT FLOW IS IN PLACE
ACROSS NORTHERN COLORADO WITH INCREASING DIVERGENT SIGNATURE
AHEAD OF APPROACHING UPPER LEVEL JET. AT THE SURFACE A STATIONARY
FRONT EXTENDS FROM NORTH CENTRAL KANSAS TO SOUTHEAST
COLORADO...ACROSS THE SOUTHEAST PART OF OUR CWA...WITH A WEAK
SURFACE TROUGH AXIS EXPENDING ACROSS THE NW PART OF OUR FORECAST
AREA.
THUNDERSTORMS SHOULD INITIATE ACROSS EASTERN COLORADO THIS
AFTERNOON WITH ACTIVITY INCREASING IN COVERAGE AND SPREADING EAST
INTO OUR CWA THROUGH THE EVENING/OVERNIGHT. BEST FORCING IS
ADVERTISED 03-06Z OVER OUR CWA AND QUICKLY TRANSITIONS EASTWARD
THROUGH TUESDAY MORNING. AS THE UPPER LOW DEEPENS AND EVENTUALLY
CLOSES OFF OVER NEBRASKA DRY SLOT/SUBSIDENT REGION WILL MOVE OVER
OUR CWA WHICH SHOULD RAPIDLY DECREASE ANY SHOWER/THUNDERSTORM
CHANCES. STRONG COLD FRONT WILL DROP DOWN ACROSS THE REGION
TUESDAY MORNING AND COMBINED WITH INCREASING SUBSIDENCE BRING
MILD/WINDY (VERY FALL-LIKE) CONDITIONS TO OUR CWA. THERE MAY ALSO
BE A REDEVELOPMENT OF DENSE FOG/LOW STRATUS OVER SW NEBRASKA
DEPENDING ON THUNDERSTORM ACTIVITY/MIXING AND FRONTAL TIMING.
REGARDING SEVERE POTENTIAL TONIGHT...RAP ANALYSIS SHOWS SB CAPE
AXIS 2500-3500 J/KG AND DEEP BULK EFFECTIVE SHEER VALUES 40-50KT
ACROSS EASTERN COLORADO. CONSIDERING THE DEEP LAYER SHEER AND
INSTABILITY WE ARE ANTICIPATING ORGANIZED SUPERCELLS DEVELOPING
LATE THIS AFTERNOON AND SLOWLY PROGRESSING EASTWARD (MEAN STORM
MOTIONS 10-20KT). THERE IS A WINDOW WITH LOW LEVEL TURNING ALONG
SURFACE TROUGH AXIS FOR TORNADOES WITH MORE ORGANIZED CELLS...WITH
PRIMARY THREAT VERY LARGE HAIL (2"+) AND DAMAGING WINDS. AS THIS
ACTIVITY ORGANIZES INTO A MCS/THUNDERSTORM CLUSTER TORNADO THREAT
SHOULD DIMINISH. TORNADO WATCH 490 IS CURRENTLY IN EFFECT FOR OUR
EASTERN COLORADO COUNTIES...AND PATTERN IS BEING MONITORED FOR
ANY OTHER POSSIBLE SEVERE WATCHES AS THIS UNFOLDS THIS
AFTERNOON/EVENING.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 156 PM MDT MON AUG 17 2015
JET MAX ROTATING AROUND BACK OF THE UPPER TROUGH WILL BRING
SCATTERED SHOWERS TO THE AREA TUESDAY NIGHT THROUGH WEDNESDAY
MORNING UNDER THE DIVERGENT LEFT EXIT REGION. MODEL QPF IS
LIGHT...GENERALLY BETWEEN A TENTH AND A QUARTER OF AN INCH...BUT
RATHER WIDESPREAD SO POPS MAY NEED TO BE INCREASED IF THOSE TRENDS
CONTINUE. POINT FORECAST SOUNDINGS ACTUALLY SHOW ICE IN THE COLUMN
BUT THE SURFACE BASED WARM LAYER EXTENDS TO AROUND 6KFT AGL WHICH
WILL BE MORE THAN SUFFICIENT TO KEEP ANY KIND OF SNOW FROM
REACHING THE GROUND. LOW TEMPERATURES A BIT TRICKY...WITH CLOUDS
POTENTIALLY KEEPING THEM FROM REACHING THE UPPER 40S BUT IF THE
RAIN IS PROLONGED MIGHT WET BULB DOWN TO NEAR THAT ANYWAY. EITHER
WAY IT WILL BE A RATHER CHILLY MORNING FOR MID AUGUST.
UPPER TROUGH WILL MOVE OUT WEDNESDAY AFTERNOON WITH NORTHWEST
FLOW ALOFT THROUGH THE END OF THE WEEK. PRECIPITATION CHANCES
DURING THAT TIME WILL BE SLIM TO NONE WITH NO UPPER SHORTWAVES IN
THE MODELS AND LIMITED MOISTURE AVAILABLE. TEMPERATURES WILL
REBOUND QUICKLY AFTER THE MIDWEEK COOL DOWN WITH ABOVE NORMAL
HIGHS BY FRIDAY. THE UPPER FLOW WILL TRANSITION TO ZONAL AND THEN
SOUTHWEST OVER THE WEEKEND AS ANOTHER TROUGH DIGS INTO THE
NORTHERN ROCKIES. THE NEXT BEST CHANCE FOR THUNDERSTORMS WILL BE
SATURDAY AFTERNOON/EVENING AS DYNAMICS AND SURFACE COLD FRONT
ASSOCIATED WITH THAT SYSTEM MOVE THROUGH THE CENTRAL PLAINS. A
LITTLE EARLY...BUT RIGHT NOW BEST COMBINATION OF INSTABILITY AND
SHEAR WILL BE CONFINED TO EASTERN PARTS OF THE FORECAST
AREA...NORTON TO GOVE...WHICH WOULD BE THE FAVORED AREAS FOR ANY
SEVERE THREAT. IF THAT TIMING VERIFIES SUNDAY AND MONDAY WILL BE
DRY AND A LITTLE COOLER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1141 AM MDT MON AUG 17 2015
LOW STRATUS RESPONSIBLE FOR IFR/MVFR CIGS WILL SLOWLY LIFT THROUGH
THE AFTERNOON AS A WARM FRONT LIFTS NORTH TO BE NEAR KGLD.
THUNDERSTORMS SHOULD REDEVELOP ALONG AND SOUTH OF THIS FRONT LATE
THIS AFTERNOON AND SLOWLY SPREAD EAST. BETTER COVERAGE MAY END UP
REMAINING SOUTH OF KMCK OVER KGLD...HOWEVER THERE WILL BE AT LEAST
SCATTERED COVERAGE ACROSS SW NEBRASKA AS UPPER LEVEL SYSTEM MOVES
INTO THE NORTHERN PLAINS. LOW LEVEL MOISTURE AND LIGHT EASTERLY
WINDS WILL HELP WITH STRATUS/FOG REDEVELOPMENT LATE TONIGHT
THROUGH EARLY TUESDAY MORNING AT KMCK. VFR CONDITIONS SHOULD
PREVAIL AT KGLD AFTER THUNDERSTORM ACTIVITY MOVES EAST TONIGHT. A
STRONG COLD FRONT MOVING THROUGH THE REGION 13-16Z WILL HELP
IMPROVE CONDITIONS AT KMCK...AND WILL BRING GUSTY NORTH WINDS TO
BOTH TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...024
AVIATION...DR
AREA FORECAST DISCUSSION
NWS WICHITA KS
1233 PM CDT MON AUG 17 2015
...UPDATED FOR 18Z AVIATION DISCUSSION...
.SYNOPSIS...
ISSUED AT 317 AM CDT MON AUG 17 2015
CONVECTION IS DECREASING IN AREAL EXTENT BUT CONTINUING ACROSS
SOUTHWEST KANSAS AND OVER NORTH CENTRAL KANSAS AND NORTHEAST INTO
SOUTHEAST NEBRASKA. THIS SCATTERED CONVECTION IS EXPECTED TO
LINGER...BUT DIMINISH INTO THE EARLY MORNING HOURS.
BILLINGS WRIGHT
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
TODAY - TONIGHT: THE HIGH RESOLUTION GUIDANCE HRRR AND THE HIGHER
RESOLUTION NAM12 STRUGGLE TO SHOW MUCH CONVECTION PERSISTING
ACROSS CENTRAL KANSAS DURING THE EARLY PART OF THE DAY. A PIECE
OF ENERGY WILL APPROACH THE AREA FROM THE NORTHWEST DURING THE
LATE AFTERNOON HOURS WHICH WILL INCREASE THE CHANCES FOR
CONVECTION INTO THE EVENING ESPECIALLY OVER CENTRAL AND SOUTH
CENTRAL KANSAS. SHEAR WILL BE LACKING...BUT THERE IS A MODEST
1000-1500 J/KG CAPE FOR THUNDERSTORMS TO POTENTIALLY BE
STRONG...AND WITH THE WEAK FLOW...FLOODING COULD BE A CONCERN AS
WELL. MOISTURE TRANSPORT INCREASES DURING THE OVERNIGHT HOURS
INCREASING THE PRECIPITATION CHANCES FOR SOUTH CENTRAL KANSAS.
TUESDAY - WEDNESDAY:
THE STRONGER UPPER LEVEL WAVE WILL MOVE INTO THE REGION DURING THE
DAY TUESDAY...BUT THE MAIN FRONTAL PUSH WILL BE LATER TUESDAY
EVENING WHEN THE UPPER LOW DIGS SLIGHTLY DEEPER. THE UPPER PV
ENERGY MOVING ACROSS THE AREA TUESDAY WILL INCREASE THE CHANCE
FOR THUNDERSTORMS THROUGHOUT THE DAY. THE UPPER WAVE WILL BE
CLOSER TO KANSAS INCREASING THE UPPER SHEAR PROFILE. SEVERE STORMS
MAY BE POSSIBLE ESPECIALLY OVER CENTRAL AND NORTHERN PORTIONS OF
SOUTH CENTRAL KANSAS WHERE THE COMBINATION OF SHEAR AND
INSTABILITY ARE ANTICIPATED TO BE THE GREATEST. ELSEWHERE STORMS
COULD BE STRONG.
BY TUESDAY NIGHT THE MAIN COLD FRONT/WIND SHIFT WILL BEGIN MOVING
ACROSS CENTRAL AND EASTERN KANSAS. THUNDERSTORMS ALONG THE FRONT
ARE POSSIBLE...BUT THE CONVERGENCE ISN`T OVERWHELMING. THE FRONT
IS EXPECTED TO BE FAIRLY PROGRESSIVE AND MOVE THROUGH THE AREA BY
EARLY MORNING WEDNESDAY. A FEW STRONGER STORMS REMAIN POSSIBLE
ALONG THE FRONT.
A SECONDARY PIECE OF ENERGY WILL MOVE SOUTHWARD INTO THE UPPER LOW
CAUSING THE POTENTIAL FOR SCATTERED SHOWERS DURING THE DAY
WEDNESDAY.
THE FRONT WILL CAUSE TEMPERATURES ON WEDNESDAY TO BE SIGNIFICANTLY
COOLER THAN RECENT DAYS...STEADILY COOLING FROM A HIGH CLOSE TO
NORMAL TODAY IN THE LOW 90S TO THE LOW TO MID 70S BY WEDNESDAY.
BILLINGS WRIGHT
.LONG TERM...(THURSDAY THROUGH SUNDAY)
ISSUED AT 317 AM CDT MON AUG 17 2015
WHILE THERE ARE SOME SLIGHT DISCREPANCIES AMONGST THE MEDIUM
RANGE GUIDANCE...THE PATTERN REMAINS ACTIVE AND GENERALLY IN
FAIRLY GOOD AGREEMENT. ZONAL FLOW WILL RETURN BRIEFLY AHEAD OF THE
NEXT SYSTEM FOR THE WEEKEND...BUT BEFORE THAT A WEAK TROUGH WILL
IMPACT THE AREA FOR THE END OF THE WEEK.
THE WEAK TROUGH MAY BRING CHANCES FOR RAIN THURSDAY NIGHT AND
FRIDAY...BUT CONFIDENCE IS LOWER DUE TO DISCREPANCIES.
TEMPERATURES WILL STEADILY INCREASE BACK INTO THE 80S...BUT THE
NEXT FRONT WILL APPROACH AND TRAVERSE THE AREA SATURDAY
NIGHT/SUNDAY MORNING. THIS FRONT WILL BRING THE NEXT BEST CHANCE
OF RAIN TO THE REGION. THIS PERIOD HAS HIGHER CONFIDENCE DUE TO
BETTER AGREEMENT ACROSS VARIOUS MODEL SOLUTIONS.
BILLINGS WRIGHT
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1229 PM CDT MON AUG 17 2015
VFR CONDITIONS SHOULD BE THE RULE FOR THIS FORECAST PERIOD WITH
SOME VCTS NOTED FOR ALL SITES EXCEPT FOR KCNU. CURRENT BOUNDARY TO
THE NORTHWEST WILL SLOWLY PROGRESS ACROSS THE FORECAST AREA ON
TUESDAY BRINGING A CHANGE IN WEATHER TO THE AREA. WINDS WILL
INCREASE EARLY ON TUESDAY MORNING AND THEN BEGIN A TRANSITION TO A
NORTHEASTERLY DIRECTION BY THE END OF TUESDAY. AHEAD OF THE
BOUNDARY...VERY LITTLE CONVERGENCE SEEMS TO BE PRESENT AND THE
UPPER SUPPORT SEEMS TO BE WANING A BIT. SO CHANCES FOR TRW ARE
DECREASING THIS AFTERNOON AND OVERNIGHT. SLIGHTLY BETTER CHANCES
WILL OCCUR LATER ON TUESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 90 71 84 60 / 20 50 60 70
HUTCHINSON 90 70 85 58 / 20 50 50 60
NEWTON 89 69 84 57 / 20 50 50 70
ELDORADO 90 71 84 58 / 20 50 60 70
WINFIELD-KWLD 91 71 85 60 / 20 50 60 70
RUSSELL 88 66 83 54 / 20 50 60 30
GREAT BEND 89 68 85 55 / 20 50 60 40
SALINA 90 70 85 57 / 20 50 60 50
MCPHERSON 90 70 85 57 / 20 50 50 60
COFFEYVILLE 91 72 86 64 / 20 40 60 70
CHANUTE 90 72 84 61 / 20 40 60 70
IOLA 90 71 83 61 / 20 40 60 70
PARSONS-KPPF 91 71 85 62 / 20 30 60 70
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
239 PM EDT MON AUG 17 2015
...UPDATED AVIATION DISCUSSION...
.SHORT TERM (NOW THROUGH TUESDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
MOISTURE WILL CONTINUE TO ADVECT INTO THE REGION FROM THE SOUTH THIS
PERIOD. AN UPPER LEVEL LOW NOW ALONG THE SOUTHERN IN/IL BORDER WILL
TRAVEL NORTH AND THEN START HEADING NORTHEAST BY LATER THIS
AFTERNOON. ALREADY SEEING SOME LIGHT RADAR RETURNS OVER SOUTH
CENTRAL TN THIS HOUR...IN AN AREA OF ENHANCED LIFT ON THE SOUTH SIDE
OF A WEAK UPPER JET. THESE RAINS SHOULD LIFT NORTHWARD THIS MORNING.
ANOTHER AREA OF SHOWERS SHOULD DEVELOP ALONG THE OHIO RIVER THIS
MORNING...WHERE THE LATEST RAP PLACES A THETA-E RIDGE.
THE CHANCE FOR AFTERNOON THUNDERSTORMS WILL DEPEND PARTLY ON HOW
MANY BREAKS WE GET IN THE CLOUDS TODAY. IT WILL NOT TAKE MUCH...AS
COOLER AIR ALOFT WITH THE PASSAGE OF THE UPPER LOW WILL MEAN SOME
ELEVATED INSTABILITY AS WELL. GIVEN THE CLOUD COVER THOUGH...THINK
THE RISK FOR SEVERE WEATHER IS FAIRLY LOW.
TONIGHT THAT WAVE SHOULD BE HEADING TOWARD NORTHERN OHIO. THAT SAID
THOUGH...IT WILL LEAVE A TRAILING TROUGH THAT MAY ALLOW FOR
CONTINUED STORM DEVELOPMENT OVER THE SOUTHEAST HALF OF OUR FORECAST
AREA. THAT AREA WILL CONTINUE TO SEE THE BEST CHANCES ON TUESDAY.
MAY HAVE TO MONITOR FOR FLOOD THREAT DOWN THERE AS OUR SOUTHEAST
COUNTIES HAVE LOWER FLASH FLOOD GUIDANCE. STILL CURRENT QPF IS WELL
BELOW THAT GUIDANCE, BUT SHOULD LATER FORECASTS TREND UP MORE WE
MAYNEED A WATCH.
CLOUD COVER SHOULD LIMIT HIGH TEMPERATURES TO BELOW NORMAL TODAY AND
TUESDAY...WHEREAS LOWS WILL BE A LITTLE ABOVE NORMAL. ONLY OTHER
CONCERN WOULD BE PATCHY FOG BOTH THIS MORNING AND TOMORROW MORNING,
WITH COVERAGE LIMITED BOTH DAYS ALSO BY CLOUD COVER.
.LONG TERM (TUESDAY NIGHT THROUGH SUNDAY)...
ISSUED AT 315 AM EDT MON AUG 17 2015
TUESDAY NIGHT...
WEAK SOUTHWEST FLOW WILL BE IN PLACE AHEAD OF A STRONG NORTH CENTRAL
CONUS TROUGH TO START THE LONG TERM. MAINLY DIURNALLY DRIVEN
SCATTERED T-STORMS ARE EXPECTED TO BE ONGOING ACROSS OUR SE CWA
TUESDAY EVENING, HOWEVER THESE SHOULD GRADUALLY DIMINISH AS WE HEAD
INTO THE OVERNIGHT HOURS. CAN`T GO COMPLETELY DRY AS THERE IS A
SIGNAL FOR SOME LOW LEVEL JETTING THROUGH THE OVERNIGHT. SOUTHERLY
WINDS SHOULD INCREASE TOWARD DAWN, HELPING LOWS TO STAY ON THE MILD
SIDE. LOOK FOR MAINLY LOW 70S.
WEDNESDAY - THURSDAY...
STRONG SHORTWAVE TROUGH AND ITS ASSOCIATED SURFACE LOW WILL MOVE
FROM THE UPPER MIDWEST TO LAKE SUPERIOR BY LATE WEDNESDAY NIGHT.
DEEP MOISTURE WILL POOL INTO THE OHIO RIVER VALLEY AHEAD OF THE
TROUGH AND SURFACE FRONT TRAILING FROM THE LOW. MEANWHILE, STRONGER
DEEP FLOW WILL ALSO OVERSPREAD THE REGION BY WEDNESDAY NIGHT. LOOK
FOR SCATTERED TO NUMEROUS THUNDERSTORMS DURING THE DAY ON WEDNESDAY
WITH HIGHS MAINLY IN THE LOW 80S. A FEW OF THE STORMS COULD BE
STRONG IF MODERATE INSTABILITY IS REALIZED, ALTHOUGH BETTER DEEP
SHEAR AND FORCING DOESN`T ARRIVE UNTIL LATER WEDNESDAY NIGHT. WE`LL
HAVE TO CONTINUE TO KEEP AN EYE ON POTENTIAL FOR AN ORGANIZED SEVERE
THREAT LATER WEDNESDAY EVENING INTO WEDNESDAY NIGHT, ALTHOUGH SOME
LIMITING FACTORS COULD BE TIMING OF PASSAGE/MORE LIMITED INSTABILITY
AND BEST FORCING NORTH OF THE CWA. WILL CONTINUE TO MENTION HEAVY
RAIN AND GUSTY WINDS AS THE MAIN POTENTIAL THREATS IN THE HWO.
COLD FRONT LOOKS TO PASS THROUGH EARLY THURSDAY MORNING ACROSS THE
NW AND THROUGH MOST OF THE CWA BY LATE THURSDAY MORNING. IF PASSAGE
IS SLOW ENOUGH, SOME REDEVLOPMENT COULD OCCUR ACROSS OUR FAR E OR SE
THURSDAY AFTERNOON, WHERE SOME STRONGER/PULSY STORMS WOULD BE
POSSIBLE. OTHERWISE, SKIES WILL BECOME GRADUALLY CLEARER WITH
TEMPERATURES ONLY TOPPING OUT IN THE MID OR UPPER 70S.
THURSDAY NIGHT - SUNDAY...
THE FRONT COULD HANG UP ACROSS OUR SOUTH TO END THE WEEK AND HEAD
INTO THE WEEKEND SO WILL KEEP ISOLATED TO WIDELY SCATTERED CHANCES
ACROSS THE SOUTH THROUGH SATURDAY. THE NORTH WILL BE DRY DURING THIS
TIME CLOSER TO THE SURFACE HIGH CENTER. THURSDAY NIGHT LOWS LOOK TO
DROP INTO THE UPPER 50S NORTH AND LOWER 60S SOUTH THURSDAY NIGHT.
CAN`T RULE OUT A FEW MID 50S IN OUR TYPICAL COOL NORTH SPOTS. HIGHS
ON FRIDAY WILL MODERATE A BIT, FINDING THEIR WAY BACK TO THE LOW
80S. FRIDAY NIGHT WILL BE SLIGHTLY MILDER WITH LOWS BACK IN THE LOW
AND MID 60S. SATURDAY BRINGS HIGHS IN THE LOW AND MID 80S.
STORM CHANCES MAY INCREASE ON SUNDAY AHEAD OF ANOTHER MID LEVEL
DISTURBANCE AND ASSOCIATED SURFACE FRONT. HOWEVER, CONFIDENCE IS LOW
IN TIMING OF THIS FEATURE SO WILL ONLY MENTION LOW CHANCES AT THIS
TIME.
&&
.AVIATION (18Z TAF UPDATE)...
ISSUED AT 238 PM EDT MON AUG 17 2015
LIGHT RAIN WILL CONTINUE IN THE LEX AREA FOR MUCH OF THE AFTERNOON
BUT SHOULDN`T CAUSE MUCH OF A PROBLEM FOR AVIATION. BWG AND SDF
SHOULD REMAIN IN A GAP BETWEEN RAIN TO THE EAST AND SHOWERS/STORMS
TO THE WEST, THOUGH A FEW SHOWERS AT THE AIRPORTS STILL POSSIBLE.
LOW LEVEL MOISTURE IS EXPECTED TO CONDENSE INTO A LOW CEILING LATE
TONIGHT INTO THE MORNING HOURS ON TUESDAY, WITH AT LEAST MVFR FLYING
CONDITIONS EXPECTED.
WINDS THROUGH THE TAF PERIOD WILL BE LIGHT.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
SHORT TERM........RJS
LONG TERM.........BJS
AVIATION..........13
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
619 PM EDT MON AUG 17 2015
.SYNOPSIS...
WARM...HUMID...AND UNSETTLED WEATHER IS EXPECTED THROUGH MUCH OF
THE WEEK UNTIL THE PASSAGE OF A COLD FRONT THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
WITH 615PM UPDATE...ADJUSTED HOURLY TEMPERATURE TRENDS AS TEMPS
HAVE STAYED UP A FEW DEGREES DESPITE DIURNAL CU. ALSO ADJUSTED SKY
COVER AS OVERCAST MID LEVEL CLOUDS ARE GENERALLY WEST OF THE
FORECAST AREA AND DIURNAL CUMULUS IS ALREADY STARTING TO
DISSIPATE. 18Z NAM/GFS HAVE STARTED COMING IN THE DIRECTION OF THE
HRRR...WHICH WAS PREVIOUSLY NOTED AS HAVING GREATER PRECIPITATION
COVERAGE. HAVE NOT MADE ANY ADJUSTMENTS TO THAT PORTION OF THE
FORECAST YET...BUT WILL CONTINUE TO MONITOR UPSTREAM PRECIPITATION
TRENDS. PREVIOUS DISCUSSION FOLLOWS.
VERY SMALL ADJUSTMENTS MADE TO THE FORECAST THROUGH THE AFTERNOON
AS LOW PRESSURE...APPARENT IN VISIBLE AND WV SATELLITE IMAGERY
OVER ILLINOIS...GETS ABSORBED IN THE UPPER LEVEL FLOW. WHILE LOW
LEVEL MOISTURE WILL INCREASE AHEAD OF THIS APPROACHING WAVE...WARM
AIR ALOFT AND LITTLE SUPPORT FOR LIFT SHOULD KEEP MUCH OF THE
FORECAST AREA DRY TODAY...SAVE FOR SOME CONVECTION OVER THE HIGHER
TERRAIN AND WITH THE LAKE BREEZE. WITH THIS IN MIND...LOW CHANCE
POPS WERE MAINTAINED. WEAK SHEAR WILL KEEP ANY STORMS BELOW SEVERE
THRESHOLDS.
THE AFOREMENTIONED SHORTWAVE WILL PIVOT ACROSS THE UPPER OHIO
VALLEY OVERNIGHT. WHILE WE WILL LOSE MOST OF THE
INSTABILITY...THIN ELEVATED CAPE OVERNIGHT ON THE BUFKIT SOUNDINGS
WARRANTED AT LEAST A SLIGHT CHANCE THUNDER MENTION. THE HRRR IS
MOST AGGRESSIVE WITH THE PRECIPITATION COVERAGE VERSUS THE OTHER
HI RES MODELS OVERNIGHT. CONSIDERING THE LACK OF UPPER LEVEL JET
SUPPORT...WILL KEEP POPS IN THE CHANCE CATEGORY BUT ADJUST TIMING
CLOSE TO THE HRRR. LINGERING CLOUD COVER SHOULD KEEP TEMPERATURES
ELEVATED OVERNIGHT.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/...
DEEPENING UPPER TROUGH AND STRENGTHENING SURFACE LOW OVER THE
NORTHERN PLAINS WILL CONTINUE THE FEED WARMTH AND MOISTURE IN
SOUTHWEST FLOW UNTIL A COLD FRONT APPROACHES ON THURSDAY.
THUS...WHILE THE UPPER SHORTWAVE ON TUESDAY WILL BE DEPARTING TO
THE EAST...WILL KEEP A CHANCE FOR SHOWERS AND THUNDERSTORMS
THROUGH THE AFTERNOON AND ADDITIONAL CHANCES ON WEDNESDAY WITH YET
ANOTHER SHORTWAVE. WARM AIR ALOFT SHOULD HOLD MOST STORMS BELOW
SEVERE LEVELS UNTIL THE COLD FRONT APPROACHES.
LATEST MODEL GUIDANCE DIFFERS WITH THE TIMING OF THE FRONTAL
PASSAGE ON THURSDAY WHICH WOULD HAVE IMPLICATIONS ON THE STRENGTH
OF ANY CONVECTION OUT AHEAD OF IT. REGARDLESS...LATE WEDNESDAY AND
THURSDAY LOOK TO BE THE BETTER DAYS FOR INSTABILITY AND
SHEAR...WHICH PROMPTED A MARGINAL RISK FOR SEVERE OVER OUR OHIO
ZONES...CLOSER TO THE UPPER LEVEL JET. WILL CONTINUE TO MONITOR
THIS RISK AS THE FRONT APPROACHES.
TEMPERATURES SHOULD STAY CLOSE TO SEASONAL AVERAGES THROUGH THE
PERIOD.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
COLD FRONT PASSAGE IS PROGGED FOR LATE THURSDAY AND AFTER THIS
TIME MORE SEASONABLE CONDITIONS ARE ANTICIPATED. LATEST GUIDANCE
THEN KEEPS THE REGION DRY THROUGH THE REMAINDER OF THE LONG TERM.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE SLIDING EAST OF THE AREA AS AN UPPER-LEVEL TROF SLOWLY
APPROACHES FROM THE SOUTHWEST. ABUNDANT MIDDAY SUN HAS LED TO
ANOTHER DIURNAL CU-FIELD TO DEVELOP AND EVEN A FEW POP-UP SHOWERS
AND THUNDERSTORMS THROUGH CENTRAL OHIO. ALTHOUGH WEAK WIND SHEAR
THROUGH THE COLUMN WILL BE LIMITING...THE BETTER INSTABILITY OVER
OUR AREA MAY RESULT IN A FEW ISOLATED SHOWERS/THUNDERSTORMS
THROUGH THE EVENING...COVERAGE WILL BE TOO LIMITED FOR INCLUSION
IN ANY TAF CURRENTLY.
THE CLOSED UPPER-LEVEL TROF...CURRENTLY OVER THE LOWER OHIO RIVER
VALLEY WILL MOVE NORTHEAST TONIGHT SPREADING SHOWERS AND POSSIBLY
A FEW EMBEDDED THUNDERSTORMS ACROSS THE FORECAST AREA. TIMING HAS
BEEN A LITTLE TRICKY AS THE UPPER LOW TRANSITIONS TO AN OPEN
WAVE...BUT THE BEST CHANCE OF RAIN AND ANY ASSOCIATED RESTRICTIONS
WILL BE LATE IN THE OVERNIGHT AND EARLY TUESDAY MORNING. EXPECTING
LINGERING SHOWERS AND POSSIBLY THUNDERSTORMS BEHIND THE MAIN WAVE
THROUGH TUESDAY...ALTHOUGH RESTRICTIONS SHOULD REMAIN FAIRLY
LIMITED.
TAX
OUTLOOK...TUESDAY NIGHT THROUGH SATURDAY...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH A LATE
WEDNESDAY/THURSDAY COLD FRONT APPROACH AND PASSAGE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
214 PM EDT MON AUG 17 2015
.SYNOPSIS...
WARM...HUMID...AND UNSETTLED WEATHER IS EXPECTED THROUGH MUCH OF
THE WEEK UNTIL THE PASSAGE OF A COLD FRONT THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
VERY SMALL ADJUSTMENTS MADE TO THE FORECAST THROUGH THE AFTERNOON
AS LOW PRESSURE...APPARENT IN VISIBLE AND WV SATELLITE IMAGERY
OVER ILLINOIS...GETS ABSORBED IN THE UPPER LEVEL FLOW. WHILE LOW
LEVEL MOISTURE WILL INCREASE AHEAD OF THIS APPROACHING WAVE...WARM
AIR ALOFT AND LITTLE SUPPORT FOR LIFT SHOULD KEEP MUCH OF THE
FORECAST AREA DRY TODAY...SAVE FOR SOME CONVECTION OVER THE HIGHER
TERRAIN AND WITH THE LAKE BREEZE. WITH THIS IN MIND...LOW CHANCE
POPS WERE MAINTAINED. WEAK SHEAR WILL KEEP ANY STORMS BELOW SEVERE
THRESHOLDS.
THE AFOREMENTIONED SHORTWAVE WILL PIVOT ACROSS THE UPPER OHIO
VALLEY OVERNIGHT. WHILE WE WILL LOSE MOST OF THE
INSTABILITY...THIN ELEVATED CAPE OVERNIGHT ON THE BUFKIT SOUNDINGS
WARRANTED AT LEAST A SLIGHT CHANCE THUNDER MENTION. THE HRRR IS
MOST AGGRESSIVE WITH THE PRECIPITATION COVERAGE VERSUS THE OTHER
HI RES MODELS OVERNIGHT. CONSIDERING THE LACK OF UPPER LEVEL JET
SUPPORT...WILL KEEP POPS IN THE CHANCE CATEGORY BUT ADJUST TIMING
CLOSE TO THE HRRR. LINGERING CLOUD COVER SHOULD KEEP TEMPERATURES
ELEVATED OVERNIGHT.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY/...
DEEPENING UPPER TROUGH AND STRENGTHENING SURFACE LOW OVER THE
NORTHERN PLAINS WILL CONTINUE THE FEED WARMTH AND MOISTURE IN
SOUTHWEST FLOW UNTIL A COLD FRONT APPROACHES ON THURSDAY.
THUS...WHILE THE UPPER SHORTWAVE ON TUESDAY WILL BE DEPARTING TO
THE EAST...WILL KEEP A CHANCE FOR SHOWERS AND THUNDERSTORMS
THROUGH THE AFTERNOON AND ADDITIONAL CHANCES ON WEDNESDAY WITH YET
ANOTHER SHORTWAVE. WARM AIR ALOFT SHOULD HOLD MOST STORMS BELOW
SEVERE LEVELS UNTIL THE COLD FRONT APPROACHES.
LATEST MODEL GUIDANCE DIFFERS WITH THE TIMING OF THE FRONTAL
PASSAGE ON THURSDAY WHICH WOULD HAVE IMPLICATIONS ON THE STRENGTH
OF ANY CONVECTION OUT AHEAD OF IT. REGARDLESS...LATE WEDNESDAY AND
THURSDAY LOOK TO BE THE BETTER DAYS FOR INSTABILITY AND
SHEAR...WHICH PROMPTED A MARGINAL RISK FOR SEVERE OVER OUR OHIO
ZONES...CLOSER TO THE UPPER LEVEL JET. WILL CONTINUE TO MONITOR
THIS RISK AS THE FRONT APPROACHES.
TEMPERATURES SHOULD STAY CLOSE TO SEASONAL AVERAGES THROUGH THE
PERIOD.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
COLD FRONT PASSAGE IS PROGGED FOR LATE THURSDAY AND AFTER THIS
TIME MORE SEASONABLE CONDITIONS ARE ANTICIPATED. LATEST GUIDANCE
THEN KEEPS THE REGION DRY THROUGH THE REMAINDER OF THE LONG TERM.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
HIGH PRESSURE SLIDING EAST OF THE AREA AS AN UPPER-LEVEL TROF SLOWLY
APPROACHES FROM THE SOUTHWEST. ABUNDANT MIDDAY SUN HAS LED TO
ANOTHER DIURNAL CU-FIELD TO DEVELOP AND EVEN A FEW POP-UP SHOWERS
AND THUNDERSTORMS THROUGH CENTRAL OHIO. ALTHOUGH WEAK WIND SHEAR
THROUGH THE COLUMN WILL BE LIMITING...THE BETTER INSTABILITY OVER
OUR AREA MAY RESULT IN A FEW ISOLATED SHOWERS/THUNDERSTORMS
THROUGH THE EVENING...COVERAGE WILL BE TOO LIMITED FOR INCLUSION
IN ANY TAF CURRENTLY.
THE CLOSED UPPER-LEVEL TROF...CURRENTLY OVER THE LOWER OHIO RIVER
VALLEY WILL MOVE NORTHEAST TONIGHT SPREADING SHOWERS AND POSSIBLY
A FEW EMBEDDED THUNDERSTORMS ACROSS THE FORECAST AREA. TIMING HAS
BEEN A LITTLE TRICKY AS THE UPPER LOW TRANSITIONS TO AN OPEN
WAVE...BUT THE BEST CHANCE OF RAIN AND ANY ASSOCIATED RESTRICTIONS
WILL BE LATE IN THE OVERNIGHT AND EARLY TUESDAY MORNING. EXPECTING
LINGERING SHOWERS AND POSSIBLY THUNDERSTORMS BEHIND THE MAIN WAVE
THROUGH TUESDAY...ALTHOUGH RESTRICTIONS SHOULD REMAIN FAIRLY
LIMITED.
TAX
OUTLOOK...MONDAY NIGHT THROUGH FRIDAY...
THE NEXT CHANCE FOR GENERAL RESTRICTIONS IS EXPECTED WITH A LATE
WEDNESDAY/THURSDAY COLD FRONT APPROACH AND PASSAGE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
702 PM EDT MON AUG 17 2015
.AVIATION...
WIDELY SCATTERED SHRAS/TSRAS WILL FADE AFTER 01Z WITH LOSS OF
DAYTIME HEATING. 4-6SM PATCHY BR WILL ONCE AGAIN BE POSSIBLE LATE
TONIGHT GIVEN HUMID AIRMASS AND LIGHT WINDS. DIURNAL CU WILL BEGIN
SCT MIDDAY TUESDAY WITH PERIODS OF BKN BY MID/LATE AFTERNOON AS A
FEW SHRAS OR TSRAS BEGIN TO DOT THE AREA. WINDS WILL REMAIN LIGHT
OUTSIDE OF STORMS AND GRADUALLY BACK TO SE BY LATE IN THE FORECAST.
FOR DTW...ISOLATED SHRA/TSRA WILL REMAIN POSSIBLE UNTIL ABOUT 01Z
WITH SCT DECK AOB 5KFT. SIMILAR SETUP TUESDAY AFTERNOON WITH CU
AROUND 3500 FEET TRENDING FROM SCT TO BKN DURING THE AFTERNOON.
//DTW THRESHOLD PROBABILITIES...
* LOW FOR CEILING AOB 5KFT THIS EVENING.
* LOW FOR THUNDERSTORMS THROUGH 01Z.
&&
.PREV DISCUSSION...ISSUED 350 PM EDT MON AUG 17 2015
SHORT TERM...THROUGH TONIGHT
WELL-DEFINED UPPER WAVE PER WATER VAPOR IMAGERY WILL TRACK FROM THE
ILLINOIS/INDIANA BORDER UP INTO SOUTHERN LOWER MICHIGAN TONIGHT AS
WESTERLY WINDS ALOFT STRENGTHEN IN RESPONSE TO AN UPPER TROUGH
DIGGING INTO THE NORTHERN ROCKIES/PLAINS. THE FRONTAL BOUNDARY OVER
NORTHERN MICHIGAN IS NOT EXPECTED TO MAKE TOO MUCH SOUTHWARD
PROGRESS TONIGHT...ONLY DROPPING A LITTLE FURTHER INTO NORTHERN
LOWER MICHIGAN...WITH ITS SLOWING ALSO A RESULT OF THE DEEPENING
TROUGH.
MOISTURE ADVECTION INTO SOUTHEAST MICHIGAN STILL LOOKS BEST AFTER
21Z. MOISTURE PLUME CAN BE SEEN ON WATER VAPOR LIFTING IN AHEAD OF
THE UPPER WAVE ATTM. PW VALUES WERE ALREADY FAIRLY HIGH ON THE 12Z
DTX RAOB...AND ARE FORECAST BY NAM/GFS TO RISE TO AROUND 1.7 INCHES
BY 00Z. FORCING WILL BE THE STRONGEST AS THE UPPER WAVE NEARS THE
MICHIGAN BORDER THIS EVENING AND THEN TRACKS OVERHEAD OVERNIGHT.
UNTIL THEN...SHOWERS/STORMS HAVE BEEN FIRING OVER THE FAR SOUTHERN
PART OF THE STATE WHERE THETA-E ADVECTION HAS BEEN STRONGER. EXPECT
SCATTERED SHOWERS/TSTORMS TO CONTINUE DEVELOPING THROUGH THE
EVENING...INCREASING IN COVERAGE AS SYNOPTIC FORCING INCREASES AND
TEMPERATURES ALOFT COOL SLIGHTLY AND STEEPEN LAPSE RATES.
THUNDERSTORMS WILL HAVE POTENTIAL TO PRODUCE VERY HEAVY RAINFALL
GIVEN HIGH DEGREE OF MOISTURE...GOOD INSTABILITY (1500-1700 J/KG ML
CAPE) THIS EVENING...AND SLOW STORM MOVEMENT AT ONLY 15 MPH. A FEW
STORMS MAY BECOME A LITTLE STRONG...PRODUCING WIND GUSTS TO 40 MPH.
THIS HAS ALREADY BEEN EVIDENCED BY A STORM THAT FORMED OVER FAR
WESTERN LAKE ERIE EARLIER TODAY...WHEN A 50 DBZ CORE QUICKLY PULSED
UP TO AROUND 21000FT. PAST SEVERAL RUNS OF THE HRRR HAVE HINTED THAT
VERY SMALL INDIVIDUAL CELLS THAT HAVE BEEN DEVELOPING WILL CONGEAL
INTO A LARGER AREA OF LIGHT SHOWERS LATER THIS EVENING AS CLOUD
COVER OVERSPREADS THE AREA AND WE LOSE DAYTIME HEATING.
TEMPERATURES WILL REMAIN FAIRLY WARM TONIGHT AS DEWPOINTS STAY IN
THE 60S AND CLOUD COVER LIMITS RADIATIONAL COOLING. THIS SHOULD KEEP
MIN TEMPS IN THE MID 60S TO NEAR 70.
LONG TERM...
RELATIVELY MOIST AIRMASS /PWAT VALUES 1.5-1.75 IN/ WILL LINGER OVER
THE GREAT LAKES ON TUESDAY. DISORGANIZED PATTERN MAKES IT HARD TO
IDENTIFY A GOOD LIFTING MECHANISM SO CONFIDENCE IS NOT PARTICULARLY
HIGH ON COVERAGE AND LOCATION OF SHOWERS. WEAKENING SHORTWAVE
TRACKING THROUGH THE STATE IN SOUTHWESTERLY FLOW SHOULD PROVIDE SOME
LIFT. MIDLEVEL MOISTURE LOOKS TO BE A BIT HIGHER OVER MID-MICHIGAN
INCLUDING THE TRI-CITIES AREA SO KEPT LIKELY POPS THERE BUT
GENERALLY BACKED OFF A BIT ON POPS. MEAGER LAPSE RATES WILL LIMIT
INSTABILITY THOUGH A FEW STORMS ARE STILL POSSIBLE WITH
WEAKLY NEGATIVE LIFTED INDICES DURING THE AFTERNOON. TEMPS
ARE EXPECTED TO BE SEVERAL DEGREES COOLER THAN MONDAY WITH THE UPPER
RIDGE HAVING DEPARTED ALONG WITH RELATIVELY HIGH CLOUD FRACTION.
A MILD NIGHT TUESDAY NIGHT WITH A FEW LINGERING SHOWERS POSSIBLE
THOUGH LIKELY WITH LESS COVERAGE THAN DURING THE DAY OWING TO LACK
OF DIURNAL INSTABILITY AND SUBLTE SHORTWAVE UPPER RIDGING.
ON WEDNESDAY...SHORTWAVE ENERGY WILL CONTINUE TO WRAP INTO THE DEEP
TROUGH OVER THE CENTRAL PLAINS AS IT DRIFTS NORTHEASTWARD. AT THE
SURFACE...AN UNSEASONABLY STRONG SURFACE LOW WILL OCCLUDE SOMEWHERE
IN THE VICINITY OF DULUTH MN. STILL VARYING SOLUTIONS WITH RESPECT
TO STRENGTH AND LOCATION OF THIS LOW AND RESULTING TIMING OF COLD
FRONT PUSH ACROSS LOWER MICHIGAN. A SLIGHTLY SLOWER TREND WAS NOTED
IN SOME OF THE 12Z GUIDANCE...WHICH LED TO INCREASING POPS FOR
WEDNESDAY NIGHT. CURRENT THINKING IS THAT THE PEAK TIME FOR PRECIP
IS LATE WEDNESDAY/EARLY WEDNESDAY NIGHT ALONG AND AHEAD OF THE
FRONT. HAVE TO HONOR SEVERE WEATHER THREAT DUE TO THE OVERALL
STRENGTH OF THE SYSTEM. HOWEVER...SIGNIFICANT QUESTION MARKS
EXIST. DEEP-LAYER SHEAR LOOKS TO BE LIMITED IN THE WARM SECTOR...AND
INSTABILITY IS A QUESTION MARK OWING TO WEAK MIDLEVEL LAPSE RATES
AND GOOD CLOUD COVERAGE. A LATER TIMING OF THE FRONT ALSO CASTS
DOUBT UPON SEVERE WEATHER POTENTIAL...ESPECIALLY IF SLOWER TREND
CONTINUES. AS FOR TEMPS...STRONGER SOUTHERLY WINDS ON WEDNESDAY WILL
BUMP UP HIGH TEMPS A COUPLE DEGREES RELATIVE TO TUESDAY.
RAIN SHOWERS WILL COME TO AN END EARLY THURSDAY AS STRONG HIGH
PRESSURE BUILDS INTO THE GREAT LAKES. THIS HIGH WILL STICK AROUND
THROUGH SATURDAY...KEEPING CONDITIONS DRY ACROSS SOUTHEAST MICHIGAN
THROUGH THE FIRST HALF OF THE WEEKEND. THERE IS A BIT OF TIMING
DIFFERENCES FOR THE NEXT COLD FRONT ASSOCIATED WITH A LOW PRESSURE
SYSTEM TRACKING OVER CANADA. SOME MODELS HAVE THE FRONT /AND
THEREFORE RAIN AND THUNDERSTORMS/ PUSHING THROUGH ON SUNDAY WITH
OTHERS NOT HAVING THE FRONT ARRIVING UNTIL EARLY MONDAY MORNING.
WILL HAVE TO KEEP AN EYE ON THIS FEATURE OVER THE NEXT COUPLE DAYS
AS TIMING GETS MORE CERTAIN.
MARINE...
INCREASING MOISTURE FROM THE WEST WILL SUPPORT PERIODS OF SHOWERS
AND THUNDERSTORMS TONIGHT THROUGH WEDNESDAY NIGHT...WITH THE MOST
WIDESPREAD ACTIVITY LIKELY WEDNESDAY AND WEDNESDAY NIGHT. A
DISORGANIZED PRESSURE PATTERN WILL RESULT IN GENERALLY LIGHT WINDS
TONIGHT INTO TUESDAY. EASTERLY/SOUTHEASTERLY FLOW WILL INCREASE
MODESTLY ON WEDNESDAY AS A LOW PRESSURE SYSTEM STRENGTHENS NEAR
DULUTH MN. THIS SYSTEM WILL PUSH A STRONG COLD FRONT THROUGH THE
WATERS LATE WEDNESDAY/WEDNESDAY NIGHT WITH BREEZY SOUTHWESTERLY FLOW
DEVELOPING BEHIND THE FRONT ON THURSDAY.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....DG
SHORT TERM...HLO
LONG TERM....DT/RK
MARINE.......DT
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
443 PM EDT MON AUG 17 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 443 PM EDT MON AUG 17 2015
WATER VAPOR IMAGERY AND RAP ANALYSIS SHOW A BROAD TROF EXTENDING S
INTO THE NRN ROCKIES NRN PLAINS. POTENT LOOKING SHORTWAVE OVER SW MT
WILL GENERATE AN UNUSUALLY STRONG SFC LOW FOR AUG THAT WILL MOVE
ACROSS THE UPPER MISSISSIPPI VALLEY/UPPER GREAT LAKES TUE NIGHT/WED.
SYSTEM ON WATER VAPOR IMAGERY LOOKS STRONGER THAN INDICATED BY
MODELS RIGHT NOW...SO IT WILL BE INTERESTING TO SEE HOW THIS SYSTEM
EVOLVES. TO THE E AND AT THE SFC...COLD FRONT HAS DRIFTED S OF UPPER
MI. WEAKER SHORTWAVES AND RIGHT ENTRANCE OF UPPER JET EXTENDING FROM
NRN MN TO NRN QUEBEC ARE AIDING SHRA/TSTMS FROM IA/SRN MN ENE TO ERN
UPPER MI AND LWR MI. PER LATEST SPC ANALYSIS NRN EDGE OF INSTABILITY
(MLCAPES EXCEEDING 100J/KG) ONLY EXTENDS AS FAR N AS NEAR KMNM AND
THEN E ACROSS NRN LAKE MI. THUS...NO THUNDER HAS BEEN NOTED IN UPPER
MI THIS AFTN.
RIGHT ENTRANCE OF A LESS WELL-DEFINED WITH TIME UPPER JET WILL POSE
SOME RISK FOR GENERATING -SHRA AT TIMES TONIGHT TO THE N OF THE COLD
FRONT WHICH WILL BECOME NEARLY STATIONARY. THERE MAY BE A SUBTLE
SHORTWAVE UPSTREAM AS WELL WHICH COULD AID -SHRA DEVELOPMENT FARTHER
N PER ECWMF...BUT STAYED CLOSE TO THE MULTI-MODEL CONSENSUS IN
CARRYING SCHC POPS FOR AT LEAST SOME PORTION OF THE NIGHT OVER
ROUGHLY THE SE HALF OF THE FCST AREA. CHC POPS WERE CONFINED TO THE
FAR SCNTRL...AND ALSO SE CLOSE TO LAKE MI THIS EVENING. NOT
EXPECTING ANY TSTMS. MAY SEE SOME PATCHY FOG OVERNIGHT.
ON TUE...SFC LOW PRES ORGANIZES OVER THE PLAINS AND REACHES NW IA
LATE IN THE DAY IN RESPONSE TO THE STRONG SHORTWAVE MOVING OUT OVER
THE PLAINS. STRENGTHENING DEEP LAYER FORCING AND STRONG MOISTURE
TRANSPORT AHEAD OF FEATURE WILL SPREAD OVER MN AND THEN TOWARD NW
WI/WRN LAKE SUPERIOR/WRN UPPER MI LATE IN THE AFTN...RESULTING IN AN
INCREASING AREA OF MDT/HVY RAIN AND EMBEDDED THUNDER ORGANIZING TO
THE W AND SW. LOOKS LIKE MUCH OF THIS PCPN WILL HOLD OFF UNTIL TUE
NIGHT. AS FRONT TO THE S BEGINS TO MOVE BACK TO THE N AS A WARM
FRONT...PROBABLY CAN`T RULE OUT A FEW -SHRA DEVELOPING N OF THE
FRONT AS WAA BEGINS...BUT AT LEAST RIGHT NOW...POTENTIAL APPEARS
QUITE LOW. ONLY SCHC WILL BE UTILIZED EXCEPT FOR THE W IN THE AFTN
WHERE POPS WILL INCREASE THRU THE CHC CATEGORY.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 332 PM EDT MON AUG 17 2015
A LOW INTENSIFYING ALONG THE MINNESOTA AND IOWA BORDER AT THE START
OF THE PERIOD WILL BRING UNSETTLED WEATHER FOR THE UPPER GREAT
LAKES REGION THROUGH THE FIRST HALF OF THE LONG TERM FORECAST. THIS
LOW WILL BE AROUND 998MB AND WILL BE LIFTING TO THE NORTH TUESDAY
NIGHT INTO WEDNESDAY (WHILE STRENGTHENING TO 993MB) IN RESPONSE TO
A SHORTWAVE ROUNDING THE BASE OF THE UPPER TROUGH IN THE NORTHERN
PLAINS. THERE ARE SOME DIFFERENCES IN THE MODELS ON HOW FAST THIS
LOW (ANOMALOUS FOR MID-LATE AUGUST) WILL MOVE NORTH THROUGH THE
DULUTH AREA AND ACROSS WESTERN LAKE SUPERIOR ON WEDNESDAY...BUT WITH
THE RECENT TRENDS HEADING TOWARDS A SLOWER DEPARTURE FROM LAKE
SUPERIOR...WILL FOLLOW THAT IDEA IN THE FORECAST.
EXPECT A FEW WAVES OF PRECIPITATION TO MOVE THROUGH THE U.P. WITH
THIS LOW...BUT UNFORTUNATELY THE TRACK WILL NOT PROMOTE A
MUCH NEEDED WIDESPREAD AND SOAKING RAIN FOR MOST OF THE AREA. THE
FIRST WAVE WILL ARRIVE LATE TOMORROW AFTERNOON AND INTO TOMORROW
NIGHT AS BROAD MID LEVEL WARM AIR ADVECTION SWEEPS NORTH ACROSS THE
AREA. THE BEST ASCENT WILL BE TO THE WEST-NORTHWEST OF THE AREA AND
TOWARDS THE MINNESOTA ARROWHEAD...BUT THE WESTERN U.P. COULD BE
BRUSHED BY SOME OF THE STRONGER AREAS OF RAIN. OTHERWISE...EXPECT
RAINFALL AMOUNTS TO SLOWLY DIMINISH FROM AROUND AN INCH OVER THE FAR
WEST TO A HALF AN INCH OR LESS TO THE EAST OF NEWBERRY.
THE NEXT WAVE WILL PUSH NORTH-NORTHEAST THROUGH THE CWA ON
WEDNESDAY MORNING AND PRODUCE AN AREA OF SCATTERED/NUMEROUS SHOWERS
AND MAYBE A FEW THUNDERSTORMS AS IT MOVES THROUGH THE AREA. WILL
SHOW A PERIOD OF THUNDER CHANCES ALONG THAT FRONT AS IT MOVES
THROUGH...TIED TO THE LOWER SHOWALTER VALUES AND MUCAPE VALUES
RISING BETWEEN 500-750 J/KG RIGHT ALONG THE FRONT. EFFECTIVE SHEAR
VALUES LOOK TO BE FAIRLY LOW...SO THAT SHOULD ELIMINATE MUCH OF THE
SEVERE THREAT...EXCEPT FOR AREAS RIGHT ALONG THE COLD FRONT WHICH
WILL TRY TO PUSH EFFECTIVE SHEAR VALUES UP TOWARDS 30KTS. AS THIS
FRONT MOVES NORTH THROUGH THE DAY AND THE DRY SLOT MOVES OVER THE
AREA ALOFT...HAVE TRENDED POPS DOWN OVER THE CENTRAL AND EAST
THROUGH THE DAY...WITH ONLY SLIGHT CHANCES IN THE AFTERNOON
(ALTHOUGH THAT MAY BE TOO HIGH). WRAP AROUND RAIN WILL THEN ARRIVE
OVER THE WEST LATE WEDNESDAY AFTERNOON AND CONTINUE INTO WEDNESDAY
NIGHT. EXPECT THE SCATTERED/NUMEROUS SHOWERS TO STAY MORE OVER THE
WESTERN U.P. BUT DID SPREAD CHANCES EAST OVERNIGHT INTO THURSDAY FOR
MUCH OF THE REST OF THE U.P. WINDS WILL ALSO BE ON THE INCREASE
LATE WEDNESDAY NIGHT INTO THURSDAY MORNING BEHIND THE LOW DUE TO
THE COMBINED PRESSURE RISE AND STEEPENING LOW LEVEL LAPSE RATES
TOWARDS 8-9 C/KM BETWEEN THE SURFACE AND 900MB. THAT WILL LIKELY
PRODUCE GUSTS TO 30KTS OVER WESTERN/CENTRAL LAKE SUPERIOR AND
20-30KTS OVER MOST LAND AREAS.
CONDITIONS WILL IMPROVE THURSDAY NIGHT AS A HIGH PRESSURE RIDGE
BUILDS INTO THE AREA. THIS WILL BRING DECREASING CLOUDS AND WINDS
THROUGH THE NIGHT AND SHOULD LEAD TO A NICE DAY ACROSS THE AREA ON
FRIDAY. THE SUNSHINE WILL BRING HIGHS BACK UP TO NORMAL OR SLIGHTLY
ABOVE NORMAL VALUES ON FRIDAY AND EXPECT TEMPERATURES A TOUCH
WARMER ON SATURDAY (AROUND 80) WITH THE SOUTHERLY FLOW.
ANOTHER STRONG UPPER TROUGH WILL MOVE INTO THE NORTHERN PLAINS ON
SATURDAY AND MOVE THROUGH THE AREA SUNDAY INTO SUNDAY NIGHT. WILL
CONTINUE TO SHOW HIGH CHANCE AND LOW END LIKELY POPS AS THAT MOVES
THROUGH THE AREA BEFORE SLOWLY DEPARTING ON MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 137 PM EDT MON AUG 17 2015
DRIER AIR WILL MAKE SOME INROADS INTO THE AREA THIS AFTN BEHIND A
COLD FRONT THAT HAS SLIPPED SE OF UPPER MI. AS A RESULT...EXPECT
KIWD TO BREAK OUT FROM MVFR TO VFR IN THE NEXT COUPLE OF HRS. KCMX
WILL REMAIN VFR. DRYING WILL BE SLOWER AT KSAW...AND THIS SHOULD
LEAD TO MVFR CIGS PREVAILING FOR MUCH OF THE AFTN INTO THE EARLY
EVENING. AFTER A BREAK TO VFR THIS EVENING AT KSAW...MVFR CIGS MAY
RETURN LATE TONIGHT/TUE MORNING UNDER LIGHT UPSLOPE FLOW OFF LAKE
SUPERIOR. KIWD/KCMX SHOULD REMAIN VFR...THOUGH THERE IS A LOW
POTENTIAL FOR FOG DEVELOPMENT LATE TONIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 443 PM EDT MON AUG 17 2015
HIGH PRES STRETCHING FROM SOUTHERN MANITOBA THROUGH JAMES BAY WILL
EXTEND A RIDGE INTO THE UPPER LAKES THRU TUE MORNING...RESULTING IN
LIGHT WINDS UNDER 15KT ACROSS LAKE SUPERIOR THRU TUE MORNING.
THEN...AS LOW PRES ORGANIZES AND STRENGTHENS OVER THE PLAINS
TUE...NE WINDS WILL BEGIN TO RAMP UP...ESPECIALLY OVER WRN LAKE
SUPERIOR WHERE GUSTS SHOULD REACH 25-30KT LATE AFTN/EARLY EVENING.
THIS LOW WILL BECOME UNSEASONABLY DEEP FOR AUG AS IT LIFTS ACROSS
FAR WRN LAKE SUPERIOR WED AFTN. 20-30KT WINDS ARE EXPECTED OVER MUCH
OF THE LAKE TUE NIGHT INTO WED. MAY SEE GALE FORCE GUSTS OVER FAR
WRN LAKE SUPERIOR IN THE NE WINDS AHEAD OF THE LOW TUE NIGHT AND
THEN IN THE WESTERLY WINDS ACROSS MAINLY CENTRAL LAKE SUPERIOR ON
THU AS THE LOW LIFTS N OF THE AREA. WINDS WILL DIMINISH TO UNDER
20KT FRI...AND THEN BEGIN TO INCREASE AGAIN ON SAT AHEAD OF THE NEXT
COLD FRONT MOVING OUT ACROSS THE PLAINS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
350 PM EDT MON AUG 17 2015
.SHORT TERM...THROUGH TONIGHT
WELL-DEFINED UPPER WAVE PER WATER VAPOR IMAGERY WILL TRACK FROM THE
ILLINOIS/INDIANA BORDER UP INTO SOUTHERN LOWER MICHIGAN TONIGHT AS
WESTERLY WINDS ALOFT STRENGTHEN IN RESPONSE TO AN UPPER TROUGH
DIGGING INTO THE NORTHERN ROCKIES/PLAINS. THE FRONTAL BOUNDARY OVER
NORTHERN MICHIGAN IS NOT EXPECTED TO MAKE TOO MUCH SOUTHWARD
PROGRESS TONIGHT...ONLY DROPPING A LITTLE FURTHER INTO NORTHERN
LOWER MICHIGAN...WITH ITS SLOWING ALSO A RESULT OF THE DEEPENING
TROUGH.
MOISTURE ADVECTION INTO SOUTHEAST MICHIGAN STILL LOOKS BEST AFTER
21Z. MOISTURE PLUME CAN BE SEEN ON WATER VAPOR LIFTING IN AHEAD OF
THE UPPER WAVE ATTM. PW VALUES WERE ALREADY FAIRLY HIGH ON THE 12Z
DTX RAOB...AND ARE FORECAST BY NAM/GFS TO RISE TO AROUND 1.7 INCHES
BY 00Z. FORCING WILL BE THE STRONGEST AS THE UPPER WAVE NEARS THE
MICHIGAN BORDER THIS EVENING AND THEN TRACKS OVERHEAD OVERNIGHT.
UNTIL THEN...SHOWERS/STORMS HAVE BEEN FIRING OVER THE FAR SOUTHERN
PART OF THE STATE WHERE THETA-E ADVECTION HAS BEEN STRONGER. EXPECT
SCATTERED SHOWERS/TSTORMS TO CONTINUE DEVELOPING THROUGH THE
EVENING...INCREASING IN COVERAGE AS SYNOPTIC FORCING INCREASES AND
TEMPERATURES ALOFT COOL SLIGHTLY AND STEEPEN LAPSE RATES.
THUNDERSTORMS WILL HAVE POTENTIAL TO PRODUCE VERY HEAVY RAINFALL
GIVEN HIGH DEGREE OF MOISTURE...GOOD INSTABILITY (1500-1700 J/KG ML
CAPE) THIS EVENING...AND SLOW STORM MOVEMENT AT ONLY 15 MPH. A FEW
STORMS MAY BECOME A LITTLE STRONG...PRODUCING WIND GUSTS TO 40 MPH.
THIS HAS ALREADY BEEN EVIDENCED BY A STORM THAT FORMED OVER FAR
WESTERN LAKE ERIE EARLIER TODAY...WHEN A 50 DBZ CORE QUICKLY PULSED
UP TO AROUND 21000FT. PAST SEVERAL RUNS OF THE HRRR HAVE HINTED THAT
VERY SMALL INDIVIDUAL CELLS THAT HAVE BEEN DEVELOPING WILL CONGEAL
INTO A LARGER AREA OF LIGHT SHOWERS LATER THIS EVENING AS CLOUD
COVER OVERSPREADS THE AREA AND WE LOSE DAYTIME HEATING.
TEMPERATURES WILL REMAIN FAIRLY WARM TONIGHT AS DEWPOINTS STAY IN
THE 60S AND CLOUD COVER LIMITS RADIATIONAL COOLING. THIS SHOULD KEEP
MIN TEMPS IN THE MID 60S TO NEAR 70.
&&
.LONG TERM...
RELATIVELY MOIST AIRMASS /PWAT VALUES 1.5-1.75 IN/ WILL LINGER OVER
THE GREAT LAKES ON TUESDAY. DISORGANIZED PATTERN MAKES IT HARD TO
IDENTIFY A GOOD LIFTING MECHANISM SO CONFIDENCE IS NOT PARTICULARLY
HIGH ON COVERAGE AND LOCATION OF SHOWERS. WEAKENING SHORTWAVE
TRACKING THROUGH THE STATE IN SOUTHWESTERLY FLOW SHOULD PROVIDE SOME
LIFT. MIDLEVEL MOISTURE LOOKS TO BE A BIT HIGHER OVER MID-MICHIGAN
INCLUDING THE TRI-CITIES AREA SO KEPT LIKELY POPS THERE BUT
GENERALLY BACKED OFF A BIT ON POPS. MEAGER LAPSE RATES WILL LIMIT
INSTABILITY THOUGH A FEW STORMS ARE STILL POSSIBLE WITH
WEAKLY NEGATIVE LIFTED INDICES DURING THE AFTERNOON. TEMPS
ARE EXPECTED TO BE SEVERAL DEGREES COOLER THAN MONDAY WITH THE UPPER
RIDGE HAVING DEPARTED ALONG WITH RELATIVELY HIGH CLOUD FRACTION.
A MILD NIGHT TUESDAY NIGHT WITH A FEW LINGERING SHOWERS POSSIBLE
THOUGH LIKELY WITH LESS COVERAGE THAN DURING THE DAY OWING TO LACK
OF DIURNAL INSTABILITY AND SUBLTE SHORTWAVE UPPER RIDGING.
ON WEDNESDAY...SHORTWAVE ENERGY WILL CONTINUE TO WRAP INTO THE DEEP
TROUGH OVER THE CENTRAL PLAINS AS IT DRIFTS NORTHEASTWARD. AT THE
SURFACE...AN UNSEASONABLY STRONG SURFACE LOW WILL OCCLUDE SOMEWHERE
IN THE VICINITY OF DULUTH MN. STILL VARYING SOLUTIONS WITH RESPECT
TO STRENGTH AND LOCATION OF THIS LOW AND RESULTING TIMING OF COLD
FRONT PUSH ACROSS LOWER MICHIGAN. A SLIGHTLY SLOWER TREND WAS NOTED
IN SOME OF THE 12Z GUIDANCE...WHICH LED TO INCREASING POPS FOR
WEDNESDAY NIGHT. CURRENT THINKING IS THAT THE PEAK TIME FOR PRECIP
IS LATE WEDNESDAY/EARLY WEDNESDAY NIGHT ALONG AND AHEAD OF THE
FRONT. HAVE TO HONOR SEVERE WEATHER THREAT DUE TO THE OVERALL
STRENGTH OF THE SYSTEM. HOWEVER...SIGNIFICANT QUESTION MARKS
EXIST. DEEP-LAYER SHEAR LOOKS TO BE LIMITED IN THE WARM SECTOR...AND
INSTABILITY IS A QUESTION MARK OWING TO WEAK MIDLEVEL LAPSE RATES
AND GOOD CLOUD COVERAGE. A LATER TIMING OF THE FRONT ALSO CASTS
DOUBT UPON SEVERE WEATHER POTENTIAL...ESPECIALLY IF SLOWER TREND
CONTINUES. AS FOR TEMPS...STRONGER SOUTHERLY WINDS ON WEDNESDAY WILL
BUMP UP HIGH TEMPS A COUPLE DEGREES RELATIVE TO TUESDAY.
RAIN SHOWERS WILL COME TO AN END EARLY THURSDAY AS STRONG HIGH
PRESSURE BUILDS INTO THE GREAT LAKES. THIS HIGH WILL STICK AROUND
THROUGH SATURDAY...KEEPING CONDITIONS DRY ACROSS SOUTHEAST MICHIGAN
THROUGH THE FIRST HALF OF THE WEEKEND. THERE IS A BIT OF TIMING
DIFFERENCES FOR THE NEXT COLD FRONT ASSOCIATED WITH A LOW PRESSURE
SYSTEM TRACKING OVER CANADA. SOME MODELS HAVE THE FRONT /AND
THEREFORE RAIN AND THUNDERSTORMS/ PUSHING THROUGH ON SUNDAY WITH
OTHERS NOT HAVING THE FRONT ARRIVING UNTIL EARLY MONDAY MORNING.
WILL HAVE TO KEEP AN EYE ON THIS FEATURE OVER THE NEXT COUPLE DAYS
AS TIMING GETS MORE CERTAIN.
&&
.MARINE...
INCREASING MOISTURE FROM THE WEST WILL SUPPORT PERIODS OF SHOWERS
AND THUNDERSTORMS TONIGHT THROUGH WEDNESDAY NIGHT...WITH THE MOST
WIDESPREAD ACTIVITY LIKELY WEDNESDAY AND WEDNESDAY NIGHT. A
DISORGANIZED PRESSURE PATTERN WILL RESULT IN GENERALLY LIGHT WINDS
TONIGHT INTO TUESDAY. EASTERLY/SOUTHEASTERLY FLOW WILL INCREASE
MODESTLY ON WEDNESDAY AS A LOW PRESSURE SYSTEM STRENGTHENS NEAR
DULUTH MN. THIS SYSTEM WILL PUSH A STRONG COLD FRONT THROUGH THE
WATERS LATE WEDNESDAY/WEDNESDAY NIGHT WITH BREEZY SOUTHWESTERLY FLOW
DEVELOPING BEHIND THE FRONT ON THURSDAY.
&&
.AVIATION...ISSUED 208 PM EDT MON AUG 17 2015
CU WILL CONTINUE TO FILL IN...WITH 3500-4500FT CEILINGS DEVELOPING
BETWEEN 19-21Z. SHOWERS AND THUNDERSTORMS WILL ALSO CONTINUE TO
DEVELOP...BECOMING MORE NUMEROUS THROUGH THE AFTERNOON AND EVENING
AS AN UPPER LEVEL DISTURBANCE TRACKS FROM INDIANA TO LOWER MICHIGAN.
MID AND HIGH CLOUDS WILL REMAIN AROUND THROUGH MUCH OF THE
NIGHT...THINNING OUT TOWARDS SUNRISE. THE CLEARING AND LIGHT WINDS
MAY ALLOW SOME LIGHT MVFR FOG TO FILL IN AS LOW-LEVEL
MOISTURE REMAINS IN PLACE.
FOR DTW...3500-4500 CEILINGS WILL CONTINUE TO FILL IN AND BECOME BKN
AT 19-20Z. BEST POTENTIAL FOR SHOWERS AND THUNDERSTORMS WILL BE
BETWEEN 20Z AND 00Z.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM FOR CEILING 5000 FT OR LESS DURING AFTERNOON AND EVENING.
* LOW FOR THUNDERSTORMS DURING LATE AFTERNOON AND EARLY EVENING.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MICHIGAN WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...HLO
LONG TERM....DT/RK
MARINE.......DT
AVIATION.....HLO
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
333 PM EDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1110 AM EDT MON AUG 17 2015
500 MB SHORTWAVE TROUGH MOVING FROM NE IOWA INTO WISCONSIN, IS
PRODUCING SHOWERS ALONG A COLD FRONT THAT STRETCHES FROM AROUND
CYXZ (WAWA) TO NEAR KLSE. THE NORTHERN END HAS DIMINISHED OVER THE
LAST FEW HOURS AS THE SYSTEM HAS BIFURCATED SOMEWHAT, BUT WITH THE
500 MB SHORTWAVE, A NEW AREA OF RAIN IS MOVING OUT OF CENTRAL
WISCONSIN AND INTO W AND C UPPER. THIS IS EXPECTED TO CONTINUE
INTO THE AFTERNOON, SO HAVE BUMPED UP THE POPS ALONG THE FRONT FOR
THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN
UPPER MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN
AND UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET
OVER NW ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER
MI. THE AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG
LINGERED OVER THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO
NEAR 40 KNOTS SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN
CWA OVERNIGHT NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCAPE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAIL WITH MAX TEMPS IN
THE LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW
TO THE LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 332 PM EDT MON AUG 17 2015
A LOW INTENSIFYING ALONG THE MINNESOTA AND IOWA BORDER AT THE START
OF THE PERIOD WILL BRING UNSETTLED WEATHER FOR THE UPPER GREAT
LAKES REGION THROUGH THE FIRST HALF OF THE LONG TERM FORECAST. THIS
LOW WILL BE AROUND 998MB AND WILL BE LIFTING TO THE NORTH TUESDAY
NIGHT INTO WEDNESDAY (WHILE STRENGTHENING TO 993MB) IN RESPONSE TO
A SHORTWAVE ROUNDING THE BASE OF THE UPPER TROUGH IN THE NORTHERN
PLAINS. THERE ARE SOME DIFFERENCES IN THE MODELS ON HOW FAST THIS
LOW (ANOMALOUS FOR MID-LATE AUGUST) WILL MOVE NORTH THROUGH THE
DULUTH AREA AND ACROSS WESTERN LAKE SUPERIOR ON WEDNESDAY...BUT WITH
THE RECENT TRENDS HEADING TOWARDS A SLOWER DEPARTURE FROM LAKE
SUPERIOR...WILL FOLLOW THAT IDEA IN THE FORECAST.
EXPECT A FEW WAVES OF PRECIPITATION TO MOVE THROUGH THE U.P. WITH
THIS LOW...BUT UNFORTUNATELY THE TRACK WILL NOT PROMOTE A
MUCH NEEDED WIDESPREAD AND SOAKING RAIN FOR MOST OF THE AREA. THE
FIRST WAVE WILL ARRIVE LATE TOMORROW AFTERNOON AND INTO TOMORROW
NIGHT AS BROAD MID LEVEL WARM AIR ADVECTION SWEEPS NORTH ACROSS THE
AREA. THE BEST ASCENT WILL BE TO THE WEST-NORTHWEST OF THE AREA AND
TOWARDS THE MINNESOTA ARROWHEAD...BUT THE WESTERN U.P. COULD BE
BRUSHED BY SOME OF THE STRONGER AREAS OF RAIN. OTHERWISE...EXPECT
RAINFALL AMOUNTS TO SLOWLY DIMINISH FROM AROUND AN INCH OVER THE FAR
WEST TO A HALF AN INCH OR LESS TO THE EAST OF NEWBERRY.
THE NEXT WAVE WILL PUSH NORTH-NORTHEAST THROUGH THE CWA ON
WEDNESDAY MORNING AND PRODUCE AN AREA OF SCATTERED/NUMEROUS SHOWERS
AND MAYBE A FEW THUNDERSTORMS AS IT MOVES THROUGH THE AREA. WILL
SHOW A PERIOD OF THUNDER CHANCES ALONG THAT FRONT AS IT MOVES
THROUGH...TIED TO THE LOWER SHOWALTER VALUES AND MUCAPE VALUES
RISING BETWEEN 500-750 J/KG RIGHT ALONG THE FRONT. EFFECTIVE SHEAR
VALUES LOOK TO BE FAIRLY LOW...SO THAT SHOULD ELIMINATE MUCH OF THE
SEVERE THREAT...EXCEPT FOR AREAS RIGHT ALONG THE COLD FRONT WHICH
WILL TRY TO PUSH EFFECTIVE SHEAR VALUES UP TOWARDS 30KTS. AS THIS
FRONT MOVES NORTH THROUGH THE DAY AND THE DRY SLOT MOVES OVER THE
AREA ALOFT...HAVE TRENDED POPS DOWN OVER THE CENTRAL AND EAST
THROUGH THE DAY...WITH ONLY SLIGHT CHANCES IN THE AFTERNOON
(ALTHOUGH THAT MAY BE TOO HIGH). WRAP AROUND RAIN WILL THEN ARRIVE
OVER THE WEST LATE WEDNESDAY AFTERNOON AND CONTINUE INTO WEDNESDAY
NIGHT. EXPECT THE SCATTERED/NUMEROUS SHOWERS TO STAY MORE OVER THE
WESTERN U.P. BUT DID SPREAD CHANCES EAST OVERNIGHT INTO THURSDAY FOR
MUCH OF THE REST OF THE U.P. WINDS WILL ALSO BE ON THE INCREASE
LATE WEDNESDAY NIGHT INTO THURSDAY MORNING BEHIND THE LOW DUE TO
THE COMBINED PRESSURE RISE AND STEEPENING LOW LEVEL LAPSE RATES
TOWARDS 8-9 C/KM BETWEEN THE SURFACE AND 900MB. THAT WILL LIKELY
PRODUCE GUSTS TO 30KTS OVER WESTERN/CENTRAL LAKE SUPERIOR AND
20-30KTS OVER MOST LAND AREAS.
CONDITIONS WILL IMPROVE THURSDAY NIGHT AS A HIGH PRESSURE RIDGE
BUILDS INTO THE AREA. THIS WILL BRING DECREASING CLOUDS AND WINDS
THROUGH THE NIGHT AND SHOULD LEAD TO A NICE DAY ACROSS THE AREA ON
FRIDAY. THE SUNSHINE WILL BRING HIGHS BACK UP TO NORMAL OR SLIGHTLY
ABOVE NORMAL VALUES ON FRIDAY AND EXPECT TEMPERATURES A TOUCH
WARMER ON SATURDAY (AROUND 80) WITH THE SOUTHERLY FLOW.
ANOTHER STRONG UPPER TROUGH WILL MOVE INTO THE NORTHERN PLAINS ON
SATURDAY AND MOVE THROUGH THE AREA SUNDAY INTO SUNDAY NIGHT. WILL
CONTINUE TO SHOW HIGH CHANCE AND LOW END LIKELY POPS AS THAT MOVES
THROUGH THE AREA BEFORE SLOWLY DEPARTING ON MONDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 137 PM EDT MON AUG 17 2015
DRIER AIR WILL MAKE SOME INROADS INTO THE AREA THIS AFTN BEHIND A
COLD FRONT THAT HAS SLIPPED SE OF UPPER MI. AS A RESULT...EXPECT
KIWD TO BREAK OUT FROM MVFR TO VFR IN THE NEXT COUPLE OF HRS. KCMX
WILL REMAIN VFR. DRYING WILL BE SLOWER AT KSAW...AND THIS SHOULD
LEAD TO MVFR CIGS PREVAILING FOR MUCH OF THE AFTN INTO THE EARLY
EVENING. AFTER A BREAK TO VFR THIS EVENING AT KSAW...MVFR CIGS MAY
RETURN LATE TONIGHT/TUE MORNING UNDER LIGHT UPSLOPE FLOW OFF LAKE
SUPERIOR. KIWD/KCMX SHOULD REMAIN VFR...THOUGH THERE IS A LOW
POTENTIAL FOR FOG DEVELOPMENT LATE TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EDT MON AUG 17 2015
WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH TONIGHT...THEN
NE WINDS WILL INCREASE TO UP TO 30 KNOTS TUE INTO TUE NIGHT AS A LOW
PRES SYSTEM MOVES INTO THE UPPER MS VALLEY. WINDS MAY TEMPORARILY
DIMINISH WED AS A LOW PRES SYSTEM MOVES TOWARD LAKE SUPERIOR.
HOWEVER...AS THE STRONG LOW DEPARS LATE WED NIGHT INTO THU SOME WRLY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JSL
SHORT TERM...JLB
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
137 PM EDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1110 AM EDT MON AUG 17 2015
500 MB SHORTWAVE TROUGH MOVING FROM NE IOWA INTO WISCONSIN, IS
PRODUCING SHOWERS ALONG A COLD FRONT THAT STRETCHES FROM AROUND
CYXZ (WAWA) TO NEAR KLSE. THE NORTHERN END HAS DIMINISHED OVER THE
LAST FEW HOURS AS THE SYSTEM HAS BIFURCATED SOMEWHAT, BUT WITH THE
500 MB SHORTWAVE, A NEW AREA OF RAIN IS MOVING OUT OF CENTRAL
WISCONSIN AND INTO W AND C UPPER. THIS IS EXPECTED TO CONTINUE
INTO THE AFTERNOON, SO HAVE BUMPED UP THE POPS ALONG THE FRONT FOR
THE NEXT FEW HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 530 AM EDT MON AUG 17 2015
WV IMAGERY AND RAP ANALYSIS INDICATED A BROAD TROUGH FROM HUDSON BAY
INTO THE NRN PLAINS AND A RIDGE OVER THE ERN CONUS RESULTING IN WSW
MID/UPPER LEVEL FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A
COLD FRONT EXTENDED FROM THE SRN END OF JAMES BAY THROUGH ERN
UPPER MI INTO NE WI. A WEAK SHRTWV COMBINED WITH MID LEVEL FGEN
AND UPPER LEVEL DIV WITH THE RIGHT ENTRANCE OF THE 250-300 MB JET
OVER NW ONTARIO SUPPORTED SCT/NMRS SHRA ACROSS CNTRL AND ERN UPPER
MI. THE AXIS OF GREATER INSTABILITY/MUCAPE TO AROUND 1K J/KG
LINGERED OVER THE SE CWA AND IN COMBINATION WITH 0-6KM SHEAR TO
NEAR 40 KNOTS SUPPORTED CLUSTERS OF STRONG/SVR STORMS OVER THE SRN
CWA OVERNIGHT NEAR THE COLD FRONT.
TODAY...EXPECT THAT THE 850-700 MB FRONTAL BOUNDARY WILL LINGER OVER
THE AREA EVEN AS THE SFC FRONT CONTINUES TO SLIDE TO THE SE. AS
ANOTHER WEAK SHORTWAVE MOVES TOWARD THE AREA...SCT SHOWERS ARE
EXPECTED TO CONTINUE OVER THE SE HALF OF UPPER MI. THERE MAY BE JUST
ENOUGH LINGERING MUCAPE FOR SOME TSRA OVER THE FAR SE.
OTHERWISE...MUCH COOLER CONDITIONS WILL PREVAIL WITH MAX TEMPS IN
THE LOWER 70S AND DEWPOINTS DROPPING INTO THE MID AND UPPER 50S NW
TO THE LOWER 60S SE.
TONIGHT...SHOWERS CHANCES...MAINLY OVER THE SOUTH AND EAST WILL
CONTINUE TO DIMINISH WITH THE MAIN FRONTAL BOUNDARY LINGERING
FARTHER TO THE SOUTH.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT MON AUG 17 2015
SEASONABLY COOL WEATHER WILL PREVAIL FOR THE MIDDLE OF THE WEEK
AMIDST RAIN. TEMPS WILL INCH BACK TO ABOVE AVERAGE BY SATURDAY
BEFORE A COLD FRONT BRINGS A CHANCE FOR RAIN AND ANOTHER COOL-DOWN
ON SUNDAY.
TUESDAY...DEEP MID-LEVEL TROUGHING WILL BE ONGOING ACROSS THE
NORTHERN AND CENTRAL PLAINS BY TUESDAY MORNING...WITH A LEE CYCLONE
FORMING OVER THE CENTRAL HIGH PLAINS. MEANWHILE...THE COLD FRONT
THAT CROSSED THE AREA EARLIER TODAY WILL HAVE WASHED OUT ACROSS
NORTHERN WI...WITH THE H7 TO H8 FRONT LINGERING AS FAR NORTH AS THE
SOUTH-CENTRAL CWA. WIDESPREAD WAA AHEAD OF THE DEVELOPING LOW LOOKS
TO HOLD OFF UNTIL TUESDAY NIGHT...THOUGH MID-LEVEL FGEN BECOMES
APPARENT BY THE AFTERNOON. WITH MODELS BEGINNING TO BACK OFF ON THE
SOUTHWARD PUSH OF DEEP DRY AIR BEHIND THE FRONT TODAY...THINK THAT
AT LEAST SOME LIGHT RAIN WILL BE POSSIBLE BY TUESDAY AFTERNOON.
GIVEN THAT WAA/ISENTROPIC LIFT IS STILL MINIMAL...CONTINUED WITH
JUST SLIGHT CHANCES IN THE FORECAST.
TUESDAY NIGHT AND WEDNESDAY...LOW-LEVEL MOISTURE TRANSPORT AND
ISENTROPIC LIFT QUICKLY INCREASE TUESDAY EVENING AS THE SFC LOW
STRENGTHENS AND NEARS. THE MID-LEVEL SHORTWAVE BEGINS TO TAKE ON
MORE OF A NEGATIVE TILT BY THIS TIME...SENDING MUCH OF THE MID-LEVEL
Q-VECTOR CONV NNE ACROSS MN AND WESTERN LAKE SUPERIOR.
ADDITIONALLY...THE LEFT-EXIT OF A STRENGTHENING 110KT UPPER JET
STREAK WILL PASS WEST OF THE CWA. WITH PWATS SURPASSING 1.5 IN...A
BAND OF HEAVY RAIN SHOULD DEVELOP WEST OF THE CWA...POSSIBLY
CLIPPING THE FAR WEST. MEANWHILE...STEADY LIGHT TO MODERATE RAIN
ASSOCIATED WITH THE WAA IS EXPECTED FOR THE REMAINDER OF THE CWA
THROUGH THE NIGHT. DYNAMICS ARE FAVORABLE FOR POSSIBLE THUNDER
ACROSS THE WEST...WHILE MUCAPE OF AROUND 500 J/KG WILL BE ENOUGH FOR
SOME EMBEDDED THUNDER ACROSS THE EAST.
A RATHER PRONOUNCED MID-LEVEL DRY SLOT WILL QUICKLY SPREAD ACROSS
THE CWA FROM THE SW WEDNESDAY MORNING AS THE SFC LOW TRACKS NNE
ACROSS WESTERN LAKE SUPERIOR. STEEPENING MID-LEVEL LAPSE RATES AHEAD
OF THIS DRY SLOT WILL ALLOW FOR SOME EMBEDDED THUNDERSTORMS. SHOWERS
BECOME ISOLATED ACROSS THE CENTRAL UNDER THE DRY SLOT...BUT CONTINUE
FOR THE FAR WEST AND EAST DURING THE AFTERNOON. ALSO...S TO SW WINDS
LOOK TO GET QUITE GUSTY ACROSS THE CENTRAL AND EAST AHEAD OF AND
UNDER THE DRY SLOT.
WEDNESDAY NIGHT AND THURSDAY...WRAP AROUND MOISTURE WILL KEEP RAIN
CHANCES ACROSS MOST OF THE CWA...PARTICULARLY ALONG LAKE THE WEST
WIND BELTS OF LAKE SUPERIOR...THROUGH THURSDAY BEFORE SYNOPTIC
FORCING AND MOISTURE DEPART THURSDAY NIGHT. H8 TEMPS DOWN TO 5C
COMBINED WITH A STRONG GRADIENT FLOW AND RELATIVELY WARM LAKE TEMPS
WILL ALLOW FOR VERY BREEZY WEST WINDS ON THURSDAY. GUSTS TO 40MPH
ACROSS THE KEWEENAW AND WESTERN SHORE ARE NOT OUT OF THE QUESTION.
FRIDAY THROUGH SUNDAY...WEAK MID-LEVEL CYCLONIC FLOW WILL CONTINUE
OVER THE CWA ON FRIDAY...RESULTING IN VERY SMALL CHANCES OF RAIN
WITH ANY SUBTLE EMBEDDED SHORTWAVE. WILL MAINTAIN A DRY FORECAST
GIVEN THE LITTLE CHANCE OF ANYTHING MATERIALIZING. SATURDAY LOOKS TO
BE ANOTHER WARM DAY AS MID-LEVEL RIDGING AND INCREASING H8 TEMPS
BUILD ACROSS THE UPPER GREAT LAKES. TEMPS SHOULD REACH THE 80S FOR
MOST OF THE CWA. MID-LEVEL TROUGHING GLANCING THE NORTHERN HIGH
PLAINS EARLY SATURDAY WILL RESULT IN LOW-PRESSURE DEVELOPMENT ACROSS
THE NORTHERN PLAINS AND SOUTH-CENTRAL CANADA. GUIDANCE SHOWS SOME
DIFFERENCES IN THE TIMING OF AN ASSOCIATED COLD FRONT CROSSING THE
CWA...BUT A ROUND OF SHOWERS AND STORMS SHOULD AFFECT THE AREA
SOMETIME LATE SATURDAY NIGHT THROUGH SUNDAY. EITHER WAY...GUSTY
SOUTHERLY WINDS OVER 25MPH WILL LIKELY OCCUR AHEAD OF THIS FRONT
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 137 PM EDT MON AUG 17 2015
DRIER AIR WILL MAKE SOME INROADS INTO THE AREA THIS AFTN BEHIND A
COLD FRONT THAT HAS SLIPPED SE OF UPPER MI. AS A RESULT...EXPECT
KIWD TO BREAK OUT FROM MVFR TO VFR IN THE NEXT COUPLE OF HRS. KCMX
WILL REMAIN VFR. DRYING WILL BE SLOWER AT KSAW...AND THIS SHOULD
LEAD TO MVFR CIGS PREVAILING FOR MUCH OF THE AFTN INTO THE EARLY
EVENING. AFTER A BREAK TO VFR THIS EVENING AT KSAW...MVFR CIGS MAY
RETURN LATE TONIGHT/TUE MORNING UNDER LIGHT UPSLOPE FLOW OFF LAKE
SUPERIOR. KIWD/KCMX SHOULD REMAIN VFR...THOUGH THERE IS A LOW
POTENTIAL FOR FOG DEVELOPMENT LATE TONIGHT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 534 AM EDT MON AUG 17 2015
WINDS WILL REMAIN AT OR BELOW 20 KNOTS THROUGH TONIGHT...THEN
NE WINDS WILL INCREASE TO UP TO 30 KNOTS TUE INTO TUE NIGHT AS A LOW
PRES SYSTEM MOVES INTO THE UPPER MS VALLEY. WINDS MAY TEMPORARILY
DIMINISH WED AS A LOW PRES SYSTEM MOVES TOWARD LAKE SUPERIOR.
HOWEVER...AS THE STRONG LOW DEPARS LATE WED NIGHT INTO THU SOME WRLY
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JSL
SHORT TERM...JLB
LONG TERM...TK
AVIATION...ROLFSON
MARINE...JLB
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
341 PM MDT MON AUG 17 2015
.SYNOPSIS...
SEVERE THUNDERSTORMS WILL REMAIN POSSIBLE THROUGH THE EVENING
ACROSS MUCH OF NORTHEAST NEW MEXICO. LARGE HAIL AND DAMAGING WINDS
WILL BE THE MAIN THREATS. THEREAFTER...A DRYING TREND WILL
COMMENCE. MUCH FEWER STORMS ARE EXPECTED TUESDAY THROUGH THURSDAY.
A BACK DOOR FRONT ON TUESDAY NIGHT WILL RESULT IN FALL LIKE
TEMPERATURES ON WEDNESDAY ACROSS THE EASTERN PLAINS. LATER IN THE
WEEK...A SLOW INCREASE IN THUNDERSTORM ACTIVITY IS POSSIBLE.
&&
.DISCUSSION...
SEVERE WEATHER REMAINS POSSIBLE THROUGH THIS EVENING ACROSS THE
NORTHEAST QUADRANT OF NM. 35 TO 40KTS OF BULK SHEAR AND CAPE UP TO
2500 J/KG PER LAPS ANALYSIS WILL PROVIDE AN ENVIRONMENT VERY
SUITABLE FOR STORMS TO BECOME SEVERE AS THEY MOVE OFF THE HIGHER
TERRAIN INTO THE NE PLAINS. A JET MAX WILL ALSO AID IN TSTM
DEVELOPMENT AND FOCUS ACTIVITY ACROSS THE NE. LARGE HAIL AND
DAMAGING WIND GUSTS WILL BE THE MAIN THREAT WITH THIS ACTIVITY.
THE LATEST HRRR SHOWS MOST OF THIS INITIAL ROUND OF ACTIVITY
EXITING NM BY MID EVENING...BUT ANOTHER ROUND OF STORMS MAY
DEVELOP LATER THANKS TO OUTFLOW BOUNDARIES MOVING IN FROM SE CO.
THE UPPER LEVEL TROUGH WILL CROSS THE CENTRAL ROCKIES TONIGHT AND
THE ASSOCIATED PACIFIC FRONT WILL SLIDE THROUGH CENTRAL AND
WESTERN NM. MUCH DRIER AIR BEHIND THE TROUGH AND BREEZY WINDS WILL
MIX DOWN TO THE SURFACE...RESULTING IN SOME OF THE LOWEST
DEWPOINTS WE HAVE SEEN ACROSS THE NW SINCE THE SPRING.
MEANWHILE...THE BACK DOOR SEGMENT OF THE FRONT WILL SLIDE DOWN THE
PLAINS. A FEW STORMS MAY DEVELOP ALONG THE FRONT AND ALONG THE
EAST SLOPES OF THE SANGRES...BUT THE DEEP LAYER OF DRIER AIR ALOFT
WILL LIMIT COVERAGE SIGNIFICANTLY. THE FRONT SHOULD PUSH THRU THE
GAPS OF THE CENTRAL MTN CHAIN TUESDAY NIGHT...BUT THE MOISTURE IT
BRINGS WITH IT SHOULD QUICKLY MIX OUT ON WEDNESDAY WITHIN THE RGV.
ON WEDNESDAY...SOME OF THE MOISTURE ACROSS THE PLAINS WILL ALSO
MIX OUT. CONTINUE LOW LEVEL SOUTHEASTERLY FLOW...HOWEVER...MAY
YIELD A STRAY SHOWER OR TSTM ALONG THE CENTRAL MTN CHAIN...BUT
CONFIDENCE IS PRETTY LOW. THE BIGGER STORY WILL BE THE MUCH COOLER
TEMPS ACROSS THE EAST IN THE WAKE OF THE BACK DOOR FRONT. MOST
AREAS WILL STRUGGLE TO REACH 80.
ANOTHER WEAK WAVE LOOKS TO CROSS NM ON THURSDAY...BUT CONTINUED
DRY AIR OVER THE STATE WILL CONTINUE TO LIMIT TSTM ACTIVITY. SE
PORTIONS OF THE CWA MAY BE FAVORED FOR AN ISOLATED STORM WHERE
BETTER LOW LEVEL MOISTURE EXISTS.
CONFIDENCE REMAINS LOW IN THE FORECAST FRIDAY AND BEYOND. MODELS
CONTINUE TO SUGGEST SOME MOISTURE WILL SEEP UP INTO NM AND WE WILL
SEE A GRADUAL INCREASE IN TSTM ACTIVITY. OF MORE CERTAINTY LOOKS
TO BE ANOTHER BACK DOOR COLD FRONT SLIDING DOWN THE PLAINS OVER
THE WEEKEND WHICH WILL HELP TO MOISTEN UP LOW LEVELS...BUT THE
PARENT TROUGH MAY BRING DRIER AIR OVER NORTHERN NM ONCE AGAIN.
STAY TUNED.
34
&&
.FIRE WEATHER...
FAIRLY ACTIVE AND VIGOROUS BATCH OF SHOWERS AND STORMS AS OF MID
AFTN STRETCHING FROM THE SANGRE DE CRISTOS AND NE HIGHLANDS AND
PLAINS SOUTH AND SOUTHWESTWARD TO THE CENTRAL HIGHLANDS AND MID TO
LOWER RIO GRANDE VALLEY. A FEW HAVE ALREADY BECOME SEVERE ACROSS
THE NORTHERN PORTION OF THIS AREA. THIS ACTIVITY WILL EXPAND SOME
ACROSS THE EASTERN PLAINS THROUGH THE EVE. MOST OF THE NW THIRD OF
THE STATE WILL BE DRY THROUGH THE EVENING AND THIS DRYING TREND
WILL EXPAND SOUTH AND EAST OVER THE NEXT 24 TO 48 HOURS IN THE
WAKE OF A SIGNIFICANT AND EARLIER THAN USUAL MID TO UPPER LOW
PRESSURE TROUGH. ACCOMPANYING AND IN THE WAKE OF THE TROUGH WILL
BE A STRENGTHENING NORTHWEST FLOW ALOFT OVER CENTRAL AND NORTHERN
NEW MEXICO THAT WILL USHER THE MUCH DRIER AIR MASS FROM NW TO SE.
WEST AND NW NEAR SFC WINDS WILL BE PERKING UP SIGNIFICANTLY ACROSS
MUCH OF NORTHERN NM TUE IN RESPONSE TO THE INCREASED NW FLOW ALOFT.
SOME SPOTTY AND LOCALIZED CRITICAL FIRE WEATHER CONDITIONS WILL BE
POSSIBLE OVER AREAS MAINLY BETWEEN THE NW PLATEAU AND THE HIGH
TERRAIN OF RIO ARRIBA AND LOS ALAMOS COUNTIES. THESE CONDITIONS ARE
NOT EXPECTED TO BE WIDESPREAD AND GIVEN CURRENT FUEL STATUS AND
LOW/MODERATE FIRE DANGER...FIRE WEATHER HIGHLIGHTS WILL NOT BE
ISSUED. STILL MIN RH WILL REALLY CRATER OCCUR ON TUE. SURFACE DEW
POINTS WILL DROP INTO THE 20S AND 30S ACROSS THE NW THIRD TO
NEARLY HALF OF FCST AREA TUE AFTN.
DAYTIME TEMPS WILL LOWER BY 5 TO 15 DEGREES...THE MOST EAST...WED IN
WAKE OF AN ASSOCIATED PACIFIC FRONT AS WELL AS A BACKDOOR SEGMENT OF
THE FRONTAL SYSTEM. THE LATTER WILL REACH NE AREAS ON TUESDAY...WITH
THE MAIN SOUTHWARD SURGE TUE NIGHT INTO WED. THIS SHOULD BRING AT
LEAST A MODERATE EAST GAP WIND INTO PORTIONS OF THE RIO GRANDE
VALLEY AND THUS DEW POINTS WILL RECOVER EAST OF THE CENTRAL
MOUNTAIN CHAIN AND TO A LESSER DEGREE INTO THE RIO GRANDE VALLEY FOR
WED.
THE WED TO THU PERIOD SHOULD FEATURE LITTLE OR NO THUNDER IN THE
FCST AREA. EXPECT WARMING TEMPERATURES AND SLIGHT MOISTURE INCREASE
FOR LATE WEEK AS HIGH PRESSURE BUILDS AND THE AIR MASS GRADUALLY
RECOVERS. EXCELLENT VENTILATION THE NEXT 3 TO 5 DAYS...EXCEPT THE
EAST HALF ON WED MAY ONLY REACH FAIR TO GOOD LVLS.
43
&&
.AVIATION...
18Z TAF CYCLE
YET ANOTHER ROUND OF SHRA AND TSRA DEVELOPING AS OF THIS WRITING
ACROSS FAR NORTHERN NM AND THIS ACTIVITY WILL DEVELOP TO THE EAST
AND SE AS THE AFTN PROGRESSES WITH SOME ISOLATED TO SCT DEVELOPMENT
MAINLY E AND SOUTH OF A LINE FROM GRANTS TO THE NW CORNER OF
CATRON COUNTY. SOME STORMS LIKELY TO BECOME STRONG TO SEVERE
ACROSS NE AND E CENTRAL NM LATER THIS AFTN INTO THE EVE WITH A FEW
STRONG STORMS ALSO POSSIBLE REMAINDER OF N CENTRAL AND EASTERN NM.
THESE STRONGER TO SEVERE STORMS MAY PRODUCE BRIEF MVFR CIGS AND
VSBY...ALONG WITH BRIEF MT OBSCURATIONS...HAIL AND WIND GUSTS
BETWEEN 40 AND 55 KTS. DRIER ACROSS ROUGHLY NW THIRD OF NM WITH
ONLY ISOLATED -TSRA COVERAGE. TSRA INTENSITY AND COVERAGE TO
DIMINISH SOME LATE TONIGHT.
43
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 60 92 53 89 / 5 0 5 0
DULCE........................... 50 86 45 82 / 10 10 5 0
CUBA............................ 54 84 52 76 / 10 5 5 0
GALLUP.......................... 54 91 51 88 / 0 0 5 0
EL MORRO........................ 53 86 50 84 / 5 0 5 0
GRANTS.......................... 55 89 51 86 / 0 0 5 0
QUEMADO......................... 56 87 52 85 / 5 5 5 0
GLENWOOD........................ 59 89 56 89 / 10 5 10 0
CHAMA........................... 46 79 43 76 / 10 10 5 0
LOS ALAMOS...................... 60 86 56 78 / 10 5 5 0
PECOS........................... 56 84 54 74 / 30 10 10 10
CERRO/QUESTA.................... 53 78 48 75 / 20 20 10 0
RED RIVER....................... 45 73 43 67 / 30 30 20 10
ANGEL FIRE...................... 47 73 43 66 / 40 30 20 10
TAOS............................ 50 82 49 75 / 10 20 10 0
MORA............................ 54 79 51 71 / 40 20 20 10
ESPANOLA........................ 58 90 56 83 / 10 10 5 0
SANTA FE........................ 61 86 57 80 / 20 10 5 5
SANTA FE AIRPORT................ 59 91 58 83 / 10 5 5 0
ALBUQUERQUE FOOTHILLS........... 66 93 61 86 / 5 0 5 0
ALBUQUERQUE HEIGHTS............. 68 96 64 88 / 0 0 5 0
ALBUQUERQUE VALLEY.............. 65 97 61 90 / 0 0 5 0
ALBUQUERQUE WEST MESA........... 66 96 63 89 / 0 0 5 0
LOS LUNAS....................... 64 97 61 90 / 5 0 5 0
RIO RANCHO...................... 66 97 62 89 / 5 0 5 0
SOCORRO......................... 67 100 64 97 / 5 0 5 0
SANDIA PARK/CEDAR CREST......... 59 89 57 80 / 10 0 5 10
TIJERAS......................... 60 91 56 84 / 10 0 5 0
MORIARTY/ESTANCIA............... 55 91 53 84 / 10 5 5 5
CLINES CORNERS.................. 59 87 54 77 / 20 10 10 10
GRAN QUIVIRA.................... 61 90 57 85 / 10 0 5 5
CARRIZOZO....................... 64 95 62 89 / 10 5 10 5
RUIDOSO......................... 61 83 57 77 / 30 10 20 20
CAPULIN......................... 57 78 51 72 / 70 20 30 5
RATON........................... 55 82 52 74 / 50 30 30 5
SPRINGER........................ 57 85 55 73 / 50 30 30 5
LAS VEGAS....................... 56 86 52 73 / 40 30 20 10
CLAYTON......................... 62 82 53 73 / 60 20 20 5
ROY............................. 60 82 55 69 / 60 30 20 5
CONCHAS......................... 66 91 59 74 / 60 20 20 5
SANTA ROSA...................... 64 94 59 78 / 50 20 20 5
TUCUMCARI....................... 66 91 60 77 / 60 20 20 5
CLOVIS.......................... 64 92 60 77 / 30 30 30 5
PORTALES........................ 65 93 60 77 / 30 30 30 5
FORT SUMNER..................... 67 95 62 75 / 40 20 20 5
ROSWELL......................... 69 101 66 84 / 20 10 20 5
PICACHO......................... 65 96 62 83 / 30 10 20 10
ELK............................. 63 89 61 78 / 30 10 20 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
34
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
255 PM CDT MON AUG 17 2015
.SHORT TERM (TONIGHT THROUGH TUESDAY)...
NO MAJOR HIGHLIGHTS THROUGH TUESDAY WITH NEAR NORMAL CONDITIONS
AND LOW END RAIN CHANCES FOR THE COASTAL PLAINS.
WATER VAPOR AND RUC ANALYSIS REVEAL A SHEAR AXIS AND MID TO UPPER
LEVEL LOW ACROSS THE MID MISSISSIPPI VALLEY EXTENDING SOUTHWEST
ALONG THE TEXAS COAST. THIS FEATURE ALONG WITH AFTERNOON
INSTABILITY WILL GOVERN THE WEATHER PATTERN THROUGH
TUESDAY BY KEEPING TEMPERATURES NEAR NORMAL AND ONLY 20-30%
TSTORM CHANCES ALONG THE COAST WHERE THE SEA-BREEZE CONVERGENCE
WILL BE MORE ACTIVE. PRECIPITABLE WATER AMOUNTS CURRENTLY RANGE
FROM 1.0" TO 1.6" FROM THE RIO GRANDE VALLEY TOWARDS THE COASTAL
PLAINS. THESE VALUES ARE ABOUT 0.5 TO 1 STANDARD DEVIATION BELOW
NORMAL AND THUS RESULTING IN LIMITED SHOWER/STORM ACTIVITY ACROSS
A MAJORITY OF THE REGION. THIS PATTERN WILL CONTINUE THROUGH
TOMORROW WITH ONLY LIMITED SHOWERS AND A FEW THUNDERSTORMS ALONG
THE COASTAL PLAINS.
&&
.LONG TERM (WEDNESDAY THROUGH MONDAY)...
THE LOW-LEVEL PATTERN WILL CHANGE UP MID TO LATE WEEK AS A
BOUNDARY APPROACHES THE REGION FROM THE NORTH WITH HIGHER RAIN
CHANCES AND LOWER MAX HIGH TEMPERATURES LIKELY.
BY MID-WEEK...GLOBAL MODELS AGREE THAT A LARGE LONG WAVE TROUGH
WILL DEVELOP OVER THE CENTRAL CONUS AND WITH ADDITIONAL SHORTWAVE
TROUGH SUPPORT OVER NEW MEXICO AND TEXAS...A PSEUDO COLD FRONT
WILL APPROACH THE REGION FROM THE NORTH LATE WEDNESDAY INTO
THURSDAY MORNING. WEDNESDAY WILL REMAIN NEAR NORMAL TEMPERATURE
WISE WITH HIGHS STILL IN THE MID TO UPPER 90S AREA WIDE AND LOWER
RAIN CHANCES OF 20-40% AREA WIDE. RAIN CHANCES WILL INCREASE GOING
THROUGH THE OVERNIGHT INTO THURSDAY MORNING FOR THE HILL COUNTRY
AS THE BOUNDARY APPROACHES BUT THEN LOOKS TO STALL. WITH THE
SHEAR AXIS OVER TOP OF THE FRONT...THIS SET-UP SHOULD PROVIDE
AREAS WITH MORE CLOUDS AND WITH PWATS INCREASING TO 1.4" TO
1.8"...MORE WIDESPREAD RAIN CHANCES OF AT LEAST 50% APPEAR A
NOMINAL ROUTE TO GO FOR THURSDAY AND CONTINUING INTO FRIDAY. 12Z
GFS APPEARS TO HAVE A MESOSCALE FEEDBACK ISSUE BY PRODUCING A QPF
BULLSEYE JUST SOUTH OF THE REGION AS IT CONSOLIDATES THE UPPER LOW
INTO A TIGHTER CLOSED LOW. SINCE THIS IS THE FIRST ADVERTISEMENT
OF THIS EVOLUTION...WILL SIDE MORE WITH CONSISTANCY AND THE EC
WHICH ALSO LINGERS THE MID LEVEL ENERGY OVER THE REGION. THE EXTRA
CLOUDS SHOULD RESULT IN MAX HIGHS BEING REDUCED TO LOW TO MID 90S
BEING QUITE PLAUSIBLE.
OVER THE WEEKEND...RAIN CHANCES LOOK TO DECREASE AS THE FRONT
WASHES OUT AND SHIFTS NORTH WITH A SUBTROPICAL RIDGE SLOWLY
INCREASING ITS INFLUENCE ACROSS THE NORTH GULF.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 98 77 98 76 / 10 10 10 20 50
AUSTIN BERGSTROM INTL AIRPORT 72 97 74 97 74 / 10 10 10 20 50
NEW BRAUNFELS MUNI AIRPORT 75 98 76 99 76 / 10 10 10 20 40
BURNET MUNI AIRPORT 74 97 75 96 74 / 0 - - 20 50
DEL RIO INTL AIRPORT 76 100 77 100 78 / 0 0 - 20 30
GEORGETOWN MUNI AIRPORT 75 98 77 98 75 / 10 10 10 20 50
HONDO MUNI AIRPORT 73 97 74 98 76 / - - - 20 30
SAN MARCOS MUNI AIRPORT 75 97 77 97 76 / 10 10 10 20 40
LA GRANGE - FAYETTE REGIONAL 75 98 78 98 76 / 20 20 20 30 40
SAN ANTONIO INTL AIRPORT 77 97 78 97 78 / 10 - - 20 40
STINSON MUNI AIRPORT 76 99 77 99 78 / 10 10 10 20 30
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...09
SYNOPTIC/GRIDS...ALLEN
PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1235 PM CDT MON AUG 17 2015
.DISCUSSION...UPDATE FOR 18Z AVIATION.
&&
.AVIATION...CONVECTION WILL BE PRIMARY WX THREAT TO AVIATION
INTERESTS THIS AFTN. SCT CONVECTION XPCTD TO CONTINUE TO DVLP
VCNTY KCRP/KVCT/KALI THRU MID AFTN WITH BRIEF MFR/IFR VSBYS LIKELY
IF CONVECTION MOVES OVER TERMINALS. VFR CONDITIONS WILL PREVAIL
AWAY FROM CONVECTION. CONVECTION MAY APPROACH KLRD LATE THIS AFTN
BUT CONFIDENCE IS LOWER IN PRECIP FALLING AT TERMINAL.
OVERNIGHT...CONVECTIVE DEBRIS CI WILL DSIPT THIS EVENING WITH
MAINLY CLEAR SKIES THRU LATE EVENING. OVERNIGHT...PATCHES OF
STRATUS SHOULD DVLP AND MAY BRIEFLY DRIFT OVER TERMINALS WITH MVFR
CONDITIONS. SCT CU FIELD TO THEN REDVLP TUES MRNG. LIGHT VRB WINDS
EARLY THIS AFTN BCMG MORE SERLY AROUND 10 TO 15 KTS AFTER
SEABREEZE PUSHES THROUGH. HOWEVER...WIND SPEEDS MAY BECOME
VARIABLE FOR BRIEF TIMES FROM CONVECTIVE OUTFLOW BOUNDARIES THIS
AFTN.
&&
.PREV DISCUSSION... /ISSUED 1115 AM CDT MON AUG 17 2015/
DISCUSSION...ENOUGH DIURNAL HEATING HAS OCCURRED TO ALLOW FOR
SCATTERED SHOWERS TO DEVELOP ACROSS THE COASTAL COUNTIES LATE THIS
MORNING AND UAH GOES-R EAST CONVECTIVE INITIATION PROBABILITY
IMAGERY INDICATES FURTHER DEVELOPMENT IS LIKELY ACROSS THE COASTAL
BEND BY EARLY AFTERNOON...AND THUS HAVE ADJUSTED POPS ACCORDINGLY.
FARTHER INLAND...CONVECTIVE ACTIVITY WILL LIKELY BE DELAYED UNTIL
MID/LATE AFTERNOON AS CONVECTIVE TEMPS ARE REACHED AND DEEPER
MOISTURE ARRIVES /ALONG WITH BETTER LLVL MOISTURE CONVERGENCE/.
HAVE EXPANDED AREAL COVERAGE OF POPS FARTHER WEST AND INCREASED
POPS A CATEGORY ACROSS MUCH OF THE BRUSH COUNTRY /ESPECIALLY
SOUTHERN BRUSH COUNTRY/ AS LATEST RAP AND 12Z NAM/CMC AND 00Z
ECMWF INDICATE SLIGHTLY BETTER /ALBEIT STILL WEAK/ UPPER LEVEL
SUPPORT MAY EXIST.
AN ISOLATED TROPICAL FUNNEL MAY OCCUR WITH TOWERING CU/CONVECTION
ACROSS THE COASTAL COUNTIES THROUGH EARLY AFTERNOON GIVEN WEAK
LOW LEVEL WIND FIELD /OCCURRENCE WOULD BE GREATER IF LLVL WIND
FIELD WAS A LITTLE MORE EASTERLY/. ALSO INTRODUCED POSSIBILITY OF
AN ISOLATED WATERSPOUT TODAY FOR MARINE AREAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 95 77 94 79 93 / 20 20 20 20 40
VICTORIA 94 75 95 76 94 / 40 20 30 30 50
LAREDO 100 78 101 78 102 / 20 20 10 10 20
ALICE 98 74 97 77 97 / 40 10 20 10 30
ROCKPORT 93 79 91 81 92 / 40 20 30 40 40
COTULLA 99 76 100 76 100 / 20 20 10 10 20
KINGSVILLE 97 75 96 77 95 / 30 10 20 20 30
NAVY CORPUS 91 79 91 81 90 / 20 20 30 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
RH/79...AVIATION
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1115 AM CDT MON AUG 17 2015
.DISCUSSION...ENOUGH DIURNAL HEATING HAS OCCURRED TO ALLOW FOR
SCATTERED SHOWERS TO DEVELOP ACROSS THE COASTAL COUNTIES LATE THIS
MORNING AND UAH GOES-R EAST CONVECTIVE INITIATION PROBABILITY
IMAGERY INDICATES FURTHER DEVELOPMENT IS LIKELY ACROSS THE COASTAL
BEND BY EARLY AFTERNOON...AND THUS HAVE ADJUSTED POPS ACCORDINGLY.
FARTHER INLAND...CONVECTIVE ACTIVITY WILL LIKELY BE DELAYED UNTIL
MID/LATE AFTERNOON AS CONVECTIVE TEMPS ARE REACHED AND DEEPER
MOISTURE ARRIVES /ALONG WITH BETTER LLVL MOISTURE CONVERGENCE/.
HAVE EXPANDED AREAL COVERAGE OF POPS FARTHER WEST AND INCREASED
POPS A CATEGORY ACROSS MUCH OF THE BRUSH COUNTRY /ESPECIALLY
SOUTHERN BRUSH COUNTRY/ AS LATEST RAP AND 12Z NAM/CMC AND 00Z
ECMWF INDICATE SLIGHTLY BETTER /ALBEIT STILL WEAK/ UPPER LEVEL
SUPPORT MAY EXIST.
AN ISOLATED TROPICAL FUNNEL MAY OCCUR WITH TOWERING CU/CONVECTION
ACROSS THE COASTAL COUNTIES THROUGH EARLY AFTERNOON GIVEN WEAK
LOW LEVEL WIND FIELD /OCCURRENCE WOULD BE GREATER IF LLVL WIND
FIELD WAS A LITTLE MORE EASTERLY/. ALSO INTRODUCED POSSIBILITY OF
AN ISOLATED WATERSPOUT TODAY FOR MARINE AREAS.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 95 77 94 79 93 / 20 20 20 20 40
VICTORIA 94 75 95 76 94 / 40 20 30 30 50
LAREDO 100 78 101 78 102 / 20 20 10 10 20
ALICE 98 74 97 77 97 / 40 10 20 10 30
ROCKPORT 93 79 91 81 92 / 40 20 30 40 40
COTULLA 99 76 100 76 100 / 20 20 10 10 20
KINGSVILLE 97 75 96 77 95 / 30 10 20 20 30
NAVY CORPUS 91 79 91 81 90 / 20 20 30 30 40
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
UPDATE...HART/79
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
335 PM CDT MON AUG 17 2015
.SHORT TERM...
.LATE THIS AFTERNOON AND EARLY EVENING...FORECAST CONFIDENCE IS
MEDIUM.
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS CURRENTLY ARE
SHIFTING SLOWLY NORTHEASTWARD ACROSS THE AREA...ALONG AND AHEAD OF A
WEAK COLD FRONT. THE PRECIPITATION WAS BEING FED BY UPPER DIVERGENCE
FROM A RIGHT REAR ENTRANCE REGION OF A 250 MB JET STREAK. THERE WAS
ALSO SOME 700 MB MOISTURE AND CYCLONIC VORTICITY ADVECTION IN THIS
AREA.
THE UPPER DIVERGENCE IS EXPECTED TO SHIFT EASTWARD ACROSS THE AREA
LATE THIS AFTERNOON INTO EARLY EVENING...AS THE SURFACE COLD FRONT
SLOWLY STALLS ACROSS OR JUST SOUTH OF THE AREA. BEST MESOSCALE
MODELS HAVE BEEN THE HRRR AND EXPERIMENTAL HRRR MODELS...WHICH HAVE
BEEN SLOW THEMSELVES TO INITIATE THE CURRENT CONVECTION. THEY HAVE
THIS ACTIVITY SLIDING OFF TO THE EAST OF THE AREA BY EARLY THIS
EVENING. FOLLOWED THIS TREND WITH THE HIGH END POPS INTO EARLY
EVENING.
SMALL HAIL AND GUSTY WINDS TO AROUND 40 MPH ARE MAINLY EXPECTED WITH
THE STRONGER STORMS...AS DEEP LAYER SHEAR AND MID LEVEL LAPSE RATES
REMAIN RATHER WEAK. AN ISOLATED SEVERE STORM IS POSSIBLE...GIVEN
DECENT 0 TO 3 KM AND MEAN LAYER CAPES ACROSS THE AREA.
.REST OF TONIGHT INTO TUESDAY...FORECAST CONFIDENCE IS MEDIUM.
MORE UNCERTAINTY WITH REGARDS TO POPS FOR LATER THIS EVENING INTO
TUESDAY MORNING. FRONTAL BOUNDARY SHOULD STALL ACROSS OR JUST SOUTH
OF THE AREA. 500 MB VORTICITY MAXIMUM DOES SHIFT THROUGH THE AREA
LATER TONIGHT...WHICH MAY BRING SOME UPWARD MOTION. THE MESOSCALE
MODELS TRY TO BRING IN SOME SHOWERS/STORMS FROM THE SOUTHWEST WITH
THIS FEATURE. KEPT CHANCE POPS FOR COLLABORATION SAKE FOR NOW...BUT
IT MAY END UP DRIER THAN FORECAST.
SHOULD SEE FOG AND SOME LOW STRATUS DEVELOP ACROSS THE AREA LATER
THIS EVENING INTO TUESDAY MORNING...WITH LIGHT WINDS AND MOIST LOW
LEVELS. DENSE FOG IS NOT ANTICIPATED...THOUGH COULD SEE IT IN LOW
LYING AREAS AS WINDS ABOVE THE WEAK INVERSION WEAKEN. THIS WILL HAVE
TO BE WATCHED BY LATER SHIFTS.
BETTER POPS RETURN TUESDAY AFTERNOON...AS FRONT BEGINS TO MOVE
NORTHWARD AS A WARM FRONT. ANOTHER 500 MB VORTICITY MAXIMUM
APPROACHES THE AREA LATER IN THE DAY...ALONG WITH AN INCREASING LOW
LEVEL JET. DEEP LAYER SHEAR REMAINS WEAK IN THE AFTERNOON...WITH
MODEST MEAN LAYER CAPES. SO...THINK SEVERE RISK IS MINIMAL IN THE
AFTERNOON PERIOD.
.TUESDAY NIGHT AND WEDNESDAY...FORECAST CONFIDENCE...MEDIUM
THE GFS MOVES THE STRONG MID/UPPER TROUGH INTO THE UPPER
MISSISSIPPI VALLEY WEDNESDAY. THE UPPER FLOW IS DIFFLUENT TUESDAY
NIGHT AHEAD OF THE TROUGH AND APPROACHING JET. AS THE 250 MB
UPPER JET ROUNDS THE BASE OF THE TROUGH AND LIFTS ACROSS WISCONSIN
IT INCREASES TO 115 KNOTS. THE UPPER DIVERGENCE AND 700 MB UPWARD
MOTION IS STRONGEST TUESDAY NIGHT...BUT WEAKER UPWARD MOTION
CONTINUES INTO THE EARLY AFTERNOON OVER SOUTHEAST WISCONSIN. 700
MB LEVELS ARE NEAR SATURATION TUESDAY NIGHT WITH THE MID LEVEL
DRYING WEDNESDAY MORNING. THE FAR SOUTHEAST IS STILL NEAR THE 700
MB MOISTURE INTO THE AFTERNOON. A 40 KNOT 700 MB SPEED MAX PUSHES
INTO THE SOUTHWEST TUESDAY NIGHT...WITH THE 55 KNOT CORE OVER
SOUTHERN WISCONSIN AROUND NOON WEDNESDAY.
THE 850 MB THERMAL RIDGE IS INTO SOUTHERN WISCONSIN LATE TUESDAY
NIGHT AND REMAINS NEAR KENOSHA WEDNESDAY AFTERNOON. COLD AIR
ADVECTION OCCURS OVER SOUTH CENTRAL WISCONSIN WEDNESDAY
MORNING...AND ACROSS THE SOUTHEAST BY NOON. THE RIBBON OF 850 MB
MOISTURE IS ACROSS MOST OF THE FORECAST AREA BY SUNRISE WEDNESDAY
WITH DRYING FROM THE WEST REACHING LAKE MICHIGAN BY NOON.
SHOWERS AND THUNDERSTORMS OCCUR OVER MUCH OF THE AREA TUESDAY
NIGHT AND BECOMES MORE OF A LINE AS THEY STRENGTHEN AGAIN OVER
SOUTHEAST WISCONSIN WEDNESDAY MORNING. BY WEDNESDAY AFTERNOON THE
PRECIPITATION IF ALL TO THE NORTH AND EAST AS THE MID AND THEN LOW
LEVEL DRYING TAKES OVER.
ZERO TO 1 KM CAPE IS AROUND 500 JOULES/KG TUESDAY NIGHT AND NEAR
800 JOULES/KG OVER THE FAR EAST BY MID MORNING. TIMING FOR THE
SEVERE POTENTIAL IS POOR...BUT SOME SEVERE POTENTIAL IS THERE
TUESDAY NIGHT. THE MODELS HAVE TRENDED A LITTLE SLOWER...AND ANY
MORE DELAY WOULD INCREASE THE RISK...OVER THE EAST ON WEDNESDAY.
.WEDNESDAY NIGHT AND THURSDAY...FORECAST CONFIDENCE...MEDIUM
THE GFS BRINGS A CLOSED MID/UPPER LOW NEAR DULUTH WEDNESDAY NIGHT
BEFORE LIFTING INTO SOUTHERN CANADA THURSDAY. BOTH THE 12Z NAM AND
00Z ECMWF IS A LITTLE QUICKER...AND NOT AS STRONG WITH THE LOW.
THE 850/700 MB RH INCREASES OVER SOUTH CENTRAL WISCONSIN EARLY
WEDNESDAY EVENING...AND OVER MUCH OF THE SOUTH WEDNESDAY NIGHT
WITH THE EDGE OF THE HIGHER RH NEAR THE ILLINOIS BORDER AREA.
THE WRAP AROUND PRECIPITATION STAYS NORTHWEST OF THE FORECAST
AREA...BUT THE GFS DOES BRUSH NORTHWEST SAUK COUNTY BRIEFLY
WEDNESDAY NIGHT.
THE 850/700 MB RH LIFTS NORTH DURING THE DAY THURSDAY. WEST
WINDS WILL BE BRISK.
.LONG TERM...
.THURSDAY NIGHT AND FRIDAY...FORECAST CONFIDENCE...MEDIUM
A ZONAL FLOW AGAIN BRIEFLY DEVELOPS IN THE MID/UPPER LEVELS
ACROSS WISCONSIN WITH ANOTHER SHORTWAVE MOVING TOWARD THE NORTHERN
ROCKIES FRIDAY. THE GFS IS A LITTLE SLOWER WITH THIS.
BOTH THE GFS AND ECMWF ARE MAINLY DRY.
.FRIDAY NIGHT AND SATURDAY...FORECAST CONFIDENCE...MEDIUM
THE MID/UPPER TROUGH EXITS THE NORTHERN ROCKIES AND MOVES INTO THE
NORTHERN PLAINS WITH A WEAK RIDGE OVER WISCONSIN.
BOTH THE 12Z GFS AND 00Z ECMWF KEEP A LOW OVER THE PLAINS WITH
SOME PRECIPITATION JUST APPROACHING THE FORECAST AREA.
.SUNDAY...FORECAST CONFIDENCE...MEDIUM
THE SHORTWAVE REACHES THE UPPER MISSISSIPPI VALLEY SUNDAY. THE
GFS IS JUST A LITTLE FARTHER NORTH AND SLOWER WITH THE SHORTWAVE.
THE SURFACE TROUGH MOVES INTO THE UPPER GREAT LAKES ALONG WITH A
BAND OF MODERATE PRECIPITATION WITH A TRAILING COLD FRONT.
.MONDAY...FORECAST CONFIDENCE...MEDIUM
THE SHORTWAVE MOVES ACROSS THE UPPER GREAT LAKES.
THE 00Z ECMWF HAS SOME LIGHT PRECIPITATION WITH THE LINGERING
UPPER LOW...MAINLY NORTH AREAS...WHILE THE GFS IS DRY ON MONDAY AS
HIGH PRESSURE APPROACHES FROM THE PLAINS.
&&
.AVIATION/00Z TAFS/...
A WEAK COLD FRONT WILL STALL AROUND OR JUST SOUTH OF THE AREA LATE
THIS AFTERNOON AND TONIGHT. SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS ARE EXPECTED INTO THE EARLY EVENING HOURS...BEFORE
SHIFTING OFF TO THE EAST. SMALL HAIL AND GUSTS TO 40 MPH ARE
EXPECTED WITH THE STRONGER STORMS...WITH MVFR VISIBILITIES.
ENOUGH LOW LEVEL MOISTURE AND LIGHT WINDS LATER TONIGHT INTO TUESDAY
MORNING SHOULD LEAD TO IFR FOG AND SOME LOW STRATUS DEVELOPMENT
ACROSS THE AREA. KEPT THIS MENTION GOING IN TAFS.
FRONT MOVES NORTHWARD THROUGH AREA TUESDAY AS A WARM FRONT...WHICH
WILL BRING MORE CHANCES FOR SHOWERS AND STORMS. BEST CHANCES WILL BE
LATER IN THE DAY. WILL MENTION VICINITY THUNDER IN TAFS...GIVEN SOME
TIMING/AREAL COVERAGE UNCERTAINTY. SOUTHEAST WINDS SHOULD INCREASE
DURING THE DAY TUESDAY.
&&
.MARINE...
SCATTERED/NUMEROUS SHOWERS/STORMS ARE EXPECTED TO AFFECT THE
NEARSHORE WATERS OF LAKE MICHIGAN INTO THE EARLY EVENING HOURS...AS
A WEAK COLD FRONT MOVES INTO THE AREA. SMALL HAIL AND GUSTY WINDS TO
33 KNOTS ARE POSSIBLE IN THE STRONGER STORMS.
SHOULD SEE FOG DEVELOP ACROSS THE NEARSHORE WATERS OF LAKE MICHIGAN
LATER TONIGHT INTO TUESDAY MORNING...WITH LIGHT WINDS AND A MOIST
AIRMASS OVER THE REGION. NOT EXPECTING WIDESPREAD DENSE FOG AT THIS
TIME...BUT WILL NEED TO BE MONITORED BY LATER SHIFTS.
MORE SHOWERS AND STORMS ARE FORECAST BY TUESDAY AFTERNOON...WITH THE
BEST CHANCES TUESDAY NIGHT INTO EARLY WEDNESDAY...AS STRONG LOW
PRESSURE MOVES THROUGH THE REGION.
A TIGHT PRESSURE GRADIENT ON WEDNESDAY INTO THURSDAY SHOULD LEAD TO
WINDY CONDITIONS ACROSS THE NEARSHORE WATERS. WINDS SHOULD BE
OFFSHORE DURING THIS TIME. GALE FORCE GUSTS MAY BE POSSIBLE AT
TIMES...WITH A SMALL CRAFT ADVISORY LIKELY NEEDED IN LATER
FORECASTS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/TUESDAY AND AVIATION/MARINE...WOOD
TUESDAY NIGHT THROUGH MONDAY...HENTZ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1252 PM CDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1151 AM CDT MON AUG 17 2015
HAVE BEEN UPDATING THE FORECAST WITH LITTLE TWEEKS THROUGH THE
MORNING HOURS. OVERALL...A TOUGH FORECAST TO DETAIL WITH FORCING
REALLY DIMINISHING IN THE MOIST PLUME.
RADAR ECHOS THROUGH THE AREA ARE NEAR AND JUST BEHIND THE FRONT AT
THE SURFACE WHICH IS ALONG A WEST OF KGRB-KDBQ LINE AT 16Z
SHIFTING SLOWLY EAST. INSTABILITY GROWING RAPIDLY ALONG A SHARP
LINE OF CLOUD/SUN IN CENTRAL WI AND SWRN WI. OVER THE LAST 20
MINUTES ECHOS ARE STARTING TO DEVELOP ON THE FRONT. WITH 1500-2000
J/KG MUCAPE AT 16Z AND CONTINUING TO GROW...THINKING THE FRONT
WILL GET MORE AND MORE ACTIVE WITH TSRA AS IT MOVES INTO SRN/ERN
WI TODAY. THIS WILL LEAVE THE FORECAST AREA IN A POST-FRONTAL
MOIST REGIME WITH ANY BUMP FROM FORCING CAUSING SHOWERS. 850 MB
TROUGH LAGS THE SURFACE PER 88D VWP WINDS AND IS STILL IN THE WRN
FORECAST AREA...ALBEIT WEAK CONVERGENCE...IT COULD CAUSE SHOWERS
TO POP UP. TROUGH/FRONT SHOULD LAY UP ACROSS SRN WI/NERN IA BY
LATER TODAY ALMOST E-W.
RAIN/TSRA OVER NWRN IA IS IN RESPONSE TO LOW-LEVEL E-W TROUGHING
AND GOOD LOW-LEVEL CONVERGENCE AHEAD OF A VERY APPARENT SHORTWAVE
TROUGH IN THE GOES WATER VAPOR APPROACHING OMAHA NEB. SO...HAVE
BEGUN THE IDEA THAT THE SHORTWAVE TROUGH WILL APPROACH THE AREA
THIS EVENING AND WORK WITH THE FRONT...ENHANCE LOW-LEVEL
FRONTOGENESIS...TO SPAWN MORE WIDESPREAD RAIN SHOWERS AND ISOLATED
TSRA MAINLY NEAR AND SOUTH OF I-90 AS IT SHIFTS THROUGH FROM
00-09Z. HAVE NOT UPDATED THE FORECAST YET FOR THAT EVOLUTION AS IT
NEEDS TO BE COLLABORATED WITH THE NEIGHBORING OFFICES...BUT REALLY
LIKE THE LATEST HRRR REFLECTIVITY FORECASTS AS GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
THE COLD FRONT EXTENDED FROM NORTH CENTRAL WISCONSIN INTO
NORTHERN KANSAS EARLY THIS MORNING. REGIONAL RADARS INDICATE THE
REMAINING SHOWERS HAVE BECOME ORIENTED ALONG AND JUST BEHIND THE
FRONT WITH THE LARGEST CONCENTRATION MOVING SLOWLY NORTHEAST OUT
OF NORTHERN IOWA. THIS AREA OF SHOWERS IS ASSOCIATED WITH A WEAK
SECONDARY MOISTURE TRANSPORT AXIS THAT THE 17.06Z RAP MOVES
NORTHEAST INTO THE AREA AND THEN STARTS TO WEAKEN IT AROUND 12Z
INTO THE REST OF THE MORNING. THE 17.06Z HRRR SHOWS THESE TRENDS
WELL AND BRINGS IN THE BAND OF RAIN THROUGH ABOUT 12Z AND THEN
SHOWS IT WEAKENING AS THE MORNING PROGRESSES WITH THE WEAKENING
MOISTURE TRANSPORT.
THE FRONT WILL CONTINUE TO WORK SLOWLY SOUTH THROUGH THE REST OF
THE DAY BUT SOME UNCERTAINTY ON JUST HOW MUCH ACTIVITY WILL OCCUR
WITH IT. MOST OF THE HI-RES MESO MODELS SHOW A CONTINUED
DIMINISHING TREND INTO THE EARLY AFTERNOON WITH MAINLY SCATTERED
COVERAGE. WITH NO SHORT WAVE TROUGHS TO PROVIDE ANY DYNAMIC
SUPPORT TODAY...ANY INCREASE IN ACTIVITY WILL HAVE TO BE
THERMODYNAMICALLY DRIVEN. WITH SOME HEATING OCCURRING UNDER THE
CLOUD COVER...THE 17.00Z NAM SUGGESTS THE MU CAPE COULD INCREASE
INTO THE 1000-1500 J/KG RANGE ACROSS THE SOUTH DURING THE
AFTERNOON. THE FRONTOGENESIS IN THE 1000-850 MB LAYER ALSO SHOWS A
DIURNAL INCREASE DURING THE AFTERNOON AND THIS MAY BE ENOUGH TO
MAINTAIN SOME SCATTERED ACTIVITY ALONG THE FRONT.
DIFFERENCES AMONG THE MODELS THEN START TO SHOW UP IN HOW FAR
SOUTH THE FRONT PROGRESSES TONIGHT. THE NAM AND THE MESO MODELS
SUGGEST A GENERAL LULL IN THE ACTIVITY THIS EVENING BUT THEN START
TO BRING THE FRONT BACK LATE TONIGHT AHEAD OF THE NEXT SYSTEM.
WATER VAPOR SATELLITE THIS MORNING SHOWS THIS NEXT SHORT WAVE
TROUGH WAS OVER EASTERN WASHINGTON AND OREGON. THE GENERAL TREND
IN THE MODELS WITH THIS SYSTEM REMAINS THE SAME WITH IT
INTENSIFYING AS IT APPROACHES...FORMING A CLOSED UPPER LEVEL LOW
OVER THE EASTERN DAKOTAS TUESDAY. SOME DIFFERENCES ON HOW STRONG
THE WAVE BECOMES WITH THE 17.00Z GFS CONTINUING ITS TREND OF BEING
THE STRONGEST WITH IT AND ALSO THEN THE SLOWEST TO MOVE IT OUT.
THE UPPER LEVEL LOW AND SHORT WAVE TROUGH SHOULD THEN LIFT
NORTHEAST ACROSS MINNESOTA AND INTO CANADA TUESDAY NIGHT INTO
WEDNESDAY. THE FORCING AHEAD OF THIS WAVE WILL START TO INCREASE
LATE TONIGHT AS HEIGHT FALLS START TO SPREAD OVER THE REGION. THE
FORCING LOOKS TO BE THE STRONGEST TUESDAY NIGHT AS MODERATE PV
ADVECTION IN THE 500-300 MB LAYER MOVES ACROSS WITH THE SHORT WAVE
TROUGH. THE BEST MOISTURE TRANSPORT SHOULD STAY TO THE WEST OF THE
AREA TONIGHT BUT THERE IS SOME SUGGESTION OF A WEAK BRANCH COMING
INTO THE FRONT FOR LATE TONIGHT. THIS MOISTURE TRANSPORT THEN
CONTINUES TO INCREASE THROUGH THE DAY TUESDAY AND LOOKS TO BE
RIGHT INTO THE AREA FOR TUESDAY EVENING. BASED ON THESE SIGNALS
PLAN TO START INCREASING THE RAIN CHANCES LATE TONIGHT ACROSS THE
SOUTH WITH THE CHANCES THEN INCREASING ACROSS THE ENTIRE AREA
TUESDAY. THE HIGHEST RAIN CHANCES SHOULD OCCUR TUESDAY EVENING AS
THE FRONT MOVES BACK INTO THE AREA AS A SURFACE LOW TRACKS FROM
IOWA INTO MINNESOTA. THEN EXPECTING THE DRY SLOT TO START WORKING
IN FROM THE SOUTH FOR LATE TUESDAY NIGHT INTO WEDNESDAY AS THE
ENTIRE SYSTEM LIFTS OFF TO THE NORTH.
QUESTIONS ON JUST HOW MUCH OF A SEVERE THREAT THERE WILL BE WITH
THIS SYSTEM. EXPECTING RAIN TO BE FALLING AHEAD OF THE WARM FRONT
AND THE WARM SECTOR ITSELF TO NOT BE VERY CLEAN. THIS SHOULD LIMIT
THE AMOUNT OF INSTABILITY WITH BOTH THE NAM AND GFS SHOWING LESS
THEN 750 J/KG OF ML CAPE AVAILABLE IN THE WARM SECTOR. WITH THE
GFS BEING THE STRONGEST WITH THE SYSTEM IT PRODUCES THE MOST SHEAR
WITH 30 TO 35 KNOTS IN THE 0-3KM LAYER WHILE THE NAM STRUGGLES TO
GET 20 KNOTS IN HERE IN THE SAME LAYER. COULD SEE SOME STRONGER
STORMS DEVELOP BUT STILL NOT THINKING THERE WOULD BE MUCH IN THE
WAY OF AN ORGANZID SEVERE EVENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
ANY LINGERING RAIN CHANCES FROM THIS SYSTEM SHOULD MAINLY BE
LIMITED TO THE INTERSTATE 94 CORRIDOR FOR WEDNESDAY NIGHT BEFORE
DRY WEATHER SETTLES IN FOR THURSDAY THROUGH FRIDAY. THE RAIN
CHANCES THEN LOOK LIKE THEY WILL RETURN FOR THE UPCOMING WEEKEND.
PRETTY GOOD AGREEMENT BETWEEN THE GFS AND 17.00Z ECMWF OF A COLD
FRONT SWEEPING ACROSS THE REGION SATURDAY AND SATURDAY NIGHT. THE
SHORT WAVE TROUGH WITH THIS SYSTEM LOOKS TO BE PRETTY SIMILAR TO
THE UPCOMING SYSTEM FOR TUESDAY. IT SHOULD COME IN OFF THE
NORTHERN PACIFIC AND INTENSIFY ONCE IT CROSSES THE NORTHERN
ROCKIES BUT IT MAY TRACK SLIGHTLY FARTHER TO THE NORTH ACROSS
NORTH DAKOTA OR EXTREME SOUTHERN CANADA. THIS COULD BRING IN A
DECENT ROUND OF SHOWERS AND STORMS AGAIN AS THE FRONT COMES
ACROSS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1253 PM CDT MON AUG 17 2015
FORECAST CONFIDENCE CONTINUES TO BE LOWER FOR THIS FORECAST
PACKAGE OF THE TAFS. VERY MOIST AIR MASS OVER THE AREA AND WEAK
ELEMENTS CAUSING LIFT MAKE IT A DIFFICULT FORECAST FOR DETAILS.
HAVE GONE WITH A BIT OF DRYING NORTHERLY WIND TODAY TO LIFT THE
CEILINGS FOR A PERIOD THIS AFTERNOON. VFR IS ONLY ABOUT A COUNTY
NORTH OF THE AIRFIELDS. HOWEVER THERE IS A CHANCE THAT SHOWERS
AND AN MVFR DECK WILL ROLL INTO KRST LATER THIS AFTERNOON/EVENING
ASSOCIATED WITH THE WEATHER NOW NEAR KRWF IN SWRN MN. THOSE MVFR
CIGS ARE ALREADY WEST OF KRST.
OTHERWISE...HAVE BEGUN A TREND OF MOISTENING THE LOW-LEVELS
OVERNIGHT TO BRING IN SOME LOWER CEILINGS AND FOG. DEWPOINT
DEPRESSIONS ARE WILL NOT BE MORE THAN 5-8F EARLY THIS
EVENING...PRETTY EASY TO OVERCOME.
&&
.HYDROLOGY...
ISSUED AT 348 AM CDT MON AUG 17 2015
DECENT RAINFALL AMOUNTS ARE EXPECTED WITH THE UPCOMING SYSTEM FROM
LATE TONIGHT THROUGH WEDNESDAY. CURRENTLY EXPECTING RAINFALL
AMOUNTS OF 1 TO 1.5 INCHES OVER THIS SPREAD OUT PERIOD. THESE
AMOUNTS AND THE SOMEWHAT EXTENDED TIME FRAME OVER WHICH THEY ARE
EXPECTED...SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING
PROBLEMS...ESPECIALLY GIVEN THE RECENT DRY CONDITIONS THAT HAVE
DEVELOPED. NOT ANTICIPATING THE NEED FOR ANY HYDROLOGIC HEADLINES
FROM THIS SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...04
LONG TERM...04
AVIATION...BAUMGARDT
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1151 AM CDT MON AUG 17 2015
.UPDATE...
ISSUED AT 1151 AM CDT MON AUG 17 2015
HAVE BEEN UPDATING THE FORECAST WITH LITTLE TWEEKS THROUGH THE
MORNING HOURS. OVERALL...A TOUGH FORECAST TO DETAIL WITH FORCING
REALLY DIMINISHING IN THE MOIST PLUME.
RADAR ECHOS THROUGH THE AREA ARE NEAR AND JUST BEHIND THE FRONT AT
THE SURFACE WHICH IS ALONG A WEST OF KGRB-KDBQ LINE AT 16Z
SHIFTING SLOWLY EAST. INSTABILITY GROWING RAPIDLY ALONG A SHARP
LINE OF CLOUD/SUN IN CENTRAL WI AND SWRN WI. OVER THE LAST 20
MINUTES ECHOS ARE STARTING TO DEVELOP ON THE FRONT. WITH 1500-2000
J/KG MUCAPE AT 16Z AND CONTINUING TO GROW...THINKING THE FRONT
WILL GET MORE AND MORE ACTIVE WITH TSRA AS IT MOVES INTO SRN/ERN
WI TODAY. THIS WILL LEAVE THE FORECAST AREA IN A POST-FRONTAL
MOIST REGIME WITH ANY BUMP FROM FORCING CAUSING SHOWERS. 850 MB
TROUGH LAGS THE SURFACE PETR 88D VWP WINDS AND IS STILL IN THE
WRN FORECAST AREA...ALBEIT WEAK CONVERGENCE...IT COULD CAUSE
SHOWERS TO POP UP. TROUGH/FRONT SHOULD LAY UP ACROSS SRN WI/NERN
IA BY LATER TODAY ALMOST E-W.
RAIN/TSRA OVER NWRN IA IS IN RESPONSE TO LOW-LEVEL E-W TROUGHING
AND GOOD LOW-LEVEL CONVERGENCE AHEAD OF A VERY APPARENT SHORTWAVE
TROUGH IN THE GOES WATER VAPOR APPROACHING OMAHA NEB. SO...HAVE
BEGUN THE IDEA THAT THE SHORTWAVE TROUGH WILL APPROACH THE AREA
THIS EVENING AND WORK WITH THE FRONT...ENHANCE LOW-LEVEL
FRONTOGENESIS...TO SPAWN MORE WIDESPREAD RAIN SHOWERS AND ISOLATED
TSRA MAINLY NEAR AND SOUTH OF I-90 AS IT SHIFTS THROUGH FROM
00-09Z. HAVE NOT UPDATED THE FORECAST YET FOR THAT EVOLUTION AS IT
NEEDS TO BE COLLABORATED WITH THE NEIGHBORING OFFICES...BUT REALLY
LIKE THE LATEST HRRR REFLECTIVITY FORECASTS AS GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
THE COLD FRONT EXTENDED FROM NORTH CENTRAL WISCONSIN INTO
NORTHERN KANSAS EARLY THIS MORNING. REGIONAL RADARS INDICATE THE
REMAINING SHOWERS HAVE BECOME ORIENTED ALONG AND JUST BEHIND THE
FRONT WITH THE LARGEST CONCENTRATION MOVING SLOWLY NORTHEAST OUT
OF NORTHERN IOWA. THIS AREA OF SHOWERS IS ASSOCIATED WITH A WEAK
SECONDARY MOISTURE TRANSPORT AXIS THAT THE 17.06Z RAP MOVES
NORTHEAST INTO THE AREA AND THEN STARTS TO WEAKEN IT AROUND 12Z
INTO THE REST OF THE MORNING. THE 17.06Z HRRR SHOWS THESE TRENDS
WELL AND BRINGS IN THE BAND OF RAIN THROUGH ABOUT 12Z AND THEN
SHOWS IT WEAKENING AS THE MORNING PROGRESSES WITH THE WEAKENING
MOISTURE TRANSPORT.
THE FRONT WILL CONTINUE TO WORK SLOWLY SOUTH THROUGH THE REST OF
THE DAY BUT SOME UNCERTAINTY ON JUST HOW MUCH ACTIVITY WILL OCCUR
WITH IT. MOST OF THE HI-RES MESO MODELS SHOW A CONTINUED
DIMINISHING TREND INTO THE EARLY AFTERNOON WITH MAINLY SCATTERED
COVERAGE. WITH NO SHORT WAVE TROUGHS TO PROVIDE ANY DYNAMIC
SUPPORT TODAY...ANY INCREASE IN ACTIVITY WILL HAVE TO BE
THERMODYNAMICALLY DRIVEN. WITH SOME HEATING OCCURRING UNDER THE
CLOUD COVER...THE 17.00Z NAM SUGGESTS THE MU CAPE COULD INCREASE
INTO THE 1000-1500 J/KG RANGE ACROSS THE SOUTH DURING THE
AFTERNOON. THE FRONTOGENESIS IN THE 1000-850 MB LAYER ALSO SHOWS A
DIURNAL INCREASE DURING THE AFTERNOON AND THIS MAY BE ENOUGH TO
MAINTAIN SOME SCATTERED ACTIVITY ALONG THE FRONT.
DIFFERENCES AMONG THE MODELS THEN START TO SHOW UP IN HOW FAR
SOUTH THE FRONT PROGRESSES TONIGHT. THE NAM AND THE MESO MODELS
SUGGEST A GENERAL LULL IN THE ACTIVITY THIS EVENING BUT THEN START
TO BRING THE FRONT BACK LATE TONIGHT AHEAD OF THE NEXT SYSTEM.
WATER VAPOR SATELLITE THIS MORNING SHOWS THIS NEXT SHORT WAVE
TROUGH WAS OVER EASTERN WASHINGTON AND OREGON. THE GENERAL TREND
IN THE MODELS WITH THIS SYSTEM REMAINS THE SAME WITH IT
INTENSIFYING AS IT APPROACHES...FORMING A CLOSED UPPER LEVEL LOW
OVER THE EASTERN DAKOTAS TUESDAY. SOME DIFFERENCES ON HOW STRONG
THE WAVE BECOMES WITH THE 17.00Z GFS CONTINUING ITS TREND OF BEING
THE STRONGEST WITH IT AND ALSO THEN THE SLOWEST TO MOVE IT OUT.
THE UPPER LEVEL LOW AND SHORT WAVE TROUGH SHOULD THEN LIFT
NORTHEAST ACROSS MINNESOTA AND INTO CANADA TUESDAY NIGHT INTO
WEDNESDAY. THE FORCING AHEAD OF THIS WAVE WILL START TO INCREASE
LATE TONIGHT AS HEIGHT FALLS START TO SPREAD OVER THE REGION. THE
FORCING LOOKS TO BE THE STRONGEST TUESDAY NIGHT AS MODERATE PV
ADVECTION IN THE 500-300 MB LAYER MOVES ACROSS WITH THE SHORT WAVE
TROUGH. THE BEST MOISTURE TRANSPORT SHOULD STAY TO THE WEST OF THE
AREA TONIGHT BUT THERE IS SOME SUGGESTION OF A WEAK BRANCH COMING
INTO THE FRONT FOR LATE TONIGHT. THIS MOISTURE TRANSPORT THEN
CONTINUES TO INCREASE THROUGH THE DAY TUESDAY AND LOOKS TO BE
RIGHT INTO THE AREA FOR TUESDAY EVENING. BASED ON THESE SIGNALS
PLAN TO START INCREASING THE RAIN CHANCES LATE TONIGHT ACROSS THE
SOUTH WITH THE CHANCES THEN INCREASING ACROSS THE ENTIRE AREA
TUESDAY. THE HIGHEST RAIN CHANCES SHOULD OCCUR TUESDAY EVENING AS
THE FRONT MOVES BACK INTO THE AREA AS A SURFACE LOW TRACKS FROM
IOWA INTO MINNESOTA. THEN EXPECTING THE DRY SLOT TO START WORKING
IN FROM THE SOUTH FOR LATE TUESDAY NIGHT INTO WEDNESDAY AS THE
ENTIRE SYSTEM LIFTS OFF TO THE NORTH.
QUESTIONS ON JUST HOW MUCH OF A SEVERE THREAT THERE WILL BE WITH
THIS SYSTEM. EXPECTING RAIN TO BE FALLING AHEAD OF THE WARM FRONT
AND THE WARM SECTOR ITSELF TO NOT BE VERY CLEAN. THIS SHOULD LIMIT
THE AMOUNT OF INSTABILITY WITH BOTH THE NAM AND GFS SHOWING LESS
THEN 750 J/KG OF ML CAPE AVAILABLE IN THE WARM SECTOR. WITH THE
GFS BEING THE STRONGEST WITH THE SYSTEM IT PRODUCES THE MOST SHEAR
WITH 30 TO 35 KNOTS IN THE 0-3KM LAYER WHILE THE NAM STRUGGLES TO
GET 20 KNOTS IN HERE IN THE SAME LAYER. COULD SEE SOME STRONGER
STORMS DEVELOP BUT STILL NOT THINKING THERE WOULD BE MUCH IN THE
WAY OF AN ORGANZID SEVERE EVENT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON AUG 17 2015
ANY LINGERING RAIN CHANCES FROM THIS SYSTEM SHOULD MAINLY BE
LIMITED TO THE INTERSTATE 94 CORRIDOR FOR WEDNESDAY NIGHT BEFORE
DRY WEATHER SETTLES IN FOR THURSDAY THROUGH FRIDAY. THE RAIN
CHANCES THEN LOOK LIKE THEY WILL RETURN FOR THE UPCOMING WEEKEND.
PRETTY GOOD AGREEMENT BETWEEN THE GFS AND 17.00Z ECMWF OF A COLD
FRONT SWEEPING ACROSS THE REGION SATURDAY AND SATURDAY NIGHT. THE
SHORT WAVE TROUGH WITH THIS SYSTEM LOOKS TO BE PRETTY SIMILAR TO
THE UPCOMING SYSTEM FOR TUESDAY. IT SHOULD COME IN OFF THE
NORTHERN PACIFIC AND INTENSIFY ONCE IT CROSSES THE NORTHERN
ROCKIES BUT IT MAY TRACK SLIGHTLY FARTHER TO THE NORTH ACROSS
NORTH DAKOTA OR EXTREME SOUTHERN CANADA. THIS COULD BRING IN A
DECENT ROUND OF SHOWERS AND STORMS AGAIN AS THE FRONT COMES
ACROSS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 659 AM CDT MON AUG 17 2015
SHOWERS AND ISOLATED THUNDERSTORMS WILL EDGE SOUTHEAST ACROSS THE
AREA THIS MORNING ALONG A WEAKENING COLD FRONT WITH PERIODS OF
MVFR TO IFR CONDITIONS POSSIBLE AT TIMES. THIS ACTIVITY WILL
GRADUALLY TAPER OFF AND SHIFT SOUTHEAST OF KRST BY LATE THIS
MORNING AND BY MID TO LATE AFTERNOON AT KLSE. CEILINGS COULD FALL
TO AROUND 400 FT UNDER THE HEAVIER SHOWERS AND THE VISIBILITY MAY
BE REDUCED TO 2 SM OR LESS. IN THE WAKE OF THE FRONT A BRIEF
PERIOD OF MVFR STRATUS IS EXPECTED THEN CEILINGS SHOULD IMPROVE TO
VFR AND STAY THERE THROUGH THE OVERNIGHT HOURS.
&&
.HYDROLOGY...
ISSUED AT 348 AM CDT MON AUG 17 2015
DECENT RAINFALL AMOUNTS ARE EXPECTED WITH THE UPCOMING SYSTEM FROM
LATE TONIGHT THROUGH WEDNESDAY. CURRENTLY EXPECTING RAINFALL
AMOUNTS OF 1 TO 1.5 INCHES OVER THIS SPREAD OUT PERIOD. THESE
AMOUNTS AND THE SOMEWHAT EXTENDED TIME FRAME OVER WHICH THEY ARE
EXPECTED...SHOULD NOT BE ENOUGH TO CAUSE ANY FLOODING
PROBLEMS...ESPECIALLY GIVEN THE RECENT DRY CONDITIONS THAT HAVE
DEVELOPED. NOT ANTICIPATING THE NEED FOR ANY HYDROLOGIC HEADLINES
FROM THIS SYSTEM.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BAUMGARDT
SHORT TERM...04
LONG TERM...04
AVIATION...WETENKAMP
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
235 PM MDT MON AUG 17 2015
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 235 PM MDT MON AUG 17 2015
FORECAST CHALLENGES DEAL WITH A VARIETY OF TOPICS THIS AFTERNOON.
WE HAVE CHANCES FOR SEVERE THUNDERSTORMS EAST OF THE LARAMIE
RANGE...RED FLAG CONCERNS OUT WEST AND THEN THE RETURN OF FOG AND
STRATUS TONIGHT.
CURRENTLY...LATEST VISIBLE IMAGERY SHOWING STRATUS LAYER HANGING
TOUGH GENERALLY ALONG AND SOUTH OF A LINE FROM GLENDO TO ALLIANCE
THIS AFTERNOON. LATEST SPC MESOANALYST PAGE SHOWING A SOLIDLY
CAPPED ENVIRONMENT UNDER THIS STRATUS WITH CONVECTIVE INHIBITION
ANYWHERE FROM -50 J/KG UP BY WHEATLAND TO -300 J/KG OUT BY SIDNEY.
CONVERSE...NIOBRARA COUNTIES IN EAST CENTRAL WYOMING AND THE
NORTHERN PANHANDLE HAS BEGUN TO BREAK OUT WITH TEMPERATURES
CLIMBING INTO THE LOW 70S AS OF 1 PM. IR IMAGERY SHOWING AN UPPER
SHORTWAVE TRACKING INTO SOUTH CENTRAL MONTANA AND NORTH CENTRAL
WYOMING THIS AFTERNOON. NEED TO BE WATCHING OUR NORTHERN COUNTIES
TODAY FOR POSSIBLE SEVERE THUNDERSTORM DEVELOPMENT. LATEST SPC DAY
1 OUTLOOK WAS EXPANDED NORTH TO INCLUDE THIS AREA AS WELL AS
WESTERN SOUTH DAKOTA AND NORTHEASTERN WYOMING. DID REMOVE SEVERE
THUNDERSTORM WORDING FROM OUR SOUTHERN ZONES AS THEY WILL MOST
LIKELY STAY IN STRATUS THROUGH THE AFTERNOON.
DID INTRODUCE SEVERE THUNDERSTORMS ACROSS OUR NORTHERN ZONES FOR
EARLY THIS EVENING. THAT SHORTWAVE MOVES INTO NORTHWESTERN SOUTH
DAKOTA. LATEST HRRR SIMULATED RADAR SHOWING SOME PRETTY STRONG
STORMS DEVELOPING ALONG A SQUALL LINE THAT DEVELOPS AFTER 00Z THAT
COULD PERSIST INTO THE LATE EVENING HOURS. STILL VERY CONDITIONAL
THOUGH AS LATEST MESOANALYSIS PAGE CAPS OFF LOW LEVELS AFTER
SUNSET. WOULD THINK THE ASSOCIATED SURFACE TROUGH/FRONT WITH THE
UPPER SHORTWAVE WOULD BREAK THAT CAP THOUGH.
TO THE WEST...KEPT CURRENT FIRE HEADLINES GOING AS THEY ARE FOR
FWZ 304 AND 306. THEY ARE VERY CLOSE TO VERIFYING RIGHT NOW...SO
RED FLAG WARNINGS ARE ON TRACK. NO CHANGES PLANNED.
THERE IS A BRIEF PERIOD THIS EVENING BEFORE THE SURFACE
FRONT/TROUGH MOVES THROUGH THE SOUTHERN CWFA WHERE WE SEE
SOUTHEASTERLY WINDS. WITH CURRENT STRATUS ALREADY IN PLACE...THINK
THERE IS A PERIOD BETWEEN ABOUT 9 PM AND 3 AM WHERE WE COULD SEE
FOG ONCE AGAIN. ONCE THE SURFACE TROUGH MOVES THROUGH...FAIRLY
STRONG NORTHWEST DOWNSLOPING WINDS SHOULD SCOUR OUT FOG/STRATUS
SHORTLY AFTER 06Z OR SO FROM NORTH TO SOUTH.
KEPT POPS GOING FOR OUR EASTERN ZONES WEDNESDAY AS WRAP-AROUND
ENERGY FROM THE DEPARTING LOW IMPACTS THE PANHANDLE AND MAYBE OUR
EXTREME EASTERN COUNTIES.
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 235 PM MDT MON AUG 17 2015
A GENERALLY DRY AND MILD/WARM PATTERN EXPECTED TO PREVAIL AVER THE
CWA DURING THE PERIOD. TEMPERATURES WILL TURN WARMER THURSDAY AS
DOWNSLOPE FLOW DEVELOPS IN RESPONSE TO LEE TROFFING SETTING UP
OVER THE HIGH PLAINS. THIS WILL CONTINUE THROUGH FRIDAY AHEAD OF A
DIGGING UPPER TROF THAT WILL MOVE INTO THE NRN ROCKYS FRIDAY
NIGHT. THIS WILL PUSH THE NEXT COOL FRONT ACROSS THE CWA SATURDAY
WITH A BIT OF CONVECTION POSSIBLE WITH IT. EC QUICKER THAN THE GFS
WITH THIS SYSTEM BY ABOUT 12 HOURS WITH COULD IMPACT MAX TEMPS FOR
SATURDAY. SUNDAY AND MONDAY DRY AND SEASONAL WITH A BUILDING
UPPER RIDGE OVER THE ROCKY MTNS
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1131 AM MDT MON AUG 17 2015
SFC UPSLOPE FLOW KEEPING MVFR/IFR CIGS IN PLACE OVER MANY AREAS EAST
OF THE LARAMIE RANGES THIS MORNING THOUGH SOME THINNING NOTED OVER
THE NORTHERN PANHANDLE. MAIN PROBLEM WILL BE DETERMINING HOW MUCH
IMPROVEMENT OCCURS THIS AFTERNOON. WITH SFC UPSLOPE FLOW EXPECTED
TO PERSIST WILL FAVOR KEEPING LOW CIGS IN PLACE FOR KCYS TO KSNY
WHILE IMPROVING TO VFR AT KAIA. EXPECT CONDITIONS TO DETERIORATE TO
MVFR/IFR MOST AREAS TONIGHT AS NEXT COLD FRONT PASSES AND REINFORCES
UPSLOPE FLOW WITH AREAS OF RAIN DEVELOPING OVER THE PLAINS AS
WELL.
&&
.FIRE WEATHER...
ISSUED AT 235 PM MDT MON AUG 17 2015
WINDS HAVE BEGUN TO INCREASE OUT ACROSS CARBON COUNTY AND WESTERN
ALBANY COUNTY THIS AFTERNOON. LATEST OBSERVATIONS SHOWING
HUMIDITIES FALLING INTO LOW TEENS AND UPPER SINGLE DIGITS AT 1 PM.
WINDS ARE ON THE INCREASE AS WELL...SO CURRENT FIRE WEATHER
HEADLINES LOOK TO BE ON TRACK. WILL CONTINUE CURRENT RED FLAG
WARNINGS AS THEY ARE AS HEADLINES ARE IN GOOD SHAPE. LOOKING AT
LOW AFTERNOON HUMIDITIES ON A DAILY BASIS WEST OF THE LARAMIE
RANGE THROUGH THE WEEK. FORTUNATELY...WINDS LOOK TO BE WEAK AT
LEAST THROUGH THURSDAY BEFORE ANOTHER LOW PRESSURE SYSTEM
APPROACHES FROM THE WEST. COULD BE LOOKING AT CRITICAL FIRE
WEATHER CONDITIONS FRIDAY INTO SATURDAY AS THIS LOW SLOWLY TRACKS
INTO MONTANA.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...RED FLAG WARNING UNTIL 8 PM MDT THIS EVENING FOR WYZ304-306.
NE...NONE.
&&
$$
SHORT TERM...GCC
LONG TERM...RE
AVIATION...RE
FIRE WEATHER...GCC