Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/02/15
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
845 PM MST SAT AUG 1 2015
&&
.SYNOPSIS...
LINGERING STORM CHANCES THE REST OF TODAY WILL MAINLY AFFECT AREAS
ACROSS HIGHER TERRAIN AREAS OF CENTRAL AND EASTERN ARIZONA WITH A
SLIGHT CHANCE OF A FEW STORMS OVER THE LOWER DESERTS. CONSIDERABLE
DRYING OCCURS STARTING SUNDAY AND INTO THE MIDDLE OF NEXT WEEK WITH
STORM CHANCES CONFINED TO THE HIGHER TERRAIN EAST OF PHOENIX.
TEMPERATURES WILL HOVER NEAR NORMAL OR SLIGHTLY ABOVE THROUGH NEXT
WEEK.
&&
.DISCUSSION... A MUCH QUIETER AFTERNOON/EVENING TODAY THAN WHAT WE
SAW YESTERDAY...ESPECIALLY ACROSS THE LOWER ELEVATIONS OF SOUTH-
CENTRAL AZ. DRY AIR THAT IS BEING PULLED NORTHWARD AHEAD OF AN UPPER
TROF THAT IS APPROACHING THE WEST COAST HAS NOW MOVED INTO SE CA AND
THE WESTERN 1/2 OF ARIZONA. THIS DRY AIR HAS PRETTY MUCH SHUT
CONVECTIVE ACTIVITY DOWN AND PUSHED SFC DEWPOINTS DOWN INTO THE
50S ACROSS THE WESTERN 3/4 OF OUR CWA THIS AFTERNOON.
AHEAD OF THIS DRY SURGE...THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED
THIS AFTERNOON ACROSS SOUTHER GILA COUNTY...WHERE DEWPOINTS ARE
STILL WELL UP IN THE 60S UNDER THE MAIN MONSOON MOISTURE PLUME AND
CONTINUED DIFFLUENCE ALOFT. THIS TS ACTIVITY IS NOW BEGINNING TO
SLOWLY DIMINISH AND SHIFT OFF TO THE NORTH THIS EVENING AS THE
MOISTURE PLUME CONTINUES TO SHIFT OFF SLOWLY TO THE EAST...WITH THE
LATEST HRRR HIGH-RES MODEL RUN INDICATING THAT ANY REMAINING
CONVECTIVE ACTIVITY TO END BY MIDNIGHT TONIGHT. TOMORROW STILL LOOKS
LIKE IT WILL BE THE 1ST IN A SERIES OF VERY QUIET DAYS AS DRY AIR
MAKES ITS WAY ACROSS ALL OF AZ. AS FAR AS THE SHORT-TERM GRIDDED AND
ZONE FORECASTS ARE CONCERNED...HAVE LOWERED POPS FOR THE REST OF
THIS EVENING AND TONIGHT INTO THE SINGLE-DIGIT RANGE ACROSS THE
LOWER DESERTS OF SOUTH-CENTRAL AZ AND HAVE MADE SOME MINOR EDITS TO
THE SHORT-TERM TEMPERATURE/DEWPOINT GRIDS TO BETTER REFLECT CURRENT
TRENDS.
&&
.DISCUSSION...
SO FAR THIS AFTERNOON WE HAVE LITTLE SHOWER OR THUNDERSTORM ACTIVITY
AS THE ATMOSPHERE JUST HAS NOT RECOVERED. SKIES HAVE REMAINED MOSTLY
CLEAR SO SUNSHINE HAS NOT BEEN AN ISSUE...BUT SURFACE TEMPERATURES
ARE STILL SOMEWHAT COOL FOR THIS TIME OF DAY AND GENERALLY 5-8
DEGREES COOLER THAN YESTERDAY. MESOSCALE ANALYSIS DOES SHOW AMPLE
MIXED LAYER CAPE ACROSS SOUTH-CENTRAL AND SOUTHEAST ARIZONA ALONG
WITH BROAD DIFFLUENCE OVER MUCH OF ARIZONA. STILL EXPECTING MORE
THUNDERSTORM DEVELOPMENT THROUGH THE REST OF THIS AFTERNOON...BUT
COVERAGE WILL LIKELY BE LIMITED TO MOSTLY HIGHER TERRAIN AREAS. HAVE
LOWERED POPS OVER THE LOWER DESERTS INTO THE SLIGHT CHANCE CATEGORY
DUE TO THE POOR CONVECTIVE START TO THE AFTERNOON...BUT WE SHOULD
STILL GET A FEW STORMS IN THE DESERTS BY THE END OF THE DAY. THERE IS
SOME POTENTIAL FOR SOME STRONG DOWNDRAFT WINDS WITH ANY STRONGER
STORMS...BUT WITH MORE MOIST AIR IN THE BOUNDARY LAYER...OUTFLOW
INTERACTIONS SHOULD BE LESS ACTIVE THAN YESTERDAY.
WATER VAPOR IMAGERY SHOWS DRY AIR QUICKLY MOVING NORTHWARD THROUGH
THE BAJA AREA INTO NORTHERN MEXICO AND MODELS SHOW THIS DRY AIR
WORKING ACROSS ARIZONA STARTING TONIGHT AND OVERTAKING ALL OF THE
STATE BY SUNDAY NIGHT. LINGERING LOWER LEVEL MOISTURE WILL ALLOW FOR
SOME HIGHER TERRAIN SHOWERS AND THUNDERSTORMS...BUT LITTLE TO NO
CHANCE OF ANY ACTIVITY OVER THE LOWER DESERTS. THIS DRY AIR WILL
BASICALLY END OUR STORM CHANCES FOR A FEW DAYS EARLY THIS
WEEK...WHILE TEMPERATURES START TO WARM UP. HIGHS ACROSS OUR
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA DESERTS WILL LIKELY BREAK
110 DEGREES SUNDAY THROUGH WEDNESDAY. SOUTH-CENTRAL ARIZONA DESERT
TEMPERATURES WILL PEAK ON MONDAY OR TUESDAY...BUT FALL SHORT OF
HITTING 110 DEGREES.
THE SUBTROPICAL HIGH POSITIONED OVER THE DESERT SOUTHWEST FOR MONDAY
AND TUESDAY IS FORECAST TO SHIFT EASTWARD INTO NEW MEXICO SOMETIME
WEDNESDAY AND THURSDAY AND REDIRECTING OUR FLOW OUT OF THE SOUTHEAST.
THIS WILL BRING A RETURN TO AT LEAST SOME LIMITED MONSOONAL MOISTURE
AND CHANCES FOR SHOWERS AND THUNDERSTORMS OVER MAINLY THE EASTERN
HALF OF ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
THROUGH 18Z SUN...SCT CLDS AOA 10 THSD FT AGL. LIGHT MOSTLY
SOUTHWEST WIND UNDER 8 KTS. HWVR...TSTMS OVR MTNS 50 MILES EAST OF
PHX THROUGH 06Z SUN.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
THROUGH 18Z SUN...SCT CLDS AOA 12 THSD AGL. LIGHT WIND UNDER 8 KNOTS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...DRIER AND STABLE WESTERLY FLOW ALOFT WILL
PRODUCE PARTLY CLOUDY SKIES TUESDAY AND WEDNESDAY...WITH LOWER
MINIMUM RELATIVE HUMIDITY GENERALLY IN THE 10 TO 15 PERCENT RANGE.
MOISTURE WILL GRADUALLY INCREASE OVER SOUTHWEST AND SOUTH CENTRAL
ARIZONA THURSDAY THROUGH SATURDAY...INTO THE 15 TO 25 PERCENT
RANGE...WITH A SLIGHT CHANCE OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS 10
TO 15 MPH. FAIR RECOVERY AT NIGHT.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/KUHLMAN
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
225 PM MST FRI JUL 31 2015
.SYNOPSIS...A MORE ACTIVE THUNDERSTORM DAY ACROSS SOUTHEAST ARIZONA
TODAY. ALTHOUGH SOME DRIER AIR WILL MOVE ACROSS THE AREA THIS
WEEKEND INTO NEXT WEEK...THERE WILL BE ENOUGH MOISTURE AROUND FOR A
CHANCE OF SHOWERS AND THUNDERSTORMS...MAINLY ALONG THE INTERNATIONAL
BORDER AS WELL AS THE MOUNTAIN TOPS.
&&
.DISCUSSION...WATER VAPOR IMAGERY AND 31/12Z UPPER-AIR PLOTS SHOW
THE CENTER OF HIGH PRESSURE IN THE GENERAL VICINITY OF THE TEXAS
PANHANDLE...WITH A PACIFIC LOW PRESSURE SYSTEM WELL OFF THE SOUTHERN
CALIFORNIA AND NORTHERN BAJA COASTS.
WHAT A DIFFERENCE 12 HOURS CAN MAKE. YESTERDAYS 31/00Z KTWC SOUNDING
REVEALED A PW OF 1.10 INCHES AND THE 31/12Z KTWC SOUNDING CAME IN
WITH A PW OF 1.68 INCHES. THIS MORNINGS SOUNDING PARAMETERS SHOWED A
MU CAPE OF AROUND 2200 J/KG AND A LIFTED INDEX OF MINUS 6. THE MOST
RECENT RADAR MOSAIC SHOWS SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS CONTINUING TO PROGRESS WESTWARD WEST OF AJO AND ORGAN
PIPE. ELSEWHERE ACROSS SOUTHEAST ARIZONA...ISOLATED TO SCATTERED
THUNDERSTORMS HAVE BEEN DEVELOPING DURING THE PAST HOUR OR TWO...
WITH CELLS EXTENDING FROM EAST OF ELOY TO PICTURE ROCKS AND TOWARD
ARIVACA. WEAK SHOWERS HAVE ALSO DEVELOPED OVER PARTS OF THE TUCSON
METRO AS WELL. ADDITIONAL CELLS ARE OCCURRING OVER THE HIGHER
TERRAIN OF GRAHAM...GREENLEE AND SANTA CRUZ COUNTIES...WITH ACTIVITY
MOVING WEST OR WEST NORTHWEST AT 5 TO 10 MPH.
U OF A 12Z WRF/NAM & GFS...AS WELL AS HRRR ALL SUGGEST THAT STORMS
WILL CONTINUE TO BLOSSOM OVER CENTRAL AND WESTERN PORTIONS OF THE
FORECAST AREA THIS AFTERNOON AND PUSH TO THE WEST OR WEST NORTHWEST
EARLY THIS EVENING. ACTIVITY NOT AS WIDESPREAD BETWEEN TUCSON AND
THE NEW MEXICO BORDER...WITH THE EXCEPTION OF THE MOUNTAIN TOPS.
KEPT A MENTION OF BLOWING DUST OVER PARTS OF PIMA AND PINAL COUNTIES
LATE THIS AFTERNOON AND EARLY THIS EVENING AS STORMS EXPECTED TO
FIRE OFF AND MOVE IN THAT GENERAL DIRECTION. THIS ALSO MESHES WELL
WITH THE FORECAST FROM THE PHOENIX OFFICE.
MODELS INDICATE THAT A WEAK DISTURBANCE COMING UP FROM THE SOUTH
WILL MOVE ACROSS SOUTH CENTRAL ARIZONA THIS EVENING AND THEN OVER
SOUTHWEST ARIZONA EARLY SATURDAY AND WESTERN ARIZONA MIDDAY
SATURDAY. AS THIS OCCURS...THIS SYSTEM WILL HELP TO ENHANCE ACTIVITY
THIS AFTERNOON AND EVENING...BUT BY SATURDAY WE SHOULD SEE LESS
THUNDERSTORM ACTIVITY AS THIS SYSTEM WILL BE OVER SRN NEVADA LATE IN
THE AFTERNOON AND MOISTURE IS EXPECTED TO DECREASE A BIT LATE IN THE
AFTERNOON OR INTO THE EVENING.
BY SUNDAY AND CONTINUING THROUGH AROUND WEDNESDAY THE HIGH IS
EXPECTED TO RECONSOLIDATE IN A WEST TO EAST ORIENTATION ACROSS
NORTHERN MEXICO AND THEN MOVE NORTH OVER THE DESERT SOUTHWEST BY
TUESDAY. AS A RESULT...DRIER SOUTHWEST TO WEST FLOW WILL REDUCE RAIN
CHANCES A BIT AND KEEP THE BEST THREAT FOR SHOWERS AND
THUNDERSTORMS...MAINLY BETWEEN NOGALES AND DOUGLAS AS WELL AS THE
WHITE MOUNTAINS. THIS WILL ALSO RESULT IN WARMER DAYTIME TEMPS
MONDAY THROUGH WEDNESDAY.
FOR LATE WEEK THE HIGH WILL SHIFT TOWARD THE EAST AND RESULT IN A
RETURN FLOW FROM THE SOUTH TO SOUTHEAST AND PULL IN MORE MOISTURE
AND INCREASING THUNDERSTORM CHANCES...BUT STILL JUST ISOLATED TO
SCATTERED IN NATURE.
FOR TUCSON...HIGHS WILL BE NEAR NORMAL SATURDAY...THEN 4 TO 7 DEGS
ABOVE NORMAL EACH DAY THROUGH FRIDAY. HOWEVER...THE WARMEST DAY WILL
LIKELY OCCUR TUESDAY. LOWS WILL RANGE FROM 2 TO 4 DEGS ABOVE NORMAL
EACH MORNING. HOWEVER...THE COOLEST MORNINGS WILL LIKELY OCCUR
MONDAY AND TUESDAY.
&&
.AVIATION...VALID THRU 02/00Z.
SCT TO BKN CLOUDS 7-10K FT AGL WITH SCT-NMRS SHRA/TSRA GENERALLY
BEFORE 01/04Z...AND MAINLY WEST OF A LINE FROM KOLS TO KSAD AND IN
THE WHITE MOUNTAINS. BRIEF MVFR CONDITIONS WITH ERRATIC WIND GUSTS
TO 45 KTS POSSIBLE IN AND AROUND THE STRONGER TSRA. AREAS OF BLDU
PSBL W AND NW OF KTUS AFT 31/22Z. OUTSIDE OF STORM INFLUENCES SFC
WINDS WILL GENERALLY BE LESS THAN 12 KTS WITH A FEW HIGHER GUSTS IN
THE AFTERNOON/EARLY EVENING HOURS. SHRA/TSRA WILL OCCUR AGAIN
SATURDAY AFTERNOON...ALTHOUGH WITH LESS COVERAGE THAN TODAY.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS
TODAY WITH STRONG OUTFLOW WINDS LIKELY...ESPECIALLY FROM TUCSON
WEST. SATURDAY WILL SEE SLIGHTLY LESS CONVECTION. INCREASING SW
WINDS ALOFT ON SUNDAY WILL BRING DRIER AIR INTO THE REGION FOR
ISOLATED TO SCATTERED THUNDERSTORM COVERAGE TO BEGIN NEXT
WEEK...WITH A FOCUS MAINLY SOUTH AND EAST OF TUCSON. OUTSIDE OF
THUNDERSTORM WIND GUSTS...20-FT WINDS WILL GENERALLY BE TERRAIN
DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME AFTERNOON AND EARLY
EVENING BREEZINESS IS LIKELY DUE TO DAYTIME HEATING...ESPECIALLY
THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
PUBLIC...MOLLERE
AVIATION/FIRE WEATHER...FRENCH
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1234 PM MST FRI JUL 31 2015
.UPDATE...UPDATED AVIATION DISCUSSION...
&&
.SYNOPSIS...
ISOLATED TO SCATTERED STORM ACTIVITY IS ANTICIPATED OVER ARIZONA AND
SOUTHEAST CALIFORNIA AGAIN TODAY. A NOTABLE DOWNTREND IN MOISTURE
FROM WEST TO EAST IS EXPECTED OVER THE WEEKEND. THIS WILL KEEP STORM
CHANCES LIMITED TO SOUTH- CENTRAL ARIZONA WELL INTO NEXT WEEK.
TEMPERATURES WILL NOT CHANGE MUCH DAY TO DAY REMAINING AT OR ABOVE
SEASONABLE AVERAGE.
&&
.DISCUSSION...
ISOLATED STORM ACTIVITY ALREADY GOING THIS MORNING ALONG OUR
BOUNDARY WITH TWC CWA AND ADDITIONAL SHOWERS FURTHER SOUTH. THESE
APPEAR TO BE INFLUENCED BY REMNANTS OF A COUPLE OF OVERNIGHT MCS/S.
THERE ALSO LOOKS TO BE A BACKDOOR FRONT THAT HAS PUSHED THROUGH MUCH
OF NEW MEXICO. SO THERE COULD BE A COUPLE OF MCV/S AFFECTING THE AREA
TODAY...AND SOME OF THE HIGH RES MODELS DEPICT THAT. UNFORTUNATELY
NONE OF THE HIGH RES MODELS HAVE CAPTURED THIS MORNING/S ACTIVITY
VERY WELL...EVEN THE ONES THAT DID HANDLE THE EARLIER MCS/S FAIRLY
WELL. THE HRRR RUNS THIS MORNING HAVE BEEN INDICATING DEVELOPMENT
OVER SOUTH-CENTRAL ARIZONA...INCLUDING THE LOWER DESERTS...EARLIER
IN THE DAY THAN IS TYPICAL. OVERALL...NOT A LOT OF GOOD AGREEMENT
AMONGST THE MODELS ON THE SPATIAL COVERAGE OF STORMS. ONE SIMILARITY
IS THAT THERE SHOULD BE MORE STORMS OVER SOUTH-CENTRAL ARIZONA TODAY
THAN YESTERDAY. WILL MAKE SOME ADDITIONAL UPWARD ADJUSTMENTS TO POPS.
MORE LATER.
&&
.PREVIOUS DISCUSSION 334 AM MST/PDT...
LOOKING AT 00Z SOUNDINGS FROM BOTH TUCSON AND PHOENIX...SOMEWHAT
DRIER COMPARED TO 12Z ON THURSDAY...HOWEVER STILL FAIRLY AVERAGE FOR
THIS TIME OF YEAR FOR PWAT VALUES. AFTER AN ACTIVE EVENING ACROSS
SOUTHEAST ARIZONA AND SOUTHEAST CALIFORNIA...PER LATEST IR SATELLITE
IMAGERY A NICE MCS HAS MADE AN APPEARANCE OVER SONORA AND IS TRACKING
WESTWARD BUT STILL DELIVERING A VAST AMOUNT OF CLOUD COVER AND
ISOLATED LIGHTNING THIS SIDE OF THE BORDER. THE STRUGGLE TODAY WILL
BE CLOUD COVER AND IF IT WILL HINDER CONVECTION OPPORTUNITIES INTO
THE CENTRAL DESERTS.
STILL UNDER THE INFLUENCE OF SOUTH-SOUTHEASTERLY FLOW ON THE BACKSIDE
OF THE HIGH...THE SHORTWAVE FEATURE THAT IS PROVIDING THE LIFT AND
DYNAMICS CONTINUES TO MOVE NORTHWARD INTO THE FOUR CORNERS REGION.
PRECIPITABLE WATER READINGS ARE FORECAST TO REACH 1.65-1.7 INCH
THROUGH SATURDAY EVENING...WHICH AGAIN IS ABOUT PAR FOR THE COURSE
THIS TIME OF YEAR. TWO OUT OF THREE KEY INGREDIENTS FOR STORM
INITIATION ARE PRESENT AND THE THIRD REALLY HINGES ON DAYTIME
HEATING. AS WE SAW A FEW DAYS AGO THE CLOUDS PLAY A LARGE PART IN
WHETHER STORMS WILL INITIATE OR NOT. BOUNDARY LAYER AND OUTFLOW
INTERACTION ALWAYS AIDE WITH DEVELOPMENT. LOCAL MESOSCALE CONVECTIVE
MODELS ALLUDE TO CLOUDS CLEARING BY MID MORNING FOR CENTRAL ARIZONA
AS WELL AS ELEVATED INSTABILITY BY MID-DAY /CLOSE TO 800 J/KG OF
CAPE/ WHICH WOULD LATER BE REALIZED WITH DAYTIME HEATING. ALL THIS
SAID...TODAY COULD PLAY OUT EITHER WITH STABLE CONDITIONS PERSISTING
DUE TO NO CLEARING OR MID TO LATE AFTERNOON CONVECTION WILL INITIATE
SOUTHEAST OF PHOENIX AND PROPAGATE NORTHWARD. I AM TENDING TO LEAN ON
THE CLEARING OUT OPTION.
FORECAST SOUNDINGS INDICATE A DRY BOUNDARY LAYER /7-8 G/KG MIXING
RATIO/ WITH SUFFICIENT HEATING CREATING AN INVERTED-V TYPE SOUNDING
WITH WARMER MAX TEMPS THIS AFTERNOON. INSTABILITY IN PLACE AND
CONVECTION DEVELOPING SOUTHEAST OF PHOENIX WITH A SOUTHEASTERLY
FLOW...SIGNS POINT TO BLOWING DUST. ALL HIGH-RES MODELS TEND TO AGREE
ON A RATHER ACTIVE EVENING ACROSS THE LOWER DESERTS. WHILE NOT A
SLAM-DUNK FLOOD SCENARIO...CAN`T RULE OUT LOCALIZED FLOODING...AS
WELL AS GUSTY WINDS WITH THE STRONGER STORMS.
AFTER TODAY DRIER AIR BEGINS TO FILTER IN WITH A SOUTHWESTERLY FLOW
STARTING TO TAKE SHAPE. SATURDAY HAS LESS THAN IDEAL CONDITIONS FOR
MONSOONAL ACTIVITY ACROSS THE LOWER AND CENTRAL DESERTS WITH MORE OF
A CONFLUENT FLOW. MOUNTAIN LOCATIONS OF EASTERN ARIZONA WILL STILL
SEE A SLIGHT OR BETTER CHANCE FOR AFTERNOON AND EVENING CONVECTION
FOR THE NEXT SEVERAL DAYS...GRADUALLY TRENDING DOWNWARD. SLIGHT
WARMING WILL ALSO TAKE PLACE WITH TEMPERATURES RANGING 102 TO 108
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
AN ACTIVE START TO THE AFTERNOON WITH QUITE A BIT OF STORM ACTIVITY
ALREADY FIRING OVER THE MOUNTAINS TO THE NORTH AND EAST OF PHOENIX.
EVENTUALLY EXPECTING SOME STORM OUTFLOWS TO ALLOW FOR MORE STORM
DEVELOPMENT OVER THE LOWER DESERTS BY LATE AFTERNOON. CONFIDENCE IN
TIMING FOR STORMS IN THE LOWER DESERTS IS STILL SOMEWHAT LOW...BUT
WE MAY SEE SOME OUTFLOWS INTO THE PHOENIX TERMINALS AS SOON AS 22-
00Z AND THEN A SHOT AT SOME THUNDERSTORMS DURING THE EVENING HOURS.
WIND FORECASTS THROUGH MIDNIGHT ARE RATHER TRICKY DUE TO THE STRONG
LIKELIHOOD OF STORM OUTFLOWS AFFECTING THE AREA. THERE IS POTENTIAL
FOR SOME STRONG WIND GUSTS WITH THESE OUTFLOWS AND VISIBILITY
RESTRICTIONS IN DUST OR RAIN.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
WEST WINDS TO HOLD MOSTLY FOR KIPL THROUGHOUT THE DAY WHILE
SOUTHERLY HEADINGS ARE IN STORE FOR KBLH. SLIGHT CHANCE FOR ISOLATED
THUNDERSTORM DEVELOPMENT INTO THE AFTN ALONG THE CO RIVER
VALLEY...SO AT LEAST VCSH MENTION IS BACK IN THE KBLH TAF FOR THE
AFTN/EVENING HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
MONSOONAL MOISTURE WILL SLOWLY BEGIN TO THIN ACROSS THE AREA...FIRST
ACROSS THE WESTERN FIRE DISTRICTS AND EVENTUALLY INTO THE ENTIRE
LOWER DESERT ELEVATIONS AND REGION BY EARLY NEXT WEEK. THIS WILL
RELEGATE STORM CHANCES BACK TOWARDS THE HIGHER TERRAIN AND FURTHER
TO THE EAST ACROSS AZ. MINIMUM RH VALUES WILL BEGIN TO SETTLE INTO
THE TEENS WHILE MAKING MOSTLY MODEST TO FAIR OVERNIGHT RECOVERIES.
THE SLIGHTLY DRIER AIRMASS AND BUILDING UPPER RIDGE HEIGHTS WILL
LEND THEMSELVES TOWARD WARMER SFC CONDITIONS...AT OR ABOVE SEASONAL
NORMALS. WINDS WILL FOLLOW FAMILIAR WARM SEASON PATTERNS. BY MIDWEEK
A SUBTLE RETURN OF GULF MOISTURE MAY BOOST AREA HUMIDITIES...BUT NOT
LINGER MUCH THROUGH THE END OF THE WEEK.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...DEWEY
AVIATION...KUHLMAN
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
941 AM MST FRI JUL 31 2015
.SYNOPSIS...
ISOLATED TO SCATTERED STORM ACTIVITY IS ANTICIPATED OVER ARIZONA AND
SOUTHEAST CALIFORNIA AGAIN TODAY. A NOTABLE DOWNTREND IN MOISTURE
FROM WEST TO EAST IS EXPECTED OVER THE WEEKEND. THIS WILL KEEP STORM
CHANCES LIMITED TO SOUTH- CENTRAL ARIZONA WELL INTO NEXT WEEK.
TEMPERATURES WILL NOT CHANGE MUCH DAY TO DAY REMAINING AT OR ABOVE
SEASONABLE AVERAGE.
&&
.DISCUSSION...
ISOLATED STORM ACTIVITY ALREADY GOING THIS MORNING ALONG OUR
BOUNDARY WITH TWC CWA AND ADDITIONAL SHOWERS FURTHER SOUTH. THESE
APPEAR TO BE INFLUENCED BY REMNANTS OF A COUPLE OF OVERNIGHT MCS/S.
THERE ALSO LOOKS TO BE A BACKDOOR FRONT THAT HAS PUSHED THROUGH MUCH
OF NEW MEXICO. SO THERE COULD BE A COUPLE OF MCV/S AFFECTING THE AREA
TODAY...AND SOME OF THE HIGH RES MODELS DEPICT THAT. UNFORTUNATELY
NONE OF THE HIGH RES MODELS HAVE CAPTURED THIS MORNING/S ACTIVITY
VERY WELL...EVEN THE ONES THAT DID HANDLE THE EARLIER MCS/S FAIRLY
WELL. THE HRRR RUNS THIS MORNING HAVE BEEN INDICATING DEVELOPMENT
OVER SOUTH-CENTRAL ARIZONA...INCLUDING THE LOWER DESERTS...EARLIER
IN THE DAY THAN IS TYPICAL. OVERALL...NOT A LOT OF GOOD AGREEMENT
AMONGST THE MODELS ON THE SPATIAL COVERAGE OF STORMS. ONE SIMILARITY
IS THAT THERE SHOULD BE MORE STORMS OVER SOUTH-CENTRAL ARIZONA TODAY
THAN YESTERDAY. WILL MAKE SOME ADDITIONAL UPWARD ADJUSTMENTS TO POPS.
MORE LATER.
&&
.PREVIOUS DISCUSSION 334 AM MST/PDT...
LOOKING AT 00Z SOUNDINGS FROM BOTH TUCSON AND PHOENIX...SOMEWHAT
DRIER COMPARED TO 12Z ON THURSDAY...HOWEVER STILL FAIRLY AVERAGE FOR
THIS TIME OF YEAR FOR PWAT VALUES. AFTER AN ACTIVE EVENING ACROSS
SOUTHEAST ARIZONA AND SOUTHEAST CALIFORNIA...PER LATEST IR SATELLITE
IMAGERY A NICE MCS HAS MADE AN APPEARANCE OVER SONORA AND IS TRACKING
WESTWARD BUT STILL DELIVERING A VAST AMOUNT OF CLOUD COVER AND
ISOLATED LIGHTNING THIS SIDE OF THE BORDER. THE STRUGGLE TODAY WILL
BE CLOUD COVER AND IF IT WILL HINDER CONVECTION OPPORTUNITIES INTO
THE CENTRAL DESERTS.
STILL UNDER THE INFLUENCE OF SOUTH-SOUTHEASTERLY FLOW ON THE BACKSIDE
OF THE HIGH...THE SHORTWAVE FEATURE THAT IS PROVIDING THE LIFT AND
DYNAMICS CONTINUES TO MOVE NORTHWARD INTO THE FOUR CORNERS REGION.
PRECIPITABLE WATER READINGS ARE FORECAST TO REACH 1.65-1.7 INCH
THROUGH SATURDAY EVENING...WHICH AGAIN IS ABOUT PAR FOR THE COURSE
THIS TIME OF YEAR. TWO OUT OF THREE KEY INGREDIENTS FOR STORM
INITIATION ARE PRESENT AND THE THIRD REALLY HINGES ON DAYTIME
HEATING. AS WE SAW A FEW DAYS AGO THE CLOUDS PLAY A LARGE PART IN
WHETHER STORMS WILL INITIATE OR NOT. BOUNDARY LAYER AND OUTFLOW
INTERACTION ALWAYS AIDE WITH DEVELOPMENT. LOCAL MESOSCALE CONVECTIVE
MODELS ALLUDE TO CLOUDS CLEARING BY MID MORNING FOR CENTRAL ARIZONA
AS WELL AS ELEVATED INSTABILITY BY MID-DAY /CLOSE TO 800 J/KG OF
CAPE/ WHICH WOULD LATER BE REALIZED WITH DAYTIME HEATING. ALL THIS
SAID...TODAY COULD PLAY OUT EITHER WITH STABLE CONDITIONS PERSISTING
DUE TO NO CLEARING OR MID TO LATE AFTERNOON CONVECTION WILL INITIATE
SOUTHEAST OF PHOENIX AND PROPAGATE NORTHWARD. I AM TENDING TO LEAN ON
THE CLEARING OUT OPTION.
FORECAST SOUNDINGS INDICATE A DRY BOUNDARY LAYER /7-8 G/KG MIXING
RATIO/ WITH SUFFICIENT HEATING CREATING AN INVERTED-V TYPE SOUNDING
WITH WARMER MAX TEMPS THIS AFTERNOON. INSTABILITY IN PLACE AND
CONVECTION DEVELOPING SOUTHEAST OF PHOENIX WITH A SOUTHEASTERLY
FLOW...SIGNS POINT TO BLOWING DUST. ALL HIGH-RES MODELS TEND TO AGREE
ON A RATHER ACTIVE EVENING ACROSS THE LOWER DESERTS. WHILE NOT A
SLAM-DUNK FLOOD SCENARIO...CAN`T RULE OUT LOCALIZED FLOODING...AS
WELL AS GUSTY WINDS WITH THE STRONGER STORMS.
AFTER TODAY DRIER AIR BEGINS TO FILTER IN WITH A SOUTHWESTERLY FLOW
STARTING TO TAKE SHAPE. SATURDAY HAS LESS THAN IDEAL CONDITIONS FOR
MONSOONAL ACTIVITY ACROSS THE LOWER AND CENTRAL DESERTS WITH MORE OF
A CONFLUENT FLOW. MOUNTAIN LOCATIONS OF EASTERN ARIZONA WILL STILL
SEE A SLIGHT OR BETTER CHANCE FOR AFTERNOON AND EVENING CONVECTION
FOR THE NEXT SEVERAL DAYS...GRADUALLY TRENDING DOWNWARD. SLIGHT
WARMING WILL ALSO TAKE PLACE WITH TEMPERATURES RANGING 102 TO 108
EACH DAY.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
BKN-OVC MID AND HIGH LEVEL CIGS WILL CONTINUE TO DRIFT ACROSS THE
AREA THIS AM FROM DECAYING STORM COMPLEXES SOUTH OF THE BORDER AND
ACROSS SE AZ. HOW FAST AND TO WHAT EXTENT THESE CLEAR TODAY WILL
EITHER HELP OR HURT THE PHX METRO IN TERMS OF STORM CHANCES
IMPACTING THE TERMINALS LATER INTO THE EVENING. GNLY LIGHT AM SFC
WINDS NOTED AT SITES AROUND THE METRO WITH SUBTLE WEST FLOW VIA TPHX
AND KIWA VELOCITIES...SO ELECTED TO GO WITH VRB IN FOR PHX. SPEEDS
SHOULD BE LIGHT AND MANAGEABLE UNTIL MORE PROMINENT WESTERLY FLOW
SETTLES INTO THE AREA AFTER MIDDAY.
IF SKIES CLEAR AND WE ARE ABLE TO DECENTLY WARM THE DESERTS...STORMS
ARE FCST TO BEGIN FIRING OVER THE HIGHER TERRAIN AND FOOTHILLS EAST
AND SOUTH OF PHOENIX. STORM INITIATION AND/OR SURVIVAL INTO THE PHX
METRO WILL LIKELY DEPEND ON STORM OUTFLOWS AND THEIR INTERACTION.
FOLLOWING HOW CONDITIONS HAVE MATERIALIZED SO FAR THIS
SUMMER...THESE OUTFLOW PASSAGES TEND BE POST 00Z...SO DID INCLUDE
VCTS MENTION 01/02Z FOR KSDL AND KIWA AND 01/04Z FOR KPHX.
CONFIDENCE IS MODERATE ON STORM DEVELOPMENT THIS EVENING...HOPING
THAT DAYTIME CLOUD COVER CLEARS ENOUGH TO NOT DAMPEN/SHUT DOWN STORM
CHANCES LATER INTO THE EVENING.
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
SCT-BKN MID LEVEL CLOUDS WILL CONTINUE TO STREAM OVER THE TERMINALS
FROM THE SOUTH THROUGH THE AM...OTHERWISE SKIES WILL MAINTAIN FEW-
SCT CLOUD COVERAGE. WEST WINDS TO HOLD MOSTLY FOR KIPL THROUGHOUT
THE DAY WHILE SOUTHERLY HEADINGS ARE IN STORE FOR KBLH. SLIGHT
CHANCE FOR ISOLATED THUNDERSTORM DEVELOPMENT INTO THE AFTN ALONG THE
CO RIVER VALLEY...SO AT LEAST VCSH MENTION IS BACK IN THE KBLH TAF
FOR THE AFTN/EVENING HOURS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
SUNDAY THROUGH THURSDAY...
MONSOONAL MOISTURE WILL SLOWLY BEGIN TO THIN ACROSS THE AREA...FIRST
ACROSS THE WESTERN FIRE DISTRICTS AND EVENTUALLY INTO THE ENTIRE
LOWER DESERT ELEVATIONS AND REGION BY EARLY NEXT WEEK. THIS WILL
RELEGATE STORM CHANCES BACK TOWARDS THE HIGHER TERRAIN AND FURTHER
TO THE EAST ACROSS AZ. MINIMUM RH VALUES WILL BEGIN TO SETTLE INTO
THE TEENS WHILE MAKING MOSTLY MODEST TO FAIR OVERNIGHT RECOVERIES.
THE SLIGHTLY DRIER AIRMASS AND BUILDING UPPER RIDGE HEIGHTS WILL
LEND THEMSELVES TOWARD WARMER SFC CONDITIONS...AT OR ABOVE SEASONAL
NORMALS. WINDS WILL FOLLOW FAMILIAR WARM SEASON PATTERNS. BY MIDWEEK
A SUBTLE RETURN OF GULF MOISTURE MAY BOOST AREA HUMIDITIES...BUT NOT
LINGER MUCH THROUGH THE END OF THE WEEK.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...AJ
PREVIOUS DISCUSSION...DEWEY
AVIATION...NOLTE
FIRE WEATHER...NOLTE
AREA FORECAST DISCUSSION
NWS RENO NV
1007 AM PDT FRI JUL 31 2015
.UPDATE...
MADE A QUICK UPDATE THIS MORNING TO DECREASE COVERAGE OF EXPECTED
THUNDERSTORMS TODAY IN MONO COUNTY TO ISOLATED, INSTEAD OF
SCATTERED. ABUNDANT CLOUD COVER WILL KEEP INSTABILITY MARGINALIZED
THROUGH THE DAY, RESULTING IN LESS THUNDERSTORM POTENTIAL. STILL,
ANY STORMS THAT DO HAPPEN TO FORM WILL HAVE TO OVERCOME A VERY DRY
BOUNDARY LAYER, SO LITTLE RAINFALL IS EXPECTED OVERALL WITH VIRGA
SHOWERS COMMON TODAY. HOON
&&
.PREVIOUS DISCUSSION... /ISSUED 304 AM PDT FRI JUL 31 2015/
SYNOPSIS...
MOISTURE WILL SPREAD NORTH ACROSS THE REGION TODAY AND BRING A
CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY NEAR THE SIERRA AND IN
WESTERN NEVADA SOUTH OF HIGHWAY 50, WITH GUSTY OUTFLOW WINDS AND
LIGHTNING INDUCED FIRE STARTS POSSIBLE. THE BEST OVERALL SHOWER
AND THUNDERSTORM POTENTIAL IS EXPECTED FOR THIS WEEKEND, WITH
LOCALLY HEAVY RAINFALL AND FLOODING BECOMING THE MAIN THREATS.
SHORT TERM...
MID AND HIGH LEVEL MOISTURE CONTINUES TO SPREAD NORTH ACROSS
CALIFORNIA AND NEVADA THROUGH THE EARLY MORNING. ANOTHER WEAK
IMPULSE FARTHER SOUTH ACROSS INYO AND NYE COUNTIES IS BEING
PICKED UP BY THE LATEST NAM AND HRRR GUIDANCE, WHICH SPREAD SOME
SHOWERS ACROSS MONO, ALPINE AND SOUTHERN MINERAL COUNTIES DURING
THE EARLY AND MID MORNING.
FOR THE REMAINDER OF TODAY, FAVORED AREAS FOR AFTERNOON CONVECTION
APPEAR TO BE LIMITED TO AREAS NEAR THE SIERRA FROM MONO COUNTY
NORTHWARD TO WESTERN LASSEN COUNTY, AND IN WESTERN NV SOUTH OF
HIGHWAY 50. ELSEWHERE, THICKER CLOUD COVER SPREADING ACROSS
WESTERN NV AND NORTHEAST CA DURING THE DAY COMBINED WITH DRY EAST
FLOW NEAR THE SURFACE MAY PRODUCE CONDITIONS TOO STABLE FOR
FORMING OR SUSTAINING CONVECTION THAT MOVES NORTH OF HIGHWAY 50.
HOWEVER, OUTFLOWS FROM CELLS THAT DEVELOP NEAR THE SIERRA COULD
PUSH ACROSS WESTERN NV AND BRING A SHORT PERIOD OF STRONGER WIND
GUSTS BY LATE AFTERNOON OR EARLY EVENING. MOST ACTIVITY WILL
DIMINISH TONIGHT, ALTHOUGH A FEW BRIEF CELLS CAN`T BE RULED OUT
MAINLY SOUTH OF HIGHWAY 50 AS MOISTURE CONTINUES TO INCREASE
OVERNIGHT.
THE MAIN CONVECTIVE POTENTIAL IS EXPECTED THIS WEEKEND AS MOISTURE
CONTINUES TO SURGE NORTHWARD. WHILE CLOUD COVER COULD STILL DISRUPT
CONVECTIVE DEVELOPMENT, THERE APPEARS TO BE A LARGER WINDOW OF
HEATING ON SATURDAY, ALONG WITH RISING DEW POINTS CONTRIBUTING TO
MORE INSTABILITY. A STRONGER UPPER LEVEL DISTURBANCE IS ALSO
PROJECTED TO MOVE NORTH ACROSS THE SIERRA WITH ANOTHER DISTURBANCE
TRACKING NORTHWARD ACROSS CENTRAL NV. THESE FEATURES WOULD PROVIDE
ADDITIONAL FORCING AND INCREASE SHOWER AND THUNDERSTORM COVERAGE
WHICH MAY HOLD TOGETHER THROUGH SATURDAY NIGHT. THE CURRENT
SHORTWAVE TRACKS ARE FAVORING SOME OVERNIGHT PRECIP ACROSS THE
TAHOE BASIN AND THE RENO-CARSON CITY VICINITY, ALTHOUGH THIS COULD
VARY SINCE THE TRACK OF THESE DISTURBANCES ARE LIKELY TO CHANGE
WITH UPCOMING MODEL RUNS.
FOR SUNDAY, ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS PROBABLE
WITH VERY MOIST AND UNSTABLE CONDITIONS REMAINING. IF FULL
INSTABILITY IS REALIZED, THEN SOME STRONG STORMS WITH HEAVY RAIN
WOULD DEVELOP. HOWEVER, THERE COULD BE TOO MUCH LEFTOVER CLOUD
COVER FROM SATURDAY NIGHT`S ACTIVITY WHICH LIMITS HEATING AND
CELL STRENGTH ON SUNDAY. THIS LIMITING FACTOR IS MORE PRONOUNCED
ON THE GFS WHICH IS HOLDING MAX TEMPS DOWN TO THE MID-UPPER 80S
ACROSS WESTERN NV. WE DIDN`T MAKE MUCH CHANGE TO THE CURRENT
SUNDAY FORECAST WITH CHANCE POPS KEPT OVER MOST AREAS, SINCE
THERE IS A LOT OF UNCERTAINTY WITH THE DETAILS OF WHERE CONVECTION
EVENTUALLY OCCURS. MJD
LONG TERM...MONDAY THROUGH THURSDAY...
THE OVERALL IDEA FOR NEXT WEEK`S FORECAST HAS NOT CHANGED, BUT DID
MAKE SOME CHANGES TO THE DETAILS. DRIER SOUTHWEST FLOW IS EXPECTED
TO BEGIN MONDAY AND CONTINUE THROUGH THE WEEK. SOME MOISTURE WILL BE
LEFT OVER MONDAY FOR SOME SHOWERS AND THUNDERSTORMS. HOWEVER, PUSHED
THE BEST CHANCES TO MONO/MINERAL WHERE THE SOUTHWEST FLOW WILL BE
WEAKEST. WHILE IT WON`T DRY OUT QUICKLY, THE ZEPHYR ACTS TO LIMIT
THUNDERSTORM DEVELOPMENT BEHIND ITS LEADING EDGE. I WOULD NOT BE
SURPRISED IF THE TAHOE BASIN IS COMPLETELY DRY AS EARLY AS MONDAY
AND POSSIBLY THE SIERRA FRONT OUTSIDE THE PINE NUTS.
TUESDAY THROUGH THURSDAY, DRY SOUTHWEST FLOW WILL CONTINUE. ONE
THING TO NOTE IS THAT THERE IS ANOTHER WAVE EMBEDDED IN THE FLOW FOR
TUESDAY THAT COULD BACK THE FLOW TO THE SOUTH OVER MONO/MINERAL AND
KEEP THUNDERSTORMS POSSIBLE THERE. THE EC IS SHOWING THIS IDEA,
WHILE THE GFS IS DRY. WILL KEEP TUESDAY DRY FOR NOW UNTIL THERE IS
MORE CONSISTENCY.
AS FOR THE WINDS, THEY LOOK TO BE FAIRLY TYPICAL FOR MIDSUMMER WITH
AN AFTERNOON/EVENING ZEPHYR EACH DAY AND GUSTS 25-30 MPH.
TEMPERATURES WILL ALSO COOL BACK CLOSER TO AVERAGE IF NOT A LITTLE
BELOW. WALLMANN
AVIATION...
VFR CONDITIONS AS MONSOONAL MOISTURE STREAMS NORTH TODAY WITH
BROKEN MID AND HIGH CLOUDS. A FEW LIGHT SHOWERS POSSIBLE THIS
MORNING WITH ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
ALONG AND JUST EAST OF THE SIERRA. COVERAGE MAY BE MORE OVER MONO
COUNTY INCLUDING KMMH, BUT THIS WILL BE DEPENDENT ON CLOUD COVER
THIS MORNING. MAIN THREAT WILL BE GUSTY OUTFLOW WINDS 40+ KTS AND
ASSOCIATED WIND SHEAR.
MORE CLOUDS TONIGHT BEFORE A POTENTIAL REPEAT ON SATURDAY. MOISTURE
INCREASES, BUT THE STORM COVERAGE WILL BE DEPENDENT ON CLOUD COVER.
WALLMANN
FIRE WEATHER...
MAIN CONCERN WILL BE LIGHTNING TODAY WITH STORMS AS MOISTURE
CONTINUES TO INCREASE. CLOUD COVER IS FAIRLY EXTENSIVE THIS
MORNING SO COVERAGE IS LIKELY TO REMAIN ISOLATED. STORMS WILL
START DRY AND BECOME WET/DRY HYBRIDS AS THE DAY PROGRESSES. AS WE
MOVE INTO SATURDAY, MOISTURE WILL CONTINUE TO INCREASE AND EXPECT
HYBRID STORMS THAT DAY. GIVEN THE DRYNESS AND HEAT PRECEDING, IT
COULD BE A POTENTIALLY ACTIVE DAY. HOWEVER, CLOUD COVER LOOKS LIKE
IT MIGHT BE EXTENSIVE THAT WOULD REDUCE THE INSTABILITY AND
COVERAGE OF STORMS. GIVEN THE UNCERTAINTY, WILL NOT ISSUE A FIRE
WEATHER WATCH FOR DRY LIGHTNING.
AS WE MOVE INTO SUNDAY, MORE MOISTURE WILL BE PRESENT AND STORMS
WILL BE SLOW MOVING. AT THAT POINT, HEAVY RAIN WILL BE THE BIGGER
CONCERN ALTHOUGH A FEW STARTS OUTSIDE THE CORES WILL REMAIN
POSSIBLE. HUMIDITY WILL ALSO BE HIGHER TOO WITH MINIMUMS LIKELY TO
REMAIN ABOVE 20% IN WESTERN NV AND 30% IN THE SIERRA. DRY SOUTHWEST
FLOW IS EXPECTED NEXT WEEK WITH A FEW STORMS POSSIBLE MONDAY. WINDS
NEXT WEEK LOOK TO BE TYPICAL ZEPHYRS WITH GUSTS 25-30 MPH. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS RENO NV
304 AM PDT FRI JUL 31 2015
.SYNOPSIS...
MOISTURE WILL SPREAD NORTH ACROSS THE REGION TODAY AND BRING A
CHANCE FOR SHOWERS AND THUNDERSTORMS MAINLY NEAR THE SIERRA AND IN
WESTERN NEVADA SOUTH OF HIGHWAY 50, WITH GUSTY OUTFLOW WINDS AND
LIGHTNING INDUCED FIRE STARTS POSSIBLE. THE BEST OVERALL SHOWER
AND THUNDERSTORM POTENTIAL IS EXPECTED FOR THIS WEEKEND, WITH
LOCALLY HEAVY RAINFALL AND FLOODING BECOMING THE MAIN THREATS.
&&
.SHORT TERM...
MID AND HIGH LEVEL MOISTURE CONTINUES TO SPREAD NORTH ACROSS
CALIFORNIA AND NEVADA THROUGH THE EARLY MORNING. ANOTHER WEAK
IMPULSE FARTHER SOUTH ACROSS INYO AND NYE COUNTIES IS BEING
PICKED UP BY THE LATEST NAM AND HRRR GUIDANCE, WHICH SPREAD SOME
SHOWERS ACROSS MONO, ALPINE AND SOUTHERN MINERAL COUNTIES DURING
THE EARLY AND MID MORNING.
FOR THE REMAINDER OF TODAY, FAVORED AREAS FOR AFTERNOON CONVECTION
APPEAR TO BE LIMITED TO AREAS NEAR THE SIERRA FROM MONO COUNTY
NORTHWARD TO WESTERN LASSEN COUNTY, AND IN WESTERN NV SOUTH OF
HIGHWAY 50. ELSEWHERE, THICKER CLOUD COVER SPREADING ACROSS
WESTERN NV AND NORTHEAST CA DURING THE DAY COMBINED WITH DRY EAST
FLOW NEAR THE SURFACE MAY PRODUCE CONDITIONS TOO STABLE FOR
FORMING OR SUSTAINING CONVECTION THAT MOVES NORTH OF HIGHWAY 50.
HOWEVER, OUTFLOWS FROM CELLS THAT DEVELOP NEAR THE SIERRA COULD
PUSH ACROSS WESTERN NV AND BRING A SHORT PERIOD OF STRONGER WIND
GUSTS BY LATE AFTERNOON OR EARLY EVENING. MOST ACTIVITY WILL
DIMINISH TONIGHT, ALTHOUGH A FEW BRIEF CELLS CAN`T BE RULED OUT
MAINLY SOUTH OF HIGHWAY 50 AS MOISTURE CONTINUES TO INCREASE
OVERNIGHT.
THE MAIN CONVECTIVE POTENTIAL IS EXPECTED THIS WEEKEND AS MOISTURE
CONTINUES TO SURGE NORTHWARD. WHILE CLOUD COVER COULD STILL DISRUPT
CONVECTIVE DEVELOPMENT, THERE APPEARS TO BE A LARGER WINDOW OF
HEATING ON SATURDAY, ALONG WITH RISING DEW POINTS CONTRIBUTING TO
MORE INSTABILITY. A STRONGER UPPER LEVEL DISTURBANCE IS ALSO
PROJECTED TO MOVE NORTH ACROSS THE SIERRA WITH ANOTHER DISTURBANCE
TRACKING NORTHWARD ACROSS CENTRAL NV. THESE FEATURES WOULD PROVIDE
ADDITIONAL FORCING AND INCREASE SHOWER AND THUNDERSTORM COVERAGE
WHICH MAY HOLD TOGETHER THROUGH SATURDAY NIGHT. THE CURRENT
SHORTWAVE TRACKS ARE FAVORING SOME OVERNIGHT PRECIP ACROSS THE
TAHOE BASIN AND THE RENO-CARSON CITY VICINITY, ALTHOUGH THIS COULD
VARY SINCE THE TRACK OF THESE DISTURBANCES ARE LIKELY TO CHANGE
WITH UPCOMING MODEL RUNS.
FOR SUNDAY, ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS IS PROBABLE
WITH VERY MOIST AND UNSTABLE CONDITIONS REMAINING. IF FULL
INSTABILITY IS REALIZED, THEN SOME STRONG STORMS WITH HEAVY RAIN
WOULD DEVELOP. HOWEVER, THERE COULD BE TOO MUCH LEFTOVER CLOUD
COVER FROM SATURDAY NIGHT`S ACTIVITY WHICH LIMITS HEATING AND
CELL STRENGTH ON SUNDAY. THIS LIMITING FACTOR IS MORE PRONOUNCED
ON THE GFS WHICH IS HOLDING MAX TEMPS DOWN TO THE MID-UPPER 80S
ACROSS WESTERN NV. WE DIDN`T MAKE MUCH CHANGE TO THE CURRENT
SUNDAY FORECAST WITH CHANCE POPS KEPT OVER MOST AREAS, SINCE
THERE IS A LOT OF UNCERTAINTY WITH THE DETAILS OF WHERE CONVECTION
EVENTUALLY OCCURS. MJD
.LONG TERM...MONDAY THROUGH THURSDAY...
THE OVERALL IDEA FOR NEXT WEEK`S FORECAST HAS NOT CHANGED, BUT DID
MAKE SOME CHANGES TO THE DETAILS. DRIER SOUTHWEST FLOW IS EXPECTED
TO BEGIN MONDAY AND CONTINUE THROUGH THE WEEK. SOME MOISTURE WILL BE
LEFT OVER MONDAY FOR SOME SHOWERS AND THUNDERSTORMS. HOWEVER, PUSHED
THE BEST CHANCES TO MONO/MINERAL WHERE THE SOUTHWEST FLOW WILL BE
WEAKEST. WHILE IT WON`T DRY OUT QUICKLY, THE ZEPHYR ACTS TO LIMIT
THUNDERSTORM DEVELOPMENT BEHIND ITS LEADING EDGE. I WOULD NOT BE
SURPRISED IF THE TAHOE BASIN IS COMPLETELY DRY AS EARLY AS MONDAY
AND POSSIBLY THE SIERRA FRONT OUTSIDE THE PINE NUTS.
TUESDAY THROUGH THURSDAY, DRY SOUTHWEST FLOW WILL CONTINUE. ONE
THING TO NOTE IS THAT THERE IS ANOTHER WAVE EMBEDDED IN THE FLOW FOR
TUESDAY THAT COULD BACK THE FLOW TO THE SOUTH OVER MONO/MINERAL AND
KEEP THUNDERSTORMS POSSIBLE THERE. THE EC IS SHOWING THIS IDEA,
WHILE THE GFS IS DRY. WILL KEEP TUESDAY DRY FOR NOW UNTIL THERE IS
MORE CONSISTENCY.
AS FOR THE WINDS, THEY LOOK TO BE FAIRLY TYPICAL FOR MIDSUMMER WITH
AN AFTERNOON/EVENING ZEPHYR EACH DAY AND GUSTS 25-30 MPH.
TEMPERATURES WILL ALSO COOL BACK CLOSER TO AVERAGE IF NOT A LITTLE
BELOW. WALLMANN
&&
.AVIATION...
VFR CONDITIONS AS MONSOONAL MOISTURE STREAMS NORTH TODAY WITH
BROKEN MID AND HIGH CLOUDS. A FEW LIGHT SHOWERS POSSIBLE THIS
MORNING WITH ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON
ALONG AND JUST EAST OF THE SIERRA. COVERAGE MAY BE MORE OVER MONO
COUNTY INCLUDING KMMH, BUT THIS WILL BE DEPENDENT ON CLOUD COVER
THIS MORNING. MAIN THREAT WILL BE GUSTY OUTFLOW WINDS 40+ KTS AND
ASSOCIATED WIND SHEAR.
MORE CLOUDS TONIGHT BEFORE A POTENTIAL REPEAT ON SATURDAY. MOISTURE
INCREASES, BUT THE STORM COVERAGE WILL BE DEPENDENT ON CLOUD COVER.
WALLMANN
&&
.FIRE WEATHER...
MAIN CONCERN WILL BE LIGHTNING TODAY WITH STORMS AS MOISTURE
CONTINUES TO INCREASE. CLOUD COVER IS FAIRLY EXTENSIVE THIS
MORNING SO COVERAGE IS LIKELY TO REMAIN ISOLATED. STORMS WILL
START DRY AND BECOME WET/DRY HYBRIDS AS THE DAY PROGRESSES. AS WE
MOVE INTO SATURDAY, MOISTURE WILL CONTINUE TO INCREASE AND EXPECT
HYBRID STORMS THAT DAY. GIVEN THE DRYNESS AND HEAT PRECEDING, IT
COULD BE A POTENTIALLY ACTIVE DAY. HOWEVER, CLOUD COVER LOOKS LIKE
IT MIGHT BE EXTENSIVE THAT WOULD REDUCE THE INSTABILITY AND
COVERAGE OF STORMS. GIVEN THE UNCERTAINTY, WILL NOT ISSUE A FIRE
WEATHER WATCH FOR DRY LIGHTNING.
AS WE MOVE INTO SUNDAY, MORE MOISTURE WILL BE PRESENT AND STORMS
WILL BE SLOW MOVING. AT THAT POINT, HEAVY RAIN WILL BE THE BIGGER
CONCERN ALTHOUGH A FEW STARTS OUTSIDE THE CORES WILL REMAIN
POSSIBLE. HUMIDITY WILL ALSO BE HIGHER TOO WITH MINIMUMS LIKELY TO
REMAIN ABOVE 20% IN WESTERN NV AND 30% IN THE SIERRA. DRY SOUTHWEST
FLOW IS EXPECTED NEXT WEEK WITH A FEW STORMS POSSIBLE MONDAY. WINDS
NEXT WEEK LOOK TO BE TYPICAL ZEPHYRS WITH GUSTS 25-30 MPH. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1019 AM MDT FRI JUL 31 2015
.UPDATE...
ISSUED AT 1013 AM MDT FRI JUL 31 2015
SATELLITE IMAGERY SHOWING SOME CU START TO DEVELOP OVER THE HIGHER
TERRAIN. HRRR AND RAP CONTINUING TO SHOW STORM DEVELOPMENT OVER
THE DIVIDE THROUGH THE AFTERNOON. SOME OF THE STORMS MAY MOVE OFF
THE MOUNTAINS OVER THE FOOTHILLS OF PARK...JEFFERSON AND DOUGLAS
COUNTIES BY THE EARLY EVENING. BIGGEST THREATS WILL BE BRIEF
MODERATE TO HEAVY RAIN WITH THE POSSIBILITY OF SOME SMALL HAIL AND
WIND GUSTS UP TO 45 MPH WITH THE STRONGER STORMS. TEMPERATURES ARE
STILL ON TRACK TO REACH THE UPPER 80S TO LOWER 90S FOR THE PLAINS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 245 AM MDT FRI JUL 31 2015
THE BROAD UPPER HIGH WILL CONTINUE TO SHIFT FURTHER WEST AND
NORTH ACROSS THE GREAT BASIN TODAY. THIS WILL ALLOW SOME
ADDITIONAL MOISTURE TO ALSO SEEP INTO COLORADO WHERE INTEGRATED PW
VALUES HAVE ALREADY INCREASED AROUND A THIRD OF AN INCH IN THE
PAST 12 HOURS OVER THE FRONT RANGE. STILL THOUGH MID LEVEL
INVERSION AROUND 500MB WILL LIMIT CONVECTION THROUGH THIS
AFTERNOON. NAM SEEMS THE MOST BULLISH ON MOISTURE AND STORM
POTENTIAL WHILE THE THE RAP IS THE DRIEST. EXPECT MAJORITY OF
STORMS WILL BE OVER EAST SLOPES AND HIGHER TERRAIN. SOME OF THIS
MAY SPILL OUT OVER THE ADJACENT PLAINS BY LATER THIS AFTERNOON.
NOT MUCH HELP UPSTAIRS AS QG FIELDS SHOWING SOME SUBSIDENCE IN THE
700MB LAYERS AND NEUTRAL FORCING ALOFT. ISOLATED POPS ON THE
PLAINS WITH HIGHER SCATTERED CHANCES IN THE MOUNTAINS SHOULD
SUFFICE. EXPECT TEMPERATURES WILL BE SIMILAR TO THURSDAY READINGS.
CONVECTION WILL DIMINISH DURING THE EVENING HOURS WITH LACK OF ANY
UPPER AIR SUPPORT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 207 AM MDT FRI JUL 31 2015
BY SATURDAY MORNING...A NEGATIVELY TILTED UPPER RIDGE IS STILL OVER
THE WRN CONUS WITH THE 500MB HIGH OVER SERN NEW MEX. AT THE SFC...
BROAD CLOCKWISE CIRCULATION AROUND A STG HIGH IN NWRN ARKANSAS
CONTINUES TO ADVECT INCREASING AMOUNTS OF LOW-LEVEL MOISTURE
NORTHWARD ALONG THE COLORADO/KANSAS BORDER. MEANWHILE THE MID-LEVEL
NWLY FLOW CONTINUES TO DRY ON THE SOUTH SIDE OF AN 80-90KT JET
SEGMENT. BY LATE AFTERNOON...MODELS SHOW A NEARLY NEUTRAL TILT UPPER
RIDGE MIGRATING EASTWARD OVER ERN UTAH/COLORADO CAUSING THE MID-
LEVEL FLOW OVER THE FCST AREA TO BECOME N-NWLY. AT THE SAME TIME
SELY BNDRY LAYER FLOW EAST OF THE MTNS CONTINUES TO TRANSPORT LOW
LEVEL MOISTURE UP INTO THE FCST AREA. MODELS SHOW MEAN LAYER PW
VALUES PUSHING AN INCH ACRS SERN SECTIONS OF THE CWA BY EVENING.
HOWEVER...MOISTURE APPEARS RELATIVELY SHALLOW...CAPPED BY A MUCH
DRIER N-NWLY FLOW ABOVE 650 MBS. OVERNIGHT SELY SFC WINDS ON THE
PLAINS TURN SWLY WHICH FLUSHES OUT SOME OF THE MOISTURE UP ALONG
THE FRONT RANGE.
DRY OUT IS SHORT-LIVED AS THE GFS...SREF AND NAM SHOW A RETURN TO A
MOIST SELY FLOW DURING THE DAY SUNDAY. MODELS SHOW MEAN LAYER PW
VALUES APPROACH 1.25 INCH OVER NRN PORTIONS OF THE I-25 URBAN
CORRIDOR BY LATE AFTERNOON. THIS TIME THE MOISTURE LAYER APPEARS
DEEPER AND WITH LIGHT/VARIABLE TRANSPORT WINDS SLOW STORM MOTIONS
WOULD CONCEIVABLY RESULT IN LOCALLY HEAVY RAINFALL. ALTHOUGH QPF
FIELDS DO NOT INDICATE ANYTHING LIKE THAT HAPPENING APPARENTLY DUE
TO A LACK OF CAPE AND SOME KIND OF FORCING MECHANISM SUCH AS A
FRONTAL BNDRY OR DEEP UPSLOPE FLOW. HOWEVER MODELS INDICATE CAPES IN
THE 1000-1500 J/KG RANGE...AND ON THE NAM AS HIGH AS 2000 J/KG...AND
DECENT LOW-LEVEL CONVERGENCE/SHEAR ALONG THE PALMER DIVIDE. ITS MORE
LIKELY HERE THAT A FEW SUPERCELLS CAPABLE OF HEAVY RAINFALL...HAIL
AND STG GUSTY WINDS WILL FORM AND TRACK EAST-SOUTHEAST ALONG THE
DIVIDE DURING THE LATE AFTERNOON AND EVENING HRS ON SUN. THE SRN
FRONT RANGE FOOTHILLS AND SOUTH PARK IS ANOTHER AREA WHERE THERE`S
AN ELEVATED POTENTIAL FOR T-STORMS AT THIS TIME DUE TO THIS MOIST
AND UNSTABLE SELY FLOW. ACTUALLY THERE`S A GREATER POTENTIAL FOR
STORMS PRODUCING HEAVY RAINFALL IN PARK COUNTY WITH THIS SET UP.
BY SUNDAY NIGHT...THE NAM...GFS AND ECMWF ALL NOW SHOW A MID-LEVEL
SHORTWAVE TROUGH LIFTING NEWRD ACRS THE STATE WITH THE UPPER RIDGE
COLLAPSING AS IT CONTINUES TO SHIFT EAST. WAVE IS FCST TO REACH THE
FRONT RANGE URBAN CORRIDOR BY EARLY MONDAY MORNING. ITS PASSAGE
COULD ENHANCE OR EXTEND SHOWER/T-STORM DEVELOPMENT IN THE HIGH
COUNTRY THROUGH THE LATE EVENING HRS. NOT SURE THIS DISTURBANCE WILL
HAVE MUCH OF AN IMPACT ON AREAS EAST OF THE MTNS OVERNIGHT.
ON MONDAY...MOISTURE...INSTABILITY AND MODEST QG LIFT ASSOCIATED
WITH THE PASSING SHORTWAVE EXPECTED TO PRODUCE MORE CLOUD COVER AND
A SLIGHTLY GREATER CHANCE OF SHOWERS/T-STORMS FOR THE ENTIRE FCST
AREA. MOST MODELS SHOW THIS FEATURE EXITING THE STATE BY EVENING
WITH DRYING AND STABILIZATION IN ITS WAKE AS THE UPPER RIDGE AXIS
MOVES OVERHEAD OVERNIGHT.
TUESDAY SHOULD BE A DRIER AND SLIGHTLY WARMER DAY WITH ANY STORM
DEVELOPMENT RELEGATED TO THE HIGH COUNTRY. ON WEDNESDAY... TEMPS
CONTINUE TO WARM BOTH SFC AND ALOFT...AND HUMIDITIES LOWER WITH
THE UPPER RIDGE AMPLIFYING OVER THE CENTRAL ROCKIES. HOWEVER STILL
CANNOT RULE OUT A FEW LATE DAY GUSTY T-STORMS IN THE HIGH COUNTRY.
BY THURSDAY...MEDIUM RANGE MODELS SHOW THE UPPER RIDGE MOVING OVER
THE GREAT PLAINS PLACING COLORADO UNDER SWLY FLOW ALOFT. COULD SEE
SUBTROPICAL MOISTURE CARRIED NORTH BY THIS FLOW IN TANDEM WITH A
SHORTWAVE TROUGH THAT MODELS SHOW SWINGING OUT OF THE 4-CORNERS
REGION LATE IN THE DAY. AS A RESULT COULD SEE A MODEST INCREASE IN T-
STORM CHANCES MAINLY FOR THE HIGH COUNTRY. OTHERWISE THURSDAY TEMPS
LITTLE CHANGED FROM THE DAY BEFORE.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SATURDAY MORNING)
ISSUED AT 1013 AM MDT FRI JUL 31 2015
VFR EXPECTED FOR THE NEXT 24 HOURS FOR ALL AIRPORTS. A MID LEVEL
BKN DECK WILL FORM WITH INCREASED MOISTURE IN THE AFTERNOON WITH
SOME SHOWERS IN THE VICINITY. WINDS WILL SLOWLY MAKE THEIR WAY TO
THE SE THEN TRANSITION TO DRAINAGE BY THE EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BOWEN
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
246 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 245 AM MDT FRI JUL 31 2015
THE BROAD UPPER HIGH WILL CONTINUE TO SHIFT FURTHER WEST AND
NORTH ACROSS THE GREAT BASIN TODAY. THIS WILL ALLOW SOME
ADDITIONAL MOISTURE TO ALSO SEEP INTO COLORADO WHERE INTEGRATED PW
VALUES HAVE ALREADY INCREASED AROUND A THIRD OF AN INCH IN THE
PAST 12 HOURS OVER THE FRONT RANGE. STILL THOUGH MID LEVEL
INVERSION AROUND 500MB WILL LIMIT CONVECTION THROUGH THIS
AFTERNOON. NAM SEEMS THE MOST BULLISH ON MOISTURE AND STORM
POTENTIAL WHILE THE THE RAP IS THE DRIEST. EXPECT MAJORITY OF
STORMS WILL BE OVER EAST SLOPES AND HIGHER TERRAIN. SOME OF THIS
MAY SPILL OUT OVER THE ADJACENT PLAINS BY LATER THIS AFTERNOON.
NOT MUCH HELP UPSTAIRS AS QG FIELDS SHOWING SOME SUBSIDENCE IN THE
700MB LAYERS AND NEUTRAL FORCING ALOFT. ISOLATED POPS ON THE
PLAINS WITH HIGHER SCATTERED CHANCES IN THE MOUNTAINS SHOULD
SUFFICE. EXPECT TEMPERATURES WILL BE SIMILAR TO THURSDAY READINGS.
CONVECTION WILL DIMINISH DURING THE EVENING HOURS WITH LACK OF ANY
UPPER AIR SUPPORT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 207 AM MDT FRI JUL 31 2015
BY SATURDAY MORNING...A NEGATIVELY TILTED UPPER RIDGE IS STILL OVER
THE WRN CONUS WITH THE 500MB HIGH OVER SERN NEW MEX. AT THE SFC...
BROAD CLOCKWISE CIRCULATION AROUND A STG HIGH IN NWRN ARKANSAS
CONTINUES TO ADVECT INCREASING AMOUNTS OF LOW-LEVEL MOISTURE
NORTHWARD ALONG THE COLORADO/KANSAS BORDER. MEANWHILE THE MID-LEVEL
NWLY FLOW CONTINUES TO DRY ON THE SOUTH SIDE OF AN 80-90KT JET
SEGMENT. BY LATE AFTERNOON...MODELS SHOW A NEARLY NEUTRAL TILT UPPER
RIDGE MIGRATING EASTWARD OVER ERN UTAH/COLORADO CAUSING THE MID-
LEVEL FLOW OVER THE FCST AREA TO BECOME N-NWLY. AT THE SAME TIME
SELY BNDRY LAYER FLOW EAST OF THE MTNS CONTINUES TO TRANSPORT LOW
LEVEL MOISTURE UP INTO THE FCST AREA. MODELS SHOW MEAN LAYER PW
VALUES PUSHING AN INCH ACRS SERN SECTIONS OF THE CWA BY EVENING.
HOWEVER...MOISTURE APPEARS RELATIVELY SHALLOW...CAPPED BY A MUCH
DRIER N-NWLY FLOW ABOVE 650 MBS. OVERNIGHT SELY SFC WINDS ON THE
PLAINS TURN SWLY WHICH FLUSHES OUT SOME OF THE MOISTURE UP ALONG
THE FRONT RANGE.
DRY OUT IS SHORT-LIVED AS THE GFS...SREF AND NAM SHOW A RETURN TO A
MOIST SELY FLOW DURING THE DAY SUNDAY. MODELS SHOW MEAN LAYER PW
VALUES APPROACH 1.25 INCH OVER NRN PORTIONS OF THE I-25 URBAN
CORRIDOR BY LATE AFTERNOON. THIS TIME THE MOISTURE LAYER APPEARS
DEEPER AND WITH LIGHT/VARIABLE TRANSPORT WINDS SLOW STORM MOTIONS
WOULD CONCEIVABLY RESULT IN LOCALLY HEAVY RAINFALL. ALTHOUGH QPF
FIELDS DO NOT INDICATE ANYTHING LIKE THAT HAPPENING APPARENTLY DUE
TO A LACK OF CAPE AND SOME KIND OF FORCING MECHANISM SUCH AS A
FRONTAL BNDRY OR DEEP UPSLOPE FLOW. HOWEVER MODELS INDICATE CAPES IN
THE 1000-1500 J/KG RANGE...AND ON THE NAM AS HIGH AS 2000 J/KG...AND
DECENT LOW-LEVEL CONVERGENCE/SHEAR ALONG THE PALMER DIVIDE. ITS MORE
LIKELY HERE THAT A FEW SUPERCELLS CAPABLE OF HEAVY RAINFALL...HAIL
AND STG GUSTY WINDS WILL FORM AND TRACK EAST-SOUTHEAST ALONG THE
DIVIDE DURING THE LATE AFTERNOON AND EVENING HRS ON SUN. THE SRN
FRONT RANGE FOOTHILLS AND SOUTH PARK IS ANOTHER AREA WHERE THERE`S
AN ELEVATED POTENTIAL FOR T-STORMS AT THIS TIME DUE TO THIS MOIST
AND UNSTABLE SELY FLOW. ACTUALLY THERE`S A GREATER POTENTIAL FOR
STORMS PRODUCING HEAVY RAINFALL IN PARK COUNTY WITH THIS SET UP.
BY SUNDAY NIGHT...THE NAM...GFS AND ECMWF ALL NOW SHOW A MID-LEVEL
SHORTWAVE TROUGH LIFTING NEWRD ACRS THE STATE WITH THE UPPER RIDGE
COLLAPSING AS IT CONTINUES TO SHIFT EAST. WAVE IS FCST TO REACH THE
FRONT RANGE URBAN CORRIDOR BY EARLY MONDAY MORNING. ITS PASSAGE
COULD ENHANCE OR EXTEND SHOWER/T-STORM DEVELOPMENT IN THE HIGH
COUNTRY THROUGH THE LATE EVENING HRS. NOT SURE THIS DISTURBANCE WILL
HAVE MUCH OF AN IMPACT ON AREAS EAST OF THE MTNS OVERNIGHT.
ON MONDAY...MOISTURE...INSTABILITY AND MODEST QG LIFT ASSOCIATED
WITH THE PASSING SHORTWAVE EXPECTED TO PRODUCE MORE CLOUD COVER AND
A SLIGHTLY GREATER CHANCE OF SHOWERS/T-STORMS FOR THE ENTIRE FCST
AREA. MOST MODELS SHOW THIS FEATURE EXITING THE STATE BY EVENING
WITH DRYING AND STABILIZATION IN ITS WAKE AS THE UPPER RIDGE AXIS
MOVES OVERHEAD OVERNIGHT.
TUESDAY SHOULD BE A DRIER AND SLIGHTLY WARMER DAY WITH ANY STORM
DEVELOPMENT RELEGATED TO THE HIGH COUNTRY. ON WEDNESDAY... TEMPS
CONTINUE TO WARM BOTH SFC AND ALOFT...AND HUMIDITIES LOWER WITH
THE UPPER RIDGE AMPLIFYING OVER THE CENTRAL ROCKIES. HOWEVER STILL
CANNOT RULE OUT A FEW LATE DAY GUSTY T-STORMS IN THE HIGH COUNTRY.
BY THURSDAY...MEDIUM RANGE MODELS SHOW THE UPPER RIDGE MOVING OVER
THE GREAT PLAINS PLACING COLORADO UNDER SWLY FLOW ALOFT. COULD SEE
SUBTROPICAL MOISTURE CARRIED NORTH BY THIS FLOW IN TANDEM WITH A
SHORTWAVE TROUGH THAT MODELS SHOW SWINGING OUT OF THE 4-CORNERS
REGION LATE IN THE DAY. AS A RESULT COULD SEE A MODEST INCREASE IN T-
STORM CHANCES MAINLY FOR THE HIGH COUNTRY. OTHERWISE THURSDAY TEMPS
LITTLE CHANGED FROM THE DAY BEFORE.
&&
.AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 207 AM MDT FRI JUL 31 2015
SURFACE TROF OVER DENVER WITH HEALTHY S-SW WINDS OVER DEN/APA AND
NW WINDS AT BJC. WINDS EXPECTED TO TURN SOUTHEAST OVER ENTIRE AREA
THIS AFTERNOON. MOISTURE LEVELS A BIT HIGHER TODAY AND EXPECT
ISOLATED COVERAGE OF STORMS BY LATER THIS AFTERNOON. HOWEVER AREAL
COVERAGE TOO LOW TO MENTION IN TERMINAL FORECASTS FOR NOW. EXPECT
BRIEF RAIN AND GUSTY WINDS WITH ANY POTENTIAL SHOWERS IN THE
AREA.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...ENTREKIN
AREA FORECAST DISCUSSION
NWS MIAMI FL
801 PM EDT SAT AUG 1 2015
.UPDATE...
LATEST IR SATELLITE SHOWS A GOOD AMOUNT OF DEBRIS CLOUDS FROM
EARLIER CONVECTION AS WELL AS DECAYING CONVECTION NORTH OF THE
AREA. THEREFORE WILL KEEP MOSTLY CLOUDY SKIES ACROSS THE AREA
THROUGH THE NIGHT. LATEST HRRR KEEPS SHOWERS AND THUNDERSTORMS
ACROSS THE ATLANTIC WATERS THROUGH MUCH OF THE NIGHT SO KEPT
ONGOING POPS ACROSS THE WATERS WITH DECREASING CHANCES THROUGH THE
NIGHT. UPDATE SENT.
&&
.PREV DISCUSSION... /ISSUED 734 PM EDT SAT AUG 1 2015/
AVIATION...
AFTERNOON SHOWERS/TSTMS HAVE MOVED OFFSHORE AND SHOULD REMAIN OVER
THE ATLANTIC AND GULF WATERS OF SOUTH FLORIDA THROUGH THE NIGHT AS
SURFACE HIGH PRESSURE DRIFTS NORTH ACROSS THE AREA. ERRATIC WINDS
THROUGH ABOUT 01Z ALONG THE EAST COAST AS OUTFLOW BOUNDARIES FROM
EARLIER STORMS WILL PRODUCE LIGHT NW WINDS. OTHERWISE, EXPECT
LIGHT S-SE WINDS OVERNIGHT WITH BKN/OVC MID AND HIGH CLOUDS
PERSISTING. FOR SUNDAY, RIDGE OVER SOUTH FLORIDA WILL LIKELY LEAD
TO A SLIGHTLY EARLIER ONSET OF EAST COAST SEABREEZE. MOVEMENT OF
TSTMS ON SUNDAY WILL BE SLOWER THAN TODAY, AGAIN FOCUSING OVER THE
INTERIOR, FAVORING EAST SIDE OF THE PENINSULA VS WEST. FOR NOW
WILL KEEP VCTS FOR MOST OF SUNDAY AT EAST COAST SITES AND ONLY
VCSH FOR NAPLES. BKN/OVC MID AND HIGH LEVEL CLOUDS WILL LINGER
OVER THE REGION BUT VFR CONDITIONS SHOULD PREVAIL. /MOLLEDA
PREV DISCUSSION... /ISSUED 415 PM EDT SAT AUG 1 2015/
DISCUSSION...
CONVECTION CONTINUES ACROSS THE AREA THIS AFTERNOON WITH SIMILAR
MESOSCALE CONDITIONS AS WAS SEEN YESTERDAY. MORNING SOUNDING
PARAMETERS WERE RELATIVELY SIMILAR. A COUPLE OF EXCEPTIONS ARE
THE MID LEVEL LAPSE RATES AND CAPE VALUES WHICH ARE A BIT LESS
IMPRESSIVE TODAY WHEN COMPARED TO YESTERDAY. NEVERTHELESS...STILL
EXPECT SCATTERED STRONG STORMS ACROSS MUCH OF THE AREA THROUGH THE
LATE AFTERNOON HOURS WITH MOST OF THE CONVECTION EXPECTED TO BE
FOCUSED ACROSS THE INTERIOR AND ATLANTIC COAST WITH GENERAL
SOUTHWEST STEERING FLOW. STORMS WILL BE CAPABLE OF PRODUCING
FREQUENT LIGHTNING...GUSTY WINDS...AND SMALL HAIL. CONVECTION
SHOULD WANE LATER THIS EVENING WITH HEATING LOSS. HOWEVER...COULD
STILL SEE A FEW LINGERING THUNDERSTORMS ACROSS THE WATERS DURING
THE OVERNIGHT HOURS WITH BROAD TROUGHING ACROSS THE FLORIDA
PENINSULA.
TROUGHING ALONG WITH A DEEP MOISTURE AXIS POSITIONED ACROSS
NORTH-CENTRAL FLORIDA WILL BE THE RULE THROUGH THE REMAINDER OF
THE WEEKEND AND INTO THE FIRST PART OF NEXT WEEK. WEAKNESSES
EMBEDDED WITHIN THE TROUGH WILL ENHANCE SHOWER AND THUNDERSTORM
POTENTIAL EACH DAY. BY MONDAY...STEERING FLOW WILL TRANSITION TO A
MORE SOUTHERLY TO SOUTHEASTERLY DIRECTION AS AN H5 LOW ACROSS CUBA
SLIDES TO THE WEST. THIS WILL ALLOW CONVECTION TO BE FOCUSED MORE
ACROSS THE INTERIOR AND GULF COASTAL AREAS THROUGH WEDNESDAY.
MODELS THEN AGREE ON BUILDING DEEP LAYER RIDGING ACROSS THE
WESTERN ATLANTIC FOR THE LATTER HALF OF THE WEEK...POSSIBLY
BRINGING IN SOME SLIGHTLY DRIER AIR BY THE END OF THE WEEK. THIS
HOWEVER SHOULD NOT RENDER ANY MAJOR PATTERN CHANGE FOR THIS TIME
FRAME ASIDE FROM POSSIBLY A SLIGHT DECREASE IN OVERALL AFTERNOON
SHOWER AND THUNDERSTORM COVERAGE.
MARINE... CHANCES FOR SHOWERS AND THUNDERSTORMS WILL PERSIST
ACROSS THE AREA WATERS EACH DAY THROUGH THE PERIOD. SOUTHEASTERLY
SURFACE WINDS AVERAGING AROUND 10 KNOTS SHOULD PREVAIL ACROSS THE
ATLANTIC WATERS THROUGH THE WEEKEND AND INTO NEXT WEEK WITH SEAS
AROUND 2 FEET OR LESS. WINDS ARE EXPECTED TO DECREASE ACROSS THE
GULF WATERS AND BECOME MOSTLY LIGHT AND VARIABLE. EXPECT INCREASED
WINDS AND SEAS IN AND NEAR ANY THUNDERSTORMS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 77 90 77 92 / 30 30 20 50
FORT LAUDERDALE 79 90 79 90 / 30 30 20 40
MIAMI 80 91 78 91 / 20 30 20 50
NAPLES 77 90 78 91 / 10 20 10 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
UPDATE...10/CD
AVIATION...59/RM
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
227 PM EDT FRI JUL 31 2015
.NEAR TERM.../TODAY THROUGH SATURDAY/...
SLOW MOVING COLD FRONT OVER CENTRAL GA HAS SE GA/NE FL IN A MOIST
LOW-MID LEVEL SW FLOW. SCATTERED SHOWERS HAVE FORMED OVER NE FL
EARLY THIS AFTERNOON WITH ACTIVITY EXPECTED TO INCREASE OVER SE GA
BY LATE AFTERNOON/EARLY EVENING AS HRRR MODEL INDICATES. SW WINDS
WILL KEEP EAST COAST SEABREEZE NEAR THE COAST TODAY WITH STORMS
EXPECTED TO STRENGTHEN UPON BOUNDARY COLLISIONS. EXPECT A SIMILAR
SCENARIO ON SATURDAY WITH SCATTERED CONVECTION BECOMING NUMEROUS
LATE AFTERNOON/EVENING NEAR THE EAST COAST. TEMPERATURES WILL BE
NEAR AVERAGE LEVELS THIS WEEKEND.
&&
.SHORT TERM.../SATURDAY NIGHT THROUGH TUESDAY/...
TROUGHING WILL PERSIST ACROSS THE REGION THROUGH MONDAY...PROVIDING
AN ACTIVE WEATHER PATTERN WITH DAILY ROUNDS OF AFTERNOON AND EVENING
SHOWERS AND STORMS. THESE STORMS WILL BE INITIATED BY THE
COMBINATION OF CONVERGENCE ALONG THE TROUGH AND DIURNAL INSTABILITY.
WITH THE INCREASED CLOUD AND RAIN COVERAGE TEMPERATURES WILL BE
A LITTLE BELOW NORMAL THROUGH MONDAY.
THE TROUGH WEAKENS...WITH SLIGHT RIDGING FOR TUESDAY. PRECIPITATION
CHANCES WILL BE A LITTLE LESS AS A RESULT...WITH MAIN INITIATION
SOURCES FOR CONVECTION BEING DIURNAL HEATING AND SEA BREEZE
CONVERGENCE. TEMPERATURES WILL RETURN TO NEAR NORMAL READINGS
FOR TUESDAY.
&&
.LONG TERM.../TUESDAY NIGHT THROUGH FRIDAY/...
WEAK RIDGING WILL PERSIST INTO WEDNESDAY. A TROUGH WILL SETTLE
INTO THE SOUTHEASTERN US ONCE AGAIN THURSDAY...WITH PRECIPITATION
CHANCES INCREASING TOWARD WEEKS END.
TEMPERATURES WILL BE NEAR TO SLIGHTLY ABOVE NORMAL FOR THIS
PERIOD.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL TODAY WITH TEMPO IFR
CONDITIONS IN SHRA/TSRA UNTIL AROUND 00Z. IFR CONDITIONS AGAIN
POSSIBLE LATE TONIGHT AND EARLY SATURDAY MORNING AS LOW CLOUDS
FORM MAINLY BETWEEN 08Z-13Z.
&&
.MARINE...
SW WINDS WILL DOMINATE INTO EARLY NEXT WEEK AS COLD
FRONT STALLS JUST NORTH OF THE AREA. EXCEPTION WILL BE AFTERNOON
SEABREEZES NEAR THE COAST EACH DAY. NOCTURAL WINDS SURGES WILL
LIKELY PRODUCE SCEC CONDITIONS.
RIP CURRENTS: LOW RISK THROUGH THE WEEKEND WITH OFFSHORE WINDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 73 92 73 91 / 40 70 50 40
SSI 75 86 76 89 / 30 60 50 50
JAX 74 88 74 88 / 30 60 50 60
SGJ 73 86 74 86 / 40 60 50 60
GNV 72 87 73 86 / 40 50 50 60
OCF 72 87 73 87 / 40 50 60 60
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
STRUBLE/ZIBURA
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
938 PM EDT SAT AUG 1 2015
.SYNOPSIS...
A STATIONARY FRONT WILL DISSIPATE OVER OR NEAR THE AREA THROUGH
SUNDAY AS HIGH PRESSURE BUILDS IN EARLY NEXT WEEK. AN INLAND LOW
PRESSURE TROUGH WILL THEN DEVELOP BY LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
CONDITIONS WILL FAVOR THE FORMATION AND THEN A SLOW EXPANSION OF
LOW STRATUS AND FOG EARLY SUNDAY. THE RISK FOR FOG WILL BE
HIGHEST ACROSS FAR INTERIOR SOUTHEAST SOUTH CAROLINA AND SOUTHEAST
GEORGIA CLOSEST TO THE WEAK STATIONARY FRONT...WHILE STRATUS IS
MORE LIKELY CLOSER TO THE COAST WHERE INFLUENCES FROM THE
NOCTURNAL LOW-LEVEL JET CURRENTLY ORGANIZING OFF THE GEORGIA
BEACHES WILL BE GREATER. IT IS STILL SOMEWHAT UNCLEAR EXACTLY HOW
WIDESPREAD EITHER ELEMENT WILL BECOME THIS FAR OUT...BUT THE
02/18Z NAM 1000 MB CONDENSATION PRESSURE DEFICIT PROGS WITH
SUPPORT FROM THE LATEST RAP AND 21Z RUN OF THE NCEP TIME-LAGGED
NORTH AMERICAN RAPID REFRESH ENSEMBLE SYSTEM /NARRE-TL/ ARE
CERTAINLY TRENDING TOWARDS A FOGGIER SOLUTION ACROSS THE SOUTHERN
SOUTH CAROLINA MIDLANDS...EAST-CENTRAL GEORGIA AND OUR FAR INLAND
ZONES. WILL INCREASE THE FOG COVERAGE QUALIFIER FROM PATCHY TO
AREAS OF ACROSS THE FAR INLAND TIER OF ZONES WITH PATCHY FOG
ELSEWHERE...EXCEPT SOUTH AND EAST OF A SAVANNAH-LUDOWICI LINE
WHERE NO MENTION OF FOG WILL BE INCLUDED.
THERE CONTINUE TO BE SIGNALS IN THE VARIOUS HIGH RESOLUTION
GUIDANCE THAT ISOLATED TO PERHAPS SCATTERED SHOWERS/TSTMS COULD
REDEVELOP ALONG THE GEORGIA COAST AFTER 3-4 AM AS LOW-LEVEL
JETTING INTENSIFIES AND INTERACTS WILL A MODEST AMOUNT OF
INSTABILITY THAT LINGERS JUST OFFSHORE. THE RAP IS STILL MUCH MORE
EMPHATIC ON THE REDEVELOPMENT OF DEEP CONVECTION PRIOR TO
SUNRISE...WHILE THE H3R IS LESS SO. WILL MAINTAIN 20-40 PERCENT
POPS ROUGHLY ALONG AND SOUTH OF HILTON HEAD-LUDOWICI
LINE...HIGHEST ACROSS COASTAL MCINTOSH COUNTY...WITH DRY
CONDITIONS ELSEWHERE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
SUNDAY THROUGH TUESDAY...OVERALL THE PATTERN WILL NOT CHANGE
APPRECIABLY THROUGH EARLY NEXT WEEK. ALOFT...THE FORECAST AREA WILL
BE POSITIONED ON THE SOUTHERN EXTENT OF TROUGHING ACROSS THE GREAT
LAKES AND NORTHEAST. THIS WILL RESULT IN A RATHER WEAK AND NEBULOUS
NEARLY ZONAL FLOW THROUGH THE PERIOD. AT THE SURFACE...THE NEARLY
STATIONARY FRONT WILL DISSIPATE AND ITS REMNANTS WILL LINGER ALONG
THE COASTLINE SUNDAY AND MONDAY. THIS WILL RESULT IN A RATHER TIGHT
PWAT GRADIENT ACROSS THE FORECAST AREA...RANGING FROM AROUND 1.5
INCHES OR LESS AROUND ALLENDALE TO WELL OVER 2 INCHES OVER THE
ATLANTIC COASTAL WATERS. BY TUESDAY THE DEEP MOISTURE WILL PUSH EVEN
FURTHER OFFSHORE AND MUCH DRIER AIR WILL COVER ALL OF THE REGION.
POPS FOR SUNDAY AND MONDAY ARE FOCUSED ALONG THE COAST AND OVER THE
COASTAL WATERS...WITH FURTHER DECREASING COVERAGE BY TUESDAY. POPS
MAY BE A BIT OVERDONE FURTHER INLAND AT TIMES...BUT IT WOULDN/T
REQUIRE A SIGNIFICANT SHIFT IN THE DEEP MOISTURE AXIS TO WARRANT
RAISING POPS. TEMPERATURES ARE PRETTY SIMILAR TO WHAT THEY HAVE BEEN
FOR THE LAST FEW DAYS. LOW TO MID 90S SUNDAY AND MONDAY WITH A
SLIGHT WARMING TREND BY TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
UPPER SHORTWAVE ENERGY WILL BEGIN MOVING INTO THE SOUTHEAST UNITED
STATES MID TO LATE WEEK WITH A PRONOUNCED SURFACE TROUGH DEVELOPING
INLAND. PWATS WILL RETURN TO A MORE TYPICAL 2" FOR EARLY AUGUST BY
THURSDAY. A COLD FRONT MAY AFFECT THE AREA FRIDAY INTO SATURDAY. WE
HAVE INCREASING POPS DURING THIS PERIOD AND SLIGHTLY MODERATED
TEMPERATURES DUE TO THICKER CLOUD COVER.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
TSTM IMPACTS AT BOTH TERMINALS HAS ENDED. PRIMARY CONCERN
OVERNIGHT IS THE POTENTIAL FOR FOG/STRATUS IMPACTING KCHS/KSAV.
THE RISK FOR LOW STRATUS LOOKS HIGHEST AT KSAV AS LOW-LEVEL
JETTING TAKES HOLD AN INTERACTS WITH RICH LOW-LEVEL MOISTURE WHILE
FOG IS MORE LIKELY AT KCHS. THE DEGREE OF JETTING WILL ULTIMATELY
DETERMINE HOW IMPACTFUL EITHER ELEMENT WILL BECOME AT THE
TERMINALS. WILL CONTINUE TO TAKE A TRENDED YET CONSERVATIVE
APPROACH WITH THE 00Z TAF CYCLE. WILL CALL FOR LOW-END MVFR CIGS
09-14Z WITH VERY LIGHT FOG AT KSAV...WHILE A TEMPO GROUP FOR MVFR
VSBYS FROM 09-12Z WILL BE SHOWN AT KCHS. ADJUSTMENTS WILL MOST
LIKELY BE NEEDED AS TRENDS BECOME MORE APPARENT LATER TONIGHT.
ONCE FOG/STRATUS DISSIPATES...EXPECT VFR CONDITIONS.
EXTENDED AVIATION OUTLOOK...LOW CHANCES FOR DIRECT IMPACTS FROM
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS. ALSO LOW CHANCES FOR
PERIODS OF STRATUS/FOG AROUND SUNRISE.
&&
.MARINE...
TONIGHT...WINDS WILL INCREASE ACROSS THE WATERS TONIGHT AS LOW-
LEVEL JETTING TAKES HOLD. BOTH WINDS AND SEAS COULD GET VERY CLOSE
TO SMALL CRAFT ADVISORY THRESHOLDS OVER THE THE FAR EASTERN
PORTIONS OF THE GEORGIA OFFSHORE ZONE...BUT THE DURATION OF SUCH
CONDITIONS LOOK TO BE ABOUT 3-4 HOURS AT BEST. GIVEN THE
RELATIVELY SMALL AREA IMPACTED...WILL CAP BOTH WINDS AND SEAS AT
20 KT AND SEAS 5 FT...OR JUST BELOW SMALL CRAFT ADVISORY
THRESHOLDS...AND NOT HOIST AN ADVISORY WITH THIS FORECAST CYCLE.
SUNDAY THROUGH THURSDAY...THE LINGERING WEAK FRONT WILL DISSIPATE
ALONG THE COAST ON SUNDAY AND SOUTHWEST FLOW WILL GENERALLY PREVAIL
ACROSS THE LOCAL WATERS THROUGH THE MIDDLE OF NEXT WEEK. AS AN
INLAND TROUGH OF LOW PRESSURE DEVELOPS...THE PRESSURE GRADIENT WILL
TIGHTEN AT TIMES AND LEAD TO PERIODS OF SURGING IN THE SOUTHWEST
FLOW. WIND SPEEDS WILL GENERALLY TOP OUT IN THE 15-20 KT RANGE...BUT
COULD MARGINALLY APPROACH SMALL CRAFT ADVISORY CRITERIA AT TIMES.
SEAS WILL INCREASE IN THE IMPROVING SOUTHWEST FETCH AS
WELL...INCREASING TO 2-4 FT WITHIN 20 NM AND MAINLY 4-5 FT BEYOND. 6
FT SEAS COULD BEGIN ACROSS THE OUTER GEORGIA WATERS STARTING MONDAY
AND A SMALL CRAFT ADVISORY COULD BE NEEDED.
&&
.TIDES/COASTAL FLOODING...
TIDES WILL REMAIN ELEVATED THROUGH SUNDAY...BUT THEREAFTER WILL
BEGIN TO DECREASE AS WE MOVE FURTHER AWAY FROM THE FULL MOON AND
PERIGEE. SHALLOW COASTAL FLOODING APPEARS UNLIKELY AFTER SUNDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
742 PM EDT SAT AUG 1 2015
.SYNOPSIS...
A STATIONARY FRONT WILL DISSIPATE OVER THE AREA THROUGH SUNDAY AS
HIGH PRESSURE BUILDS IN EARLY NEXT WEEK. AN INLAND LOW PRESSURE
TROUGH WILL THEN DEVELOP BY LATE NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MOST OF THE MEASURABLE RAINFALL HAS ENDED FOR THIS EVENING. A FEW
LINGERING SHOWERS WILL IMPACT PARTS OF LONG AND TATTNALL COUNTIES
THROUGH 8 PM. EXPECT DRY CONDITIONS TO PREVAIL FOR THE REST OF
THE NIGHT FOR MOST AREAS. THERE ARE SIGNALS IN THE VARIOUS HIGH
RESOLUTION GUIDANCE THAT ISOLATED TO PERHAPS SCATTERED SHOWERS/TSTMS
COULD REDEVELOP ALONG THE GEORGIA COAST AFTER 3-4 AM AS LOW-LEVEL
JETTING INTENSIFIES AND INTERACTS WILL A MODEST AMOUNT OF
INSTABILITY THAT LINGERS JUST OFFSHORE. THE RAP IS MUCH MORE
EMPHATIC ON THE REDEVELOPMENT OF DEEP CONVECTION PRIOR TO
SUNRISE...WHILE THE H3R IS LESS SO. WILL SHOW POPS INCREASING TO
20-40 PERCENT DURING THIS TIME ROUGHLY ALONG AND SOUTH OF HILTON
HEAD-LUDOWICI LINE...HIGHEST ACROSS COASTAL MCINTOSH COUNTY...WITH
DRY CONDITIONS ELSEWHERE TO TREND. IF THE H3R BEGINS TO COME MORE
IN LINE WITH THE LATEST RAP...THEN AN INCREASE IN POPS MAY BE IN
ORDER LATER THIS EVENING.
CONDITIONS WILL FAVOR THE FORMATION AND SLOW EXPANSION OF LOW
STRATUS AND FOG EARLY SUNDAY AS LOW-LEVEL JETTING TAKES HOLD. THE
RISK FOR FOG WILL BE HIGHEST ACROSS INTERIOR SOUTHEAST SOUTH
CAROLINA CLOSEST TO THE WEAK STATIONARY FRONT...WHILE STRATUS IS
MORE LIKELY FAR SOUTH AND CLOSER TO THE COAST. IT IS UNCLEAR
EXACTLY HOW WIDESPREAD EITHER ELEMENT WILL BECOME THIS FAR OUT SO
ADJUSTMENTS WILL LIKELY BE NEEDED THROUGHOUT THE NIGHT AS TRENDS
BECOME MORE APPARENT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
SUNDAY THROUGH TUESDAY...OVERALL THE PATTERN WILL NOT CHANGE
APPRECIABLY THROUGH EARLY NEXT WEEK. ALOFT...THE FORECAST AREA WILL
BE POSITIONED ON THE SOUTHERN EXTENT OF TROUGHING ACROSS THE GREAT
LAKES AND NORTHEAST. THIS WILL RESULT IN A RATHER WEAK AND NEBULOUS
NEARLY ZONAL FLOW THROUGH THE PERIOD. AT THE SURFACE...THE NEARLY
STATIONARY FRONT WILL DISSIPATE AND ITS REMNANTS WILL LINGER ALONG
THE COASTLINE SUNDAY AND MONDAY. THIS WILL RESULT IN A RATHER TIGHT
PWAT GRADIENT ACROSS THE FORECAST AREA...RANGING FROM AROUND 1.5
INCHES OR LESS AROUND ALLENDALE TO WELL OVER 2 INCHES OVER THE
ATLANTIC COASTAL WATERS. BY TUESDAY THE DEEP MOISTURE WILL PUSH EVEN
FURTHER OFFSHORE AND MUCH DRIER AIR WILL COVER ALL OF THE REGION.
POPS FOR SUNDAY AND MONDAY ARE FOCUSED ALONG THE COAST AND OVER THE
COASTAL WATERS...WITH FURTHER DECREASING COVERAGE BY TUESDAY. POPS
MAY BE A BIT OVERDONE FURTHER INLAND AT TIMES...BUT IT WOULDN/T
REQUIRE A SIGNIFICANT SHIFT IN THE DEEP MOISTURE AXIS TO WARRANT
RAISING POPS. TEMPERATURES ARE PRETTY SIMILAR TO WHAT THEY HAVE BEEN
FOR THE LAST FEW DAYS. LOW TO MID 90S SUNDAY AND MONDAY WITH A
SLIGHT WARMING TREND BY TUESDAY.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
UPPER SHORTWAVE ENERGY WILL BEGIN MOVING INTO THE SOUTHEAST UNITED
STATES MID TO LATE WEEK WITH A PRONOUNCED SURFACE TROUGH DEVELOPING
INLAND. PWATS WILL RETURN TO A MORE TYPICAL 2" FOR EARLY AUGUST BY
THURSDAY. A COLD FRONT MAY AFFECT THE AREA FRIDAY INTO SATURDAY. WE
HAVE INCREASING POPS DURING THIS PERIOD AND SLIGHTLY MODERATED
TEMPERATURES DUE TO THICKER CLOUD COVER.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
TSTM IMPACTS AT BOTH TERMINALS HAS ENDED. PRIMARY CONCERN
OVERNIGHT IS THE POTENTIAL FOR FOG/STRATUS IMPACTING KCHS/KSAV.
THE RISK FOR LOW STRATUS LOOKS HIGHEST AT KSAV AS LOW-LEVEL
JETTING TAKES HOLD AN INTERACTS WITH RICH LOW-LEVEL MOISTURE WHILE
FOG IS MORE LIKELY AT KCHS. THE DEGREE OF JETTING WILL ULTIMATELY
DETERMINE HOW IMPACTFUL EITHER ELEMENT WILL BECOME AT THE
TERMINALS. WILL CONTINUE TO TAKE A TRENDED YET CONSERVATIVE
APPROACH WITH THE 00Z TAF CYCLE. WILL CALL FOR LOW-END MVFR CIGS
09-14Z WITH VERY LIGHT FOG AT KSAV...WHILE A TEMPO GROUP FOR MVFR
VSBYS FROM 09-12Z WILL BE SHOWN AT KCHS. ADJUSTMENTS WILL MOST
LIKELY BE NEEDED AS TRENDS BECOME MORE APPARENT LATER TONIGHT.
ONCE FOG/STRATUS DISSIPATES...EXPECT VFR CONDITIONS.
EXTENDED AVIATION OUTLOOK...LOW CHANCES FOR DIRECT IMPACTS FROM
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS. ALSO LOW CHANCES FOR
PERIODS OF STRATUS/FOG AROUND SUNRISE.
&&
.MARINE...
TONIGHT...VARIABLE WINDS THIS AFTERNOON TO BECOME SOUTHWEST AND
STRENGTHEN THIS EVENING AS THE LOW-LEVEL JET INTENSIFIES AHEAD OF
LOW PRESSURE OVER THE WESTERN FLORIDA PANHANDLE. THERE IS A
CHANCE THAT SMALL CRAFT ADVISORY CONDITIONS DEVELOP OVER EASTERN
PORTION OF THE OUTER GEORGIA WATERS CLOSER TO THE GULF STREAM BUT
FOR NOW WE KEPT CONDITIONS JUST BELOW SUCH LEVELS /20 KT AND 5
FT/.
SUNDAY THROUGH THURSDAY...THE LINGERING WEAK FRONT WILL DISSIPATE
ALONG THE COAST ON SUNDAY AND SOUTHWEST FLOW WILL GENERALLY PREVAIL
ACROSS THE LOCAL WATERS THROUGH THE MIDDLE OF NEXT WEEK. AS AN
INLAND TROUGH OF LOW PRESSURE DEVELOPS...THE PRESSURE GRADIENT WILL
TIGHTEN AT TIMES AND LEAD TO PERIODS OF SURGING IN THE SOUTHWEST
FLOW. WIND SPEEDS WILL GENERALLY TOP OUT IN THE 15-20 KT RANGE...BUT
COULD MARGINALLY APPROACH SMALL CRAFT ADVISORY CRITERIA AT TIMES.
SEAS WILL INCREASE IN THE IMPROVING SOUTHWEST FETCH AS
WELL...INCREASING TO 2-4 FT WITHIN 20 NM AND MAINLY 4-5 FT BEYOND. 6
FT SEAS COULD BEGIN ACROSS THE OUTER GEORGIA WATERS STARTING MONDAY
AND A SMALL CRAFT ADVISORY COULD BE NEEDED.
&&
.TIDES/COASTAL FLOODING...
CURRENT TIDE TRENDS SUGGEST LEVELS COULD GET IN THE 6.9-7.0 FT
MLLW RANGE AT THE CHARLESTON HARBOR WITH HIGH TIDE THIS EVENING.
NOT YET CONFIDENT ENOUGH THAT 7.0 FT ADVISORY CRITERIA WILL BE
BREACHED...SO HAVE ISSUED A COASTAL FLOOD STATEMENT TO ADDRESS
VERY MINOR FLOODING ISSUES THAT ARE KNOWN TO OCCUR IN DOWNTOWN
CHARLESTON WITH TIDES FALLING JUST SHORT OF 7.0 FT MLLW. THE NEED
FOR A COASTAL FLOOD ADVISORY CONTINUES TO BE EVALUATED.
TIDES WILL REMAIN ELEVATED THROUGH SUNDAY...BUT THEREAFTER WILL
BEGIN TO DECREASE AS WE MOVE FURTHER AWAY FROM THE FULL MOON AND
PERIGEE. SHALLOW COASTAL FLOODING APPEARS UNLIKELY AFTER SUNDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.
&&
$$
ST
AREA FORECAST DISCUSSION
NWS LINCOLN IL
317 PM CDT FRI JUL 31 2015
.SHORT TERM...(TONIGHT)
ISSUED AT 315 PM CDT FRI JUL 31 2015
19Z/2PM SURFACE ANALYSIS SHOWS WEAK COLD FRONT SETTLING INTO CENTRAL
ILLINOIS...EXTENDING FROM NEAR RANTOUL TO JUST SOUTH OF QUINCY.
MINIMAL CONVERGENCE ALONG THE FRONT AND AN OVERALL LACK OF DEEP
LAYER MOISTURE HAS LARGELY PREVENTED CONVECTION. THE EXCEPTION HAS
BEEN FURTHER NORTHEAST ACROSS NORTHERN INDIANA WHERE A FEW CLUSTERS
OF THUNDERSTORMS HAVE DEVELOPED. HRRR CONTINUES TO OVER-EMPHASIZE
DEWPOINT POOLING ALONG THE FRONT AND PRODUCES NUMEROUS THUNDERSTORMS
WITH ITS 1 AND 2-HOUR FORECAST. MEANWHILE...THE RAPID REFRESH HAS
CONSISTENTLY PRESENTED A MORE REALISTIC SCENARIO...SUGGESTING ONLY
ISOLATED STORMS MAINLY ACROSS THE E/NE KILX CWA OVER THE NEXT 2-4
HOURS. GIVEN THIS IS THE LOCATION WHERE CU-FIELD IS CURRENTLY MOST
PRONOUNCED...WILL CONTINUE TO FOLLOW THIS SOLUTION CLOSELY. AS A
RESULT...WILL CARRY SLIGHT CHANCE POPS ALONG/NORTHEAST OF A
CHAMPAIGN TO MARSHALL LINE THROUGH THE AFTERNOON. ANY ISOLATED
CONVECTION THAT DEVELOPS WILL QUICKLY DISSIPATE TOWARD
SUNSET...FOLLOWED BY MOSTLY CLEAR AND DRY CONDITIONS TONIGHT.
SLIGHTLY DRIER AIRMASS WILL TRICKLE IN FROM THE NORTHWEST ONCE THE
FRONT PASSES...WITH OVERNIGHT LOW TEMPERATURES DROPPING INTO THE
LOWER TO MIDDLE 60S.
&&
.LONG TERM...(SATURDAY THROUGH FRIDAY)
ISSUED AT 315 PM CDT FRI JUL 31 2015
OVERALL A FAIRLY PERSISTENT WNW FLOW PATTERN WILL REMAIN ACROSS IL
AND MUCH OF THE MIDWEST THROUGH THE WEEKEND AND INTO EARLY NEXT
WEEK. QUITE A BIT OF MODEL UNCERTAINTY REGARDING A BREAKDOWN OF THE
WESTERN RIDGE AND DEEPENING OF THE EASTERN TROUGH FOR THE MIDDLE OF
NEXT WEEK.
IN THE NEAR TERM...VERY WARM AND INCREASINGLY HUMID CONDITIONS WILL
BE ON TAP FOR CENTRAL AND EASTERN IL SATURDAY. AN ADVANCING WARM
FRONT AND A CLUSTER OF CONVECTION FROM IOWA/NEBRASKA IS EXPECTED TO
APPROACH AREAS WEST OF THE IL RIVER VALLEY LATE SATURDAY NIGHT AND
INTO SUNDAY MORNING. THE REMNANTS OF THE EARLY MORNING T-STORMS ARE
THEN EXPECTED TO SPREAD ACROSS MOST OF CENTRAL AND EASTERN IL SUNDAY
MORNING AND EARLY AFTERNOON. RESIDUAL BOUNDARIES FROM THIS
CONVECTION SHOULD RESULT IN REDEVELOPMENT OF T-STORMS SUNDAY
AFTERNOON AND INTO THE EVENING...ESPECIALLY ALONG AND NORTH OF I-74.
SOME OF THE STORMS LATER IN THE DAY SUNDAY COULD BE STRONG...MAINLY
DUE TO MODERATE LEVELS OF WIND SHEAR AND INSTABILITY.
MOST OF THE FORECAST AREA WILL BE IN THE WARM SECTOR OF AN ADVANCING
FRONTAL BOUNDARY...YIELDING VERY WARM AND SOMEWHAT HUMID CONDITIONS
MONDAY. THE AFOREMENTIONED FRONT IS EXPECTED TO SLOWLY MOVE INTO
CENTRAL ILLINOIS MONDAY NIGHT AND THEN REMAIN NEARLY STATIONARY FOR
MUCH OF THE WEEK. THIS SHOULD RESULT IN A RATHER UNSETTLED WEATHER
PATTERN WITH THE POTENTIAL FOR SEVERAL PERIODS OF RAIN FROM LATE
MONDAY...ON AND OFF...THROUGH THE END OF THE WEEK.
THE UNCERTAINTY IN THE MODELS REVOLVES AROUND THE DETAILS OF
POSSIBLE SHORTWAVE ENERGY BREAKING THROUGH THE WESTERN U.S. RIDGE
AND INTERACTING WITH THE FRONT. THE GFS IS A BIT MORE AGGRESSIVE WITH
THIS THAN THE EUROPEAN MODEL. HOWEVER...THE EUROPEAN NOT ONLY
UNDERPLAYS THE AFFECTS OF THIS BUT KEEPS THE SURFACE FRONT FARTHER
NORTH. UNTIL THE DETAILS ARE WORKED OUT IT IS HARD TO PIN DOWN
WHERE A THREAT OF PERSISTENT...POSSIBLY HEAVY RAIN MAY SET UP THE
MIDDLE OF NEXT WEEK. THUS...WILL NOT MAKE TOO MANY MAJOR CHANGES
TO THE FORECAST AND KEEP CHANCE POPS FOR THUNDERSTORMS ACROSS A
LARGE PART OF THE FORECAST AREA.
THE ONE THING THE MODELS DO AGREE ON IS THAT WITH THE PERIODS OF
CONVECTION AND RESIDUAL CLOUD COVER...TEMPERATURES SHOULD BE BELOW
SEASONAL NORMALS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1255 PM CDT FRI JUL 31 2015
WEAK COLD FRONT CONTINUES TO SAG SOUTHWARD INTO NORTH-CENTRAL
ILLINOIS EARLY THIS AFTERNOON. CU-FIELD REMAINS LARGELY ABSENT
ALONG THE BOUNDARY THUS FAR...EXCEPT ACROSS NORTHERN INDIANA INTO
NORTHEAST ILLINOIS. THIS CLOUD TREND FITS VERY WELL WITH THE RAPID
REFRESH...WHICH SHOWS WIDELY SCATTERED CONVECTION DEVELOPING
ACROSS THIS AREA OVER THE NEXT COUPLE OF HOURS...WHILE KEEPING THE
REMAINDER OF THE FRONTAL BOUNDARY TOTALLY DRY. AS A RESULT...WILL
ONLY MENTION VCTS AT KCMI BETWEEN 18Z AND 22Z. FEW-SCT DIURNAL
CLOUDS ALONG/AHEAD OF THE FRONT WILL QUICKLY DISSIPATE TOWARD
SUNSET...WITH CLEAR SKIES EXPECTED TONIGHT THROUGH SATURDAY
MORNING. WINDS WILL INITIALLY BE FROM THE NORTHWEST GUSTING TO
BETWEEN 15 AND 18KT THIS AFTERNOON...THEN WILL BECOME WESTERLY AT
LESS THAN 5KT TONIGHT.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BARNES
LONG TERM...MILLER
AVIATION...BARNES
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1129 PM CDT THU JUL 30 2015
.UPDATE...
ISSUED AT 1126 PM CDT THU JUL 30 2015
HAVE ADDED ISOLATED STORM WORDING FAR SW SECTIONS EARLY FRI
MORNING FOR A FEW HOURS. CONVECTION CONTINUES TO CYCLE ACROSS ERN
NE AND JUST WILL NOT GO AWAY. LATEST SPC MESOANALYSIS SHOWS 1-2K
J/KG MUCAPES WITH LESS THAN 50 J/KG CINHS IN ZONE OF INCREASING
H85/H7 THETA-E ADVECTION. SEEMS TO BE SOME KINEMATIC CONTRIBUTION
AS WELL DUE TO LIFT WELL AHEAD OF FAR NRN ND/MN SHORT WAVE NOTED
IN WATER VAPOR IMAGERY. STORMS COULD JUST TOUCH STRONG LIMITS AT
TIMES WITH 30KTS OF EFFECTIVE SHEAR AND DECENT DCAPES.
&&
.SHORT TERM /TONIGHT/...
ISSUED AT 357 PM CDT THU JUL 30 2015
SURFACE HIGH WILL REMAIN IN PLACE OVER FAR SOUTHERN IOWA TONIGHT
WHILE ALOFT WE WILL REMAIN IN NORTHWEST FLOW. THE NAM IS SUGGESTING
A SUBTLE SHORTWAVE CROSSING SOUTHWEST IOWA OVERNIGHT AS A WEAK COLD
FRONT SINKS INTO THE NORTHWEST QUARTER OR SO OF THE STATE. THERE IS
SOME POSSIBILITY THAT A SPRINKLE OR TWO COULD BE ASSOCIATED WITH
EITHER OF THESE FEATURES BUT INSTABILITY IS RATHER MINIMAL AND
FORCING IS TIED MORE TO THE FRONTAL BOUNDARY THAN THE SUBTLE WAVE
ACROSS THE SOUTH...WHERE THE BETTER INSTABILITY LIES. CONFIDENCE AS
TO WHERE ANY PRECIP MAY OCCUR IS VERY LOW AND AS SUCH I DO NOT HAVE
A MENTION OF POPS IN THE FORECAST. HI-RES CONVECTION ALLOWING
MODELS ARE IN POOR AGREEMENT AS WELL AS THE HRRR CURRENTLY IS
FORECASTING SHOWERS ACROSS THE NORTHERN HALF OF IOWA WHERE THERE ARE
BARELY A FEW CLOUDS. THE NAM 12 HAS SPITS OF PRECIP OVER BOTH THE
SOUTH AND NORTHWEST WHILE THE OTHER MODELS DO THIS OVER THE SOUTH.
COVERAGE WOULD BE SPARSE AND POPS MAY NEED TO BE ADJUSTED IN LATER
SHIFTS IF SOMETHING IS ABLE TO DEVELOP. AS FOR TEMPS...NORTHWEST
IOWA SHOULD BE THE COOLEST AS THE FRONT WILL BE THROUGH THEM BUT IT
IS DOUBTFUL THAT IT WILL MAKE IT TOO FAR INTO OUR FORECAST AREA BY
12Z. AS A RESULT I HAVE KEPT LOWER 60S NORTH TO MID 60S SOUTH FOR
TONIGHT`S LOWS.
.LONG TERM /FRIDAY THROUGH THURSDAY/...
ISSUED AT 357 PM CDT THU JUL 30 2015
GENERAL PREMISE OF LONG TERM LOOKING SIMILAR TO YESTERDAY/S OUTPUT.
DIFFERENCE IS THAT TODAY/S RUNS ARE A LITTLE MORE AMPLIFIED AND
CONFIDENCE INCREASED IN MULTIPLE ROUND OF PRECIP OF THE NEXT SEVEN
DAYS. FROM 12Z UNTIL 18Z FRIDAY...A WEAK BOUNDARY WILL BE PASSING
THROUGH OUR CWA FROM NW TO SE. PWATS WITH THIS BOUNDARY BARELY GO
ABOVE 1 INCH AND MOISTURE CONV AT THE SFC IS MINIMAL. TIME OF DAY
ALSO TYPICALLY NOT FAVORABLE FOR CONVECTION. THEREFORE...AM
KEEPING CWA DRY WITH THIS BOUNDARY PASSAGE. EXPECT ANOTHER MAINLY
CLOUD- FREE DAY WITH 850MB TEMPS IN THE 17C TO 20C RANGE TO MIX
DOWN AND YIELD MID TO UPPER 80S.
FRIDAY EVENING INTO SATURDAY MORNING...THE AFOREMENTIONED BOUNDARY
LOOKS TO LINGER IN NORTHERN MISSOURI TO NORTHEASTERN NEBRASKA AND
WILL SERVE AS THE FOCUSING MECHANISM FOR EVENING
CONVECTION...ESPECIALLY IN NORTHEASTERN NEBRASKA. CORFIDI VECTORS
SUGGEST STORM MOVEMENT WILL BE TO THE SE...WITH ANY RIGHT-MOVERS
MOVING MORE SOUTHERLY. WITH ENOUGH INSTABILITY PRESENT IN SOUTHERN
IOWA AHEAD OF THESE STORMS...IT SEEMS PLAUSIBLE ANY OUTFLOW
BOUNDARIES WILL PROPAGATE IN A NE/E DIRECTION INTO SOUTHERN
IOWA...POSSIBLY CLIPPING OUR SW COUNTIES. THEREFORE HAVE SOME
SLIGHT POPS GOING IN OUR SOUTH WHICH CAN OBVIOUSLY BE TWEAKED IN
NEXT UPDATES.
SATURDAY LOOKS TO BE DRY...BUT THE NEXT PRECIP CHANCES FOR ARRIVE
LATE EVENING INTO THE OVERNIGHT PERIOD FOR SUNDAY MORNING. MODELS
NOW VERY CONSISTENT IN PRODUCING A SIZABLE MCS OVER SE SOUTH DAKOTA
AND PROPAGATING THIS MCS SOUTHEASTWARD THROUGH THE CENTRAL TO
WESTERN PORTIONS OF OUR CWA. GFS SEEMING TO BE A FAST OUTLIER...SO
LEANED AWAY FROM IT FOR TIMING PURPOSES. AM STARTING TO SEE HEAVY
RAINFALL SIGNATURE AS SHORT TERM MODELS PLACING A SLUG OF 2 TO 2.25
INCH PWATS WITH THIS MCS...MIXING RATIOS OVER 8 J/KG...AND 0 TO 6 MU
CAPE OVER 1500 J/KG. IN FACT THE 18Z NAM HAD PWATS OVER 2.5
INCHES...SO RECENT MODEL TRENDS CERTAINLY POINTING UPWARDS.
BEYOND SUNDAY...YESTERDAY/S LONG TERM MODELS HINTED AT A
BAROCLINIC ZONE TRYING TO ESTABLISH ITSELF OVER OUR SOUTHERN CWA
THROUGH MID WEEK. REGION TO REMAIN IN WESTERLY TO NORTHWESTERLY
FLOW ALOFT...SUGGESTING AN OVERALL PATTERN OF SHORTWAVE
PROPAGATION THROUGH IOWA. TODAY/S MODEL RUNS YIELD A SIMILAR
SETUP TO YESTERDAY/S...WITH THE MAIN DIFFERENCE BEING HIGHER PWATS
IN THE 1.5 INCH RANGE OR SO OVER MUCH OF OUR CWA. THUS...HAVE
INCREASED POPS FURTHER NORTH FROM YESTERDAY AND UPPED CONFIDENCE
SLIGHTLY. INTERESTING THAT THE GFS...WHICH OFTEN HAS A DRY
BIAS...IS PRODUCING SO MUCH MOISTURE IN IOWA. IF UPWARD TREND
CONTINUES...NEXT WEEK COULD BE WET. WITH EXPECTED CLOUD
COVER...BEGUN TO TRIM DIURNAL RANGE...SLIGHTLY LOWERING MAX TEMPS
AND INCREASING MIN TEMPS.
&&
.AVIATION...31/06Z
ISSUED AT 1126 PM CDT THU JUL 30 2015
UNLESS CONDITIONS CHANGE SOON...EXPECT VFR CONDITIONS ACROSS TAFS
AND NO THUNDER WITH ERN NE CONVECTION STAYING SW OF SITES.
CONVECTION SEEMS TO HAVE CYCLED DOWN AND THEN BACK OUT OF NOWHERE
RECENTLY HOWEVER...SO CONFIDENCE IN THAT HAS DECREASED SOMEWHAT.
OTHERWISE EXPECT NOTHING MORE THAN SCT MID CLOUDS AND GENERALLY
LIGHT WINDS EVENTUALLY VEERING TO NWLY DURING FRI PEAK HEATING
MIXING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...SMALL
SHORT TERM...FAB
LONG TERM...KOTENBERG
AVIATION...SMALL
...UPDATE TO AVIATION FORECAST DISCUSSION AND NEAR TERM CONVECTIVE
FORECAST...
.UPDATE...
ISSUED AT 715 PM CDT SAT AUG 1 2015
ISOLATED THUNDERSTORMS HAVE BEEN ABLE TO DEVELOP NEAR CNK AND
ALSO EMP IN AREAS OF WEAK CONVERGENCE. A FEW MORE STORMS MAY
DEVELOP MAINLY IN THE AREA NEAR/SOUTH OF I-35 AND WILL BE CLOSELY
WATCHING WELL FORMED OUTFLOW BOUNDARIES MOVING WEST INTO EASTERN
KANSAS. HOWEVER...WHILE LOW LEVEL LAPSE RATES ARE STEEP, THE MID
LEVELS HAVE VERY WEAK LAPSE RATES ALONG WITH DRY AIR. VISUAL
APPEARANCE OF CB NEAR EMP/UKL ARE INDICATIVE OF THIS WEAKNESS IN
THE MID LEVEL BUOYANCY AND EXPECT ANY FURTHER TS DEVELOPMENT TO BE
POSSIBLE...BUT TO STRUGGLE TO ORGANIZE IN ANY WAY.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
19Z WATER VAPOR IMAGERY SHOWS NORTHWEST FLOW ACROSS THE NORTHERN AND
CENTRAL PLAINS WHILE THE CENTER OF A MID LEVEL RIDGE SITS OVER WEST
TX. THE RIDGE AXIS EXTENDED NORTHWEST INTO OR. THE RAP ANALYSIS
SUGGESTS THERE ARE ONLY A COUPLE WEAK VORT MAXIMUM UPSTREAM. ONE
OVER EASTERN NEB AND ANOTHER MOVING INTO SD. AT THE SURFACE, A MESO
HIGH REMAIN OVER CENTRAL NEB WHILE OUTFLOW BOUNDARIES FROM MORNING
CONVECTION HAVE BECOME MORE DIFFUSE ACROSS CENTRAL AND EASTERN KS.
FOR THIS AFTERNOON AND THIS EVENING, THERE REMAINS AN OUTSIDE CHANCE
FOR A STORM TO DEVELOP AS OBJECTIVE ANALYSIS SHOWS MORE THAN ENOUGH
INSTABILITY. HOWEVER SURFACE FLOW HAS BEEN RATHER WEAK SO
CONVERGENCE AND LIFT ALONG ANY OF THE BOUNDARIES HAS ALSO BEEN
RATHER WEAK. SATELLITE SHOWS LITTLE DEVELOPMENT TO THE CU FIELD
ACROSS THE AREA INDICATING THERE HASN`T BEEN MUCH FORCING AS WELL.
AND ANY WEAK VORTICITY ADVECTION FROM THE LEFT OVER CONVECTION IN
EASTERN NEB IS LIKELY PROPAGATING INTO MO. BECAUSE OF THIS THINK THE
CHANCES FOR ANY SPOT TO RECEIVE RAIN IS ONLY ABOUT 10 PERCENT AND
NOT HIGH ENOUGH TO MENTION IN THE FORECAST. ONCE THE BOUNDARY LAYER
STARTS TO COOL, THE THREAT FOR THUNDERSTORMS SHOULD DIMINISH.
OVERNIGHT, MODELS SHOW THE LOW LEVEL JET SETTING UP ACROSS NEB AND
IA WITH NO REAL ORGANIZED ISENTROPIC LIFT ACROSS THE FORECAST AREA.
BECAUSE OF THIS HAVE A DRY FORECAST GOING THROUGH THE NIGHT. THERE
SHOULD BE MOSTLY CLEAR SKIES, SO THINK WITH SOME RADIATIONAL COOLING
LOWS WILL FALL INTO THE UPPER 60S TO AROUND 70.
FOR SUNDAY, THE SETUP LOOKS VERY SIMILAR TO TODAY WITH DECENT
SURFACE BASED INSTABILITY DEVELOPING AND NOT MUCH INHIBITION TO
CONVECTION. WITH A LACK OF LARGE SCALE FORCING, PRECIP CHANCES LOOK
UNLIKELY UNTIL A TROUGH AXIS APPROACHES NORTH CENTRAL KS LATE IN THE
DAY. MOST MODEL SOLUTIONS SHOW THIS BOUNDARY MOVING INTO THE
FORECAST AREA LATE IN THE AFTERNOON BUT THE GFS IS REALLY THE ONLY
ONE THAT DEVELOPS CONVECTION. THE GFS ALSO IS THE WARMEST SOLUTION
AND MAY BE A LITTLE EAGER TO BREAK WHAT CAP THERE IS. WHILE PRECIP
CHANCES DON`T LOOK GREAT, IT`S DIFFICULT TO RULE OUT A CHANCE SO
HAVE SLIGHT CHANCE POPS IN THE FORECAST FOR THE LATE AFTERNOON. WITH
850 TEMPS SLIGHTLY WARMER THAN TODAY, HAVE HIGHS A DEGREE OR SO
WARMER WITH GENERALLY MID 90S EXPECTED.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
SUNDAY EVENING WILL CONTINUE TO KEEP LOW PRECIPITATION CHANCES ALONG
THE WEAK FRONTAL BOUNDARY AS WELL AS THE INSTABILITY AXIS ACROSS THE
NORTHERN CWA. WILL LITTLE TO NO UPPER SUPPORT AND WEAK SURFACE
CONVERGENCE EXPECT ANY CONVECTION TO BE ON THE WANE AFTER SUNSET.
LOWS SUNDAY NIGHT WILL COOL INTO THE UPPER 60S TO LOWER 70S.
MONDAY FOR MUCH OF THE DAY LOOKS DRY WITH INCREASING CHANCES FROM
LATE AFTERNOON THROUGH EARLY MORNING HOURS ON TUESDAY ESPECIALLY
NEAR THE NEBRASKA BORDER NEAR THE VICINITY OF THE SURFACE FRONTAL
BOUNDARY IN SOUTHERN NEBRASKA. LOW LEVEL JET WILL INCREASE FROM THE
SOUTH AND SOUTHWEST MONDAY NIGHT BEFORE WEAKENING TUESDAY MORNING.
MODELS CONTINUE TO SHOW MID LEVEL SHORTWAVE MOVING THROUGH THE
PLAINS TUESDAY AND TUESDAY NIGHT.
WEDNESDAY THROUGH SATURDAY WILL BE MARKED BY COOLER TEMPERATURES
WITH PRECIPITATION CHANCES OFF AND ON AS WAVES MOVE THROUGH THE
NEARLY ZONAL FLOW ACROSS THE CENTRAL PLAINS. HIGH PRESSURE NOSES
INTO EASTERN KANSAS ON THURSDAY WITH A FRONTAL BOUNDARY SOUTH OF THE
FORECAST AREA. APPROACHING SHORTWAVE TROUGH AND INCREASING
ISENTROPIC LIFT OVER THE FRONT WILL KEEP A CHANCE FOR ELEVATED
THUNDERSTORMS THURSDAY NIGHT THEN CONTINUE ON FRIDAY WITH PASSAGE OF
THE UPPER TROUGH. COOLER HIGH PRESSURE BUILDS IN SATURDAY. COOLER
HIGH TEMPERATURES ARE EXPECTED FROM WEDNESDAY THROUGH SATURDAY IN
THE 80S.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 715 PM CDT SAT AUG 1 2015
VFR CONDITIONS ARE LIKELY THROUGH THE TAF WITH SOUTHWEST WINDS
INCREASING TO 10-15 KTS BY LATE MORNING ON SUNDAY.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...WOLTERS
LONG TERM...53
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS TOPEKA KS
558 PM CDT FRI JUL 31 2015
...UPDATE TO NEAR TERM CONVECTIVE FORECAST...
.UPDATE...
ISSUED AT 551 PM CDT FRI JUL 31 2015
MADE VERY LITTLE CHANGE TO THE ONGOING FORECAST. WHILE
THUNDERSTORMS ARE ONGOING IN NEBRASKA WITH A STRONG SOUTHERLY
COMPONENT TO THE MOTION, INSTABILITY DECREASES SHARPLY WITH
APPROACH TOWARD THE KANSAS BORDER. THE MAIN INSTABILITY AXIS SEEMS
TO RUN FROM SOUTHEAST NEBRASKA INTO NORTHWEST MISSOURI SO COULD
SEE SOME THUNDERSTORM ACTIVITY CLIP NORTHERN AND PARTICULARLY
NORTHEAST PARTS OF THE FORECAST AREA THIS EVENING. THE HRRR IS
VERY AGGRESSIVE WITH THUNDERSTORM COVERAGE (AS IT CAN BE AT TIMES
OF WEAK FORCING) AND BELIEVE IT IS LIKELY OVERDONE WITH THE
OVERALL COVERAGE AND PERSISTENCE OF THE STORM ACTIVITY INTO
KANSAS. AT THE SAME TIME...A STRONG COLD POOL HAS DEVELOPED FROM
NORTHERN STORMS AND WILL LIKELY WEAKEN AS IT MOVES INTO NORTHERN
KS...POSSIBLY STRONG ENOUGH TO KICK OFF ANOTHER STORM OR TWO.
BOTTOM LINE...STORM CHANCES THIS EVENING REMAIN LOW AND FOCUSED
OVER NORTHERN AND PERHAPS NORTHEAST KANSAS. IF ANYTHING DEVELOPS
INTO THE AREA THERE IS A VERY SMALL CHANCE FOR IT TO PRODUCE
MARGINALLY SEVERE HAIL OR LOCALLY DAMAGING WINDS.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
THUNDERSTORMS WERE DEVELOPING IN THE MOISTURE AND INSTABILITY AXIS
ALONG AN OLD OUTFLOW BOUNDARY IN NORTHERN AND EASTERN NEBRASKA THIS
AFTERNOON AT 20Z. FORECAST SHEAR THIS EVENING ACROSS NORTHEAST
KANSAS IS MARGINAL IN THE 25 TO 30 KT RANGE WITH MLCAPE FORECAST IN
THE 1000-2000 J/KG RANGE. CONVECTION IN NEBRASKA IF IT HOLDS
TOGETHER WOULD TRACK SOUTHEAST INTO NORTHEAST KANSAS THIS EVENING.
WITH LACK OF UPPER FORCING AND THE FOCUS FOR INSTABILITY AND
MOISTURE NORTH IN NEBRASKA WILL KEEP SMALL CHANCES OF PRECIPITATION
ACROSS THE NORTHERN COUNTIES FOR THE EVENING HOURS. LOWS SHOULD FALL
INTO THE UPPER 60S TO LOW 70S.
SATURDAY...MODELS DEVELOP SCATTERED SHOWERS AND THUNDERSTORMS DURING
THE LATE AFTERNOON ACROSS NEBRASKA AND THEN SOUTHEAST INTO SOUTHWEST
IOWA, NORTHWEST MISSOURI AND FAR NORTHEAST KANSAS AHEAD OF A WEAK
SHORTWAVE TROUGH. WILL KEEP A SMALL CHANCE OF THUNDERSTORMS NEAR THE
NEBRASKA BORDER IN THE LATE AFTERNOON HOURS. HIGHS A LITTLE WARMER
IN THE LOW TO MID 90S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 335 PM CDT FRI JUL 31 2015
SATURDAY NIGHT T0 MONDAY...
ANOTHER WAVE IS FCST TO SLIDE SE ACROSS THE REGION SAT NIGHT WHICH
SHOULD BRING ANOTHER ROUND OF STORMS TO PARTS OF NE/IA/MO AND
PERHAPS CLIPPING FAR NORTHEAST KS WITHIN THE LOW LEVEL WAA REGIME.
STRONGEST FORCING SHOULD REMAIN NE OF THE AREA SO WILL ONLY KEEP
LOWER CHC POPS FOR SAT NIGHT. BY SUNDAY SFC LOW PRESSURE WILL SLIDE
INTO WI WITH A COLD FRONT FCST TO SAG INTO THE STATE BY PEAK
HEATING. WILL LEAVE SLIGHT CHCS IN THE FCST FOR THE NORTHERN HALF
NEAR THE FRONT ON SUNDAY FOR RISK OF ISOLATED THUNDER IN THE
EVENING. BETTER CHANCES FOR STORMS WOULD APPEAR TO ARRIVE BY MONDAY
NIGHT AND BEYOND AS MID/UPPER WAVES MOVE ACROSS THE ROCKIES INTO THE
PLAINS AND INTERACT WITH A FRONTAL BOUNDARY IN THE VICINITY.
MONDAY NIGHT TO FRIDAY...
UPPER LEVEL NORTHWEST FLOW CONTINUES AS A SHORTWAVE MOVES OVER
NORTHERN KANSAS MONDAY NIGHT TO TUESDAY MORNING. THIS SHORTWAVE IS
PROGGED TO EXIT THE AREA BY TUESDAY AFTERNOON, BEFORE ANOTHER CHANCE
FOR PRECIPITATION IS SEEN TUESDAY TO WEDNESDAY MORNING ASSOCIATED
WITH ANOTHER PASSING SHORTWAVE. WITH NORTHWEST FLOW CONTINUING
THROUGH THE END OF THE PERIOD, SLIGHT CHANCES FOR STORMS REMAIN
UNTIL FRIDAY. HIGHS REMAIN IN THE LOW TO MID 90S THROUGH THURSDAY,
WITH A SLIGHT COOL DOWN FRIDAY DUE TO A SURFACE FRONTAL PASSAGE.
LOWS STAY MILD IN THE UPPER 60S/LOW 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1240 PM CDT FRI JUL 31 2015
VFR TO CONTINUE THROUGH THE PERIOD. SHOULD BE MIXED ENOUGH TO
PREVENT VISIBILITY RESTRICTIONS LATE TONIGHT. CONVECTION IS
EXPECTED TO REMAIN TO THE NORTH AND EAST OF THE TERMINALS.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...53
LONG TERM...HELLER/OMITT
AVIATION...53
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
339 PM CDT FRI JUL 31 2015
...UPDATED LONG TERM SECTION...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 338 PM CDT FRI JUL 31 2015
THE BEST CHANCE FOR THE NEXT ORGANIZED PRECIPITATION EVENT WILL BE
MONDAY NIGHT INTO TUESDAY. THE GLOBAL SPECTRAL MODELS CONTINUE TO
SHOW AN INTERACTION BETWEEN MONSOON PERTURBATIONS MOVING NORTHWARD
THROUGH THE DESERT SOUTHWEST...AND AN INCOMING SUBTROPICAL PACIFIC
JET MOVING INTO THE INTERMOUNTAIN WEST REGION. THIS WILL ACT TO
SHIFT THE MONSOON CIRCULATION NORTHEASTWARD SOME...ENHANCING THE
PRECIPITATION POTENTIAL FOR SOUTHWEST KANSAS. IT VERY WELL COULD BE
JUST ONE BIG MCS WE SEE OUT OF THIS EVENT, IN WHICH CASE IF THE
ECMWF HAS A HANDLE ON THINGS, WOULD BE MONDAY NIGHT. THIS IS WHEN
THE HIGHEST POPS ARE IN THE GRIDS FOR THE ENTIRE REGION. ONCE THAT
WAVE EXITS THE CENTRAL PLAINS...THE SUMMER SUBTROPICAL RIDGE WILL
BUILD BACK IN, HOWEVER DEEP TROPOSPHERIC MONSOON MOISTURE WILL BE
FAIRLY SCANT AND IT WILL NEED TO BE RECHARGED AGAIN BY WAY OF LATE
DAY HIGH TERRAIN THUNDERSTORMS. THE LATEST ECMWF FAVORS RIDGE-
BUILDING INTO THE NORTHERN PLAINS WHICH WOULD RESULT IN A WARMING OF
THE LOWER TROPOSPHERE AND SURFACE TEMPERATURES REACHING OR EXCEEDING
THE UPPER 90S BY MID TO LATE NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
FAIRLY QUIET AVIATION WEATHER IS EXPECTED THROUGH TONIGHT AND EARLY
SATURDAY WITH A WEAK PRESSURE GRADIENT RESULTING IN THE CONTINUATION
OF WINDS BELOW 12 KNOTS FOR THE MOST PART. CONVECTIVE ACTIVITY IS
EXPECTED TO REMAIN SOUTH OF THE GCK AND DDC TERMINALS, SO WE WILL
NOT BE FORECASTING ANY THUNDERSTORMS AT THIS TIME. VFR CONDITIONS
ARE EXPECTED TO PREVAIL, HOWEVER THERE COULD BE A BRIEF PERIOD OF
MVFR CEILINGS IN THE EARLY MORNING HOURS AT GCK AND DDC AS
THUNDERSTORM ACTIVITY TO THE SOUTH COULD HAVE SOME IMPACT SIMILAR TO
WHAT WE SAW EARLIER THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 68 87 67 93 / 10 10 10 10
GCK 67 87 67 92 / 10 10 10 10
EHA 66 85 67 92 / 20 40 20 10
LBL 68 83 68 92 / 20 30 20 10
HYS 67 93 67 95 / 10 10 10 10
P28 71 90 70 94 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
200 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 200 PM MDT FRI JUL 31 2015
FOR THE EXTENDED PERIOD...THE LATTER PORTION OF THE WEEKEND RIGHT
THROUGH MUCH OF NEXT WEEK...THE ENTIRE TRI STATE REGION WILL SEE
ABOVE NORMAL TEMPERATURES BROUGHT ABOUT BY A STRONG AMPLIFIED
500/700 MB RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...THAT
SHIFTS EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY. LATEST
MODEL RUNS STILL SHOW 850 MB TEMPS RANGING FROM +29C TO ALMOST
+35C...UNDER WNW UPPER FLOW. THIS IS GOING TO GIVE THE AREA DAYTIME
HIGHS WELL INTO THE 90S...WARMEST ON WEDNESDAY WHEN UPPER RIDGE AXIS
SETTLES OVER THE REGION AND COULD GIVE MID TO UPPER 90S TO THE AREA.
COOLER AIR COULD ARRIVE DURING THE DAY FRIDAY WITH SURFACE RIDGE
BUILDING SOUTH THRU THE PLAINS AFTER FRONTAL PASSAGE LATE THURSDAY
NIGHT.
DESPITE STRONG RIDGING OVER THE REGION OVER THE NEXT WEEK...SEVERAL
SHORTWAVES ARE EXPECTED TO TRAVERSE OVER THE NORTHERN HALF OF THE
RIDGE...BRINGING THE CHANCE FOR SHOWERS/THUNDERSTORMS. THIS ACTIVITY
THOUGH WILL SPARE THE FORECAST AREA FOR THIS UPCOMING WEEKEND...ONLY
TO BEGIN WITH A STRONG TROUGH LATE MONDAY INTO TUESDAY AND THEN
SUBSEQUENT SYSTEMS. BEST CHANCES FOR PRECIP THOUGH AS WEEK
PROGRESSES WILL BEGIN TO SHIFT MORE EASTWARD OVER THE CWA...DUE TO
MOVEMENT OF UPPER RIDGE WHICH WILL AFFECT PLACEMENT OF EACH LATTER
SHORTWAVE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JN
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
141 PM MDT FRI JUL 31 2015
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 141 PM MDT FRI JUL 31 2015
PERSISTENT UPPER LEVEL RIDGE CONTINUES TO DOMINATE PATTERN ACROSS
WESTERN US THROUGH THE SOUTHERN PLAINS...WITH NW FLOW ACROSS THE
NORTHERN PLAINS. WV IMAGERY SHOWS MONSOONAL MOISTURE PLUME EXTENDING
FROM THE BAJA PENINSULA ACROSS THE FOUR CORNER AND INTO THE HIGH
PLAINS WITH SEVERAL WEAK SHORTWAVE TROUGHS ROTATING AROUND RIDGE
INTO THE SOUTHERN PLAINS AND THROUGH THE NW FLOW ALONG THE MISSOURI
RIVER VALLEY. AT THE SURFACE...MEAN SURFACE TROUGH EXTENDS ACROSS
NORTHERN COLORADO INTO CENTRAL NEBRASKA...WITH WEAK FLOW AND A
SECONDARY WEAK TROUGH AXIS/SURFACE CONVERGENT ZONE ALONG THE KS CO
BORDER EXTENDING SOUTH INTO SOUTH CENTRAL KS.
MODELS CONTINUE TO UNDERESTIMATE TDS WITH 60-70F TD VALUES REPORTED
MOST OF THE DAY...FINALLY BEGINNING TO FALL IN OUR NW. RESULT IS
MUCH HIGHER CAPE VALUES THAN PREVIOUSLY ADVERTISED WITH RAP ANALYSIS
SHOWS A SHARP GRADIENT OF SB CAPE FROM 250 J/KG IN NORTHEAST
COLORADO TO 3000 J/KG OVER OUR SOUTHERN CWA. CONSIDERING THE MOIST
BL LAYER AND FAVORABLE CAPE PROFILES OVER MOST OF THE AREA IT WON`T
TAKE MUCH FOR THUNDERSTORMS TO DEVELOP. WITH ONLY WEAK HEIGHT FALLS
THIS AFTERNOON/TONIGHT AND MODELS SHOWING ALMOST NO ACTIVITY
INITIATING OVER OUR CA (DESPITE LOW CINH)...I AM FAVORING ISOLATED
THUNDERSTORM MENTION FOR NOW. AS WITH LAST NIGHT...VERY LITTLE STORM
MOTION (0-6KM 0-5KT ACROSS MUCH OF THE AREA) WILL RESULT IN
POTENTIAL FOR FLASH FLOODING. IF CELL MERGERS OCCUR AND ARE ABLE TO
DEVELOP A COLD POOL OR OUTFLOW WE COULD SEE BETTER COVERAGE. LOW
CONFIDENCE AT THIS POINT.
SATURDAY...PATTERN WILL BE VERY SIMILAR AS TODAY WITH SEASONAL HIGHS
(UPPER 80S-MID 90S). GUIDANCE ACTUALLY INDICATING SUBSIDENCE WILL BE
IN PLACE...SO WHILE HIGH CAPE VALUES/DECENT MOISTURE PROFILES WILL
LIKELY SET UP OVER THE CWA ONCE AGAIN CONFIDENCE IN ANY INITIATION
IS EVEN LOWER THAN TODAY. I DECIDED TO KEEP THUNDERSTORM MENTION
OUT FOR NOW.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1228 PM CDT FRI JUL 31 2015
...UPDATED SHORT TERM AND AVIATION SECTIONS...
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
THE SUMMER SUBTROPICAL RIDGE WAS CENTERED OVER ITS CLIMATOLOGICAL
POSITION FROM THE SOUTHERN ROCKIES INTO TEXAS TODAY. IN THE UPPER
TROPOSPHERE, WEST NORTHWEST FLOW EXTENDED FROM THE NORTHERN ROCKIES
THROUGH THE UPPER MISSISSIPPI VALLEY. WESTERN KANSAS WAS ON THE
SOUTH EDGE OF THE WESTERLIES AT 250MB. THE MESOSCALE CONVECTIVE
SYSTEM (MCS) THAT AFFECTED EXTREME SOUTHWEST KANSAS OVERNIGHT AND
THIS MORNING WAS DECREASING IN AREAL EXTENT AND MOVING VERY SLOWLY
TO THE EAST-SOUTHEAST...FOLLOWING ROUGHLY THE 3-8KM AGL MEAN FLOW
VECTOR (JUST NORTH OF THE CENTER OF THE MEAN ANTICYCLONE IN THIS
LAYER OVER WEST TEXAS). A COUPLE OF MESOSCALE CONVECTIVE VORTICITY
MAXIMAS COULD BE IDENTIFIED THROUGH VISIBLE SATELLITE AND EVEN THE
HOURLY RAP ANALYSIS FROM NEAR TUCUMCARI NEW MEXICO TO NEAR
SPRINGFIELD COLORADO. IT WOULD APPEAR AS OF THESE MESOSCALE FEATURES
WERE ACTUALLY HELPING TO MAINTAIN THE SMALL MCS THROUGH THE EARLY
AFTERNOON HOURS AS THE LEADING EDGE OF IT WAS MOVING INTO THE FAR
EASTERN OK-TX PANHANDLES. THE VERY NORTHERN EXTENT OF THIS MCS
EXTENDED INTO MORTON AND SEWARD COUNTIES, WHICH WAS HAVING AN IMPACT
ON SURFACE TEMPERATURES (COOLER THAN FORECAST IN THIS AREA). WE HAVE
ADJUSTED THE DAYTIME TEMPERATURES DOWNWARD ACROSS FAR SOUTHWEST
KANSAS AS A RESULT. ELSEWHERE...ESPECIALLY ACROSS WEST CENTRAL AND
CENTRAL KANSAS NORTH OF HIGHWAY 96, TEMPERATURES SHOULD TOP OUT IN
THE LOWER TO MID 90S.
AS WE GO IN TO TONIGHT...ANOTHER SMALL MCS SHOULD EVOLVE THROUGH THE
LATE NIGHT HOURS FROM CONVECTION ACROSS THE HIGHER TERRAIN OF THE
RATON MESA REGION. THIS CONVECTION SHOULD FOLLOW THE SAME GENERAL
TRACK AS THIS MORNINGS MCS, SO WE WILL KEEP THE BEST POPS ACROSS FAR
SOUTHWEST KANSAS AGAIN IN THE 40-50 PERCENT RANGE. THE BULK OF LATE
TONIGHT/TOMORROWS MCS SHOULD REMAIN ACROSS THE PANHANDLES REGION. IT
SHOULD BE CLOSE TO A RINSE AND REPEAT TYPE OF DEAL TOMORROW WITH A
SLOWLY DECAYING MCS SOMEWHERE JUST SOUTH OF OUR FORECAST AREA (OR
PERHAPS CLIPPING MORTON-SEWARD-MEADE) WITH WARMEST TEMPERATURES UP
NORTH ALONG I-70 (MID 90S) AND COOLEST TEMPERATURES ALONG THE OK
BORDER (LOWER-MID 80S, IF EVEN THAT WARM).
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 200 AM CDT FRI JUL 31 2015
SATURDAY WILL BE SOMEWHAT INTERESTING. SYNOPTICALLY THERE ISN`T MUCH
FOCUS FOR THUNDERSTORM DEVELOPMENT. ARW AND NMM ARE PRECIPITATION FREE.
THE ECMWF, INTERESTINGLY ENOUGH, IS WETTER AS IT HAS STRONGER LOW LEVEL
LIFT. AT THIS POINT, WILL KEEP THE FORECAST DRY AND LET FUTURE SHIFTS
ADJUST AS NEEDED. IF THERE IS CONVECTION, THEN HIGH TEMPERATURES COULD
BE TRICKY AS SOME COOLER AREAS WILL RESULT. SUNDAY SHOULD BE FAIRLY
DRY AS SHORTWAVE RIDGING STARTS TO NOSE IN FROM THE WEST. HIGHS WILL
MODERATE A FEW DEGREES AND WILL BE AROUND 90F. FOR THE REST, STUCK WITH
SUPERBLEND POPS AND TEMPS AS THE GRIDS LOOK REASONABLE. THERE WILL BE
A CHANCE FOR STORMS AGAIN AS A FEW SYNOPTIC WAVES MOVE ACROSS THE GREAT
PLAINS NEXT WEEK. HIGHS WILL STILL BE ON THE WARM SIDE WITH MILD LOWS...
SUMMER CONTINUES.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1226 PM CDT FRI JUL 31 2015
FAIRLY QUIET AVIATION WEATHER IS EXPECTED THROUGH TONIGHT AND EARLY
SATURDAY WITH A WEAK PRESSURE GRADIENT RESULTING IN THE CONTINUATION
OF WINDS BELOW 12 KNOTS FOR THE MOST PART. CONVECTIVE ACTIVITY IS
EXPECTED TO REMAIN SOUTH OF THE GCK AND DDC TERMINALS, SO WE WILL
NOT BE FORECASTING ANY THUNDERSTORMS AT THIS TIME. VFR CONDITIONS
ARE EXPECTED TO PREVAIL, HOWEVER THERE COULD BE A BRIEF PERIOD OF
MVFR CEILINGS IN THE EARLY MORNING HOURS AT GCK AND DDC AS
THUNDERSTORM ACTIVITY TO THE SOUTH COULD HAVE SOME IMPACT SIMILAR TO
WHAT WE SAW EARLIER THIS MORNING.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 88 68 85 66 / 10 10 10 10
GCK 86 67 86 65 / 10 10 10 10
EHA 78 66 86 64 / 80 40 10 10
LBL 81 68 85 65 / 20 20 10 10
HYS 94 67 89 67 / 10 10 10 10
P28 85 71 84 68 / 10 10 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM...SUGDEN
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1119 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1119 AM MDT FRI JUL 31 2015
VFR CONDITIONS CURRENTLY FORECAST THROUGH THE TAF PERIOD AT BOTH
KGLD AND KMCK. LOW CONFIDENCE OVERALL IN AVIATION FORECAST AS A
RESULT OF POOR MODEL PERFORMANCE REGARDING LOW LEVEL MOISTURE
OVER BOTH TERMINALS. I COULD SEE PATCHY FOG DEVELOPING AGAIN BY
SUNRISE SATURDAY IF HIGHER DEWPOINTS CONTINUE TO LINGER...HOWEVER
AT THIS POINT THERE IS NO MODEL SUPPORT SO I LEFT MENTION OUT.
OTHER AVIATION CONCERN WILL BE POTENTIAL FOR THUNDERSTORMS.
CURRENTLY ACTIVITY IS EXPECTED TO BE ISOLATED WITH BETTER CHANCES
IN EASTERN COLORADO...SO WILL LEAVE OUT OF TAFS DURING THIS
UPDATE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
518 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 516 AM MDT FRI JUL 31 2015
PATCHY DENSE FOG WILL IMPACT KGLD THROUGH ABOUT 14Z BEFORE
CLEARING. VISIBILITIES HAVE BEEN HIGHLY VARIABLE BUT AS LOW AS
1/4SM AT TIMES. OTHERWISE...VFR EXPECTED AT BOTH KGLD AND KMCK
THROUGH THE REMAINDER OF THE TAF PERIOD WITH RIDGING ALOFT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...024
AREA FORECAST DISCUSSION
NWS GOODLAND KS
235 AM MDT FRI JUL 31 2015
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
UPPER RIDGE OVER THE GREAT BASIN WILL GRADUALLY BUILD OVER THE
CENTRAL ROCKIES AND BE THE DOMINANT FEATURE OF THE SHORT TERM
PERIOD. AS A RESULT...PRECIPITATION CHANCES WILL BE RATHER LOW AND
TEMPERATURES WILL BE WARMING. THAT BEING SAID...MAY SEE AN ISOLATED
STORM OR TWO THIS AFTERNOON IN NORTHEAST COLORADO AS HINTED AT BY
THE HRRR NEAR A WEAK SURFACE CONVERGENCE LINE. ENVIRONMENT WILL
BE SIMILAR TO YESTERDAY SO CANT TOTALLY RULE OUT A SEVERE STORM
CAPABLE OF PRODUCING STRONG WINDS...BUT THINK COVERAGE WILL BE
VERY LIMITED DUE TO LACK OF UPPER SUPPORT. SOME OF THE HIRES NAM
MEMBERS PAINT A SIMILAR SCENARIO SATURDAY AFTERNOON IN NORTHEAST
COLORADO SO CARRIED SOME LOW POPS. ONCE AGAIN SEVERE PARAMETERS
ARE FAIRLY DECENT SHOULD SOMETHING DEVELOP. PERHAPS THE NEXT BEST
CHANCE FOR THUNDERSTORMS WILL BE SUNDAY AFTERNOON AND EVENING WITH
SOMEWHAT BETTER LOOKING TROUGH COMING OUT OF COLORADO AND TOPPING
THE RIDGE AXIS IN THE CENTRAL PLAINS. HOWEVER NOT ENOUGH
CONFIDENCE AT THIS POINT WITH THE STRONG RIDGE IN PLACE THAT IT
WILL ACTUALLY PLAY OUT THAT WAY SO WILL ONLY CARRY SILENT 10 POPS
OR LESS.
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 209 AM MDT FRI JUL 31 2015
THE UPPER LEVEL SETUP FOR THE EXTENDED PERIOD CONTINUES TO BE
RIDGING OVER THE WESTERN CONUS ALONG WITH A TROUGH TO THE EAST. THE
RIDGE IS EXPECTED TO SHIFT EASTWARD WITH ITS AXIS LIKELY OVER THE
AREA BY THURSDAY.
SHOWERS AND THUNDERSTORMS ARE POSSIBLE AT THE START OF THE PERIOD AS
A SHORTWAVE TROUGH PASSES THROUGH THE UPPER LEVEL FLOW AND OVER THE
AREA MONDAY INTO TUESDAY. THE UPPER LEVEL RIDGE OVER THE WESTERN
CONUS REGAINS ITS SHAPE LATE TUESDAY AND PROGRESSES EASTWARD ON
WEDNESDAY AND THURSDAY TOWARDS THE PLAINS AS A CLOSED LOW APPROACHES
THE PACIFIC NORTHWEST. WEAKER DISTURBANCES LOOK TO MOVE ALONG THE
RIDGE WEDNESDAY AND THURSDAY...GENERATING PRECIP CHANCES ONCE AGAIN.
WARM TEMPERATURES WILL CONTINUE FOR THE TRI STATE REGION WITH HIGHS
IN THE UPPER 80S TO MID 90S FOR THE DURATION OF THE LONG TERM
PERIOD. LOWS LOOK TO BE IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM MDT THU JUL 30 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS THROUGH THE
DURATION OF THE TAF PERIOD. AN UPPER LEVEL HIGH PRESSURE SYSTEM
WILL BRING DRY CONDITIONS WITH LIMITED CLOUD COVER...AS WELL AS
LIGHT SOUTHERLY WINDS TO BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...024
LONG TERM...JBH
AVIATION...MK
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1125 PM MDT THU JUL 30 2015
.UPDATE...
ISSUED AT 743 PM MDT THU JUL 30 2015
THUNDERSTORMS IN EASTERN COLORADO ARE FOLLOWING A SOUTHWARD
TRAJECTORY WITH THE CLOUD COVER MOVING MORE TO THE EAST/SOUTHEAST.
MODELS INDICATE STORMS SHOULD HAVE ENDED...BUT STORMS CONTINUE TO
MOVE ALONG 500 MB SHORTWAVE TROUGH JUST EAST OF THE 12 C 700 MB
ISOTHERM. AT THE CURRENT SPEED...STRONGER STORMS SHOULD MOVE OUT
OF THE FORECAST AREA BY MIDNIGHT MDT. SLIGHT CHANCES FOR SOME
PRECIPITATION WILL LINGER A LITTLE AFTER MIDNIGHT MDT AS THE SMALL
SHORTWAVE MOVES THROUGH THE HIGH PLAINS.
UPDATE ISSUED AT 430 PM MDT THU JUL 30 2015
ISSUED A QUICK UPDATE TO ADJUST COVERAGE AND THUNDERSTORM TIMING
MOVING INTO THE EASTERN COLORADO COUNTIES. THE WRF MODELS SEEM TO
BE HAVING THE BEST HANDLE ON THE CURRENT CONVECTIVE MODE...HOWEVER
PRECIPITATION IN THE MODELS ARE 3-6 HOURS LATE IN DEVELOPMENT.
STORMS MAY DISSIPATE EARLIER THAN ANTICIPATED DUE TO THE EARLIER
DEVELOPMENT...BUT WILL LEAVE IN PRECIPITATION CHANCES AFTER
MIDNIGHT MDT FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MDT THU JUL 30 2015
EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD RIDGE
ACROSS THE SOUTHERN PLAINS EXTENDING ACROSS THE CENTRAL ROCKIES AND
ACROSS THE GREAT BASIN. NW FLOW IS IN PLACE ACROSS THE NORTHERN
PLAINS AND GREAT LAKES REGIONS. A WEAK RIPPLE IN THE HEIGHT FIELD IS
DEPICTED OVER NW KANSAS WITH A STRONGER PV HEIGHT ANOMALY OVER NEW
MEXICO AND STRONGER SIGNAL IN WV IMAGERY. AT THE SURFACE LOW
PRESSURE HAS DEVELOPED ACROSS EASTERN COLORADO WITH A STATIONARY
FRONT EXTENDING FROM THE SW TO NE TOWARDS THE NEBRASKA PANHANDLE.
HIGH PRESSURE IS IN PLACE ACROSS THE CENTRAL PLAINS AND CENTRAL
MISSISSIPPI RIVER VALLEY.
THIS AFTERNOON-TONIGHT...CAPE VALUES IN THE 1500-2500 J/KG RANGE ARE
CURRENTLY IN PLACE WITH HIGHER TD VALUES (UPPER 50S TO MID 60S).
RAP/HRRR INDICATE CAP ALREADY WEAKENED...AND THUNDERSTORM ACTIVITY
MAY BEGIN TO DEVELOP ALONG WEAK CONVERGENCE ZONE NEAR SURFACE
TROUGH/STATIONARY FRONT IN EASTERN COLORADO. GUIDANCE GENERALLY
SHOWS BETTER PRECIP SIGNAL IN THIS AREA. VERY WEAK LIFT IS IN PLACE
AND AT THIS POINT COVERAGE LOOKS TO BE ISOLATED TO WIDELY SCATTERED
THROUGH TONIGHT. THERE WILL BE SOME WAA THROUGH THE NIGHT WHICH
COULD SUPPORT CONTINUED DEVELOPMENT...HOWEVER WITH BEST FORCING
OUTSIDE OUR CWA...NOT A LOT OF CONFIDENCE. I LIMITED POPS TO 15-24
RANGE (SLIGHT CHANCE). WITH WEAK SHEER PROFILES IN PLACE...LIMITED
FORCING...AND MID LEVEL LAPSE RATES MAINLY LESS THAN 7 C/KM
THUNDERSTORM ACTIVITY IS NOT EXPECTED TO BECOME ORGANIZED.
FRIDAY...SURFACE TROUGH SHIFTS EAST TO BE CENTERED ROUGHLY OVER OUR
CWA AND MAY ACT AS A FOCUS/INITIATION POINT FOR AFTERNOON
THUNDERSTORM ACTIVITY. BEST UPPER LEVEL SUPPORT IS IN THE MORNING
OUTSIDE OUR CWA...WITH POSSIBLY LESS UPPER LEVEL SUPPORT FRIDAY
AFTERNOON THAN TODAY. THERE SHOULD STILL BE ENOUGH
INSTABILITY/MOISTURE IN PLACE TO SUPPORT SOME THUNDERSTORM ACTIVITY
ALONG TROUGH AXIS...HOWEVER COVERAGE STILL APPEARS TO BE ISOLATED IN
NATURE. EFFECTIVE SHEER PROFILES AROUND 30KT AND CAPE VALUES 1500-
3000 J/KG COULD SUPPORT A FEW STRONGER STORMS HOWEVER LIKE TODAY
SEVERE THREAT APPEARS TO BE LOW. HIGH TEMPERATURES WILL BE SLIGHTLY
WARMER AND STILL SEASONAL WITH VALUES RANGING FROM THE UPPER 80S TO
LOWER 90S. A FEW MID 90 TEMPERATURES WILL BE POSSIBLE AT KMCK/KHLC.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 150 PM MDT THU JUL 30 2015
ABOVE NORMAL TEMPERATURES ARE ON TAP FOR THE ENTIRE TRI STATE
REGION...AS MAIN WEATHER FOCUS FOR THE EXTENDED PERIOD WILL CONCERN
AMPLIFIED H5/H7 RIDGE OVER THE WESTERN PORTION OF THE COUNTRY...
SHIFTING EASTWARD INTO THE PLAINS REGION BY NEXT WEDNESDAY/THURSDAY.
EXPECTING BROAD WNW DOWNSLOPE FLOW AT 700/500 MB WITH RIDGE TO OUR
WEST...WITH RIDGE AXIS OVER THE PLAINS BY MIDWEEK NEXT WEEK. 850 MB
TEMPS DO RANGE FROM +28C UP TO +33C DURING THIS TIME...WITH WARMEST
SET TO OCCUR WED/THURS...COINCIDING WITH RIDGE AXIS SETTING UP OVER
THE AREA. WITH THESE CONDITIONS...DAYTIME HIGH TEMPERATURES WILL
RANGE IN THE LOWER TO MID 90S...AND OVERNIGHT LOWS IN THE LOW TO MID
60S.
THE AREA WILL ALSO SEE THE CHANCES FOR SHOWERS AND THUNDERSTORMS
DESPITE THE INCREASE TEMPS. SEVERAL SHORTWAVES MOVING DOWN ALONG THE
EAST SIDE OF THE MID-LEVEL RIDGE FRIDAY/FRIDAY NIGHT...NEXT MONDAY
INTO TUESDAY...AND AGAIN LATE WEDNESDAY INTO THURSDAY WHEN SURFACE
FRONT IS FOLLOWED BY TRAILING SHORTWAVE. CURRENT GFS A BIT MORE IN-
LINE WITH LATEST ECMWF...MAKING CONFIDENCE A BIT STRONGER IN KEEPING
CHANCE POPS FOR LATTER PORTION OF THE FORECAST. THE PUSH OF THE
UPPER RIDGE EASTWARD INTO THE PLAINS DOES PUT A BIT MORE EMPHASIS
FOR HIGHER POP CHANCES OVER EASTERN ZONES ON WEDNESDAY INTO
THURSDAY. AS WITH EXPECTED RAINFALL POTENTIAL...THE CLOUD COVER WITH
THESE EVENTS COULD IMPACT DAYTIME HIGHS/OVERNIGHT LOWS...ESPECIALLY
IN EASTERN ZONES AS WEEK PROGRESSES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1122 PM MDT THU JUL 30 2015
VFR CONDITIONS ARE EXPECTED FOR BOTH TERMINALS THROUGH THE
DURATION OF THE TAF PERIOD. AN UPPER LEVEL HIGH PRESSURE SYSTEM
WILL BRING DRY CONDITIONS WITH LIMITED CLOUD COVER...AS WELL AS
LIGHT SOUTHERLY WINDS TO BOTH KGLD AND KMCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...MK
SHORT TERM...DR
LONG TERM...JN
AVIATION...MK
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1216 PM CDT FRI JUL 31 2015
.UPDATE...
UPDATED FORECAST AND GRIDS TO LOWER RAIN CHANCES ACROSS SOUTHERN
HALF OF AREA TO 20 PERCENT...AND HRRR WOULD INDICATE THAT MAY BE A
LITTLE HIGH. ADJUSTED HOURLY TEMPERATURES AND DEW POINTS TO FIT
CURRENT TRENDS.
&&
.PREV DISCUSSION... /ISSUED 415 AM CDT FRI JUL 31 2015/
SHORT TERM...
THE HEAT WILL BE ON FOR A SHORT TIME TODAY. BUT A COLD FRONT JUST
TO THE NORTH OF THE AREA WILL SLOWLY MOVE THROUGH TODAY. DEW PTS
WILL BEGIN TO LOWER IN MCB BY SUNRISE AND SHOULD REACH ABOUT 63
DEGREES BY AFTERNOON. DP TEMPS WILL LOWER IN SLIDELL AROUND NOON
AND TO THE SOUTH SHORE SHORTLY AFTER. THIS CONTRAST TO THE DP
TEMPS THAT WE HAVE BEEN UNDER LATELY WILL BE FELT. THIS WILL ALSO
DO TWO THINGS. ONE WILL BE TO KEEP TEMPS NEAR WHAT THEY HAVE BEEN
OR EVEN SLIGHTLY HIGHER. THE SECOND THING WILL BE TO KEEP THE HEAT
INDEX VALUES DOWN. TIMING OF SH/TS HAVE BEEN OFF THE LAST FEW DAYS
AND THAT ALWAYS HAS A MAJOR IMPACT ON TEMPS AND THEREFORE HEAT
INDEX VALUES. BUT TODAY SHOULD NOT BE A TIMING ISSUE AS DRY AIR
WILL BE THE CAUSE OF LOWER HEAT INDICES. THE FRONT WILL MOVE BACK
TO THE NORTH BY SAT NIGHT BRINGING BACK THE MOISTURE AND HIGHER
HEAT INDEX VALUES. THE FRONT SHOULD ALSO KEEP ALL SH/TS ACTIVITY
ALONG AND SOUTH OF IT SO POP GRADIENTS HAVE BEEN SET ACCORDINGLY.
LONG TERM...
SH/TS WILL ONCE AGAIN BE BACK TO THE AREA ONCE THE COLD FRONT
LIFTS NORTH OVER THE WEEKEND. AFTER THE WEEKEND...MOST SH/TS WILL
BE ACTIVATED BY C-BRZ AND OUTFLOW BOUNDARIES.
AVIATION...
VFR CONDITIONS ARE EXPECTED WITH THE MAIN EXCEPTION AT KHUM WHERE
SOME TEMPO MVFR WILL CONTINUE THIS MORNING DUE TO LIGHT FOG.
MAINTAIN VCTS THIS AFTERNOON FOR THE AIRPORTS CLOSER TO THE COAST
WHERE THERE IS A BETTER CHANCE OF CONVECTION. 18
MARINE...
A COLD FRONT IS EXPECTED TO PUSH SOUTH ACROSS THE TIDAL
AND EXTREME NEAR SHORE WATERS TODAY AND STALL. A SLIGHT DECREASE IN
THICKNESS 1000-700MB SHOW A 10 TO 15 METER DROP TODAY. NORTH WINDS
WILL KICK UP TO 10 TO 15 KNOTS ACROSS NEAR SHORE WATERS THIS MORNING
AND AGAIN SATURDAY MORNING. THE STALLED COLD FRONT OVER THE COASTAL
WATERS WILL BEGIN TO LOSE ITS IDENTITY OVER THE WEEKEND. HIGH
PRESSURE WILL BUILD OVER THE EAST GULF AND YIELD A WESTERLY FLOW
OVER THE NORTH CENTRAL GULF EARLY NEXT WEEK. 18
DECISION SUPPORT...
DSS CODE....BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...RIVER FLOOD WARNINGS ON MISSISSIPPI RIVER FROM RED
RIVER LANDING TO DONALDSONVILLE.
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED WATCH/WARNING/ADVISORY
ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE RISK SVR AND/OR DIRECT
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 95 68 94 69 / 10 0 0 0
BTR 96 70 95 70 / 10 10 0 0
ASD 92 72 94 70 / 10 10 10 10
MSY 93 78 93 79 / 20 10 10 20
GPT 93 74 92 71 / 10 20 20 20
PQL 94 75 91 70 / 20 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
748 PM EDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 323 PM EDT SAT AUG 1 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN CLOSED UPR LO OVER HUDSON BAY AND RDG ACROSS THE
WRN CONUS. THE 12Z INL/GRB RAOBS SHOW A RELATIVELY DRY...CAPPED
ENVIRONMENT...SO THE DIURNAL CU THAT POPPED UP HAVE BEEN FAIRLY
SHALLOW WITH LARGE SCALE DEEP LYR QVECTOR DVGC/SUBSIDENCE
DOMINATING. THE ONLY EXCEPTION IS OVER THE SE CWA E OF ESCANABA...
WHERE RADAR INDICATES A FEW SHOWERS HAVE POPPED UP IN AN AREA CLOSER
TO SOME DEEPER MSTR/LESS CAPPED ENVIRONMENT SHOWN ON THE 12Z APX
RAOB AND WHERE LLVL CNVGC HAS BEEN ENHANCED BY LK BREEZE CNVGC.
LOOKING UPSTREAM...A SHRTWV IS DROPPING SEWD THRU MANITOBA. THERE IS
A BAND OF CLDS AND A FEW SHOWERS ASSOCIATED WITH AXIS OF HIER H7 RH
IN AREA OF DPVA/H7-5 QVECTOR CNVGC MOVING INTO NW ONTARIO AHEAD OF
THIS FEATURE. FARTHER AWAY...ANOTHER SHRTWV TOPPING WRN RDG IS
MOVING ESEWD THRU SASKATCHEWAN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON SHOWER/TS CHANCES
ASSOCIATED MAINLY WITH THE TWO SHRTWVS NOTED ABOVE.
TNGT...FIRST SHRTWV OVER MANITOBA IS FCST TO SLIDE SEWD THRU NW
ONTARIO...WITH SHARPER DPVA/DEEP LYR QVECTOR CNVGC REMAINING TO THE
N. ALTHOUGH THE LLVL FLOW IS FCST TO BACK TOWARD THE WSW TO THE S OF
THE TRACK OF THIS DISTURBANCE...GUIDANCE INDICATES THE MOST
IMPRESSIVE MSTR CNVGC WL REMAIN TO THE S IN WI...JUST BRUSHING THE
BORDER. WITH THE DISCONNECT BTWN THIS MOISTENING TO THE S AND THE
MORE IMPRESSIVE DYNAMIC SUPPORT REMAINING TO THE N...SUSPECT PCPN
OVER MUCH OF UPR MI WL BE RATHER LIMITED BTWN AXES OF HIER POPS TO
THE N AND ALONG THE SRN CWA/WI. INCRSG PWAT AND WSW FLOW WL TEND TO
LIMIT THE DIURNAL TEMP DROP.
SUN...DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF SHRTWV NOW MOVING
THRU SASKATCHEWAN IS FCST TO ARRIVE OVER SLOW MOVING...WEAKENING
COLD FNT THAT WL BE DROPPING SLOWLY SE ACRS THE CWA ATTENDANT TO
FIRST DISTURBANCE EXITING INTO QUEBEC. SOME OF THE MODELS...
ESPECIALLY THE 12Z GFS...ALSO HINT AT THE POTENTIAL FOR SOME
ENHANCED UPR DVGC IN RRQ OF EXITING H3 JET MAX SUPPORTING THE FIRST
DISTURBANCE AND EXIT REGION OF INCOMING JET STREAK ASSOCIATED WITH
2ND SHRTWV. SINCE THIS FORCING WL BE ARRIVING DURING PERIOD OF
DAYTIME HEATING...SUSPECT SHOWERS/TS WL BECOME MORE NUMEROUS. SO
TENDED TO BUMP POPS UP INTO THE LIKELY RANGE OVER MUCH OF THE CWA.
WITH INCRSG H85-5 RH...THERE ARE CONCERNS ABOUT HOW MORE CLDS WL
IMPACT SFC DESTABILIZATION. THE 12Z NAM SHOWS MUCAPE AS HI AS 2500-
3000 J/KG OVER THE SCENTRAL UNDER AREA OF STEEP H7-5 LAPSE RATES
APRCHG 8C/KM PER THE THE 12Z GFS. ALTHOUGH MOST OF THE GUIDANCE
SUGGESTS THE BULK OF THE PCPN WL FALL ON THE COOL SIDE OF THE FNT
AND THERE WL BE A GOOD DEAL OF CLD COVER THAT SUG THE NAM FCST
MUCAPE IS TOO HI...TS THAT FORM ALONG AND AHEAD OF THE FNT
ESPECIALLY OVER THE SCENTRAL COULD TURN STRONG TO SEVERE WITH DEEP
LYR SHEAR NEAR 40 KTS. IN FACT...THE NEW SPC OUTLOOK FOR SUN AS
SHIFTED THE NRN EDGE OF MARGINAL RISK FOR SVR STORMS AS FAR N AS SRN
MNM COUNTY. POPS WL DIMINISH FM THE NW BY MID/LATE AFTN FOLLOWING
ARRIVAL OF SUBSIDENCE/MID LVL DRYING FOLLOWING THE SHRTWV.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 PM EDT SAT AUG 1 2015
IMPACTS...COOLER TEMPERATURES AND GREATER MOISTURE WILL HAVE A
POSITIVE IMPACT ON FIRE WEATHER...AT LEAST SOMEWHAT LOWERING
CONCERNS.
A TROUGH/COLD FRONT AND ASSOCIATED PRECIPITATION WILL BE MOSTLY OUT
OF THE AREA BY 00Z MON AS THE UPPER LOW THAT HAS BEEN SITTING OVER
HUDSON BAY MOVES S INTO ONTARIO. AS THE LOW MOVES FROM EXTREME NRN
ONTARIO AT 00Z MON TO THE ONTARIO/QUEBEC BORDER E OF LAKE SUPERIOR
BY 00Z WED...THE CORE OF COLDEST AIR (850MB TEMPS OF 3-4C) WILL
SLIDE INTO THE CWA. THE COLDER MID LEVELS WILL ALLOW FOR CONVECTIVE
SHOWERS MON THROUGH TUE AS LOW LEVEL MOISTURE WILL BE INCREASED AND
SUBTLE SHORTWAVES WILL BE MOVING THROUGH. SFC TEMPS WILL BE 7-10
DEGREES BELOW NORMAL WITH HIGHS IN THE MID 60S TO MID 70S. LOWS WILL
BE FROM THE MID 40S INLAND TO THE MID 50S NEAR THE GREAT LAKES.
TUE NIGHT THROUGH WED NIGHT WILL SEE A SFC RIDGE MOVE
OVERHEAD...WITH NO PRECIP EXPECTED. TEMPS MAY BE A DEGREE OR TWO
WARMER THAN TUE WITH HIGHS IN THE UPPER 60S TO LOW 70S. THERE WILL
STILL BE ENOUGH MOISTURE TUE NIGHT TO KEEP TEMPS FROM FALLING INTO
THE 30S AND WED NIGHT MAY SEE INCREASING CLOUD COVER AND RETURN FLOW
TO KEEP TEMPS FROM FALLING TO CONCERNING LEVELS.
THE REST OF THE PERIOD THU THROUGH SAT IS QUITE A BIT MORE UNCERTAIN
IN EXACT DETAILS AS CONDITIONS LOOK TO BE DRIVEN LARGELY BY
SHORTWAVES. SLIGHT CHANCES OF PRECIP EACH DAY AS GIVEN BY CONSENSUS
GUIDANCE IS REASONABLE...SO WILL LEAVE THAT IN THE FORECAST.
ALSO...TEMPERATURES LOOK TO REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 747 PM EDT SAT AUG 1 2015
WITH THE LOSS OF DIURNAL HEATING...WINDS WILL DIMINISH EARLY THIS
EVENING. ALTHOUGH A PASSING DISTURBANCE MAY BRING SOME -SHRA TO
UPPER MI LATE TONIGHT...LOW-LEVEL DRY AIR INDICATES VFR CONDITIONS
WILL PREDOMINATE EVEN IF ANY OF THE SHOWERS PASS OVER
KIWD/KCMX/KSAW. THERE WILL ALSO BE SOME MARGINAL LLWS OVERNIGHT WITH
A STRENGTHENING WSW FLOW ABOVE NEAR SFC STABLE LAYER. APPROACH OF A
STRONGER DISTURBANCE ON SUN WILL BRING A BETTER CHC OF SHRA AND
PROBABLY SOME TS...BUT CONFIDENCE IN TS OCCURRING AT ANY OF THE
TERMINALS IS LOW ENOUGH AT THIS POINT TO PRECLUDE A MENTION. VFR
CONDITIONS SHOULD CONTINUE ON SUN...BUT IF THERE IS BRIEF MDT/HVY
RAINFALL...MVFR AND PERHAPS EVEN IFR CONDITIONS COULD OCCUR FOR A
SHORT TIME.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 323 PM EDT SAT AUG 1 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A PAIR OF TROFS
ACROSS LAKE SUPERIOR TONIGHT AND SUN. WINDS WILL GENERALLY BE IN THE
10-20KT RANGE. HI PRES FROM THE CANADIAN PRAIRIES WILL MOVE OVER THE
REGION THROUGH MOST OF NEXT WEEK...KEEPING WINDS UNDER 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
952 PM MDT SAT AUG 1 2015
.UPDATE...
HEAVY RAIN THREAT IS ENDING ACROSS N/C NEW MEXICO. MAINLY
STRATIFORM TYPE OF EVENT WITH EMBEDDED CONVECTION DURING THE REST
OF THE OVERNIGHT. LOOKS LIKE THE MAIN BAND ACROSS WESTERN/CENTRAL
NM SHOULD SHIFT NORTHWARD DURING THE OVERNIGHT ALTHOUGH MAY JUST
DIE OUT OVER CENTRAL AREAS. UPDATED POPS AND ENDED THE FLASH
FLOOD WATCH.
50
&&
.PREV DISCUSSION...610 PM MDT SAT AUG 1 2015...
.AVIATION...
00Z TAF CYCLE
THE MONSOON MOISTURE PLUME WILL REMAIN ACTIVE TONIGHT WITH
SCT TO NMRS SHRA/TS THROUGH EVENING WITH WET MICROBURSTS LIKELY.
A DISTURBANCE PASSING NEWD OVER THE GREAT BASIN...AND ANOTHER ONE
EXITING SEWD FROM THE CENTRAL ROCKIES SHOULD KEEP SHOWERS AND
STORMS ACTIVE OVER W AND NE PARTS OF NM AFTER MIDNIGHT. A TRUSTED
MESOSCALE MODEL IS BRINGING ONE CLUSTER OF CELLS NEWD THROUGH THE
KABQ AND KSAF AREAS AROUND MIDNIGHT. ANOTHER ROUND OF SCT TO NMRS
SHRA/TS IS PROGGED TO IMPACT MUCH OF THE FORECAST AREA WITH LOWEST
PROBABILITIES AT KROW AND HIGHEST PROBABILITIES AT
KGUP...KFMN...KSAF AND KLVS.
44
&&
.PREV DISCUSSION...332 PM MDT SAT AUG 1 2015...
.SYNOPSIS...
AN ACTIVE MONSOON PATTERN IS EXPECTED TO PERSIST THROUGH THE
REMAINDER OF THE WEEKEND. SLOW-MOVING STORMS CAPABLE OF PRODUCING
TORRENTIAL RAINFALL AND FLASH FLOODING WILL REMAIN A CONCERN THIS
AFTERNOON AND EARLY TONIGHT AND AGAIN SUNDAY...ESPECIALLY IN NORTH
CENTRAL TO NORTHWEST PARTS OF NEW MEXICO. DRIER AND MORE STABLE
AIR WILL ATTEMPT TO WORK WEST BEGINNING MONDAY...SIGNIFICANTLY
LOWERING THE OVERALL COVERAGE OF STORMS AND FLASH FLOOD THREAT.
FEWER STORMS WILL TRANSLATE INTO A DAY TO DAY WARMING TREND NEXT
WEEK...AS WELL.
&&
.DISCUSSION...
SLOW-MOVING THUNDERSTORMS HAVE BEEN FOCUSED SQUARELY WITHIN THE
FLASH FLOOD WATCH THUS FAR...WITH TREMENDOUSLY IMPRESSIVE RAINFALL
RATES AS HIGH AS 3.3 INCHES PER HOUR AS MEASURED BY A PERSONAL
WEATHER STATION ON THE NORTHWEST SIDE OF SANTA FE. GENERALLY 1 TO
3 INCH PER HOUR RATES LIKELY WITH JUST ABOUT ANY WELL-DEVELOPED
STORM. MAY CONSIDER EXPANDING WATCH TO INCLUDE NE/EC AREAS
ALTHOUGH COVERAGE EAST OF THE CENTRAL MOUNTAIN CHAIN SHOULD BE
MORE ISOLATED TO SCATTERED. BUT RECENT RUNS OF THE HRRR CONTINUE
TO SUGGEST SMALL MCS-LIKE FEATURE ORGANIZING BETWEEN CLAYTON AND
CONCHAS DAM ROLLING TOWARD TUCUMCARI-LOGAN LATER THIS EVENING.
THIS WOULD ONE AREA OF CONCERN GIVEN VERY HEAVY RAIN PAST TWO
DAYS. WEAKNESS IN THE 500MB RIDGE NEAR THE NM/CO LINE ALSO A
PLAYER BUT VERY DIFFICULT TO TRACK BEYOND 12 HOURS.
OTHERWISE...WE`RE NOW MOVING INTO OUTFLOW BOUNDARY INTERACTION
TIME OF DAY FOR VALLEY LOCATIONS CENTRAL/WEST. AIR MASS PLENTY
MOIST WITH PRECIPITABLE WATER VALUES RANGING FROM 1.2 INCHES NW
TO 1.5 INCHES NEAR THE NM/TX LINE. A POCKET OF RELATIVELY LOWER
PWAT AIR /ONE 1 INCH OR SLIGHTLY LESS/ ANALYZED OVER THE LOWER RIO
GRANDE VALLEY TO UPPER GILA HAS KEPT COVERAGE A BIT LOWER THERE
BUT SUBTLE GRADIENTS.
GOING INTO SUNDAY...VERY LITTLE CHANGE TO OVERALL ORIENTATION OF
THE MONSOON PLUME BENEATH VERY WEAK STEERING CURRENTS. LEAST
FAVORED REGION WILL CONTINUE TO BE THE SOUTHEAST CORNER...WHILE
NC TO WC AREAS AGAIN FAVORED IN ADDITION TO THE SW THAT COULD SEE
A BUMP IN COVERAGE AS COMPARED TO TODAY.
THEREAFTER...WE HAVE BEGUN TO REFLECT A MARKED DECREASE IN STORM
COVERAGE MONDAY AND ESPECIALLY TUESDAY THROUGH THURSDAY. THIS AS
THE ANTICYCLONIC BELT OF WESTERLIES ELONGATES WEST-EAST AND SHIFTS
SLIGHTLY SOUTH PLACING THE AREA UNDER A DRIER WESTERLY FLOW
REGIME. THAT SAID...THE LAST DRYING EPISODE WAS POORLY HANDLED BY
VIRTUALLY ALL THE NWP MODELS AS THEY TEND TO DRY OUR MOIST
RESIDENT AIR MASS TOO QUICKLY. SO WE WILL PROCEED WITH A LITTLE
PRUDENCE...BUT DEFINITELY TRENDING FORECAST TOWARD MUCH FEWER
STORMS NEXT WEEK. IF THE MODELS ARE CORRECT WE WILL STRUGGLE TO
DEVELOP A STORM ANYWHERE BY MID- WEEK. THAT IN TURN WILL ALLOW FOR
A DAY TO DAY WARMING TREND. COULD SEE OUR NEXT BACKDOOR SURGE
THUR/FRI THEN WE START THE MOISTENING CYCLE OVER. KJ
&&
.FIRE WEATHER...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL FOCUS ON
NORTHERN AND WESTERN NEW MEXICO TODAY AND SUNDAY...WITH FURTHER
DEVELOPMENT EAST OF THE CENTRAL MOUNTAIN CHAIN. STEERING FLOW FROM
THE UPPER LEVEL HIGH RECENTERING OVER THE SOUTHERN PORTION OF THE
STATE WILL STEER SLOW MOVING NORTH TO NORTHEAST STORMS ACROSS
NORTHWESTERN TO NORTH CENTRAL AREAS WHERE FLASH FLOODING WILL
CONTINUE TO BE A MAJOR CONCERN THROUGHOUT THE REMAINDER OF THE
WEEKEND.
LOOK FOR A DRIER AIR MASS TO FILTER INTO THE STATE MONDAY THROUGH
THURSDAY AS THE UPPER LEVEL HIGH OVER SOUTHERN NEW MEXICO SHIFTS
WESTWARD FILTERING IN DRIER AIR FROM THE PACIFIC. SHOWER AND
THUNDERSTORM ACTIVITY WILL DOWNTREND AS TEMPERATURES CREEP BACK TO
NORMAL/ABOVE NORMAL READINGS. EXPECT HAINES VALUES TO INCREASE TO
THE 5 AND 6 VALUES ALONG WITH DECREASING MIN RH VALUES. STORM
ACTIVITY WILL BE LIMITED TO HIGHER TERRAIN AREAS AND ADJACENT LOWER
ELEVATION AREAS. THE MOISTURE PLUME LOOKS TO MAKE ITS RETURN BY THE
FOLLOWING WEEKEND WITH AN INCREASE IN WETTING PRECIPITATION CHANCES
ACROSS THE WEST AND NORTH AS THE UPPER LEVEL HIGH STARTS TO SHIFT
EASTWARD.
EXPECT POOR VENT RATES ACROSS THE NORTH THE REMAINDER OF THE WEEKEND
WITH IMPROVEMENTS BY MONDAY THROUGH THURSDAY. MIN RH VALUES WILL
DROP INTO THE UPPER TEENS BY THE MIDWEEK BUT OVERNIGHT RECOVERIES
WILL REMAIN GOOD. 32
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
50
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
610 PM MDT SAT AUG 1 2015
.AVIATION...
00Z TAF CYCLE
THE MONSOON MOISTURE PLUME WILL REMAIN ACTIVE TONIGHT WITH
SCT TO NMRS SHRA/TS THROUGH EVENING WITH WET MICROBURSTS LIKELY.
A DISTURBANCE PASSING NEWD OVER THE GREAT BASIN...AND ANOTHER ONE
EXITING SEWD FROM THE CENTRAL ROCKIES SHOULD KEEP SHOWERS AND
STORMS ACTIVE OVER W AND NE PARTS OF NM AFTER MIDNIGHT. A TRUSTED
MESOSCALE MODEL IS BRINGING ONE CLUSTER OF CELLS NEWD THROUGH THE
KABQ AND KSAF AREAS AROUND MIDNIGHT. ANOTHER ROUND OF SCT TO NMRS
SHRA/TS IS PROGGED TO IMPACT MUCH OF THE FORECAST AREA WITH LOWEST
PROBABILITIES AT KROW AND HIGHEST PROBABILITIES AT
KGUP...KFMN...KSAF AND KLVS.
44
&&
.PREV DISCUSSION...332 PM MDT SAT AUG 1 2015...
.SYNOPSIS...
AN ACTIVE MONSOON PATTERN IS EXPECTED TO PERSIST THROUGH THE
REMAINDER OF THE WEEKEND. SLOW-MOVING STORMS CAPABLE OF PRODUCING
TORRENTIAL RAINFALL AND FLASH FLOODING WILL REMAIN A CONCERN THIS
AFTERNOON AND EARLY TONIGHT AND AGAIN SUNDAY...ESPECIALLY IN NORTH
CENTRAL TO NORTHWEST PARTS OF NEW MEXICO. DRIER AND MORE STABLE
AIR WILL ATTEMPT TO WORK WEST BEGINNING MONDAY...SIGNIFICANTLY
LOWERING THE OVERALL COVERAGE OF STORMS AND FLASH FLOOD THREAT.
FEWER STORMS WILL TRANSLATE INTO A DAY TO DAY WARMING TREND NEXT
WEEK...AS WELL.
&&
.DISCUSSION...
SLOW-MOVING THUNDERSTORMS HAVE BEEN FOCUSED SQUARELY WITHIN THE
FLASH FLOOD WATCH THUS FAR...WITH TREMENDOUSLY IMPRESSIVE RAINFALL
RATES AS HIGH AS 3.3 INCHES PER HOUR AS MEASURED BY A PERSONAL
WEATHER STATION ON THE NORTHWEST SIDE OF SANTA FE. GENERALLY 1 TO
3 INCH PER HOUR RATES LIKELY WITH JUST ABOUT ANY WELL-DEVELOPED
STORM. MAY CONSIDER EXPANDING WATCH TO INCLUDE NE/EC AREAS
ALTHOUGH COVERAGE EAST OF THE CENTRAL MOUNTAIN CHAIN SHOULD BE
MORE ISOLATED TO SCATTERED. BUT RECENT RUNS OF THE HRRR CONTINUE
TO SUGGEST SMALL MCS-LIKE FEATURE ORGANIZING BETWEEN CLAYTON AND
CONCHAS DAM ROLLING TOWARD TUCUMCARI-LOGAN LATER THIS EVENING.
THIS WOULD ONE AREA OF CONCERN GIVEN VERY HEAVY RAIN PAST TWO
DAYS. WEAKNESS IN THE 500MB RIDGE NEAR THE NM/CO LINE ALSO A
PLAYER BUT VERY DIFFICULT TO TRACK BEYOND 12 HOURS.
OTHERWISE...WE`RE NOW MOVING INTO OUTFLOW BOUNDARY INTERACTION
TIME OF DAY FOR VALLEY LOCATIONS CENTRAL/WEST. AIR MASS PLENTY
MOIST WITH PRECIPITABLE WATER VALUES RANGING FROM 1.2 INCHES NW
TO 1.5 INCHES NEAR THE NM/TX LINE. A POCKET OF RELATIVELY LOWER
PWAT AIR /ONE 1 INCH OR SLIGHTLY LESS/ ANALYZED OVER THE LOWER RIO
GRANDE VALLEY TO UPPER GILA HAS KEPT COVERAGE A BIT LOWER THERE
BUT SUBTLE GRADIENTS.
GOING INTO SUNDAY...VERY LITTLE CHANGE TO OVERALL ORIENTATION OF
THE MONSOON PLUME BENEATH VERY WEAK STEERING CURRENTS. LEAST
FAVORED REGION WILL CONTINUE TO BE THE SOUTHEAST CORNER...WHILE
NC TO WC AREAS AGAIN FAVORED IN ADDITION TO THE SW THAT COULD SEE
A BUMP IN COVERAGE AS COMPARED TO TODAY.
THEREAFTER...WE HAVE BEGUN TO REFLECT A MARKED DECREASE IN STORM
COVERAGE MONDAY AND ESPECIALLY TUESDAY THROUGH THURSDAY. THIS AS
THE ANTICYCLONIC BELT OF WESTERLIES ELONGATES WEST-EAST AND SHIFTS
SLIGHTLY SOUTH PLACING THE AREA UNDER A DRIER WESTERLY FLOW
REGIME. THAT SAID...THE LAST DRYING EPISODE WAS POORLY HANDLED BY
VIRTUALLY ALL THE NWP MODELS AS THEY TEND TO DRY OUR MOIST
RESIDENT AIR MASS TOO QUICKLY. SO WE WILL PROCEED WITH A LITTLE
PRUDENCE...BUT DEFINITELY TRENDING FORECAST TOWARD MUCH FEWER
STORMS NEXT WEEK. IF THE MODELS ARE CORRECT WE WILL STRUGGLE TO
DEVELOP A STORM ANYWHERE BY MID- WEEK. THAT IN TURN WILL ALLOW FOR
A DAY TO DAY WARMING TREND. COULD SEE OUR NEXT BACKDOOR SURGE
THUR/FRI THEN WE START THE MOISTENING CYCLE OVER. KJ
&&
.FIRE WEATHER...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL FOCUS ON
NORTHERN AND WESTERN NEW MEXICO TODAY AND SUNDAY...WITH FURTHER
DEVELOPMENT EAST OF THE CENTRAL MOUNTAIN CHAIN. STEERING FLOW FROM
THE UPPER LEVEL HIGH RECENTERING OVER THE SOUTHERN PORTION OF THE
STATE WILL STEER SLOW MOVING NORTH TO NORTHEAST STORMS ACROSS
NORTHWESTERN TO NORTH CENTRAL AREAS WHERE FLASH FLOODING WILL
CONTINUE TO BE A MAJOR CONCERN THROUGHOUT THE REMAINDER OF THE
WEEKEND.
LOOK FOR A DRIER AIR MASS TO FILTER INTO THE STATE MONDAY THROUGH
THURSDAY AS THE UPPER LEVEL HIGH OVER SOUTHERN NEW MEXICO SHIFTS
WESTWARD FILTERING IN DRIER AIR FROM THE PACIFIC. SHOWER AND
THUNDERSTORM ACTIVITY WILL DOWNTREND AS TEMPERATURES CREEP BACK TO
NORMAL/ABOVE NORMAL READINGS. EXPECT HAINES VALUES TO INCREASE TO
THE 5 AND 6 VALUES ALONG WITH DECREASING MIN RH VALUES. STORM
ACTIVITY WILL BE LIMITED TO HIGHER TERRAIN AREAS AND ADJACENT LOWER
ELEVATION AREAS. THE MOISTURE PLUME LOOKS TO MAKE ITS RETURN BY THE
FOLLOWING WEEKEND WITH AN INCREASE IN WETTING PRECIPITATION CHANCES
ACROSS THE WEST AND NORTH AS THE UPPER LEVEL HIGH STARTS TO SHIFT
EASTWARD.
EXPECT POOR VENT RATES ACROSS THE NORTH THE REMAINDER OF THE WEEKEND
WITH IMPROVEMENTS BY MONDAY THROUGH THURSDAY. MIN RH VALUES WILL
DROP INTO THE UPPER TEENS BY THE MIDWEEK BUT OVERNIGHT RECOVERIES
WILL REMAIN GOOD. 32
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR THE FOLLOWING
ZONES... NMZ501>507-510>517-523-528-529-531>534.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1143 PM MDT THU JUL 30 2015
.AVIATION...
06Z TAF CYCLE
SHRA/TSRA CONTINUE ACROSS MUCH OF THE EASTERN PLAINS AND PORTIONS
OF NW NM. THE FORMER IS MOVING TOWARD THE N AND NE AND THE LATTER
IS MOVING TOWARD THE W AND NW. THE ACTIVITY ACROSS THE NW SHOULD
CONTINUE FOR ANOTHER COUPLE OF HOURS...BUT LIKE LAST NIGHT...THE
ACTIVITY ACROSS THE EAST MAY PERSIST THROUGH SUNRISE. MVFR
CIGS/VSBYS WILL BE POSSIBLE WITH THE STRONGEST ACTIVITY. SHOULD
STORMS DIMINISH EARLIER...COULD SEE MVFR/IFR CIGS ACROSS PORTIONS
OF THE NE PLAINS. ANOTHER ROUND OF SHRA/TSRA IS EXPECTED ON
FRIDAY FAVORING THE HIGH TERRAIN AND PORTIONS OF NE NM. STEERING
FLOW WILL BE LIGHT...PERHAPS LIGHTER THAN TODAY AS THE UPPER HIGH
REMAINS OVERHEAD. MVFR CIGS AND BRIEF MT OBSCURATIONS WILL BE
POSSIBLE FRI AFTN.
34
&&
.PREV DISCUSSION...906 PM MDT THU JUL 30 2015...
.UPDATE...
UPDATED POP/WEATHER GROUPINGS IN THE GRIDDED FORECAST FOR REST OF
TONIGHT. ALSO UPDATED THE FLASH FLOOD WATCH BY ELIMINATING
WESTERN/CENTRAL AREAS. LATEST RADAR/SATELLITE IMAGERY AND TO A
CERTAIN DEGREE MODELING SHOWS THE MAIN THREAT FOR HEAVY RAIN
ACROSS EASTERN AREAS. THUS LEFT THE WATCH UP THERE. MODELS SEEM TO
BE OVERDOING CONDITIONS ACROSS WESTERN/CENTRAL AREAS DESPITE SOME
FOCUSING WAVE FEATURES. THE LATEST HRRR HAS BACK OFF QPF NUMBERS
ACROSS SW/WC HIGHLANDS ALTHOUGH THERE IS A WAVE POISED TO IMPACT
THOSE AREAS TONIGHT. SUSPECT THE RAINFALL WILL BE MORE STRATIFORM
WITH LESS OF A HEAVY RAIN THREAT. SIMILARLY FOR NW AREAS WHERE
THERE IS SOME ONGOING RAINFALL WITHIN A MID LEVEL DEFORMATION
AREA. VERY MOIST ENVIRONMENT SO IT DOESNT TAKE MUCH TO PRODUCE A
RAIN SHOWER.
50
&&
.PREV DISCUSSION...240 PM MDT THU JUL 30 2015...
.SYNOPSIS...
SHOWERS AND STORMS WITH LOCALLY HEAVY RAINFALL WILL CONTINUE TO
IMPACT NEW MEXICO THROUGH THE WEEKEND. THE FLASH FLOOD POTENTIAL
WILL REMAIN ELEVATED AS SLOW-MOVING STORMS DROP A QUICK 1 TO 2
INCHES OF RAIN. AREAS OF STEEP TERRAIN...BURNED FORESTS...URBAN
DRAINAGES...AND AREAS THAT PICK UP DAILY ROUNDS OF HEAVY RAIN WILL
BE THE MOST SUSCEPTIBLE. A VERY SLOW DRYING AND WARMING TREND IS
EXPECTED BEGINNING NEXT WEEK.
&&
.DISCUSSION...
THE CLIMATOLOGICAL PEAK FOR DEEP ATMOSPHERIC MOISTURE AND FLASH
FLOOD POTENTIAL IS CERTAINLY DELIVERING AS WE NEAR THE END OF JULY
2015. A REMNANT CONVECTIVE VORTEX FROM LAST NIGHT MOVING SLOWLY
NORTH ALONG THE CONT DVD IS FOCUSING REDEVELOPMENT TODAY. ANOTHER
AREA OF MOISTURE CONVERGENCE IS FIRING UP FROM LINCOLN COUNTY NORTH
INTO TORRANCE COUNTY WHERE RADAR-BASED STORM TOTAL ACCUMULATION IS
ALREADY NEAR 3 INCHES IN SOME LOCALES. THE WEAKEST STEERING FLOW
IS FOCUSED OVER NORTHERN NM WHERE DEFORMATION STRETCHES FROM WEST
TO EAST OVER THE HIGH TERRAIN. ANY ACTIVITY THERE WILL BE NEARLY
STATIONARY AND PRODUCE TORRENTIAL RAINFALL. ALL THESE AREAS ARE
UNDER THE FLASH FLOOD WATCH AND NO CHANGES WILL BE MADE. SOME
MINOR RIVER FLOODING IS ALSO POSSIBLE ALONG TRIBUTARIES TO MAIN
STEM RIVERS SUCH AS THE RIO GRANDE AND PECOS THROUGH THE WEEKEND.
EXPECT LITTLE TO NO CHANGE FRIDAY...EXCEPT PERHAPS A GREATER FOCUS
FOR HEAVY RAINFALL FARTHER NORTHWEST TOWARD THE FOUR CORNERS. THIS
WEEKEND WILL SEE ELEVATED FLASH FLOOD POTENTIAL AS THE UPPER HIGH
ESTABLISHES FIRMLY OVERHEAD. EACH AFTERNOON OF HEAVY RAINFALL IN
THE SAME AREAS WILL EXACERBATE FLASH FLOOD POTENTIAL.
A SLOW WARMING AND DRYING TREND IS STILL EXPECTED AS WE HEAD INTO
EARLY NEXT WEEK WITH NO ADDITIONAL INFLUX OF MOISTURE NOTED. THE
RECYCLING PROCESS WILL BE THE DOMINANT PLAYER...WHICH WILL BE VERY
EFFICIENT. NASA SPORT LIS SHOWS MOIST SOILS ARE EXPANDING OVER A
LARGER AREA OF NM AND TO DEEPER LAYERS. OVERALL...CONDITIONS ARE
LOOKING VERY TYPICAL OF A MATURE MONSOON PATTERN THROUGH EARLY
AUGUST.
GUYER
&&
.FIRE WEATHER...
UPPER HIGH CENTER ATTEMPTING TO BECOME ESTABLISHED OVER NEW MEXICO
THIS AFTERNOON...AND MODELS PERSIST ON IT LINGERING OVER THE STATE
FOR MUCH OF THE UPCOMING WEEK...ALTHOUGH IT/S LIKELY TO WOBBLE
AROUND A BIT. MOISTURE TO REMAIN TRAPPED UNDER THE RIDGE...BUT
SHOULD VERY SLOWLY WARM AND DRY NEXT WEEK. CELL MOTION COULD BE
SOMEWHAT ERRATIC FOR THE REST OF THIS AFTERNOON AND TONIGHT...BUT
GENERALLY NORTHWEST AND NORTH WEST OF THE RGV AND NORTH TO NORTHEAST
EAST OF THE RGV. MOVEMENT AND SPEED WILL TREND TO SLOWER AND MORE
ERRATIC FRIDAY AND INTO THE WEEKEND WITH THE HIGH CENTER OVERHEAD.
THEREFORE...LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AT LEAST THROUGH
FRIDAY.
HIGH TEMPERATURES TO VARY FROM MOSTLY BELOW AVERAGE THROUGH SUNDAY
TO NEAR TO ABOVE AVERAGE NEXT MONDAY THROUGH THURSDAY. WHILE MIN RH
VALUES WILL TREND DOWNWARD NEXT WEEK...OVERNIGHT RECOVERIES FORECAST
TO REMAIN EXCELLENT.
VENT RATES OVER PORTIONS OF THE NORTH WILL BE FAIR TO POOR THROUGH
SUNDAY. POOR RATES ARE FORECAST FOR THE NORTHEAST AND SOUTHWEST
MONDAY.
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH UNTIL 4 AM MDT FRIDAY FOR THE FOLLOWING ZONES...
NMZ512>515-523-527>537.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1005 PM EDT SAT AUG 1 2015
.SYNOPSIS...
A WEAK FRONT WILL REMAIN STALLED ACROSS THE COASTAL CAROLINAS
THIS WEEKEND...PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS NEAR
THE COAST. THE FRONT SHOULD DISSIPATE ON MONDAY. BERMUDA HIGH
PRESSURE WELL OFFSHORE WILL BUILD WESTWARD NEXT WEEK. TEMPERATURES
WILL REMAIN SEASONABLE TO SLIGHTLY ABOVE NORMAL THROUGH THE
WEEKEND INTO NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 1000 PM SATURDAY...FORECAST SOUNDINGS FROM BOTH THE NAM AND
GFS SHOW A THIN LAYER OF UNSTABLE AIR AT THE TOP OF TODAY`S DEEP
MIXED LAYER ACROSS THE PEE DEE REGION. THIS IS NOT A SITUATION I
WOULD HAVE ANTICIPATED CONVECTION TO DEVELOP WITHIN GIVEN ELEVATED
INSTABILITY BASED AROUND 6500 FEET AGL AND BONE-DRY AIR AT AND
ABOVE 700 MB. NEVERTHELESS THERE ARE SHOWERS WITH LOCALLY HEAVY
RAIN DEVELOPING ALONG THE I-95 CORRIDOR FROM FLORENCE NORTHWARD TO
NEAR BINGHAM IN WESTERN DILLON COUNTY. INFRARED SATELLITE SHOWS
ADDITIONAL MID- LEVEL CLOUD COVER EXTENDING NORTHWARD INTO ROBESON
COUNTY NC...SO I HAVE TO AT LEAST CONSIDER THE POSSIBILITY FOR
SHOWERS TO DEVELOP THIS FAR NORTH AS WELL.
AT THE SURFACE HIGHER DEWPOINTS HAVE RETURNED WESTWARD INTO THE
INTERIOR COASTAL PLAIN WITH 70S SHOWING UP AGAIN IN LUMBERTON...
MARION AND FLORENCE. THIS MOISTURE MAY BE TOO THIN TO BE FEEDING
THE CONVECTION DIRECTLY...AS THE SURFACE IS LIKELY DECOUPLED FROM
THE ATMOSPHERE ALOFT.
LATEST HRRR MODEL RUNS DO NOT REALLY SHOW THIS CURRENT ACTIVITY
WELL...ALTHOUGH INTERESTINGLY THE 00Z NAM DOES. THE NAM MOVES THE
SHOWERS EASTWARD TOWARD THE COAST...DISSIPATING THE CONVECTION
BETWEEN 06-09Z NEAR MYRTLE BEACH.
AT 500 MB THE CAROLINAS FORM THE BASE OF A BROAD TROUGH EXTENDING
DOWN FROM HUDSON BAY CANADA. PLENTY OF DRY AIR AT AND ABOVE 700 MB
SHOULD CONTINUE ON WESTERLY WINDS OVERNIGHT. HIGH PRESSURE OVER
THE OHIO VALLEY WILL DRIFT EASTWARD INTO THE CENTRAL APPALACHIANS
SUNDAY MORNING. THIS WILL NUDGE OUR FRONT OFF THE COAST INTO THE
NEARSHORE WATERS BY DAYBREAK. MOISTURE TRAPPED WITHIN THE
DECOUPLED BOUNDARY LAYER WILL REMAIN TRAPPED OVERNIGHT...AND WITH
GOOD RADIATIONAL COOLING I ANTICIPATE PATCHY FOG WILL
DEVELOP...ESPECIALLY EAST OF I-95 WHERE DEWPOINTS ARE HIGHEST.
LOWS SHOULD FALL 70-74...WARMEST AT THE BEACHES.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...STATIONARY FRONT WILL REMAIN IN AREA
SUNDAY BEFORE DISSIPATING IN PLACE ON MONDAY. MEANWHILE...A
BROAD...FLAT-ISH H5 TROUGH WILL REMAIN ANCHORED IN PLACE OVER
EASTERN CONUS. GUIDANCE STILL SHOWING PLENTIFUL DRY AIR ALOFT
WHICH WILL LIMIT EXTENT OF CONVECTION DESPITE PRESENCE OF FRONTAL
BOUNDARY AND THE OCCASIONAL SHORT WAVE THAT WILL DROP INTO THE
BASE OF THE UPPER TROUGH. AIR ALOFT IS DRIEST INLAND...SO WILL
SHOW A DECREASING GRADIENT IN POPS NW FROM THE COAST FOR BOTH
DAYS. DUE TO OVERALL LIMITED MOISTURE ALOFT...WILL KEEP POPS
CAPPED AT LOW CHANCE FOR THE IMMEDIATE COAST FOR BOTH DAYS...WITH
FAR INLAND AREAS BEING POSSIBLY TOO DRY TO SEE ANY SIGNIFICANT
RAINFALL.
TEMPERATURES WILL REMAIN ABOVE CLIMO THROUGH THE SHORT TERM AND
HEAT INDEX VALUES WILL LIKELY REACH AROUND A 100 OR SO BOTH
AFTERNOONS. HOWEVER...HEAT ADVISORY CRITERIA IS NOT EXPECTED TO
BE EXCEEDED.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY... WHAT LITTLE MOISTURE THERE WILL BE IN
PLACE ON TUESDAY WILL BE POOLED UP ALONG THE COAST. MINOR RAIN
CHANCES WILL BE FOCUSED THERE DURING AN OTHERWISE HOT AFTERNOON
PROVIDED IN PART BY A VERY WEAK RIDGE ALOFT. RAIN CHANCES REMAIN
SLOW ON WEDNESDAY AS THE FLOW ALOFT STAYS WEAK THOUGH THE SENSE OF
RIDGING WEAKENS. SO WILL KEEP POPS MINIMIZED BUT SHOW THEM AREA-
WIDE. RAIN CHANCES RAMP UP TO SCATTERED ON THURSDAY AS SOME WEAKLY
CYCLONIC CURVATURE OVERSPREADS THE REGION AND A SURFACE PIEDMONT
TROUGH TAKES SHAPE. ANOTHER LITTLE PIECE OF ENERGY WILL PROVIDE
SOME LIFT ON FRIDAY WHICH MAY BE ANOTHER FAIRLY ACTIVE DAY. ON
SATURDAY NOT ONLY WILL THERE BE CONTINUED DISTURBANCES IMPINGING
UPON THE AREA FROM THE NORTHWEST BUT A COLD FRONT WILL ALSO BE
MOVING INTO THE CAROLINAS. WEDNESDAY AND THURSDAY WILL BOTH SEE
RATHER HOT AFTERNOONS WHEREAS THE INCREASE IN CLOUDS LATE IN THE
PERIOD SHOULD TEMPER THINGS A BIT BACK TOWARDS CLIMO.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 23Z...LATEST SFC ANALYSIS SHOWS A STATIONARY FRONT DRAPED
BETWEEN THE INLAND AND COASTAL TERMINALS. CONVECTION FIRED UP ALONG
THIS BOUNDARY MAINLY NEAR AND OVER KILM THIS AFTERNOON. PLENTY OF LLVL
MOISTURE AVAILABLE FOR THE TONIGHT/OVERNIGHT PERIOD TRAPPED BENEATH
AN INVERSION AND WITH LIGHT WINDS ALSO EXPECTED CANNOT RULE OUT MVFR
CONDITIONS DUE TO FOG DEVELOPMENT...ESPECIALLY KILM. WILL MAKE MENTION
AFTER 08Z IN ALL TERMINALS FOR FOG AND MVFR CONDITIONS. VFR TO RETURN
AFTER 12Z AND SUNDAY WILL BE SOMEWHAT LIKE TODAY WITH THE STATIONARY
FRONT DRAPED ACROSS THE REGION AND THE CHANCE OF ISOLATED SHOWER OR
THUNDERSTORM POSSIBLE DURING THE DAY. WILL KEEP VFR IN ALL TERMINALS
BUT CANNOT RULE OUT A BRIEF MVFR IN VSBY/CEILING IF CONVECTION OCCURS
OVER A TERMINAL.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH A
SLIGHT CHANCE AFTERNOON SHRA/TSRA.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 PM SATURDAY...A FRONT IS STALLED ACROSS THE COASTAL
PLAIN OF THE CAROLINAS THIS EVENING. HIGH PRESSURE OVER OHIO WILL
DRIFT EAST INTO THE CENTRAL APPALACHIANS LATE TONIGHT. THIS SHOULD
NUDGE THE FRONT EASTWARD AND INTO THE COASTAL WATERS LATE. SOUTH
TO SOUTHWEST WINDS THIS EVENING AS HIGH AS 15 KNOTS IN THE CAPE
FEAR AREA SHOULD DIMINISH TO LESS THAN 10 KNOTS AFTER
MIDNIGHT...THEN TURN NORTHWESTERLY LATE AS THE FRONT PUSHES OFF
THE COAST.
THE PRIMARY WAVE SET IS A 7-SECOND SOUTHERLY SWELL...WITH A
SMALLER 10-SECOND SOUTHEASTERLY SWELL SHOWING UP. THESE TWO WAVES
WILL CONTINUE INDEPENDENT OF THE WIND OVERNIGHT...WITH COMBINED
SEAS 2-4 FEET...HIGHEST OFFSHORE FROM CAPE FEAR.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...A STALLED FRONT WILL DISSIPATE OVER THE
EASTERN CAROLINAS ON MONDAY AS BERMUDA HIGH PRESSURE OFFSHORE
EXTENDS BACK WEST ACROSS THE WATERS. WINDS WILL SETTLE BACK INTO A
SWLY DIRECTION BY SUNDAY NIGHT AS THE FRONT WEAKENS AND
DISSIPATES. A SMALL CRAFT ADVISORY MAY BE REQUIRED MONDAY
AFTERNOON OR EVENING AS THE GRADIENT TIGHTENS WITH HIGH PRESSURE
BUILDING WEST ACROSS THE WATERS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...WIND AND SEAS RELAX ON TUESDAY AS
PIEDMONT TROUGHINESS PUSHES THE TIGHTER GRADIENT CAUSED BY THE
BERMUDA HIGH FURTHER OUT TO SEA. THOUGH SOME SWELL ENERGY MAY
REMAIN WE SHOULD DROP BELOW ADVISORY THRESHOLDS. THEREAFTER IT
LOOKS LIKE PRETTY STANDARD FARE FOR JULY WITH A SOUTHWESTERLY WIND
IN THE 10 TO 15 KT RANGE AND 2 TO 4 FT SEAS...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 200 AM SATURDAY...MINOR COASTAL FLOODING IS POSSIBLE DURING
THE NIGHT-TIME HIGH TIDE OVER THE NEXT COUPLE OF DAYS. THESE
HIGHER THAN NORMAL TIDES ARE THE RESULT OF THE PERIGEAN SPRING
TIDE AND A FULL MOON WHICH OCCURRED ON FRIDAY. DEPARTURES OF PLUS
1/2 TO 1 FOOT WILL BE ENOUGH TO PRODUCE A BRIEF PERIOD OF MINOR
COASTAL FLOODING. THE RISK IS HIGHEST FOR PORTIONS OF THE LOWER
CAPE FEAR RIVER TO INCLUDE DOWNTOWN WILMINGTON...WITH A LIKELY
PROBABILITY. THE BEACHES WILL APPROACH THE THRESHOLD FOR MINOR
COASTAL FLOODING AGAIN THIS EVE...BUT THIS WILL BE THE LAST TIME
THIS LUNAR CYCLE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...REK
NEAR TERM...TRA
SHORT TERM...REK
LONG TERM...MBB
AVIATION...MAC
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
138 PM EDT FRI JUL 31 2015
.SYNOPSIS...
A COLD FRONT WILL STALL ALONG THE COAST THROUGH THE WEEKEND. THE
FRONT WEAKENS EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE
AREA FROM THE ATLANTIC...AND AN INLAND TROUGH DEVELOPS TO THE
WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1235 PM FRIDAY...FRONTAL BOUNDARY REMAINS JUST SOUTH OF THE
NC COAST. HIGH-RESOLUTION MODELS SUCH AS THE HRRR AND RUC INDICATE
A RATHER PROUNOUNCED SEA BREEZE WILL DEVELOP DURING THE LATE
AFTERNOON HOURS. IN CONCERT WITH A DIGGING MID-LEVEL
TROUGH...EXPECT A GOOD COVERAGE OF SHOWERS/THUNDERSTORMS PRIMARY
OVER THE SOUTHERN HALF OF THE AREA AND MAINLY NEAR THE COAST THIS
AFTERNOON INTO THIS EVENING. MODERATE INSTABILITY IS FORECAST
WITH CAPES 1500-2000 J/KG AND LI`S -3 TO -5...BUT A COL IN THE
MID-LEVEL FLOW WILL LEAD TO VERY SLOW MOVEMENT OF ANY ACTIVITY
THAT DEVELOPS WITH POSSIBLE LOCALIZED HEAVY RAINFALL...GIVEN
PRECIPITABLE WATER VALUES OF AROUND 2 INCHES FROM THE 12Z MHX
SOUNDING. ONLY MINOR CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 3 AM FRIDAY...THE STALLED FRONT WILL CONT TO PROVIDE THE
FOCUS FOR SCT CONVECTION ALONG THE SRN TIER TONIGHT WITH MORE
ISOLD PRECIP TO THE N. SLIGHTLY COOLER TEMPS FOR INLAND AREAS
TONIGHT WITH LOWS IN THE UPR 60S TO NEAR 70 COASTAL PLAINS AND
THE LOWER AND MID 70S FOR COASTAL AREAS WITH PARTLY CLOUDY SKIES N
AND MOSTLY CLOUDY SKIES FOR SOUTHERN SXNS WITH BTR PRECIP CHCS.
&&
.LONG TERM /SATURDAY THROUGH FRIDAY/...
AS OF 330 AM FRI...WEAK COLD FRONT WILL STALL NEAT THE COAST
THROUGH THE WEEKEND WHILE BROAD TROUGHING DOMINATES ALOFT.
ATLANTIC HIGH PRESSURE WILL BUILD BACK IN EARLY TO MID NEXT WEEK.
SATURDAY AND SUNDAY...MODELS COMING INTO BETTER AGREEMENT WITH
RESPECT TO SHOWER/STORM CHANCES THIS WEEKEND. THE 31/00Z ECM HAS
CONTINUED TO TREND TOWARDS THE DRIER GFS SOLN. WILL FOLLOW
TRENDS OF DECREASING POPS TO LESS THAN 20 PERCENT FOR THE NORTHERN
AREAS AND 20-30 PERCENT ON THE COAST THROUGH THE WEEKEND. ANY
STORMS THAT DEVELOP COULD PRODUCE HEAVY RAIN PER HIGH LAYER MIX
RATIOS AND COLUMN PWATS AOA 2 INCHES ALONG THE COAST THROUGH THE
WEEKEND. TEMPS WILL BE TYPICALLY HOT WITH HIGHS IN THE LOW 90S
INLAND TO 80S COAST...WITH LOWS IN THE LOW/MID 70S INLAND TO UPR
70S COAST.
MONDAY...SIMILAR SCENARIO TO THE WEEKEND WITH BROAD TROUGHING AND
WASHED OUT FRONTAL BOUNDARY NEAR THE AREA. BEST SHOWER CHANCES
WILL AGAIN BE NEAR OR JUST OFFSHORE EARLY MONDAY...THEN SEA BREEZE
CONVERGENCE DURING THE AFTERNOON MAY PROMOTE SCT/ISO THUNDERSTORMS
FOR THE SECOND HALF OF THE DAY INLAND. STILL HOT AND MUGGY WITH
HIGHS IN THE LOW 90S INLAND TO 80S COAST.
TUESDAY THROUGH THURSDAY...WARMING TEMPS AS THICKNESSES AND TEMPS
BUILD WITH HIGHS CLIMBING INTO THE MID 90S (80S COAST). SOME MODEL
DIFFERENCES CONTINUE MID WEEK AS 31/00Z GFS CONTINUES TROUGHING
ALONG THE EAST COAST AND PUSHES A FRONT THROUGH THE AREA LATE
WED/THU WITH A WAVE DEVELOPING ALONG IT... WHILE THE ECMWF HAS
BERMUDA HIGH AS MAIN FEATURE AND THERMAL TROUGHING INLAND. WILL
TREND WITH WPC/ECMWF AND PREVIOUS FORECAST WITH HIGH OFFSHORE AND
PRED S/SW FLOW ACROSS THE AREA. WILL CONTINUE SC POPS...THINKING
PRIMARILY DIURNALLY DRIVEN AT THIS TIME AND MAINLY AWAY FROM THE
COAST.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 18Z SATURDAY/...
AS OF 130 PM FRIDAY...VFR CONDITIONS THROUGH MUCH OF THE TAF PERIOD.
SHOWERS AND THUNDERSTORMS SHOULD START TO DEVELOP LATER THIS
AFTERNOON ALONG THE SEA BREEZE/STALLED FRONT. THIS ACTIVITY SHOULD
STAY PRIMARILY EAST OF THE TAF SITES. BUT CAN NOT RULE OUT
PRECIPITATION MIGRATING CLOSER TO OAJ/EWN. PRECIPITATION SHOULD
DIMINISH THROUGH THE EVENING HOURS WITH CLOUDS ALSO ERODING THROUGH
THE OVERNIGHT...LINGERING MAINLY ALONG THE COAST. THEREFORE...THIS
MAY PROVIDE A BRIEF OPPORTUNITY FOR FOG TO DEVELOP ESPECIALLY
ACROSS OAJ/ISO DURING THE EARLY MORNING HOURS. FEEL EWN MAY HAVE
TOO MUCH CLOUD COVER STILL IN PLACE TO OBSERVE MUCH FOG. DEW
POINT DEPRESSIONS ACROSS THE NW MIGHT ALSO BE A BIT HIGH.
THEREFORE...HAVE EWN/PGV WITH A BIT HIGHER VSBYS AS COMPARED TO
OAJ/ISO. ANY LOW LEVEL MOISTURE SHOULD MIX OUT BY MID-MORNING
WITH MOSTLY CLEAR SKIES FOR MUCH OF SATURDAY. LIGHT AND VARIABLE
WINDS THROUGH THE TAF PERIOD.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...PRED VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. A FRONT WILL STALL NEAR THE COAST OR JUST OFFSHORE THROUGH
THE WEEKEND. ISOLATED TO SCT SHOWERS/TSTMS SAT THROUGH EARLY NEXT
WEEK...WITH BEST CHANCES AT EWN/OAJ. PATCHY FOG/STRATUS POSSIBLE
EACH NIGHT WITH LIGHT WINDS ESP FOR AREAS THAT RECEIVE RAINFALL.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1240 PM FRIDAY...STILL GENERALLY NORTHERLY WINDS OVER THE
COASTAL WATERS AND SOUNDS...ALTHOUGH SEEING WINDS VEER TO MORE
SOUTHEAST OVER THE FAR SOUTHERN WATERS. SPEEDS REMAIN LESS THAN
15 KNOTS WITH SEAS OF 3 TO 4 FEET. WILL SEE SOUTHWEST WINDS
DEVELOP WITH A FAIRLY PRONOUNCED SEA BREEZE THIS AFTERNOON OVER
SOUTHERN SECTIONS...WITH LIGHT NORTH WINDS CONTINUING NORTH OF
OCRACOKE. WINDS GRADUALLY BECOME SE TO S TONIGHT 10 KT OR LESS.
WINDS BECOME SW THROUGHOUT TOWARD SAT MORN HIGHEST SRN COASTAL
WATERS. SEAS WILL RANGE 2-4 FT TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...THE COLD FRONT WILL WASH OUT BY SAT WITH
SOUTHERLY FLOW ONCE AGAIN DEVELOPING. GRADIENT TIGHTENS THROUGH
THE DAY SAT WITH INCREASING SSW WINDS 10-15KT CONT INTO SUN. A
PERIOD OF MARGINAL SCA CONDITIONS LIKELY TO DEVELOP SUN
NIGHT...MAINLY SOUTH OF OREGON INLET...WITH WINDS INCREASING TO
15-25KT AND SEAS BUILDING TO 4-7FT. GUSTY SW WINDS EXPECTED TO
CONTINUE INTO TUE...WITH LINGERING 6FT SEAS POSSIBLE INTO TUE
NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JAC
NEAR TERM...CTC
SHORT TERM...JAC
LONG TERM...CQD/TL
AVIATION...TL/LEP
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1239 PM EDT FRI JUL 31 2015
.SYNOPSIS...
A COLD FRONT WILL STALL ALONG THE COAST THROUGH THE WEEKEND. THE
FRONT WEAKENS EARLY NEXT WEEK AS HIGH PRESSURE BUILDS INTO THE
AREA FROM THE ATLANTIC...AND AN INLAND TROUGH DEVELOPS TO THE
WEST.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1235 PM FRIDAY...FRONTAL BOUNDARY REMAINS JUST SOUTH OF THE
NC COAST. HIGH-RESOLUTION MODELS SUCH AS THE HRRR AND RUC INDICATE
A RATHER PROUNOUNCED SEA BREEZE WILL DEVELOP DURING THE LATE
AFTERNOON HOURS. IN CONCERT WITH A DIGGING MID-LEVEL
TROUGH...EXPECT A GOOD COVERAGE OF SHOWERS/THUNDERSTORMS PRIMARY
OVER THE SOUTHERN HALF OF THE AREA AND MAINLY NEAR THE COAST THIS
AFTERNOON INTO THIS EVENING. MODERATE INSTABILITY IS FORECAST
WITH CAPES 1500-2000 J/KG AND LI`S -3 TO -5...BUT A COL IN THE
MID-LEVEL FLOW WILL LEAD TO VERY SLOW MOVEMENT OF ANY ACTIVITY
THAT DEVELOPS WITH POSSIBLE LOCALIZED HEAVY RAINFALL...GIVEN
PRECIPITABLE WATER VALUES OF AROUND 2 INCHES FROM THE 12Z MHX
SOUNDING. ONLY MINOR CHANGES MADE TO CURRENT FORECAST.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
AS OF 3 AM FRIDAY...THE STALLED FRONT WILL CONT TO PROVIDE THE
FOCUS FOR SCT CONVECTION ALONG THE SRN TIER TONIGHT WITH MORE
ISOLD PRECIP TO THE N. SLIGHTLY COOLER TEMPS FOR INLAND AREAS
TONIGHT WITH LOWS IN THE UPR 60S TO NEAR 70 COASTAL PLAINS AND
THE LOWER AND MID 70S FOR COASTAL AREAS WITH PARTLY CLOUDY SKIES N
AND MOSTLY CLOUDY SKIES FOR SOUTHERN SXNS WITH BTR PRECIP CHCS.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
AS OF 330 AM FRI...WEAK COLD FRONT WILL STALL NEAT THE COAST
THROUGH THE WEEKEND WHILE BROAD TROUGHING DOMINATES ALOFT.
ATLANTIC HIGH PRESSURE WILL BUILD BACK IN EARLY TO MID NEXT WEEK.
SATURDAY AND SUNDAY...MODELS COMING INTO BETTER AGREEMENT WITH
RESPECT TO SHOWER/STORM CHANCES THIS WEEKEND. THE 31/00Z ECM HAS
CONTINUED TO TREND TOWARDS THE DRIER GFS SOLN. WILL FOLLOW
TRENDS OF DECREASING POPS TO LESS THAN 20 PERCENT FOR THE NORTHERN
AREAS AND 20-30 PERCENT ON THE COAST THROUGH THE WEEKEND. ANY
STORMS THAT DEVELOP COULD PRODUCE HEAVY RAIN PER HIGH LAYER MIX
RATIOS AND COLUMN PWATS AOA 2 INCHES ALONG THE COAST THROUGH THE
WEEKEND. TEMPS WILL BE TYPICALLY HOT WITH HIGHS IN THE LOW 90S
INLAND TO 80S COAST...WITH LOWS IN THE LOW/MID 70S INLAND TO UPR
70S COAST.
MONDAY...SIMILAR SCENARIO TO THE WEEKEND WITH BROAD TROUGHING AND
WASHED OUT FRONTAL BOUNDARY NEAR THE AREA. BEST SHOWER CHANCES
WILL AGAIN BE NEAR OR JUST OFFSHORE EARLY MONDAY...THEN SEA BREEZE
CONVERGENCE DURING THE AFTERNOON MAY PROMOTE SCT/ISO THUNDERSTORMS
FOR THE SECOND HALF OF THE DAY INLAND. STILL HOT AND MUGGY WITH
HIGHS IN THE LOW 90S INLAND TO 80S COAST.
TUESDAY THROUGH THURSDAY...WARMING TEMPS AS THICKNESSES AND TEMPS
BUILD WITH HIGHS CLIMBING INTO THE MID 90S (80S COAST). SOME MODEL
DIFFERENCES CONTINUE MID WEEK AS 31/00Z GFS CONTINUES TROUGHING
ALONG THE EAST COAST AND PUSHES A FRONT THROUGH THE AREA LATE
WED/THU WITH A WAVE DEVELOPING ALONG IT... WHILE THE ECMWF HAS
BERMUDA HIGH AS MAIN FEATURE AND THERMAL TROUGHING INLAND. WILL
TREND WITH WPC/ECMWF AND PREVIOUS FORECAST WITH HIGH OFFSHORE AND
PRED S/SW FLOW ACROSS THE AREA. WILL CONTINUE SC POPS...THINKING
PRIMARILY DIURNALLY DRIVEN AT THIS TIME AND MAINLY AWAY FROM THE
COAST.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM /THROUGH 12Z SATURDAY/...
AS OF 3 AM FRI...FOG/LOW CLOUD DEVELOPMENT WITH MVFR/IFR
CONDITIONS PSBLE INTO THE EARLY MORN HOURS IN ADVANCE OF THE
FRONT. FRONT WILL HANG UP ALONG THE COAST TODAY WITH SUB VFR
CONDITIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS...MAINLY IN THE
AFTERNOON FOR SOUTHERN AREAS POSSIBLY AFFECTING OAJ AND EWN. WILL
HAVE VCTS FOR THE AFTN AFT 18Z AND VCSH AFT 00Z TNGT FOR THESE TAF
SITES.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...PRED VFR CONDITIONS EXPECTED THROUGH THE
PERIOD. A FRONT WILL STALL NEAR THE COAST OR JUST OFFSHORE THROUGH
THE WEEKEND. ISOLATED TO SCT SHOWERS/TSTMS SAT THROUGH EARLY NEXT
WEEK...WITH BEST CHANCES AT EWN/OAJ. PATCHY FOG/STRATUS POSSIBLE
EACH NIGHT WITH LIGHT WINDS ESP FOR AREAS THAT RECEIVE RAINFALL.
&&
.MARINE...
SHORT TERM /TODAY AND TONIGHT/...
AS OF 1240 PM FRIDAY...STILL GENERALLY NORTHERLY WINDS OVER THE
COASTAL WATERS AND SOUNDS...ALTHOUGH SEEING WINDS VEER TO MORE
SOUTHEAST OVER THE FAR SOUTHERN WATERS. SPEEDS REMAIN LESS THAN
15 KNOTS WITH SEAS OF 3 TO 4 FEET. WILL SEE SOUTHWEST WINDS
DEVELOP WITH A FAIRLY PRONOUNCED SEA BREEZE THIS AFTERNOON OVER
SOUTHERN SECTIONS...WITH LIGHT NORTH WINDS CONTINUING NORTH OF
OCRACOKE. WINDS GRADUALLY BECOME SE TO S TONIGHT 10 KT OR LESS.
WINDS BECOME SW THROUGHOUT TOWARD SAT MORN HIGHEST SRN COASTAL
WATERS. SEAS WILL RANGE 2-4 FT TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 330 AM FRI...THE COLD FRONT WILL WASH OUT BY SAT WITH
SOUTHERLY FLOW ONCE AGAIN DEVELOPING. GRADIENT TIGHTENS THROUGH
THE DAY SAT WITH INCREASING SSW WINDS 10-15KT CONT INTO SUN. A
PERIOD OF MARGINAL SCA CONDITIONS LIKELY TO DEVELOP SUN
NIGHT...MAINLY SOUTH OF OREGON INLET...WITH WINDS INCREASING TO
15-25KT AND SEAS BUILDING TO 4-7FT. GUSTY SW WINDS EXPECTED TO
CONTINUE INTO TUE...WITH LINGERING 6FT SEAS POSSIBLE INTO TUE
NIGHT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JAC
NEAR TERM...CTC
SHORT TERM...JAC
LONG TERM...CQD/TL
AVIATION...CTC/TL
MARINE...CTC/TL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
911 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 853 PM CDT SAT AUG 1 2015
CONVECTION THREAT HAS ENDED OVER SOUTHEAST NORTH DAKOTA. FOCUS NOW
SHIFTS TO THE NORTH. ISOLATED CONVECTION OVER THE PAST HOUR OR SO
OVER SOUTHERN MANITOBA/SASKATCHEWAN IS BEGINNING TO PUSH INTO
NORTHERN NORTH DAKOTA. AN ISOLATED THUNDERSTORM DEVELOPED OVER
BOTTINEAU COUNTY OVER THE PAST HOUR. ML CAPES AROUND 1000-1500
J/KG WITH 50-60 KNOTS OF BULK SHEAR REMAIN OVER THE FAR NORTH
CENTRAL INTO THE TURTLE MOUNTAINS AND A FEW MORE STORMS CAN NOT BE
RULED OUT OVER THE NEXT FEW HOURS. THE THREAT FOR SEVERE WEATHER
WILL BE MINIMAL...AND WILL SHIFT FARTHER EAST AS THE EVENING
PROGRESSES. THIS IS CURRENTLY COVERED IN THE GOING FORECAST.
WE DID BUMP UP WINDS OVER THE WEST AND CENTRAL THIS EVENING
A NICE FALL-RISE PRESSURE BUBBLE WAS NOTED OVER THE NORTHWEST
ASSOCIATED WITH THE SURFACE LOW OVER NORTHWEST NORTH DAKOTA. SOME
40 MPH WIND GUSTS WERE REPORTED OVER THE FAR NORTHWEST WITH THE 8
PM OBSERVATIONS. THE COUPLET WILL TRACK SOUTHEAST ACROSS THE
FORECAST AREA TONIGHT. BUT AS WINDS DECOUPLE THIS EVENING WITH THE
SETTING SUN...THE STRONGER GUST POTENTIAL WILL ALSO SUBSIDE.
UPDATE ISSUED AT 543 PM CDT SAT AUG 1 2015
UNSTABLE AIRMASS REMAINS OVER SOUTHEAST NORTH DAKOTA.
HOWEVER...THERE HAS BEEN ENOUGH CIN TO PRECLUDE THUNDERSTORM
DEVELOPMENT FROM CU FIELD THAT DEVELOPED EARLIER THIS AFTERNOON.
CAPE REMAINS HIGH BUT SHEAR IS DECREASING. WILL KEEP A MENTION OF
THUNDER THROUGH 7 PM AS A FEW CU REMAIN OVER CENTRAL AND EASTERN
PORTIONS OF DICKEY/LAMOURE COUNTIES.
TO THE NORTHWEST...A LINE OF CU HAS DEVELOPED ALONG THE COLD FRONT
MOVING INTO NORTHWEST NORTH DAKOTA. SUFFICIENT BULK SHEAR ALONG
THE INTERNATIONAL BORDER BUT DEEP MOISTURE IS LACKING...ESPECIALLY
RIGHT ALONG AND BEHIND THE FRONT WITH MUCH DRIED DEWPOINTS OVER
THE FAR NORTHWEST AND INTO NORTHEAST NORTH DAKOTA. COULD STILL BE
SOME SHOWER/THUNDERSTORM ACTIVITY HERE LATER THIS EVENING AS THE
FRONT MOVES INTO CENTRAL AND EASTERN NORTH DAKOTA. THIS IS COVERED
IN THE CURRENT FORECAST WITH A MENTION OF SHOWERS ACROSS THE FAR
NORTH CENTRAL...AND INTO THE TURTLE MOUNTAINS AREA THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
SEVERE CONVECTIVE POTENTIAL ACROSS THE JAMES RIVER VALLEY THIS
AFTERNOON HIGHLIGHTS THE SHORT TERM FORECAST.
VISIBLE SATELLITE IMAGERY THROUGH 1920 UTC CONTINUES TO DEPICT A
DEVELOPING CUMULUS FIELD BETWEEN JAMESTOWN...STEELE AND EDGELEY.
THE 13-18 UTC HRRR ITERATIONS HAVE ALL DEPICTED CONVECTIVE
INITIATION FOR THIS AREA BY 21 UTC IN AN ENVIRONMENT CHARACTERIZED
BY ML CAPE AROUND 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40
KTS. WITH A SHORTWAVE EVIDENT JUST UPSTREAM ON WATER
VAPOR...CONVECTIVE POTENTIAL IS INCREASING ALONG WITH THE THREAT
FOR LARGE HAIL AND DAMAGING WINDS IN AN ENVIRONMENT SUPPORTIVE OF
SUPERCELLS...AND HAVE THUS ADDED SEVERE WORDING TO THE JAMES RIVER
VALLEY FOR THIS AFTERNOON. EXPECT THE THREAT TO QUICKLY EXIT INTO
THE GRAND FORKS CWA BY 00 UTC.
LATER THIS EVENING A COLD FRONT WILL PROPAGATE FROM NORTHWEST TO
SOUTHEAST ACROSS NORTH DAKOTA...YIELDING A COOLER BUT STILL
SEASONABLE SUNDAY FOR EARLY AUGUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CDT SAT AUG 1 2015
NORTHWEST FLOW ALOFT THROUGH MONDAY NIGHT. DRY CONDITIONS
EXPECTED WITH SURFACE HIGH PRESSURE FIRMLY IN PLACE ACROSS THE
DAKOTAS. DEEP UPPER LOW MOVING SOUTH INTO THE GREAT LAKES REGION
SUNDAY WILL PUSH A BACK DOOR COLD FRONT INTO THE NORTHERN PLAINS
AND KEEP TEMPERATURES RELATIVELY COOL IN THE 70S TO LOW 80S MONDAY
AND TUESDAY.
A MORE ACTIVE PATTERN MATERIALIZES MID TO LATE NEXT WEEK WHEN OUR
FLOW TRANSITIONS TO MORE ZONAL ALLOWING SEVERAL EMBEDDED WAVES TO
MOVE THROUGH THE REGION. BEST THUNDERSTORM CHANCES WILL BE
CONFINED TO THE SOUTH AND WEST INITIALLY...UNTIL LATER IN THE
WEEK WHEN A CLOSED MID LEVEL CROSSES THE ALBERTA ROCKIES AND MOVES
INTO NORTH DAKOTA FRIDAY. TEMPERATURES DO NOT RECOVER MUCH FROM
EARLY IN THE WEEK...AND LOOK TO REMAIN BELOW AVERAGE FOR EARLY
AUGUST WED-FRI (70S TO LOW 80S).
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 853 PM CDT SAT AUG 1 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. LIGHT
WINDS WILL BECOME SOUTHERLY OR SOUTHWESTERLY AHEAD OF A COLD
FRONT THAT IS HAS MOVED THROUGH KISN...AND EXPECTED THROUGH KMOT
AND KDIK AROUND 03-04Z SATURDAY EVENING...REACHING KJMS AROUND
09Z. DID BUMP UP WINDS FOR A BRIEF PERIOD DIRECTLY BEHIND THE
FRONT THIS EVENING. ESPECIALLY AT KISN...KMOT AND KDIK. EXPECT A
NORTH TO NORTHWEST FLOW ON SUNDAY AT ALL TAF SITES BEHIND THE COLD
FRONT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...AYD
LONG TERM...NH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
906 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 905 PM CDT SAT AUG 1 2015
QUICK UPDATE... WATCH NUMBER 460 IS CANCELLED FOR ALL AREAS NOW.
UPDATE ISSUED AT 832 PM CDT SAT AUG 1 2015
HAVE CANCELLED SEVERE THUNDERSTORM WATCH 460 FOR ALL FGF COUNTIES
EXCEPT GRANT COUNTY IN WEST CENTRAL MN. THE WATCH REMAINS IN
EFFECT UNTIL MIDNIGHT THO GRANT COUNTY WILL LIKELY BE PULLED OUT
BEFORE THEN. MEANWHILE... STORMS ARE FIRING ACROSS SOUTHERN
MANITOBA AHEAD OF A FRONTAL BOUNDARY JUST BEGINNING TO DROP
SOUTHWARD INTO THE US. HAVE BUMPED UP POPS JUST A BIT ACROSS THE
NORTHERN COUNTIES FOR THE EVENING AND OVERNIGHT PERIOD. RISK FOR
SEVERE WEATHER IS LOW DUE TO REDUCED CAPE... THOUGH SOME STRONG
TSTM OUTFLOW IS POSSIBLE WITH THESE STORMS... AS 0-6KM SHEAR
APPROACHES 50KTS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
TWO SEPARATE SHORTWAVES WILL AFFECT THE REGION THIS
EVENING/OVERNIGHT.
THE FIRST WAVE WILL BRING A SEVERE THREAT TO A PORTION OF SE ND
AND WC MN. CURRENT SFC ANALYSIS INDICATES A WEAK SFC LOW ACROSS
SOUTH-CENTRAL NORTH DAKOTA...WITH A WARM FRONTAL FEATURE
EXTENDING TO THE SOUTHEAST. DEWPOINT VALUES ALONG THESE FEATURES
HAVE POOLED INTO THE MID-UPPER 60S...LEADING TO MLCAPE 3000-3500
J/KG. AS THIS SYSTEM EVOLVES AND PROPAGATES TOWARD THE
FA...ANTICIPATE THUNDERSTORM DEVELOPMENT ACROSS THE FAR SOUTHERN
FA. 0-6KM BULK SHEAR 35-40 KNTS COMBINED WITH THE STRONG
INSTABILITY WILL LEAD TO SEVERE STORMS...ALTHOUGH COVERAGE SHOULD
REMAIN ISOLATED GIVEN CONVECTIVE TEMPS NEAR 90F (SOME CAPPING
ISSUES). THIS ACTIVITY WILL MOVE OUT OF THE REGION BY EARLY
EVENING. DID ADD T+ (SEVERE STORMS POSSIBLE) ACROSS FAR SE ND
WHERE CONFIDENCE IS HIGHER IN THUNDER DEVELOPMENT (LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED...AND THE HRRR HAS CONSISTENTLY
INDICATED DEVELOPMENT FROM RUN TO RUN).
NEXT UP WILL BE THE NORTHERN FA THIS EVENING INTO THE OVERNIGHT
HOURS...AS A STRONGER UPPER WAVE BRINGS A COLD FRONT THROUGH THE
REGION. THIS ACTIVITY WILL ENCOUNTER WEAK INSTABILITY (MUCAPE
500-1000 J/KG) BUT VERY STRONG DEEP LAYER SHEAR (60+
KNOTS)...ALONG WITH MID-LEVEL WINDS IN EXCESS OF 50 KNTS. THE 18Z
HRRR IS INDICATING A SMALL BOW ECHO WITH SFC WIND GUSTS 50-55
KNOTS 02Z-05Z. OF COURSE THAT IS JUST ONE POSSIBLE SOLUTION...BUT
IT DOES SPEAK TO THE POTENTIAL OF WHAT COULD OCCUR ACROSS THE
NORTHERN FA THIS EVENING AND OVERNIGHT. THIS FORCING MAY ALSO
INTERACT WITH INCREASING INSTABILITY FROM THE SOUTH AFTER
MIDNIGHT...WHICH MAY BE ENOUGH FOR A FEW STRONGER STORMS INTO THE
OVERNIGHT HOURS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
THIS PERIOD STARTS OFF WITH A BROAD UPPER LEVEL LOW OVER ONTARIO
AND COOL HIGH PRESSURE IN PLACE AT THE SURFACE OVER SASKATCHEWAN
AND THE DAKOTAS. THE WEATHER WILL BE DRY AND SLIGHTLY COOLER THAN
AVERAGE FOR THE START OF THE WEEK. HOWEVER...A WEAK UPPER LEVEL
WAVE WILL MOVE EAST IN THE WEAK UPPER FLOW...UNDERCUTTING A
WESTERN U.S. RIDGE BY MID WEEK. THE MODELS HAVE HAD A HARD TIME
WITH THIS SYSTEM. PREVIOUS RUNS HAD MORE INSTABILITY AND MUCH MORE
OF A PRECIPITATION SIGNAL AREA-WIDE. THE LATEST GFS HAS BEST
LIFT/INSTABILITY IN THE FAR SOUTH ON WEDNESDAY NIGHT.
SO...CONFIDENCE IS DECREASING IN WEDNESDAYS SYSTEM. ANOTHER WEAK
WAVE WILL AFFECT PRIMARILY THE SOUTH ON THURSDAY...BUT
AGAIN...THIS ONE HAS TRENDED SOUTHWARD. HOWEVER...FRIDAYS SYSTEM
LOOKS TO BE THE WAVE THAT HAS THE MOST AGREEMENT REGARDING TRACK
AND COULD BRING WIDESPREAD PRECIP TO THE AREA. WITH PLENTY OF
UNCERTAINTY ON THESE WAVES...TOO EARLY TO TALK ABOUT SEVERE
POTENTIAL. PRECIPITATION CHANCES EXIST INTO SATURDAY AS WELL AND
WILL DEPEND ON SPEED OF UPPER LOW. TEMPERATURES LOOK TO BE COOL
FOR MUCH OF THIS PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
UPDATED AT 835 PM CDT SAT AUG 1 2015
GENERALLY FAIR SKIES THROUGH THE EVENING AND OVERNIGHT ACROSS
THESOUTHERN FA AS SEVERE THUNDERSTORM THREAT THERE IS NOW MINIMAL.
MEANWHILE... A WEAK COLD FRONT WILL DROP FROM SOUTHERN SASK AND
MANITOBA ACROSS THE NORTHERN HALF OF THE FA... ALG AND NORTH OF A
CANDO TO GRAND FORKS AND BEMIDJI LINE... WITH SCATTERED SHOWERS
AND AN ISOLATED MVFR CIG AND VSBY IN STRONG THUNDERSTORMS IN THE
MIX. SCATTERED SHOWERS SHOULD PERSIST INTO THE MORNING HOURS
ACROSS NORTHERN MN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GUST
SHORT TERM...TG
LONG TERM...KNUTSVIG
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
839 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 832 PM CDT SAT AUG 1 2015
HAVE CANCELLED SEVERE THUNDERSTORM WATCH 460 FOR ALL FGF COUNTIES
EXCEPT GRANT COUNTY IN WEST CENTRAL MN. THE WATCH REMAINS IN
EFFECT UNTIL MIDNIGHT THO GRANT COUNTY WILL LIKELY BE PULLED OUT
BEFORE THEN. MEANWHILE... STORMS ARE FIRING ACROSS SOUTHERN
MANITOBA AHEAD OF A FRONTAL BOUNDARY JUST BEGINNING TO DROP
SOUTHWARD INTO THE US. HAVE BUMPED UP POPS JUST A BIT ACROSS THE
NORTHERN COUNTIES FOR THE EVENING AND OVERNIGHT PERIOD. RISK FOR
SEVERE WEATHER IS LOW DUE TO REDUCED CAPE... THOUGH SOME STRONG
TSTM OUTFLOW IS POSSIBLE WITH THESE STORMS... AS 0-6KM SHEAR
APPROACHES 50KTS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
TWO SEPARATE SHORTWAVES WILL AFFECT THE REGION THIS
EVENING/OVERNIGHT.
THE FIRST WAVE WILL BRING A SEVERE THREAT TO A PORTION OF SE ND
AND WC MN. CURRENT SFC ANALYSIS INDICATES A WEAK SFC LOW ACROSS
SOUTH-CENTRAL NORTH DAKOTA...WITH A WARM FRONTAL FEATURE
EXTENDING TO THE SOUTHEAST. DEWPOINT VALUES ALONG THESE FEATURES
HAVE POOLED INTO THE MID-UPPER 60S...LEADING TO MLCAPE 3000-3500
J/KG. AS THIS SYSTEM EVOLVES AND PROPAGATES TOWARD THE
FA...ANTICIPATE THUNDERSTORM DEVELOPMENT ACROSS THE FAR SOUTHERN
FA. 0-6KM BULK SHEAR 35-40 KNTS COMBINED WITH THE STRONG
INSTABILITY WILL LEAD TO SEVERE STORMS...ALTHOUGH COVERAGE SHOULD
REMAIN ISOLATED GIVEN CONVECTIVE TEMPS NEAR 90F (SOME CAPPING
ISSUES). THIS ACTIVITY WILL MOVE OUT OF THE REGION BY EARLY
EVENING. DID ADD T+ (SEVERE STORMS POSSIBLE) ACROSS FAR SE ND
WHERE CONFIDENCE IS HIGHER IN THUNDER DEVELOPMENT (LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED...AND THE HRRR HAS CONSISTENTLY
INDICATED DEVELOPMENT FROM RUN TO RUN).
NEXT UP WILL BE THE NORTHERN FA THIS EVENING INTO THE OVERNIGHT
HOURS...AS A STRONGER UPPER WAVE BRINGS A COLD FRONT THROUGH THE
REGION. THIS ACTIVITY WILL ENCOUNTER WEAK INSTABILITY (MUCAPE
500-1000 J/KG) BUT VERY STRONG DEEP LAYER SHEAR (60+
KNOTS)...ALONG WITH MID-LEVEL WINDS IN EXCESS OF 50 KNTS. THE 18Z
HRRR IS INDICATING A SMALL BOW ECHO WITH SFC WIND GUSTS 50-55
KNOTS 02Z-05Z. OF COURSE THAT IS JUST ONE POSSIBLE SOLUTION...BUT
IT DOES SPEAK TO THE POTENTIAL OF WHAT COULD OCCUR ACROSS THE
NORTHERN FA THIS EVENING AND OVERNIGHT. THIS FORCING MAY ALSO
INTERACT WITH INCREASING INSTABILITY FROM THE SOUTH AFTER
MIDNIGHT...WHICH MAY BE ENOUGH FOR A FEW STRONGER STORMS INTO THE
OVERNIGHT HOURS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
THIS PERIOD STARTS OFF WITH A BROAD UPPER LEVEL LOW OVER ONTARIO
AND COOL HIGH PRESSURE IN PLACE AT THE SURFACE OVER SASKATCHEWAN
AND THE DAKOTAS. THE WEATHER WILL BE DRY AND SLIGHTLY COOLER THAN
AVERAGE FOR THE START OF THE WEEK. HOWEVER...A WEAK UPPER LEVEL
WAVE WILL MOVE EAST IN THE WEAK UPPER FLOW...UNDERCUTTING A
WESTERN U.S. RIDGE BY MID WEEK. THE MODELS HAVE HAD A HARD TIME
WITH THIS SYSTEM. PREVIOUS RUNS HAD MORE INSTABILITY AND MUCH MORE
OF A PRECIPITATION SIGNAL AREA-WIDE. THE LATEST GFS HAS BEST
LIFT/INSTABILITY IN THE FAR SOUTH ON WEDNESDAY NIGHT.
SO...CONFIDENCE IS DECREASING IN WEDNESDAYS SYSTEM. ANOTHER WEAK
WAVE WILL AFFECT PRIMARILY THE SOUTH ON THURSDAY...BUT
AGAIN...THIS ONE HAS TRENDED SOUTHWARD. HOWEVER...FRIDAYS SYSTEM
LOOKS TO BE THE WAVE THAT HAS THE MOST AGREEMENT REGARDING TRACK
AND COULD BRING WIDESPREAD PRECIP TO THE AREA. WITH PLENTY OF
UNCERTAINTY ON THESE WAVES...TOO EARLY TO TALK ABOUT SEVERE
POTENTIAL. PRECIPITATION CHANCES EXIST INTO SATURDAY AS WELL AND
WILL DEPEND ON SPEED OF UPPER LOW. TEMPERATURES LOOK TO BE COOL
FOR MUCH OF THIS PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
UPDATED AT 835 PM CDT SAT AUG 1 2015
GENERALLY FAIR SKIES THROUGH THE EVENING AND OVERNIGHT ACROSS
THESOUTHERN FA AS SEVERE THUNDERSTORM THREAT THERE IS NOW MINIMAL.
MEANWHILE... A WEAK COLD FRONT WILL DROP FROM SOUTHERN SASK AND
MANITOBA ACROSS THE NORTHERN HALF OF THE FA... ALG AND NORTH OF A
CANDO TO GRAND FORKS AND BEMIDJI LINE... WITH SCATTERED SHOWERS
AND AN ISOLATED MVFR CIG AND VSBY IN STRONG THUNDERSTORMS IN THE
MIX. SCATTERED SHOWERS SHOULD PERSIST INTO THE MORNING HOURS
ACROSS NORTHERN MN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GUST
SHORT TERM...TG
LONG TERM...KNUTSVIG
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
636 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 629 PM CDT SAT AUG 1 2015
SEVERE THUNDERSTORM WATCH 460 HASD BEEN ISSUED FOR EXTREME
SOUTHEASTERN ND AND ADJACENT COUNTIES NORTHEASTERN SD AND WEST
CENTRAL MN UNTIL MIDNIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
TWO SEPARATE SHORTWAVES WILL AFFECT THE REGION THIS
EVENING/OVERNIGHT.
THE FIRST WAVE WILL BRING A SEVERE THREAT TO A PORTION OF SE ND
AND WC MN. CURRENT SFC ANALYSIS INDICATES A WEAK SFC LOW ACROSS
SOUTH-CENTRAL NORTH DAKOTA...WITH A WARM FRONTAL FEATURE
EXTENDING TO THE SOUTHEAST. DEWPOINT VALUES ALONG THESE FEATURES
HAVE POOLED INTO THE MID-UPPER 60S...LEADING TO MLCAPE 3000-3500
J/KG. AS THIS SYSTEM EVOLVES AND PROPAGATES TOWARD THE
FA...ANTICIPATE THUNDERSTORM DEVELOPMENT ACROSS THE FAR SOUTHERN
FA. 0-6KM BULK SHEAR 35-40 KNTS COMBINED WITH THE STRONG
INSTABILITY WILL LEAD TO SEVERE STORMS...ALTHOUGH COVERAGE SHOULD
REMAIN ISOLATED GIVEN CONVECTIVE TEMPS NEAR 90F (SOME CAPPING
ISSUES). THIS ACTIVITY WILL MOVE OUT OF THE REGION BY EARLY
EVENING. DID ADD T+ (SEVERE STORMS POSSIBLE) ACROSS FAR SE ND
WHERE CONFIDENCE IS HIGHER IN THUNDER DEVELOPMENT (LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED...AND THE HRRR HAS CONSISTENTLY
INDICATED DEVELOPMENT FROM RUN TO RUN).
NEXT UP WILL BE THE NORTHERN FA THIS EVENING INTO THE OVERNIGHT
HOURS...AS A STRONGER UPPER WAVE BRINGS A COLD FRONT THROUGH THE
REGION. THIS ACTIVITY WILL ENCOUNTER WEAK INSTABILITY (MUCAPE
500-1000 J/KG) BUT VERY STRONG DEEP LAYER SHEAR (60+
KNOTS)...ALONG WITH MID-LEVEL WINDS IN EXCESS OF 50 KNTS. THE 18Z
HRRR IS INDICATING A SMALL BOW ECHO WITH SFC WIND GUSTS 50-55
KNOTS 02Z-05Z. OF COURSE THAT IS JUST ONE POSSIBLE SOLUTION...BUT
IT DOES SPEAK TO THE POTENTIAL OF WHAT COULD OCCUR ACROSS THE
NORTHERN FA THIS EVENING AND OVERNIGHT. THIS FORCING MAY ALSO
INTERACT WITH INCREASING INSTABILITY FROM THE SOUTH AFTER
MIDNIGHT...WHICH MAY BE ENOUGH FOR A FEW STRONGER STORMS INTO THE
OVERNIGHT HOURS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
THIS PERIOD STARTS OFF WITH A BROAD UPPER LEVEL LOW OVER ONTARIO
AND COOL HIGH PRESSURE IN PLACE AT THE SURFACE OVER SASKATCHEWAN
AND THE DAKOTAS. THE WEATHER WILL BE DRY AND SLIGHTLY COOLER THAN
AVERAGE FOR THE START OF THE WEEK. HOWEVER...A WEAK UPPER LEVEL
WAVE WILL MOVE EAST IN THE WEAK UPPER FLOW...UNDERCUTTING A
WESTERN U.S. RIDGE BY MID WEEK. THE MODELS HAVE HAD A HARD TIME
WITH THIS SYSTEM. PREVIOUS RUNS HAD MORE INSTABILITY AND MUCH MORE
OF A PRECIPITATION SIGNAL AREA-WIDE. THE LATEST GFS HAS BEST
LIFT/INSTABILITY IN THE FAR SOUTH ON WEDNESDAY NIGHT.
SO...CONFIDENCE IS DECREASING IN WEDNESDAYS SYSTEM. ANOTHER WEAK
WAVE WILL AFFECT PRIMARILY THE SOUTH ON THURSDAY...BUT
AGAIN...THIS ONE HAS TRENDED SOUTHWARD. HOWEVER...FRIDAYS SYSTEM
LOOKS TO BE THE WAVE THAT HAS THE MOST AGREEMENT REGARDING TRACK
AND COULD BRING WIDESPREAD PRECIP TO THE AREA. WITH PLENTY OF
UNCERTAINTY ON THESE WAVES...TOO EARLY TO TALK ABOUT SEVERE
POTENTIAL. PRECIPITATION CHANCES EXIST INTO SATURDAY AS WELL AND
WILL DEPEND ON SPEED OF UPPER LOW. TEMPERATURES LOOK TO BE COOL
FOR MUCH OF THIS PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 629 PM CDT SAT AUG 1 2015
GENERALLY FAIR SKIES THROUGH THE EVENING WITH ISOLATED STRONG TO
SEVERE THUNDERSTORMS ALONG THE SOUTH DAKOTA BORDER COUNTIES...
INTO ADJACENT AREAS OF WEST CENTRAL MINNESOTA. THUNDERSTORMS
SHOULD EXIT THAT AREA BY 04Z.
LATER TONIGHT... A WEAK COLD FRONT WILL DROP FROM SOUTHERN SASK
AND MANITOBA ACROSS THE NORTHERN HALF OF THE FA... ALG AND NORTH
OF A CANDO TO GRAND FORKS AND BEMIDJI LINE... WITH SCATTERED
SHOWERS AND AN ISOLATED MVFR CIG AND VSBY IN STRONG THUNDERSTORMS
IN THE MIX. SCTATTERED SHOWERS SHOULD PERSIST INTO TEH MORNING
HOURS ACROSS NORTHERN MN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...SEVERE THUNDERSTORM WATCH 460 UNTIL MIDNIGHT.
MN...SEVERE THUNDERSTORM WATCH 460 UNTIL MIDNIGHT
&&
$$
UPDATE...GUST
SHORT TERM...TG
LONG TERM...KNUTSVIG
AVIATION...GUST
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
937 AM EDT FRI JUL 31 2015
.SYNOPSIS...
HIGH PRESSURE REMAINS OVER THE OHIO VALLEY WITH A TROUGH
OVER EASTERN CANADA. A WEAK FRONT WILL SINK SOUTH ACROSS THE AREA
THIS EVENING. HIGH PRESSURE WILL EXPAND OVER THE LOWER LAKES REGION
ON SATURDAY...SHIFTING TO THE EAST ON SUNDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
LATEST HRRR MODEL APPEARS TO BE BACKING OFF ON CHANCES FOR
PRECIPITATION LATER THIS AFTERNOON. WILL KEEP THE MENTION OF A
SLIGHT CHANCE FOR SHOWERS AND THUNDERSTORMS AS SURFACE TROUGH
SLIPS EAST ACROSS THE REGION. OTHERWISE...NO MAJOR CHANGES TO THIS
UPDATE.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
ALTHOUGH THE FRONT WILL BE EAST OF THE AREA BY SATURDAY
MORNING...A WEAK THERMAL TROUGH IN THE VICINITY OF EASTERN LAKE
ERIE COULD RESULT IN SOME CLOUDS AND MOISTURE LINGERING IN THE NE
COUNTIES. WILL HOLD ONTO A SLIGHT CHANCE POP ON SATURDAY MORNING
IN NW PA...EXPANDING TO NORTHWEST OHIO BY AFTERNOON AHEAD OF
ANOTHER SHORTWAVE. TEMPERATURES ON SATURDAY WILL BE A LITTLE
COOLER IN THE UPPER 70S/LOW 80S.
SURFACE HIGH PRESSURE EXPANDS EASTWARD ON SATURDAY NIGHT AND SUNDAY
AHEAD OF THE NEXT TROUGH TO APPROACH FROM THE NORTHWEST. THIS
FEATURE DEVELOPS AHEAD OF A SLIGHTLY STRONGER UPPER LEVEL WAVE
DROPPING SOUTH ACROSS CANADA. BETTER MOISTURE ADVECTION IS EXPECTED
AHEAD OF THIS NEXT TROUGH WITH CHANCES OF SHOWERS AND THUNDERSTORMS
DEVELOPING SUNDAY AFTERNOON IN THE NORTH...AND EXPANDING TO ALL
AREAS FOR SUNDAY NIGHT AND MONDAY. SEASONAL TEMPERATURES WILL
CONTINUE.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
THE MODELS LOOK SIMILAR THROUGH MID WEEK WITH THE FRONT
INITIALLY STALLING SOMEWHERE NEAR THE OHIO VALLEY. THIS MAKES FOR A
CHANCE FOR SOME OVER RUNNING SHOWERS...MAINLY ACROSS THE SOUTHERN
PORTION OF THE FORECAST AREA. STILL NOT A LOT OF CONFIDENCE ON THE
THREAT OF RAIN BUT WILL INCLUDE A SMALL CHANCE IN THE SOUTH. 850 MB
TEMPERATURES MAY GET COLD ENOUGH FOR LAKE EFFECT RAIN SHOWERS
ALTHOUGH THERE MAY BE ENOUGH SUBSIDENCE AND SHEAR THAT NOTHING
MATERIALIZES. IT IS WORTH A MENTION BY TUESDAY NIGHT INTO
WEDNESDAY.
THE MODELS REMAIN FAR APART BY NEXT THURSDAY WITH THE GFS
CONTINUING TO DRIVE THE FRONT WELL SOUTH OF THE AREA AND THE ECMWF
DEVELOPING ANOTHER OVER RUNNING WAVE THAT COULD AT LEAST CATCH THE
SOUTHERN PART OF THE FORECAST AREA. WILL CONTINUE TO FAVOR THE DRY
FORECAST...ONE WOULD EXPECT THE SURFACE HIGH TO BUILD SOUTH AT
SOME POINT GIVEN THE DEEPENING TROUGH ALOFT.
SHAVED OFF A DEGREE OR TWO ON FORECAST HIGH TEMPERATURES MID WEEK
GIVEN THE THREAT FOR CLOUDS AND SHOWERS AND THE COOL FLOW. TEMPS
COULD BE COOLER THAN FORECAST...ESPECIALLY IF IT WAS TO BE CLOUDY
AND RAINY BUT WITH THE DAYS SO LONG AND WARM IN EARLY AUGUST WILL
STAY WITHIN 10 DEGREES OF NORMAL FOR NOW.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A CHUNK OF HIGH PRESSURE AT THE SURFACE WAS OVER THE OHIO VALLEY
SLIDING EAST. A WEAK COLD FRONT/TROUGH OVER THE NORTHERN GREAT
LAKES WILL DROP ACROSS THE AREA LATE THIS AFTERNOON AND EVENING.
WEST WINDS WILL GET A BIT GUSTY THIS AFTERNOON AHEAD OF THE
TROUGH. MOISTURE IS VERY LIMITED BUT THERE SHOULD BE SOME CAPE
DEVELOP IN THE HEATING OF THE DAY. AN INCREASE IN SHEAR IS
PROGGED. A FEW THUNDERSTORMS COULD POP UP. COVERAGE WILL LIKELY BE
SMALL BUT THE THREAT IS MENTIONED IN THE CURRENT TAF FORECASTS AS
"VICINITY" AND WILL CONTINUE WITH THAT FORECAST LATE THIS
AFTERNOON INTO TONIGHT.
OUTLOOK...NON VFR POSSIBLE SUNDAY AFTERNOON AND MONDAY IN
SHRA/TSRA.
&&
.MARINE...
WITH A RELATIVELY FAST FLOW ALOFT...EACH WEAK FRONT/TROUGH WILL
PRODUCE THE POSSIBILITY OF SMALL CRAFT ADVISORY CONDITIONS ON LAKE
ERIE...MAINLY THE EAST HALF OF THE LAKE SINCE THE FLOW IS WEST
SOUTHWEST. A WEAK TROUGH IS EXPECTED THIS EVENING AND WILL POST A
SMALL CRAFT ADVISORY FOR THE ERIE COUNTY PA LAKESHORE FROM EARLY
AFTERNOON INTO TONIGHT. THE MAJORITY OF THE WIND WILL BE OVER THE
EAST THIRD OF THE LAKE BUT 4 FOOT WAVES ARE CERTAINLY POSSIBLE
AT ERIE PA LATER TODAY INTO TONIGHT.
THE NEXT WEAK FRONT/TROUGH WILL BE LATER SUNDAY WITH A STRONGER COLD
FRONT ON MONDAY. BOTH OF THOSE SYSTEMS MAY WELL REQUIRE A SMALL
CRAFT ADVISORY...ESPECIALLY FOR THE EAST LAKESHORE.
HIGH PRESSURE WILL BUILD ACROSS THE NORTHERN LAKES NEXT WEEK AND THE
FLOW WILL LIKELY VEER MORE FROM THE NORTH BY MID WEEK.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...BEACH HAZARDS STATEMENT FROM 2 PM EDT THIS AFTERNOON THROUGH
LATE TONIGHT FOR PAZ001.
MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 2 AM EDT
SATURDAY FOR LEZ149.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS NORMAN OK
1220 PM CDT FRI JUL 31 2015
.UPDATE...
UPDATE TO PRECIP/WX...
&&
.DISCUSSION...
SCATTERED SHOWERS AND ISOLATED THUNDER ACROSS CENTRAL OK CONTINUES
TO WEAKEN... BUT REMAIN PERSISTENT. MUCH... IF NOT ALL OF THIS
ACTIVITY IS LIKELY TIED TO MODEST LOW LEVEL ASCENT ASSOCIATED WITH
A WEAK 850MB TROUGH AND VARIOUS WEAKENING OUTFLOW BOUNDARIES
ASSOCIATED WITH EARLIER CONVECTION. FOR THIS AFTN... PRIMARY FOCUS
IS ON CONTINUOUS ACTIVITY ACROSS THE TX PH... AS NEW UPDRAFTS HAVE
STARTED TO DEVELOP ON OR JUST WEST OF THE OK/TXPH BORDER.
DIFFICULT TO PINPOINT EXACT FORCING FOR ASCENT... BUT IT APPEARS
TIED TO SFC/LL CONVERGENCE. LATEST HRRR RUN HAS MOST OF THIS
ACTIVITY DISSIPATING THROUGH EARLY/MID AFTN AS UPPER LVL SUPPORT
FROM THE WEAK H500 SHORT WAVE EMBEDDED IN THE LARGER RIDGE EXITS
TO THE EAST. INITIAL STORMS IN WRN OK WILL RESIDE IN A REGION OF
MODEST INSTABILITY... SUPPORTIVE OF GUSTY WINDS AND LOCALLY HEAVY
RAINFALL. NOT EXPECTING ANY ORGANIZED SEVERE STORMS THROUGH THIS
AFTN.
JTK
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT FRI JUL 31 2015/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 71 91 71 91 / 10 10 20 10
HOBART OK 71 89 70 93 / 30 30 20 10
WICHITA FALLS TX 74 96 73 95 / 20 20 20 10
GAGE OK 68 86 67 92 / 20 20 30 10
PONCA CITY OK 71 91 72 92 / 10 10 20 10
DURANT OK 73 97 73 95 / 10 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS NORMAN OK
1213 PM CDT FRI JUL 31 2015
.AVIATION...
ISOLATED TO SCATTERED SHOWERS AND STORMS WILL CONTINUE THROUGH
THE AFTERNOON AND OVERNIGHT...BUT DID NOT MENTION IN TAFS BECAUSE
CONFIDENCE IN STORMS IMPACTING ANY PARTICULAR LOCATION IS LOW.
EXPECT MID CLOUDINESS TO PERSIST...THOUGH CONDITIONS SHOULD
REMAIN GENERALLY VFR. LIGHT EAST WINDS WILL GRADUALLY SHIFT TO
THE SOUTH OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 614 AM CDT FRI JUL 31 2015/
DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 30 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 30 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
04/14/14
AREA FORECAST DISCUSSION
NWS NORMAN OK
614 AM CDT FRI JUL 31 2015
.DISCUSSION...
AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW.
&&
.AVIATION...
OVERALL...VFR CONDITIONS ARE EXPECTED.
SOME MVFR...PERHAPS IFR...CONDITIONS MAY AFFECT KWWR AND KGAG
THROUGH 16Z.
ISO-SCT SHRA/TSRA WILL BE OVER THE AREA FOR THE NEXT 24 HOURS.
ONLY INCLUDED VCTS AND VCSH NEAR KOKC AND KOUN THROUGH 16-17Z
WHERE CONFIDENCE OF OCCURRENCE IS HIGHER. PINPOINTING WHERE AND
WHEN SHRA/TSRA OCCUR REMAINS VERY TRICKY AND CHALLENGING...SO DID
NOT MENTION IN MANY TAFS AS COVERAGE SHOULD BE LOW. BRIEF MVFR OR
LOWER CONDITIONS AND VARIABLE GUSTY WINDS ARE POSSIBLE WITH
SHRA/TSRA.
MBS
&&
.PREV DISCUSSION... /ISSUED 309 AM CDT FRI JUL 31 2015/
DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 20 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 20 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/17/17
AREA FORECAST DISCUSSION
NWS NORMAN OK
309 AM CDT FRI JUL 31 2015
.DISCUSSION...
THE MAIN CONCERN IS DETERMINING RAIN CHANCES OVER THE NEXT
SEVERAL DAYS.
OVERALL...LOWERED RAIN CHANCES OVER THE NEXT SEVERAL DAYS BASED
ON LATEST MODEL GUIDANCE. THE COMBINATION OF WEAK SHEAR AND WEAK
FORCING AS WELL AS DECENT CAPPING SHOULD KEEP RAIN CHANCES ON THE
LOW SIDE IN MOST LOCATIONS.
TODAY WILL NOT BE AS HOT IN MANY LOCATIONS WITH MORE CLOUD
COVER...BUT WILL BE HUMID WITH SURFACE DEWPOINTS MAINLY IN THE
LOWER TO MID 70S. KEPT 20 PERCENT ACROSS THE ENTIRE AREA. ITS
QUITE DIFFICULT TO PINPOINT WHERE AND WHEN STORMS WILL OCCUR
TODAY. LATEST HRRR RUNS SUGGEST A FEW STORMS WILL BE NEAR I-40
THIS MORNING AND MAINLY ACROSS SOUTHERN OKLAHOMA AND NORTH TEXAS
THIS AFTERNOON. COVERAGE SHOULD BE SPARSE WITHOUT A SIGNIFICANT
TRIGGER FOR LIFT. STORMS WILL BE PULSE AND GENERALLY SHORT LIVED IN
NATURE...BUT COULD PRODUCE LOCALLY HEAVY RAINFALL OVER AN INCH IN
A SHORT PERIOD OF TIME. SEVERE POTENTIAL REMAINS LOW TODAY.
INCREASED HIGHS TODAY FROM THE PREVIOUS FORECAST DUE TO LOW
COVERAGE OF STORMS.
TONIGHT THROUGH SUNDAY NIGHT...A FEW STORMS MAY LINGER MAINLY
OVER FAR WESTERN OKLAHOMA AND FAR WESTERN NORTH TEXAS...WHICH MAY
PRODUCE SOME LOCALIZED HEAVY RAINFALL. SEVERE POTENTIAL REMAINS
VERY LOW. OTHERWISE...MAINLY RAINFREE CONDITIONS WILL OCCUR. HIGHS
ON SATURDAY AND SUNDAY SHOULD REMAIN SLIGHTLY BELOW AVERAGE IN
MANY AREAS EXCEPT POSSIBLY FAR SOUTHERN OKLAHOMA AND NORTH TEXAS
WHERE MORE SUN IS FORECAST.
MONDAY THROUGH THURSDAY...GENERALLY TYPICAL SUMMERTIME HEAT IS
FORECAST. LOW CHANCES FOR RAIN AND STORMS MAY OCCUR MAINLY OVER
NORTHERN OKLAHOMA...BUT CONFIDENCE OF RAIN IS DECREASING AS
LATEST MODELS HAVE BEEN TRENDING STRONGER WITH MID/UPPER RIDGING
AND CAPPING OVER THE AREA. THIS WOULD YIELD HIGHER TEMPERATURES
AS WELL. WOULD NOT BE SURPRISED IF HEAT ADVISORIES WERE NECESSARY
SOMETIME DURING THIS TIME FRAME.
MBS
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 91 71 91 71 / 20 10 10 20
HOBART OK 94 71 89 70 / 20 30 30 20
WICHITA FALLS TX 96 74 96 73 / 20 20 20 20
GAGE OK 88 68 86 67 / 20 20 20 30
PONCA CITY OK 91 71 91 72 / 20 10 10 20
DURANT OK 96 73 97 73 / 20 10 10 10
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
84/17
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
143 PM EDT FRI JUL 31 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL BUILD IN BEHIND A DEPARTING COLD FRONT TODAY
AND REMAIN IN PLACE THROUGH THE WEEKEND. LOW LEVEL MOISTURE WILL
GRADUALLY RETURN THROUGH NEXT WEEK AS ANOTHER COLD FRONT APPROACHES
FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM EDT FRIDAY...FORECAST RUNNING PRETTY MUCH ON TRACK
WITH NOT MUCH IN THE WAY OF SENSIBLE WEATHER TO WRITE HOME ABOUT.
DESPITE THE HEAT...A FAIRLY NICE DAY WITH DEWPOINTS LOWER IN THE
WAKE OF THE WEAK FRONTAL PASSAGE. VERY LITTLE CHANGES MADE TO THE
GRIDS THIS MORNING...HAVE UPDATED TEMPS AND DEWPOINTS BASED ON
TRENDS AND IT IS POSSIBLE THAT HIGHS MIGHT BE JUST A TOUCH LOWER
THAN FORECAST BUT WILL CONTINUE TO MONITOR. POPS LOOK GOOD FOR
NOW...SPC DAY1 OUTLOOK DOES INCLUDE EXTREME SOUTHEAST PORTIONS OF
THE CWA IN GENERAL THUNDER BUT LOOKING AT THE HRRR AND OTHER CAMS
SEEMS WE WILL BE PRETTY HARD-PRESSED TO SEE CONVECTION TODAY. CLOUDS
WILL CONTINUE TO SCATTER OUT OVER THE NEXT COUPLE OF HOURS.
1045 UTC UPDATE...SKY COVER WAS UPDATED FORM INFRARED SATELLITE
IMAGERY...RESULTING IN A DECREASE. POPS WERE ADJUSTED DOWN PER
TRENDS.
AT 300 AM EDT FRIDAY...AN UPPER RIDGE WILL SLOWLY RETROGRESS TODAY AND
TONIGHT FROM THE SOUTHERN PLAINS TO THE SOUTHERN ROCKIES...WHILE AN
UPPER TROUGH AMPLIFIES OVER THE EASTERN USA. A COLD FRONT WILL MOVE
SLOWLY SOUTH AND OUT OF OUR AREA...STALLING NEAR THE COAST OF THE
CAROLINAS AND GA. MOISTURE ASSOCIATED WITH THIS BOUNDARY APPEARS TO
GENERALLY REMAIN JUST SE OF OUR AREA...OFFERING LITTLE SUPPORT FOR
CONVECTION. TEMPERATURES WILL RUN NEAR NORMAL TODAY AND TONIGHT AS
WEAK COOL ADVECTION IS OFFSET BY LIMITED DOWNSLOPE WARMING FLOW IN
LIGHT NORTHERLY WINDS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 150 AM FRIDAY...QUIET WEATHER EXPECTED THRU THE SHORT RANGE.
AN UPPER TROF REMAINS ACROSS MUCH OF THE ERN CONUS WITH NO
SIGNIFICANT SHORT WAVE ENERGY MOVING THRU THE TROF. AT THE SFC...
DRY HIGH PRESSURE BUILDS IN ACROSS THE AREA SAT AND SUN. GUIDANCE
BLEND SHOWS DEW POINTS MIXING OUT INTO THE 50S ACROSS THE AREA BOTH
DAYS. THIS COMBINED WITH RELATIVELY WARM MID LEVEL AIR WILL LEAD TO
LITTLE TO NO CAPE EACH AFTERNOON...RESULTING IN VERY LOW POTENTIAL
FOR DEEP MOIST CONVECTION. A REMNANT COLD FRONT BOUNDARY WILL BE
CLOSE BUT SOUTH OF THE AREA PROVIDING LITTLE TO NO LOW LEVEL
CONVERGENCE FOR THE AREA. THEREFORE...HAVE GONE WITH A DRY FCST.
EXPECT TEMPS TO BE NEAR TO A LITTLE ABOVE NORMAL THRU THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 255 AM FRIDAY...GUIDANCE IS IN DECENT AGREEMENT THRU THE
PERIOD. EAST COAST TROF FLATTENS THRU THE PERIOD WITH WLY FLOW
DEVELOPING ACROSS THE AREA AS HEIGHTS RISE. THIS ALLOWS A SERIES OF
SHORT WAVES TO MOVE ACROSS OR NEAR THE AREA. THE DRY HIGH PRESSURE
OVER THE AREA SLOWLY MODERATES THEN DISSIPATES AS A COLD FRONT DROPS
SOUTH TOWARD THE AREA. THE COLD FRONT INITIALLY STALLS...THEN MOVES
INTO THE AREA THU AS A LOW PRESSURE AREA TRACKS FROM THE OH VALLEY
OFF THE MID ATLANTIC COAST. THE RESULT IS AN INCREASE IN LOW LEVEL
MOISTURE AND INSTABILITY THRU THE PERIOD. THE BEST FORCING...AND
RESULTANT CONVECTION...WILL BE WED AND THU...WITH A DRY FCST MON AND
ONLY ISOLATED CONVECTION TUE ACROSS THE MTNS. WITH THE RISING
HEIGHTS AND LINGERING HIGH PRESSURE MON AND TUE...TEMPS WILL BE
ABOVE NORMAL. TEMPS SLOWLY FALL WED AND THU...BUT REMAIN ABOVE
NORMAL.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AT KCLT AND ELSEWHERE...VFR...WITH THE POSSIBLE EXCEPTION OF BRIEF
MVFR FOG AT KHKY BETWEEN 06-12Z SATURDAY BUT CHANCE NOT HIGH ENOUGH
TO INCLUDE IN TAF AT THIS TIME. VERY LITTLE MOISTURE TO WORK WITH IN
THE WAKE OF THE FRONT THIS MORNING SO EXPECT AT BEST FEW TO SCT
CLOUDS AROUND 5-6KFT FOR THIS AFTERNOON...WITH POSSIBLY ANOTHER
ROUND SATURDAY AFTERNOON...BUT MOISTURE IS EVEN MORE LIMITED BY THAT
POINT. COULD SEE PASSING CIRRUS OFF AND ON AS WELL. DO NOT EXPECT
ANY CONVECTION THROUGH THE PERIOD AT THE TAF SITES. WINDS SHOULD
REMAIN GENERALLY N TO NE WITH ONLY BRIEF SWINGS TOWARD E...BUT
REMAINING ON THE N SIDE. COULD SEE SOME OFF-AND-ON LOW-END GUSTS
THROUGH THIS AFTERNOON BUT WINDS SHOULD DIE OFF LATER THIS EVENING
AND OVERNIGHT TO GENERALLY 5KT OR BELOW EVERYWHERE.
OUTLOOK...EXPECTING GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND WITH A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS
AND RESTRICTIONS FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
17-23Z 23-05Z 05-11Z 11-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...TDP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...TDP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1044 AM EDT FRI JUL 31 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL BUILD IN BEHIND A DEPARTING COLD FRONT TODAY
AND REMAIN IN PLACE THROUGH THE WEEKEND. LOW LEVEL MOISTURE WILL
GRADUALLY RETURN THROUGH NEXT WEEK AS ANOTHER COLD FRONT APPROACHES
FROM THE NORTH.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM EDT FRIDAY...FORECAST RUNNING PRETTY MUCH ON TRACK
WITH NOT MUCH IN THE WAY OF SENSIBLE WEATHER TO WRITE HOME ABOUT.
DESPITE THE HEAT...A FAIRLY NICE DAY WITH DEWPOINTS LOWER IN THE
WAKE OF THE WEAK FRONTAL PASSAGE. VERY LITTLE CHANGES MADE TO THE
GRIDS THIS MORNING...HAVE UPDATED TEMPS AND DEWPOINTS BASED ON
TRENDS AND IT IS POSSIBLE THAT HIGHS MIGHT BE JUST A TOUCH LOWER
THAN FORECAST BUT WILL CONTINUE TO MONITOR. POPS LOOK GOOD FOR
NOW...SPC DAY1 OUTLOOK DOES INCLUDE EXTREME SOUTHEAST PORTIONS OF
THE CWA IN GENERAL THUNDER BUT LOOKING AT THE HRRR AND OTHER CAMS
SEEMS WE WILL BE PRETTY HARD-PRESSED TO SEE CONVECTION TODAY. CLOUDS
WILL CONTINUE TO SCATTER OUT OVER THE NEXT COUPLE OF HOURS.
1045 UTC UPDATE...SKY COVER WAS UPDATED FORM INFRARED SATELLITE
IMAGERY...RESULTING IN A DECREASE. POPS WERE ADJUSTED DOWN PER
TRENDS.
AT 300 AM EDT FRIDAY...AN UPPER RIDGE WILL SLOWLY RETROGRESS TODAY AND
TONIGHT FROM THE SOUTHERN PLAINS TO THE SOUTHERN ROCKIES...WHILE AN
UPPER TROUGH AMPLIFIES OVER THE EASTERN USA. A COLD FRONT WILL MOVE
SLOWLY SOUTH AND OUT OF OUR AREA...STALLING NEAR THE COAST OF THE
CAROLINAS AND GA. MOISTURE ASSOCIATED WITH THIS BOUNDARY APPEARS TO
GENERALLY REMAIN JUST SE OF OUR AREA...OFFERING LITTLE SUPPORT FOR
CONVECTION. TEMPERATURES WILL RUN NEAR NORMAL TODAY AND TONIGHT AS
WEAK COOL ADVECTION IS OFFSET BY LIMITED DOWNSLOPE WARMING FLOW IN
LIGHT NORTHERLY WINDS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 150 AM FRIDAY...QUIET WEATHER EXPECTED THRU THE SHORT RANGE.
AN UPPER TROF REMAINS ACROSS MUCH OF THE ERN CONUS WITH NO
SIGNIFICANT SHORT WAVE ENERGY MOVING THRU THE TROF. AT THE SFC...
DRY HIGH PRESSURE BUILDS IN ACROSS THE AREA SAT AND SUN. GUIDANCE
BLEND SHOWS DEW POINTS MIXING OUT INTO THE 50S ACROSS THE AREA BOTH
DAYS. THIS COMBINED WITH RELATIVELY WARM MID LEVEL AIR WILL LEAD TO
LITTLE TO NO CAPE EACH AFTERNOON...RESULTING IN VERY LOW POTENTIAL
FOR DEEP MOIST CONVECTION. A REMNANT COLD FRONT BOUNDARY WILL BE
CLOSE BUT SOUTH OF THE AREA PROVIDING LITTLE TO NO LOW LEVEL
CONVERGENCE FOR THE AREA. THEREFORE...HAVE GONE WITH A DRY FCST.
EXPECT TEMPS TO BE NEAR TO A LITTLE ABOVE NORMAL THRU THE PERIOD.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 255 AM FRIDAY...GUIDANCE IS IN DECENT AGREEMENT THRU THE
PERIOD. EAST COAST TROF FLATTENS THRU THE PERIOD WITH WLY FLOW
DEVELOPING ACROSS THE AREA AS HEIGHTS RISE. THIS ALLOWS A SERIES OF
SHORT WAVES TO MOVE ACROSS OR NEAR THE AREA. THE DRY HIGH PRESSURE
OVER THE AREA SLOWLY MODERATES THEN DISSIPATES AS A COLD FRONT DROPS
SOUTH TOWARD THE AREA. THE COLD FRONT INITIALLY STALLS...THEN MOVES
INTO THE AREA THU AS A LOW PRESSURE AREA TRACKS FROM THE OH VALLEY
OFF THE MID ATLANTIC COAST. THE RESULT IS AN INCREASE IN LOW LEVEL
MOISTURE AND INSTABILITY THRU THE PERIOD. THE BEST FORCING...AND
RESULTANT CONVECTION...WILL BE WED AND THU...WITH A DRY FCST MON AND
ONLY ISOLATED CONVECTION TUE ACROSS THE MTNS. WITH THE RISING
HEIGHTS AND LINGERING HIGH PRESSURE MON AND TUE...TEMPS WILL BE
ABOVE NORMAL. TEMPS SLOWLY FALL WED AND THU...BUT REMAIN ABOVE
NORMAL.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
AT KCLT...VFR. GUIDANCE DOES NOT FAVOR VSBY OR CIG RESTRICTIONS.
WINDS WILL GENERALLY FAVOR THE N OR NE...WITH LIMITED GUST
POTENTIAL. CONVECTION IS NOT EXPECTED TODAY IN DRIER AIR BEHIND A
DEPARTING COLD FRONT.
ELSEWHERE...RESTRICTIONS ARE NOT FAVORED AT TAF SITES BY MODEL
GUIDANCE...AS DRIER AIR MOVES IN BEHIND A DEPARTING COLD FRONT.
WINDS WILL GENERALLY FAVOR THE N...WITH ONLY LIMITED GUSTS.
CONVECTION IS NOT EXPECTED AT TAF SITES THIS AFTERNOON.
OUTLOOK...EXPECTING GENERALLY DRY AND QUIET WEATHER THROUGH THE
WEEKEND WITH A GRADUAL INCREASE IN CHANCES FOR SHOWERS/THUNDERSTORMS
AND RESTRICTIONS FOR THE START OF THE NEW WORK WEEK.
CONFIDENCE TABLE...
14-20Z 20-02Z 02-08Z 08-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 95%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...TDP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JAT/TDP
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
700 PM CDT SAT AUG 1 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...DISSIPATING SHOWERS APPROACHING SOUTH PADRE ISLAND
HAVE A LOW PROBABILITY OF IMPACTING KBRO THROUGH 9 PM. NO THUNDER
IS ASSOCIATED WITH THIS SMALL AREA OF RAIN AS IT DRIFTS SOUTHWEST
AT AROUND 15 MPH. CEILINGS ASSOCIATED WITH THIS AREA OF RAIN AND
OTHER CLOUDS THROUGH MUCH OF DEEP SOUTH TEXAS ARE IN THE VFR RANGE
WITH NO MVFR OR IFR EXPECTED IN THE NEXT 24 HOURS. PROBABILITIES
FROM HIGH RESOLUTION MODELS CONTINUES TO INDICATE LOW
PROBABILITIES OF ANY AVIATION IMPACTS FROM LOW CLOUDS OR LOW
VISIBILITIES. WINDS WILL CONTINUE TO BE LIGHT AND VARIABLE TONIGHT
BECOMING SOUTHEAST LIGHT TO MODERATE SUNDAY WITH GUSTS BETWEEN 15
AND 20 KNOTS IN THE LATE MORNING AND AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 304 PM CDT SAT AUG 1 2015/
SHORT TERM /NOW THROUGH SUNDAY NIGHT/...SATELLITE IMAGES THIS
AFTERNOON INDICATE MOSTLY MID TO HIGH CLOUDS NEAR THE COAST WITH A
SCATTERED CU FIELD ACROSS THE WESTERN PORTIONS OF THE DEEP SOUTH
TEXAS. THE LATEST BRO RADAR CONTINUES TO SHOW SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS OVER THE GULF OF MEXICO WATERS...20 TO
60 NAUTICAL MILES EAST OF PADRE ISLAND. THE WEAK 500MB
LOW/INVERTED TROUGH ACROSS THE WESTERN GULF OF MEXICO THIS
AFTERNOON WILL CONTINUE TO PROVIDE LOW TO MID LEVEL MOISTURE OVER
THE WESTERN GULF OF MEXICO AND ALONG THE LOWER TEXAS COAST. THE
12Z BRO SOUNDING SHOWS PRECIPITABLE WATERS OF 1.97 INCHES. THIS
WILL SUPPORT A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE COASTAL SECTIONS OF DEEP SOUTH TEXAS FOR THE REST OF THIS
AFTERNOON WITH DRIER AIR FARTHER INLAND. THE LATEST HRRR KEEPS
MOST...IF NOT ALL...OF THE CONVECTION OFFSHORE AND SOUTH OF THE
RIO GRANDE RIVER NOW THROUGH THIS EVENING. CONVECTION IS EXPECTED
TO DECREASE IN COVERAGE THIS EVENING BEFORE REDEVELOPING OVER THE
GULF WATERS AFTER MIDNIGHT. THE WEAK MID TO UPPER LEVEL FEATURE IS
EXPECTED TO MOVE WESTWARD ACROSS NORTHEAST MEXICO TONIGHT INTO
SUNDAY. LINGERING MOISTURE COMBINED WITH DAYTIME HEATING WILL
PROVIDE A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE
LOWER PORTIONS OF THE RIO GRANDE VALLEY ON SUNDAY.
LONG TERM /MONDAY THROUGH SATURDAY/...THE MAIN ISSUE IN THE
LONGER RANGE PERIOD WILL BE THE HEAT POTENTIAL ACROSS THE RGV. THE
GFS AND ECMWF BOTH RESTRENGTHEN THE 500 MB RIDGING IN PLACE OVER
THE SOUTH CENTRAL PLAINS STATES NEXT WEEK. THIS WILL RESULT IN A
DRIER AND MORE STABLE AIRMASS OVER DEEP SOUTH TX ONCE AGAIN
YIELDING ABOVE NORMAL TEMPS THROUGH DAY 7. THE DEEPER LAYER
MOISTURE VALUES REMAIN PRETTY LIMITED ACROSS THE AREA THROUGH THE
EXTENDED RANGE PERIOD. ONLY A VERY SHALLOW MOISTURE LAYER MAY
PERSIST ON THROUGH DAY 7 WHICH WILL ALLOW FOR SOME LOW LEVEL CLD
COVER TO PERSIST ON THROUGH THE PERIOD. OTHERWISE EXPECT NEAR
ZERO RAIN CHANCES TO PREVAIL.
THE GFS MEX AND ECMWF MODEL HIGH/LOW TEMPS THROUGH THE PERIOD ARE
IN PRETTY DECENT AGREEMENT. SO WILL GO WITH A GENERAL 50/50 BLEND
OF THE TWO MODEL SETS FOR TEMPS. THE GFS MEX POPS STILL TRY TO
TREND TOWARDS SOME SLGT CHC POPS LATE IN THE PERIOD. I BELIEVE
THAT THIS IS MODEL TREND IS BEING SKEWED HIGH DUE TO CLIMO
INFLUENCES. SO WILL GO CLOSER TO THE ECMWF POPS IN THE LONG TERM.
MARINE...NOW THROUGH SUNDAY NIGHT...BUOY020 IS CURRENTLY REPORTING
SEAS OF 1 FOOT WITH NORTH WINDS NEAR 4 KNOTS. LIGHT AND VARIABLE
WINDS WILL PREVAIL ACROSS THE LOWER TEXAS COASTAL WATERS NOW THROUGH
SUNDAY NIGHT DUE TO A WEAK PRESSURE GRADIENT ACROSS THE WESTERN
GULF. WINDS AND SEAS WILL BE HIGHER IN AND NEAR THUNDERSTORMS
ASSOCIATED WITH THE WEAK MID TO UPPER LEVEL DISTURBANCE OVER THE
WESTERN GULF.
MONDAY THROUGH THURSDAY...THE PGF WILL START OF NEXT WEEK FAIRLY
WEAK ALLOWING FOR FAIRLY LOW WINDS AND SEAS TO PREVAIL. THE PGF
WILL THEN START TO STRENGTHEN SOMEWHAT STARTING LATE TUES/WED AS A
SURFACE LOW DEVELOPS OVER THE SOUTHERN PLAINS STATES. THIS MAY
PUSH THE WINDS AND SEAS UP LATE IN THE MARINE FORECAST PERIOD TO
POSSIBLY PRODUCE SOME SCEC CONDITIONS WED/THURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL 77 92 79 94 / 10 20 10 10
BROWNSVILLE 76 94 78 95 / 10 20 10 10
HARLINGEN 75 95 77 98 / 10 40 10 10
MCALLEN 76 99 79 102 / 10 30 10 10
RIO GRANDE CITY 75 101 78 104 / 10 20 10 10
SOUTH PADRE ISLAND 78 88 80 90 / 10 20 10 10
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
59...AVIATION/SHORT TERM
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
309 PM CDT FRI JUL 31 2015
.SHORT TERM (TONIGHT THROUGH SATURDAY NIGHT)...HAVE FINALLY
DEVELOPED SOME ISOLATED TO SCATTERED SHOWERS AND A FEW
THUNDERSTORMS ACROSS THE AREA THIS AFTERNOON. HRRR MODEL HANDLING
THIS REASONABLY WELL...ENDS MOST OF THE ACTIVITY BY ABOUT 02Z. HAVE
20 POPS AREA WIDE FOR THE EVENING...WITH 10S AND 20S AFTER
MIDNIGHT. GLOBAL MODELS CONTINUE TO STRUGGLE WITH QPF...GFS
DEFINITELY STILL TOO AGGRESSIVE. SOMETHING OF A MIX BETWEEN NAM
AND ECMWF APPEARS THE BEST. THAT SAID...BOTH OF THOSE MODELS ARE
QUIET ON SATURDAY...EXCEPT IN MARINE AREA. HAVE CUT POPS FOR
INLAND AREAS IN THE MORNING...BUT WILL LEAVE A 20 POP AREA WIDE
FOR THE AFTERNOON AS HIGH MOISTURE AIR WILL STILL BE IN PLACE AND
COULD GET SOME SHOWERS TO POP UP ONCE AGAIN.
WITH NO MAJOR PATTERN CHANCE...EXPECT TEMPERATURES TOMORROW TO
APPROACH THE SAME VALUES WE/RE SEEING TODAY AS WE SHOULD KEEP A
LIGHT AND VARIABLE WIND...NOT THE ONSHORE FLOW WE ARE USED TO THIS
TIME OF YEAR. HAVE HIGHS MAINLY IN THE UPPER 90S TO AROUND 100
ACROSS THE AREA. HEAT INDEX VALUES WILL BE AT LEAST BETWEEN 100
AND 105...BUT COULD BE 105 TO 109 IF WE DON`T MIX OUT THE NEAR
SURFACE MOISTURE.
&&
.LONG TERM (SUNDAY THROUGH FRIDAY)...EXTENDED FORECAST LOOKS
RELATIVELY STRAIGHTFORWARD WITH UPPER RIDGE AXIS REPOSITIONING
ITSELF OVER THE SOUTHERN PLAINS AND SURFACE LEE DEVELOPMENT
GENERATING TYPICAL ONSHORE FLOW REGIME ACROSS THE COASTAL BEND. ANY
LINGERING PRECIPITATION CHANCES WITH A DECAYING BOUNDARY ON SUNDAY
SHOULD BE CONFINED TO OFFSHORE ZONES...THEN A DRY FORECAST THROUGH
THE WEEK.
TEMPERATURES WILL REMAIN A CATEGORY OR SO ABOVE NORMAL THROUGH THE
PERIOD. HEAT INDEX LEVELS WILL FLIRT WITH SPS CRITERIA ON A DAILY
BASIS...THOUGH ACTUAL ADVISORY CRITERIA HEAT APPEARS UNLIKELY.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 76 98 76 96 77 / 20 20 10 10 10
VICTORIA 74 100 74 98 75 / 20 20 10 10 10
LAREDO 78 103 78 103 78 / 20 20 10 10 0
ALICE 75 100 75 98 75 / 20 20 10 10 10
ROCKPORT 76 95 79 91 80 / 20 20 10 10 10
COTULLA 77 102 75 103 76 / 20 20 10 0 0
KINGSVILLE 75 99 76 98 76 / 20 20 10 10 10
NAVY CORPUS 78 92 79 90 80 / 20 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
PZ/83...SHORT TERM
JV/71...LONG TERM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1050 AM CDT FRI JUL 31 2015
.UPDATE...
ONE NOTE...AFTER CHECKING THROUGH THE TEMPERATURES DECIDED TO UP
THE HIGHS FOR TODAY A BIT TO BE MORE IN LINE WITH THE MAV
GUIDANCE. DRIER AIR FILTERING IN FROM THE NORTHEAST WILL LIKELY
AID IN A BIT HIGHER NUMBERS.
40
&&
.PREV DISCUSSION... /ISSUED 1036 AM CDT FRI JUL 31 2015/
DISCUSSION...
A COLD FRONT WAS ENTERING INTO THE NORTHEASTERN COUNTIES OF THE
FORECAST AREA AT MID MORNING...WITH A PREFRONTAL TROUGH ACROSS
GALVESTON BAY THROUGH METRO HOUSTON AND INTO THE CLL AREA. ANOTHER
TROUGH WAS OUT IN THE OPEN WATERS OF THE GULF. ISOLATED SHOWERS
HAVE ENDEAVORED TO DEVELOP OVER THE INLAND AREAS SOUTH OF THE
PREFRONTAL TROUGH WHILE SCATTERED LARGER SHOWERS WERE OVER THE
OPEN WATERS OF THE GULF EAST OF THAT SURFACE TROUGH.
THE HIGH RES SHORT RANGE MODELS LOOKED FAIRLY SIMILAR FOR THE
OUTLOOK TODAY. LIKED THE HRRR WHICH HAS ISOLATED CONVECTION ALONG
AND SOUTHWEST OF A LINE FROM ABOUT CLL TO HOUSTON TO GALVESTON
LATE THIS MORNING THROUGH THE EARLY AFTERNOON. AS THE FRONT
CONTINUES MOVING SOUTHWESTWARD...THE RAIN CHANCES WILL PUSH MORE
OVER THE SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EARLY
EVENING.
THE OTHER ISSUE OF NOTE WILL BE THE HEAT INDEX. VALUES ARE STILL
FORECAST TO REACH ADVISORY CRITERIA OVER THE COAST DURING THE LATE
AFTERNOON PERIOD. THE DRIER AIR BEHIND THE FRONT WILL LIKELY HAVE
AN IMPACT OVER CHAMBERS AND MAYBE GALVESTON COUNTY. SINCE THE
TIMING IS UNCERTAIN AT THIS TIME...WILL KEEP THE HEAT ADVISORY UP
FOR THE IMMEDIATE COASTAL COUNTIES BUT WILL DROP COUNTIES LATER
TODAY IF NEEDED.
TWEAKED THE POPS AND WEATHER A BIT TO ACCOUNT FOR THE LATEST RADAR
AND MODEL TRENDS.
40
PREV DISCUSSION... /ISSUED 414 AM CDT FRI JUL 31 2015/
DISCUSSION...
OVERNIGHT CONVECTION OVER THE BRAZOS VALLEY CONTINUES TO DIMINISH
AS IT EXITS THE FORECAST AREA...WITH VERY WARM TEMPERATURES
PERSISTING ACROSS SOUTHEAST TEXAS EARLY THIS MORNING. SURFACE
ANALYSIS AT 05Z SHOWED A PLUME OF 75+ DEGREE DEW POINTS DRAPED
ALONG THE TEXAS COAST AND EXTENDING INTO NORTHEAST LOUISIANA.
THIS... COMBINED WITH LEFTOVER CLOUDS FROM LAST NIGHT/S STORMS...
WAS CONTRIBUTING TO HEAT INDICES IN THE LOW TO MID 90S AS OF 3 AM
CDT AT A FEW SITES. A WEAK FRONTAL BOUNDARY WAS ALSO ANALYZED ON
THIS MAP STRETCHING NORTH TEXAS AND ON INTO NORTHERN LOUISIANA.
THIS FRONT WILL PLAY A MAJOR ROLE IN HOW THE WEATHER EVOLVES TODAY
FOR THE REGION... BOTH IN TERMS OF THUNDERSTORM CHANCES AS WELL AS
CONCERNS ABOUT HEAT.
THE 00Z LAKE CHARLES SOUNDING REPORTED A PRECIPITABLE WATER VALUE
OF 2.26 INCHES... WITH OVERNIGHT GPS-MET MEASUREMENTS ACROSS THE
REGION SHOWING A SIMILARLY MOIST AIRMASS /2.1 TO 2.3 INCHES AROUND
THE HOUSTON METRO AND ALONG THE COAST/. HIGH RESOLUTION GUIDANCE
IS FAIRLY CONSISTENT WITH DEVELOPING SCATTERED SHOWERS AND
THUNDERSTORMS ALONG THE FRONT AS IT SLOWLY DROPS SOUTHWESTWARD
TODAY... BUT AGREEMENT IS POOR IN THE ACTUAL TIMING OF THIS
FEATURE AND CONSEQUENTLY THE LOCATION OF THE GREATEST AREAL
COVERAGE.
THE GFS APPEARS TO BE BY FAR THE MOST AGGRESSIVE AND SWEEPS
MOISTURE AWAY FROM THE INTERSTATE 45 CORRIDOR AND POINTS EAST BY
18Z. COMPARISON OF SURFACE THETA-E FIELDS HOWEVER /WHICH REPRESENT
MOISTURE AND INSTABILITY PRESENT/ REVEAL STABILIZATION FOR THE
EASTERN HALF OF THE REGION CLOSER TO 00Z... WITH RELATIVELY GOOD
AGREEMENT BETWEEN BOTH HIGHER RESOLUTION AND SYNOPTIC MODELS ON
THIS SOLUTION. BASED ON THIS... HIGHLIGHTING HIGHEST RAIN CHANCES
WEST OF THE INTERSTATE 45 CORRIDOR TODAY ALONG AND AHEAD OF THE
ANTICIPATED FRONTAL POSITION. ADDITIONALLY... A DRY SUB-CLOUD
LAYER AND DCAPE VALUES 1100-1300 J/KG THIS AFTERNOON RAISES
CONCERNS FOR AT LEAST AN ISOLATED GUSTY WIND THREAT FROM STRONGER
THUNDERSTORM ACTIVITY.
A LATER FRONTAL PASSAGE ALSO MEANS THAT STIFLING CONDITIONS WILL
PERSIST AHEAD OF THE FRONT TODAY AND HAVE GONE AHEAD AND ISSUED A
HEAT ADVISORY FOR THE COASTAL COUNTIES OF MATAGORDA... BRAZORIA...
GALVESTON... AND CHAMBERS. HEAT INDICES IN THESE AREAS REACHED 109
TO 111 DEGREES YESTERDAY. WITH THE ANTICIPATED SLOW PROGRESSION
OF THE FRONT TODAY COMBINED WITH NAEFS ANOMALIES HIGHLIGHTING
ANOMALOUS TEMPERATURES AGAIN ALONG THE COAST /A RETURN INTERVAL
OF APPROXIMATELY ONCE EVERY 10 YEARS/... WANTED TO HIGHLIGHT THE
INCREASED POTENTIAL FOR HEALTH IMPACTS. IF THE FRONT MOVES THROUGH
FASTER THAN ANTICIPATED HOWEVER... DRIER AIR FILTERING IN BEHIND
THE FRONT WILL ACTUALLY HELP LOWER HEAT INDEX VALUES AND ADVISORY
CRITERIA MAY NOT BE MET.
FOR THE REMAINDER OF THE SHORT TERM... THE FRONT IS EXPECTED TO
PUSH OFF THE COAST TONIGHT. DRIER AIR FILTERING IN BEHIND THE
FRONT WILL HELP LIMIT RAIN CHANCES OVER ALL BUT THE COASTAL WATERS
ON SATURDAY. THIS SLIGHTLY DRIER AIR MAY ALSO ALLOW FOR SOME
OVERNIGHT LOWS IN THE UPPER 60S IN THE PINEY WOODS REGION... WITH
LOW 70S TO NEAR 80 POSSIBLE ELSEWHERE. HIGH TEMPERATURES ARE NOT
EXPECTED TO DIFFER MUCH FROM TODAY ON SATURDAY BUT A DRIER AIRMASS
IN PLACE WILL HELP MITIGATE AGAINST HIGHER HEAT INDEX VALUES.
THE REGION WILL REMAIN ON THE EASTERN PERIPHERY OF THE UPPER RIDGE
ON SUNDAY AND THROUGH THE REST OF THE FORECAST PERIOD... WITH THE
CENTER OF THIS FEATURE SHIFTING A BIT AROUND THE SOUTHERN PLAINS
DURING THIS TIME. LOW THUNDERSTORM CHANCES WILL CONTINUE IN THE
VICINITY OF THE STALLED FRONTAL BOUNDARY WITH DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES INLAND PERSISTING INTO THE MIDDLE OF
NEXT WEEK.
HUFFMAN
MARINE...
STORMS HAVE DEPARTED THE WATERS BUT MORE COULD COMING LATE THIS
MORNING THROUGH EVENING. WINDS WILL GENERALLY BE VARIABLE NORTHERLY
TO EASTERLY ACROSS THE UPPER TEXAS COASTAL WATERS WITH AN AFTERNOON
SEABREEZE FORMING. EVENTUALLY A DIFFUSE COLD FRONT SAGS OUT INTO THE
GULF WATERS LATE TONIGHT AND WINDS INCREASE SLIGHTLY. 850MB FRONT
APPEARS TO STALL WELL OFFSHORE AND SHOULD BECOME A FOCUS FOR
REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS BUT PROBABLY JUST SE OF THE
UPPER TEXAS COASTAL WATERS. WILL NEED TO KEEP AN EYE ON THE REMAINS
OF THE BOUNDARY SATURDAY AFTERNOON-SUNDAY AS THE GULF IS PLENTY WARM
ENOUGH AND SHEAR RELAXES. MOISTURE SURGES BACK INTO THE AREA LATE
SUNDAY AND SOUTH TO SOUTHEASTERLY FLOW RETURNS AND CONTINUES THROUGH
FRIDAY.
45
AVIATION...
VFR FOR NOW BUT MAY GET A FEW SPOTS WITH MIFG AROUND SUNRISE MAINLY
THE MORE RURAL SITES CXO NORTHWARD. CHALLENGING FORECAST FOR TODAY.
DRY AIR SHOULD INTRUDE INTO THE REGION FROM THE NORTHEAST BUT A FEW
OF THE MODELS APPEAR TOO QUICK TO DRY THINGS OUT. L/V WINDS WILL BE
THE NORTH UNTIL THE DIFFUSE FROPA. AM THINKING THAT CLL-HOU-SGR-LBX
MAY SEE SOME THUNDER CLOSE BY THIS AFTERNOON AND WILL LIKELY ADD
THIS IN THE 12Z PACKAGE IF NOT SOONER. IAH MAY BE ON THE NORTHERN
FRINGE OF WHERE POOLED MOISTURE AND SAGGING BOUNDARY INTERACT SO FOR
NOW WILL PROBABLY LEAVE VCTS OUT BUT IT WILL BE CLOSE. DEEP MIXING
AGAIN TODAY WITH LIGHT WINDS IN THE PROFILE SO STORMS SHOULD BE SLOW
MOVING. DRYING NORTHEASTERLY TO EASTERLY FLOW SHOULD OVERSPREAD
IAH/HOU BY LATE AFTERNOON/EARLY EVENING LEADING TO CLEAR SKIES.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 99 73 98 74 99 / 30 10 10 10 10
HOUSTON (IAH) 100 74 98 75 99 / 20 10 10 10 10
GALVESTON (GLS) 95 80 94 81 92 / 30 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...MATAGORDA.
GM...NONE.
&&
$$
DISCUSSION...40
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1036 AM CDT FRI JUL 31 2015
.DISCUSSION...
A COLD FRONT WAS ENTERING INTO THE NORTHEASTERN COUNTIES OF THE
FORECAST AREA AT MID MORNING...WITH A PREFRONTAL TROUGH ACROSS
GALVESTON BAY THROUGH METRO HOUSTON AND INTO THE CLL AREA. ANOTHER
TROUGH WAS OUT IN THE OPEN WATERS OF THE GULF. ISOLATED SHOWERS
HAVE ENDEAVORED TO DEVELOP OVER THE INLAND AREAS SOUTH OF THE
PREFRONTAL TROUGH WHILE SCATTERED LARGER SHOWERS WERE OVER THE
OPEN WATERS OF THE GULF EAST OF THAT SURFACE TROUGH.
THE HIGH RES SHORT RANGE MODELS LOOKED FAIRLY SIMILAR FOR THE
OUTLOOK TODAY. LIKED THE HRRR WHICH HAS ISOLATED CONVECTION ALONG
AND SOUTHWEST OF A LINE FROM ABOUT CLL TO HOUSTON TO GALVESTON
LATE THIS MORNING THROUGH THE EARLY AFTERNOON. AS THE FRONT
CONTINUES MOVING SOUTHWESTWARD...THE RAIN CHANCES WILL PUSH MORE
OVER THE SOUTHWESTERN COUNTIES DURING THE LATE AFTERNOON AND EARLY
EVENING.
THE OTHER ISSUE OF NOTE WILL BE THE HEAT INDEX. VALUES ARE STILL
FORECAST TO REACH ADVISORY CRITERIA OVER THE COAST DURING THE LATE
AFTERNOON PERIOD. THE DRIER AIR BEHIND THE FRONT WILL LIKELY HAVE
AN IMPACT OVER CHAMBERS AND MAYBE GALVESTON COUNTY. SINCE THE
TIMING IS UNCERTAIN AT THIS TIME...WILL KEEP THE HEAT ADVISORY UP
FOR THE IMMEDIATE COASTAL COUNTIES BUT WILL DROP COUNTIES LATER
TODAY IF NEEDED.
TWEAKED THE POPS AND WEATHER A BIT TO ACCOUNT FOR THE LATEST RADAR
AND MODEL TRENDS.
40
&&
.PREV DISCUSSION... /ISSUED 414 AM CDT FRI JUL 31 2015/
DISCUSSION...
OVERNIGHT CONVECTION OVER THE BRAZOS VALLEY CONTINUES TO DIMINISH
AS IT EXITS THE FORECAST AREA...WITH VERY WARM TEMPERATURES
PERSISTING ACROSS SOUTHEAST TEXAS EARLY THIS MORNING. SURFACE
ANALYSIS AT 05Z SHOWED A PLUME OF 75+ DEGREE DEW POINTS DRAPED
ALONG THE TEXAS COAST AND EXTENDING INTO NORTHEAST LOUISIANA.
THIS... COMBINED WITH LEFTOVER CLOUDS FROM LAST NIGHT/S STORMS...
WAS CONTRIBUTING TO HEAT INDICES IN THE LOW TO MID 90S AS OF 3 AM
CDT AT A FEW SITES. A WEAK FRONTAL BOUNDARY WAS ALSO ANALYZED ON
THIS MAP STRETCHING NORTH TEXAS AND ON INTO NORTHERN LOUISIANA.
THIS FRONT WILL PLAY A MAJOR ROLE IN HOW THE WEATHER EVOLVES TODAY
FOR THE REGION... BOTH IN TERMS OF THUNDERSTORM CHANCES AS WELL AS
CONCERNS ABOUT HEAT.
THE 00Z LAKE CHARLES SOUNDING REPORTED A PRECIPITABLE WATER VALUE
OF 2.26 INCHES... WITH OVERNIGHT GPS-MET MEASUREMENTS ACROSS THE
REGION SHOWING A SIMILARLY MOIST AIRMASS /2.1 TO 2.3 INCHES AROUND
THE HOUSTON METRO AND ALONG THE COAST/. HIGH RESOLUTION GUIDANCE
IS FAIRLY CONSISTENT WITH DEVELOPING SCATTERED SHOWERS AND
THUNDERSTORMS ALONG THE FRONT AS IT SLOWLY DROPS SOUTHWESTWARD
TODAY... BUT AGREEMENT IS POOR IN THE ACTUAL TIMING OF THIS
FEATURE AND CONSEQUENTLY THE LOCATION OF THE GREATEST AREAL
COVERAGE.
THE GFS APPEARS TO BE BY FAR THE MOST AGGRESSIVE AND SWEEPS
MOISTURE AWAY FROM THE INTERSTATE 45 CORRIDOR AND POINTS EAST BY
18Z. COMPARISON OF SURFACE THETA-E FIELDS HOWEVER /WHICH REPRESENT
MOISTURE AND INSTABILITY PRESENT/ REVEAL STABILIZATION FOR THE
EASTERN HALF OF THE REGION CLOSER TO 00Z... WITH RELATIVELY GOOD
AGREEMENT BETWEEN BOTH HIGHER RESOLUTION AND SYNOPTIC MODELS ON
THIS SOLUTION. BASED ON THIS... HIGHLIGHTING HIGHEST RAIN CHANCES
WEST OF THE INTERSTATE 45 CORRIDOR TODAY ALONG AND AHEAD OF THE
ANTICIPATED FRONTAL POSITION. ADDITIONALLY... A DRY SUB-CLOUD
LAYER AND DCAPE VALUES 1100-1300 J/KG THIS AFTERNOON RAISES
CONCERNS FOR AT LEAST AN ISOLATED GUSTY WIND THREAT FROM STRONGER
THUNDERSTORM ACTIVITY.
A LATER FRONTAL PASSAGE ALSO MEANS THAT STIFLING CONDITIONS WILL
PERSIST AHEAD OF THE FRONT TODAY AND HAVE GONE AHEAD AND ISSUED A
HEAT ADVISORY FOR THE COASTAL COUNTIES OF MATAGORDA... BRAZORIA...
GALVESTON... AND CHAMBERS. HEAT INDICES IN THESE AREAS REACHED 109
TO 111 DEGREES YESTERDAY. WITH THE ANTICIPATED SLOW PROGRESSION
OF THE FRONT TODAY COMBINED WITH NAEFS ANOMALIES HIGHLIGHTING
ANOMALOUS TEMPERATURES AGAIN ALONG THE COAST /A RETURN INTERVAL
OF APPROXIMATELY ONCE EVERY 10 YEARS/... WANTED TO HIGHLIGHT THE
INCREASED POTENTIAL FOR HEALTH IMPACTS. IF THE FRONT MOVES THROUGH
FASTER THAN ANTICIPATED HOWEVER... DRIER AIR FILTERING IN BEHIND
THE FRONT WILL ACTUALLY HELP LOWER HEAT INDEX VALUES AND ADVISORY
CRITERIA MAY NOT BE MET.
FOR THE REMAINDER OF THE SHORT TERM... THE FRONT IS EXPECTED TO
PUSH OFF THE COAST TONIGHT. DRIER AIR FILTERING IN BEHIND THE
FRONT WILL HELP LIMIT RAIN CHANCES OVER ALL BUT THE COASTAL WATERS
ON SATURDAY. THIS SLIGHTLY DRIER AIR MAY ALSO ALLOW FOR SOME
OVERNIGHT LOWS IN THE UPPER 60S IN THE PINEY WOODS REGION... WITH
LOW 70S TO NEAR 80 POSSIBLE ELSEWHERE. HIGH TEMPERATURES ARE NOT
EXPECTED TO DIFFER MUCH FROM TODAY ON SATURDAY BUT A DRIER AIRMASS
IN PLACE WILL HELP MITIGATE AGAINST HIGHER HEAT INDEX VALUES.
THE REGION WILL REMAIN ON THE EASTERN PERIPHERY OF THE UPPER RIDGE
ON SUNDAY AND THROUGH THE REST OF THE FORECAST PERIOD... WITH THE
CENTER OF THIS FEATURE SHIFTING A BIT AROUND THE SOUTHERN PLAINS
DURING THIS TIME. LOW THUNDERSTORM CHANCES WILL CONTINUE IN THE
VICINITY OF THE STALLED FRONTAL BOUNDARY WITH DRY CONDITIONS AND
ABOVE NORMAL TEMPERATURES INLAND PERSISTING INTO THE MIDDLE OF
NEXT WEEK.
HUFFMAN
MARINE...
STORMS HAVE DEPARTED THE WATERS BUT MORE COULD COMING LATE THIS
MORNING THROUGH EVENING. WINDS WILL GENERALLY BE VARIABLE NORTHERLY
TO EASTERLY ACROSS THE UPPER TEXAS COASTAL WATERS WITH AN AFTERNOON
SEABREEZE FORMING. EVENTUALLY A DIFFUSE COLD FRONT SAGS OUT INTO THE
GULF WATERS LATE TONIGHT AND WINDS INCREASE SLIGHTLY. 850MB FRONT
APPEARS TO STALL WELL OFFSHORE AND SHOULD BECOME A FOCUS FOR
REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS BUT PROBABLY JUST SE OF THE
UPPER TEXAS COASTAL WATERS. WILL NEED TO KEEP AN EYE ON THE REMAINS
OF THE BOUNDARY SATURDAY AFTERNOON-SUNDAY AS THE GULF IS PLENTY WARM
ENOUGH AND SHEAR RELAXES. MOISTURE SURGES BACK INTO THE AREA LATE
SUNDAY AND SOUTH TO SOUTHEASTERLY FLOW RETURNS AND CONTINUES THROUGH
FRIDAY.
45
AVIATION...
VFR FOR NOW BUT MAY GET A FEW SPOTS WITH MIFG AROUND SUNRISE MAINLY
THE MORE RURAL SITES CXO NORTHWARD. CHALLENGING FORECAST FOR TODAY.
DRY AIR SHOULD INTRUDE INTO THE REGION FROM THE NORTHEAST BUT A FEW
OF THE MODELS APPEAR TOO QUICK TO DRY THINGS OUT. L/V WINDS WILL BE
THE NORTH UNTIL THE DIFFUSE FROPA. AM THINKING THAT CLL-HOU-SGR-LBX
MAY SEE SOME THUNDER CLOSE BY THIS AFTERNOON AND WILL LIKELY ADD
THIS IN THE 12Z PACKAGE IF NOT SOONER. IAH MAY BE ON THE NORTHERN
FRINGE OF WHERE POOLED MOISTURE AND SAGGING BOUNDARY INTERACT SO FOR
NOW WILL PROBABLY LEAVE VCTS OUT BUT IT WILL BE CLOSE. DEEP MIXING
AGAIN TODAY WITH LIGHT WINDS IN THE PROFILE SO STORMS SHOULD BE SLOW
MOVING. DRYING NORTHEASTERLY TO EASTERLY FLOW SHOULD OVERSPREAD
IAH/HOU BY LATE AFTERNOON/EARLY EVENING LEADING TO CLEAR SKIES.
45
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 98 73 98 74 99 / 30 10 10 10 10
HOUSTON (IAH) 98 74 98 75 99 / 20 10 10 10 10
GALVESTON (GLS) 95 80 94 81 92 / 30 10 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...HEAT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: BRAZORIA...CHAMBERS...GALVESTON...MATAGORDA.
GM...NONE.
&&
$$
DISCUSSION...40
AVIATION/MARINE...33
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1249 AM CDT FRI JUL 31 2015
.AVIATION...
VFR CONDITIONS SHOULD PREVAIL FOR MOST OF THE PERIOD. DEEP
MOISTURE IS ON THE INCREASE AS A WEAK DISTURBANCE MOVES IN FROM
THE EAST. THIS FEATURE WILL BRING SCATTERED SHOWERS AND
THUNDERSTORMS TO THE AREA THIS AFTERNOON. WILL INCLUDE THE MENTION
OF VCTS FOR THE I-35 TAF SITES. CHANCES ARE MUCH TOO LOW FOR KDRT
FOR ANY MENTION. SOME OF THE THUNDERSTORMS COULD BE HEAVY...WHICH
MAY CAUSE VISIBILITIES TO DROP TO MVFR CATEGORIES OR LOWER. GUSTY
WINDS WILL ALSO BE POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 937 PM CDT THU JUL 30 2015/
UPDATE...LEADING EDGE OF THE MOISTURE PLUME FROM THE EAST HAS
ARRIVED INTO THE FAR EASTERN CWA THIS EVENING. HOWEVER...A GRADUAL
DOWNWARD TREND IN CONVECTIVE ACTIVITY WILL TAKE PLACE THROUGH THE
REMAINDER OF THE LATE EVENING WITH LOSS OF HEATING. VERY MINOR
EDITS MADE TO HOURLY T/TD/APPARENT T GRIDS BASED ON TRENDS. NO
OTHER UPDATES PLANNED THIS EVENING. DEEPER MOISTURE CONTINUES TO
MOVE WEST AND SOUTHWEST INTO THE CWA OVERNIGHT AND FRIDAY. WITH
DE-STABILIZATION TOMORROW AFTERNOON EXPECT ISOLATED TO WIDELY
SCATTERED SHOWERS AND THUNDERSTORMS OVER THE REGION. A FEW STORMS
COULD PRODUCE STRONGER DOWNDRAFTS AND WIND GUSTS GIVEN MODEL
FORECAST SOUNDINGS...AND MENTIONED IN HWO.
PREV DISCUSSION... /ISSUED 625 PM CDT THU JUL 30 2015/
AVIATION...
/00Z TAFS/
VFR CONDITIONS ARE EXPECTED ACROSS AREA SITES THROUGH FRIDAY
AFTERNOON. WINDS WILL BE FROM THE EAST AND SOUTHEAST 5 TO 10 KNOTS
THIS EVENING...BECOMING LIGHT AND VARIABLE OVERNIGHT AND PICKING
BACK UP TO 10 KNOTS FRIDAY AFTERNOON WITH HIGHER GUSTS MAINLY
ACROSS THE RIO GRANDE PLAINS. A SURGE OF LOW TO MID LEVEL MOISTURE
IS FORECAST TO PUSH ACROSS THE EASTERN HALF OF SOUTH CENTRAL TEXAS
FRIDAY AFTERNOON AND EVENING. A FEW SHOWERS AND EVEN AN ISOLATED
THUNDERSTORM COULD POP ALONG THE I-35 SITES MID/LATE FRIDAY
AFTERNOON. THIS ACTIVITY SHOULD COME TO AN END SHORTLY AFTER
SUNSET.
PREV DISCUSSION... /ISSUED 142 PM CDT THU JUL 30 2015/
SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
A VERY ISOLATED SHOT AT THUNDERSTORMS WILL BE POSSIBLE TONIGHT AS
ENERGY AND MOISTURE WILL BE MOVING IN FROM THE EAST DUE TO A COLD
FRONT PROGRESSING SOUTHWARD ACROSS THE SE CONUS. WITH THE UPPER
LEVEL STEERING WINDS BEING NORTHEAST AND EAST...SOME OF THE SHOWER
AND STORM DEVELOPMENT IN THE HI RES MODELS COULD MAKE IT AS FAR
WEST AS THE EASTERN PERIPHERY OF THE CWA. HOWEVER...AN APPRECIABLE
MOISTURE GRADIENT OVER BASICALLY THE I35 CORRIDOR SHOULD PREVENT
MUCH FROM GETTING ANY FARTHER WESTWARD. ALSO...DRY LOW LEVEL
CONDITIONS AS SEEN ON LAPS AND RUC SOUNDINGS WOULD CHALLENGE ANY
PRECIPITATION FROM REACHING THE SURFACE SO CONFIDENCE IS NOT HIGH
FOR MEASURABLE PRECIP THIS EVENING. THEREFORE LEFT THE ISOLATED
MENTION IN FOR THE EASTERNMOST AREAS OF THE CWA.
SHOULD SEE SOME SCATTERED LOW CLOUD DEVELOPMENT IN THE MORNING BUT
LESS THAN NORMAL WITH LIGHT AND VARIABLE WINDS. THE LIGHT WINDS
AND MOSTLY UNOBSTRUCTED SKY SHOULD KEEP LOWS A COUPLE DEGREES
BELOW GUIDANCE AS THEY WERE THIS MORNING.
BEST SHOT AT MEASURABLE PRECIP WILL BE IN THE AFTERNOON FRIDAY AS
THE CONTINUING WEST COLD FRONT INTERACTS WITH THE COASTAL PLAINS
SEA BREEZE. AN AREA OF ENHANCED QPF WAS NOTED IN THE NAM AND GFS
WHICH MAKES SENSE AS AN AREA OF LIFT ENOUGH TO REALIZE DECENT
INSTABILITY DURING THE AFTERNOON HOURS. STILL THINK PWATS ARE A
BIT EXAGGERATED IN THE FORECAST SOUNDINGS BUT STILL THINK A
BRIEFLY HEAVY DOWNPOUR AND GUSTY WINDS ARE STILL IN PLAY TOMORROW
AFTERNOON.
LONG TERM (SATURDAY THROUGH THURSDAY)...
MODELS ARE TRENDING A BIT DRIER OVER THE WEEKEND BUT WITH THE BEST
OPPORTUNITY FOR SOUTH CENTRAL TEXAS TO RECEIVE RAINFALL BEING
SATURDAY AS A FORECAST COMPLEX DEVELOPS IN THE PANHANDLE AND
NORTHERLY UPPER LEVEL FLOW CARRIES IT SOUTHWARD. UNSURE ABOUT HOW
FAR SOUTH THIS WILL BE ABLE TO MAKE IT BUT CONDITIONS ARE
FAVORABLE FOR A WELL SUSTAINED COLD POOL SHOULD AN ORGANIZED
SYSTEM DEVELOP. THEREFORE HIGHLIGHTED THE NORTHERN PERIPHERY OF
THE CWA ON THE PLATEAU FOR THE BEST SHOT AT RAINFALL SATURDAY.
AFTERWARDS...THE UPPER LEVEL PATTERN RETURNS TO THE SUMMER
DOLDRUMS OF HOT AND DRY THROUGH THE END OF THE WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 76 100 76 99 76 / 20 20 0 10 0
AUSTIN BERGSTROM INTL AIRPORT 74 99 73 98 75 / 20 20 0 - 0
NEW BRAUNFELS MUNI AIRPORT 76 100 74 100 75 / 20 20 10 10 0
BURNET MUNI AIRPORT 75 98 74 97 75 / 20 20 - 20 -
DEL RIO INTL AIRPORT 78 101 78 101 78 / 20 20 10 10 0
GEORGETOWN MUNI AIRPORT 75 98 74 98 76 / 20 20 0 10 0
HONDO MUNI AIRPORT 76 100 75 99 74 / 20 20 10 10 0
SAN MARCOS MUNI AIRPORT 76 99 75 98 75 / 20 20 10 10 0
LA GRANGE - FAYETTE REGIONAL 76 99 75 99 76 / 20 10 10 - 0
SAN ANTONIO INTL AIRPORT 78 99 77 99 77 / 20 20 10 10 0
STINSON MUNI AIRPORT 77 100 76 100 76 / 20 20 10 - 0
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...HAMPSHIRE
SYNOPTIC/GRIDS...OAKS
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1134 PM CDT THU JUL 30 2015
.DISCUSSION...
SEE 06Z AVIATION DISCUSSION.
&&
.AVIATION...
PRECIPITATION LASTED A BIT LONGER THAN EXPECTED BUT IS IN THE
PROCESS OF DISSIPATING. AN ISOLATED SHOWER CAN NOT BE RULED OUT AT
ANY TIME OVERNIGHT AS PW VALUES REMAIN ABOVE 2.00 INCHES. NAM12
AND THE GFS DIFFER WITH PW VALUES ON FRIDAY WITH THE NAM MORE
AGGRESSIVE WITH MOISTURE. THE RAP HAS BACKED OFF SIGNIFICANTLY
WITH MORNING PRECIP AND IS NOW WAITING ON HEATING TO TRIGGER
SHRA/TSRA. WILL LEAN TOWARD A RAP/HRRR/GFS BLEND WHICH FOCUSES
MUCH OF THE PRECIP ON FRI OVER THE SW HALF OF THE CWA. WILL CARRY
VCSH FOR KLBX...KSGR...KHOU AND KGLS. DRY AIR WILL FILTER INTO
THE AREA FROM THE NE LATE FRIDAY AFTN AND WILL END PRECIP FROM NE
TO SW TOWARD EVENING. NUMEROUS OUTFLOW BOUNDARIES AND A WEAK
PRESSURE GRADIENT MAKES FCSTING WIND DIRECTION DIFFICULT. 43
&&
.PREV DISCUSSION... /ISSUED 912 PM CDT THU JUL 30 2015/
DISCUSSION...
SHOWERS AND THUNDERSTORMS STILL DRIFTING DOWN INTO NE ZONES AT
THIS HOUR. ANOTHER IMPORTANT FEATURE...RADAR SHOWING OUTFLOW FROM
LOUISIANA CONVECTION MOVING IN FROM THE EAST. THIS OUTFLOW TO
BRING SOME GUSTY EAST AND NORTHEAST WINDS SHORTLY TO GALVESTON BAY
AND EASTERN COASTAL GULF WATERS. WIND GUSTS WERE AS HIGH AS 40
KNOTS OVER COASTAL LOUISIANA...LIKELY 30 KNOTS OR SO FOR SOME
AREAS NOW. HAVE ISSUED A MARINE WEATHER STATEMENT TO GIVE A HEADS
UP FOR THIS FEATURE AND ADJUSTED WIND GRIDS AS WELL.
OVERNIGHT...EXPECT A CONTINUED SLOW WEAKENING TREND IN SHOWER AND
THUNDERSTORM ACTIVITY OVER LAND...BUT CANT RULE OUT AN ISOLATED
SHOWER OR THUNDERSTORM ANYWHERE GIVEN THE AIRMASS CATEGORIZED BY
DEEPER MOISTURE. FOR COASTAL AREAS WILL LIKELY SEE SQUALL LINE
BRUSH AT LEAST OUTER WATERS...BUT OUTFLOW WILL MOVE FROM NE TO SW
ALONG THE COAST WITH SOME ADDITIONAL DEVELOPMENT POSSIBLE. HAVE
BUMPED UP POPS FOR COASTAL WATERS TO COVER THIS. HIGH RESOLUTION
RAPID REFRESH SUPPORTS THIS SCENARIO. 46
PREV DISCUSSION... /ISSUED 304 PM CDT THU JUL 30 2015/
DISCUSSION...
SCT CONVECTION IS OCCURRING ACROSS NORTHERN AND EASTERN AREAS THIS
AFTERNOON. THIS ACTIVITY IS MOVING SOUTHWEST...SO CENTRAL AREAS
WILL LIKELY SEE SCT CONVECTION AS WELL LATER THIS AFTERNOON AND
EVENING. NORTHERN AND EASTERN AREAS ARE MOIST AND UNSTABLE...SO
ISOLATED STRONG STORMS ARE POSSIBLE. MAX TEMPS ARE AROUND 100
ACROSS FAR INLAND AREAS...UPPER 90S CENTRAL AREAS...AND LOWER TO
MID 90S COAST. HEAT INDICES REMAIN IN THE 100 TO 107 DEGREE RANGE
THIS AFTERNOON.
THE FRONTAL BOUNDARY IS NEAR THE RED RIVER AND IN SW ARK. THIS
BOUNDARY WILL MOVE SOUTHWEST INTO NE PORTIONS OF SE TEXAS LATE
TONIGHT/EARLY FRIDAY MORNING. BEHIND THE BOUNDARY WE WILL SEE A
DRIER AIRMASS ADVECT INTO THE REGION. THE LOCATION OF BOUNDARY WILL
DETERMINE WHERE THE BEST RAIN CHCS ARE TOMORROW. SOUTH OF THE
BOUNDARY EXPECT SCT CONVECTION AGAIN WHERE PW VALUES ARE JUST
OVER 2 INCHES. WILL TAPER POPS UPWARD FROM THE NE TO SW AREAS OF
SE TX....BASED ON THE PRECIPITABLE WATER GRADIENT EXPECTATIONS
ON FRI. BY SAT MORNING THE DEEP MOISTURE WILL BE OFFSHORE AND SW
OF SE TX...SO RAIN CHCS WILL BE VERY SMALL AGAIN FROM SAT
THROUGH MID-WEEK.
NOT MUCH CHG EXPECTED IN MAX TEMPS...SOME VARIATIONS THE NEXT
COUPLE OF DAYS DUE TO DIFFERENCES IN LAYER MOISTURE LEVELS. FAR
INLAND AREAS ON SAT COULD SEE WIDESPREAD TEMPS OVR 100 DUE TO THE
VERY DRY AIRMASS THAT WILL BE IN PLACE.
MARINE...A WEAK BACKDOOR FRONT NORTH OF THE AREA WILL EFFECT THE
COAST LATE THURSDAY INTO FRIDAY. HOWEVER...THE WINDS ASSOCIATED
WITH THE FRONT SHOULD BE LIGHT ENOUGH TO BE INFLUENCED BY THE SEA
BREEZE ON FRIDAY THROUGH THE WEEKEND.
AN OFFSHORE FLOW DURING THE EARLY MORNING HOURS WILL RELAX AND
BECOME ONSHORE DURING PEAK HEATING IN THE AFTERNOON BEFORE BECOMING
SOUTHWESTERLY IN THE EVENING. RAIN CHANCES WILL BE ON THE INCREASE
TONIGHT AND FRIDAY AS POOL OF MOISTURE OVER LA AND GULF SLIDES
WESTWARD INTO THE UPPER TEXAS COASTAL WATERS.
FORECAST MODELS BUILD THE HIGH PRESSURE RIDGE BACK OVER THE COASTAL
WATERS LATE IN THE WEEKEND AND EARLY NEXT WEEK. 44
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 78 99 75 101 76 / 20 30 20 10 10
HOUSTON (IAH) 79 99 77 100 76 / 30 30 10 10 10
GALVESTON (GLS) 82 92 82 94 82 / 30 30 10 10 10
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...46
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1036 PM CDT SAT AUG 1 2015
.UPDATE...A LARGE AREA OF INCREASING WARM ADVECTION IS OCCURRING
ACROSS MN AND WI AS THE LLJ INCREASES. SOME MOISTURE TRANSPORT
WITH THAT AS WELL BUT THE ELEVATED MIXED LAYER IS VERY WARM
RESULTING HIGH VALUES OF CIN. MESOSCALE MODELS DO PRODUCE SOME
CONVECTION OVER NORTHERN AND CENTRAL WI LATE TNT INTO SUN AM. THUS LOWERED
POPS OVER SRN WI WITH BEST CHANCES TOWARD CENTRAL WI FOR THE
REMAINDER OF THE NIGHT AND INTO SUN AM.
FOR LATE SUN AFTERNOON AND EVENING LOW PRESSURE MOVES ACROSS
CENTRAL OR NORTHERN WI AND INTO NRN LOWER MI WITH A FAIRLY STRONG
COLD FRONT TO FOLLOW. THE WIND FIELD WILL INCREASE AHEAD OF THE
FRONT WITH WIND GUSTS UP TO 35 TO 40 MPH BY THE MIDDLE TO LATE
AFTERNOON. THE WELL MIXED AND VERY WARM AIRMASS WILL LIKELY DROP
THE DEWPOINTS INTO THE LOWER 60S BY LATE AFTERNOON BUT MLCAPES
MAY STILL BE 2000 J/KG. DEEP LAYER SHEAR OF 35-40 KTS AND 0-1KM
HELICITIES OVER 200 M2/S2 WILL SUPPORT A SVR TSTORM THREAT DURING
THIS TIME. AN APPROACHING UPPER TROUGH WILL RESULT IN 50 METER 500
MB HEIGHT FALLS FROM 18Z TO 06Z PROVIDING UPPER SUPPORT TO FAIRLY
STRONG LOW LEVEL FRONTOGENESIS. THUS EXPECTED STRONG TO SVR
TSTORMS FOR THIS PERIOD.
&&
.AVIATION/06Z TAFS/...ONLY SMALL CHANCES OF TSTORMS FOR THE EARLY
SUN MORNING HOURS FROM SOUTH CENTRAL WI TO SE WI AS WARM...MOIST
ADVECTION INCREASES. THE CHANCES OF STORMS WILL CONTINUE ON SUNDAY
BUT WILL BECOME MORE LIKELY FOR SE WI SUN EVE WHEN A STRONG COLD
FRONT PASSES. VFR CONDITIONS ARE EXPECTED OUTSIDE THE TSTORMS.
&&
.PREV DISCUSSION... /ISSUED 323 PM CDT SAT AUG 1 2015/
SHORT TERM...
TONIGHT - CONFIDENCE...LOW
MAIN FOCUS WILL BE PINNING DOWN CONVECTIVE TRENDS AS THE NIGHT WEARS
ALONG. 850 LLJ BECOMES MORE FAVORABLE AIMING INTO CWA WITH INCREASING
WAA AND MOISTURE ADVECTION. MODELS ARE SHOWING VARYING SOLUTIONS FOR
MCS TRACK. 1000-500 MILLIBAR THICKNESS LINES/MCS MAINTENANCE
COMPOSITE INDEX FROM SPC MESO PAGE FAVOR MORE OF A 00Z ECMWF SOLUTION.
THE 12Z NAM IS THE FURTHEST NORTH WITH PRECIP INTO CNTRL/SRN WI. THE 12Z
ECMWF HAS COME MORE IN LINE WITH OTHER MODELS SHOWING CONVECTION
ARRIVING AFTER 6Z ACROSS THE CWA. GIVEN THE PROGGD ELEVATED
CAPE/CONSENSUS OF LLJ FORCING AND MID LEVEL SHORTWAVE WILL STILL
CARRY HIGH END CHANCE POPS FOR WHOLE CWA BUT WATCHING FOR A
POTENTIAL SE CURVE TO ANY MCS THAT MIGHT TAKE SHAPE THAT COULD LEAVE
PARTS OF SRN WI MORE ON THE NORTHERN FRINGE OF A SEWD DIVING MCS TRACK
FAVORING NE IA INTO NRN IL. WATCHING AFTERNOON VSBL ANIMATION THINKING
MORE LIKELY SCENARIO IS WE WILL BE SEEING OUR ACTIVITY ORIGINATE FROM
WRN MN INTO ERN ND WHICH WOULD FAVOR SRN WI A BIT MORE. OVERALL MODEL
SOLUTIONS INCLUDING LATEST HRRR FAVOR SOME CONVECTION A BIT LATER
IN THE NIGHT ACRS SRN WI HOWEVER THERE IS SOME LOSS TO THE
ORGANIZATION AND COVERAGE IN THE LATEST HRRR RUN. AND THIS REFLECTED IN
THE LATEST SWODY1 WITH THE REMOVAL OF THE SLIGHT RISK FROM SRN WI.
SUNDAY - CONFIDENCE...MEDIUM
COULD STILL BE DEALING WITH LINGERING MORNING CONVECTION
ASSOCIATED WITH THE LLJ/500 MILLIBAR SHORTWAVE. THEN WILL HAVE TO
SEE HOW THE MESOSCALE DETAILS PLAY OUT. EVEN THE GFS SOUNDING IS
GENERATED CAPES OVER 2K SUNDAY AFTERNOON. 850 JET IS PROGGD TO
FOCUS MORE TO OUR EAST AND SOUTHEAST AS THE DAY WEARS ON. HOWEVER
SURFACE/850 FRONT WILL STILL BE HANGING BACK TO THE NORTH AND A
WSW LOW LEVEL FLOW WILL REINFORCE MOISTURE INSTABILITY AS THE DAY
WEARS ON. CWASP SHOWING SOLID MID 70S PLUS ON ALL PROGS WITH THE
GFS SHOWING 80 PLUS BY 00Z. SO GIVEN PRONOUNCED LOW LEVEL FORCING
APPROACHING WITH SURFACE/850 FRONT SWODY2 SLIGHT IS WARRANTED WITH
THE GREATEST THREAT LATER IN THE AFTERNOON.
SUNDAY NIGHT... FORECAST CONFIDENCE MEDIUM.
SYNOPTIC AND MESOSCALE MODELS ARE IN FAIR AGREEMENT WITH
THUNDERSTORMS DEVELOPING ALONG THE COLD FRONT AS IT TRACKS FROM
CENTRAL WI DOWN THROUGH SOUTHEAST WI AND NORTHERN IL LATE SUNDAY
AFTERNOON THROUGH SUNDAY EVENING. I WENT WITH LIKELY POPS IN
SOUTHEAST WI SUNDAY EVENING... BUT IT MAY JUST BE A BROKEN LINE.
SHOWERS AND STORMS SHOULD WIND DOWN QUICKLY AFTER MIDNIGHT AS DRY
AIR SETTLES IN BEHIND THE FRONT.
EXPECTING HIGH CAPE AND SHEAR JUST AHEAD OF THE FRONT... ENOUGH TO
PRODUCE LARGE HAIL AND DAMAGING WINDS WITH ANY STRONG THUNDERSTORMS.
A TORNADO IS A REMOTE POSSIBILITY GIVEN THE LIMITED LOW LEVEL SHEAR.
LONG TERM...
MONDAY THROUGH WEDNESDAY... FORECAST CONFIDENCE HIGH.
NORTHWEST FLOW WILL DOMINATE THE GREAT LAKES REGION FOR THE FIRST
PART OF THE WORK WEEK AS AN UPPER LOW REMAINS STATIONED OVER QUEBEC.
HIGH PRESSURE AT THE SURFACE WILL ALLOW FOR FAIRLY LIGHT WINDS.
TEMPS WILL BE AROUND SEASONAL NORMAL MONDAY AND TUESDAY... THEN
SLIGHTLY COOLER IN THE MID 70S WEDNESDAY DUE TO NORTHEAST BREEZE OFF
THE LAKE.
THURSDAY THROUGH SUNDAY... FORECAST CONFIDENCE MEDIUM.
MODELS TRY TO GENERATE AN MCS OVER THE NORTHERN PLAINS THAT TRACKS
SOUTHEAST THROUGH THE MIDWEST THURSDAY AND POSSIBLY ANOTHER ONE INTO
FRIDAY. THE GFS IS MAINTAINING PRECIP CHANCES IN SOUTHERN WI WITH
THIS SYSTEM AND APPEARS TO HAVE SOME CONVECTIVE FEEDBACK ISSUES...
WHILE THE 12Z ECMWF SHIFTED THE MAIN CHANCES FARTHER SOUTH.
EXPECT DRY HIGH PRESSURE TO SETTLE BACK INTO THE GREAT LAKES REGION
BY FRIDAY NIGHT AND KEEP PRECIP CHANCES MINIMAL THROUGH THE WEEKEND.
TEMPERATURES SHOULD BE IN THE 70S.
AVIATION/00Z TAFS/...VFR CONDITIONS AT LEAST INTO THIS EVENING.
MAIN FOCUS FOR CONVECTIVE DEVELOPMENT ARRIVES LATER TONIGHT INTO
SUNDAY MORNING AS MORE PRONOUNCED LLJ AIMS INTO SRN WI. STILL SOME
TRACK UNCERTAINTY ON MCS BUT OVERALL MOIST ADVECTION WITH 850 LLJ
AND SHORTWAVE ACTIVITY WARRANTS THE CHANCE OF STORMS LATER TONIGHT
INTO SUNDAY MORNING. POCKETS OF MVFR CIGS/VSBYS WITH ANY STRONGER
STORMS. MESOSCALE DETAILS AFTER OVERNIGHT/EARLY MORNING STORMS WILL
DICTATE STORM EVOLUTION/SEVERITY ON SUNDAY AFTERNOON/EVENING AS
SURFACE LOW AND COLD FRONT INTERACT WITH POTENTIALLY VERY UNSTABLE
AIRMASS. IN ADDITION WITH LOW LEVEL JET STRENGTHENING OVERNIGHT SOME
LOW LEVEL WIND SHEAR IS POSSIBLE.
MARINE...SMALL CRAFT ADVISORY HOISTED FOR SUNDAY AS PRESSURE
GRADIENT TIGHTENS UP AHEAD OF APPROACHING SURFACE LOW PRESSURE
SYSTEM. SW WINDS SHOULD RAMP UP PRETTY QUICK IN THE MORNING AND GET
RATHER GUSTY. COLD FRONT MAY SPAWN SOME STRONG TSTORMS LATE
AFTN/ERLY EVE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 9 AM TO 6 PM CDT SUNDAY FOR LMZ643>646.
&&
$$
UPDATE...GEHRING
TONIGHT/SUNDAY AND AVIATION/MARINE...COLLAR
SUNDAY NIGHT THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
942 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 942 PM CDT SAT AUG 1 2015
IT LOOKS LIKE THE CHANCES FOR STORMS THE REST OF THE NIGHT HAS
BECOME PRETTY MARGINAL. THE BEST FORCING WILL BE AHEAD OF SHORT
WAVE TROUGH CURRENTLY COMING OUT OF SOUTHERN MANITOBA WITH SOME
STORMS AHEAD OF IT OVER NORTH DAKOTA. THE LOW LEVEL JET WILL BE
FOCUSED INTO NORTHERN MINNESOTA AND WISCONSIN AHEAD OF THIS WAVE
AND MAY HELP SOME ADDITIONAL STORMS FIRE THERE OVERNIGHT. THE
02.00Z HRRR-CR SEEMS TO HAVE LATCHED ONTO THIS SOLUTION AND WOULD
SUGGEST THE ENTIRE AREA WILL BE DRY INTO SUNDAY MORNING. HAVE
REMOVED THE RAIN CHANCES FOR ALL BUT THE INTERSTATE 94 CORRIDOR
FOR LATE TONIGHT INCASE SOME ACTIVITY WITH THE LOW LEVEL JET SLIPS
INTO THE AREA. NOT EXPECTING ANY SEVERE WEATHER OVERNIGHT AND HAVE
UPDATED ALL PRODUCTS TO REFLECT THIS.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 245 PM CDT SAT AUG 1 2015
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES TONIGHT INTO SUN
EVENING...ANY SEVERE THREAT TONIGHT AND AGAIN SUN AFTERNOON/EVENING.
DATA ANALYSIS AT 18Z HAD HIGH PRESSURE OVER THE MID MS VALLEY WITH
RIDGING NORTH INTO MN/WI. WINDS LIGHTER ACROSS THE REGION TODAY WITH
THE SFC-850MB RIDGE AXIS OVER THE UPPER MIDWEST. MOISTURE GRADUALLY
INCREASING OVER IA/SOUTHERN MN AS LOWER LEVEL FLOW BECOMES MORE WEST
AND SOUTHWEST. WV IMAGERY DEPICTED A SHORTWAVE MOVING SOUTHEAST
ACROSS THE DAKOTAS...WITH INCREASING CLOUDS/FEW SHRA AHEAD OF IT
ACROSS WESTERN MN. EARLY AFTERNOON TEMPS NEAR NORMAL FOR THE FIRST
OF AUGUST.
NO BIG ISSUES NOTED WITH 01.12Z MODEL INITIALIZATIONS. SOLUTIONS
QUITE SIMILAR FOR TONIGHT THRU SUN NIGHT...AND VERY SIMILAR TO THEIR
RUNS OF 31.12Z. THIS AS ONE PIECE OF SHORTWAVE ENERGY DROPS IA/
SOUTHERN MN TONIGHT THEN NORTHERN STREAM ENERGY DROPPING OUT OF MAN/
WESTERN ONT LOWERS HGTS ACROSS THE REGION AS IT PASSES SUN/SUN
NIGHT. WITH THE TIGHT CONSENSUS...SHORT TERM FCST CONFIDENCE REMAINS
GENERALLY GOOD THIS CYCLE.
IN THE SHORT TERM...SHORTWAVE APPROACHING/PASSING ACROSS IA/SOUTHERN
MN TONIGHT SPREADS A ROUND OF LOWER LEVEL THERMO-DYNAMIC FORCING/
LIFT ACROSS THE AREA...AHEAD OF THE SFC-700MB TROUGH/FRONT. MODEL
SOUNDINGS CONTINUE TO SHOW THE BULK OF THE MOISTURE/SATURATION IS AT
OR ABOVE 800MB. MUCAPE VALUES IN THE 500-1500 J/KG RANGE ARE MOSTLY
LIFTING 800-700MB PARCELS...WHERE THE CIN VALUES ARE MORE IN THE 0
TO 25 RANGE. SOUNDING SHOW LIFTING SFC BASED PARCELS TONIGHT WILL
GENERATE SOME CAPE...BUT NOT BEFORE ENCOUNTERING 100-400 J/KG OF CIN
THAT IS 200-300MB DEEP. SFC-850MB LAYER INVOLVEMENT IN CONVECTION
TONIGHT...WHERE MOST OF THE SHEAR LIES...LOOKS MINIMAL WITH MAINLY
ELEVATED SHRA/TSRA AT OR ABOVE 8K-10K FT. BULK SHEAR IN THE
EFFECTIVE 2KM-8KM LAYER MORE IN THE 115-20KT RANGE. GIVEN ALL
THIS...CONFIDENCE IN ANY SEVERE STORM THREAT TONIGHT IS LOW. WILL
MAINTAIN AN ISOLATED SEVERE TSRA MENTION TONIGHT FOR CONTINUITY
SAKE. TONIGHTS ROUND OF CONVECTION IF IT DEVELOPS...AS THERE ARE A
FEW HI-RES/WRF MODELS THAT KEEP THE AREA DRY TONIGHT...WOULD EXIT
THE AREA EARLY SUN MORNING. SFC FRONT WORKS ITS WAY SOUTHEAST ACROSS
THE FCST AREA SUN BUT MODEL SOUNDINGS SHOWING CONSIDERABLE CAPPING/
CIN BETWEEN 900-850MB MUCH OF THE DAY. LOWERED/REMOVED SHRA/TSRA
CHANCES ACROSS MUCH OF THE FCST AREA FOR LATER SUN MORNING.
CONTINUED SHRA/TSRA CHANCES ACROSS MAINLY THE EAST 2/3 OF THE FCST
AREA SUN AFTERNOON WITH THE FRONT DROPPING THRU...EROSION OF THE
CAPPING AFTER 20-21Z AND APPROACH OF THE STRONGER SHORTWAVE FROM
THE NORTH. IF ANY STORMS LATER SUN AFTERNOON INTO SUN EVENING ARE
SFC BASED...0-6KM BULK SHEAR WOULD BE MORE IN THE 35KT RANGE ALONG
WITH MUCAPE IN THE 1.5K TO 3K J/KG RANGE. CANNOT RULE OUT A SEVERE
TSRA OR TWO OVER THE EAST/SOUTH ENDS OF THE FCST AREA LATER SUN
AFTERNOON/EARLY SUN EVENING. FRONT DROPS QUICKLY SOUTH OF THE FCST
AREA SUN EVENING...WITH DRIER HIGH PRESSURE/SUBSIDENCE/LOW LEVEL
COLD ADVECTION SPREADING IN BEHIND IT AND THE MID LEVEL TROUGH AXIS.
USED A BLEND OF GUIDANCE LOWS/HIGHS FOR TONIGHT THRU SUN NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 245 PM CDT SAT AUG 1 2015
FOR MONDAY THRU TUESDAY NIGHT...
MAIN FCST CONCERNS FOR MON THRU TUE NIGHT...TEMPERATURES.
01.12Z MODELS REMAIN IN GOOD AGREEMENT AS THE EAST CAN MID LEVEL LOW
AND TROUGHING OVER THE GREAT LAKES SLOWLY PROGRESS EAST MON THRU TUE
NIGHT. HGTS GRADUALLY RISE THIS PERIOD...WITH THE REGION REMAINING
UNDER NORTHWEST FLOW ALOFT. MODELS IN REASONABLE AGREEMENT ON SOME
SHORTWAVE ENERGY COMING OUT OF THE WEST COAST TROUGHING AND MOVING
INTO THE CENTRAL/NORTHERN PLAINS BY 12Z WED. FCST CONFIDENCE FOR MON
THRU TUE NIGHT IS GOOD THIS CYCLE.
MON THRU TUE NIGHT SHAPING UP TO BE A DRY...QUIET PERIOD WITH TEMPS
A BIT BELOW NORMAL. DRIER CAN HIGH PRESSURE IN THE WAKE OF SUNDAYS
COLD FRONT BUILDS SLOWLY EAST ACROSS THE UPPER MIDWEST MON THRU TUE
NIGHT...UNDER THE SLOWLY RISING HGTS ALOFT. 850MB TEMPS TRENDING TO
BE 0.5 TO 1 STANDARD DEVIATION BELOW NORMAL THRU THE PERIOD. NORMAL
HIGHS FOR THE FIRST WEEK OF AUG ARE IN THE 79F TO 84F RANGE. MODEL/
ENSEMBLE CONSENSUS HIGHS MOSTLY IN THE 75F TO 82F RANGE MON/TUE
LOOKING WELL TRENDED. WITH A DRIER AIRMASS...LIGHT WINDS AND CLEAR/
MOSTLY CLEAR SKIES...MON/TUE NIGHTS FAVORABLE FOR STRONGER
RADIATIONAL COOLING. CONSENSUS LOWS MOSTLY IN THE LOW TO MID 50S
BOTH NIGHTS APPEAR WELL TRENDED FOR NOW. HOWEVER WILL HAVE TO WATCH
THE NORMALLY COOLER/SHELTERED LOCATIONS ALONG/NORTHEAST OF I-94 FOR
SOME LOWS POTENTIALLY DIPPING INTO THE LOW TO MID 40S BOTH NIGHTS.
FOR WEDNESDAY THRU SATURDAY...DAYS 4 TO 7...
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES LATER WED NIGHT
INTO SAT...TEMPERATURES THRU THE PERIOD.
MEDIUM RANGE MODEL RUNS OF 01.00Z AND 01.12Z IN REASONABLE AGREEMENT
ON WED WITH TROUGHING NEAR THE COASTS AND A MID LEVEL RIDGE AXIS
OVER CENTRAL NOAM. PLENTY OF DETAIL DIFFERENCES WITH SHORTWAVE
ENERGY COMING THRU THE RIDGE ON WED. QUITE A BIT OF BETWEEN MODEL
AND RUN-TO-RUN VARIABILITY ON THU AS STRONGER SHORTWAVE ENERGY WOULD
TOP/FLATTEN THE RIDGING AND START TO DROP INTO THE UPPER MIDWEST.
SOME CONSENSUS BETWEEN GFS/ECMWF FOR A STRONGER SHORTWAVE TROUGH TO
MOVE ACROSS THE REGION THU NIGHT/FRI...WEAK SHORTWAVE RIDGING FRI
NIGHT THEN ANOTHER STRONGER WAVE TO TOP THE RIDGE AND DROP SOUTHEAST
INTO THE REGION SAT. GIVEN THE LARGER DETAIL DIFFERENCES WED/THU...
FCST CONFIDENCE IN THE DAY 4-7 PERIOD IS BELOW AVERAGE THIS CYCLE.
ANY SHORTWAVE ENERGY TO APPROACH/MOVE IN WED APPEARS WEAK. A GOOD
MODEL CONSENSUS TO HOLD DRIER SFC HIGH PRESSURE OVER THE UPPER
MIDWEST WED...WITH THE MAIN LOWER LEVEL MOISTURE/CAPE AXIS WELL
WEST/SOUTH OF THE FCST AREA UNTIL LATER WED NIGHT INTO THU. MOISTURE
INCREASES THU...AHEAD OF THE FIRST SHORTWAVE TO TOP THE RIDGE AND
LOW PRESSURE ADVANCING EAST ACROSS THE PLAINS TOWARD/INTO THE
MID/UPPER MS VALLEY. INCREASING SHRA/TSRA CHANCES THU INTO FRI AS
THIS SFC-MID LEVEL TROUGH AXIS WOULD PASS REASONABLE AT THIS POINT.
TIMING DIFFERENCES BY FRI NIGHT/SAT...BUT WITH ANOTHER SHORTWAVE
LOOKING TO TOP THE RIDGE AND LOWER HGTS OVER THE REGION...SMALL
CONSENSUS SHRA/TSRA CHANCES THESE PERIODS OKAY FOR NOW. NORTHWEST
FLOW ALOFT AND/OR MORE CLOUDS /ESPECIALLY THU/FRI/ LOOKING TO KEEP
TEMPS NEAR TO BELOW NORMAL IN THE DAY 4-7 PERIOD. MODEL/ENSEMBLE
CONSENSUS WITH HIGHS/LOWS A FEW DEGREES BELOW NORMAL LOOKS TO HAVE
THEM WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 610 PM CDT SAT AUG 1 2015
STILL CONSIDERABLE UNCERTAINTY ON HOW MUCH CONVECTION IS GOING TO
DEVELOP THIS EVENING AND WHERE. THE LATEST REGIONAL COMPOSITE
SHOWS SOME DEVELOPMENT OCCURRING OVER NORTH CENTRAL SOUTH
DAKOTA...WHICH IS CLOSE TO WHERE SEVERAL OF THE HI-RES MODELS
SUGGESTED THIS DEVELOPMENT WOULD OCCUR. EXPECTING THAT THIS
ACTIVITY SHOULD WORK TO THE SOUTHEAST AND DISSIPATE THROUGH THE
EVENING AS THE NOSE OF THE LOW LEVEL JET BECOMES FOCUSED ON A WARM
FRONT OVER CENTRAL MINNESOTA. ADDITIONAL CONVECTION IS THEN
EXPECTED TO FORM ALONG AND NORTH OF THIS WARM FRONT AND MOVE EAST
INTO NORTHERN WISCONSIN AS THE NOSE OF THE LOW LEVEL JET FOCUSES
ON THIS AREA BY LATE TONIGHT. WITH THIS OUTCOME...ALL OF THE
CONVECTION WOULD STAY TO THE NORTH OF THE TAF SITES. HOWEVER...THE
01.21Z HRRR KEEPS THE DEVELOPING SOUTH DAKOTA CONVECTION GOING AND
BRINGS IT INTO THE AREA LATE THIS EVENING. TO HONOR THIS
SOLUTION...HAVE MAINTAINED THE VCTS MENTION IN BOTH TAF SITES BUT
PUSHED THE TIMING BACK CLOSER TO 06Z. THIS CHANCE SHOULD THEN END
LATE TONIGHT WITH SKIES QUICKLY CLEARING AS MID LEVEL WARM AIR
MOVES IN BEHIND THE WARM FRONT TO FORM A STRONG LOW LEVEL CAP.
FOR SUNDAY AFTERNOON AS A COLD FRONT SLIDES INTO THE AREA...THE
01.18Z NAM SUGGESTS THIS CAP WILL HOLD STRONG WITH THE FRONT
PASSING THROUGH DRY AND WITH VERY LITTLE IF ANY CLOUD COVER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...04
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
610 PM CDT SAT AUG 1 2015
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 245 PM CDT SAT AUG 1 2015
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES TONIGHT INTO SUN
EVENING...ANY SEVERE THREAT TONIGHT AND AGAIN SUN AFTERNOON/EVENING.
DATA ANALYSIS AT 18Z HAD HIGH PRESSURE OVER THE MID MS VALLEY WITH
RIDGING NORTH INTO MN/WI. WINDS LIGHTER ACROSS THE REGION TODAY WITH
THE SFC-850MB RIDGE AXIS OVER THE UPPER MIDWEST. MOISTURE GRADUALLY
INCREASING OVER IA/SOUTHERN MN AS LOWER LEVEL FLOW BECOMES MORE WEST
AND SOUTHWEST. WV IMAGERY DEPICTED A SHORTWAVE MOVING SOUTHEAST
ACROSS THE DAKOTAS...WITH INCREASING CLOUDS/FEW SHRA AHEAD OF IT
ACROSS WESTERN MN. EARLY AFTERNOON TEMPS NEAR NORMAL FOR THE FIRST
OF AUGUST.
NO BIG ISSUES NOTED WITH 01.12Z MODEL INITIALIZATIONS. SOLUTIONS
QUITE SIMILAR FOR TONIGHT THRU SUN NIGHT...AND VERY SIMILAR TO THEIR
RUNS OF 31.12Z. THIS AS ONE PIECE OF SHORTWAVE ENERGY DROPS IA/
SOUTHERN MN TONIGHT THEN NORTHERN STREAM ENERGY DROPPING OUT OF MAN/
WESTERN ONT LOWERS HGTS ACROSS THE REGION AS IT PASSES SUN/SUN
NIGHT. WITH THE TIGHT CONSENSUS...SHORT TERM FCST CONFIDENCE REMAINS
GENERALLY GOOD THIS CYCLE.
IN THE SHORT TERM...SHORTWAVE APPROACHING/PASSING ACROSS IA/SOUTHERN
MN TONIGHT SPREADS A ROUND OF LOWER LEVEL THERMO-DYNAMIC FORCING/
LIFT ACROSS THE AREA...AHEAD OF THE SFC-700MB TROUGH/FRONT. MODEL
SOUNDINGS CONTINUE TO SHOW THE BULK OF THE MOISTURE/SATURATION IS AT
OR ABOVE 800MB. MUCAPE VALUES IN THE 500-1500 J/KG RANGE ARE MOSTLY
LIFTING 800-700MB PARCELS...WHERE THE CIN VALUES ARE MORE IN THE 0
TO 25 RANGE. SOUNDING SHOW LIFTING SFC BASED PARCELS TONIGHT WILL
GENERATE SOME CAPE...BUT NOT BEFORE ENCOUNTERING 100-400 J/KG OF CIN
THAT IS 200-300MB DEEP. SFC-850MB LAYER INVOLVEMENT IN CONVECTION
TONIGHT...WHERE MOST OF THE SHEAR LIES...LOOKS MINIMAL WITH MAINLY
ELEVATED SHRA/TSRA AT OR ABOVE 8K-10K FT. BULK SHEAR IN THE
EFFECTIVE 2KM-8KM LAYER MORE IN THE 115-20KT RANGE. GIVEN ALL
THIS...CONFIDENCE IN ANY SEVERE STORM THREAT TONIGHT IS LOW. WILL
MAINTAIN AN ISOLATED SEVERE TSRA MENTION TONIGHT FOR CONTINUITY
SAKE. TONIGHTS ROUND OF CONVECTION IF IT DEVELOPS...AS THERE ARE A
FEW HI-RES/WRF MODELS THAT KEEP THE AREA DRY TONIGHT...WOULD EXIT
THE AREA EARLY SUN MORNING. SFC FRONT WORKS ITS WAY SOUTHEAST ACROSS
THE FCST AREA SUN BUT MODEL SOUNDINGS SHOWING CONSIDERABLE CAPPING/
CIN BETWEEN 900-850MB MUCH OF THE DAY. LOWERED/REMOVED SHRA/TSRA
CHANCES ACROSS MUCH OF THE FCST AREA FOR LATER SUN MORNING.
CONTINUED SHRA/TSRA CHANCES ACROSS MAINLY THE EAST 2/3 OF THE FCST
AREA SUN AFTERNOON WITH THE FRONT DROPPING THRU...EROSION OF THE
CAPPING AFTER 20-21Z AND APPROACH OF THE STRONGER SHORTWAVE FROM
THE NORTH. IF ANY STORMS LATER SUN AFTERNOON INTO SUN EVENING ARE
SFC BASED...0-6KM BULK SHEAR WOULD BE MORE IN THE 35KT RANGE ALONG
WITH MUCAPE IN THE 1.5K TO 3K J/KG RANGE. CANNOT RULE OUT A SEVERE
TSRA OR TWO OVER THE EAST/SOUTH ENDS OF THE FCST AREA LATER SUN
AFTERNOON/EARLY SUN EVENING. FRONT DROPS QUICKLY SOUTH OF THE FCST
AREA SUN EVENING...WITH DRIER HIGH PRESSURE/SUBSIDENCE/LOW LEVEL
COLD ADVECTION SPREADING IN BEHIND IT AND THE MID LEVEL TROUGH AXIS.
USED A BLEND OF GUIDANCE LOWS/HIGHS FOR TONIGHT THRU SUN NIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 245 PM CDT SAT AUG 1 2015
FOR MONDAY THRU TUESDAY NIGHT...
MAIN FCST CONCERNS FOR MON THRU TUE NIGHT...TEMPERATURES.
01.12Z MODELS REMAIN IN GOOD AGREEMENT AS THE EAST CAN MID LEVEL LOW
AND TROUGHING OVER THE GREAT LAKES SLOWLY PROGRESS EAST MON THRU TUE
NIGHT. HGTS GRADUALLY RISE THIS PERIOD...WITH THE REGION REMAINING
UNDER NORTHWEST FLOW ALOFT. MODELS IN REASONABLE AGREEMENT ON SOME
SHORTWAVE ENERGY COMING OUT OF THE WEST COAST TROUGHING AND MOVING
INTO THE CENTRAL/NORTHERN PLAINS BY 12Z WED. FCST CONFIDENCE FOR MON
THRU TUE NIGHT IS GOOD THIS CYCLE.
MON THRU TUE NIGHT SHAPING UP TO BE A DRY...QUIET PERIOD WITH TEMPS
A BIT BELOW NORMAL. DRIER CAN HIGH PRESSURE IN THE WAKE OF SUNDAYS
COLD FRONT BUILDS SLOWLY EAST ACROSS THE UPPER MIDWEST MON THRU TUE
NIGHT...UNDER THE SLOWLY RISING HGTS ALOFT. 850MB TEMPS TRENDING TO
BE 0.5 TO 1 STANDARD DEVIATION BELOW NORMAL THRU THE PERIOD. NORMAL
HIGHS FOR THE FIRST WEEK OF AUG ARE IN THE 79F TO 84F RANGE. MODEL/
ENSEMBLE CONSENSUS HIGHS MOSTLY IN THE 75F TO 82F RANGE MON/TUE
LOOKING WELL TRENDED. WITH A DRIER AIRMASS...LIGHT WINDS AND CLEAR/
MOSTLY CLEAR SKIES...MON/TUE NIGHTS FAVORABLE FOR STRONGER
RADIATIONAL COOLING. CONSENSUS LOWS MOSTLY IN THE LOW TO MID 50S
BOTH NIGHTS APPEAR WELL TRENDED FOR NOW. HOWEVER WILL HAVE TO WATCH
THE NORMALLY COOLER/SHELTERED LOCATIONS ALONG/NORTHEAST OF I-94 FOR
SOME LOWS POTENTIALLY DIPPING INTO THE LOW TO MID 40S BOTH NIGHTS.
FOR WEDNESDAY THRU SATURDAY...DAYS 4 TO 7...
MAIN FCST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES LATER WED NIGHT
INTO SAT...TEMPERATURES THRU THE PERIOD.
MEDIUM RANGE MODEL RUNS OF 01.00Z AND 01.12Z IN REASONABLE AGREEMENT
ON WED WITH TROUGHING NEAR THE COASTS AND A MID LEVEL RIDGE AXIS
OVER CENTRAL NOAM. PLENTY OF DETAIL DIFFERENCES WITH SHORTWAVE
ENERGY COMING THRU THE RIDGE ON WED. QUITE A BIT OF BETWEEN MODEL
AND RUN-TO-RUN VARIABILITY ON THU AS STRONGER SHORTWAVE ENERGY WOULD
TOP/FLATTEN THE RIDGING AND START TO DROP INTO THE UPPER MIDWEST.
SOME CONSENSUS BETWEEN GFS/ECMWF FOR A STRONGER SHORTWAVE TROUGH TO
MOVE ACROSS THE REGION THU NIGHT/FRI...WEAK SHORTWAVE RIDGING FRI
NIGHT THEN ANOTHER STRONGER WAVE TO TOP THE RIDGE AND DROP SOUTHEAST
INTO THE REGION SAT. GIVEN THE LARGER DETAIL DIFFERENCES WED/THU...
FCST CONFIDENCE IN THE DAY 4-7 PERIOD IS BELOW AVERAGE THIS CYCLE.
ANY SHORTWAVE ENERGY TO APPROACH/MOVE IN WED APPEARS WEAK. A GOOD
MODEL CONSENSUS TO HOLD DRIER SFC HIGH PRESSURE OVER THE UPPER
MIDWEST WED...WITH THE MAIN LOWER LEVEL MOISTURE/CAPE AXIS WELL
WEST/SOUTH OF THE FCST AREA UNTIL LATER WED NIGHT INTO THU. MOISTURE
INCREASES THU...AHEAD OF THE FIRST SHORTWAVE TO TOP THE RIDGE AND
LOW PRESSURE ADVANCING EAST ACROSS THE PLAINS TOWARD/INTO THE
MID/UPPER MS VALLEY. INCREASING SHRA/TSRA CHANCES THU INTO FRI AS
THIS SFC-MID LEVEL TROUGH AXIS WOULD PASS REASONABLE AT THIS POINT.
TIMING DIFFERENCES BY FRI NIGHT/SAT...BUT WITH ANOTHER SHORTWAVE
LOOKING TO TOP THE RIDGE AND LOWER HGTS OVER THE REGION...SMALL
CONSENSUS SHRA/TSRA CHANCES THESE PERIODS OKAY FOR NOW. NORTHWEST
FLOW ALOFT AND/OR MORE CLOUDS /ESPECIALLY THU/FRI/ LOOKING TO KEEP
TEMPS NEAR TO BELOW NORMAL IN THE DAY 4-7 PERIOD. MODEL/ENSEMBLE
CONSENSUS WITH HIGHS/LOWS A FEW DEGREES BELOW NORMAL LOOKS TO HAVE
THEM WELL TRENDED FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 610 PM CDT SAT AUG 1 2015
STILL CONSIDERABLE UNCERTAINTY ON HOW MUCH CONVECTION IS GOING TO
DEVELOP THIS EVENING AND WHERE. THE LATEST REGIONAL COMPOSITE
SHOWS SOME DEVELOPMENT OCCURRING OVER NORTH CENTRAL SOUTH
DAKOTA...WHICH IS CLOSE TO WHERE SEVERAL OF THE HI-RES MODELS
SUGGESTED THIS DEVELOPMENT WOULD OCCUR. EXPECTING THAT THIS
ACTIVITY SHOULD WORK TO THE SOUTHEAST AND DISSIPATE THROUGH THE
EVENING AS THE NOSE OF THE LOW LEVEL JET BECOMES FOCUSED ON A WARM
FRONT OVER CENTRAL MINNESOTA. ADDITIONAL CONVECTION IS THEN
EXPECTED TO FORM ALONG AND NORTH OF THIS WARM FRONT AND MOVE EAST
INTO NORTHERN WISCONSIN AS THE NOSE OF THE LOW LEVEL JET FOCUSES
ON THIS AREA BY LATE TONIGHT. WITH THIS OUTCOME...ALL OF THE
CONVECTION WOULD STAY TO THE NORTH OF THE TAF SITES. HOWEVER...THE
01.21Z HRRR KEEPS THE DEVELOPING SOUTH DAKOTA CONVECTION GOING AND
BRINGS IT INTO THE AREA LATE THIS EVENING. TO HONOR THIS
SOLUTION...HAVE MAINTAINED THE VCTS MENTION IN BOTH TAF SITES BUT
PUSHED THE TIMING BACK CLOSER TO 06Z. THIS CHANCE SHOULD THEN END
LATE TONIGHT WITH SKIES QUICKLY CLEARING AS MID LEVEL WARM AIR
MOVES IN BEHIND THE WARM FRONT TO FORM A STRONG LOW LEVEL CAP.
FOR SUNDAY AFTERNOON AS A COLD FRONT SLIDES INTO THE AREA...THE
01.18Z NAM SUGGESTS THIS CAP WILL HOLD STRONG WITH THE FRONT
PASSING THROUGH DRY AND WITH VERY LITTLE IF ANY CLOUD COVER.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
343 PM CDT FRI JUL 31 2015
.SHORT TERM...TONIGHT THROUGH MONDAY.
TONIGHT AND SATURDAY - CONFIDENCE...MEDIUM
STRONG NW MID LEVEL FLOW PERSISTS WITH PRIMARY SHORTWAVE OF NOTE
TRAVERSING THROUGH LAKE SUPERIOR INTO LWR MI REGION TONIGHT.
NAM/ARW/NMM/HRRR ALL SHOWING SOME LIGHT PRECIP DEVELOPING LATER IN
THE NIGHT DUE TO LOW LEVEL CONVERGENCE ASSOCIATED WITH SURFACE/850
TROUGH. NOT MUCH SHOWING ON THIS UPSTREAM AND WITH OVERALL DRY AIRMASS
AND POOR TIMING THERMODYNAMICALLY CONFIDENCE NOT GREAT IN MUCH IF
ANYTHING EVOLVING. RAP SOUNDINGS ARE ALL VERY DRY WITH LITTLE IN THE
WAY OF ELEVATED CAPE. HOWEVER NAM/GFS AND HRRR SOUNDINGS SHOW A LITTLE
BETTER MID LEVEL MOISTENING WITH SOME ELEVATED CAPE. CONSENSUS OF MOS
POPS ARE IN THE SINGLE DIGITS. WILL CARRY A A SMALL AREA OF SLGT POPS
FROM LATE TONIGHT INTO EARLY SATURDAY ACROSS PORTIONS OF WRN AND SRN
CWA. FROM LATER IN THE MORNING INTO THE AFTERNOON SURFACE/850 RIDGING
WILL TAKE HOLD WITH A MORE RELAXED PRESSURE GRADIENT IN PLACE TO
SUPPORT A LIGHTER WIND REGIME. 925 TEMPS AVERAGE 22-23C SO EXPECTING
HIGHS BACK INTO THE 80S.
SATURDAY NIGHT...FORECAST CONFIDENCE MEDIUM
WEAK SHORT WAVE APPROACHES SATURDAY NIGHT...CENTERED OVER CWA AT 12Z
SUNDAY...MOVING EAST OF AREA BY 18Z....WITH STRONGER SHORT WAVE
TROUGH MOVING INTO NORTH DAKOTA BY 12Z SUNDAY. LOW-LEVEL THETA-E
ADVECTION MAX CROSSES CWA BETWEEN 03Z AND 06Z SUNDAY...HOWEVER
STRONGER OMEGA TIED WITH STRONGEST FRONTOGENETIC RESPONSE OVER NE WI
TO FOCUSED WARM AIR ADVECTION WITH THE 35-40 KT LOW-LEVEL JET MAX
AHEAD OF STRONG WAVE TO THE NORTHWEST. THIS BETTER FORCING ON THE
NOSE OF THE LLJ SHIFTS EAST AS THE AXIS OF THE LLJ DROPS SOUTH
THROUGH THE STATE OVERNIGHT...BRUSHING THE EASTERN CWA. WILL KEEP
HIGH CHANCE POPS GOING FOR AFTER MIDNIGHT...WITH LATER SHIFTS
POSSIBLY ABLE TO RAISE WITH BETTER CLARITY FROM LATER MODEL RUNS.
SUNDAY...FORECAST CONFIDENCE MEDIUM
PERSISTENT LOW-LEVEL FLOW CONTINUES OVER AREA AHEAD OF SECOND...
STRONGER SHORT WAVE AND ASSOCIATED SURFACE LOW AND COLD FRONT
DIPPING INTO NRN WI BY 00Z MONDAY. PLENTY OF FORCING ALONG/AHEAD OF
850 MB TROUGH AXIS AND SURFACE FRONT BUT STRONG AND DEEP CAPPING
NOTED ON FORECAST SOUNDINGS ESPECIALLY OVER THE WESTERN CWA WITH
PERSISTENT WARM AIR ADVECTION. LESS OF A CAP OVER EASTERN AREAS WITH
HIGHER PW/S. WILL HAVE LOWER CHANCE POPS IN THE MORNING FOR
DEPARTING WARM-AIR ADVECTION FORCING...AND KEEP THEM IN THE
AFTERNOON FOR INSTABILITY AND APPROACHING LOW-LEVEL FORCING WITH THE
LOW.
SUNDAY NIGHT...FORECAST CONFIDENCE MEDIUM
SECOND STRONGER SHORT WAVE DROPS IN SUNDAY NIGHT PUSHING LOW AND
COLD FRONT THROUGH THE SOUTHERN HALF OF THE STATE. BETTER CHANCES
FOR SHOWERS AND STORMS IN THE EVENING BEFORE FRONT DROPS SOUTH IN BY
06Z...WITH CAP ERODING AS MID-LEVELS COOL. KEPT A COLLABORATIVE
SLIGHT CHANCE AFTER 06Z...BUT LOOKS AS IF PCPN WILL BE SOUTH OF AREA
BY 06Z.
MONDAY...FORECAST CONFIDENCE HIGH
DRY WEATHER WITH HIGH PRESSURE BUILDING IN WITH SLIGHTLY COOLER
TEMPERATURES...BUT WITH DEW POINTS FALLING INTO THE 50S WITH DEEP
MIXING.
.LONG TERM...MONDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE LOW
MODELS DIFFER WITH LOCATION OF STATIONARY FRONT TO THE SOUTH AND HOW
FAR NORTH PRECIPITATION SHIELD WILL REACH AS WAVE MOVES ALONG
STALLED BOUNDARY TUESDAY AND WEDNESDAY. MOST MODELS KEEP PCPN SOUTH
OF STATE TUESDAY AND SPLIT ON HOW FAR NORTH TO BRING COVERAGE
WEDNESDAY. WITH DRY BROAD HIGH IN PLACE OVER WESTERN GREAT LAKES
WILL GO WITH CONSERVATIVE CONSENSUS SLIGHT CHANCE POPS FOR
WEDNESDAY...WITH CHANCE POPS LIMITED TO THE IL BORDER. MORE
PROGRESSIVE GFS BRINGS A STRONGER LOW ACROSS OR THURSDAY
AFTERNOON/NIGHT WITH ECMWF KEEPING AREA DRY INTO FRIDAY NIGHT.
RESULTING BLEND BRINGS SLIGHT/LOW CHANCES FOR SHOWERS/STORMS FOR THE
END OF THE EXTENDED...THOUGH NOT EVERY PERIOD WILL EVENTUALLY HAVE
PRECIPITATION. AFTER HIGHS IN THE LOW 80S TUESDAY...TEMPERATURES
WILL COOL INTO THE 70S FOR THE REST OF THE EXTENDED...WITH LOWS
MAINLY IN THE 50S.
&&
.AVIATION/00Z TAFS/...WNW WINDS EXPECTED TO EASE A BIT THIS EVENING
WITH LOSS OF HEATING. NAM/LATEST HRRR/ARW/NMM WANT TO GENERATE SOME
LIGHT PRECIP INTO SC WI LATE TNGT/ERLY SAT BUT WILL LEAVE MENTION
OUT OF TAF AT THIS TIME. WITH SURFACE/850 RIDGE DRAWING CLOSER ON
SATURDAY EXPECT AN OVERALL LIGHTER WIND REGIME.
&&
.MARINE...A SMALL CRAFT ADVISORY IS IN EFFECT THROUGH THE AFTERNOON
DUE TO GUSTY WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS. A FEW GUSTS
MAY REACH 30 KNOTS AT TIMES. WINDS WILL DIMINISH EARLY THIS
EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TONIGHT/SATURDAY AND AVIATION/MARINE...COLLAR
SATURDAY NIGHT THROUGH FRIDAY...REM
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1021 AM CDT FRI JUL 31 2015
.AVIATION/18Z TAFS/...WNW WINDS WILL CONTINUE TO RAMP UP WITH
DECENT MIXING BUT EXPECT SOME DROPOFF THIS EVENING WITH LOSS OF
HEATING. NAM/LATEST HRRR WANT TO GENERATE SOME LIGHT PRECIP INTO
SC WI LATE TNGT BUT WILL LEAVE MENTION OUT OF TAF AT THIS TIME.
WITH SURFACE/850 RIDGE DRAWING CLOSER ON SATURDAY EXPECT AN
OVERALL LIGHTER WIND REGIME.
PC
&&
.PREV DISCUSSION... /ISSUED 312 AM CDT FRI JUL 31 2015/
TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH.
IN THE VERY EARLY TERM...AROUND OR JUST BEFORE 7 AM THIS
MORNING...THERE IS A WEAK SURFACE TROF PASSING THROUGH COUPLED WITH
A MID LEVEL TROF UP ABOVE. HIGHER DEWPOINTS ARE SNEAKING UP JUST
AHEAD OF THE FRONT AND SOME OF THE HI RES MODELS QUICKLY GENERATE A
FEW SHOWERS ACROSS SOUTH CENTRAL AREAS...THEN JUST AS QUICKLY WIPE
THEM OUT AS THEY MOVE SOUTHEAST. THERE ISN/T MUCH ON SATELLITE RIGHT
NOW...JUST A FEW CLOUDS OVER SOUTHEAST MN. SO CONFIDENCE THIS IS
GOING TO HAPPEN IS VERY LOW. WILL BE KEEPING AN EYE ON IT THOUGH.
OTHERWISE...LOOK FOR A VERY SIMILAR DAY TO THE LAST COUPLE. PLENTY
OF SUNSHINE WITH VERY STEEP LOW LEVEL LAPSE RATES WITH DEEP MIXING.
TEMPS WILL BE A FEW DEGREES COOLER THAN YESTERDAY...BUT STILL WARM.
DEW POINTS WILL MIX OUT ONCE AGAIN...PRODUCING LOW HUMIDITY.
QUIET AND PLEASANTLY COOL TONIGHT.
SATURDAY AND SUNDAY...FORECAST CONFIDENCE...MEDIUM
HIGH PRESSURE WILL SLIDE SOUTHWARD ON SATURDAY...BUT SHOULD HAVE
ENOUGH OF A REMAINING INFLUENCE TO KEEP IT DRY THROUGH THE DAYTIME
HOURS. SHOULD SEE A GOOD AMOUNT OF SUNSHINE...WITH HIGHS IN THE 80S
ONCE AGAIN.
LOOKS LIKE A DECENT CHANCE FOR STORMS AT TIMES SATURDAY NIGHT
THROUGH SUNDAY NIGHT. FIRST ROUND SATURDAY EVENING AND OVERNIGHT IS
EXPECTED TO COME AS LOW LEVEL JET STRENGTHENS AND MOVES OVERHEAD
AHEAD OF AN APPROACHING SHORTWAVE. SPC IS HIGHLIGHTING THE SOUTHWEST
HALF OF THE FORECAST ARE WITH A MARGINAL TO SLIGHT RISK OF SEVERE
STORMS. NOT SURPRISING GIVEN BEST FORECAST INSTABILITY IN THE
SOUTHWEST...WITH 30-40 KNOTS OF BULK SHEAR ACROSS THE FORECAST AREA.
THINKING THUNDERSTORM COMPLEX WILL DEVELOP UPSTREAM AND THEN ROLL
INTO THE FORECAST AREA.
SUNDAY IS A BIT OF A QUESTION MARK WITH PRECIP CHANCES. MODELS
SHOWING A WEAK WAVE DURING THE DAY WHICH COULD TRIGGER
STORMS...DEPENDING ON HOW QUICKLY THINGS RECOVER AFTER THE OVERNIGHT
ROUND OF STORMS. CURRENTLY...MODELS SHOWING QUITE A BIT OF CAPE
BY AFTERNOON. BETTER CHANCE WILL PROBABLY BE IN THE EVENING HOURS
AS A COLD FRONT ADVANCES INTO THE AREA. GIVEN
SHEAR...INSTABILITY...AND CURRENT TIMING OF FRONT...THINKING SOME
STRONG TO SEVERE STORMS POSSIBLE ONCE AGAIN.
TEMPS FOR SUNDAY ARE A HEADACHE...WITH MODELS ALL OVER THE PLACE.
WILL DEPEND ON TIMING OF SHORTWAVES AND PRECIP...AND RESULTANT CLOUD
COVER DURING THE DAY. PRETTY GOOD SPREAD IN TEMPS ALOFT BETWEEN
REALLY WARM NAM/GFS SOLUTIONS VS SOMEWHAT COOLER ECMWF. STUCK CLOSE
TO CONSENSUS BLEND OF SOLUTIONS GIVEN UNCERTAINTY.
MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE...MEDIUM
COULD SEE A LINGERING SHOWER OR TWO MONDAY MORNING...BUT OTHERWISE
IT LOOKS DRY AS HIGH PRESSURE BEGINS TO BUILD IN FROM THE
NORTHWEST. SHOULD BE DRY THEN TUESDAY UNDER THE HIGH...WITH A
COUPLE SHOWERS POSSIBLY CLIPPING THE SOUTHWEST WEDNESDAY AS A WEAK
WAVE SLIDES THROUGH. HAVE LOW POPS IN FOR THURSDAY AS ANOTHER WAVE
TRAVERSES THE AREA.
HIGH TEMPS MON/TUE LOOK TO BE WITHIN A COUPLE DEGREES OF
NORMAL...COOLING A FEW DEGREES FOR WED/THU UNDER PERSISTENT
NORTHWEST FLOW ALOFT.
AVIATION/12Z TAFS/...
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD. THERE IS A VERY
SMALL CHANCE OF A SHOWER AT KMSN BEFORE 12Z THIS MORNING...
ASSOCIATED WITH THE PASSING OF A WEAK SURFACE TROUGH. WINDS WILL
AGAIN BE GUSTY OUT OF THE WEST TO NORTHWEST FROM LATE MORNING
THROUGH THE AFTERNOON...DIMINISHING QUICKLY BY EARLY EVENING.
MARINE...
A SMALL CRAFT ADVISORY IS IN EFFECT FROM LATE MORNING THROUGH THE
AFTERNOON DUE TO GUSTY WEST TO NORTHWEST WINDS OF 15 TO 25 KNOTS.
WINDS WILL DIMINISH QUICKLY EARLY THIS EVENING.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM CDT THIS EVENING FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...DAVIS
SATURDAY THROUGH THURSDAY...DDV
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1140 PM CDT THU JUL 30 2015
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SYNOPSIS...
ISSUED AT 227 PM CDT THU JUL 30 2015
SEASONABLY WARM TEMPERATURES EXPECTED THROUGH THE WEEKEND.
THE MAIN BAND OF WESTERLIES IS CURRENTLY ACRS SRN CANADA AND THE
NRN CONUS...HAS LIMITED AMPLITUDE...AND HAS A RIDGE OVER THE W AND
A TROF OVER THE HUDSON BAY RGN. THE MAIN CHG DURING THE FCST
PERIOD WL BE A SLOW AND GRADUAL INCREASE IN AMPLITUDE...WITH THE
UPR TROF EXPANDING SWD. THAT WL TILT THE UPR FLOW INTO THE FCST
AREA MORE NWLY WITH TIME.
TEMPERATURES WILL START OUT WARM...WITH DAYTIME HIGHS THROUGH THE
WEEKEND 4-8F DEG ABV NORMAL. BY EARLY NEXT WK THE UPR FLOW SHOULD
TILT NW ENOUGH TO BRING COOLER AIR FM CANADA INTO THE RGN...LIKELY
DROPPING TEMPS TO A LITTLE BLO NORMAL BY LATE IN THE PERIOD. PCPN
CHCS WILL BE LIMITED SINCE THE VERY HUMID AIR WL REMAIN TO OUR
S...AND THE BEST DYNAMICS WITH THE UPR TROF WL STAY N. ALTHOUGH
ALL IT TAKES AT THIS TIME OF YEAR IS ONE CONVECTIVE EVENT TO
SUPPLY A NORMAL WEEKS WORTH OF PCPN...IT SEEMS LIKELY THAT MOST
AREAS WL END UP RECEIVING BLO NORMAL PCPN FOR THE PERIOD.
&&
.SHORT TERM...TONIGHT AND FRIDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
MILD TEMPS AND DEWPOINTS IN THE LOWER 50S MADE FOR PLEASANT
CONDITIONS ACROSS NORTHEAST WISCONSIN LATE THIS AFTERNOON.
HOWEVER...19Z WATER VAPOR SHOWED A SHORTWAVE TRACKING THROUGH NE
MINNESOTA AND HEADING FOR NORTHERN WISCONSIN. THIS FEATURE HAS
ALREADY KICKED OFF SCATTERED STORMS THAT WERE MOVING THROUGH NW
WISCONSIN. WITH SOME INSTABILITY IN NORTH CENTRAL WISCONSIN...AND
LAPSE RATES OF 6-7K/KM...THESE STORMS SHOULD MAINTAIN THEMSELVES
THIS AFTERNOON AS THE SHORTWAVE SWINGS THROUGH. NOTHING SEVERE IS
EXPECTED AS CAPES ARE ONLY 500J/KG AT BEST...BUT WITH DRY AIR
ALOFT AND RAP SOUNDINGS SHOWING INVERTED-V-LIKE SIGNATURES...GUSTY
WINDS AND BRIEF HEAVY RAIN IS POSSIBLE THROUGH EARLY THIS EVENING
TO THE NORTH.
ANY LINGERING SHOWERS AND THUNDERSTORMS THIS EVENING SHOULD
QUICKLY DISSIPATE AFTER SUNSET. CLEAR SKIES SHOULD PREVAIL UNTIL
ABOUT MIDNIGHT AS A WEAK FRONT PUSHES THROUGH AND SCATTERED CLOUD
COVER DEVELOPS...WITH BROKEN CLOUDS TO THE NORTHAS BETTER QG
FORCING GIVES SOME ADDED LIFT.WITH VERY LITTLE CHANGE TO THE
OVERALL WEATHER PATTERN...STAYED CLOSE TO LAST NIGHTS LOW
TEMPERATURES WITH A HINT OF THE BEST PERFORMING GUIDANCE THROWN
IN.
FRIDAYS SET UP LOOKS A LOT SIMILAR TO WHAT WE HAD THIS AFTERNOON.
SUNNY AND DRY TO START THE DAY...WITH SOME FAIR WEATHER CU IN THE
AFTERNOON. ANOTHER WEAK SHORTWAVE WILL BE DROPPING THROUGH THE
MEAN FLOW WHICH COULD KICK OFF A FEW SHOWERS TO THE NORTH. WITH NE
WI SITTING ON THE ANTICYCLONIC SIDE OF A BROAD UPPER LEVEL...HAVE
DOUBTS SHOWERS WILL EVEN DEVELOP. FRIDAYS SHORTWAVE WILL NOT BE AS
DEFINED TODAYS WITH LITTLE TO NO ADDED INSTABILITY. HOWEVER
HIGH-RES MODELS CONTINUE TO SHOW ISOLATED PCPN DEVELOPING IN
RESPONSE TO THE LFQ OF A STRONG 300MB JETSTREAK BRUSHING NORTHERN
WISCONSIN. KEPT SLIGHT CHC POPS FRI AFTERNOON...THOUGH CONFINED
PCPN TO ONLY THE FAR NORTH. HIGHS TOMORROW WILL BE A DEGREE OR
TWO COOLER THAN TODAY...WITH CONTINUED BREEZY WEST WINDS THROUGH
NOT AS HIGH AS WE SAW TODAY.
.LONG TERM...FRIDAY NIGHT THROUGH THURSDAY
ISSUED AT 227 PM CDT THU JUL 30 2015
DAYTIME TEMPS WL CONT ABV NORMAL FOR A FEW DAYS...THEN EVENTUALLY
COOL AS THE UPR FLOW TILTS NWLY. STAYED CLOSE TO A BLEND OF THE
TOP PERFORMING GUIDANCE PRODUCTS.
HARD TO GET A HANDLE ON SPECIFICS OF THE PCPN FCST GIVEN THE
PATTERN. PCPN CHCS WL BE TIED TO SML SCALE SHRTWVS ROUNDING THE
BASE OF SLOWLY STRENGTHENING LNGWV TROF. CURRENT OP MODEL SUITE
NOT VERY ENCOURAGING FOR THE PCPN WE/VE BEEN CARRYING FOR SAT
NGT...WITH MANY OF THE MODELS NOW TAKING THAT THROUGH TO THE S OF
THE FCST AREA. LATE SUN/SUN NGT LOOK BETTER FOR PCPN AT THIS
POINT. BUT THEN AGAIN IN A PATTERN LIKE THIS...THINGS COULD LOOK
TOTALLY DIFFERENT TOMORROW. STUCK WITH CHC POPS FOR MOST AREAS FOR
SAT NGT...AND AGAIN ON SUN NGT.
NO SIG CHGS MADE TO THE EXTENDED FCST INITIALIZATION GRIDS BASED
ON A BROAD BLEND OF GUIDANCE PRODUCTS.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1139 PM CDT THU JUL 30 2015
EXPECT MOSTLY VFR CONDITIONS THROUGH FRIDAY EVENING. SCATTERED
SHOWERS IN CYCLONIC FLOW ACROSS NORTHEAST MINNESOTA AND WESTERN
ONTARIO COULD IMPACT FAR NORTHERN WISCONSIN BUT THINK THAT THERE
WILL BE LITTLE OR NOTHING ON THE WISCONSIN SIDE OF THE BORDER.
VFR CIGS WILL PROBABLY DEVELOP ACROSS NORTHERN WISCONSIN ALONG
WITH ISOLATED/SCATTERED SHOWERS...BUT THE ODDS OF ANY OF THE
SHOWERS IMPACTING THE TAF SITES SEEM LOW ENOUGH TO LEAVE THEM OUT
OF THE TAFS. SHOWERS AND CLOUDS SHOULD DIMINISH AROUND SUNSET ONCE
AGAIN.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS.......SKOWRONSKI
SHORT TERM.....ALLEN
LONG TERM......SKOWRONSKI
AVIATION.......MG
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
244 AM MST SUN AUG 2 2015
.SYNOPSIS...
CONSIDERABLE DRYING OCCURS STARTING TODAY AND INTO THE MIDDLE OF
NEXT WEEK WITH STORM CHANCES CONFINED TO THE HIGHER TERRAIN EAST OF
PHOENIX. TEMPERATURES WILL GRADUALLY WARM AND WILL HOVER NEAR NORMAL
OR SLIGHTLY ABOVE THROUGH NEXT WEEK.
&&
.DISCUSSION...
PRETTY QUIET RADAR EARLY THIS MORNING SAVE FOR A SWATH OF SHOWERS AND
ISOLATED THUNDERSTORMS MOVING INTO NAVAJO AND APACHE COUNTIES. FAIRLY
WEEK SOUTH-SOUTHWEST STEERING FLOW THROUGH A MIXED 850-300MB LAYER
OF 10-15 KTS HAS ALLOWED FOR SUFFICIENT RAINFALL AMOUNTS TO
ACCUMULATE ACROSS THE HIGHER ELEVATIONS OF GILA COUNTY THIS EVENING.
MOST OF THE FOCUS OF MONSOON ACTIVITY WAS ACROSS EASTERN PIMA...GILA
AND GRAHAM COUNTIES SATURDAY EVENING. PER CURRENT SATELLITE IMAGERY A
TONGUE OF DRY AIR IS INFILTRATING SOUTH-CENTRAL ARIZONA MOVING THE
DRY AIRMASS IN FROM THE WEST AND KICKING THE MOISTURE OUT THE DOOR TO
THE EAST. AN UPPER LEVEL SHORTWAVE TROUGH IS THE CULPRIT PUSHING IN
FROM THE WEST BRINGING SOUTHERLY FLOW INTO THE DESERT SOUTHWEST ALONG
WITH DRIER AIR /06Z SUNDAY MIXING RATIOS NEARLY 10 G/KG LESS THAN 24
HOURS AGO/. A BROAD REGION OF DIFFLUENCE STILL RESIDES ACROSS WESTERN
ARIZONA THROUGH EAST CENTRAL NEW MEXICO ALONG THE MOGOLLON RIM...AND
AS EXPECTED THIS WOULD BE THE REGION OF FAVORABLE STORM ACTIVITY
TODAY DURING THIS TRANSITION PERIOD. CURRENT MESOSCALE HIGH RES MODEL
THAT IS IN GOOD AGREEMENT APPEARS TO BE THE HRRR FOR TODAY`S
ACTIVITY.
PER LATEST GFS AND ECMWF...AMONG THEIR ENSEMBLE COUNTERPARTS ARE SLOW
TO MOVE A CUT OFF LOW FORMING IN THE EASTERN PACIFIC TO THE EAST OVER
THE NEXT 5-6 DAYS. THIS WILL ALLOW THE RIDGE OF HIGH PRESSURE TO
FLOAT TO THE WEST AND FLATTEN OUT...WITH A WEAK SOUTHWESTERLY
STEERING FLOW SETTLING IN THROUGH MOST OF THE UPCOMING WEEK. AN
OPTIMUM TIME FOR TEMPERATURES TO GRADUALLY RISE EVEN IF SLIGHTLY
ABOVE SEASONAL AVERAGE...THOUGH AT THIS TIME NONE OF THE GUIDANCE
BRINGS TEMPERATURES TO THE 110 DEGREE MARK FOR PHOENIX BUT THERE ARE
A FEW DAYS WITH 110 OR GREATER OUT ALONG THE LOWER COLORADO
RIVER...GENERALLY A WARMER LOCALE. ALL THIS BEING SAID...STORM
CHANCES OVER THE NEXT 5-6 DAYS ARE SUBSTANTIALLY LESS THAN THE
PREVIOUS DAYS ACROSS THE LOWER DESERTS. A SLIGHT CHANCE WILL BE KEPT
FOR HIGHER ELEVATIONS NORTH AND EAST OF PHOENIX DUE TO THE NATURE OF
MOUNTAIN ACTIVITY. THE NEXT FLOW REVERSAL APPEARS TO SHAPE UP BY LATE
WEEK INTO NEXT WEEKEND AS MOISTURE MAKES A RETURN APPEARANCE AND WIND
FLOW RETURNS TO A SOUTH-SOUTHEASTERLY DIRECTION.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
DRY SOUTHWESTERLY FLOW ALOFT IS EXPECTED TO REDUCE CLOUD COVERAGE
INTO THE CLR-FEW RANGE AT ALL OF THE TAF SITES BY SUN MORNING...WITH
BASES REMAINING MAINLY AOA 10K FEET...WITH THUNDERSTORM DEVELOPMENT
REMAINING WELL OFF TO THE EAST OF THE GREATER PHX AREA ON SUNDAY
AFTERNOON. WINDS TO MAINLY FOLLOW TYPICAL DIURNAL TRENDS THROUGH THE
TAF PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...DRIER AND STABLE WESTERLY FLOW ALOFT WILL
PRODUCE PARTLY CLOUDY SKIES TUESDAY AND WEDNESDAY...WITH LOWER
MINIMUM RELATIVE HUMIDITY GENERALLY IN THE 10 TO 15 PERCENT RANGE.
MOISTURE WILL GRADUALLY INCREASE OVER SOUTHWEST AND SOUTH CENTRAL
ARIZONA THURSDAY THROUGH SATURDAY...INTO THE 15 TO 25 PERCENT
RANGE...WITH A SLIGHT CHANCE OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS 10
TO 15 MPH. FAIR RECOVERY AT NIGHT.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...DEWEY
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
1030 PM MST SAT AUG 1 2015
.UPDATE...AVIATION DISCUSSION.
&&
.SYNOPSIS...
LINGERING STORM CHANCES THE REST OF TODAY WILL MAINLY AFFECT AREAS
ACROSS HIGHER TERRAIN AREAS OF CENTRAL AND EASTERN ARIZONA WITH A
SLIGHT CHANCE OF A FEW STORMS OVER THE LOWER DESERTS. CONSIDERABLE
DRYING OCCURS STARTING SUNDAY AND INTO THE MIDDLE OF NEXT WEEK WITH
STORM CHANCES CONFINED TO THE HIGHER TERRAIN EAST OF PHOENIX.
TEMPERATURES WILL HOVER NEAR NORMAL OR SLIGHTLY ABOVE THROUGH NEXT
WEEK.
&&
.DISCUSSION... A MUCH QUIETER AFTERNOON/EVENING TODAY THAN WHAT WE
SAW YESTERDAY...ESPECIALLY ACROSS THE LOWER ELEVATIONS OF SOUTH-
CENTRAL AZ. DRY AIR THAT IS BEING PULLED NORTHWARD AHEAD OF AN UPPER
TROF THAT IS APPROACHING THE WEST COAST HAS NOW MOVED INTO SE CA AND
THE WESTERN 1/2 OF ARIZONA. THIS DRY AIR HAS PRETTY MUCH SHUT
CONVECTIVE ACTIVITY DOWN AND PUSHED SFC DEWPOINTS DOWN INTO THE
50S ACROSS THE WESTERN 3/4 OF OUR CWA THIS AFTERNOON.
AHEAD OF THIS DRY SURGE...THUNDERSTORMS HAVE ONCE AGAIN DEVELOPED
THIS AFTERNOON ACROSS SOUTHER GILA COUNTY...WHERE DEWPOINTS ARE
STILL WELL UP IN THE 60S UNDER THE MAIN MONSOON MOISTURE PLUME AND
CONTINUED DIFFLUENCE ALOFT. THIS TS ACTIVITY IS NOW BEGINNING TO
SLOWLY DIMINISH AND SHIFT OFF TO THE NORTH THIS EVENING AS THE
MOISTURE PLUME CONTINUES TO SHIFT OFF SLOWLY TO THE EAST...WITH THE
LATEST HRRR HIGH-RES MODEL RUN INDICATING THAT ANY REMAINING
CONVECTIVE ACTIVITY TO END BY MIDNIGHT TONIGHT. TOMORROW STILL LOOKS
LIKE IT WILL BE THE 1ST IN A SERIES OF VERY QUIET DAYS AS DRY AIR
MAKES ITS WAY ACROSS ALL OF AZ. AS FAR AS THE SHORT-TERM GRIDDED AND
ZONE FORECASTS ARE CONCERNED...HAVE LOWERED POPS FOR THE REST OF
THIS EVENING AND TONIGHT INTO THE SINGLE-DIGIT RANGE ACROSS THE
LOWER DESERTS OF SOUTH-CENTRAL AZ AND HAVE MADE SOME MINOR EDITS TO
THE SHORT-TERM TEMPERATURE/DEWPOINT GRIDS TO BETTER REFLECT CURRENT
TRENDS.
&&
.DISCUSSION...
SO FAR THIS AFTERNOON WE HAVE LITTLE SHOWER OR THUNDERSTORM ACTIVITY
AS THE ATMOSPHERE JUST HAS NOT RECOVERED. SKIES HAVE REMAINED MOSTLY
CLEAR SO SUNSHINE HAS NOT BEEN AN ISSUE...BUT SURFACE TEMPERATURES
ARE STILL SOMEWHAT COOL FOR THIS TIME OF DAY AND GENERALLY 5-8
DEGREES COOLER THAN YESTERDAY. MESOSCALE ANALYSIS DOES SHOW AMPLE
MIXED LAYER CAPE ACROSS SOUTH-CENTRAL AND SOUTHEAST ARIZONA ALONG
WITH BROAD DIFFLUENCE OVER MUCH OF ARIZONA. STILL EXPECTING MORE
THUNDERSTORM DEVELOPMENT THROUGH THE REST OF THIS AFTERNOON...BUT
COVERAGE WILL LIKELY BE LIMITED TO MOSTLY HIGHER TERRAIN AREAS. HAVE
LOWERED POPS OVER THE LOWER DESERTS INTO THE SLIGHT CHANCE CATEGORY
DUE TO THE POOR CONVECTIVE START TO THE AFTERNOON...BUT WE SHOULD
STILL GET A FEW STORMS IN THE DESERTS BY THE END OF THE DAY. THERE IS
SOME POTENTIAL FOR SOME STRONG DOWNDRAFT WINDS WITH ANY STRONGER
STORMS...BUT WITH MORE MOIST AIR IN THE BOUNDARY LAYER...OUTFLOW
INTERACTIONS SHOULD BE LESS ACTIVE THAN YESTERDAY.
WATER VAPOR IMAGERY SHOWS DRY AIR QUICKLY MOVING NORTHWARD THROUGH
THE BAJA AREA INTO NORTHERN MEXICO AND MODELS SHOW THIS DRY AIR
WORKING ACROSS ARIZONA STARTING TONIGHT AND OVERTAKING ALL OF THE
STATE BY SUNDAY NIGHT. LINGERING LOWER LEVEL MOISTURE WILL ALLOW FOR
SOME HIGHER TERRAIN SHOWERS AND THUNDERSTORMS...BUT LITTLE TO NO
CHANCE OF ANY ACTIVITY OVER THE LOWER DESERTS. THIS DRY AIR WILL
BASICALLY END OUR STORM CHANCES FOR A FEW DAYS EARLY THIS
WEEK...WHILE TEMPERATURES START TO WARM UP. HIGHS ACROSS OUR
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA DESERTS WILL LIKELY BREAK
110 DEGREES SUNDAY THROUGH WEDNESDAY. SOUTH-CENTRAL ARIZONA DESERT
TEMPERATURES WILL PEAK ON MONDAY OR TUESDAY...BUT FALL SHORT OF
HITTING 110 DEGREES.
THE SUBTROPICAL HIGH POSITIONED OVER THE DESERT SOUTHWEST FOR MONDAY
AND TUESDAY IS FORECAST TO SHIFT EASTWARD INTO NEW MEXICO SOMETIME
WEDNESDAY AND THURSDAY AND REDIRECTING OUR FLOW OUT OF THE SOUTHEAST.
THIS WILL BRING A RETURN TO AT LEAST SOME LIMITED MONSOONAL MOISTURE
AND CHANCES FOR SHOWERS AND THUNDERSTORMS OVER MAINLY THE EASTERN
HALF OF ARIZONA.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
DRY SOUTHWESTERLY FLOW ALOFT IS EXPECTED TO REDUCE CLOUD COVERAGE
INTO THE CLR-FEW RANGE AT ALL OF THE TAF SITES BY SUN MORNING...WITH
BASES REMAINING MAINLY AOA 10K FEET...WITH THUNDERSTORM DEVELOPMENT
REMAINING WELL OFF TO THE EAST OF THE GREATER PHX AREA ON SUNDAY
AFTERNOON. WINDS TO MAINLY FOLLOW TYPICAL DIURNAL TRENDS THROUGH THE
TAF PERIOD.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...DRIER AND STABLE WESTERLY FLOW ALOFT WILL
PRODUCE PARTLY CLOUDY SKIES TUESDAY AND WEDNESDAY...WITH LOWER
MINIMUM RELATIVE HUMIDITY GENERALLY IN THE 10 TO 15 PERCENT RANGE.
MOISTURE WILL GRADUALLY INCREASE OVER SOUTHWEST AND SOUTH CENTRAL
ARIZONA THURSDAY THROUGH SATURDAY...INTO THE 15 TO 25 PERCENT
RANGE...WITH A SLIGHT CHANCE OF AFTERNOON AND EVENING SHOWERS AND
THUNDERSTORMS IN SOUTHERN GILA COUNTY. AFTERNOON SOUTHWEST WINDS 10
TO 15 MPH. FAIR RECOVERY AT NIGHT.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...PERCHA/KUHLMAN
AVIATION...PERCHA
FIRE WEATHER...VASQUEZ
AREA FORECAST DISCUSSION
NWS TUCSON AZ
901 PM MST SAT AUG 1 2015
.SYNOPSIS...A GRADUAL DAILY REDUCTION IN THUNDERSTORM COVERAGE WILL
THEN OCCUR SUNDAY THROUGH TUESDAY. SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS MAINLY FROM TUCSON EAST AND SOUTH WILL RETURN DURING
THE LATTER PART OF THE UPCOMING WEEK.
&&
.DISCUSSION...SHOWERS AND THUNDERSTORMS CONTINUED TO DIMINISH LATE
THIS EVENING AFTER A RATHER ACTIVE AFTERNOON. LATEST HRRR SOLUTION
SUGGESTED THAT THE REMAINING SHOWERS WILL DISSIPATE BY MIDNIGHT WITH
SKIES CLEARING OVERNIGHT. CURRENT FORECAST LOOKED ON TRACK...SO JUST
SOME MINOR ADJUSTMENTS TO THE GRIDDED POP FIELD THIS EVENING. PLEASE
REFER TO THE ADDITIONAL SECTIONS FOR MORE DETAILS.
&&
.AVIATION...VALID THRU 03/06Z.
EXPECT CLEARING SKIES LATE TONIGHT INTO SUNDAY MORNING BEFORE
REDEVELOPMENT OF ISO-SCT SHRA/TSRA DURING THE EARLY
AFTERNOON...MAINLY E OF KTUS/KOLS AND ESP NEAR TERRAIN. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SOUTHWEST WINDS ALOFT ON SUNDAY WILL USHER DRIER AIR
INTO THE REGION...WHICH WILL LIMIT PRECIPITATION CHANCES ON MONDAY
AND ESPECIALLY ON TUESDAY. HIGH PRESSURE RETURNS TO A MORE FAVORABLE
LOCATION FOR DAILY CHANCES OF MONSOON SHOWERS AND THUNDERSTORMS FROM
WEDNESDAY ONWARD. OUTSIDE OF THUNDERSTORM WIND GUSTS...20-FT WINDS
WILL GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME
AFTERNOON AND EARLY EVENING BREEZINESS IS LIKELY DUE TO DAYTIME
HEATING... ESPECIALLY THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.PREV DISCUSSION...01/12Z NAM/GFS/ECMWF/CMC WERE IN GOOD AGREEMENT
WITH DEPICTING A DRYING TREND TO COMMENCE SUNDAY AND CONTINUE INTO
TUE...AT LEAST. HIGH PRESSURE ALOFT IS PROGGED TO BE CENTERED OVER
FAR WEST TEXAS SUN MORNING...WITH A SHORTWAVE TROUGH OVER THE GREAT
BASIN AND NWRN ARIZONA. 700-300 MB SWLY FLOW SUN WILL BECOME
INCREASINGLY WLY MON AND CONTINUE WITH GENERALLY LIGHT WLY FLOW TUE
AS THE UPPER HIGH BECOMES POSITIONED JUST SOUTH OF THIS FORECAST
AREA OVER NRN SONORA.
THIS WIND REGIME WILL TRANSLATE INTO ISOLATED TO SCATTERED SHOWERS/
TSTMS FROM TUCSON EWD/SWD SUN AND MON. BY TUE...THERE IS ONLY A
SLIGHT CHANCE OF SHOWERS/TSTMS MAINLY NEAR THE MOUNTAINS WITH DRY
CONDITIONS ELSEWHERE. A SIMILAR PRECIP REGIME MAY ACTUALLY OCCUR
WED...AT LEAST BASED ON THE GFS/ECMWF/CMC SOLUTIONS. FOR NOW...
OPTED TO CONTINUE WITH A SLIGHT CHANCE OF SHOWERS/TSTMS ACROSS MUCH
OF SE ARIZONA WED.
THEREAFTER...THE GFS/ECMWF WERE FAIRLY SIMILAR WITH DEPICTING DEEPER
MOISTURE TO RETURN TO THIS FORECAST AREA STARTING THUR AND
CONTINUING INTO NEXT SAT. THESE SOLUTIONS SEEM PLAUSIBLE AS THE MID-
LEVEL STEERING FLOW BECOMES INCREASINGLY SLY IN RESPONSE TO THE
UPPER HIGH BECOMING POSITIONED AGAIN OVER WEST TEXAS...AND AN UPPER
TROUGH ADJACENT THE CALIFORNIA COAST. THUS...SCATTERED SHOWERS/TSTMS
WILL RETURN THUR-SAT MAINLY FROM TUCSON EWD/SWD TO THE NEW MEXICO/
INTERNATIONAL BORDERS.
EXPECT ABOUT A DEGREE-OR-TWO OF DAILY WARMING SUN-TUE FOLLOWED BY A
VERY GRADUAL REDUCTION IN DAYTIME TEMPS DURING THE LATTER PART OF
THE UPCOMING WEEK.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1124 PM MDT SAT AUG 1 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 238 PM MDT SAT AUG 1 2015
...TYPICAL AUGUST WEATHER CONTINUES ON SUNDAY...
FAIRLY TYPICAL SUMMER PATTERN REMAINS IN PLACE OVER SE CO. WITH
MONSOONAL PLUME CIRCULATING CLOCKWISE AROUND THE UPPER HIGH CENTERED
OVER NM...BEST T-STORM COVERAGE CONTINUES TO BE OVER WRN AND SRN
PORTIONS OF THE CWA. NEWLY OPERATIONAL RADAR IN THE SAN JUANS SHOWS
WIDESPREAD CONVECTION OVER THE SW MTS...JUSTIFYING LIKELY POPS FOR
THE BALANCE OF THE AFTERNOON AND INTO EARLY EVE. MORE QUESTIONABLE
WHETHER STORMS WILL SURVIVE MOVING ONTO THE SERN PLAINS E OF I-
25...BUT ISOLD POPS LOOK APPROPRIATE THERE. TEMPS CONTINUE TO BE
IN THE LOWER 90S FOR THE PLAINS...70S FOR THE HIGH VALLEY AREAS.
EXPECT MOST OF THE T-STORM ACTIVITY TO WANE AFTER SUNSET...HOWEVER
LATEST HRRR AND OTHER GUIDANCE SUGGESTS CONTINUED ISOLD ACTIVITY
OVER THE SW MTS AND SURROUNDING AREAS...SO WILL MAINTAIN AT LEAST
LOW POPS THROUGH THE NIGHT FOR THIS AREA. SOME MODEL SOUNDINGS STILL
SUPPORT LOW CLOUDS OR POSSIBLY EVEN SOME FOG FOR THE SAN LUIS VALLEY
IF SUFFICIENT PRECIP CAN FALL THIS AFTERNOON OR EVE.
TOMORROW...MORE OF THE SAME...BUT A WEAK SHORTWAVE PASSING THROUGH
NW FLOW ON THE E SIDE OF THE UPPER RIDGE COULD SPARK A FEW MORE
STORMS THAN WE ARE CURRENTLY SEEING...ESPECIALLY OVER THE SERN
MTS. SFC WINDS SHIFT TO A STRONGER UPSLOPE COMPONENT SUN
AFTERNOON... WHICH WILL KEEP THE BEST FORCING FOR STORMS ANCHORED
ALONG THE MTS AND ADJACENT LOWLANDS ALONG THE I-25 CORRIDOR.
TEMPS AGAIN SHOULD BE IN THE LOWER TO MID 90S OVER THE PLAINS. ROSE
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 238 PM MDT SAT AUG 1 2015
SUN NIGHT AN UPR TROF IS FORECAST TO EXTEND FROM THE GREAT BASIN
REGION AND ACRS CO. BOTH THE NAM AND GFS SHOW A SHORTWAVE TROF
MOVING INTO THE SERN CORNER OF CO OVERNIGHT AND INTO MON
MORNING...BUT THEY DISAGREE ON ITS IMPACT. BOT MODELS SHOW PCPN
CONTINUING THRU THE NIGHT OVR THE CONTDVD WITH THE POTENTIAL FOR
SOME ISOLD PCPN OVR THE ERN MTNS. FOR FAR ERN PORTIONS OF THE
FORECAST AREA...THE NAM HAS MAINLY SOME ISOLD PCPN OVR THE SERN
CORNER THRU THE NIGHT AND MON MORNING...BUT THE GFS HAS MORE
WIDESPREAD CHANCES OVR THE SERN PLAINS. SINCE THERE IS A DISTURBANCE
IN THE AREA...WL KEEP SOME ISOLD POPS ACRS THE SERN PLAINS THRU THE
NIGHT. THRU THE DAY MON...THAT UPR TROF CONTINUES WORKING ITS WAY
NORTHEASTWARD INTO ID...WY AND NERN CO. THE GFS AND NAM HAVE SCT
PCPN OVR THE HYR TRRN ON MON...WHILE THE NAM IS MAINLY DRY OVR THE
SERN PLAINS IN THE AFTERNOON AND EVENING...BUT THE GFS HINTS AT
ISOLD TO SCT PCPN. MON NIGHT THE NAM SHOWS PCPN ACRS THE FORECAST
AREA ENDING BY LATE EVENING...BUT THE GFS CONTINUES PCPN OVR THE FAR
ERN BORDER AREA INTO THE LATE NIGHT HOURS.
TUE AN UPR RIDGE BUILDS OVR THE AREA AND REMAINS IN PLACE ON
WED...WHICH WL KEEP THE MONSOON MSTR TO THE SOUTH OF THE FORECAST
AREA. SO...DRIER CONDITIONS CAN BE EXPECTED ALTHOUGH THERE MAY STILL
BE ENOUGH MSTR OVR THE AREA FOR A FEW AFTERNOON AND EVENING MTN AREA
SHOWERS/TSTMS. ON THU A DISTURBANCE IS FORECAST TO MOVE ACRS
WY...THEN PUSHING A FRONT THRU ERN CO. THE ECMWF DEVELOPS AND MCS
OVR ERN FOR THU NIGHT...WHILE THE GFS DOES NOT AND LEAVES THE AREA
RATHER DRY. FOR NOW WL GO WITH THE DRY SOLUTION AND SEE HOW THE
SITUATION DEVELOPS.
FRI THE UPR RIDGE WL BE CENTERED TO THE SOUTH OF CO. THE ECMWF
SHOWS THE POTENTIAL FOR A LITTLE MORE MSTR TO WORK ITS WAY BACK
TOWARD CO...BUT THE GFS IS STILL FAIRLY DRY THROUGH SAT.
&&
.AVIATION...
ISSUED AT 1124 PM MDT SAT AUG 1 2015
VFR CONDITIONS ARE ANTICIPATED OVER THE KALS...KCOS AND KPUB TAF
SITES INTO SUNDAY MORNING.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
328 AM EDT SUN AUG 2 2015
.DISCUSSION...
...LOCALLY HEAVY RAINFALL AND GUSTY WINDS WITH STORMS AGAIN TODAY...
CURRENT...KMLB NEXRAD 88D SHOWS SPOTTY LIGHT RAIN ECHOES MOVING FROM
SOUTHWEST TO NORTHEAST ACROSS EAST CENTRAL FL EARLY THIS MORNING.
WATER VAPOR IMAGERY AGAIN SHOWS A BLANKET OF MID/UPPER LEVEL
MOISTURE ACROSS THE REGION ALL SOUTH OF A WEAK QUASI-STATIONARY
FRONTAL BOUNDARY SITUATED OVER THE DEEP SOUTH AND SOUTHEAST U.S.
MSAS/SURFACE OBS SHOW THAT THE SURFACE RIDGE AXIS HAS CREPT NORTH TO
NEAR SOUTH-CENTRAL FL. MID TO UPPER LEVEL TROUGHINESS AGAIN LIES
ACROSS THE AREA. CAPE 915 MHZ PROFILER WINDS OUT OF THE S/SSW
AVERAGE BETWEEN 20 AND 30 KTS OFF THE DECK UP TO AROUND 10.0 KFT.
SURFACE S/SSW WINDS ARE BETWEEN 5 AND 10 MPH WITH TEMPERATURES AND
DEWPOINTS IN THE 70S.
TODAY-TONIGHT...PRECIPITABLE WATER VALUES WILL CONTINUE AROUND 2
INCHES AREAWIDE EARLY...BUT THE GFS SUGGESTS SOME DRIER AIR
FILTERING INTO THE AREA SOUTH OF I-4 LATER IN THE DAY. THE
AFOREMENTIONED SURFACE BOUNDARY TO THE NORTH WILL REMAIN NORTH OF
THE AREA WITH THE SURFACE RIDGE AXIS NEAR LAKE OKEECHOBEE. S/SSW
WINDS WILL INCREASE THIS MORNING AND EARLY AFTERNOON TOWARD AROUND
15 MPH...POSSIBLY FLIRTING WITH 15-20 MPH (BREEZY) AT TIMES AND SOME
HIGHER GUSTS LIKELY. THE IMMEDIATE TREASURE COAST MAY SEE WINDS BACK
TO SSE/SE IN THE AFTERNOON. CONTINUED DEEP MOISTURE WILL MAKE CLOUD
COVER HARD TO OVERCOME FOR MUCH OF THE AREA AGAIN TODAY. AFTERNOON
HIGHS WILL CONTINUE IN THE U80S TO AROUND 90 DEGREES.
THE DEEP/STOUT SOUTHWESTERLY FLOW WILL ALLOW SCT SHRA/ISOLD TSRA
LATER THIS MORNING AND EARLY AFTERNOON TO TRAVERSE THE PENINSULA
WITH SHOWER COVERAGE FORECAST TO BECOME NUMEROUS THIS AFTERNOON WITH
SCATTERED LIGHTNING STORMS. 500 MB TEMPERATURES WILL BE A BIT WARMER
WITH MODELS SHOWING A RANGE BETWEEN -5.5 AND -6.5 DEGREES CELSIUS
ACROSS ECFL. THE 00Z GFS CONTINUES TO HIGHLIGHT FAIRLY GOOD UPPER
LEVEL DIFFLUENCE ACROSS THE EAST COAST/COASTAL WATERS LATER THIS
AFTERNOON/EARLY EVENING. STORM MOVEMENT WILL BE FAIRLY QUICK AND OUT
OF THE SW AT 15 TO 20 KTS. THE MAIN THREATS WITH STRONGER ACTIVITY
CONTINUES TO BE HEAVY DOWNPOURS...GUSTY WINDS TO AROUND 50 MPH AND
FREQUENT LIGHTNING IN A FEW CELLS.
MARINERS ON INLAND LAKES AS WELL AS ACROSS THE INTRACOASTAL/NEAR
SHORE ATLANTIC WATERS WILL NEED TO KEEP AN EYE TO THE SKY WESTWARD
FOR DEVELOPING/APPROACHING STORMS. CONVECTION WILL GRADUALLY
DECREASE THROUGH THE EVENING...THOUGH A SCHC FOR A SHOWER WILL
CONTINUE OVERNIGHT ALMOST EVERYWHERE. CONSIDERABLE CLOUDINESS TO
MOSTLY CLOUDY SKIES WILL CONTINUE THIS EVENING AND OVERNIGHT.
OVERNIGHT LOWS IN THE 70S. S/SSW WINDS WILL GRADUALLY DECREASE TO
AROUND 5 MPH THIS EVENING AND OVERNIGHT.
MONDAY...SFC LOW IS FORECAST TO TRACK ACROSS SE GA AND MOVE NE
THROUGH THE AFTERNOON WITH A TRAILING AREA OF DEEP MOISTURE
STRETCHING SOUTH OF THE LOW ACROSS NRN SECTIONS MONDAY MORNING AND
DROPPING SLOWLY SE INTO LATE AFTERNOON. THIS SHOULD ALLOW FOR MOSTLY
CLOUDY SKIES ACROSS NRN SECTIONS IN THE MORNING WITH SOME EARLY
MORNING SHOWERS. EXPECT CONVECTION TO BECOME LIKELY ACROSS THE NRN
ZONES INTO MID DAY INTO THE AFTERNOON WITH SCATTERED SHOWERS AND
STORMS ACROSS SRN SECTIONS BY MID TO LATE AFTERNOON. LOCALLY HEAVY
RAINFALL IS LIKELY WITH STORMS AND GUSTY WINDS AS STORMS APPROACH
THE EAST COAST MAINLY NORTH OF FT PIERCE. HIGHS WILL BE IN THE MID
TO UPPER 80S NORTH TO LOWER 90S ACROSS SRN ZONES WHERE MORE MORNING
SUN IS EXPECTED BEFORE SCATTERED STORMS DEVELOP INTO THE AFTERNOON.
TUESDAY...THE SFC AND LOW LVL RIDGE WILL WORK SLOWLY NORTHWARD TWD
FAR SRN SECTIONS OF THE FORECAST AREA AS WE BEGIN TO LOSE THE
INFLUENCE OF THE SFC LOW AND FRONTAL BOUNDARY THAT HAD BEEN NORTH OF
THE AREA FOR THE LAST WEEK OR SO. OVERALL WILL SEE LIGHTER WINDS IN
THE SFC TO 850 LAYER WITH LATE DAY BOUNDARY INTERACTIONS FAVORING
INTERIOR SECTIONS ESPEC INLAND FROM THE TREASURE COAST. WILL
FORECAST 30-40 POPS NEAR THE EAST COAST AND 40-50 PCT OVER THE
INTERIOR. HIGHS FROM 89 TO 92 DEGS.
WED...SOUTHERLY LOW LVL FLOW IS FORECAST AROUND THE ATLC RIDGE WITH
INLAND MOVING SEA BREEZE BOUNDARIES MOVING TWD THE NRN INTERIOR LATE
IN THE AFTERNOON INTO THE EARLY EVENING. LOWEST POPS AROUND 30 PCT
WILL BE ALONG THE TREASURE COAST WHERE THE SEA BREEZE SHOULD MOVE
INLAND INTO MID AFTERNOON. WILL FORECAST 40-50 PCT ACROSS THE
INTERIOR FOR MID TO LATE AFTERNOON SCATTERED STORMS. HIGHS NEAR 90
COASTAL TO THE LOWER 90S FOR THE INTERIOR.
THU...THE LOW LVL RIDGE WILL SHIFT A BIT SOUTHWARD AGAIN BY THU AFTN
AS A 500 MB S/W TROUGH MOVES INTO THE SE STATES. MOISTURE LEVELS
APPEAR SUFFICIENT FOR SCATTERED STORMS WHICH WILL MOVE TWD THE EAST
COAST LATE IN THE DAY WITH STEERING FLOW FROM THE WEST INTO THE
EVENING. RAIN CHANCES 40 PCT CSTL TO 50 PCT FROM ORLANDO SOUTH
ACROSS THE INTERIOR. HIGHS 90-92 DEGS.
FRI-SUN...A DEEPENING L/W TROUGH ACROSS THE ERN STATES FOR THE
UPCOMING WEEKEND WILL PRODUCE DEEP LAYER WESTERLY FLOW AND
INCREASING MOISTURE LEVELS WHICH WILL ALLOW FOR EASTWARD MOVING
SCATTERED SHOWERS AND STORMS EACH DAY...LIKELY ALONG A PROGRESSIVE
WEST COAST SEA BREEZE AND POSSIBLY ALONG AN EAST COAST BREEZE PINNED
NEAR THE EAST COAST IF THE WESTERLY FLOW IS NOT TOO STRONG. WILL
KEEP RAIN CHANCES MAINLY IN THE 40-50 PCT RANGE FOR THE UPCOMING
WEEKEND. HIGHS WILL REMAIN MAINLY IN THE LOWER 90S.
&&
.AVIATION...A SIMILAR PATTERNS SITS IN PLACE FROM THE PREVIOUS
COUPLE OF DAYS. THE HRRR HINTS AGAIN AT CONVECTION ACROSS THE
WESTERN PENINSULA MOVING INTO ECFL LATE MORNING/EARLY AFTERNOON
MOVING OFF OF THE COAST EARLY TO MID AFTERNOON (NORTH TO SOUTH).
MOIST CONDITIONS CONTINUE IN A DEEP SWRLY FLOW PATTERN WITH
SHRA/TSRA BECOMING SCT-NMRS AGAIN AT TIMES THROUGH THE AFTN/EARLY
EVENING. SKIES TO REMAIN CONSIDERABLY TO MOSTLY CLOUDY THROUGH THE
PERIOD. S/SSW SFC WINDS A BIT STRONGER AS WITH YESTERDAY AND GUSTY
AT TIMES. ALONG THE TREASURE COAST WINDS MAY BACK TO S/SSE AS THE
SFC RIDGE AXIS LIES NEAR LAKE OKEECHOBEE. AS WITH PREVIOUS
DAYS...PRECIPITATION LATE THIS MORNING/EARLY THIS AFTERNOON MAY
DISTORT THE WIND FIELD WITH OCCASIONAL LIGHTER SURFACE WINDS THAN
FORECAST WITH VARYING DIRECTION. TEMPO IFR/MVFR IN SHRA/TSRA. CELL
MOVEMENT TOWARD THE NE AT 15 TO 20 KTS. FOR TAFS...VCSH/VCTS FROM
LATE MORNING/EARLY AFTERNOON WITH TEMPO GROUPS ADDED AS CONFIDENCE
PERMITS. THREATS FROM CONVECTION CONTINUES TO BE LIGHTNING...
TORRENTIAL DOWNPOURS AND GUSTY WINDS. ACTIVITY WILL WIND DOWN
THROUGH THE EVENING AND WINDS WILL DECREASE.
&&
.MARINE...TODAY-TONIGHT...THE SURFACE RIDGE AXIS IS OVER THE SOUTH-
CENTRAL FL PENINSULA WHERE IT WILL LIKELY REMAIN OVER THE NEXT 24
HRS. CAUTIONARY STATEMENTS SEEM APPROPRIATE AGAIN FOR GUSTY S/SSW
WINDS OFFSHORE/NORTH OF SEBASTIAN INLET. WILL ALLOW FUTURE SHIFTS TO
MONITOR AND ADJUST AS NECESSARY. SLIGHTLY LOWER WIND SPEEDS ARE
FORECAST THIS EVENING/OVERNIGHT HERE. WIND SPEEDS MAINLY 10-15 KTS
ELSEWHERE. SEAS 2-3 FT NEAR SHORE AND 3-4 FT OFFSHORE.
WINDS/SEAS WILL BE LOCALLY HIGHER INVOF QUICK MOVING OFFSHORE
SHOWERS/STORMS. OFFSHORE MOVING LIGHTNING STORMS REMAIN A THREAT
THROUGH THE DAY/EVENING AND COVERAGE WILL BE FAIRLY HIGH LATER
TODAY. MARINERS SHOULD REMEMBER THAT STRONG WINDS MAY ARRIVE WELL
AHEAD OF RAIN AND LIGHTNING.
MONDAY...SW WINDS MAINLY 10-15 KNOTS WITH OFFSHORE MOVING SHOWERS
AND STORMS DURING THE AFTERNOON AND EARLY EVENING HOURS. A FEW COULD
BE STRONG WITH GUSTY WINDS GREATER THAN 35 KNOTS. SEAS MAINLY 2-3 FT
TO 4 FT ACROSS THE NRN OFFSHORE WATERS.
TUE-THU...S-SW WINDS TUE WILL BECOME SOUTHERLY AROUND THE ATLC RIDGE
BY WED/THU AND DECREASE TO AROUND 10 KNOTS. SEAS 2 FT NEAR SHORE TO
3 FT OFFSHORE. A LOWER COVERAGE OF ATLC SHOWERS/STORMS IS EXPECTED
INTO MID WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 89 73 87 73 / 60 30 60 20
MCO 89 74 88 73 / 60 20 60 20
MLB 91 76 89 75 / 50 20 60 30
VRB 91 72 91 72 / 50 30 50 30
LEE 86 75 87 74 / 60 30 60 20
SFB 89 75 88 73 / 60 20 60 20
ORL 89 75 88 75 / 60 20 60 20
FPR 91 73 91 73 / 50 30 50 30
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM/AVIATION...SEDLOCK
LONG TERM....VOLKMER
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
142 AM EDT SUN AUG 2 2015
.SYNOPSIS...
A WEAK PRESSURE TROUGH WILL REMAIN IN THE FORECAST AREA THROUGH
MONDAY. DEEPER MOISTURE WILL REMAIN SUPPRESSED EAST AND SOUTH OF
THE AREA.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
THE UPPER-LEVEL PATTERN FEATURES A RIDGE OUT WEST WITH A BROAD TROUGH
FROM THE GREAT LAKES TO THE EAST COAST. WATER VAPOR SATELLITE
IMAGERY SHOWED DRY AIR ALOFT ACROSS THE MIDLANDS AND CSRA.
WEAK FRONTAL BOUNDARY NEAR THE SOUTHERN TIP OF THE FORECAST AREA
THIS EVENING. SHARP MOISTURE GRADIENT ACROSS THE REGION LATE THIS
EVENING AS SEABREEZE HAD PUSHED INTO THE CENTRAL MIDLANDS AND CSRA
BRINGING WITH IT DEWPOINT TEMPERATURES IN THE UPPER 60S/LOWER 70S.
AHEAD OF THIS BOUNDARY DEWPOINT TEMPERATURES REMAIN IN THE MID
50S/MID 60S. MODELS SHOWING POOL OF MOISTURE NEAR THE SURFACE WITH
DRY AIR ALOFT. WV LOOP CONTINUES TO SHOW DRY AIR ALOFT ACROSS THE
AREA. EXPECT SOME FOG TO FORM TOWARD MORNING GIVEN MOSTLY CLEAR
SKIES AND LOW LEVEL MOISTURE. BEST CHANCE FOR FOG WILL BE ACROSS
THE EASTERN MIDLANDS/CSRA WHERE HIGHEST DEWPOINTS CURRENTLY
RESIDE.
MET MOS GUIDANCE HAS COOL BIAS OVERNIGHT MINS HAVE STAYED WITH
SLIGHTLY WARMER OVERNIGHT TEMPERATURES WITH LOWS IN THE UPPER 60S
TO LOWER 70S TONIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
THE WEAK FRONTAL BOUNDARY WILL REMAIN ACROSS EASTERN SOUTH
CAROLINA THROUGH THE PERIOD. MODELS APPEARS TO BE DRIER ACROSS
CENTRAL SOUTH CAROLINA AND CSRA AND SOUNDINGS LIKELY CAPPED. WIDELY
SCATTERED CONVECTION CONFINED MAINLY IN THE EAST MIDLANDS...LOWER
CSRA. MAX TEMPERATURES MAINLY IN THE MID 90S...LOWS UPPER 60S TO
MID 70S.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
MODELS HAVE BEEN CONSISTENT SHOWING A RIDGE OVER THE CENTRAL US
WITH A BROAD TROUGH ALONG THE EAST COAST. THE FRONTAL BOUNDARY
WILL REMAIN ALONG THE COAST THROUGH EARLY NEXT WEEK BEFORE
DISSIPATING. THE GFS KEEPS THE AREA DRY THROUGH WEDNESDAY. MOISTURE
RETURNS TO THE REGION LATER IN THE WEEK. RAISED POPS INTO THE
30-40 PERCENT THURSDAY THROUGH SATURDAY. HIGH TEMPERATURES IN THE
MID 90S THROUGH MID-WEEK...LOWERING INTO THE LOWER 90S THURSDAY
THROUGH SATURDAY. OVERNIGHT LOWS GENERALLY IN THE LOWER TO MID
70S.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
MOSTLY CLEAR SKIES AND LIGHT WINDS EXPECTED OVERNIGHT...WHICH LEADS
TO FOG CONCERNS. SATELLITE WATER VAPOR IMAGERY INDICATES DRY AIR
ALOFT WHICH TENDS TO AID IN RADIATIONAL COOLING AND FOG DEVELOPMENT.
DESPITE SHALLOW SEA BREEZE OR OUTFLOW BOUNDARY THAT MOVED THROUGH
EARLIER THIS EVENING...DRIER LOW LEVEL AIR EXISTS ACROSS THE NORTHER
NAND CENTRAL FA NEAR CAE/CUB AND IS EXPECTED TO LIMIT FOG POTENTIAL
THERE. HOWEVER...TO THE SOUTH WHERE BETTER LOW LEVEL MLOISTURE
EXISTS...THE FOG POTENTIAL IS GREATER...ESPECIALLY AT THE FOG PRONE
SITES AGS AND OGB. LATEST HRRR INDICATES SOME STRATUS POTENTIAL NEAR
AGS AND DNL AS WELL NEAR WHERE BETTER PRECIP COVERAGE OCCURRED
SATURDAY. WILL INDICATE PREDOMINATE IFR FOG POTENTIAL FOR THE FOG
PRONE SITES AGS AND OGB...AND MVFR FOG AT DNL...AND WILL INDICATE
TEMPO IFR CIGS POSSIBLE AT DNL AND AGS. WILL MAINTAIN VFR
CONDITIONS AT CAE/CUB.
SURFACE BOUNDARY WILL REMAIN NEARLY STATIONARY OVER THE SOUTHERN FA
TODAY. A DRY AND CAPPED ATMOSPHERE WILL REMAIN IN PLACE OVER MOST OF
THE NORTHERN AND CENTRAL FA...AND IS EXPECTED TO PRECLUDE CONVECTION
THERE. AN ISOLATED MAINLY DIURNAL SHOWER OR THUNDERSTORM MAY OCCUR
MAINLY SOUTH POSSIBLY NEAR DNL/AGS/OGB...BUT CHANCES TOO LOW TO
INCLUDE MENTION IN THE TAFS AT THIS TIME.
EXTENDED AVIATION OUTLOOK...
RESTRICTIONS POSSIBLE IN LATE NIGHT/EARLY MORNING FOG.
OTHERWISE...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
...UPDATE TO AVIATION FORECAST DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
19Z WATER VAPOR IMAGERY SHOWS NORTHWEST FLOW ACROSS THE NORTHERN AND
CENTRAL PLAINS WHILE THE CENTER OF A MID LEVEL RIDGE SITS OVER WEST
TX. THE RIDGE AXIS EXTENDED NORTHWEST INTO OR. THE RAP ANALYSIS
SUGGESTS THERE ARE ONLY A COUPLE WEAK VORT MAXIMUM UPSTREAM. ONE
OVER EASTERN NEB AND ANOTHER MOVING INTO SD. AT THE SURFACE, A MESO
HIGH REMAIN OVER CENTRAL NEB WHILE OUTFLOW BOUNDARIES FROM MORNING
CONVECTION HAVE BECOME MORE DIFFUSE ACROSS CENTRAL AND EASTERN KS.
FOR THIS AFTERNOON AND THIS EVENING, THERE REMAINS AN OUTSIDE CHANCE
FOR A STORM TO DEVELOP AS OBJECTIVE ANALYSIS SHOWS MORE THAN ENOUGH
INSTABILITY. HOWEVER SURFACE FLOW HAS BEEN RATHER WEAK SO
CONVERGENCE AND LIFT ALONG ANY OF THE BOUNDARIES HAS ALSO BEEN
RATHER WEAK. SATELLITE SHOWS LITTLE DEVELOPMENT TO THE CU FIELD
ACROSS THE AREA INDICATING THERE HASN`T BEEN MUCH FORCING AS WELL.
AND ANY WEAK VORTICITY ADVECTION FROM THE LEFT OVER CONVECTION IN
EASTERN NEB IS LIKELY PROPAGATING INTO MO. BECAUSE OF THIS THINK THE
CHANCES FOR ANY SPOT TO RECEIVE RAIN IS ONLY ABOUT 10 PERCENT AND
NOT HIGH ENOUGH TO MENTION IN THE FORECAST. ONCE THE BOUNDARY LAYER
STARTS TO COOL, THE THREAT FOR THUNDERSTORMS SHOULD DIMINISH.
OVERNIGHT, MODELS SHOW THE LOW LEVEL JET SETTING UP ACROSS NEB AND
IA WITH NO REAL ORGANIZED ISENTROPIC LIFT ACROSS THE FORECAST AREA.
BECAUSE OF THIS HAVE A DRY FORECAST GOING THROUGH THE NIGHT. THERE
SHOULD BE MOSTLY CLEAR SKIES, SO THINK WITH SOME RADIATIONAL COOLING
LOWS WILL FALL INTO THE UPPER 60S TO AROUND 70.
FOR SUNDAY, THE SETUP LOOKS VERY SIMILAR TO TODAY WITH DECENT
SURFACE BASED INSTABILITY DEVELOPING AND NOT MUCH INHIBITION TO
CONVECTION. WITH A LACK OF LARGE SCALE FORCING, PRECIP CHANCES LOOK
UNLIKELY UNTIL A TROUGH AXIS APPROACHES NORTH CENTRAL KS LATE IN THE
DAY. MOST MODEL SOLUTIONS SHOW THIS BOUNDARY MOVING INTO THE
FORECAST AREA LATE IN THE AFTERNOON BUT THE GFS IS REALLY THE ONLY
ONE THAT DEVELOPS CONVECTION. THE GFS ALSO IS THE WARMEST SOLUTION
AND MAY BE A LITTLE EAGER TO BREAK WHAT CAP THERE IS. WHILE PRECIP
CHANCES DON`T LOOK GREAT, IT`S DIFFICULT TO RULE OUT A CHANCE SO
HAVE SLIGHT CHANCE POPS IN THE FORECAST FOR THE LATE AFTERNOON. WITH
850 TEMPS SLIGHTLY WARMER THAN TODAY, HAVE HIGHS A DEGREE OR SO
WARMER WITH GENERALLY MID 90S EXPECTED.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 326 PM CDT SAT AUG 1 2015
SUNDAY EVENING WILL CONTINUE TO KEEP LOW PRECIPITATION CHANCES ALONG
THE WEAK FRONTAL BOUNDARY AS WELL AS THE INSTABILITY AXIS ACROSS THE
NORTHERN CWA. WILL LITTLE TO NO UPPER SUPPORT AND WEAK SURFACE
CONVERGENCE EXPECT ANY CONVECTION TO BE ON THE WANE AFTER SUNSET.
LOWS SUNDAY NIGHT WILL COOL INTO THE UPPER 60S TO LOWER 70S.
MONDAY FOR MUCH OF THE DAY LOOKS DRY WITH INCREASING CHANCES FROM
LATE AFTERNOON THROUGH EARLY MORNING HOURS ON TUESDAY ESPECIALLY
NEAR THE NEBRASKA BORDER NEAR THE VICINITY OF THE SURFACE FRONTAL
BOUNDARY IN SOUTHERN NEBRASKA. LOW LEVEL JET WILL INCREASE FROM THE
SOUTH AND SOUTHWEST MONDAY NIGHT BEFORE WEAKENING TUESDAY MORNING.
MODELS CONTINUE TO SHOW MID LEVEL SHORTWAVE MOVING THROUGH THE
PLAINS TUESDAY AND TUESDAY NIGHT.
WEDNESDAY THROUGH SATURDAY WILL BE MARKED BY COOLER TEMPERATURES
WITH PRECIPITATION CHANCES OFF AND ON AS WAVES MOVE THROUGH THE
NEARLY ZONAL FLOW ACROSS THE CENTRAL PLAINS. HIGH PRESSURE NOSES
INTO EASTERN KANSAS ON THURSDAY WITH A FRONTAL BOUNDARY SOUTH OF THE
FORECAST AREA. APPROACHING SHORTWAVE TROUGH AND INCREASING
ISENTROPIC LIFT OVER THE FRONT WILL KEEP A CHANCE FOR ELEVATED
THUNDERSTORMS THURSDAY NIGHT THEN CONTINUE ON FRIDAY WITH PASSAGE OF
THE UPPER TROUGH. COOLER HIGH PRESSURE BUILDS IN SATURDAY. COOLER
HIGH TEMPERATURES ARE EXPECTED FROM WEDNESDAY THROUGH SATURDAY IN
THE 80S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1147 PM CDT SAT AUG 1 2015
VFR CONDITIONS ARE LIKELY THROUGH THE TAF PERIOD. SOUTH TO
SOUTHWEST WINDS AT 10 TO 15 KTS ARE EXPECTED FOR MUCH OF THE DAY
SUNDAY BEFORE TAPERING IN THE EVENING.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...WOLTERS
LONG TERM...53
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
350 AM EDT SUN AUG 2 2015
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 350 AM EDT SUN AUG 2 2015
07Z SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER CENTRAL
KENTUCKY. THIS IS HELPING TO KEEP THE SKY MOSTLY CLEAR ACROSS THE
STATE...BUT A SMATTERING OF MID LEVEL CLOUDS ARE DRIFTING OVER
EAST KENTUCKY AND OUT OF THE AREA ATTM. SIMILAR TO THE PAST FEW
NIGHTS...AN INVERSION HAS SET UP WHILE GOOD RADIATIONAL COOLING IS
UNDERWAY. THIS HAS LED TO ANOTHER NIGHT OF RIDGE TO VALLEY
TEMPERATURE DIFFERENCES WITH SOME UPPER 50S FOUND IN THE DEEPER
SPOTS WHILE HILLTOPS ARE RUNNING IN THE MID 60S. WINDS REMAIN
LIGHT TO CALM ACROSS EAST KENTUCKY WITH NOT MUCH EVIDENCE OF FOG
OUT THERE YET. HOWEVER...AGAIN SIMILAR TO THE PAST FEW NIGHTS...
EXPECT THE FOG TO FORM IN THE RIVER VALLEYS BEFORE DAWN ALONG WITH
LOCALLY DENSE PATCHES.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS A BROAD AREA OF
TROUGHING CONTINUES OVER SOUTH CENTRAL CANADA AND DOWN INTO THE
OHIO VALLEY ACROSS TO NEW ENGLAND. A WIGGLE AT THE CORE OF THE
TROUGH TO THE NORTH WILL SEND A LARGE AMOUNT OF ENERGY INTO THE
GREAT LAKES ON MONDAY ALONG WITH A MID LEVEL GRADIENT THAT
TIGHTENS...RESULTING IN FASTER FLOW THROUGH THE OHIO VALLEY. GIVEN
THE AGREEMENT ALOFT WILL FOLLOW A BLENDED SOLUTION WITH EMPHASIS
ON THE HRRR AND NAM12 EARLY ON AND THE BROADER CONSENSUS LATER.
SENSIBLE WEATHER WILL FEATURE ANOTHER PLEASANT DAY WITH FAIRLY LOW
AND COMFORTABLE HUMIDITY LEVELS AND HIGHS GENERALLY IN THE MID
80S UNDER MOSTLY SUNNY SKIES. THIS WILL LEAD INTO ONE MORE NIGHT
OF GOOD RADIATIONAL COOLING AND RIDGE TO VALLEY TEMPERATURE
DIFFERENCES INTO MONDAY MORNING...ALONG WITH PATCHY VALLEY FOG
TOWARDS DAWN. BY MONDAY...THOUGH...THE SFC PATTERN WILL CHANGE
WITH A COLD FRONT PRESSING SOUTH THROUGH THE OHIO VALLEY AND
TOWARD EAST KENTUCKY. THIS WILL LIKELY KICK OFF SHOWERS AND
THUNDERSTORMS NORTH OF THE STATE THAT SHOULD HELP TO SPAWN
ADDITIONAL STORMS TO THE SOUTH WITH TIME THROUGH THE DAY. ANY
STORMS THAT MANAGE TO DEVELOP OUT AHEAD OF THE FRONT IN EAST
KENTUCKY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE OWING
TO HIGH CAPES AND STRENGTHENING MID LEVEL WINDS. THE BEST CHANCES
WILL BE OVER OUR NORTHERN ZONES CLOSER TO THE FRONT AND SPC HAS
INDICATED A SLIGHT RISK FOR SEVERE STORMS THERE. WILL HIGHLIGHT
THIS CONCERN IN THE FORTHCOMING HWO.
STARTED WITH THE SHORTBLEND MODEL FOR THE T/TD/WIND GRIDS THROUGH
THE DAY FOLLOWED BY THE SUPERBLEND INTO MONDAY. DID MAKE SOME
SIGNIFICANT ADJUSTMENTS TO TEMPERATURES THIS MORNING AND TONIGHT
WITH RESPECT TO RIDGE AND VALLEY DIFFERENCES. AS FOR POPS...KEPT
THEM LOW AND IN LINE WITH THE DRY GUIDANCE INTO MONDAY MORNING.
DID GO A BIT HIGHER THAN THE MET AND MAV NUMBERS FOR MONDAY
AFTERNOON TO ACCOUNT FOR THE POTENTIAL INTRUSION OF STORMS...
ORGANIZED OR OTHERWISE...FROM THE NORTH BY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 AM EDT SUN AUG 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON MONDAY NIGHT WITH THE UPPER
LEVEL PATTERN MAINTAINING A RIDGE OVER THE WEST AND THE LONGWAVE
TROUGH OVER THE EASTERN CONUS. A CLOSED LOW OVER THE HUDSON BAY AREA
WILL GRADUALLY SHIFT OFF TO THE EAST THROUGH THE EXTENDED AS BY
THURSDAY...A SERIES OF STRONGER TROUGHS COME ASHORE OVER THE WEST AS
THE WESTERN RIDGE BEGINS TO WEAKEN A BIT AND SHIFT EAST. THIS
THROUGH THE LAST PORTION OF THE EXTENDED WILL BE THE FORECAST
CHALLENGE AS THE BASE OF THE EASTERN TROUGH SETS UP OVER THE MID MS
VALLEY AND THROUGH KY. THE GFS AND EURO DOES ALIGN A BIT WITH THIS
SOLUTION.
CLOSER TO THE SURFACE...THE FRONT THAT HAS PASSED THROUGH ON MONDAY
WILL LAG ACROSS NORTHERN KENTUCKY AS A STATIONARY BOUNDARY DEVELOPS.
THIS AREA BECOMES A FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT AS
THE BOUNDARY SLIDES FURTHER SOUTH THROUGH THE DAY ON TUESDAY AND
TUESDAY NIGHT. BY WEDNESDAY...NORTHWEST FLOW SETS UP OVER THE AREA
AS A SERIES OF UPPER LEVEL WAVES TOPPLE OVER THE THE TOP OF THE
WESTERN RIDGE AND TRACK SOUTHEAST INTO THE OH VALLEY. THE SUPER
BLEND HAS THIS IN IT/S SOLUTION AS WELL WITH THE PATTERN FAVORABLE
FOR NOCTURNAL THUNDERSTORMS AS WELL...ESPECIALLY IF THIS PATTERN FOR
MCS/S REMAIN...WHICH SEEMS LIKELY BASED UPON THE GFS AND EURO
SOLUTIONS . THUS WILL STAY CLOSE TO THE SUPER BLENDS SOLUTION
WEDNESDAY THROUGH FRIDAY KEEPING HIGH CHANCE TO LIKELY POPS DURING
THIS PERIOD.
TOWARDS THE END OF THE EXTENDED ON FRIDAY AND SATURDAY...THE UPPER
LEVEL PATTERN LOSES A BIT AMPLITUDE AND BECOMES MORE ACTIVE AS
ANOTHER SHORTWAVE TAKES AIM AT THE OH VALLEY. HOWEVER...THE GFS AND
EURO DO DIVERGE TOWARDS THE END OF THE EXTENDED. THUS...LACKING
CONFIDENCE...WILL GO NEAR OR SLIGHTLY BELOW THE SUPER BLEND ON POPS.
THE LINGERING TROUGH OVER THE EAST AND SAGGING SOUTH THROUGH THE
EXTENDED WILL KEEP HIGHS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME
OF YEAR. IN SHORT...THE WEDNESDAY THROUGH FRIDAY PERIOD SEEMS TO BE
QUITE ACTIVE AND WET WITH THE END OF THE FORECAST POSSIBLY
CONTINUING THIS TREND WITH A COOLING TREND AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 220 AM EDT SUN AUG 2 2015
A RIDGE OF HIGH PRESSURE WILL KEEP MOSTLY CLEAR SKIES AND LIGHT
WINDS IN PLACE ACROSS THE AREA FOR THE TAF PERIOD. THE BULK OF
ANY FOG THAT FORMS OVERNIGHT SHOULD BE CONFINED TO VALLEY FLOORS
AND NEAR BODIES OF WATER. AS SUCH...THE MAJORITY OF THE TAF SITES
SHOULD ALL REMAIN FREE OF FOG INTO SUNDAY MORNING. THE EXCEPTION
MAY BE SME AND SYM...BOTH WITH THE SMALLEST DEWPOINT DEPRESSION
CURRENTLY...WHERE A PERIOD OF MVFR FOG HAS BEEN FORECAST LATER
TONIGHT. ADDITIONALLY...SOME IFR FOG WILL BE POSSIBLE LOCALLY IN
THE DEEPER VALLEYS THROUGH EARLY SUNDAY MORNING. OTHERWISE...VFR
CONDITIONS WILL PREVAIL THROUGH THE PERIOD ALONG WITH LIGHT AND
VARIABLE WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
526 AM EDT SUN AUG 2 2015
.UPDATE...
A REFINEMENT OF THOUGHTS AFTER PERUSING FRESH ARRIVING HIGH
RESOLUTION GUIDANCE, PARTICULARLY THE RAP, HRRR AND 00Z 3KM
EXPERIMENTAL NAM WHICH APPEAR TO BE SHEDDING SOME LIGHT ON THIS
AFTERNOON AND EVENING`S SEVERE POTENTIAL. ALTHOUGH OVERALL FORECAST
REASONING HAS NOT CHANGED, NEW INFORMATION IS INCREASING CONFIDENCE
THAT AFTERNOON CONVECTION WILL REMAIN CONFINED TO NORTHERN AREAS
ALONG THE NOSE OF THE DEVELOPING LOW-LEVEL JET WHILE AREAS SOUTH OF
M59 REMAIN CAPPED THUS INHIBITING PREMATURE OVERTURNING.
IN ADDITION TO THE PRIMARY THREAT OF UPSCALE GROWTH OF CONVECTION
INTO AN ORGANIZED MCS, A FEW STORMS COULD ALSO DEVELOP IN ADVANCE OF
THIS LINE WITHIN THE CORRIDOR PRECEDING WARM ADVECTION. THIS
PREFRONTAL CONVECTION WILL HAVE STEEP LAPSE RATES AND AN APPRECIABLE
RESERVOIR OF INSTABILITY WITH WHICH TO WORK. THE OFT CONSERVATIVE
07Z RAP INDICATING 0-1KM MLCAPE APPROACHING 2500 J/KG IN MIDLAND/BAY
COUNTY BY 22Z. IN ADDITION, STRENGTHENING SWLY FLOW WILL SUPPORT
ELEVATED BULK SHEAR DURING THIS TIME THUS POTENTIALLY SUPPORTING A
FEW SUPERCELLS AS UPSTREAM CONVECTION ORGANIZES OVER WISCONSIN, LAKE
MICHIGAN, AND NORTHERN LOWER MICHIGAN. GIVEN WELL MIXED/DEEP
BOUNDARY LAYER INDICATED ON FORECAST SOUNDINGS, IT APPEARS THAT A
POTENTIALLY SIGNIFICANT/70MPH, IF RELATIVELY ISOLATED, WIND THREAT
MAY EXIST MAINLY INVOF THE SAGINAW VALLEY IN ADVANCE OF THE MAIN
LINE AS EARLY AS 21/22Z. FOR THE SAME REASON, TORNADO THREAT WOULD
APPEAR LIMITED DUE TO HIGH LCLS. THOUGH THIS AFTN/EVENING`S
CONVECTIVE TRENDS WILL STILL BE CRITICAL, LATEST GUIDANCE DOES
SUPPORT THE OFFICIAL FORECAST STRONGLY ENOUGH TO CONSIDER
ADVERTISING A THREAT FOR 70 MPH WIND GUSTS CONDITIONAL ON MCS
ORGANIZATION. WILL ALLOW TIME FOR UPDATED SPC DAY 1 AND FOR DAY CREW
TO EVALUATE LATEST TRENDS AND HIGH RES GUIDANCE BEFORE ELEVATING
WORDING IN THE HWO AND OTHER PRODUCTS.
FINALLY, AS NOTED IN THE ORIGINAL MORNING FORECAST PACKAGE, A
LIMITED SEVERE THREAT WILL EXIST WITH ANY CONVECTION THAT TRAVERSES
LAND ACROSS THE NORTH DURING THE AFTERNOON HOURS. IF LATEST RAP RUNS
ARE ANY INDICATION, THE THERMODYNAMIC ENVIRONMENT MAY EVOLVE A BIT
FASTER THAN PREVIOUSLY FORECAST YIELDING INCREASED CONFIDENCE IN
SEVERE WIND POTENTIAL AT LEAST OVER THE THUMB PERHAPS AS EARLY AS
18Z SHOULD UPSTREAM CONVECTION DEVELOP WITHIN FAVORABLE WAA/STEEP
LAPSE RATE ENVIRONMENT.
&&
.PREV DISCUSSION...ISSUED 252 AM EDT SUN AUG 2 2015
SHORT TERM...TODAY AND TONIGHT
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MN AND WI DURING THE
PREDAWN HOURS AS A FAST-MOVING LEAD SHORTWAVE PROVIDES FORCING
WITHIN THE STEEP LAPSE RATE ENVIRONMENT BEING DRAWN EAST BY BROAD
CYCLONIC WNW FLOW. THIS ENVIRONMENT WILL RACE EAST THROUGH THE
AFTERNOON FOCUSING A CORRIDOR OF CONVECTION ACROSS PRIMARILY ACROSS
LAKE HURON AND NORTHERN LOWER MICHIGAN. SOUTHEASTERN PORTIONS OF THE
CWA WILL REMAIN LARGELY CAPPED THROUGH PEAK HEATING AS H85
TEMPERATURES RISE WELL INTO THE UPPER TEENS SUPPORTING HIGHS
APPROACHING 90F. HOWEVER, SLIGHTLY WEAKER CAPPING/BETTER FORCING
ACROSS THE NORTH WARRANT AT LEAST A HIGH CHC POP FROM THE SAGINAW
VALLEY INTO THE THUMB, INCREASING TO LIKELY BY LATE THIS AFTN. THIS
ACTIVITY WILL CARRY AT LEAST A LOW END SEVERE RISK 18-00Z NORTH OF
THE I-69 CORRIDOR AS IT WILL RESIDE ALONG THE EASTERN PERIPHERY MORE
STRONGLY SHEARED SWLY FLOW AND AS SURFACE TDS RISE INTO THE MID AND
UPPER 60S SUPPORTING MODERATE DESTABILIZATION. LATEST HRRR RUNS HAVE
A DEPICTION SIMILAR TO EXPECTATIONS, PARTICULARLY WRT TO EXPECTED
SOUTHWARD EXTENT. MEANWHILE 4KM SPC RUN APPEARS ENTIRELY TOO
GENEROUS WITH CONVECTIVE COVERAGE/EVOLUTION WITHIN STRONGLY CAPPED
AREAS.
SECOND AND POTENTIALLY GREATER SEVERE THREAT MAY EXIST TONIGHT,
LARGELY CONDITIONAL ON EXTENT OF PRECEDING AFTERNOON CONVECTION AND
QUALITY OF RECOVERY. DEVELOPING STRONG SWLY FLOW IN ADVANCE OF
PRIMARY TROUGH AXIS WILL CERTAINLY GIVE THE EXPECTED GENESIS AREA
OVER NORTHERN LOWER OR CENTRAL MI A DECENT SHOT AT RECOVERY BY 00Z.
BETWEEN 00-06Z, STRONG HEIGHT FALLS WILL SPREAD ACROSS THE GREAT
LAKES ELICITING A STRONG LLJ RESPONSE AND IMPRESSIVE MEAN WIND
THROUGH THE LOWER ATMOSPHERE. ASSUMING THE ABSENCE OF STABILIZING
EFFECTS OF EARLIER ACTIVITY, CONVECTIVE INITIATION ALONG THE
INTENSIFYING SURFACE TROUGH WOULD HAVE POTENTIAL TO GROW UPSCALE AND
PROPAGATE INTO AN ENVIRONMENT CHARACTERIZED BY 0-1KM BULK SHEAR
AROUND 40KTS, H7-H5 LAPSE RATES IN EXCESS OF 7.5C/KM, AND 0-1KM
MLCAPE OF 1500 TO 2000 J/KG. THREAT WOULD THEN DIMINISH FROM TOWARD
THE FAR SOUTHEAST AS CONVECTION ENCOUNTERS COMBINATION OF
INCREASINGLY CAPPED MID-LEVELS AND NOCTURNAL STABILIZATION.
LONG TERM...
UPPER LEVEL TROUGH AXIS (EXTENDING FROM LARGE UPPER LEVEL LOW
CENTERED OVER NORTHERN ONTARIO) WILL BE IN PLACE ON MONDAY OVER THE
CENTRAL GREAT LAKES...WITH COLD 500 MB TEMPS AROUND -14 C. THE MAIN
SURFACE COLD FRONT SHOULD CLEAR SOUTHERN MICHIGAN SHORTLY AFTER
12Z...AND SOUTHEAST MICHIGAN WILL BEGIN TO DRY OUT WITH SLOWLY
FALLING DEW PTS. HOWEVER...THERE STILL COULD BE JUST ENOUGH RESIDUAL
LOW LEVEL MOISTURE AROUND TO GENERATE SUFFICIENT INSTABILITY TO POP
ISOLATED-SCATTERED SHOWERS AND MAYBE A THUNDERSTORM...AS THERE IS
ALSO A SECONDARILY COLD FRONT WHICH LOOKS TO BE DROPPING SOUTH FROM
NORTHERN LOWER MICHIGAN...PROVIDING THE BETTER FOCUS. 850 MB TEMPS
STILL IN THE LOWER TEENS ON MONDAY...ALLOWING FOR MAXES AROUND 80
DEGREES...WILL FALL INTO THE UPPER SINGLE NUMBERS TO AROUND 10 C BY
TUESDAY...WHICH SHOULD RESULT IN MAXES HOLDING IN THE MID/UPPER 70S.
A SPOKE OF UPPER LEVEL ENERGY IS FORECASTED TO SWING THROUGH
NORTHERN LOWER MICHIGAN DURING TUESDAY..COUPLED WITH THE DAYTIME
INSTABILITY COULD TOUCH OF A FEW SHOWERS NORTH OF I-69...OTHERWISE
UPPER LEVEL NORTHWEST CONFLUENT FLOW/GENERAL SUBSIDENCE REGIME LOOKS
TO PERSIST AT LEAST INTO WEDNESDAY...SUPPORTING SLOWLY STRENGTHENING
HIGH PRESSURE OVER LOWER MICHIGAN...PROVIDING FAVORABLE RADIATING
NIGHTTIME CONDITIONS ALLOWING MINS TO FALL INTO THE LOW/MID
50S...WITH HIGHS STILL STUCK IN THE 70S FOR WEDNESDAY.
MARINE...
SOUTHWEST WINDS WILL BE INCREASING TODAY AHEAD OF A COLD
FRONT...WITH 25 KNOT GUSTS EXPECTED ACROSS ALL NEARSHORE
WATERS...AND SMALL CRAFT ADVISORIES WILL CONTINUE. COLD FRONT
ARRIVING TONIGHT LOOKS TO TRIGGER THUNDERSTORMS...WHICH COULD BE
SEVERE...PRODUCING WINDS OF 50 KNOTS. WINDS WILL TURN WEST AND THEN
NORTHWEST BEHIND THE FRONT DURING MONDAY. WIND SPEEDS MONDAY LOOK TO
BE GREATEST OVER NORTHERN LAKE HURON...WHERE THEY WILL REACH BETWEEN
15 TO 25 KNOTS MONDAY NIGHT THROUGH TUESDAY NIGHT AS COOLER AIR
SETTLES OVER THE CENTRAL GREAT LAKES REGION. THERE WILL BE A CHANCE
OF SHOWERS AND ISOLATED THUNDERSTORMS OVER LAKE HURON DURING THIS
TIME FRAME AS WELL.
&&
.AVIATION...ISSUED 1147 PM EDT SAT AUG 1 2015
SW WINDS WILL INCREASE LATE SUN MORNING INTO SUN AFTERNOON DUE BOTH
TO DIURNAL MIXING AND A STRENGTHENING WSW GRADIENT IN ADVANCE OF AN
APPROACHING COLD FRONT. AN INFLUX OF INSTABILITY DURING THE DAY WILL
LEAD TO INCREASING CHANCES FOR THUNDERSTORMS...TIMING OF WHICH
CARRIES A GOOD DEAL OF UNCERTAINTY AT THIS EARLY STAGE IN THE
FORECAST.
FOR DTW...THE TWO MOST PROBABLE TIME PERIOD FOR THUNDERSTORM
IMPACTING METRO WILL BE SUN AFTERNOON WITH THE INFLUX OF INSTABILITY
AND LATE SUN EVENING/NIGHT AHEAD OF A COLD FRONT.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM IN THUNDERSTORMS SUNDAY AFTERNOON AND NIGHT.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM NOON EDT TODAY THROUGH THIS EVENING
FOR MIZ049.
LAKE HURON...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LHZ421-422-441>443.
LAKE ST CLAIR...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LEZ444.
&&
$$
UPDATE.......JVC
AVIATION.....SC
SHORT TERM...JVC
LONG TERM....SF
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
252 AM EDT SUN AUG 2 2015
.SHORT TERM...TODAY AND TONIGHT
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MN AND WI DURING THE
PREDAWN HOURS AS A FAST-MOVING LEAD SHORTWAVE PROVIDES FORCING
WITHIN THE STEEP LAPSE RATE ENVIRONMENT BEING DRAWN EAST BY BROAD
CYCLONIC WNW FLOW. THIS ENVIRONMENT WILL RACE EAST THROUGH THE
AFTERNOON FOCUSING A CORRIDOR OF CONVECTION ACROSS PRIMARILY ACROSS
LAKE HURON AND NORTHERN LOWER MICHIGAN. SOUTHEASTERN PORTIONS OF THE
CWA WILL REMAIN LARGELY CAPPED THROUGH PEAK HEATING AS H85
TEMPERATURES RISE WELL INTO THE UPPER TEENS SUPPORTING HIGHS
APPROACHING 90F. HOWEVER, SLIGHTLY WEAKER CAPPING/BETTER FORCING
ACROSS THE NORTH WARRANT AT LEAST A HIGH CHC POP FROM THE SAGINAW
VALLEY INTO THE THUMB, INCREASING TO LIKELY BY LATE THIS AFTN. THIS
ACTIVITY WILL CARRY AT LEAST A LOW END SEVERE RISK 18-00Z NORTH OF
THE I-69 CORRIDOR AS IT WILL RESIDE ALONG THE EASTERN PERIPHERY MORE
STRONGLY SHEARED SWLY FLOW AND AS SURFACE TDS RISE INTO THE MID AND
UPPER 60S SUPPORTING MODERATE DESTABILIZATION. LATEST HRRR RUNS HAVE
A DEPICTION SIMILAR TO EXPECTATIONS, PARTICULARLY WRT TO EXPECTED
SOUTHWARD EXTENT. MEANWHILE 4KM SPC RUN APPEARS ENTIRELY TOO
GENEROUS WITH CONVECTIVE COVERAGE/EVOLUTION WITHIN STRONGLY CAPPED
AREAS.
SECOND AND POTENTIALLY GREATER SEVERE THREAT MAY EXIST TONIGHT,
LARGELY CONDITIONAL ON EXTENT OF PRECEDING AFTERNOON CONVECTION AND
QUALITY OF RECOVERY. DEVELOPING STRONG SWLY FLOW IN ADVANCE OF
PRIMARY TROUGH AXIS WILL CERTAINLY GIVE THE EXPECTED GENESIS AREA
OVER NORTHERN LOWER OR CENTRAL MI A DECENT SHOT AT RECOVERY BY 00Z.
BETWEEN 00-06Z, STRONG HEIGHT FALLS WILL SPREAD ACROSS THE GREAT
LAKES ELICITING A STRONG LLJ RESPONSE AND IMPRESSIVE MEAN WIND
THROUGH THE LOWER ATMOSPHERE. ASSUMING THE ABSENCE OF STABILIZING
EFFECTS OF EARLIER ACTIVITY, CONVECTIVE INITIATION ALONG THE
INTENSIFYING SURFACE TROUGH WOULD HAVE POTENTIAL TO GROW UPSCALE AND
PROPAGATE INTO AN ENVIRONMENT CHARACTERIZED BY 0-1KM BULK SHEAR
AROUND 40KTS, H7-H5 LAPSE RATES IN EXCESS OF 7.5C/KM, AND 0-1KM
MLCAPE OF 1500 TO 2000 J/KG. THREAT WOULD THEN DIMINISH FROM TOWARD
THE FAR SOUTHEAST AS CONVECTION ENCOUNTERS COMBINATION OF
INCREASINGLY CAPPED MID-LEVELS AND NOCTURNAL STABILIZATION.
&&
.LONG TERM...
UPPER LEVEL TROUGH AXIS (EXTENDING FROM LARGE UPPER LEVEL LOW
CENTERED OVER NORTHERN ONTARIO) WILL BE IN PLACE ON MONDAY OVER THE
CENTRAL GREAT LAKES...WITH COLD 500 MB TEMPS AROUND -14 C. THE MAIN
SURFACE COLD FRONT SHOULD CLEAR SOUTHERN MICHIGAN SHORTLY AFTER
12Z...AND SOUTHEAST MICHIGAN WILL BEGIN TO DRY OUT WITH SLOWLY
FALLING DEW PTS. HOWEVER...THERE STILL COULD BE JUST ENOUGH RESIDUAL
LOW LEVEL MOISTURE AROUND TO GENERATE SUFFICIENT INSTABILITY TO POP
ISOLATED-SCATTERED SHOWERS AND MAYBE A THUNDERSTORM...AS THERE IS
ALSO A SECONDARILY COLD FRONT WHICH LOOKS TO BE DROPPING SOUTH FROM
NORTHERN LOWER MICHIGAN...PROVIDING THE BETTER FOCUS. 850 MB TEMPS
STILL IN THE LOWER TEENS ON MONDAY...ALLOWING FOR MAXES AROUND 80
DEGREES...WILL FALL INTO THE UPPER SINGLE NUMBERS TO AROUND 10 C BY
TUESDAY...WHICH SHOULD RESULT IN MAXES HOLDING IN THE MID/UPPER 70S.
A SPOKE OF UPPER LEVEL ENERGY IS FORECASTED TO SWING THROUGH
NORTHERN LOWER MICHIGAN DURING TUESDAY..COUPLED WITH THE DAYTIME
INSTABILITY COULD TOUCH OF A FEW SHOWERS NORTH OF I-69...OTHERWISE
UPPER LEVEL NORTHWEST CONFLUENT FLOW/GENERAL SUBSIDENCE REGIME LOOKS
TO PERSIST AT LEAST INTO WEDNESDAY...SUPPORTING SLOWLY STRENGTHENING
HIGH PRESSURE OVER LOWER MICHIGAN...PROVIDING FAVORABLE RADIATING
NIGHTTIME CONDITIONS ALLOWING MINS TO FALL INTO THE LOW/MID
50S...WITH HIGHS STILL STUCK IN THE 70S FOR WEDNESDAY.
&&
.MARINE...
SOUTHWEST WINDS WILL BE INCREASING TODAY AHEAD OF A COLD
FRONT...WITH 25 KNOT GUSTS EXPECTED ACROSS ALL NEARSHORE
WATERS...AND SMALL CRAFT ADVISORIES WILL CONTINUE. COLD FRONT
ARRIVING TONIGHT LOOKS TO TRIGGER THUNDERSTORMS...WHICH COULD BE
SEVERE...PRODUCING WINDS OF 50 KNOTS. WINDS WILL TURN WEST AND THEN
NORTHWEST BEHIND THE FRONT DURING MONDAY. WIND SPEEDS MONDAY LOOK TO
BE GREATEST OVER NORTHERN LAKE HURON...WHERE THEY WILL REACH BETWEEN
15 TO 25 KNOTS MONDAY NIGHT THROUGH TUESDAY NIGHT AS COOLER AIR
SETTLES OVER THE CENTRAL GREAT LAKES REGION. THERE WILL BE A CHANCE
OF SHOWERS AND ISOLATED THUNDERSTORMS OVER LAKE HURON DURING THIS
TIME FRAME AS WELL.
&&
.AVIATION...ISSUED 1147 PM EDT SAT AUG 1 2015
SW WINDS WILL INCREASE LATE SUN MORNING INTO SUN AFTERNOON DUE BOTH
TO DIURNAL MIXING AND A STRENGTHENING WSW GRADIENT IN ADVANCE OF AN
APPROACHING COLD FRONT. AN INFLUX OF INSTABILITY DURING THE DAY WILL
LEAD TO INCREASING CHANCES FOR THUNDERSTORMS...TIMING OF WHICH
CARRIES A GOOD DEAL OF UNCERTAINTY AT THIS EARLY STAGE IN THE
FORECAST.
FOR DTW...THE TWO MOST PROBABLE TIME PERIOD FOR THUNDERSTORM
IMPACTING METRO WILL BE SUN AFTERNOON WITH THE INFLUX OF INSTABILITY
AND LATE SUN EVENING/NIGHT AHEAD OF A COLD FRONT.
//DTW THRESHOLD PROBABILITIES...
* MEDIUM IN THUNDERSTORMS SUNDAY AFTERNOON AND NIGHT.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LHZ421-422-441>443.
LAKE ST CLAIR...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LEZ444.
&&
$$
SHORT TERM...JVC
LONG TERM....SF
MARINE.......SF
AVIATION.....SC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
121 AM EDT SUN AUG 2 2015
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 323 PM EDT SAT AUG 1 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALOFT OVER
THE GREAT LKS BTWN CLOSED UPR LO OVER HUDSON BAY AND RDG ACROSS THE
WRN CONUS. THE 12Z INL/GRB RAOBS SHOW A RELATIVELY DRY...CAPPED
ENVIRONMENT...SO THE DIURNAL CU THAT POPPED UP HAVE BEEN FAIRLY
SHALLOW WITH LARGE SCALE DEEP LYR QVECTOR DVGC/SUBSIDENCE
DOMINATING. THE ONLY EXCEPTION IS OVER THE SE CWA E OF ESCANABA...
WHERE RADAR INDICATES A FEW SHOWERS HAVE POPPED UP IN AN AREA CLOSER
TO SOME DEEPER MSTR/LESS CAPPED ENVIRONMENT SHOWN ON THE 12Z APX
RAOB AND WHERE LLVL CNVGC HAS BEEN ENHANCED BY LK BREEZE CNVGC.
LOOKING UPSTREAM...A SHRTWV IS DROPPING SEWD THRU MANITOBA. THERE IS
A BAND OF CLDS AND A FEW SHOWERS ASSOCIATED WITH AXIS OF HIER H7 RH
IN AREA OF DPVA/H7-5 QVECTOR CNVGC MOVING INTO NW ONTARIO AHEAD OF
THIS FEATURE. FARTHER AWAY...ANOTHER SHRTWV TOPPING WRN RDG IS
MOVING ESEWD THRU SASKATCHEWAN.
MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON SHOWER/TS CHANCES
ASSOCIATED MAINLY WITH THE TWO SHRTWVS NOTED ABOVE.
TNGT...FIRST SHRTWV OVER MANITOBA IS FCST TO SLIDE SEWD THRU NW
ONTARIO...WITH SHARPER DPVA/DEEP LYR QVECTOR CNVGC REMAINING TO THE
N. ALTHOUGH THE LLVL FLOW IS FCST TO BACK TOWARD THE WSW TO THE S OF
THE TRACK OF THIS DISTURBANCE...GUIDANCE INDICATES THE MOST
IMPRESSIVE MSTR CNVGC WL REMAIN TO THE S IN WI...JUST BRUSHING THE
BORDER. WITH THE DISCONNECT BTWN THIS MOISTENING TO THE S AND THE
MORE IMPRESSIVE DYNAMIC SUPPORT REMAINING TO THE N...SUSPECT PCPN
OVER MUCH OF UPR MI WL BE RATHER LIMITED BTWN AXES OF HIER POPS TO
THE N AND ALONG THE SRN CWA/WI. INCRSG PWAT AND WSW FLOW WL TEND TO
LIMIT THE DIURNAL TEMP DROP.
SUN...DPVA/DEEP LYR QVECTOR CNVGC IN ADVANCE OF SHRTWV NOW MOVING
THRU SASKATCHEWAN IS FCST TO ARRIVE OVER SLOW MOVING...WEAKENING
COLD FNT THAT WL BE DROPPING SLOWLY SE ACRS THE CWA ATTENDANT TO
FIRST DISTURBANCE EXITING INTO QUEBEC. SOME OF THE MODELS...
ESPECIALLY THE 12Z GFS...ALSO HINT AT THE POTENTIAL FOR SOME
ENHANCED UPR DVGC IN RRQ OF EXITING H3 JET MAX SUPPORTING THE FIRST
DISTURBANCE AND EXIT REGION OF INCOMING JET STREAK ASSOCIATED WITH
2ND SHRTWV. SINCE THIS FORCING WL BE ARRIVING DURING PERIOD OF
DAYTIME HEATING...SUSPECT SHOWERS/TS WL BECOME MORE NUMEROUS. SO
TENDED TO BUMP POPS UP INTO THE LIKELY RANGE OVER MUCH OF THE CWA.
WITH INCRSG H85-5 RH...THERE ARE CONCERNS ABOUT HOW MORE CLDS WL
IMPACT SFC DESTABILIZATION. THE 12Z NAM SHOWS MUCAPE AS HI AS 2500-
3000 J/KG OVER THE SCENTRAL UNDER AREA OF STEEP H7-5 LAPSE RATES
APRCHG 8C/KM PER THE THE 12Z GFS. ALTHOUGH MOST OF THE GUIDANCE
SUGGESTS THE BULK OF THE PCPN WL FALL ON THE COOL SIDE OF THE FNT
AND THERE WL BE A GOOD DEAL OF CLD COVER THAT SUG THE NAM FCST
MUCAPE IS TOO HI...TS THAT FORM ALONG AND AHEAD OF THE FNT
ESPECIALLY OVER THE SCENTRAL COULD TURN STRONG TO SEVERE WITH DEEP
LYR SHEAR NEAR 40 KTS. IN FACT...THE NEW SPC OUTLOOK FOR SUN AS
SHIFTED THE NRN EDGE OF MARGINAL RISK FOR SVR STORMS AS FAR N AS SRN
MNM COUNTY. POPS WL DIMINISH FM THE NW BY MID/LATE AFTN FOLLOWING
ARRIVAL OF SUBSIDENCE/MID LVL DRYING FOLLOWING THE SHRTWV.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 317 PM EDT SAT AUG 1 2015
IMPACTS...COOLER TEMPERATURES AND GREATER MOISTURE WILL HAVE A
POSITIVE IMPACT ON FIRE WEATHER...AT LEAST SOMEWHAT LOWERING
CONCERNS.
A TROUGH/COLD FRONT AND ASSOCIATED PRECIPITATION WILL BE MOSTLY OUT
OF THE AREA BY 00Z MON AS THE UPPER LOW THAT HAS BEEN SITTING OVER
HUDSON BAY MOVES S INTO ONTARIO. AS THE LOW MOVES FROM EXTREME NRN
ONTARIO AT 00Z MON TO THE ONTARIO/QUEBEC BORDER E OF LAKE SUPERIOR
BY 00Z WED...THE CORE OF COLDEST AIR (850MB TEMPS OF 3-4C) WILL
SLIDE INTO THE CWA. THE COLDER MID LEVELS WILL ALLOW FOR CONVECTIVE
SHOWERS MON THROUGH TUE AS LOW LEVEL MOISTURE WILL BE INCREASED AND
SUBTLE SHORTWAVES WILL BE MOVING THROUGH. SFC TEMPS WILL BE 7-10
DEGREES BELOW NORMAL WITH HIGHS IN THE MID 60S TO MID 70S. LOWS WILL
BE FROM THE MID 40S INLAND TO THE MID 50S NEAR THE GREAT LAKES.
TUE NIGHT THROUGH WED NIGHT WILL SEE A SFC RIDGE MOVE
OVERHEAD...WITH NO PRECIP EXPECTED. TEMPS MAY BE A DEGREE OR TWO
WARMER THAN TUE WITH HIGHS IN THE UPPER 60S TO LOW 70S. THERE WILL
STILL BE ENOUGH MOISTURE TUE NIGHT TO KEEP TEMPS FROM FALLING INTO
THE 30S AND WED NIGHT MAY SEE INCREASING CLOUD COVER AND RETURN FLOW
TO KEEP TEMPS FROM FALLING TO CONCERNING LEVELS.
THE REST OF THE PERIOD THU THROUGH SAT IS QUITE A BIT MORE UNCERTAIN
IN EXACT DETAILS AS CONDITIONS LOOK TO BE DRIVEN LARGELY BY
SHORTWAVES. SLIGHT CHANCES OF PRECIP EACH DAY AS GIVEN BY CONSENSUS
GUIDANCE IS REASONABLE...SO WILL LEAVE THAT IN THE FORECAST.
ALSO...TEMPERATURES LOOK TO REMAIN BELOW NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 120 AM EDT SUN AUG 2 2015
LOW-LEVEL DRY AIR WILL ALLOW VFR CONDITIONS TO CONTINUE OVERNIGHT AT
KIWD/KCMX/KSAW. AN APPROACHING DISTURBANCE SHOULD BEGIN TO SPREAD
SHRA AND SOME TS INTO THE AREA LATE TONIGHT WITH COVERAGE INCREASING
DURING THE MORNING. CONFIDENCE IN TS OCCURRING AT ANY OF THE
TERMINALS REMAINS LOW ENOUGH AT THIS POINT TO PRECLUDE A MENTION.
VFR CONDITIONS SHOULD CONTINUE TODAY...BUT IF THERE IS ANY MDT/HVY
RAINFALL...MVFR AND PERHAPS EVEN IFR CONDITIONS COULD OCCUR FOR A
VERY BRIEF TIME. SHRA WILL END NW TO SE IN THE LATE AFTN/EARLY
EVENING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 323 PM EDT SAT AUG 1 2015
A LOW SPINNING OVER SOUTHERN HUDSON BAY WILL SWEEP A PAIR OF TROFS
ACROSS LAKE SUPERIOR TONIGHT AND SUN. WINDS WILL GENERALLY BE IN THE
10-20KT RANGE. HI PRES FROM THE CANADIAN PRAIRIES WILL MOVE OVER THE
REGION THROUGH MOST OF NEXT WEEK...KEEPING WINDS UNDER 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...ROLFSON
MARINE...KC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
358 AM CDT SUN AUG 2 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
CHANCE FOR THUNDERSTORMS AND WARM TEMPERATURES TODAY...THEN OFF AND
ON STORM CHANCES THROUGH TUESDAY...ARE THE PRIMARY FORECAST CONCERNS.
SCATTERED THUNDERSTORMS POPPED UP EARLY THIS MORNING JUST AHEAD OF
MID LEVEL WAVE DROPPING SOUTHEAST THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA AS PER WATER VAPOR AND RAP ANALYSIS. THIS WAVE WILL
TRACK EAST OF OUR CWA EARLY IN THE DAYLIGHT HOURS...WITH SUBSIDENCE
BEHIND WAVE KEEPING MUCH OF THE REST OF THE MORNING DRY.
ANOTHER SHORTWAVE IN THE NORTHERN PLAINS INTO THE NORTHERN GREAT
LAKES IS FORECAST TO SWEEP SOUTHEAST LATER TODAY...WITH SURFACE
REFLECTION IN THE FORM OF A FRONT/WIND SHIFT SETTLING INTO NORTHEAST
NEBRASKA THIS AFTERNOON. SURFACE DEW POINTS NEAR OR ABOVE 70F AHEAD
OF THIS BOUNDARY ARE EXPECTED TO POOL IN EASTERN NEBRASKA AND
WESTERN IOWA DURING PEAK HEATING. CONVERGENCE ALONG BOUNDARY SHOULD
BE ENOUGH TO GET AT LEAST ISOLATED THUNDERSTORMS FIRING IN UNSTABLE
ATMOSPHERE CHARACTERIZED BY MUCAPES OVER 2500 J/KG. MEANWHILE
MODERATE MID LEVEL FLOW WILL HELP GENERATE NEAR 40KT OF BULK SHEAR
WITH VECTORS NORMAL TO SURFACE CONVERGENCE...SUGGESTING DISCRETE AND
ROTATING STORMS ARE LIKELY...SUPPORTING HAIL AND WIND POTENTIAL.
ONLY MARGINAL RISK IN SPC OUTLOOK...AND CAN NOT ARGUE GIVEN
EXPECTED SCANT COVERAGE. INITIATION LOOKS TO BE FARTHER NORTH THAN
PREVIOUS MODEL RUNS WITH LATER ARRIVAL OF FRONT...MOSTLY LIKELY
FIRING NEAR OR SOUTH OF A WAYNE TO ALBION LINE BETWEEN 3 AND 4 PM.
EXPECT ISOLATED TO SCATTERED STORMS TO PROGRESS SOUTH THROUGH THE
REST OF THE AFTERNOON INTO THE EVENING WITH FRONTAL BOUNDARY
BEFORE EXITING SOUTHEAST NEBRASKA AND SOUTHWEST AROUND MIDNIGHT
WHEN LAST OF 850 MOISTURE PLUME FINALLY DROPS SOUTH.
AHEAD OF FRONT...TEMPERATURES ARE EXPECTED WELL INTO THE 90S
ESPECIALLY IF CLOUD COVER FROM MORNING CONVECTION DISSIPATES AS
EXPECTED. WILL LIKELY SEE SOME HEAT INDICES TOPPING 100 FOR A COUPLE
OF HOURS THIS AFTERNOON.
SHOULD SEE A DRY PERIOD AFTER MIDNIGHT TONIGHT...BUT LOWERING
PRESSURES IN THE HIGH PLAINS WILL DRAW 850 MOISTURE BACK NORTH
RATHER QUICKLY BY LATER MONDAY MORNING AS NORTHWEST MID LEVEL FLOW
CONTINUES. WILL KEEP OUR SMALL POPS FOR OUR WESTERN CWA DURING THAT
TIME PERIOD...WITH CHANCES/COVERAGE GRADUALLY INCREASING MONDAY
AFTERNOON...BUT ESPECIALLY OVERNIGHT AND TUESDAY AS MAGNITUDE OF
MOISTURE RETURN INCREASES. WILL MAINTAIN 30 TO 50 PERCENT STORM
CHANCES DURING THE DAY TUESDAY. SEVERE THREAT SHOULD BE MINIMAL THEN
AS INSTABILITY REMAINS WEAK DUE TO MUCH COOLER SURFACE
TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
UNSETTLED WEATHER PATTERN WITH OCCASIONAL RAIN/STORM CHANCES WILL
CONTINUE THROUGH MUCH OF THE REST OF THE WEEK. MID LEVEL RIDGE IS
FORECAST TO REMAIN FROM TEXAS WEST TO THE SOUTHWESTERN STATES AT
LEAST THROUGH THURSDAY...KEEPING STORM TRACK ROLLING FROM THE
CENTRAL/NORTHERN ROCKIES ACROSS THE PLAINS. SEVERAL SHORTWAVES COULD
TRIGGER CONVECTION AT JUST ABOUT ANY TIME...WITH MORE POTENT WAVES
MOVING THROUGH OUR AREA WEDNESDAY DURING THE DAY AND THURSDAY
NIGHT AS PER ECMWF/GFS. WE SHOULD REMAIN ON THE COOL SIDE OF
SURFACE FRONTAL SYSTEM...SO INSTABILITY PROGS SUGGEST SEVERE
CHANCE WILL BE MINIMAL OVERALL WITH TEMPERATURES REMAINING IN THE
70S AND 80S MUCH OF THE WEEK.
&&
.AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1152 PM CDT SAT AUG 1 2015
NOT MUCH CHANGE FROM PREVIOUS THINKING. ISOLATED TSTMS POSSIBLE
THE NEXT 24 HOURS BUT CHANCES TOO LOW TO MENTION IN TAFS AT THIS
TIME. LOOK FOR VFR CONDITIONS WITH ANY CEILINGS EXPECTED TO BE
ABOVE 8000 FEET. BEST CHANCE OF TSRA WOULD BE WITH WIND SHIFT
SUNDAY AFTERNOON/EVENING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS ELKO NV
215 AM PDT SUN AUG 2 2015
.SYNOPSIS...MONSOON MOISTURE WILL INFLUENCE THE LOCAL REGION.
PORTIONS OF NORTHERN AND CENTRAL NEVADA WILL RECEIVE RAIN SHOWERS
AND THUNDERSTORMS TODAY. CONVECTION WILL LINGER THROUGH THE MIDDLE
OF THE WEEK THEN EXPECT DRIER CONDITIONS. TEMPERATURES WILL BE NEAR
NORMAL.
&&
.SHORT TERM...TODAY THROUGH MONDAY. THE LONGWAVE PATTERN FEATURES
RIDGING FROM NEW MEXICO TO WASHINGTON...WITH A PLUME OF MOISTURE
OVER THE EASTERN GREAT BASIN. THERE IS A WEAK VORTEX EMBEDDED IN THE
H5 FLOW...WHICH WILL ENABLE CONVECTION TO FLARE UP. THE CONVECTIVE
TEMPERATURE FOR ELKO AT 21Z IS 82F...WITH PWS CLIMBING ABOVE .75 OF
AN INCH. THE VORTEX IS MOVING AT A GLACIAL PACE AND WILL CONTINUE
TO BE THE MAIN EVENT WITH THIS MONSOON EPISODE. SIMILAR TO
YESTERDAY`S RUNS...THE NAM AND THE HRRR BOTH DEPICT MOIST AND
UNSTABLE AIR IMPACTING THE LKN CWA THIS FORECAST PERIOD...WITH THE
NAM BEING A BIT MORE AGGRESSIVE WITH THE QPF. THIS DISTURBANCE HAS
MULTIPLE IMPULSES ROTATING ABOUT...AND THE MODELS SHOW TWO
DISTINCT AREAS OF ACTIVITY...ONE PUSHING UP THROUGH CENTRAL
NV...AND THE OTHER IMPACTING WESTERN NV. FOR THE POPS THIS PACKAGE
...USED AN ALL BLEND WITH TERRAIN ENHANCEMENT. AS TIME ELAPSES
THIS PERTURBATION WILL SHIFT NORTHEASTWARD...SHIFTING THE QPF
FOCUS TO THE NORTHERN ZONES NEAR THE IDAHO BORDER ON MONDAY.
.LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. MODELS AGREE WELL ON
LARGE PICTURE OF SOUTHWEST RIDGE FLATTENING AND DRIFTING EAST AS
PACIFIC LOW MOVES INTO COAST. THIS COMBO PRODUCED A RELATIVELY DRY
AIRMASS WITH SPOTTY MOISTURE. BEST CHANCES FOR PRECIP ARE EARLY IN
THE PERIOD. TOOK OUT ONE PERIOD OF SHOWERS ONLY AND LEFT ALL
POTENTIAL CONVECTION AS -TRW. AIRMASS DRIES AS WEEK PROGRESSES SO
POPS AND THUNDER COVERAGE LOWER EACH PERIOD UNTIL LATE WHEN MODELS
BEGIN TO DIVERGE AGAIN AND SOME CONVECTION MAY FIRE AGAIN. WARMING
TREND WILL BE GENERAL AFTER A SLIGHT COOLING DUE TO CLOUDS AND
CONVECTION. IT IS THE DOG DAYS...AFTER ALL.
&&
.AVIATION...INCREASING SOUTHERLY MOISTURE WILL START A FEW VCSH
AROUND KTPH AND KELY. BY LATE MORNING...EXPECTING VCTS AT ALL SITES
WITH GUSTY ERRATIC WINDS. KWMC HAS A FEW ODD WIND SHIFTS LIKELY
RELATED TO LOCAL VIRGA WHICH ARE STIRRING UP DUST (HZ) AND SO HAVE
INCLUDED A TEMPO LOWER VISBY THIS MORNING. AS THE AFTERNOON
WARMS...THIS SHOULD IMPROVE. STORMS/SHOWERS PERSIST INTO EARLY
EVENING BEFORE WANING. A FEW SHOWERS IN CENTRAL AND EASTERN NEVADA
COULD BE BRIEFLY HEAVY.
&&
.FIRE WEATHER...THE NAM PLACES THE BEST LI`S SQUARELY OVER 454
THIS MORNING AND THEN SHIFTING TO THE NORTH THIS AFTERNOON. WHILE
THE MODELS ARE IN GOOD AGREEMENT ABOUT THE GENERAL PATTERN...THE
OVERALL CONFIDENCE HAS TO BE TEMPERED WITH THE LACK OF AGREEMENT
IN THE SMALL DETAILS. GENERALLY EXPECTING A CONVECTIVE PATTERN
TODAY...WETTING RAINS POSSIBLE. ANOTHER ROUND OF TSRA IS EXPECTED
ON MONDAY.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
97/98/98/97
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1146 PM MDT SAT AUG 1 2015
.AVIATION...
06Z TAF CYCLE
MESOSCALE MODELS DEPICT A BROAD AREA OF LIGHT TO MODERATE TS/SHRA
PERSISTING INTO THE EARLY MORNING HOURS ACROSS CENTRAL NM FROM THE
CONTDVD TO THE CENTRAL MT CHAIN. THIS SHOULD IMPACT MAINLY THE
MIDDLE AND LOWER RIO GRANDE VALLEY...BUT COULD TRACK NORTHWARD TO
AROUND SANTA FE. ANOTHER ROUND OF SCT TO NMRS TS/SHRA IS PROGGED
TO IMPACT MUCH OF THE FORECAST AREA SUNDAY AFTN/EVENING WITH
LOWEST PROBABILITIES AT KROW AND HIGHEST PROBABILITIES AT
KGUP...KFMN...KSAF AND KLVS.
44
&&
.PREV DISCUSSION...952 PM MDT SAT AUG 1 2015...
.UPDATE...
HEAVY RAIN THREAT IS ENDING ACROSS N/C NEW MEXICO. MAINLY
STRATIFORM TYPE OF EVENT WITH EMBEDDED CONVECTION DURING THE REST
OF THE OVERNIGHT. LOOKS LIKE THE MAIN BAND ACROSS WESTERN/CENTRAL
NM SHOULD SHIFT NORTHWARD DURING THE OVERNIGHT ALTHOUGH MAY JUST
DIE OUT OVER CENTRAL AREAS. UPDATED POPS AND ENDED THE FLASH
FLOOD WATCH.
50
&&
.PREV DISCUSSION...332 PM MDT SAT AUG 1 2015...
.SYNOPSIS...
AN ACTIVE MONSOON PATTERN IS EXPECTED TO PERSIST THROUGH THE
REMAINDER OF THE WEEKEND. SLOW-MOVING STORMS CAPABLE OF PRODUCING
TORRENTIAL RAINFALL AND FLASH FLOODING WILL REMAIN A CONCERN THIS
AFTERNOON AND EARLY TONIGHT AND AGAIN SUNDAY...ESPECIALLY IN NORTH
CENTRAL TO NORTHWEST PARTS OF NEW MEXICO. DRIER AND MORE STABLE
AIR WILL ATTEMPT TO WORK WEST BEGINNING MONDAY...SIGNIFICANTLY
LOWERING THE OVERALL COVERAGE OF STORMS AND FLASH FLOOD THREAT.
FEWER STORMS WILL TRANSLATE INTO A DAY TO DAY WARMING TREND NEXT
WEEK...AS WELL.
&&
.DISCUSSION...
SLOW-MOVING THUNDERSTORMS HAVE BEEN FOCUSED SQUARELY WITHIN THE
FLASH FLOOD WATCH THUS FAR...WITH TREMENDOUSLY IMPRESSIVE RAINFALL
RATES AS HIGH AS 3.3 INCHES PER HOUR AS MEASURED BY A PERSONAL
WEATHER STATION ON THE NORTHWEST SIDE OF SANTA FE. GENERALLY 1 TO
3 INCH PER HOUR RATES LIKELY WITH JUST ABOUT ANY WELL-DEVELOPED
STORM. MAY CONSIDER EXPANDING WATCH TO INCLUDE NE/EC AREAS
ALTHOUGH COVERAGE EAST OF THE CENTRAL MOUNTAIN CHAIN SHOULD BE
MORE ISOLATED TO SCATTERED. BUT RECENT RUNS OF THE HRRR CONTINUE
TO SUGGEST SMALL MCS-LIKE FEATURE ORGANIZING BETWEEN CLAYTON AND
CONCHAS DAM ROLLING TOWARD TUCUMCARI-LOGAN LATER THIS EVENING.
THIS WOULD ONE AREA OF CONCERN GIVEN VERY HEAVY RAIN PAST TWO
DAYS. WEAKNESS IN THE 500MB RIDGE NEAR THE NM/CO LINE ALSO A
PLAYER BUT VERY DIFFICULT TO TRACK BEYOND 12 HOURS.
OTHERWISE...WE`RE NOW MOVING INTO OUTFLOW BOUNDARY INTERACTION
TIME OF DAY FOR VALLEY LOCATIONS CENTRAL/WEST. AIR MASS PLENTY
MOIST WITH PRECIPITABLE WATER VALUES RANGING FROM 1.2 INCHES NW
TO 1.5 INCHES NEAR THE NM/TX LINE. A POCKET OF RELATIVELY LOWER
PWAT AIR /ONE 1 INCH OR SLIGHTLY LESS/ ANALYZED OVER THE LOWER RIO
GRANDE VALLEY TO UPPER GILA HAS KEPT COVERAGE A BIT LOWER THERE
BUT SUBTLE GRADIENTS.
GOING INTO SUNDAY...VERY LITTLE CHANGE TO OVERALL ORIENTATION OF
THE MONSOON PLUME BENEATH VERY WEAK STEERING CURRENTS. LEAST
FAVORED REGION WILL CONTINUE TO BE THE SOUTHEAST CORNER...WHILE
NC TO WC AREAS AGAIN FAVORED IN ADDITION TO THE SW THAT COULD SEE
A BUMP IN COVERAGE AS COMPARED TO TODAY.
THEREAFTER...WE HAVE BEGUN TO REFLECT A MARKED DECREASE IN STORM
COVERAGE MONDAY AND ESPECIALLY TUESDAY THROUGH THURSDAY. THIS AS
THE ANTICYCLONIC BELT OF WESTERLIES ELONGATES WEST-EAST AND SHIFTS
SLIGHTLY SOUTH PLACING THE AREA UNDER A DRIER WESTERLY FLOW
REGIME. THAT SAID...THE LAST DRYING EPISODE WAS POORLY HANDLED BY
VIRTUALLY ALL THE NWP MODELS AS THEY TEND TO DRY OUR MOIST
RESIDENT AIR MASS TOO QUICKLY. SO WE WILL PROCEED WITH A LITTLE
PRUDENCE...BUT DEFINITELY TRENDING FORECAST TOWARD MUCH FEWER
STORMS NEXT WEEK. IF THE MODELS ARE CORRECT WE WILL STRUGGLE TO
DEVELOP A STORM ANYWHERE BY MID- WEEK. THAT IN TURN WILL ALLOW FOR
A DAY TO DAY WARMING TREND. COULD SEE OUR NEXT BACKDOOR SURGE
THUR/FRI THEN WE START THE MOISTENING CYCLE OVER. KJ
&&
.FIRE WEATHER...
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL FOCUS ON
NORTHERN AND WESTERN NEW MEXICO TODAY AND SUNDAY...WITH FURTHER
DEVELOPMENT EAST OF THE CENTRAL MOUNTAIN CHAIN. STEERING FLOW FROM
THE UPPER LEVEL HIGH RECENTERING OVER THE SOUTHERN PORTION OF THE
STATE WILL STEER SLOW MOVING NORTH TO NORTHEAST STORMS ACROSS
NORTHWESTERN TO NORTH CENTRAL AREAS WHERE FLASH FLOODING WILL
CONTINUE TO BE A MAJOR CONCERN THROUGHOUT THE REMAINDER OF THE
WEEKEND.
LOOK FOR A DRIER AIR MASS TO FILTER INTO THE STATE MONDAY THROUGH
THURSDAY AS THE UPPER LEVEL HIGH OVER SOUTHERN NEW MEXICO SHIFTS
WESTWARD FILTERING IN DRIER AIR FROM THE PACIFIC. SHOWER AND
THUNDERSTORM ACTIVITY WILL DOWNTREND AS TEMPERATURES CREEP BACK TO
NORMAL/ABOVE NORMAL READINGS. EXPECT HAINES VALUES TO INCREASE TO
THE 5 AND 6 VALUES ALONG WITH DECREASING MIN RH VALUES. STORM
ACTIVITY WILL BE LIMITED TO HIGHER TERRAIN AREAS AND ADJACENT LOWER
ELEVATION AREAS. THE MOISTURE PLUME LOOKS TO MAKE ITS RETURN BY THE
FOLLOWING WEEKEND WITH AN INCREASE IN WETTING PRECIPITATION CHANCES
ACROSS THE WEST AND NORTH AS THE UPPER LEVEL HIGH STARTS TO SHIFT
EASTWARD.
EXPECT POOR VENT RATES ACROSS THE NORTH THE REMAINDER OF THE WEEKEND
WITH IMPROVEMENTS BY MONDAY THROUGH THURSDAY. MIN RH VALUES WILL
DROP INTO THE UPPER TEENS BY THE MIDWEEK BUT OVERNIGHT RECOVERIES
WILL REMAIN GOOD. 32
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 AM EDT SUN AUG 2 2015
.SYNOPSIS...
A WEAK FRONT WILL REMAIN STALLED ACROSS THE COASTAL CAROLINAS...
PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS NEAR THE COAST. THE
FRONT SHOULD DISSIPATE ON MONDAY. BERMUDA HIGH PRESSURE WELL
OFFSHORE WILL BUILD WESTWARD THIS WEEK. TEMPERATURES WILL REMAIN
SEASONABLE TO SLIGHTLY ABOVE NORMAL THROUGH THE WEEKEND INTO NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1000 PM SATURDAY...FORECAST SOUNDINGS FROM BOTH THE NAM AND
GFS SHOW A THIN LAYER OF UNSTABLE AIR AT THE TOP OF TODAY`S DEEP
MIXED LAYER ACROSS THE PEE DEE REGION. THIS IS NOT A SITUATION I
WOULD HAVE ANTICIPATED CONVECTION TO DEVELOP WITHIN GIVEN ELEVATED
INSTABILITY BASED AROUND 6500 FEET AGL AND BONE-DRY AIR AT AND
ABOVE 700 MB. NEVERTHELESS THERE ARE SHOWERS WITH LOCALLY HEAVY
RAIN DEVELOPING ALONG THE I-95 CORRIDOR FROM FLORENCE NORTHWARD TO
NEAR BINGHAM IN WESTERN DILLON COUNTY. INFRARED SATELLITE SHOWS
ADDITIONAL MID- LEVEL CLOUD COVER EXTENDING NORTHWARD INTO ROBESON
COUNTY NC...SO I HAVE TO AT LEAST CONSIDER THE POSSIBILITY FOR
SHOWERS TO DEVELOP THIS FAR NORTH AS WELL.
AT THE SURFACE HIGHER DEWPOINTS HAVE RETURNED WESTWARD INTO THE
INTERIOR COASTAL PLAIN WITH 70S SHOWING UP AGAIN IN LUMBERTON...
MARION AND FLORENCE. THIS MOISTURE MAY BE TOO THIN TO BE FEEDING
THE CONVECTION DIRECTLY...AS THE SURFACE IS LIKELY DECOUPLED FROM
THE ATMOSPHERE ALOFT.
LATEST HRRR MODEL RUNS DO NOT REALLY SHOW THIS CURRENT ACTIVITY
WELL...ALTHOUGH INTERESTINGLY THE 00Z NAM DOES. THE NAM MOVES THE
SHOWERS EASTWARD TOWARD THE COAST...DISSIPATING THE CONVECTION
BETWEEN 06-09Z NEAR MYRTLE BEACH.
AT 500 MB THE CAROLINAS FORM THE BASE OF A BROAD TROUGH EXTENDING
DOWN FROM HUDSON BAY CANADA. PLENTY OF DRY AIR AT AND ABOVE 700 MB
SHOULD CONTINUE ON WESTERLY WINDS OVERNIGHT. HIGH PRESSURE OVER
THE OHIO VALLEY WILL DRIFT EASTWARD INTO THE CENTRAL APPALACHIANS
SUNDAY MORNING. THIS WILL NUDGE OUR FRONT OFF THE COAST INTO THE
NEARSHORE WATERS BY DAYBREAK. MOISTURE TRAPPED WITHIN THE
DECOUPLED BOUNDARY LAYER WILL REMAIN TRAPPED OVERNIGHT...AND WITH
GOOD RADIATIONAL COOLING I ANTICIPATE PATCHY FOG WILL
DEVELOP...ESPECIALLY EAST OF I-95 WHERE DEWPOINTS ARE HIGHEST.
LOWS SHOULD FALL 70-74...WARMEST AT THE BEACHES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...STATIONARY FRONT WILL REMAIN IN AREA
SUNDAY BEFORE DISSIPATING IN PLACE ON MONDAY. MEANWHILE...A
BROAD...FLAT-ISH H5 TROUGH WILL REMAIN ANCHORED IN PLACE OVER
EASTERN CONUS. GUIDANCE STILL SHOWING PLENTIFUL DRY AIR ALOFT
WHICH WILL LIMIT EXTENT OF CONVECTION DESPITE PRESENCE OF FRONTAL
BOUNDARY AND THE OCCASIONAL SHORT WAVE THAT WILL DROP INTO THE
BASE OF THE UPPER TROUGH. AIR ALOFT IS DRIEST INLAND...SO WILL
SHOW A DECREASING GRADIENT IN POPS NW FROM THE COAST FOR BOTH
DAYS. DUE TO OVERALL LIMITED MOISTURE ALOFT...WILL KEEP POPS
CAPPED AT LOW CHANCE FOR THE IMMEDIATE COAST FOR BOTH DAYS...WITH
FAR INLAND AREAS BEING POSSIBLY TOO DRY TO SEE ANY SIGNIFICANT
RAINFALL.
TEMPERATURES WILL REMAIN ABOVE CLIMO THROUGH THE SHORT TERM AND
HEAT INDEX VALUES WILL LIKELY REACH AROUND A 100 OR SO BOTH
AFTERNOONS. HOWEVER...HEAT ADVISORY CRITERIA IS NOT EXPECTED TO
BE EXCEEDED.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...WHAT LITTLE MOISTURE THERE WILL BE IN
PLACE ON TUESDAY WILL BE POOLED UP ALONG THE COAST. MINOR RAIN
CHANCES WILL BE FOCUSED THERE DURING AN OTHERWISE HOT AFTERNOON
PROVIDED IN PART BY A VERY WEAK RIDGE ALOFT. RAIN CHANCES REMAIN
SLOW ON WEDNESDAY AS THE FLOW ALOFT STAYS WEAK THOUGH THE SENSE OF
RIDGING WEAKENS. SO WILL KEEP POPS MINIMIZED BUT SHOW THEM AREA-
WIDE. RAIN CHANCES RAMP UP TO SCATTERED ON THURSDAY AS SOME WEAKLY
CYCLONIC CURVATURE OVERSPREADS THE REGION AND A SURFACE PIEDMONT
TROUGH TAKES SHAPE. ANOTHER LITTLE PIECE OF ENERGY WILL PROVIDE
SOME LIFT ON FRIDAY WHICH MAY BE ANOTHER FAIRLY ACTIVE DAY. ON
SATURDAY NOT ONLY WILL THERE BE CONTINUED DISTURBANCES IMPINGING
UPON THE AREA FROM THE NORTHWEST BUT A COLD FRONT WILL ALSO BE
MOVING INTO THE CAROLINAS. WEDNESDAY AND THURSDAY WILL BOTH SEE
RATHER HOT AFTERNOONS WHEREAS THE INCREASE IN CLOUDS LATE IN THE
PERIOD SHOULD TEMPER THINGS A BIT BACK TOWARDS CLIMO.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...EARLIER CONVECTION HAS DISSIPATED ACROSS THE CWA AND
SKIES HAVE TRENDED CLEAR FOR THE MOST PART. WITH SUFFICIENT LOW-
LEVEL MOISTURE...AN INVERSION AND LIGHT WINDS...PATCHY FOG
IS FORECAST ACROSS THE INLAND TERMINALS WITH MVFR VSBY BETWEEN
09-12Z. MAIN WEATHER FEATURE FOR TODAY WILL BE THE STATIONARY
FRONT/SEA BREEZE WHICH WILL TRIGGER ISOLATED SHOWERS OR TSTMS
ACROSS THE COASTAL TERMINALS THIS AFTERNOON AND EVE. WILL KEEP VFR
AT ALL THE TERMINALS...BUT CANNOT RULE OUT BRIEF MVFR VSBY/
CEILING IF CONVECTION OCCURS DIRECTLY OVER KILM/KCRE/KMYR.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH A
SLIGHT CHANCE AFTERNOON SHRA/TSRA.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 PM SATURDAY...A FRONT IS STALLED ACROSS THE COASTAL
PLAIN OF THE CAROLINAS THIS EVENING. HIGH PRESSURE OVER OHIO WILL
DRIFT EAST INTO THE CENTRAL APPALACHIANS LATE TONIGHT. THIS SHOULD
NUDGE THE FRONT EASTWARD AND INTO THE COASTAL WATERS LATE. SOUTH
TO SOUTHWEST WINDS THIS EVENING AS HIGH AS 15 KNOTS IN THE CAPE
FEAR AREA SHOULD DIMINISH TO LESS THAN 10 KNOTS AFTER
MIDNIGHT...THEN TURN NORTHWESTERLY LATE AS THE FRONT PUSHES OFF
THE COAST.
THE PRIMARY WAVE SET IS A 7-SECOND SOUTHERLY SWELL...WITH A
SMALLER 10-SECOND SOUTHEASTERLY SWELL SHOWING UP. THESE TWO WAVES
WILL CONTINUE INDEPENDENT OF THE WIND OVERNIGHT...WITH COMBINED
SEAS 2-4 FEET...HIGHEST OFFSHORE FROM CAPE FEAR.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...A STALLED FRONT WILL DISSIPATE OVER THE
EASTERN CAROLINAS ON MONDAY AS BERMUDA HIGH PRESSURE OFFSHORE
EXTENDS BACK WEST ACROSS THE WATERS. WINDS WILL SETTLE BACK INTO A
SWLY DIRECTION BY SUNDAY NIGHT AS THE FRONT WEAKENS AND
DISSIPATES. A SMALL CRAFT ADVISORY MAY BE REQUIRED MONDAY
AFTERNOON OR EVENING AS THE GRADIENT TIGHTENS WITH HIGH PRESSURE
BUILDING WEST ACROSS THE WATERS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...WIND AND SEAS RELAX ON TUESDAY AS
PIEDMONT TROUGHINESS PUSHES THE TIGHTER GRADIENT CAUSED BY THE
BERMUDA HIGH FURTHER OUT TO SEA. THOUGH SOME SWELL ENERGY MAY
REMAIN WE SHOULD DROP BELOW ADVISORY THRESHOLDS. THEREAFTER IT
LOOKS LIKE PRETTY STANDARD FARE FOR JULY WITH A SOUTHWESTERLY WIND
IN THE 10 TO 15 KT RANGE AND 2 TO 4 FT SEAS...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 200 AM SATURDAY...MINOR COASTAL FLOODING IS POSSIBLE DURING
THE NIGHT-TIME HIGH TIDE OVER THE NEXT COUPLE OF DAYS. THESE
HIGHER THAN NORMAL TIDES ARE THE RESULT OF THE PERIGEAN SPRING
TIDE AND A FULL MOON WHICH OCCURRED ON FRIDAY. DEPARTURES OF PLUS
1/2 TO 1 FOOT WILL BE ENOUGH TO PRODUCE A BRIEF PERIOD OF MINOR
COASTAL FLOODING. THE RISK IS HIGHEST FOR PORTIONS OF THE LOWER
CAPE FEAR RIVER TO INCLUDE DOWNTOWN WILMINGTON...WITH A LIKELY
PROBABILITY. THE BEACHES WILL APPROACH THE THRESHOLD FOR MINOR
COASTAL FLOODING AGAIN THIS EVE...BUT THIS WILL BE THE LAST TIME
THIS LUNAR CYCLE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...REK
LONG TERM...MBB
AVIATION...MAC/RJD
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1204 AM EDT SUN AUG 2 2015
.SYNOPSIS...
A WEAK FRONT WILL REMAIN STALLED ACROSS THE COASTAL CAROLINAS...
PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS NEAR THE COAST. THE
FRONT SHOULD DISSIPATE ON MONDAY. BERMUDA HIGH PRESSURE WELL
OFFSHORE WILL BUILD WESTWARD THIS WEEK. TEMPERATURES WILL REMAIN
SEASONABLE TO SLIGHTLY ABOVE NORMAL THROUGH THE WEEKEND INTO NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1000 PM SATURDAY...FORECAST SOUNDINGS FROM BOTH THE NAM AND
GFS SHOW A THIN LAYER OF UNSTABLE AIR AT THE TOP OF TODAY`S DEEP
MIXED LAYER ACROSS THE PEE DEE REGION. THIS IS NOT A SITUATION I
WOULD HAVE ANTICIPATED CONVECTION TO DEVELOP WITHIN GIVEN ELEVATED
INSTABILITY BASED AROUND 6500 FEET AGL AND BONE-DRY AIR AT AND
ABOVE 700 MB. NEVERTHELESS THERE ARE SHOWERS WITH LOCALLY HEAVY
RAIN DEVELOPING ALONG THE I-95 CORRIDOR FROM FLORENCE NORTHWARD TO
NEAR BINGHAM IN WESTERN DILLON COUNTY. INFRARED SATELLITE SHOWS
ADDITIONAL MID- LEVEL CLOUD COVER EXTENDING NORTHWARD INTO ROBESON
COUNTY NC...SO I HAVE TO AT LEAST CONSIDER THE POSSIBILITY FOR
SHOWERS TO DEVELOP THIS FAR NORTH AS WELL.
AT THE SURFACE HIGHER DEWPOINTS HAVE RETURNED WESTWARD INTO THE
INTERIOR COASTAL PLAIN WITH 70S SHOWING UP AGAIN IN LUMBERTON...
MARION AND FLORENCE. THIS MOISTURE MAY BE TOO THIN TO BE FEEDING
THE CONVECTION DIRECTLY...AS THE SURFACE IS LIKELY DECOUPLED FROM
THE ATMOSPHERE ALOFT.
LATEST HRRR MODEL RUNS DO NOT REALLY SHOW THIS CURRENT ACTIVITY
WELL...ALTHOUGH INTERESTINGLY THE 00Z NAM DOES. THE NAM MOVES THE
SHOWERS EASTWARD TOWARD THE COAST...DISSIPATING THE CONVECTION
BETWEEN 06-09Z NEAR MYRTLE BEACH.
AT 500 MB THE CAROLINAS FORM THE BASE OF A BROAD TROUGH EXTENDING
DOWN FROM HUDSON BAY CANADA. PLENTY OF DRY AIR AT AND ABOVE 700 MB
SHOULD CONTINUE ON WESTERLY WINDS OVERNIGHT. HIGH PRESSURE OVER
THE OHIO VALLEY WILL DRIFT EASTWARD INTO THE CENTRAL APPALACHIANS
SUNDAY MORNING. THIS WILL NUDGE OUR FRONT OFF THE COAST INTO THE
NEARSHORE WATERS BY DAYBREAK. MOISTURE TRAPPED WITHIN THE
DECOUPLED BOUNDARY LAYER WILL REMAIN TRAPPED OVERNIGHT...AND WITH
GOOD RADIATIONAL COOLING I ANTICIPATE PATCHY FOG WILL
DEVELOP...ESPECIALLY EAST OF I-95 WHERE DEWPOINTS ARE HIGHEST.
LOWS SHOULD FALL 70-74...WARMEST AT THE BEACHES.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...STATIONARY FRONT WILL REMAIN IN AREA
SUNDAY BEFORE DISSIPATING IN PLACE ON MONDAY. MEANWHILE...A
BROAD...FLAT-ISH H5 TROUGH WILL REMAIN ANCHORED IN PLACE OVER
EASTERN CONUS. GUIDANCE STILL SHOWING PLENTIFUL DRY AIR ALOFT
WHICH WILL LIMIT EXTENT OF CONVECTION DESPITE PRESENCE OF FRONTAL
BOUNDARY AND THE OCCASIONAL SHORT WAVE THAT WILL DROP INTO THE
BASE OF THE UPPER TROUGH. AIR ALOFT IS DRIEST INLAND...SO WILL
SHOW A DECREASING GRADIENT IN POPS NW FROM THE COAST FOR BOTH
DAYS. DUE TO OVERALL LIMITED MOISTURE ALOFT...WILL KEEP POPS
CAPPED AT LOW CHANCE FOR THE IMMEDIATE COAST FOR BOTH DAYS...WITH
FAR INLAND AREAS BEING POSSIBLY TOO DRY TO SEE ANY SIGNIFICANT
RAINFALL.
TEMPERATURES WILL REMAIN ABOVE CLIMO THROUGH THE SHORT TERM AND
HEAT INDEX VALUES WILL LIKELY REACH AROUND A 100 OR SO BOTH
AFTERNOONS. HOWEVER...HEAT ADVISORY CRITERIA IS NOT EXPECTED TO
BE EXCEEDED.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...WHAT LITTLE MOISTURE THERE WILL BE IN
PLACE ON TUESDAY WILL BE POOLED UP ALONG THE COAST. MINOR RAIN
CHANCES WILL BE FOCUSED THERE DURING AN OTHERWISE HOT AFTERNOON
PROVIDED IN PART BY A VERY WEAK RIDGE ALOFT. RAIN CHANCES REMAIN
SLOW ON WEDNESDAY AS THE FLOW ALOFT STAYS WEAK THOUGH THE SENSE OF
RIDGING WEAKENS. SO WILL KEEP POPS MINIMIZED BUT SHOW THEM AREA-
WIDE. RAIN CHANCES RAMP UP TO SCATTERED ON THURSDAY AS SOME WEAKLY
CYCLONIC CURVATURE OVERSPREADS THE REGION AND A SURFACE PIEDMONT
TROUGH TAKES SHAPE. ANOTHER LITTLE PIECE OF ENERGY WILL PROVIDE
SOME LIFT ON FRIDAY WHICH MAY BE ANOTHER FAIRLY ACTIVE DAY. ON
SATURDAY NOT ONLY WILL THERE BE CONTINUED DISTURBANCES IMPINGING
UPON THE AREA FROM THE NORTHWEST BUT A COLD FRONT WILL ALSO BE
MOVING INTO THE CAROLINAS. WEDNESDAY AND THURSDAY WILL BOTH SEE
RATHER HOT AFTERNOONS WHEREAS THE INCREASE IN CLOUDS LATE IN THE
PERIOD SHOULD TEMPER THINGS A BIT BACK TOWARDS CLIMO.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 23Z...LATEST SFC ANALYSIS SHOWS A STATIONARY FRONT DRAPED
BETWEEN THE INLAND AND COASTAL TERMINALS. CONVECTION FIRED UP
ALONG THIS BOUNDARY MAINLY NEAR AND OVER KILM THIS AFTERNOON.
PLENTY OF LLVL MOISTURE AVAILABLE FOR THE TONIGHT/OVERNIGHT PERIOD
TRAPPED BENEATH AN INVERSION AND WITH LIGHT WINDS ALSO EXPECTED
CANNOT RULE OUT MVFR CONDITIONS DUE TO FOG
DEVELOPMENT...ESPECIALLY KILM. WILL MAKE MENTION AFTER 08Z IN ALL
TERMINALS FOR FOG AND MVFR CONDITIONS. VFR TO RETURN AFTER 12Z AND
SUNDAY WILL BE SOMEWHAT LIKE TODAY WITH THE STATIONARY FRONT
DRAPED ACROSS THE REGION AND THE CHANCE OF ISOLATED SHOWER OR
THUNDERSTORM POSSIBLE DURING THE DAY. WILL KEEP VFR IN ALL
TERMINALS BUT CANNOT RULE OUT A BRIEF MVFR IN VSBY/CEILING IF
CONVECTION OCCURS OVER A TERMINAL.
EXTENDED OUTLOOK...PREDOMINANTLY VFR THROUGH THE PERIOD WITH A
SLIGHT CHANCE AFTERNOON SHRA/TSRA.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 PM SATURDAY...A FRONT IS STALLED ACROSS THE COASTAL
PLAIN OF THE CAROLINAS THIS EVENING. HIGH PRESSURE OVER OHIO WILL
DRIFT EAST INTO THE CENTRAL APPALACHIANS LATE TONIGHT. THIS SHOULD
NUDGE THE FRONT EASTWARD AND INTO THE COASTAL WATERS LATE. SOUTH
TO SOUTHWEST WINDS THIS EVENING AS HIGH AS 15 KNOTS IN THE CAPE
FEAR AREA SHOULD DIMINISH TO LESS THAN 10 KNOTS AFTER
MIDNIGHT...THEN TURN NORTHWESTERLY LATE AS THE FRONT PUSHES OFF
THE COAST.
THE PRIMARY WAVE SET IS A 7-SECOND SOUTHERLY SWELL...WITH A
SMALLER 10-SECOND SOUTHEASTERLY SWELL SHOWING UP. THESE TWO WAVES
WILL CONTINUE INDEPENDENT OF THE WIND OVERNIGHT...WITH COMBINED
SEAS 2-4 FEET...HIGHEST OFFSHORE FROM CAPE FEAR.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...A STALLED FRONT WILL DISSIPATE OVER THE
EASTERN CAROLINAS ON MONDAY AS BERMUDA HIGH PRESSURE OFFSHORE
EXTENDS BACK WEST ACROSS THE WATERS. WINDS WILL SETTLE BACK INTO A
SWLY DIRECTION BY SUNDAY NIGHT AS THE FRONT WEAKENS AND
DISSIPATES. A SMALL CRAFT ADVISORY MAY BE REQUIRED MONDAY
AFTERNOON OR EVENING AS THE GRADIENT TIGHTENS WITH HIGH PRESSURE
BUILDING WEST ACROSS THE WATERS.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...WIND AND SEAS RELAX ON TUESDAY AS
PIEDMONT TROUGHINESS PUSHES THE TIGHTER GRADIENT CAUSED BY THE
BERMUDA HIGH FURTHER OUT TO SEA. THOUGH SOME SWELL ENERGY MAY
REMAIN WE SHOULD DROP BELOW ADVISORY THRESHOLDS. THEREAFTER IT
LOOKS LIKE PRETTY STANDARD FARE FOR JULY WITH A SOUTHWESTERLY WIND
IN THE 10 TO 15 KT RANGE AND 2 TO 4 FT SEAS...HIGHEST OFFSHORE.
&&
.TIDES/COASTAL FLOODING...
AS OF 200 AM SATURDAY...MINOR COASTAL FLOODING IS POSSIBLE DURING
THE NIGHT-TIME HIGH TIDE OVER THE NEXT COUPLE OF DAYS. THESE
HIGHER THAN NORMAL TIDES ARE THE RESULT OF THE PERIGEAN SPRING
TIDE AND A FULL MOON WHICH OCCURRED ON FRIDAY. DEPARTURES OF PLUS
1/2 TO 1 FOOT WILL BE ENOUGH TO PRODUCE A BRIEF PERIOD OF MINOR
COASTAL FLOODING. THE RISK IS HIGHEST FOR PORTIONS OF THE LOWER
CAPE FEAR RIVER TO INCLUDE DOWNTOWN WILMINGTON...WITH A LIKELY
PROBABILITY. THE BEACHES WILL APPROACH THE THRESHOLD FOR MINOR
COASTAL FLOODING AGAIN THIS EVE...BUT THIS WILL BE THE LAST TIME
THIS LUNAR CYCLE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...REK
LONG TERM...MBB
AVIATION...MAC
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1222 AM CDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1221 AM CDT SUN AUG 2 2015
A LINE OF THUNDERSTORMS CONTINUED MOVING SOUTH OUT OF
MANITOBA INTO NORTHEASTERN NORTH DAKOTA AND NORTHERN MINNESOTA. THIS
CONVECTION WAS ASSOCIATED WITH AN UPPER LEVEL VORT ENERGY IMPULSE
MOVING THROUGH THE NORTHWEST FLOW ALOFT IN THAT AREA...ALONG WITH A
SURFACE FRONT MOVING SOUTH ACROSS NORTH DAKOTA. THE WESTERN EDGE OF
THE CONVECTION WAS AS FAR WEST AS BOTTINEAU COUNTY...AND HAVE
INCREASED COVERAGE OF SLIGHT CHANCE OF THUNDERSTORMS DUE TO THE MORE
ISOLATED NATURE OF THE CELLS ON THE WESTERN EDGE OF THIS
DISTURBANCE. BULK SHEAR IS STILL QUITE HIGH...WITH THE BEST MIXED
LAYER CAPE OVER EASTERN NORTH DAKOTA. EXPECT RAIN SHOWERS/THUNDER TO
SKIM THE BOTTINEAU/TURTLE MOUNTAIN AREA...AND INTO RUGBY/TOWNER -
MAINLY EAST OF MINOT. SHORT TERM MODELS DIFFER ON HOW LONG
CONVECTION WILL LINGER...BUT ALL AGREE ON ACTIVITY REMAINING UNTIL
AROUND 09Z (4 AM CDT). THUS HAVE A MENTION OF ISOLATED STORMS UNTIL
THEN. WILL RE-EVALUATE LATER TO SEE WHICH OF THE MODELS HANDLED
CONVECTION THE BEST.
UPDATE ISSUED AT 853 PM CDT SAT AUG 1 2015
CONVECTION THREAT HAS ENDED OVER SOUTHEAST NORTH DAKOTA. FOCUS NOW
SHIFTS TO THE NORTH. ISOLATED CONVECTION OVER THE PAST HOUR OR SO
OVER SOUTHERN MANITOBA/SASKATCHEWAN IS BEGINNING TO PUSH INTO
NORTHERN NORTH DAKOTA. AN ISOLATED THUNDERSTORM DEVELOPED OVER
BOTTINEAU COUNTY OVER THE PAST HOUR. ML CAPES AROUND 1000-1500
J/KG WITH 50-60 KNOTS OF BULK SHEAR REMAIN OVER THE FAR NORTH
CENTRAL INTO THE TURTLE MOUNTAINS AND A FEW MORE STORMS CAN NOT BE
RULED OUT OVER THE NEXT FEW HOURS. THE THREAT FOR SEVERE WEATHER
WILL BE MINIMAL...AND WILL SHIFT FARTHER EAST AS THE EVENING
PROGRESSES. THIS IS CURRENTLY COVERED IN THE GOING FORECAST.
WE DID BUMP UP WINDS OVER THE WEST AND CENTRAL THIS EVENING
A NICE FALL-RISE PRESSURE BUBBLE WAS NOTED OVER THE NORTHWEST
ASSOCIATED WITH THE SURFACE LOW OVER NORTHWEST NORTH DAKOTA. SOME
40 MPH WIND GUSTS WERE REPORTED OVER THE FAR NORTHWEST WITH THE 8
PM OBSERVATIONS. THE COUPLET WILL TRACK SOUTHEAST ACROSS THE
FORECAST AREA TONIGHT. BUT AS WINDS DECOUPLE THIS EVENING WITH THE
SETTING SUN...THE STRONGER GUST POTENTIAL WILL ALSO SUBSIDE.
UPDATE ISSUED AT 543 PM CDT SAT AUG 1 2015
UNSTABLE AIRMASS REMAINS OVER SOUTHEAST NORTH DAKOTA.
HOWEVER...THERE HAS BEEN ENOUGH CIN TO PRECLUDE THUNDERSTORM
DEVELOPMENT FROM CU FIELD THAT DEVELOPED EARLIER THIS AFTERNOON.
CAPE REMAINS HIGH BUT SHEAR IS DECREASING. WILL KEEP A MENTION OF
THUNDER THROUGH 7 PM AS A FEW CU REMAIN OVER CENTRAL AND EASTERN
PORTIONS OF DICKEY/LAMOURE COUNTIES.
TO THE NORTHWEST...A LINE OF CU HAS DEVELOPED ALONG THE COLD FRONT
MOVING INTO NORTHWEST NORTH DAKOTA. SUFFICIENT BULK SHEAR ALONG
THE INTERNATIONAL BORDER BUT DEEP MOISTURE IS LACKING...ESPECIALLY
RIGHT ALONG AND BEHIND THE FRONT WITH MUCH DRIED DEWPOINTS OVER
THE FAR NORTHWEST AND INTO NORTHEAST NORTH DAKOTA. COULD STILL BE
SOME SHOWER/THUNDERSTORM ACTIVITY HERE LATER THIS EVENING AS THE
FRONT MOVES INTO CENTRAL AND EASTERN NORTH DAKOTA. THIS IS COVERED
IN THE CURRENT FORECAST WITH A MENTION OF SHOWERS ACROSS THE FAR
NORTH CENTRAL...AND INTO THE TURTLE MOUNTAINS AREA THIS EVENING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 223 PM CDT SAT AUG 1 2015
SEVERE CONVECTIVE POTENTIAL ACROSS THE JAMES RIVER VALLEY THIS
AFTERNOON HIGHLIGHTS THE SHORT TERM FORECAST.
VISIBLE SATELLITE IMAGERY THROUGH 1920 UTC CONTINUES TO DEPICT A
DEVELOPING CUMULUS FIELD BETWEEN JAMESTOWN...STEELE AND EDGELEY.
THE 13-18 UTC HRRR ITERATIONS HAVE ALL DEPICTED CONVECTIVE
INITIATION FOR THIS AREA BY 21 UTC IN AN ENVIRONMENT CHARACTERIZED
BY ML CAPE AROUND 2000-3000 J/KG AND DEEP LAYER SHEAR OF 30-40
KTS. WITH A SHORTWAVE EVIDENT JUST UPSTREAM ON WATER
VAPOR...CONVECTIVE POTENTIAL IS INCREASING ALONG WITH THE THREAT
FOR LARGE HAIL AND DAMAGING WINDS IN AN ENVIRONMENT SUPPORTIVE OF
SUPERCELLS...AND HAVE THUS ADDED SEVERE WORDING TO THE JAMES RIVER
VALLEY FOR THIS AFTERNOON. EXPECT THE THREAT TO QUICKLY EXIT INTO
THE GRAND FORKS CWA BY 00 UTC.
LATER THIS EVENING A COLD FRONT WILL PROPAGATE FROM NORTHWEST TO
SOUTHEAST ACROSS NORTH DAKOTA...YIELDING A COOLER BUT STILL
SEASONABLE SUNDAY FOR EARLY AUGUST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 240 PM CDT SAT AUG 1 2015
NORTHWEST FLOW ALOFT THROUGH MONDAY NIGHT. DRY CONDITIONS
EXPECTED WITH SURFACE HIGH PRESSURE FIRMLY IN PLACE ACROSS THE
DAKOTAS. DEEP UPPER LOW MOVING SOUTH INTO THE GREAT LAKES REGION
SUNDAY WILL PUSH A BACK DOOR COLD FRONT INTO THE NORTHERN PLAINS
AND KEEP TEMPERATURES RELATIVELY COOL IN THE 70S TO LOW 80S MONDAY
AND TUESDAY.
A MORE ACTIVE PATTERN MATERIALIZES MID TO LATE NEXT WEEK WHEN OUR
FLOW TRANSITIONS TO MORE ZONAL ALLOWING SEVERAL EMBEDDED WAVES TO
MOVE THROUGH THE REGION. BEST THUNDERSTORM CHANCES WILL BE
CONFINED TO THE SOUTH AND WEST INITIALLY...UNTIL LATER IN THE
WEEK WHEN A CLOSED MID LEVEL CROSSES THE ALBERTA ROCKIES AND MOVES
INTO NORTH DAKOTA FRIDAY. TEMPERATURES DO NOT RECOVER MUCH FROM
EARLY IN THE WEEK...AND LOOK TO REMAIN BELOW AVERAGE FOR EARLY
AUGUST WED-FRI (70S TO LOW 80S).
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1221 AM CDT SUN AUG 2 2015
VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD. AT 05Z A COLD
FRONT EXTENDED FROM BETWEEN KDIK/KISN TO BETWEEN KMOT/KN60 TO NEAR
GRAND FORKS. THIS FRONT WILL CONTINUE MOVING SOUTH EARLY THIS
MORNING...REACHING THE SOUTH DAKOTA BORDER BY/BEFORE SUNRISE.
NORTHERLY WINDS 10-15 KNOTS ALONG/BEHIND THE FRONT SHOULD LOWER TO
BELOW 10 KNOTS WITHIN AN HOUR OR TWO OF FRONTAL PASSAGE.
THUNDERSTORMS ALONG THE FRONT EXTENDED FROM LAKE SUPERIOR ACROSS
NORTHERN MINNESOTA AS FAR WEST AS BOTTINEAU. EXPECT THESE CONVECTIVE
CELLS TO REMAIN EAST OF MINOT. WILL NOT MENTION IN KJMS JUST YET AS
EXPECT CONVECTION TO BE EAST OF KJMS AS THE FRONT MOVES SOUTH.
AFTER 15Z/16Z NORTH WINDS SHOULD INCREASE AS SURFACE WINDS LINK TO
THE MIXING WINDS ALOFT.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JV
SHORT TERM...AYD
LONG TERM...NH
AVIATION...JV
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1140 PM CDT SAT AUG 1 2015
.UPDATE...
ISSUED AT 1133 PM CDT SAT AUG 1 2015
QUICK UPDATE... THUNDERSTORM CELLS DROPPING FROM MANITOBA INTO
FAR NORTHEAST ND AND FAR NORTHWEST MN AT THIS TIME... WITH LARGE
HAIL INDICATED IN CELLS FROM HUMBOLDT...ACROSS CARIBOU INTO THE
LAKE OF THE WOODS AREA. EXPECT THESE STORMS TO PERSIST A BIT INTO
THE OVERNIGHT AS THEY PUSH FURTHER EAST-SOUTHEAST. SOME STRONG
TSTM OUTFLOW IS ALSO POSSIBLE WITH THESE STORMS... AS 0-6KM SHEAR
APPROACHES 50KTS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
TWO SEPARATE SHORTWAVES WILL AFFECT THE REGION THIS
EVENING/OVERNIGHT.
THE FIRST WAVE WILL BRING A SEVERE THREAT TO A PORTION OF SE ND
AND WC MN. CURRENT SFC ANALYSIS INDICATES A WEAK SFC LOW ACROSS
SOUTH-CENTRAL NORTH DAKOTA...WITH A WARM FRONTAL FEATURE
EXTENDING TO THE SOUTHEAST. DEWPOINT VALUES ALONG THESE FEATURES
HAVE POOLED INTO THE MID-UPPER 60S...LEADING TO MLCAPE 3000-3500
J/KG. AS THIS SYSTEM EVOLVES AND PROPAGATES TOWARD THE
FA...ANTICIPATE THUNDERSTORM DEVELOPMENT ACROSS THE FAR SOUTHERN
FA. 0-6KM BULK SHEAR 35-40 KNTS COMBINED WITH THE STRONG
INSTABILITY WILL LEAD TO SEVERE STORMS...ALTHOUGH COVERAGE SHOULD
REMAIN ISOLATED GIVEN CONVECTIVE TEMPS NEAR 90F (SOME CAPPING
ISSUES). THIS ACTIVITY WILL MOVE OUT OF THE REGION BY EARLY
EVENING. DID ADD T+ (SEVERE STORMS POSSIBLE) ACROSS FAR SE ND
WHERE CONFIDENCE IS HIGHER IN THUNDER DEVELOPMENT (LOW LEVEL
CONVERGENCE WILL BE MAXIMIZED...AND THE HRRR HAS CONSISTENTLY
INDICATED DEVELOPMENT FROM RUN TO RUN).
NEXT UP WILL BE THE NORTHERN FA THIS EVENING INTO THE OVERNIGHT
HOURS...AS A STRONGER UPPER WAVE BRINGS A COLD FRONT THROUGH THE
REGION. THIS ACTIVITY WILL ENCOUNTER WEAK INSTABILITY (MUCAPE
500-1000 J/KG) BUT VERY STRONG DEEP LAYER SHEAR (60+
KNOTS)...ALONG WITH MID-LEVEL WINDS IN EXCESS OF 50 KNTS. THE 18Z
HRRR IS INDICATING A SMALL BOW ECHO WITH SFC WIND GUSTS 50-55
KNOTS 02Z-05Z. OF COURSE THAT IS JUST ONE POSSIBLE SOLUTION...BUT
IT DOES SPEAK TO THE POTENTIAL OF WHAT COULD OCCUR ACROSS THE
NORTHERN FA THIS EVENING AND OVERNIGHT. THIS FORCING MAY ALSO
INTERACT WITH INCREASING INSTABILITY FROM THE SOUTH AFTER
MIDNIGHT...WHICH MAY BE ENOUGH FOR A FEW STRONGER STORMS INTO THE
OVERNIGHT HOURS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 325 PM CDT SAT AUG 1 2015
THIS PERIOD STARTS OFF WITH A BROAD UPPER LEVEL LOW OVER ONTARIO
AND COOL HIGH PRESSURE IN PLACE AT THE SURFACE OVER SASKATCHEWAN
AND THE DAKOTAS. THE WEATHER WILL BE DRY AND SLIGHTLY COOLER THAN
AVERAGE FOR THE START OF THE WEEK. HOWEVER...A WEAK UPPER LEVEL
WAVE WILL MOVE EAST IN THE WEAK UPPER FLOW...UNDERCUTTING A
WESTERN U.S. RIDGE BY MID WEEK. THE MODELS HAVE HAD A HARD TIME
WITH THIS SYSTEM. PREVIOUS RUNS HAD MORE INSTABILITY AND MUCH MORE
OF A PRECIPITATION SIGNAL AREA-WIDE. THE LATEST GFS HAS BEST
LIFT/INSTABILITY IN THE FAR SOUTH ON WEDNESDAY NIGHT.
SO...CONFIDENCE IS DECREASING IN WEDNESDAYS SYSTEM. ANOTHER WEAK
WAVE WILL AFFECT PRIMARILY THE SOUTH ON THURSDAY...BUT
AGAIN...THIS ONE HAS TRENDED SOUTHWARD. HOWEVER...FRIDAYS SYSTEM
LOOKS TO BE THE WAVE THAT HAS THE MOST AGREEMENT REGARDING TRACK
AND COULD BRING WIDESPREAD PRECIP TO THE AREA. WITH PLENTY OF
UNCERTAINTY ON THESE WAVES...TOO EARLY TO TALK ABOUT SEVERE
POTENTIAL. PRECIPITATION CHANCES EXIST INTO SATURDAY AS WELL AND
WILL DEPEND ON SPEED OF UPPER LOW. TEMPERATURES LOOK TO BE COOL
FOR MUCH OF THIS PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 1135 PM CDT SAT AUG 1 2015
GENERALLY FAIR SKIES THROUGH THE EVENING AND OVERNIGHT ACROSS
THE SOUTHERN FA... WITH WIND SHIFT TURNING FROM THE NORTHWEST
THROUGH THE MORNING HOURS ALONG WITH SOME MID LEVEL CLOUDS.
ACROSS THE NORTHERN FA... A WEAK COLD FRONT DROPPING SOUTHWARD
ACROSS THE CANAM BORDER WILL DEVELOP SCATTERED THUNDERSTORMS AND
AN ISOLATED MVFR CIGS AND VSBYS WITH OCCASIONAL LARGE HAIL IN
STRONG TO SEVERE STORMS... ALG AND NORTH OF A CANDO TO GRAND
FORKS AND BEMIDJI LINE. SCATTERED SHOWERS SHOULD PERSIST INTO THE
MORNING HOURS ACROSS NORTHERN MN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
UPDATE...GUST
SHORT TERM...TG
LONG TERM...KNUTSVIG
AVIATION...GUST
AREA FORECAST DISCUSSION...UPDATED
NWS BROWNSVILLE TX
1241 AM CDT SUN AUG 2 2015
.DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
&&
.AVIATION...SATELLITE IMAGES AND SURFACE OBSERVATIONS INDICATE A
FEW HIGH CLOUDS ACROSS EXTREME SOUTHEAST PORTIONS OF THE CWA LATE
TONIGHT. EXPECT VFR CONDITIONS TO PREVAIL THE REST OF TONIGHT
THROUGH EARLY SUNDAY MORNING. CONVECTION IS EXPECTED TO DEVELOP
ACROSS THE COASTAL SECTIONS SUNDAY AND MOVE INLAND AS A WEAK 500MB
INVERTED TROUGH MOVES ACROSS NORTHEAST MEXICO SUN AFTERNOON.
EXPECT SHOWERS IN THE VICINITY OF LOCAL AERODROMES THROUGH 18Z
SUNDAY AND THUNDERSTORMS IN THE VICINITY OF LOCAL AERODROMES 18Z
THROUGH 24Z SUNDAY AS A RESULT.
&&
.PREV DISCUSSION... /ISSUED 700 PM CDT SAT AUG 1 2015/
DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW.
AVIATION...DISSIPATING SHOWERS APPROACHING SOUTH PADRE ISLAND
HAVE A LOW PROBABILITY OF IMPACTING KBRO THROUGH 9 PM. NO THUNDER
IS ASSOCIATED WITH THIS SMALL AREA OF RAIN AS IT DRIFTS SOUTHWEST
AT AROUND 15 MPH. CEILINGS ASSOCIATED WITH THIS AREA OF RAIN AND
OTHER CLOUDS THROUGH MUCH OF DEEP SOUTH TEXAS ARE IN THE VFR RANGE
WITH NO MVFR OR IFR EXPECTED IN THE NEXT 24 HOURS. PROBABILITIES
FROM HIGH RESOLUTION MODELS CONTINUES TO INDICATE LOW
PROBABILITIES OF ANY AVIATION IMPACTS FROM LOW CLOUDS OR LOW
VISIBILITIES. WINDS WILL CONTINUE TO BE LIGHT AND VARIABLE TONIGHT
BECOMING SOUTHEAST LIGHT TO MODERATE SUNDAY WITH GUSTS BETWEEN 15
AND 20 KNOTS IN THE LATE MORNING AND AFTERNOON.
PREV DISCUSSION... /ISSUED 304 PM CDT SAT AUG 1 2015/
SHORT TERM /NOW THROUGH SUNDAY NIGHT/...SATELLITE IMAGES THIS
AFTERNOON INDICATE MOSTLY MID TO HIGH CLOUDS NEAR THE COAST WITH A
SCATTERED CU FIELD ACROSS THE WESTERN PORTIONS OF THE DEEP SOUTH
TEXAS. THE LATEST BRO RADAR CONTINUES TO SHOW SCATTERED SHOWERS
AND ISOLATED THUNDERSTORMS OVER THE GULF OF MEXICO WATERS...20 TO
60 NAUTICAL MILES EAST OF PADRE ISLAND. THE WEAK 500MB
LOW/INVERTED TROUGH ACROSS THE WESTERN GULF OF MEXICO THIS
AFTERNOON WILL CONTINUE TO PROVIDE LOW TO MID LEVEL MOISTURE OVER
THE WESTERN GULF OF MEXICO AND ALONG THE LOWER TEXAS COAST. THE
12Z BRO SOUNDING SHOWS PRECIPITABLE WATERS OF 1.97 INCHES. THIS
WILL SUPPORT A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS
THE COASTAL SECTIONS OF DEEP SOUTH TEXAS FOR THE REST OF THIS
AFTERNOON WITH DRIER AIR FARTHER INLAND. THE LATEST HRRR KEEPS
MOST...IF NOT ALL...OF THE CONVECTION OFFSHORE AND SOUTH OF THE
RIO GRANDE RIVER NOW THROUGH THIS EVENING. CONVECTION IS EXPECTED
TO DECREASE IN COVERAGE THIS EVENING BEFORE REDEVELOPING OVER THE
GULF WATERS AFTER MIDNIGHT. THE WEAK MID TO UPPER LEVEL FEATURE IS
EXPECTED TO MOVE WESTWARD ACROSS NORTHEAST MEXICO TONIGHT INTO
SUNDAY. LINGERING MOISTURE COMBINED WITH DAYTIME HEATING WILL
PROVIDE A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE
LOWER PORTIONS OF THE RIO GRANDE VALLEY ON SUNDAY.
LONG TERM /MONDAY THROUGH SATURDAY/...THE MAIN ISSUE IN THE
LONGER RANGE PERIOD WILL BE THE HEAT POTENTIAL ACROSS THE RGV. THE
GFS AND ECMWF BOTH RESTRENGTHEN THE 500 MB RIDGING IN PLACE OVER
THE SOUTH CENTRAL PLAINS STATES NEXT WEEK. THIS WILL RESULT IN A
DRIER AND MORE STABLE AIRMASS OVER DEEP SOUTH TX ONCE AGAIN
YIELDING ABOVE NORMAL TEMPS THROUGH DAY 7. THE DEEPER LAYER
MOISTURE VALUES REMAIN PRETTY LIMITED ACROSS THE AREA THROUGH THE
EXTENDED RANGE PERIOD. ONLY A VERY SHALLOW MOISTURE LAYER MAY
PERSIST ON THROUGH DAY 7 WHICH WILL ALLOW FOR SOME LOW LEVEL CLD
COVER TO PERSIST ON THROUGH THE PERIOD. OTHERWISE EXPECT NEAR
ZERO RAIN CHANCES TO PREVAIL.
THE GFS MEX AND ECMWF MODEL HIGH/LOW TEMPS THROUGH THE PERIOD ARE
IN PRETTY DECENT AGREEMENT. SO WILL GO WITH A GENERAL 50/50 BLEND
OF THE TWO MODEL SETS FOR TEMPS. THE GFS MEX POPS STILL TRY TO
TREND TOWARDS SOME SLGT CHC POPS LATE IN THE PERIOD. I BELIEVE
THAT THIS IS MODEL TREND IS BEING SKEWED HIGH DUE TO CLIMO
INFLUENCES. SO WILL GO CLOSER TO THE ECMWF POPS IN THE LONG TERM.
MARINE...NOW THROUGH SUNDAY NIGHT...BUOY020 IS CURRENTLY REPORTING
SEAS OF 1 FOOT WITH NORTH WINDS NEAR 4 KNOTS. LIGHT AND VARIABLE
WINDS WILL PREVAIL ACROSS THE LOWER TEXAS COASTAL WATERS NOW THROUGH
SUNDAY NIGHT DUE TO A WEAK PRESSURE GRADIENT ACROSS THE WESTERN
GULF. WINDS AND SEAS WILL BE HIGHER IN AND NEAR THUNDERSTORMS
ASSOCIATED WITH THE WEAK MID TO UPPER LEVEL DISTURBANCE OVER THE
WESTERN GULF.
MONDAY THROUGH THURSDAY...THE PGF WILL START OF NEXT WEEK FAIRLY
WEAK ALLOWING FOR FAIRLY LOW WINDS AND SEAS TO PREVAIL. THE PGF
WILL THEN START TO STRENGTHEN SOMEWHAT STARTING LATE TUES/WED AS A
SURFACE LOW DEVELOPS OVER THE SOUTHERN PLAINS STATES. THIS MAY
PUSH THE WINDS AND SEAS UP LATE IN THE MARINE FORECAST PERIOD TO
POSSIBLY PRODUCE SOME SCEC CONDITIONS WED/THURS.
&&
.BRO WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT:
HTTP://WEATHER.GOV/RGV
61/64
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
853 AM MST SUN AUG 2 2015
.SYNOPSIS...
CONSIDERABLE DRYING WILL OCCUR TODAY AND INTO THE MIDDLE OF NEXT
WEEK WITH STORM CHANCES CONFINED TO THE HIGHER TERRAIN EAST OF
PHOENIX. TEMPERATURES WILL GRADUALLY WARM AND WILL HOVER NEAR NORMAL
OR SLIGHTLY ABOVE THROUGH NEXT WEEK.
&&
.DISCUSSION...
WHAT A STARK CONTRAST COMPARED TO THE LAST COUPLE OF DAYS. EVEN
THOUGH YESTERDAY ENDED BEING SOMEWHAT QUIET OVER MOST OF THE
AREA...TODAY WILL BE EVEN MORE QUIET. LITTLE MOISTURE IS LEFT FROM
PHOENIX WESTWARD AND WATER VAPOR IMAGERY CONTINUES TO SHOW EVEN DRIER
AIR WORKING IN FROM THE SOUTH. SOME LINGERING LOW LEVEL MOISTURE
SHOULD ALLOW FOR SOME SPORADIC AFTERNOON CU ACROSS THE DESERTS...BUT
DRIER AIR MIXING DOWN WILL QUICKLY DROP SURFACE DEW POINTS FROM THE
CURRENT MID 50S TO LOWER 60S DOWN CLOSER TO 50 DEGREES BY LATE
AFTERNOON. SLIGHT CHANCES OF SHOWERS AND MAYBE A FEW THUNDERSTORMS
WILL BE POSSIBLE OVER HIGHER TERRAIN AREAS EAST OF PHOENIX...BUT AM
NOT ANTICIPATING MUCH ACTIVITY TODAY. TEMPERATURES WILL AGAIN TOP OUT
NEAR 110 DEGREES OR SLIGHTLY WARMER OVER THE DESERTS OF SOUTHEAST
CALIFORNIA AND SOUTHWEST ARIZONA...WHILE HIGHS SHOULD PEAK OUT IN A
104-108 RANGE OVER THE SOUTH-CENTRAL ARIZONA DESERTS. THE CURRENT
FORECAST LOOKS TO BE ON TRACK AND NO SIGNIFICANT CHANGES ARE NEEDED.
&&
.PREVIOUS DISCUSSION...
PRETTY QUIET RADAR EARLY THIS MORNING SAVE FOR A SWATH OF SHOWERS
AND ISOLATED THUNDERSTORMS MOVING INTO NAVAJO AND APACHE COUNTIES.
FAIRLY WEEK SOUTH-SOUTHWEST STEERING FLOW THROUGH A MIXED 850-300MB
LAYER OF 10-15 KTS HAS ALLOWED FOR SUFFICIENT RAINFALL AMOUNTS TO
ACCUMULATE ACROSS THE HIGHER ELEVATIONS OF GILA COUNTY THIS EVENING.
MOST OF THE FOCUS OF MONSOON ACTIVITY WAS ACROSS EASTERN PIMA...GILA
AND GRAHAM COUNTIES SATURDAY EVENING. PER CURRENT SATELLITE IMAGERY A
TONGUE OF DRY AIR IS INFILTRATING SOUTH-CENTRAL ARIZONA MOVING THE
DRY AIRMASS IN FROM THE WEST AND KICKING THE MOISTURE OUT THE DOOR TO
THE EAST. AN UPPER LEVEL SHORTWAVE TROUGH IS THE CULPRIT PUSHING IN
FROM THE WEST BRINGING SOUTHERLY FLOW INTO THE DESERT SOUTHWEST ALONG
WITH DRIER AIR /06Z SUNDAY MIXING RATIOS NEARLY 10 G/KG LESS THAN 24
HOURS AGO/. A BROAD REGION OF DIFFLUENCE STILL RESIDES ACROSS WESTERN
ARIZONA THROUGH EAST CENTRAL NEW MEXICO ALONG THE MOGOLLON RIM...AND
AS EXPECTED THIS WOULD BE THE REGION OF FAVORABLE STORM ACTIVITY
TODAY DURING THIS TRANSITION PERIOD. CURRENT MESOSCALE HIGH RES MODEL
THAT IS IN GOOD AGREEMENT APPEARS TO BE THE HRRR FOR TODAY`S
ACTIVITY.
PER LATEST GFS AND ECMWF...AMONG THEIR ENSEMBLE COUNTERPARTS ARE SLOW
TO MOVE A CUT OFF LOW FORMING IN THE EASTERN PACIFIC TO THE EAST OVER
THE NEXT 5-6 DAYS. THIS WILL ALLOW THE RIDGE OF HIGH PRESSURE TO
FLOAT TO THE WEST AND FLATTEN OUT...WITH A WEAK SOUTHWESTERLY
STEERING FLOW SETTLING IN THROUGH MOST OF THE UPCOMING WEEK. AN
OPTIMUM TIME FOR TEMPERATURES TO GRADUALLY RISE EVEN IF SLIGHTLY
ABOVE SEASONAL AVERAGE...THOUGH AT THIS TIME NONE OF THE GUIDANCE
BRINGS TEMPERATURES TO THE 110 DEGREE MARK FOR PHOENIX BUT THERE ARE
A FEW DAYS WITH 110 OR GREATER OUT ALONG THE LOWER COLORADO
RIVER...GENERALLY A WARMER LOCALE. ALL THIS BEING SAID...STORM
CHANCES OVER THE NEXT 5-6 DAYS ARE SUBSTANTIALLY LESS THAN THE
PREVIOUS DAYS ACROSS THE LOWER DESERTS. A SLIGHT CHANCE WILL BE KEPT
FOR HIGHER ELEVATIONS NORTH AND EAST OF PHOENIX DUE TO THE NATURE OF
MOUNTAIN ACTIVITY. THE NEXT FLOW REVERSAL APPEARS TO SHAPE UP BY LATE
WEEK INTO NEXT WEEKEND AS MOISTURE MAKES A RETURN APPEARANCE AND WIND
FLOW RETURNS TO A SOUTH-SOUTHEASTERLY DIRECTION.
&&
.AVIATION...
SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA...AND KSDL...
SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND
KBLH...
DRIER AND MORE STABLE AIR WILL TRANSITION INTO THE AREA FROM THE
WEST-SOUTHWEST...SHUNTING THE BEST CHANCES FOR ANY STORMS TODAY INTO
THE MOUNTAINS NORTH-EAST-SOUTHEAST OF THE PHX AREA. SKY COVERAGE TO
RANGE FROM SKC TO SCT WITH ANY DAYTIME CU GNLY AOA 10KFT. WINDS WILL
FOLLOW TYPICAL SUMMERTIME PATTERNS...WITH SLIGHTLY ENHANCED WESTERLY
AFTN AND EVENING FLOW FOR KIPL AND THE PHX AREA TERMINALS.
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
TUESDAY THROUGH SATURDAY...
DRIER AND STABLE WESTERLY FLOW ALOFT WILL PRODUCE PARTLY CLOUDY
SKIES TUESDAY AND WEDNESDAY...WITH LOWER MINIMUM RELATIVE HUMIDITY
GENERALLY IN THE 10 TO 15 PERCENT RANGE. MOISTURE WILL GRADUALLY
INCREASE OVER SOUTHWEST AND SOUTH CENTRAL ARIZONA THURSDAY THROUGH
SATURDAY...INTO THE 15 TO 25 PERCENT RANGE...WITH A SLIGHT CHANCE OF
AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS IN SOUTHERN GILA
COUNTY. AFTERNOON SOUTHWEST WINDS 10 TO 15 MPH. FAIR RECOVERY AT
NIGHT. MOISTURE WILL BEGIN TO THIN TOWARDS THE END OF THE
WEEK...WITH DAILY STORM CHANCES PERSISTING FOR THE HIGHER TERRAIN
AND DAYTIME HUMIDITIES STILL RANGING FROM 10 TO 20 PERCENT IN THE
LOWER DESERTS AND 30 TO 35 PERCENT FOR THE HIGHER TERRAIN.
&&
.SPOTTER INFORMATION STATEMENT...
SPOTTERS ARE ENCOURAGED TO REPORT CONDITIONS ACCORDING TO STANDARD
OPERATING PROCEDURES.
&&
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE.
CA...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX
DISCUSSION...KUHLMAN
PREVIOUS DISCUSSION...DEWEY
AVIATION...NOLTE
FIRE WEATHER...NOLTE/VASQUEZ
AREA FORECAST DISCUSSION
NWS RENO NV
303 AM PDT SUN AUG 2 2015
.SYNOPSIS...
PLENTY OF MOISTURE WILL BRING ANOTHER ROUND OF SHOWERS AND
THUNDERSTORMS TODAY TO NORTHEAST CALIFORNIA AND WESTERN NEVADA,
WITH LIGHTNING AND LOCALLY HEAVY RAINFALL THE MAIN THREATS FROM
THUNDERSTORMS. THUNDERSTORM COVERAGE IS EXPECTED TO WANE MONDAY
THROUGH WEDNESDAY AS DRIER AIR WORKS INTO THE REGION. AFTERNOON
TEMPERATURES WILL REMAIN AROUND AVERAGE THIS WEEK.
&&
.SHORT TERM...
MAIN CHANGES TO THE SHORT TERM FORECAST TO CUT BACK THUNDERSTORMS
TO MORE DIURNALLY-DRIVEN (AFTERNOON AND EVENING) TIMING FOR MONDAY
AND TUESDAY.
THE COMPLEX OF SHOWERS AND THUNDERSTORMS WHICH MOVED THROUGH
WESTERN NEVADA LAST EVENING HAS PUSHED OFF TO WEST OF THE SIERRA
CREST THIS MORNING, WITH JUST A FEW SHOWERS LEFT OVER NORTH OF
HIGHWAY 70 IN NORTHEAST CALIFORNIA. LOOKING DOWN INTO SOUTHERN
AND CENTRAL NEVADA, ANOTHER UPPER DISTURBANCE IS WORKING NORTH
PER INFRARED SATELLITE INDICATIONS OF COOLING CLOUD TOPS OVER
ESMERALDA AND NYE COUNTIES. THE IMPULSE IS PROGGED BY THE 08Z HRRR
TO FIRE UP SHOWERS SOUTH OF HIGHWAY 50 IN THE NEXT FEW HOURS,
WHICH MAKES SENSE GIVEN THE APPROACHING COOLING CLOUD TOPS AND THE
RATHER MOIST ATMOSPHERE. ELSEWHERE SOUTH AND WEST OF AN ALTURAS TO
RENO TO FALLON LINE, A FEW STRAY SHOWERS OR EVEN A VERY ISOLATED
LIGHTNING STRIKE CANNOT BE RULED OUT THIS MORNING.
THIS AFTERNOON, THE HRRR AND NAM HAVE TRENDED TOWARDS FOCUSING THE
BEST SHOT AT CONVECTION NORTH OF HIGHWAY 50 AHEAD THE INCOMING
UPPER DISTURBANCE. THOSE MODELS HAVE ALSO REDUCED THEIR AFTERNOON
PRECIPITATION FORECAST FOR MONO AND MINERAL COUNTIES AS THEY
FOCUS THE FORCING FARTHER NORTH. HOWEVER, PLENTY OF MOISTURE
REMAINS FOR AREAS SOUTH OF HIGHWAY 50 AND THE NAM SHOWS SOME
WESTERLY WINDS IN THE AFTERNOON WHICH COULD PROVIDE FOCUS FOR
SCATTERED DEEP CONVECTION. THEREFORE, I HAVE HELD OFF ON REDUCING
POP WHOLESALE FOR MONO/MINERAL COUNTIES FOR THIS AFTERNOON AND
EVENING.
AS FAR AS THE NATURE OF THUNDERSTORMS THIS AFTERNOON, THE RELATIVELY
HIGH MOISTURE BROUGHT INTO THE REGION SINCE YESTERDAY (PWAT NEAR
1" IN RENO CURRENTLY) SHOULD ALLOW FOR MODERATE TO HEAVY RAIN
UNDER STORM CORES DESPITE SOME MODEST STORM MOTION OF UP TO 10-15
KTS. IN FACT, IF STORMS GET HUNG UP ON TERRAIN OR TRAIN OVER THE
SAME AREA LOCALIZED FLOODING WILL BE POSSIBLE GIVEN THE HEAVY RAIN
POTENTIAL WITH THE HIGH PWATS.
LATE TONIGHT, AS THE UPPER DISTURBANCE CONTINUES TO TREK SLOWLY
THROUGH NORTHERN NEVADA, SHOWERS AND A FEW THUNDERSTORMS WILL BE
POSSIBLE IN THE BASIN AND RANGE AND OVER EXTREME NORTHEAST
CALIFORNIA.
MONDAY AND TUESDAY, THUNDERSTORM COVERAGE SHOULD WANE AS PWATS
FALL OFF SOME WITH DRIER WESTERLY FLOW IMPINGING ON THE REGION.
ALSO, WITH WEAKER UPPER FORCING AS COMPARED TO THE PAST COUPLE
DAYS, STORMS WILL NEED TO RELY ON DAYTIME HEATING TO DEVELOP.
THEREFORE, I HAVE CUT BACK THE THUNDERSTORM TIMING TO MORE
DIURNALLY-DEPENDENT TIMES. STORM FLOW WILL INCREASE FOR MONDAY
AND TUESDAY, WHICH MAY BRING HYBRID WET/DRY STORMS BACK INTO PLAY
VERSUS THE WETTER STORMS EXPECTED FOR TODAY. SEE THE FIRE WEATHER
SECTION FOR MORE ON THE CONCERNS WITH CONVECTION ON MONDAY AND
TUESDAY. SNYDER
.LONG TERM...WEDNESDAY THROUGH SATURDAY...
FEW CHANGES MADE TO THE LONG TERM WITH THE FIRST PART OF THE
UPPER LOW EXITING ON WEDNESDAY WITH THE MAIN LOW NOW FORECAST TO
MOVE THROUGH FRIDAY INTO SATURDAY. HAVE ADDED A SLIGHT CHANCE OF
THUNDERSTORMS NORTH OF SUSANVILLE AND GERLACH WEDNESDAY WITH
RESIDUAL MOISTURE AND INSTABILITY. AREAS FURTHER SOUTH WILL BE TOO
STABLE. A BREAK IS EXPECTED THURSDAY BEFORE THE MAIN LOW MOVES IN
LATE FRIDAY INTO SATURDAY. THIS LOW WILL TRACK FURTHER SOUTH AND
IT WILL BE COOLER ALOFT WITH IT. WHILE MOISTURE WILL NOT BE GREAT,
THE COOLER TEMPS ALOFT WILL BE CONDUCIVE FOR CONVECTION AT LEAST
NORTH OF HIGHWAY 50. ADDED THUNDERSTORMS FRIDAY AND FRIDAY NIGHT
FOR THESE AREAS. STRONG FORCING WILL CONTINUE OVERNIGHT WITH
ANOTHER ROUND OF CONVECTION POSSIBLE. THE STORMS MAY CONTINUE INTO
SATURDAY AS THE UPPER LOW MOVES ACROSS.
TEMPERATURES WILL REMAIN NEAR TO A LITTLE BELOW AVERAGE FOR EARLY
AUGUST. THE WARMEST TEMPERATURES ARE LIKELY THURSDAY BETWEEN SYSTEMS
WITH HIGHS ONLY IN THE 80S FRIDAY AND SATURDAY FOR WESTERN NV AND
70S IN THE SIERRA. A TYPICAL AFTERNOON ZEPHYR IS EXPECTED WEDNESDAY
BEHIND THE FIRST SYSTEM ONLY TO SEE THE FLOW BACK TO THE SOUTH AHEAD
OF THE MAIN UPPER LOW. THE WINDS WILL BE LIGHTER WITH PERHAPS A
LIGHT AFTERNOON ZEPHYR FOR THURSDAY. WALLMANN
&&
.AVIATION...
SCATTERED THUNDERSTORMS HAVE MOVED WEST OF THE SIERRA CREST EARLY
THIS MORNING. ABUNDANT MID AND HIGH CLOUDS ALONG WITH ISOLATED
SHOWERS REMAIN, BUT CONDITIONS WILL STILL BE VFR. A FEW THUNDERSTORMS
ARE POSSIBLE THIS MORNING 13-18Z NEAR KMMH AND KHTH, ABOUT A 10%
CHANCE. FOR THE AFTERNOON, EXPECT STORMS TO FIRE AROUND 19Z AND
LAST THRU 02Z NEAR HIGHWAY 395 AND 05Z FURTHER EAST. CHANCE OF
IMPACT AT KTRK/KTVL/KRNO/KCXP ABOUT 35% WITH SMALL HAIL AND SFC
WND GUSTS TO 40 KTS. LESSER CHANCE FOR KMMH THIS AFTERNOON AT
AROUND 25%.
EXPECT VFR CONDITIONS OVERNIGHT WITH LESS STORMS FOR MONDAY. ONLY A
20% CHANCE OF STORMS AFFECTING TERMINALS AND LESS THAN 10% FOR
KTRK/KTVL. WALLMANN
&&
.FIRE WEATHER...
ISOLATED SHOWERS CONTINUE AFTER THE SCATTERED STORMS FROM EARLIER
THIS MORNING HAVE MOVED WEST OF THE SIERRA CREST. MORE STORMS ARE
EXPECTED TO FIRE THIS AFTERNOON AND WITH MOISTURE UP, STORMS ARE
EXPECTED TO BE WET. SOME AREAS ALREADY RECEIVED UP TO 3/4" OF RAIN
YESTERDAY FROM STORMS AND THE SAME IS POSSIBLE TODAY. EVEN SO, A FEW
SMALL FIRES OUTSIDE STORM CORES ARE POSSIBLE FROM LIGHTNING STRIKES.
A LITTLE DRIER MONDAY AS SOUTHWEST FLOW INCREASES. IT ALSO APPEARS
TO STABILIZE A BIT WITH ONLY ISOLATED THUNDERSTORMS AT BEST EXCEPT
OVER MINERAL COUNTY. STORMS WILL BE MORE HYBRID WET/DRY, BUT WITH
LOWER COVERAGE DO NOT THINK ANY WATCHES/WARNINGS ARE NECESSARY.
TUESDAY MORNING INTO TUESDAY NIGHT A PIECE OF THE UPPER LOW OFF THE
COAST WILL MOVE THROUGH AND THE FORCING WILL BE STRONG MOISTURE
REMAINS WITH PW AROUND 0.6", BUT LAPSE RATES ALOFT ARE ACTUALLY
SOMEWHAT STABLE. THERE ARE DIFFERENCES IN THE MODELS WITH THE EC/GFS
DRIER AND MORE STABLE WHILE THE NAM SHOWS A SLUG OF MOISTURE NEAR
600 MB THAT WOULD BE ENOUGH TO GENERATE CONVECTION AS EARLY AS
TUESDAY MORNING. IF THE NAM IS RIGHT, A DECENT DRY LIGHTNING
OUTBREAK IS POSSIBLE FOR WESTERN NV, WHILE IT WOULD BE ONLY ISOLATED
AT BEST WITH THE EC/GFS. LEANING TOWARD THE EC/GFS FOR NOW, BUT WILL
BE MONITORED.
THE NEXT CONCERN WOULD BE WHEN THE UPPER LOW FINALLY MOVES ONSHORE
LATER THURSDAY NIGHT INTO FRIDAY. IT WILL BE MORE UNSTABLE WITH
COOLER TEMPS ALOFT WITH ONLY MARGINAL MOISTURE. MORE DRY LIGHTNING
IS POSSIBLE WITH THIS LOW AS WELL. WALLMANN
&&
.REV WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
CA...NONE.
&&
$$
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
936 AM MDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 926 AM MDT SUN AUG 2 2015
LIGHT PRECIPITATION COMING TO AN END OVER THE FAR NE CORNER WITH
THE HELP OF HIGH DEWPOINTS AND THE EDGE OF AN UPPER LEVEL JET.
EXPECT DEVELOPMENT TO CONTINUE OVER THE MOUNTAINS WITH INCREASED
MOISTURE AND AN UPPER LEVEL WAVE. INCREASED POPS OVER THE PLAINS
WITH THE CLOUD COVER AND A FRONT NORTH OF NEBRASKA THAT IS STILL
PROGGED TO TRACK INTO NE COLORADO BY THIS EVENING/EARLY MONDAY
MORNING. LATEST RUN OF THE HRRR HAS SOME GUSTY WINDS MOVING SOUTH
OUT OF WY FROM OUTFLOWS PROVIDED BY STORM DEVELOPMENT TO THE
NORTH. MAINTAINED SLIGHT CHANCE INTO THE EVENING. MAIN THREATS
STILL LOOK TO BE MODERATE TO HEAVY RAIN AND GUSTY WINDS WITH THE
STORMS.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 340 AM MDT SUN AUG 2 2015
WATER VAPOR IMAGERY SHOWING ELONGATED UPPER RIDGE FROM THE
PACIFIC NORTHWEST AND EXTENDING SOUTHEAST INTO COLORADO WITH A
WEST TO NORTHWEST FLOW ALOFT OVER NORTHERN COLORADO. OVERALL NOT
MUCH CHANGE IN MOISTURE LEVELS OVER EASTERN COLORADO WITH
INTEGRATED PW VALUES JUST UNDER AN INCH OVER THE FRONT RANGE AND
A BIT HIGHER OVER WESTERN COLORADO. THERE IS QUITE A BIT OF MIDDLE
AND HIGH LEVEL CLOUD COVER NOW OVER THE SOUTHERN 2/3 OF COLORADO.
THERE IS AN UPPER WAVE OVER SOUTHERN NEVADA WHICH WILL SLOWLY
ROTATE INTO WESTERN COLORADO TONIGHT WHICH WILL AID IN ADDITIONAL
MOISTURE AND WEAK QG LIFT.
INITIALLY...SHOWER ACTIVITY WILL BE CONFINED TO THE MOUNTAINS BY
EARLY AFTERNOON BUT SLOWLY SNEAK OUT ONTO THE PLAINS DURING THE
LATE AFTERNOON. A WEAK MID LEVEL CAPPING INVERSION REMAINS WHICH
WILL LIMIT CONVECTION ON THE PLAINS WITH OVERALL SURFACE BASED
CAPE VALUES UNDER 700J/KG. APPEARS A WEAK FRONTAL BOUNDARY WILL
APPROACH THE FAR NE PLAINS TOWARDS EVENING WITH A SLIGHT CHANCE4
OF THUNDERSTORMS SPARKING THERE. TEMPERATURES EXPECTED TO BE VERY
SIMILAR TO SATURDAYS READINGS BUT MAYBE A DEGREE OR TWO DOWN
CLOSER TO THE FRONT RANGE WITH MORE CLOUD COVER. WILL KEEP LOW
POPS IN THE MOUNTAINS THROUGH THE NIGHT AS THE UPPER TROF WILL
APPROACH WITH AIDED MOISTURE AND LIFT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 318 AM MDT SUN AUG 2 2015
MID-LEVEL SHORTWAVE TROUGH IS STILL FORECAST TO SWING NEWRD ACROSS N-
CNTRL/NERN CO MON AFTERNOON/EVENING...THEN SEWRD ACRS ERN WY/WRN
SD/WRN NE ON TUE AS THE UPPER RIDGE BUILDS OVER THE 4-CORNERS RGN.
SHOULD SEE SCATTERED TO NUMEROUS SHWRS/T-STORMS IN THE HIGH COUNTRY
DURING THE DAY MON AND SCATTERED T-STORMS ON THE PLAINS DURING THE
AFTERNOON AND EVENING HOURS. SYSTEM APPEARS MOST ROBUST ON THE NAM
AND ONLY LACK LUSTER ON THE ECMWF. NAM GENERATES SOME RIDICULOUSLY
HIGH CAPES ACRS THE NERN CORNER OF CO IN THE VCNTY OF A STALLED SFC
FRONTAL ZONE STRADDLING THE NERN CORNER OF THE STATE AND A LOW-LEVEL
JET ALIGNED WITH THE STATE`S ERN BORDER MON NIGHT AND TUE. GFS...
ECMWF AND SREF INDICATE FAR LESS INSTABILITY BUT STILL INDICATE
DECENT SHEAR IN THE VCNTY OF THE LOW-LEVEL JET. MEANWHILE THE
CANADIAN MODEL GOES SO FAR AS TO SPIN UP A CLOSED 700-500MB LOW OVER
NERN CO LATE MON AND THEN DEEPENS IT AS IT SLOWLY TRACKS E/SEWRD
ACRS NWRN KS OVERNIGHT. PREFER A BLEND OF THE MODELS...EXCLUDING THE
CANADIAN GEM...CENTERED ON THE GFS SOLUTION. FOR THE PLAINS...PLAN
ON GOING WITH HIGHER POPS UP AGAINST THE NRN FRONT RANGE AND ALONG
THE WY BORDER DURING THE AFTERNOON...AND OUT ACRS THE NERN CORNER OF
THE STATE MON NIGHT. STORMS FORMING IN THE VICINITY OF THE STALLED
FRONTAL BOUNDARY AND LOW-LEVEL JET ARE MORE LIKELY TO PRODUCE HVY
RAINFALL...STG GUSTY WNDS AND HAIL. HIGH TEMPS ON MON EXPECTED TO BE
SEVERAL DEGS LOWER THAN THOSE ON SUNDAY DUE IN LARGE PART TO
CONSIDERABLE MORE CLOUDINESS.
ON TUE...SHOULD SEE PRECIP CHANCES QUICKLY DECREASE FROM WEST-TO-
EAST AS DRIER/COOLER AIR SWEEPS IN ON W/NWLY FLOW BEHIND THE EXITING
SHORTWAVE. HOWEVER COULD SEE A MODEST UPTICK IN SHOWER/T-STORM
ACTIVITY ACRS THE NERN CORNER OF THE CWA TUE AFTERNOON WITH THE
SHORT-WAVE DYNAMICS BRUSHING THE AREA. HIGHS ON TUESDAY SLIGHTLY
WARMER THAN THE DAY BEFORE BUT STILL BELOW THE SEASONAL AVERAGE.
WED THROUGH SAT...A STRONG UPPER RIDGE TAKES HOLD OF THE REGION ON
WED RETURNING TEMPS TO SLIGHTLY ABOVE AVERAGE. MODELS SHOW A WEAK
MID-LEVEL PERTABATION ROUNDING THE TOP OF THIS RIDGE AND POSSIBLY
GENERATING A FEW T-STORMS ACROSS THE FAR NERN CORNER OF THE CWA WED
AFTERNOON AND EVENING. OTHERWISE A DRY DAY WITH MORE SUNSHINE AND
LOWER HUMIDITY. ON THU...MODELS SHOW YET ANOTHER SOMEWHAT STRONGER
MID-LEVEL DISTURBANCE MOVING OUT OF THE NRN ROCKIES AND DOWN ACRS
THE CENTRAL GREAT PLAINS. THE TAIL END OF THE DISTURBANCE APPEARS TO
CLIP THE NERN CORNER OF FCST AREA THU AFTERNOON AND EVENING AND
POTENTIALLY PRODUCING ANOTHER ROUND OF T-STORMS. MORE CLOUDS AND
SLIGHT COOLER ALOFT SHOULD RESULT IN SLIGHTLY COOLER TEMPS ON
THU. ON FRI...RIDGE REGAINS ITS GRIP ON COLORADO RESULTING IN
WARMER TEMPS AND MORE SUNSHINE. HOWEVER WITH THE WARMER TEMPS AND
SUNSHINE COULD SEE WIDELY SCATTERED AFTERNOON T-STORMS FORMING
OVER THE FRONT RANGE AND MOVING OUT OVER THE PLAINS BY THE
EVENING. ON SAT...MODELS SHOW THE UPPER RIDGE MOVING EAST ALLOWING
SWLY FLOW ALOFT TO USHER IN SUBTROPICAL MOISTURE AND SHORTWAVE
TROUGH FROM THE DESERT SOUTHWEST. TOO SOON TO KNOW WITH ANY
CERTAINTY HOW WET AND STORMY SAT MAY TURN OUT. WILL NEED TO KEEP
AN EYE THIS LATE WEEK SYSTEM.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z MONDAY MORNING)
ISSUED AT 926 AM MDT SUN AUG 2 2015
VFR EXPECTED FOR THE NEXT 24 HOURS. ADDED SOME LIGHT SHRA IN A
TEMPO WITH LATEST MODEL GUIDANCE AND A WEAK CAP WITH INCREASED
INSTABILITY. COULD SEE SOME OUTFLOWS FROM THE NORTH THAT WILL HELP
TO BRING IN SOME GUSTY WINDS ALONG WITH A LINE OF RAINSHOWERS
AROUND 23Z. WINDS WILL BE LIGHT THROUGH THE DAY THEN TRANSITION TO
THE NW BEFORE GOING TO DRAINAGE BY THIS EVENING AS STORMS CLEAR
OUT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BOWEN
SHORT TERM...ENTREKIN
LONG TERM...BAKER
AVIATION...BOWEN
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1031 AM EDT SUN AUG 2 2015
.SYNOPSIS...
A WEAK PRESSURE TROUGH WILL REMAIN IN THE FORECAST AREA THROUGH
TUESDAY. DEEPER MOISTURE WILL REMAIN SUPPRESSED EAST AND SOUTH OF
THE AREA. ABOVE NORMAL TEMPERATURES EXPECTED THROUGH MID WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE UPPER-LEVEL PATTERN FEATURES A RIDGE OUT WEST WITH A BROAD
TROUGH FROM THE GREAT LAKES TO THE EAST COAST. WATER VAPOR
SATELLITE IMAGERY SHOWED DRY AIR ALOFT ACROSS THE MIDLANDS AND
CSRA.
WEAKENING FRONTAL BOUNDARY ACROSS THE SOUTHERN MIDLANDS THIS
MORNING SHOULD SHIFT TO THE COAST THIS AFTERNOON. FOG/STRATUS
RAPIDLY MIXING OUT ACROSS THE SOUTHERN MIDLANDS AND CSRA AT 14Z.
SKIES BECOMING MOSTLY SUNNY.
MODELS SOUNDINGS INDICATE A DRY AND CAPPED AIR MASS OVER CENTRAL
SOUTH CAROLINA TODAY. AIR MASS WEAKLY UNSTABLE IN THE EAST AND
SOUTH MIDLANDS/CSRA. POSSIBLE SEA BREEZE/OUTFLOW FROM COASTAL
CONVECTION COULD TRIGGER A FEW ISOLATED THUNDERSTORMS THERE THIS
AFTERNOON. MAX TEMPERATURES MAINLY IN THE MID TO UPPER 90S.
THE NAM AND RAP MODELS SUGGEST FOG/STRATUS DEVELOPING AGAIN LATE
TONIGHT. KEPT LOWS IN THE LOW/MID 70S.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
MODELS SUGGEST WEAK LOW PRESSURE OVER FLORIDA PANHANDLE AREA WILL
MOVE NORTHEAST ALONG THE SOUTH CAROLINA COASTAL FRONT MONDAY AND
MONDAY NIGHT. MOISTURE FLUX CONFINED TO THE COASTAL SOUTH CAROLINA
AS AIR MASS INLAND REMAINS MAINLY DRY. THERE IS SOME UNCERTAINTY
IN THE ENSEMBLE GUIDANCE...HOWEVER THE BULK OF GUIDANCE SUGGESTS
LOW POPS ACROSS CWA. WILL CONTINUE LOW CHANCE POPS MONDAY IN THE
EXTREME EAST MIDLANDS...MAINLY DIURNAL CONVECTION. DRY AIR MASS
EXPECTED TUESDAY WITH WARMING CONDITIONS...POSSIBLY NEAR 100
DEGREES IN A FEW AREAS AS 850MB WARM ADVECTION/DOWN SLOPE FLOW
DEVELOPS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS HAVE BEEN CONSISTENT SHOWING A RIDGE OVER THE CENTRAL US
WITH A BROAD TROUGH ALONG THE EAST COAST. ISOLATED AFTERNOON
CONVECTION AT MOST WEDNESDAY AFTERNOON. MOISTURE RETURNS TO THE
REGION LATER IN THE WEEK. RAISED POPS INTO THE 30-40 PERCENT
THURSDAY THROUGH SATURDAY. HIGH TEMPERATURES IN THE MID 90S
THROUGH MID- WEEK...LOWERING INTO THE LOWER 90S THURSDAY THROUGH
SATURDAY. OVERNIGHT LOWS GENERALLY IN THE LOWER TO MID 70S.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
VFR THROUGH THE EVENING HOURS AT CAE/CUB. MORNING FOG/STRATUS
AFFECTING AGS/DNL/OGB LIFTING. ALL TAF SITES SHOULD BE VFR BY
16Z.
A WEAK SURFACE BOUNDARY ACROSS THE AREA WITH DRY AIR NORTH AND
PLENTY OF LOW LEVEL MOISTURE TO THE SOUTH. A DRY AND CAPPED
ATMOSPHERE WILL REMAIN IN PLACE OVER MOST OF THE NORTHERN AND
CENTRAL MIDLANDS...AND IS EXPECTED TO PRECLUDE CONVECTION. AN
ISOLATED DIURNAL SHOWER OR THUNDERSTORM MAY OCCUR MAINLY SOUTH
POSSIBLY NEAR DNL/AGS/OGB...BUT CHANCES TOO LOW TO INCLUDE MENTION
IN THE TAFS AT THIS TIME.
FOG/STRATUS...POSSIBLE LATE TONIGHT/EARLY MONDAY MORNING.
EXTENDED AVIATION OUTLOOK...
RESTRICTIONS POSSIBLE IN LATE NIGHT/EARLY MORNING FOG.
OTHERWISE...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
559 AM CDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 514 AM CDT SUN AUG 2 2015
THE VORT MAX MOVING INTO OUR AREA ALONG WITH THE H85 THETAE
PUSH....SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS WESTERN
AND SOUTHERN IA EARLY THIS AM. HRRR SUGGESTS THAT THESE STORMS
CONTINUE TO FIRE CLOSER TO US AND THEN MOVE THROUGH OUR AREA. AS A
RESULT OF THE TRENDS AND GUIDANCE...DECIDED TO INCREASE POPS AFTER
12Z ACROSS MY WESTERN ZONES. MAY NEED TO INCREASE TO LIKELYS IF
CURRENT HRRR IS CORRECT.
&&
.SYNOPSIS...
ISSUED AT 329 AM CDT SUN AUG 2 2015
AN AGITATED ACCAS DECK ASSOCIATED WITH A QUICK MOVING VORT MAX IN
THE STEERING FLOW WAS LOCATED FROM ESCANABA MI TO HASTINGS NE.
EXTREMELY ISOLATED CONVECTION HAS FORMED IN THIS BAND AS IT
MARCHES TO THE SE AT AROUND 20 KTS. AT THE SFC...DEWPOINTS ARE
POOLING ACROSS THE AREA AND RELATIVELY CLEAR SKIES REMAIN ACROSS
THE AREA. WITH THE POOLING MOISTURE....TEMPS HAVE BEEN SLOW TO
DROP ACROSS THE AREA. GUIDANCE SUGGESTS AN H85 THETAE PUSH OF
NEAR 50 DEGREES INTO THE AREA NEAR 12Z. THIS AND THE VORT MAX WILL
DOMINATE OUR WEATHER IN THE NEXT 6 TO 12 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT SUN AUG 2 2015
MAIN FORECAST CONCERN FOR THE SHORT ARE THE CHANCES FOR
THUNDERSTORMS AND RAIN TODAY. THERE ARE TWO CHANCES WITH THE FIRST
ONE EITHER ONGOING AT 12Z OR STARTING SHORTLY THEREAFTER. THE
OTHER IS ASSOCIATED WITH A COLD FRONT THAT WILL MOVE THROUGH THE
AREA TODAY AND INTO TONIGHT. SOME OF THE STORMS LATER THIS
AFTERNOON AND EVENING COULD BE STRONG TO SEVERE.
THIS MORNING THE ACCAS DECK MOVING INTO THE AREA WILL ENCOUNTER AN
H85 THETAE PUSH. THESE TWO ARE FORECAST TO BE COINCIDENT ACROSS
THE CWA NEAR 12Z. THIS COULD LEAD TO THE DEVELOPMENT OF SHOWERS
AND THUNDERSTORMS ACROSS THE AREA. LARGE SCALE MODELS HINT AT THIS
POSSIBLY HAPPENING...HOWEVER THE MESOSCALE NATURE OF THE FORCINGS
ARE DIFFICULT FOR THE MODELS TO HANDLE CORRECTLY. PERUSING THE
CAMS...WHICH DO BETTER WITH MESOSCALE FEATURES...IT IS CLEAR THAT
THESE MODELS DO SUGGEST ADDITIONAL THUNDERSTORM DEVELOPMENT THIS
MORNING WITH THE WAVE. AT THIS TIME...THESE STORMS ARE NOT
EXPECTED TO BE SEVERE. A STRONG STORM WITH SMALL HAIL COULD BE
POSSIBLE. I DO NOT HAVE HIGH CONFIDENCE IN THIS OCCURRING SO
DECIDED TO GO WITH SCHC POPS UNTIL THE ACCAS BECOMES BETTER
AGITATED. ANY STORMS THIS AM COULD LEAVE OFBS THAT MAY
INFLUENCE CONVECTION LATER.
THIS AFTERNOON...GUIDANCE SUGGESTS THAT MIXING WILL RESULT IN HIGH
TEMPS IN THE 90S ACROSS THE AREA. SOUNDINGS INDICATE THE EML HAS
RESULTED IN DRIER AIR ALOFT. AS THIS DRIER AIR IS MIXED DOWN...THE
TEMPS SHOULD INCREASE AND DEWPOINTS SHOULD LOWER. USED MOSGUIDE
FOR THE DEWPOINTS AS THEY SEEMED TO HAVE A BETTER HANDLE ON WHAT
WAS GOING ON NOW AND MIXING THE DEWPOINTS LOWER THIS PM. AS A
RESULT...HEAT INDICES WILL REMAIN BELOW CRITERIA.
LATE THIS AFTERNOON A COLD FRONT WILL MOVE THROUGH THE AREA.
LOOKING AT THE THUNDERSTORM POTENTIAL...THERE WILL BE SUFFICIENT
DEEP LAYER SHEAR FOR ISOLATED CELLS. WITH THE MAIN FORCING TO THE
NORTH...THESE STORMS MAY BE SLOWER TO GROW UPSCALE INTO A MCS.
LAPSE RATES IN THE MID LEVELS SUGGEST THAT HAIL WILL BE THE MAIN
THREAT. WITH THE HIGH TEMPS AND LIKELY HIGHER STORM
BASES...DAMAGING WINDS COULD ALSO BE POSSIBLE. LOW LEVEL SHEAR
AND HODOS ARE INDICATIVE OF THE POSSIBILITY OF TORNADOES AS WELL.
IN FACT THEY ARE VERY FAVORABLE FOR POSSIBLE TORNADOES.
HOWEVER...THE THERMODYNAMIC ENVIRONMENT IS NOT. I THINK THE THREAT
OF TORNADOES IS HIGHER WITH AN MCS INSTEAD OF A SUPERCELL STORM
THAT MAY BE THE FIRST MODE OF DEVELOPMENT. REGARDLESS THERE IS A
THREAT FOR SEVERE WEATHER FROM THESE STORMS.
LOOKING AT THE CAMS...THE NAM 4KM HAS THE BULK OF THE STORMS AND
BOWING STRUCTURES ACROSS WI AND E IL. THIS MODEL POPS SHORT LIVED
ISOLATED CELLS THAT STRUGGLE TO GROW UPSCALE INTO A MCS
STRUCTURES. THE WRFNMM AND ARW ARE EERILY SIMILAR IN WHICH A
FRONTAL MCS COMES THROUGH OUR AREA INSTEAD OF TO THE EAST.
REGARDLESS THESE MODELS PRODUCE STORMS AND THUS GIVE ME HIGHER
CONFIDENCE THAT CONVECTION WILL OCCUR. DID NOT GO HIGHER THAN CHC
AS I DO NOT HAVE AN IDEA OF WHICH OF THE SOLUTIONS WILL OCCUR.
LATER SHIFTS MAY BE ABLE TO INCREASE POPS ACROSS THE AREA AS THE
DAY PROGRESSES AND A CLEARER SOLUTION IS SEEN.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN AUG 2 2015
MONDAY AND MONDAY NIGHT... NORTHWEST FLOW ALOFT WILL DOMINATE EARLY IN THE
WEEK AS ANOMALOUSLY DEEP UPPER LOW (500 MB HEIGHTS OF 550-555 DECAMETERS
EQUATING TO ROUGHLY 2+ STANDARD DEVIATIONS BELOW CLIMO PER NAEFS) REMAINS
PARKED NEAR QUEBEC. THIS FLOW PATTERN COUPLED WITH HIGH PRESSURE RIDGE
BUILDING IN WILL RESULT IN COOLER (NEAR NORMAL) AND DRIER CONDITIONS
TO START THE WEEK. A SURFACE FRONT IS ANTICIPATED TO STALL OUT FROM THE
CENTRAL PLAINS TO THE APPALACHIANS BY MONDAY EVENING. ISENTROPIC LIFT AND
WEAK LOW AMPLITUDE SHORTWAVES WILL PROVIDE FOCUS FOR PRECIPITATION CHANCES
NEAR AND ON COOL SIDE OF BOUNDARY...WITH THE FAR SOUTHERN CWA POTENTIALLY IN
CLOSE PROXIMITY TO SOME OF THIS ACTIVITY.
TUESDAY AND TUESDAY NIGHT... OVERALL PATTERN NOT SHOWING MUCH CHANGE
DURING THIS PERIOD WITH UPPER LOW SLOW MOVING THROUGH ONTARIO... AND
CWA STAYING ON COOL SIDE OF STALLED FRONTAL ZONE FROM THE PLAINS THROUGH THE
MID-MISSISSIPPI VALLEY. THUS... MORE OF THE SAME WITH PLEASANT CONDITIONS
WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPS AND COMFORTABLE HUMIDITY LEVELS...
AND ANY RAIN CHANCES MAINLY TO OUR SOUTH/WEST IN VICINITY OF STALLED FRONT
WITH SOUTHERN CWA STANDING ANY CHANCES FOR RAIN BEING IN CLOSER PROXIMITY TO
BOUNDARY.
WEDNESDAY THROUGH SATURDAY... CONTINUED GRADUAL DRAWN DOWN ON TEMPS TO BELOW
NORMAL EXPECTED INTO LATE WEEK WITH INFLUX OF COOLER AIR (850 MB TEMPS
LOWERING INTO RANGE OF 12-16C) IN WAKE OF DEPARTING ONTARIO UPPER LOW.
IN ADDITION...LIKELIHOOD OF INTERVALS OF CLOUDINESS WITH SERIES OF UPPER LEVEL
DISTURBANCES PROPAGATING THROUGH REGION IN THE SEMI-ZONAL TO NORTHWEST FLOW
TO AID IN KEEPING TEMPS BELOW NORMAL. WITH SURFACE FRONT NEARBY WILL MAINTAIN
RAIN CHANCES THROUGH THURSDAY THEN TRENDS SUPPORT DRYING OUT LATE WEEK INTO THE
WEEKEND WITH ANOTHER BOUT OF GREAT LAKES RIDGING AND INFLUX OF COOLER...DRIER AIR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 553 AM CDT SUN AUG 2 2015
VFR CONDITIONS ARE FORECAST THROUGH THE PERIOD. SHOWERS AND
THUNDERSTORMS ARE POSSIBLE IN TWO ROUNDS TODAY. THE FIRST ROUND
WILL BE THIS MORNING AND MAY AFFECT BRL AND MLI. THIS AFTERNOON A
COLD FRONT MOVES IN FROM THE NORTH. THUNDERSTORMS COULD BE STRONG
TO SEVERE WITH THIS FRONT. AT THIS TIME ONLY USED PROB30 AS NOT
SURE WHETHER OR NOT THIS AM CONVECTION WILL AFFECT TONIGHTS. COULD
SEE MVFR RESTRICTIONS WITH THUNDERSTORMS TONIGHT.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...05
AVIATION...GIBBS
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
516 AM CDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 514 AM CDT SUN AUG 2 2015
THE VORT MAX MOVING INTO OUR AREA ALONG WITH THE H85 THETAE
PUSH....SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ACROSS WESTERN
AND SOUTHERN IA EARLY THIS AM. HRRR SUGGESTS THAT THESE STORMS
CONTINUE TO FIRE CLOSER TO US AND THEN MOVE THROUGH OUR AREA. AS A
RESULT OF THE TRENDS AND GUIDANCE...DECIDED TO INCREASE POPS AFTER
12Z ACROSS MY WESTERN ZONES. MAY NEED TO INCREASE TO LIKELYS IF
CURRENT HRRR IS CORRECT.
&&
.SYNOPSIS...
ISSUED AT 329 AM CDT SUN AUG 2 2015
AN AGITATED ACCAS DECK ASSOCIATED WITH A QUICK MOVING VORT MAX IN
THE STEERING FLOW WAS LOCATED FROM ESCANABA MI TO HASTINGS NE.
EXTREMELY ISOLATED CONVECTION HAS FORMED IN THIS BAND AS IT
MARCHES TO THE SE AT AROUND 20 KTS. AT THE SFC...DEWPOINTS ARE
POOLING ACROSS THE AREA AND RELATIVELY CLEAR SKIES REMAIN ACROSS
THE AREA. WITH THE POOLING MOISTURE....TEMPS HAVE BEEN SLOW TO
DROP ACROSS THE AREA. GUIDANCE SUGGESTS AN H85 THETAE PUSH OF
NEAR 50 DEGREES INTO THE AREA NEAR 12Z. THIS AND THE VORT MAX WILL
DOMINATE OUR WEATHER IN THE NEXT 6 TO 12 HOURS.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 329 AM CDT SUN AUG 2 2015
MAIN FORECAST CONCERN FOR THE SHORT ARE THE CHANCES FOR
THUNDERSTORMS AND RAIN TODAY. THERE ARE TWO CHANCES WITH THE FIRST
ONE EITHER ONGOING AT 12Z OR STARTING SHORTLY THEREAFTER. THE
OTHER IS ASSOCIATED WITH A COLD FRONT THAT WILL MOVE THROUGH THE
AREA TODAY AND INTO TONIGHT. SOME OF THE STORMS LATER THIS
AFTERNOON AND EVENING COULD BE STRONG TO SEVERE.
THIS MORNING THE ACCAS DECK MOVING INTO THE AREA WILL ENCOUNTER AN
H85 THETAE PUSH. THESE TWO ARE FORECAST TO BE COINCIDENT ACROSS
THE CWA NEAR 12Z. THIS COULD LEAD TO THE DEVELOPMENT OF SHOWERS
AND THUNDERSTORMS ACROSS THE AREA. LARGE SCALE MODELS HINT AT THIS
POSSIBLY HAPPENING...HOWEVER THE MESOSCALE NATURE OF THE FORCINGS
ARE DIFFICULT FOR THE MODELS TO HANDLE CORRECTLY. PERUSING THE
CAMS...WHICH DO BETTER WITH MESOSCALE FEATURES...IT IS CLEAR THAT
THESE MODELS DO SUGGEST ADDITIONAL THUNDERSTORM DEVELOPMENT THIS
MORNING WITH THE WAVE. AT THIS TIME...THESE STORMS ARE NOT
EXPECTED TO BE SEVERE. A STRONG STORM WITH SMALL HAIL COULD BE
POSSIBLE. I DO NOT HAVE HIGH CONFIDENCE IN THIS OCCURRING SO
DECIDED TO GO WITH SCHC POPS UNTIL THE ACCAS BECOMES BETTER
AGITATED. ANY STORMS THIS AM COULD LEAVE OFBS THAT MAY
INFLUENCE CONVECTION LATER.
THIS AFTERNOON...GUIDANCE SUGGESTS THAT MIXING WILL RESULT IN HIGH
TEMPS IN THE 90S ACROSS THE AREA. SOUNDINGS INDICATE THE EML HAS
RESULTED IN DRIER AIR ALOFT. AS THIS DRIER AIR IS MIXED DOWN...THE
TEMPS SHOULD INCREASE AND DEWPOINTS SHOULD LOWER. USED MOSGUIDE
FOR THE DEWPOINTS AS THEY SEEMED TO HAVE A BETTER HANDLE ON WHAT
WAS GOING ON NOW AND MIXING THE DEWPOINTS LOWER THIS PM. AS A
RESULT...HEAT INDICES WILL REMAIN BELOW CRITERIA.
LATE THIS AFTERNOON A COLD FRONT WILL MOVE THROUGH THE AREA.
LOOKING AT THE THUNDERSTORM POTENTIAL...THERE WILL BE SUFFICIENT
DEEP LAYER SHEAR FOR ISOLATED CELLS. WITH THE MAIN FORCING TO THE
NORTH...THESE STORMS MAY BE SLOWER TO GROW UPSCALE INTO A MCS.
LAPSE RATES IN THE MID LEVELS SUGGEST THAT HAIL WILL BE THE MAIN
THREAT. WITH THE HIGH TEMPS AND LIKELY HIGHER STORM
BASES...DAMAGING WINDS COULD ALSO BE POSSIBLE. LOW LEVEL SHEAR
AND HODOS ARE INDICATIVE OF THE POSSIBILITY OF TORNADOES AS WELL.
IN FACT THEY ARE VERY FAVORABLE FOR POSSIBLE TORNADOES.
HOWEVER...THE THERMODYNAMIC ENVIRONMENT IS NOT. I THINK THE THREAT
OF TORNADOES IS HIGHER WITH AN MCS INSTEAD OF A SUPERCELL STORM
THAT MAY BE THE FIRST MODE OF DEVELOPMENT. REGARDLESS THERE IS A
THREAT FOR SEVERE WEATHER FROM THESE STORMS.
LOOKING AT THE CAMS...THE NAM 4KM HAS THE BULK OF THE STORMS AND
BOWING STRUCTURES ACROSS WI AND E IL. THIS MODEL POPS SHORT LIVED
ISOLATED CELLS THAT STRUGGLE TO GROW UPSCALE INTO A MCS
STRUCTURES. THE WRFNMM AND ARW ARE EERILY SIMILAR IN WHICH A
FRONTAL MCS COMES THROUGH OUR AREA INSTEAD OF TO THE EAST.
REGARDLESS THESE MODELS PRODUCE STORMS AND THUS GIVE ME HIGHER
CONFIDENCE THAT CONVECTION WILL OCCUR. DID NOT GO HIGHER THAN CHC
AS I DO NOT HAVE AN IDEA OF WHICH OF THE SOLUTIONS WILL OCCUR.
LATER SHIFTS MAY BE ABLE TO INCREASE POPS ACROSS THE AREA AS THE
DAY PROGRESSES AND A CLEARER SOLUTION IS SEEN.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN AUG 2 2015
MONDAY AND MONDAY NIGHT... NORTHWEST FLOW ALOFT WILL DOMINATE EARLY IN THE
WEEK AS ANOMALOUSLY DEEP UPPER LOW (500 MB HEIGHTS OF 550-555 DECAMETERS
EQUATING TO ROUGHLY 2+ STANDARD DEVIATIONS BELOW CLIMO PER NAEFS) REMAINS
PARKED NEAR QUEBEC. THIS FLOW PATTERN COUPLED WITH HIGH PRESSURE RIDGE
BUILDING IN WILL RESULT IN COOLER (NEAR NORMAL) AND DRIER CONDITIONS
TO START THE WEEK. A SURFACE FRONT IS ANTICIPATED TO STALL OUT FROM THE
CENTRAL PLAINS TO THE APPALACHIANS BY MONDAY EVENING. ISENTROPIC LIFT AND
WEAK LOW AMPLITUDE SHORTWAVES WILL PROVIDE FOCUS FOR PRECIPITATION CHANCES
NEAR AND ON COOL SIDE OF BOUNDARY...WITH THE FAR SOUTHERN CWA POTENTIALLY IN
CLOSE PROXIMITY TO SOME OF THIS ACTIVITY.
TUESDAY AND TUESDAY NIGHT... OVERALL PATTERN NOT SHOWING MUCH CHANGE
DURING THIS PERIOD WITH UPPER LOW SLOW MOVING THROUGH ONTARIO... AND
CWA STAYING ON COOL SIDE OF STALLED FRONTAL ZONE FROM THE PLAINS THROUGH THE
MID-MISSISSIPPI VALLEY. THUS... MORE OF THE SAME WITH PLEASANT CONDITIONS
WITH NEAR TO SLIGHTLY BELOW NORMAL TEMPS AND COMFORTABLE HUMIDITY LEVELS...
AND ANY RAIN CHANCES MAINLY TO OUR SOUTH/WEST IN VICINITY OF STALLED FRONT
WITH SOUTHERN CWA STANDING ANY CHANCES FOR RAIN BEING IN CLOSER PROXIMITY TO
BOUNDARY.
WEDNESDAY THROUGH SATURDAY... CONTINUED GRADUAL DRAWN DOWN ON TEMPS TO BELOW
NORMAL EXPECTED INTO LATE WEEK WITH INFLUX OF COOLER AIR (850 MB TEMPS
LOWERING INTO RANGE OF 12-16C) IN WAKE OF DEPARTING ONTARIO UPPER LOW.
IN ADDITION...LIKELIHOOD OF INTERVALS OF CLOUDINESS WITH SERIES OF UPPER LEVEL
DISTURBANCES PROPAGATING THROUGH REGION IN THE SEMI-ZONAL TO NORTHWEST FLOW
TO AID IN KEEPING TEMPS BELOW NORMAL. WITH SURFACE FRONT NEARBY WILL MAINTAIN
RAIN CHANCES THROUGH THURSDAY THEN TRENDS SUPPORT DRYING OUT LATE WEEK INTO THE
WEEKEND WITH ANOTHER BOUT OF GREAT LAKES RIDGING AND INFLUX OF COOLER...DRIER AIR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1145 PM CDT SAT AUG 1 2015
VFR CONDITIONS WILL BE SEEN THROUGH 15Z/02. THE PROBABILITY OF A
SHRA OR TSRA AFFECTING A TAF SITE THROUGH SUNRISE IS UNDER 10
PERCENT. IF A SHRA/TSRA WOULD AFFECT A TAF SITE...KDBQ WOULD HAVE
A SLIGHTLY BETTER CHANCE...AND ONLY A BRIEF PERIOD OF MVFR
CONDITIONS MIGHT BE SEEN. AFT 15Z/02 VFR CONDITIONS ARE EXPECTED
TO CONTINUE. A NEW ROUND OF CONVECTION IS EXPECTED AFT 18Z/02
ACROSS NORTHERN ILLINOIS.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...GIBBS
SYNOPSIS...GIBBS
SHORT TERM...GIBBS
LONG TERM...05
AVIATION...08
AREA FORECAST DISCUSSION
NWS JACKSON KY
1038 AM EDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1038 AM EDT SUN AUG 2 2015
MUCH OF THE FOG THAT DEVELOPED ACROSS THE RIVER VALLEYS THIS
MORNING HAS DISSIPATED. WE ARE LEFT WITH MOSTLY SUNNY TO SUNNY
SKIES UNDER SURFACE HIGH PRESSURE. FORECAST IS ON TRACK AT THIS
POINT WITH ONLY MINOR ADJUSTMENTS MADE OVERALL TOWARDS LATEST OBS
AND TRENDS.
UPDATE ISSUED AT 700 AM EDT SUN AUG 2 2015
TOUCHED UP THE GRIDS THIS MORNING BASED ON THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 350 AM EDT SUN AUG 2 2015
07Z SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER CENTRAL
KENTUCKY. THIS IS HELPING TO KEEP THE SKY MOSTLY CLEAR ACROSS THE
STATE...BUT A SMATTERING OF MID LEVEL CLOUDS ARE DRIFTING OVER
EAST KENTUCKY AND OUT OF THE AREA ATTM. SIMILAR TO THE PAST FEW
NIGHTS...AN INVERSION HAS SET UP WHILE GOOD RADIATIONAL COOLING IS
UNDERWAY. THIS HAS LED TO ANOTHER NIGHT OF RIDGE TO VALLEY
TEMPERATURE DIFFERENCES WITH SOME UPPER 50S FOUND IN THE DEEPER
SPOTS WHILE HILLTOPS ARE RUNNING IN THE MID 60S. WINDS REMAIN
LIGHT TO CALM ACROSS EAST KENTUCKY WITH NOT MUCH EVIDENCE OF FOG
OUT THERE YET. HOWEVER...AGAIN SIMILAR TO THE PAST FEW NIGHTS...
EXPECT THE FOG TO FORM IN THE RIVER VALLEYS BEFORE DAWN ALONG WITH
LOCALLY DENSE PATCHES.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS A BROAD AREA OF
TROUGHING CONTINUES OVER SOUTH CENTRAL CANADA AND DOWN INTO THE
OHIO VALLEY ACROSS TO NEW ENGLAND. A WIGGLE AT THE CORE OF THE
TROUGH TO THE NORTH WILL SEND A LARGE AMOUNT OF ENERGY INTO THE
GREAT LAKES ON MONDAY ALONG WITH A MID LEVEL GRADIENT THAT
TIGHTENS...RESULTING IN FASTER FLOW THROUGH THE OHIO VALLEY. GIVEN
THE AGREEMENT ALOFT WILL FOLLOW A BLENDED SOLUTION WITH EMPHASIS
ON THE HRRR AND NAM12 EARLY ON AND THE BROADER CONSENSUS LATER.
SENSIBLE WEATHER WILL FEATURE ANOTHER PLEASANT DAY WITH FAIRLY LOW
AND COMFORTABLE HUMIDITY LEVELS AND HIGHS GENERALLY IN THE MID
80S UNDER MOSTLY SUNNY SKIES. THIS WILL LEAD INTO ONE MORE NIGHT
OF GOOD RADIATIONAL COOLING AND RIDGE TO VALLEY TEMPERATURE
DIFFERENCES INTO MONDAY MORNING...ALONG WITH PATCHY VALLEY FOG
TOWARDS DAWN. BY MONDAY...THOUGH...THE SFC PATTERN WILL CHANGE
WITH A COLD FRONT PRESSING SOUTH THROUGH THE OHIO VALLEY AND
TOWARD EAST KENTUCKY. THIS WILL LIKELY KICK OFF SHOWERS AND
THUNDERSTORMS NORTH OF THE STATE THAT SHOULD HELP TO SPAWN
ADDITIONAL STORMS TO THE SOUTH WITH TIME THROUGH THE DAY. ANY
STORMS THAT MANAGE TO DEVELOP OUT AHEAD OF THE FRONT IN EAST
KENTUCKY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE OWING
TO HIGH CAPES AND STRENGTHENING MID LEVEL WINDS. THE BEST CHANCES
WILL BE OVER OUR NORTHERN ZONES CLOSER TO THE FRONT AND SPC HAS
INDICATED A SLIGHT RISK FOR SEVERE STORMS THERE. WILL HIGHLIGHT
THIS CONCERN IN THE FORTHCOMING HWO.
STARTED WITH THE SHORTBLEND MODEL FOR THE T/TD/WIND GRIDS THROUGH
THE DAY FOLLOWED BY THE SUPERBLEND INTO MONDAY. DID MAKE SOME
SIGNIFICANT ADJUSTMENTS TO TEMPERATURES THIS MORNING AND TONIGHT
WITH RESPECT TO RIDGE AND VALLEY DIFFERENCES. AS FOR POPS...KEPT
THEM LOW AND IN LINE WITH THE DRY GUIDANCE INTO MONDAY MORNING.
DID GO A BIT HIGHER THAN THE MET AND MAV NUMBERS FOR MONDAY
AFTERNOON TO ACCOUNT FOR THE POTENTIAL INTRUSION OF STORMS...
ORGANIZED OR OTHERWISE...FROM THE NORTH BY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 AM EDT SUN AUG 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON MONDAY NIGHT WITH THE UPPER
LEVEL PATTERN MAINTAINING A RIDGE OVER THE WEST AND THE LONGWAVE
TROUGH OVER THE EASTERN CONUS. A CLOSED LOW OVER THE HUDSON BAY AREA
WILL GRADUALLY SHIFT OFF TO THE EAST THROUGH THE EXTENDED AS BY
THURSDAY...A SERIES OF STRONGER TROUGHS COME ASHORE OVER THE WEST AS
THE WESTERN RIDGE BEGINS TO WEAKEN A BIT AND SHIFT EAST. THIS
THROUGH THE LAST PORTION OF THE EXTENDED WILL BE THE FORECAST
CHALLENGE AS THE BASE OF THE EASTERN TROUGH SETS UP OVER THE MID MS
VALLEY AND THROUGH KY. THE GFS AND EURO DOES ALIGN A BIT WITH THIS
SOLUTION.
CLOSER TO THE SURFACE...THE FRONT THAT HAS PASSED THROUGH ON MONDAY
WILL LAG ACROSS NORTHERN KENTUCKY AS A STATIONARY BOUNDARY DEVELOPS.
THIS AREA BECOMES A FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT AS
THE BOUNDARY SLIDES FURTHER SOUTH THROUGH THE DAY ON TUESDAY AND
TUESDAY NIGHT. BY WEDNESDAY...NORTHWEST FLOW SETS UP OVER THE AREA
AS A SERIES OF UPPER LEVEL WAVES TOPPLE OVER THE THE TOP OF THE
WESTERN RIDGE AND TRACK SOUTHEAST INTO THE OH VALLEY. THE SUPER
BLEND HAS THIS IN IT/S SOLUTION AS WELL WITH THE PATTERN FAVORABLE
FOR NOCTURNAL THUNDERSTORMS AS WELL...ESPECIALLY IF THIS PATTERN FOR
MCS/S REMAIN...WHICH SEEMS LIKELY BASED UPON THE GFS AND EURO
SOLUTIONS . THUS WILL STAY CLOSE TO THE SUPER BLENDS SOLUTION
WEDNESDAY THROUGH FRIDAY KEEPING HIGH CHANCE TO LIKELY POPS DURING
THIS PERIOD.
TOWARDS THE END OF THE EXTENDED ON FRIDAY AND SATURDAY...THE UPPER
LEVEL PATTERN LOSES A BIT AMPLITUDE AND BECOMES MORE ACTIVE AS
ANOTHER SHORTWAVE TAKES AIM AT THE OH VALLEY. HOWEVER...THE GFS AND
EURO DO DIVERGE TOWARDS THE END OF THE EXTENDED. THUS...LACKING
CONFIDENCE...WILL GO NEAR OR SLIGHTLY BELOW THE SUPER BLEND ON POPS.
THE LINGERING TROUGH OVER THE EAST AND SAGGING SOUTH THROUGH THE
EXTENDED WILL KEEP HIGHS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME
OF YEAR. IN SHORT...THE WEDNESDAY THROUGH FRIDAY PERIOD SEEMS TO BE
QUITE ACTIVE AND WET WITH THE END OF THE FORECAST POSSIBLY
CONTINUING THIS TREND WITH A COOLING TREND AS WELL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 715 AM EDT SUN AUG 2 2015
A RIDGE OF HIGH PRESSURE WILL KEEP MOSTLY CLEAR SKIES AND LIGHT
WINDS IN PLACE ACROSS THE AREA FOR THE TAF PERIOD. THE BULK OF
ANY FOG AROUND THIS MORNING AND AGAIN TOWARD DAWN MONDAY SHOULD
BE CONFINED TO VALLEY FLOORS AND NEAR BODIES OF WATER. AS
SUCH...THE MAJORITY OF THE TAF SITES SHOULD ALL REMAIN FREE OF FOG
THIS MORNING AND INTO MONDAY MORNING. THE EXCEPTION WILL PROBABLY
BE AT SME AND SYM WHERE SOME MVFR OR BRIEF IFR FOG WILL BE
POSSIBLE. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD ALONG WITH LIGHT AND VARIABLE WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
715 AM EDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 700 AM EDT SUN AUG 2 2015
TOUCHED UP THE GRIDS THIS MORNING BASED ON THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 350 AM EDT SUN AUG 2 2015
07Z SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER CENTRAL
KENTUCKY. THIS IS HELPING TO KEEP THE SKY MOSTLY CLEAR ACROSS THE
STATE...BUT A SMATTERING OF MID LEVEL CLOUDS ARE DRIFTING OVER
EAST KENTUCKY AND OUT OF THE AREA ATTM. SIMILAR TO THE PAST FEW
NIGHTS...AN INVERSION HAS SET UP WHILE GOOD RADIATIONAL COOLING IS
UNDERWAY. THIS HAS LED TO ANOTHER NIGHT OF RIDGE TO VALLEY
TEMPERATURE DIFFERENCES WITH SOME UPPER 50S FOUND IN THE DEEPER
SPOTS WHILE HILLTOPS ARE RUNNING IN THE MID 60S. WINDS REMAIN
LIGHT TO CALM ACROSS EAST KENTUCKY WITH NOT MUCH EVIDENCE OF FOG
OUT THERE YET. HOWEVER...AGAIN SIMILAR TO THE PAST FEW NIGHTS...
EXPECT THE FOG TO FORM IN THE RIVER VALLEYS BEFORE DAWN ALONG WITH
LOCALLY DENSE PATCHES.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS A BROAD AREA OF
TROUGHING CONTINUES OVER SOUTH CENTRAL CANADA AND DOWN INTO THE
OHIO VALLEY ACROSS TO NEW ENGLAND. A WIGGLE AT THE CORE OF THE
TROUGH TO THE NORTH WILL SEND A LARGE AMOUNT OF ENERGY INTO THE
GREAT LAKES ON MONDAY ALONG WITH A MID LEVEL GRADIENT THAT
TIGHTENS...RESULTING IN FASTER FLOW THROUGH THE OHIO VALLEY. GIVEN
THE AGREEMENT ALOFT WILL FOLLOW A BLENDED SOLUTION WITH EMPHASIS
ON THE HRRR AND NAM12 EARLY ON AND THE BROADER CONSENSUS LATER.
SENSIBLE WEATHER WILL FEATURE ANOTHER PLEASANT DAY WITH FAIRLY LOW
AND COMFORTABLE HUMIDITY LEVELS AND HIGHS GENERALLY IN THE MID
80S UNDER MOSTLY SUNNY SKIES. THIS WILL LEAD INTO ONE MORE NIGHT
OF GOOD RADIATIONAL COOLING AND RIDGE TO VALLEY TEMPERATURE
DIFFERENCES INTO MONDAY MORNING...ALONG WITH PATCHY VALLEY FOG
TOWARDS DAWN. BY MONDAY...THOUGH...THE SFC PATTERN WILL CHANGE
WITH A COLD FRONT PRESSING SOUTH THROUGH THE OHIO VALLEY AND
TOWARD EAST KENTUCKY. THIS WILL LIKELY KICK OFF SHOWERS AND
THUNDERSTORMS NORTH OF THE STATE THAT SHOULD HELP TO SPAWN
ADDITIONAL STORMS TO THE SOUTH WITH TIME THROUGH THE DAY. ANY
STORMS THAT MANAGE TO DEVELOP OUT AHEAD OF THE FRONT IN EAST
KENTUCKY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE OWING
TO HIGH CAPES AND STRENGTHENING MID LEVEL WINDS. THE BEST CHANCES
WILL BE OVER OUR NORTHERN ZONES CLOSER TO THE FRONT AND SPC HAS
INDICATED A SLIGHT RISK FOR SEVERE STORMS THERE. WILL HIGHLIGHT
THIS CONCERN IN THE FORTHCOMING HWO.
STARTED WITH THE SHORTBLEND MODEL FOR THE T/TD/WIND GRIDS THROUGH
THE DAY FOLLOWED BY THE SUPERBLEND INTO MONDAY. DID MAKE SOME
SIGNIFICANT ADJUSTMENTS TO TEMPERATURES THIS MORNING AND TONIGHT
WITH RESPECT TO RIDGE AND VALLEY DIFFERENCES. AS FOR POPS...KEPT
THEM LOW AND IN LINE WITH THE DRY GUIDANCE INTO MONDAY MORNING.
DID GO A BIT HIGHER THAN THE MET AND MAV NUMBERS FOR MONDAY
AFTERNOON TO ACCOUNT FOR THE POTENTIAL INTRUSION OF STORMS...
ORGANIZED OR OTHERWISE...FROM THE NORTH BY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 AM EDT SUN AUG 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON MONDAY NIGHT WITH THE UPPER
LEVEL PATTERN MAINTAINING A RIDGE OVER THE WEST AND THE LONGWAVE
TROUGH OVER THE EASTERN CONUS. A CLOSED LOW OVER THE HUDSON BAY AREA
WILL GRADUALLY SHIFT OFF TO THE EAST THROUGH THE EXTENDED AS BY
THURSDAY...A SERIES OF STRONGER TROUGHS COME ASHORE OVER THE WEST AS
THE WESTERN RIDGE BEGINS TO WEAKEN A BIT AND SHIFT EAST. THIS
THROUGH THE LAST PORTION OF THE EXTENDED WILL BE THE FORECAST
CHALLENGE AS THE BASE OF THE EASTERN TROUGH SETS UP OVER THE MID MS
VALLEY AND THROUGH KY. THE GFS AND EURO DOES ALIGN A BIT WITH THIS
SOLUTION.
CLOSER TO THE SURFACE...THE FRONT THAT HAS PASSED THROUGH ON MONDAY
WILL LAG ACROSS NORTHERN KENTUCKY AS A STATIONARY BOUNDARY DEVELOPS.
THIS AREA BECOMES A FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT AS
THE BOUNDARY SLIDES FURTHER SOUTH THROUGH THE DAY ON TUESDAY AND
TUESDAY NIGHT. BY WEDNESDAY...NORTHWEST FLOW SETS UP OVER THE AREA
AS A SERIES OF UPPER LEVEL WAVES TOPPLE OVER THE THE TOP OF THE
WESTERN RIDGE AND TRACK SOUTHEAST INTO THE OH VALLEY. THE SUPER
BLEND HAS THIS IN IT/S SOLUTION AS WELL WITH THE PATTERN FAVORABLE
FOR NOCTURNAL THUNDERSTORMS AS WELL...ESPECIALLY IF THIS PATTERN FOR
MCS/S REMAIN...WHICH SEEMS LIKELY BASED UPON THE GFS AND EURO
SOLUTIONS . THUS WILL STAY CLOSE TO THE SUPER BLENDS SOLUTION
WEDNESDAY THROUGH FRIDAY KEEPING HIGH CHANCE TO LIKELY POPS DURING
THIS PERIOD.
TOWARDS THE END OF THE EXTENDED ON FRIDAY AND SATURDAY...THE UPPER
LEVEL PATTERN LOSES A BIT AMPLITUDE AND BECOMES MORE ACTIVE AS
ANOTHER SHORTWAVE TAKES AIM AT THE OH VALLEY. HOWEVER...THE GFS AND
EURO DO DIVERGE TOWARDS THE END OF THE EXTENDED. THUS...LACKING
CONFIDENCE...WILL GO NEAR OR SLIGHTLY BELOW THE SUPER BLEND ON POPS.
THE LINGERING TROUGH OVER THE EAST AND SAGGING SOUTH THROUGH THE
EXTENDED WILL KEEP HIGHS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME
OF YEAR. IN SHORT...THE WEDNESDAY THROUGH FRIDAY PERIOD SEEMS TO BE
QUITE ACTIVE AND WET WITH THE END OF THE FORECAST POSSIBLY
CONTINUING THIS TREND WITH A COOLING TREND AS WELL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 715 AM EDT SUN AUG 2 2015
A RIDGE OF HIGH PRESSURE WILL KEEP MOSTLY CLEAR SKIES AND LIGHT
WINDS IN PLACE ACROSS THE AREA FOR THE TAF PERIOD. THE BULK OF
ANY FOG AROUND THIS MORNING AND AGAIN TOWARD DAWN MONDAY SHOULD
BE CONFINED TO VALLEY FLOORS AND NEAR BODIES OF WATER. AS
SUCH...THE MAJORITY OF THE TAF SITES SHOULD ALL REMAIN FREE OF FOG
THIS MORNING AND INTO MONDAY MORNING. THE EXCEPTION WILL PROBABLY
BE AT SME AND SYM WHERE SOME MVFR OR BRIEF IFR FOG WILL BE
POSSIBLE. OTHERWISE...VFR CONDITIONS WILL PREVAIL THROUGH THE
PERIOD ALONG WITH LIGHT AND VARIABLE WINDS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...GREIF
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1153 AM EDT SUN AUG 2 2015
.UPDATE...
FORECAST REMAINS IN GOOD SHAPE AS CONVECTIVE EVOLUTION TO OUR
NORTH HAS BEEN FAIRLY PREDICTABLE TO THIS POINT. SEVERAL CLUSTERS
OF STORMS CONTINUE TO PEEL EASTWARD ACROSS NORTHERN WISCONSIN ON
INTO THE UP AND NORTHERN LOWER MICHIGAN. THUNDERSTORM CHANCES WILL
INCREASE OVER THE NORTHERN CWA THIS AFTERNOON AS THE FLOW OF WARM
AND MOIST AIR PERSISTS AND A LARGE OUTFLOW BOUNDARY ALONG THE
SOUTHERN EDGE OF STORM COMPLEXES TO THE NORTH SETTLES INTO THE
FORECAST AREA AND PROVIDES FOCUS FOR THIS INCREASINGLY UNSTABLE
AIRMASS. WHILE AN ISOLATED STORM CANNOT BE RULED OUT AS FAR SOUTH
AS M 59 LATER THIS AFTERNOON...MOST ACTIVITY WILL REMAIN NORTH OF
THE I-69 CORRIDOR.
IT LOOKS INCREASINGLY LIKE THE NEXT ROUND OF THUNDERSTORMS WILL
ACTUALLY OVERLAP WITH THIS ONGOING ACTIVITY AS OPPOSED TO BEING A
MORE DISTINCT EPISODE. A CONTINUED FLOW OF MOIST/UNSTABLE AIR
ALONG THE AFOREMENTIONED OUTFLOW BOUNDARY SHOULD MAINTAIN FAIRLY
CONSISTENT CONVECTION ALONG/NORTH OF THE CWA INTO EARLY THIS
EVENING WITH ADDITIONAL DEVELOPING ACTIVITY ALONG APPROACHING
COLD FRONT THEN SPREADING INTO THE AREA FROM NORTHERN LOWER
MICHIGAN AND WISCONSON DURING THE COURSE OF THE EVENING...WHICH
WILL ACT TO DRAG EXISTING CONVECTION ALONG THE NORTHERN BORDER
SOUTHWARD INTO THE AREA.
NET RESULT WILL BE THE SAME AS STORM CHANCES INCREASE FROM NORTH
TO SOUTH ACROSS THE AREA FROM MID TO LATE EVENING. TIMING FOR
LARGEST THREAT OF STORMS FOR METRO DETROIT STILL APPEARS TO BE
MAINLY AFTER 10 PM AND PERHAPS CLOSER TO MIDNIGHT FOR MANY
LOCALES. WITH ANY LUCK...DECLINING INSTABILITY AT THIS LATER HOUR
WILL TAKE SOME PUNCH OUT OF THE LINE OF STORMS THAT EVENTUALLY
EVOLVES AND PROGRESSES INTO THE AREA LATER THIS EVENING. THAT
SAID...THE THREAT OF SEVERE WEATHER WILL PERSIST GIVEN THE STRONG
WIND FIELD AND AT LEAST A MODERATELY UNSTABLE AIRMASS AT THAT
POINT.
&&
.AVIATION...ISSUED 633 AM EDT SUN AUG 2 2015
STRENGTHENING SWLY WINDS WILL GUST TO AROUND 25 KTS LATE THIS
MORNING INTO AFTN IN ADVANCE OF AN APPROACHING TROUGH AND COLD
FRONT. INCREASING INSTABILITY WILL SUPPORT POTENTIAL FOR TSTORMS TO
IMPACT MAINLY KMBS/KFNT THIS AFTERNOON WHILE REMAINING TERMINALS
SHOULD REMAIN CAPPED WITH NOTHING MORE THAN HIGH BASED CU. MORE
SIGNIFICANT TSTORM EPISODE POSSIBLE 00Z-06Z TONIGHT AS UPSTREAM
CONVECTION ORGANIZES AND MOVES DOWNSTREAM CARRYING AN ELEVATED
SEVERE THREAT...PARTICULARLY FOR NW AREAS. UNCERTAINTY IS HIGHER IN
DETROIT AREA GIVEN EXPECTED TSTORM ARRIVAL WELL AFTER SUNSET AND
LOSS OF DIURNAL HEATING.
FOR DTW...VERY LOW CHANCE FOR A TSTORM INVOF KDTW 18-00Z WITH
CAPPING EXPECTED TO PREVAIL WARRANTING REMOVAL OF PRIOR PROB30
GROUP. MOST PROBABLE TIME FOR TSTORMS WILL BE 03-06Z IN ADVANCE OF
THE COLD FRONT.
//DTW THRESHOLD PROBABILITIES...
* LOW FOR TSTORMS THIS AFTN. MEDIUM AFTER 03Z TONIGHT.
&&
.PREV DISCUSSION...ISSUED 526 AM EDT SUN AUG 2 2015
UPDATE...
A REFINEMENT OF THOUGHTS AFTER PERUSING FRESH ARRIVING HIGH
RESOLUTION GUIDANCE, PARTICULARLY THE RAP, HRRR AND 00Z 3KM
EXPERIMENTAL NAM WHICH APPEAR TO BE SHEDDING SOME LIGHT ON THIS
AFTERNOON AND EVENING`S SEVERE POTENTIAL. ALTHOUGH OVERALL FORECAST
REASONING HAS NOT CHANGED, NEW INFORMATION IS INCREASING CONFIDENCE
THAT AFTERNOON CONVECTION WILL REMAIN CONFINED TO NORTHERN AREAS
ALONG THE NOSE OF THE DEVELOPING LOW-LEVEL JET WHILE AREAS SOUTH OF
M59 REMAIN CAPPED THUS INHIBITING PREMATURE OVERTURNING.
IN ADDITION TO THE PRIMARY THREAT OF UPSCALE GROWTH OF CONVECTION
INTO AN ORGANIZED MCS, A FEW STORMS COULD ALSO DEVELOP IN ADVANCE OF
THIS LINE WITHIN THE CORRIDOR PRECEDING WARM ADVECTION. THIS
PREFRONTAL CONVECTION WILL HAVE STEEP LAPSE RATES AND AN APPRECIABLE
RESERVOIR OF INSTABILITY WITH WHICH TO WORK. THE OFT CONSERVATIVE
07Z RAP INDICATING 0-1KM MLCAPE APPROACHING 2500 J/KG IN MIDLAND/BAY
COUNTY BY 22Z. IN ADDITION, STRENGTHENING SWLY FLOW WILL SUPPORT
ELEVATED BULK SHEAR DURING THIS TIME THUS POTENTIALLY SUPPORTING A
FEW SUPERCELLS AS UPSTREAM CONVECTION ORGANIZES OVER WISCONSIN, LAKE
MICHIGAN, AND NORTHERN LOWER MICHIGAN. GIVEN WELL MIXED/DEEP
BOUNDARY LAYER INDICATED ON FORECAST SOUNDINGS, IT APPEARS THAT A
POTENTIALLY SIGNIFICANT/70MPH, IF RELATIVELY ISOLATED, WIND THREAT
MAY EXIST MAINLY INVOF THE SAGINAW VALLEY IN ADVANCE OF THE MAIN
LINE AS EARLY AS 21/22Z. FOR THE SAME REASON, TORNADO THREAT WOULD
APPEAR LIMITED DUE TO HIGH LCLS. THOUGH THIS AFTN/EVENING`S
CONVECTIVE TRENDS WILL STILL BE CRITICAL, LATEST GUIDANCE DOES
SUPPORT THE OFFICIAL FORECAST STRONGLY ENOUGH TO CONSIDER
ADVERTISING A THREAT FOR 70 MPH WIND GUSTS CONDITIONAL ON MCS
ORGANIZATION. WILL ALLOW TIME FOR UPDATED SPC DAY 1 AND FOR DAY CREW
TO EVALUATE LATEST TRENDS AND HIGH RES GUIDANCE BEFORE ELEVATING
WORDING IN THE HWO AND OTHER PRODUCTS.
FINALLY, AS NOTED IN THE ORIGINAL MORNING FORECAST PACKAGE, A
LIMITED SEVERE THREAT WILL EXIST WITH ANY CONVECTION THAT TRAVERSES
LAND ACROSS THE NORTH DURING THE AFTERNOON HOURS. IF LATEST RAP RUNS
ARE ANY INDICATION, THE THERMODYNAMIC ENVIRONMENT MAY EVOLVE A BIT
FASTER THAN PREVIOUSLY FORECAST YIELDING INCREASED CONFIDENCE IN
SEVERE WIND POTENTIAL AT LEAST OVER THE THUMB PERHAPS AS EARLY AS
18Z SHOULD UPSTREAM CONVECTION DEVELOP WITHIN FAVORABLE WAA/STEEP
LAPSE RATE ENVIRONMENT.
&&
.PREV DISCUSSION...ISSUED 252 AM EDT SUN AUG 2 2015
SHORT TERM...TODAY AND TONIGHT
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MN AND WI DURING THE
PREDAWN HOURS AS A FAST-MOVING LEAD SHORTWAVE PROVIDES FORCING
WITHIN THE STEEP LAPSE RATE ENVIRONMENT BEING DRAWN EAST BY BROAD
CYCLONIC WNW FLOW. THIS ENVIRONMENT WILL RACE EAST THROUGH THE
AFTERNOON FOCUSING A CORRIDOR OF CONVECTION ACROSS PRIMARILY ACROSS
LAKE HURON AND NORTHERN LOWER MICHIGAN. SOUTHEASTERN PORTIONS OF THE
CWA WILL REMAIN LARGELY CAPPED THROUGH PEAK HEATING AS H85
TEMPERATURES RISE WELL INTO THE UPPER TEENS SUPPORTING HIGHS
APPROACHING 90F. HOWEVER, SLIGHTLY WEAKER CAPPING/BETTER FORCING
ACROSS THE NORTH WARRANT AT LEAST A HIGH CHC POP FROM THE SAGINAW
VALLEY INTO THE THUMB, INCREASING TO LIKELY BY LATE THIS AFTN. THIS
ACTIVITY WILL CARRY AT LEAST A LOW END SEVERE RISK 18-00Z NORTH OF
THE I-69 CORRIDOR AS IT WILL RESIDE ALONG THE EASTERN PERIPHERY MORE
STRONGLY SHEARED SWLY FLOW AND AS SURFACE TDS RISE INTO THE MID AND
UPPER 60S SUPPORTING MODERATE DESTABILIZATION. LATEST HRRR RUNS HAVE
A DEPICTION SIMILAR TO EXPECTATIONS, PARTICULARLY WRT TO EXPECTED
SOUTHWARD EXTENT. MEANWHILE 4KM SPC RUN APPEARS ENTIRELY TOO
GENEROUS WITH CONVECTIVE COVERAGE/EVOLUTION WITHIN STRONGLY CAPPED
AREAS.
SECOND AND POTENTIALLY GREATER SEVERE THREAT MAY EXIST TONIGHT,
LARGELY CONDITIONAL ON EXTENT OF PRECEDING AFTERNOON CONVECTION AND
QUALITY OF RECOVERY. DEVELOPING STRONG SWLY FLOW IN ADVANCE OF
PRIMARY TROUGH AXIS WILL CERTAINLY GIVE THE EXPECTED GENESIS AREA
OVER NORTHERN LOWER OR CENTRAL MI A DECENT SHOT AT RECOVERY BY 00Z.
BETWEEN 00-06Z, STRONG HEIGHT FALLS WILL SPREAD ACROSS THE GREAT
LAKES ELICITING A STRONG LLJ RESPONSE AND IMPRESSIVE MEAN WIND
THROUGH THE LOWER ATMOSPHERE. ASSUMING THE ABSENCE OF STABILIZING
EFFECTS OF EARLIER ACTIVITY, CONVECTIVE INITIATION ALONG THE
INTENSIFYING SURFACE TROUGH WOULD HAVE POTENTIAL TO GROW UPSCALE AND
PROPAGATE INTO AN ENVIRONMENT CHARACTERIZED BY 0-1KM BULK SHEAR
AROUND 40KTS, H7-H5 LAPSE RATES IN EXCESS OF 7.5C/KM, AND 0-1KM
MLCAPE OF 1500 TO 2000 J/KG. THREAT WOULD THEN DIMINISH FROM TOWARD
THE FAR SOUTHEAST AS CONVECTION ENCOUNTERS COMBINATION OF
INCREASINGLY CAPPED MID-LEVELS AND NOCTURNAL STABILIZATION.
LONG TERM...
UPPER LEVEL TROUGH AXIS (EXTENDING FROM LARGE UPPER LEVEL LOW
CENTERED OVER NORTHERN ONTARIO) WILL BE IN PLACE ON MONDAY OVER THE
CENTRAL GREAT LAKES...WITH COLD 500 MB TEMPS AROUND -14 C. THE MAIN
SURFACE COLD FRONT SHOULD CLEAR SOUTHERN MICHIGAN SHORTLY AFTER
12Z...AND SOUTHEAST MICHIGAN WILL BEGIN TO DRY OUT WITH SLOWLY
FALLING DEW PTS. HOWEVER...THERE STILL COULD BE JUST ENOUGH RESIDUAL
LOW LEVEL MOISTURE AROUND TO GENERATE SUFFICIENT INSTABILITY TO POP
ISOLATED-SCATTERED SHOWERS AND MAYBE A THUNDERSTORM...AS THERE IS
ALSO A SECONDARILY COLD FRONT WHICH LOOKS TO BE DROPPING SOUTH FROM
NORTHERN LOWER MICHIGAN...PROVIDING THE BETTER FOCUS. 850 MB TEMPS
STILL IN THE LOWER TEENS ON MONDAY...ALLOWING FOR MAXES AROUND 80
DEGREES...WILL FALL INTO THE UPPER SINGLE NUMBERS TO AROUND 10 C BY
TUESDAY...WHICH SHOULD RESULT IN MAXES HOLDING IN THE MID/UPPER 70S.
A SPOKE OF UPPER LEVEL ENERGY IS FORECASTED TO SWING THROUGH
NORTHERN LOWER MICHIGAN DURING TUESDAY..COUPLED WITH THE DAYTIME
INSTABILITY COULD TOUCH OF A FEW SHOWERS NORTH OF I-69...OTHERWISE
UPPER LEVEL NORTHWEST CONFLUENT FLOW/GENERAL SUBSIDENCE REGIME LOOKS
TO PERSIST AT LEAST INTO WEDNESDAY...SUPPORTING SLOWLY STRENGTHENING
HIGH PRESSURE OVER LOWER MICHIGAN...PROVIDING FAVORABLE RADIATING
NIGHTTIME CONDITIONS ALLOWING MINS TO FALL INTO THE LOW/MID
50S...WITH HIGHS STILL STUCK IN THE 70S FOR WEDNESDAY.
MARINE...
SOUTHWEST WINDS WILL BE INCREASING TODAY AHEAD OF A COLD
FRONT...WITH 25 KNOT GUSTS EXPECTED ACROSS ALL NEARSHORE
WATERS...AND SMALL CRAFT ADVISORIES WILL CONTINUE. COLD FRONT
ARRIVING TONIGHT LOOKS TO TRIGGER THUNDERSTORMS...WHICH COULD BE
SEVERE...PRODUCING WINDS OF 50 KNOTS. WINDS WILL TURN WEST AND THEN
NORTHWEST BEHIND THE FRONT DURING MONDAY. WIND SPEEDS MONDAY LOOK TO
BE GREATEST OVER NORTHERN LAKE HURON...WHERE THEY WILL REACH BETWEEN
15 TO 25 KNOTS MONDAY NIGHT THROUGH TUESDAY NIGHT AS COOLER AIR
SETTLES OVER THE CENTRAL GREAT LAKES REGION. THERE WILL BE A CHANCE
OF SHOWERS AND ISOLATED THUNDERSTORMS OVER LAKE HURON DURING THIS
TIME FRAME AS WELL.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 10 PM EDT THIS EVENING FOR MIZ049.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LHZ421-422-441>443.
LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LEZ444.
&&
$$
UPDATE.......DG
AVIATION.....JVC
SHORT TERM...JVC
LONG TERM....SF
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
633 AM EDT SUN AUG 2 2015
.AVIATION...
STRENGTHENING SWLY WINDS WILL GUST TO AROUND 25 KTS LATE THIS
MORNING INTO AFTN IN ADVANCE OF AN APPROACHING TROUGH AND COLD
FRONT. INCREASING INSTABILITY WILL SUPPORT POTENTIAL FOR TSTORMS TO
IMPACT MAINLY KMBS/KFNT THIS AFTERNOON WHILE REMAINING TERMINALS
SHOULD REMAIN CAPPED WITH NOTHING MORE THAN HIGH BASED CU. MORE
SIGNIFICANT TSTORM EPISODE POSSIBLE 00Z-06Z TONIGHT AS UPSTREAM
CONVECTION ORGANIZES AND MOVES DOWNSTREAM CARRYING AN ELEVATED
SEVERE THREAT...PARTICULARLY FOR NW AREAS. UNCERTAINTY IS HIGHER IN
DETROIT AREA GIVEN EXPECTED TSTORM ARRIVAL WELL AFTER SUNSET AND
LOSS OF DIURNAL HEATING.
FOR DTW...VERY LOW CHANCE FOR A TSTORM INVOF KDTW 18-00Z WITH
CAPPING EXPECTED TO PREVAIL WARRANTING REMOVAL OF PRIOR PROB30
GROUP. MOST PROBABLE TIME FOR TSTORMS WILL BE 03-06Z IN ADVANCE OF
THE COLD FRONT.
//DTW THRESHOLD PROBABILITIES...
* LOW FOR TSTORMS THIS AFTN. MEDIUM AFTER 03Z TONIGHT.
&&
.PREV DISCUSSION...ISSUED 526 AM EDT SUN AUG 2 2015
UPDATE...
A REFINEMENT OF THOUGHTS AFTER PERUSING FRESH ARRIVING HIGH
RESOLUTION GUIDANCE, PARTICULARLY THE RAP, HRRR AND 00Z 3KM
EXPERIMENTAL NAM WHICH APPEAR TO BE SHEDDING SOME LIGHT ON THIS
AFTERNOON AND EVENING`S SEVERE POTENTIAL. ALTHOUGH OVERALL FORECAST
REASONING HAS NOT CHANGED, NEW INFORMATION IS INCREASING CONFIDENCE
THAT AFTERNOON CONVECTION WILL REMAIN CONFINED TO NORTHERN AREAS
ALONG THE NOSE OF THE DEVELOPING LOW-LEVEL JET WHILE AREAS SOUTH OF
M59 REMAIN CAPPED THUS INHIBITING PREMATURE OVERTURNING.
IN ADDITION TO THE PRIMARY THREAT OF UPSCALE GROWTH OF CONVECTION
INTO AN ORGANIZED MCS, A FEW STORMS COULD ALSO DEVELOP IN ADVANCE OF
THIS LINE WITHIN THE CORRIDOR PRECEDING WARM ADVECTION. THIS
PREFRONTAL CONVECTION WILL HAVE STEEP LAPSE RATES AND AN APPRECIABLE
RESERVOIR OF INSTABILITY WITH WHICH TO WORK. THE OFT CONSERVATIVE
07Z RAP INDICATING 0-1KM MLCAPE APPROACHING 2500 J/KG IN MIDLAND/BAY
COUNTY BY 22Z. IN ADDITION, STRENGTHENING SWLY FLOW WILL SUPPORT
ELEVATED BULK SHEAR DURING THIS TIME THUS POTENTIALLY SUPPORTING A
FEW SUPERCELLS AS UPSTREAM CONVECTION ORGANIZES OVER WISCONSIN, LAKE
MICHIGAN, AND NORTHERN LOWER MICHIGAN. GIVEN WELL MIXED/DEEP
BOUNDARY LAYER INDICATED ON FORECAST SOUNDINGS, IT APPEARS THAT A
POTENTIALLY SIGNIFICANT/70MPH, IF RELATIVELY ISOLATED, WIND THREAT
MAY EXIST MAINLY INVOF THE SAGINAW VALLEY IN ADVANCE OF THE MAIN
LINE AS EARLY AS 21/22Z. FOR THE SAME REASON, TORNADO THREAT WOULD
APPEAR LIMITED DUE TO HIGH LCLS. THOUGH THIS AFTN/EVENING`S
CONVECTIVE TRENDS WILL STILL BE CRITICAL, LATEST GUIDANCE DOES
SUPPORT THE OFFICIAL FORECAST STRONGLY ENOUGH TO CONSIDER
ADVERTISING A THREAT FOR 70 MPH WIND GUSTS CONDITIONAL ON MCS
ORGANIZATION. WILL ALLOW TIME FOR UPDATED SPC DAY 1 AND FOR DAY CREW
TO EVALUATE LATEST TRENDS AND HIGH RES GUIDANCE BEFORE ELEVATING
WORDING IN THE HWO AND OTHER PRODUCTS.
FINALLY, AS NOTED IN THE ORIGINAL MORNING FORECAST PACKAGE, A
LIMITED SEVERE THREAT WILL EXIST WITH ANY CONVECTION THAT TRAVERSES
LAND ACROSS THE NORTH DURING THE AFTERNOON HOURS. IF LATEST RAP RUNS
ARE ANY INDICATION, THE THERMODYNAMIC ENVIRONMENT MAY EVOLVE A BIT
FASTER THAN PREVIOUSLY FORECAST YIELDING INCREASED CONFIDENCE IN
SEVERE WIND POTENTIAL AT LEAST OVER THE THUMB PERHAPS AS EARLY AS
18Z SHOULD UPSTREAM CONVECTION DEVELOP WITHIN FAVORABLE WAA/STEEP
LAPSE RATE ENVIRONMENT.
PREV DISCUSSION...ISSUED 252 AM EDT SUN AUG 2 2015
SHORT TERM...TODAY AND TONIGHT
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MN AND WI DURING THE
PREDAWN HOURS AS A FAST-MOVING LEAD SHORTWAVE PROVIDES FORCING
WITHIN THE STEEP LAPSE RATE ENVIRONMENT BEING DRAWN EAST BY BROAD
CYCLONIC WNW FLOW. THIS ENVIRONMENT WILL RACE EAST THROUGH THE
AFTERNOON FOCUSING A CORRIDOR OF CONVECTION ACROSS PRIMARILY ACROSS
LAKE HURON AND NORTHERN LOWER MICHIGAN. SOUTHEASTERN PORTIONS OF THE
CWA WILL REMAIN LARGELY CAPPED THROUGH PEAK HEATING AS H85
TEMPERATURES RISE WELL INTO THE UPPER TEENS SUPPORTING HIGHS
APPROACHING 90F. HOWEVER, SLIGHTLY WEAKER CAPPING/BETTER FORCING
ACROSS THE NORTH WARRANT AT LEAST A HIGH CHC POP FROM THE SAGINAW
VALLEY INTO THE THUMB, INCREASING TO LIKELY BY LATE THIS AFTN. THIS
ACTIVITY WILL CARRY AT LEAST A LOW END SEVERE RISK 18-00Z NORTH OF
THE I-69 CORRIDOR AS IT WILL RESIDE ALONG THE EASTERN PERIPHERY MORE
STRONGLY SHEARED SWLY FLOW AND AS SURFACE TDS RISE INTO THE MID AND
UPPER 60S SUPPORTING MODERATE DESTABILIZATION. LATEST HRRR RUNS HAVE
A DEPICTION SIMILAR TO EXPECTATIONS, PARTICULARLY WRT TO EXPECTED
SOUTHWARD EXTENT. MEANWHILE 4KM SPC RUN APPEARS ENTIRELY TOO
GENEROUS WITH CONVECTIVE COVERAGE/EVOLUTION WITHIN STRONGLY CAPPED
AREAS.
SECOND AND POTENTIALLY GREATER SEVERE THREAT MAY EXIST TONIGHT,
LARGELY CONDITIONAL ON EXTENT OF PRECEDING AFTERNOON CONVECTION AND
QUALITY OF RECOVERY. DEVELOPING STRONG SWLY FLOW IN ADVANCE OF
PRIMARY TROUGH AXIS WILL CERTAINLY GIVE THE EXPECTED GENESIS AREA
OVER NORTHERN LOWER OR CENTRAL MI A DECENT SHOT AT RECOVERY BY 00Z.
BETWEEN 00-06Z, STRONG HEIGHT FALLS WILL SPREAD ACROSS THE GREAT
LAKES ELICITING A STRONG LLJ RESPONSE AND IMPRESSIVE MEAN WIND
THROUGH THE LOWER ATMOSPHERE. ASSUMING THE ABSENCE OF STABILIZING
EFFECTS OF EARLIER ACTIVITY, CONVECTIVE INITIATION ALONG THE
INTENSIFYING SURFACE TROUGH WOULD HAVE POTENTIAL TO GROW UPSCALE AND
PROPAGATE INTO AN ENVIRONMENT CHARACTERIZED BY 0-1KM BULK SHEAR
AROUND 40KTS, H7-H5 LAPSE RATES IN EXCESS OF 7.5C/KM, AND 0-1KM
MLCAPE OF 1500 TO 2000 J/KG. THREAT WOULD THEN DIMINISH FROM TOWARD
THE FAR SOUTHEAST AS CONVECTION ENCOUNTERS COMBINATION OF
INCREASINGLY CAPPED MID-LEVELS AND NOCTURNAL STABILIZATION.
LONG TERM...
UPPER LEVEL TROUGH AXIS (EXTENDING FROM LARGE UPPER LEVEL LOW
CENTERED OVER NORTHERN ONTARIO) WILL BE IN PLACE ON MONDAY OVER THE
CENTRAL GREAT LAKES...WITH COLD 500 MB TEMPS AROUND -14 C. THE MAIN
SURFACE COLD FRONT SHOULD CLEAR SOUTHERN MICHIGAN SHORTLY AFTER
12Z...AND SOUTHEAST MICHIGAN WILL BEGIN TO DRY OUT WITH SLOWLY
FALLING DEW PTS. HOWEVER...THERE STILL COULD BE JUST ENOUGH RESIDUAL
LOW LEVEL MOISTURE AROUND TO GENERATE SUFFICIENT INSTABILITY TO POP
ISOLATED-SCATTERED SHOWERS AND MAYBE A THUNDERSTORM...AS THERE IS
ALSO A SECONDARILY COLD FRONT WHICH LOOKS TO BE DROPPING SOUTH FROM
NORTHERN LOWER MICHIGAN...PROVIDING THE BETTER FOCUS. 850 MB TEMPS
STILL IN THE LOWER TEENS ON MONDAY...ALLOWING FOR MAXES AROUND 80
DEGREES...WILL FALL INTO THE UPPER SINGLE NUMBERS TO AROUND 10 C BY
TUESDAY...WHICH SHOULD RESULT IN MAXES HOLDING IN THE MID/UPPER 70S.
A SPOKE OF UPPER LEVEL ENERGY IS FORECASTED TO SWING THROUGH
NORTHERN LOWER MICHIGAN DURING TUESDAY..COUPLED WITH THE DAYTIME
INSTABILITY COULD TOUCH OF A FEW SHOWERS NORTH OF I-69...OTHERWISE
UPPER LEVEL NORTHWEST CONFLUENT FLOW/GENERAL SUBSIDENCE REGIME LOOKS
TO PERSIST AT LEAST INTO WEDNESDAY...SUPPORTING SLOWLY STRENGTHENING
HIGH PRESSURE OVER LOWER MICHIGAN...PROVIDING FAVORABLE RADIATING
NIGHTTIME CONDITIONS ALLOWING MINS TO FALL INTO THE LOW/MID
50S...WITH HIGHS STILL STUCK IN THE 70S FOR WEDNESDAY.
MARINE...
SOUTHWEST WINDS WILL BE INCREASING TODAY AHEAD OF A COLD
FRONT...WITH 25 KNOT GUSTS EXPECTED ACROSS ALL NEARSHORE
WATERS...AND SMALL CRAFT ADVISORIES WILL CONTINUE. COLD FRONT
ARRIVING TONIGHT LOOKS TO TRIGGER THUNDERSTORMS...WHICH COULD BE
SEVERE...PRODUCING WINDS OF 50 KNOTS. WINDS WILL TURN WEST AND THEN
NORTHWEST BEHIND THE FRONT DURING MONDAY. WIND SPEEDS MONDAY LOOK TO
BE GREATEST OVER NORTHERN LAKE HURON...WHERE THEY WILL REACH BETWEEN
15 TO 25 KNOTS MONDAY NIGHT THROUGH TUESDAY NIGHT AS COOLER AIR
SETTLES OVER THE CENTRAL GREAT LAKES REGION. THERE WILL BE A CHANCE
OF SHOWERS AND ISOLATED THUNDERSTORMS OVER LAKE HURON DURING THIS
TIME FRAME AS WELL.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT FROM NOON EDT TODAY THROUGH THIS EVENING
FOR MIZ049.
LAKE HURON...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LHZ421-422-441>443.
LAKE ST CLAIR...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 4 AM EDT MONDAY FOR
LEZ444.
&&
$$
AVIATION.....JVC
UPDATE.......JVC
SHORT TERM...JVC
LONG TERM....SF
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
623 AM CDT SUN AUG 2 2015
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 455 AM CDT SUN AUG 2 2015
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING OVER SOUTH CENTRAL
IOWA IN AN AREA OF LOW LEVEL MOISTURE CONVERGENCE ON THE NOSE OF A
30KT LOW LEVEL JET. RAP SHOWS THAT THIS LOW LEVEL CONVERGENCE WILL
MOVE ACROSS THE NORTHERN PART OF THE CWA THIS MORNING. WILL KEEP
ISOLATED THUNDERSTORMS GOING OVER THIS AREA THROUGH AT LEAST THE
MORNING HOURS.
WENT WITH A BLEND OF THE MOS GUIDANCE FOR HIGHS TODAY WHICH IS
SUPPORTED BY MIXING DOWN THE 850MB TEMPERATURES.
BRITT
.LONG TERM: (TONIGHT THROUGH SATURDAY)
ISSUED AT 455 AM CDT SUN AUG 2 2015
(TONIGHT THROUGH TUESDAY)
COLD FRONT WILL MOVE DOWN INTO THE AREA TONIGHT AHEAD OF A WEAK
SHORTWAVE IN NORTHWESTERLY FLOW ALOFT. STILL EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP IN THE WEAK MOISTURE CONVERGENCE ALONG
THE COLD FRONT IN AREAS ALONG AND NORTH OF I-70. ISOLATED
THUNDERSTORMS WILL CONTINUE INTO MONDAY OVER THE SOUTHERN HALF OF
THE CWA AS THE COLD FRONT SHIFTS TO THE SOUTH. CHANCES FOR STORMS
WILL INCREASE MONDAY NIGHT INTO TUESDAY NIGHT AS THE FRONT STALLS
OVER THE AREA AS STRONGER SHORTWAVE TROUGH MOVES ACROSS THE AREA.
(WEDNESDAY THROUGH SATURDAY)
THE CHANCE OF THUNDERSTORMS WILL CONTINUE OVER THE AREA THROUGH
FRIDAY AS THE FRONT WILL REMAINED STALLED MISSOURI AND ILLINOIS.
BOTH THE ECMWF AND GFS ARE SHOWING A SERIES OF SHORTWAVES MOVING
OVER THE STALLED FRONT DURING THIS PERIOD. HIGH PRESSURE WILL
FINALLY MOVE INTO THE AREA BY SATURDAY PROVIDING A DRY DAY. WENT
WITH BELOW TEMPERATURES BECAUSE OF EXPECTED CLOUDS AND RAIN CHANCES.
BRITT
&&
.AVIATION: (FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 616 AM CDT SUN AUG 2 2015
TSRA OVER N CENTRAL MO ARE EXPECTED TO CONTINUE MOVING SEWD. THESE
STORMS ARE NOT CURRENTLY ANTICIPATED TO IMPACT UIN...BUT CAN NOT
BE RULED OUT AND WILL BE IN THE REGION. OTHERWISE, TSRA MAY ALSO
IMPACT UIN THIS EVENING AS A CDFNT APPROACHES THE REGION.
HOWEVER...TSRA SHUD DISSIPATE AS THEY APPROACH THE UIN REGION AND
WILL THEREFORE KEEP OUT OF TAF ATTM. OTHERWISE, WINDS WILL BECOME
SWLY THIS MORNING AND WLY AS THE FNT APPROACHES.
LATEST MODEL GUIDANCE SUGGESTS ISOD TO SCT TSRA WILL BE POSSIBLE
THIS AFTERNOON INTO EARLY EVENING ACROSS PORTIONS OF ERN
OZARKS...POSSIBLY AS FAR N AS THE STL/SUS/CPS REGION. CHANCES OF
DEVELOPMENT AND IMPACTING THESE TERMINALS IS TOO LOW TO MENTION IN
THE TAF ATTM.
TILLY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
501 AM CDT SUN AUG 2 2015
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 455 AM CDT SUN AUG 2 2015
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING OVER SOUTH CENTRAL
IOWA IN AN AREA OF LOW LEVEL MOISTURE CONVERGENCE ON THE NOSE OF A
30KT LOW LEVEL JET. RAP SHOWS THAT THIS LOW LEVEL CONVERGENCE WILL
MOVE ACROSS THE NORTHERN PART OF THE CWA THIS MORNING. WILL KEEP
ISOLATED THUNDERSTORMS GOING OVER THIS AREA THROUGH AT LEAST THE
MORNING HOURS.
WENT WITH A BLEND OF THE MOS GUIDANCE FOR HIGHS TODAY WHICH IS
SUPPORTED BY MIXING DOWN THE 850MB TEMPERATURES.
BRITT
.LONG TERM: (TONIGHT THROUGH SATURDAY)
ISSUED AT 455 AM CDT SUN AUG 2 2015
(TONIGHT THROUGH TUESDAY)
COLD FRONT WILL MOVE DOWN INTO THE AREA TONIGHT AHEAD OF A WEAK
SHORTWAVE IN NORTHWESTERLY FLOW ALOFT. STILL EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP IN THE WEAK MOISTURE CONVERGENCE ALONG
THE COLD FRONT IN AREAS ALONG AND NORTH OF I-70. ISOLATED
THUNDERSTORMS WILL CONTINUE INTO MONDAY OVER THE SOUTHERN HALF OF
THE CWA AS THE COLD FRONT SHIFTS TO THE SOUTH. CHANCES FOR STORMS
WILL INCREASE MONDAY NIGHT INTO TUESDAY NIGHT AS THE FRONT STALLS
OVER THE AREA AS STRONGER SHORTWAVE TROUGH MOVES ACROSS THE AREA.
(WEDNESDAY THROUGH SATURDAY)
THE CHANCE OF THUNDERSTORMS WILL CONTINUE OVER THE AREA THROUGH
FRIDAY AS THE FRONT WILL REMAINED STALLED MISSOURI AND ILLINOIS.
BOTH THE ECMWF AND GFS ARE SHOWING A SERIES OF SHORTWAVES MOVING
OVER THE STALLED FRONT DURING THIS PERIOD. HIGH PRESSURE WILL
FINALLY MOVE INTO THE AREA BY SATURDAY PROVIDING A DRY DAY. WENT
WITH BELOW TEMPERATURES BECAUSE OF EXPECTED CLOUDS AND RAIN CHANCES.
BRITT
&&
.AVIATION: (FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1119 PM CDT SAT AUG 1 2015
STILL EXPECTING DEVELOPMENT OF SHOWERS AND THUNDERSTORMS LIKELY
OVER CENTRAL IOWA IN THE PREDAWN HOURS OF SUNDAY MORNING. QUINCY
MAY BE ON SOUTHERN EDGE AND MAINTAINED A VC GROUP FOR EARLY SUNDAY
MORNING. ALTHOUGH CANNOT TOTALLY RULE OUT ACTIVITY FURTHER SOUTH
LATE SUNDAY MORNING/EARLY AFTERNOON CHANCES ARE PRETTY LOW SO KEPT
REMAINING SITES DRY. WEST/SOUTHWEST WINDS WILL PICK UP AND GUST
AT KCOU AND KUIN AS SFC PRESSURE GRADIENT TIGHTENS BUT WILL RELAX
A BIT WITH APPROACH OF NEXT COLD FRONT SUNDAY NIGHT.
SPECIFICS FOR KSTL:
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH SUNDAY NIGHT.
LIGHT/VARIABLE WINDS WILL BECOME PREDOMINANTLY SOUTHWESTERLY BY
LATE SUNDAY MORNING. NEXT COLD FRONT WILL APPROACH FROM THE
NORTHWEST LATE SUNDAY NIGHT BUT PRECIPITATION CHANCES ONCE AGAIN
DO NOT LOOK TOO HIGH WITH IT AND PASSAGE OF SAID ACTUAL FRONT
LOOKS TO BE ACTUALLY ON MONDAY MORNING.
GOSSELIN
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
621 AM CDT SUN AUG 2 2015
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
CHANCE FOR THUNDERSTORMS AND WARM TEMPERATURES TODAY...THEN OFF AND
ON STORM CHANCES THROUGH TUESDAY...ARE THE PRIMARY FORECAST CONCERNS.
SCATTERED THUNDERSTORMS POPPED UP EARLY THIS MORNING JUST AHEAD OF
MID LEVEL WAVE DROPPING SOUTHEAST THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA AS PER WATER VAPOR AND RAP ANALYSIS. THIS WAVE WILL
TRACK EAST OF OUR CWA EARLY IN THE DAYLIGHT HOURS...WITH SUBSIDENCE
BEHIND WAVE KEEPING MUCH OF THE REST OF THE MORNING DRY.
ANOTHER SHORTWAVE IN THE NORTHERN PLAINS INTO THE NORTHERN GREAT
LAKES IS FORECAST TO SWEEP SOUTHEAST LATER TODAY...WITH SURFACE
REFLECTION IN THE FORM OF A FRONT/WIND SHIFT SETTLING INTO NORTHEAST
NEBRASKA THIS AFTERNOON. SURFACE DEW POINTS NEAR OR ABOVE 70F AHEAD
OF THIS BOUNDARY ARE EXPECTED TO POOL IN EASTERN NEBRASKA AND
WESTERN IOWA DURING PEAK HEATING. CONVERGENCE ALONG BOUNDARY SHOULD
BE ENOUGH TO GET AT LEAST ISOLATED THUNDERSTORMS FIRING IN UNSTABLE
ATMOSPHERE CHARACTERIZED BY MUCAPES OVER 2500 J/KG. MEANWHILE
MODERATE MID LEVEL FLOW WILL HELP GENERATE NEAR 40KT OF BULK SHEAR
WITH VECTORS NORMAL TO SURFACE CONVERGENCE...SUGGESTING DISCRETE AND
ROTATING STORMS ARE LIKELY...SUPPORTING HAIL AND WIND POTENTIAL.
ONLY MARGINAL RISK IN SPC OUTLOOK...AND CAN NOT ARGUE GIVEN
EXPECTED SCANT COVERAGE. INITIATION LOOKS TO BE FARTHER NORTH THAN
PREVIOUS MODEL RUNS WITH LATER ARRIVAL OF FRONT...MOSTLY LIKELY
FIRING NEAR OR SOUTH OF A WAYNE TO ALBION LINE BETWEEN 3 AND 4 PM.
EXPECT ISOLATED TO SCATTERED STORMS TO PROGRESS SOUTH THROUGH THE
REST OF THE AFTERNOON INTO THE EVENING WITH FRONTAL BOUNDARY
BEFORE EXITING SOUTHEAST NEBRASKA AND SOUTHWEST AROUND MIDNIGHT
WHEN LAST OF 850 MOISTURE PLUME FINALLY DROPS SOUTH.
AHEAD OF FRONT...TEMPERATURES ARE EXPECTED WELL INTO THE 90S
ESPECIALLY IF CLOUD COVER FROM MORNING CONVECTION DISSIPATES AS
EXPECTED. WILL LIKELY SEE SOME HEAT INDICES TOPPING 100 FOR A COUPLE
OF HOURS THIS AFTERNOON.
SHOULD SEE A DRY PERIOD AFTER MIDNIGHT TONIGHT...BUT LOWERING
PRESSURES IN THE HIGH PLAINS WILL DRAW 850 MOISTURE BACK NORTH
RATHER QUICKLY BY LATER MONDAY MORNING AS NORTHWEST MID LEVEL FLOW
CONTINUES. WILL KEEP OUR SMALL POPS FOR OUR WESTERN CWA DURING THAT
TIME PERIOD...WITH CHANCES/COVERAGE GRADUALLY INCREASING MONDAY
AFTERNOON...BUT ESPECIALLY OVERNIGHT AND TUESDAY AS MAGNITUDE OF
MOISTURE RETURN INCREASES. WILL MAINTAIN 30 TO 50 PERCENT STORM
CHANCES DURING THE DAY TUESDAY. SEVERE THREAT SHOULD BE MINIMAL THEN
AS INSTABILITY REMAINS WEAK DUE TO MUCH COOLER SURFACE
TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
UNSETTLED WEATHER PATTERN WITH OCCASIONAL RAIN/STORM CHANCES WILL
CONTINUE THROUGH MUCH OF THE REST OF THE WEEK. MID LEVEL RIDGE IS
FORECAST TO REMAIN FROM TEXAS WEST TO THE SOUTHWESTERN STATES AT
LEAST THROUGH THURSDAY...KEEPING STORM TRACK ROLLING FROM THE
CENTRAL/NORTHERN ROCKIES ACROSS THE PLAINS. SEVERAL SHORTWAVES COULD
TRIGGER CONVECTION AT JUST ABOUT ANY TIME...WITH MORE POTENT WAVES
MOVING THROUGH OUR AREA WEDNESDAY DURING THE DAY AND THURSDAY
NIGHT AS PER ECMWF/GFS. WE SHOULD REMAIN ON THE COOL SIDE OF
SURFACE FRONTAL SYSTEM...SO INSTABILITY PROGS SUGGEST SEVERE
CHANCE WILL BE MINIMAL OVERALL WITH TEMPERATURES REMAINING IN THE
70S AND 80S MUCH OF THE WEEK.
&&
.AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 614 AM CDT SUN AUG 2 2015
CONDITIONS SHOULD REMAIN VFR THROUGHOUT THE MAJORITY OF THE
PERIOD. WINDS WILL GRADUALLY VEER TO THE NORTH TODAY AS A WEAK
COLD FRONT MOVES THROUGH THE REGION. A FEW STORMS COULD FIRE ALONG
THE BOUNDARY THIS EVENING AND TONIGHT. HOWEVER CONFIDENCE IN
EXACT TIMING AND LOCATION OF STORMS REMAINS LOW AT THIS TIME...SO
OPTED TO CONTINUE TO LEAVE PRECIP OUT OF THIS ISSUANCE.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...KG
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
949 AM EDT SUN AUG 2 2015
.SYNOPSIS...
A STATIONARY FRONT LINGERING ALONG THE COAST OF THE SOUTHEAST
STATES WILL DISSIPATE MONDAY. THE NEXT FRONT WILL AFFECT THE AREA
LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 945 AM SUNDAY...SOMEWHAT DRIER AIR ACROSS THE REGION THIS
MORNING AS PRECIPITABLE WATER VALUES HAVE DROP TO 1.29 INCHES WITH
DEWPOINTS IN THE UPPER 60S INLAND. WHILE MOST AREAS WILL REMAIN
DRY...THE HIGH-RESOLUTION HRRR AND ENSEMBLE WRF FROM NCAR SHOWING
SOME ISOLATED SHOWERS JUST INLAND ALONG THE SEA BREEZE DURING THE
MID-AFTERNOON HOURS. COVERAGE WILL BE VERY LIMITED AND WILL
CONTINUE WITH JUST SLIGHT CHANCE POPS. QUITE WARM INLAND WITH
PLENTY OF SUNSHINE PUSHING TEMPERATURES WELL INTO THE 90S WITH
UPPER 80S COASTAL AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS OF 3 AM SUN...BOTH MODELS INCREASE MOISTURE FROM THE SOUTH IN
RESPONSE TO BROAD UPPER TROF ALONG EASTERN SEABOARD SHARPENING UP.
WILL NUDGE POPS A BIT FURTHER NORTH AND INCREASE TO CHANCE SOUTH
OF A LINE FROM OREGON INLET TO MOREHEAD CITY.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 3 AM SUN...GFS/ECMWF TRENDING A BIT WETTER COAST MON INTO
MON NIGHT AS MOISTURE INCREASES AHEAD OF WEAK LOW LIFTING NE ALONG
REMNANT FRONTAL BOUNDARY. FOR NOW KEPT POPS IN CHC RANGE CST BUT
IF CURRENT MDL TRENDS CONT THEY MAY NEED TO BE INCREASED IN LATER
FCSTS. DEEP INLAND LOOKS MAINLY DRY AS BEST MOISTURE STAYS ALONG
THE CST. HIGHS MON LOWER 90S INLAND TO 80S CST WITH 70S AREAS WIDE
MON NIGHT.
MAIN STORY FOR THE TUE AND WED WILL BE THE HEAT AS TYPICAL
SUMMERTIME PATTERN RE-DEVELOPS WITH HIGH PRESSURE OFFSHORE AND
STRENGTHENING TROUGH INLAND. HEIGHTS BUILD THROUGH MID WEEK...WITH
LOW LEVEL THICKNESS VALUES AND 850MB TEMPS SUPPORTING HIGHS IN THE
UPPER 80S/LOW 90S ALONG THE COAST...AND MID 90S/POSSIBLY A FEW
UPPER 90S INLAND. FOR NOW FCST DEWPTS KEEP APPARENT TEMPS BELOW
105 BUT WILL BE CLOSE TO HEAT ADVRY. MAINLY SLIGHT CHC POPS TUE
AND WED WITH BEST CHC CST EARLY MORN AND INLAND DURING AFTN AND
EVENING.
CHANCE OF SHRA AND TSRA INCREASE LATE WEEK AS UPR TRF DEVELOPS TO
THE W WITH WEAK COLD FRONT APPROACHING FROM THE NW THU AND STALLING
NEAR THE AREA FRI INTO SAT. HAVE CHC POPS THRU THE PERIOD. WILL
REMAIN MUGGY HOWEVER TEMPS WONT BE QUITE A S HOT WITH MAINLY UPR 80S
AND LOWER 90S.
&&
.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
SHORT TERM /THROUGH TONIGHT/
AS OF 7 AM SUN...THE MIXTURE OF CIGS/VSBYS WILL BECOME ALL VFR IN
THE NEXT COUPLE OF HOURS AFTER SUNRISE AND ATMOSPHERIC MIXING
BEGINS. OTHERWISE...MOSTLY VFR THROUGH THE PERIOD. LIGHT
SOUTHEAST WINDS AROUND 5 KNOTS THIS AFTERNOON VEER TO SOUTH
TONIGHT. ISOLATED CONVECTION POSSIBLE AT TERMINALS EWN AND
OAJ...DRY ELSEWHERE. PATCHY IFR/MVFR FOG POSSIBLE AGAIN IN
PREDAWN HOURS MONDAY.
LONG TERM /MON THROUGH THURSDAY/...
AS OF 3 AM SUN...DECENT CVRG OF SHRA/TSRA NEAR CST MON INTO MON
NIGHT BUT BEST BET FOR REDUCED CIGS/VSBYS WILL BE MAINLY E OF
TERMINALS ESPCLY ISO/PGV WITH POSS SOME MVFR OAJ/EWN. MAINLY VFR
TUE AND WED WITH LIMITED PRECIP AND LOW LVL SW FLOW LIMITING
FOG/ST THREAT. COULD SEE BETTER CVRG OF SHRA AND TSRA THU AHEAD OF
NEXT FRONT WITH BRIEF SUB VFR POSS MAINLY IN THE AFTN.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 950 AM SUNDAY...LIGHT W/NW WINDS ON ALL THE WATERS THIS
MORNING WITH ONLY DIAMOND BUOY GUSTING ABOVE 10 KNOTS. SEAS ARE 1
TO 3 FEET...WITH SOME LONG PERIOD SWELL OVER NORTHERN AREAS. WINDS
SHOULD GRADUALLY BECOME MORE SOUTHERLY BY LATE TODAY.
LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 3 AM SUN...SSW WINDS WILL INCREASE MON AS WEAK LOW LIFTS NE
ALONG FRONT/TRF INLAND TIGHTENING GRDNT. WINDS SHLD REACH 15 TO 20
KTS MOST WTRS MON AFTN WITH SEAS BUILDING TO 4 TO 6 FEET HIGHEST
OUTER CNTRL AND SRN WTRS. SSW WINDS THEN EXPECTED AT 10 TO 20 KTS
REST OF THE FCST PERIOD AS TRF CONTS INLAND WITH HIGH OFFSHORE.
THESE WINDS WILL KEEP SEAS ELEVATED ESPCLY OUTER WTRS FROM HAT S
WHERE WILL BE MAINLY 5 TO 6 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CTC
SHORT TERM...HSA
LONG TERM...RF
AVIATION...RF/HSA
MARINE...RF/CTC
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1059 AM EDT SUN AUG 2 2015
.SYNOPSIS...
DRY HIGH PRESSURE WILL REMAIN IN PLACE ACROSS THE AREA THROUGH
MONDAY. LOW LEVEL MOISTURE WILL GRADUALLY RETURN THROUGH THE WEEK AS
ANOTHER COLD FRONT APPROACHES FROM THE NORTH THEN MOVES INTO THE
AREA AND STALLS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 AM EDT SUNDAY...DEWPOINTS ARE RUNNING A BIT LOWER THAN
FORECAST SO HAVE MADE SOME ADJUSTMENTS ACCORDINGLY. OTHER GRIDS IN
GOOD SHAPE FOR THE MOST PART. HRRR AND OTHER HIRES GUIDANCE DO STILL
WANT TO DEVELOP SOME CONVECTION OVER THE MOUNTAINS THIS AFTERNOON
DESPITE THE DRY DEWPOINTS...BUT ENOUGH LAPSE RATE ALOFT FOR SOME
MINIMAL CAPE VALUES...SO HAVE KEPT THE SLIGHT CHANCE POPS FOR THIS
AFTERNOON.
1045 UTC UPDATED...SKY COVER HAS BEEN UPDATED TO ACCOUNT FOR CIRRUS
CROSSING THE INTERSTATE 77 CORRIDOR AND MOVING INTO SW SN AND NE GA.
WINDS WERE UPDATED FROM THE LATEST NAM GUIDANCE.
AT 230 AM EDT SUNDAY...AN UPPER RIDGE WILL REMAIN OVER THE WESTERN
USA TODAY AND TONIGHT...WHILE A TROUGH PERSISTS OVER THE EAST.
WEAK...CHANNELED SHORTWAVE ENERGY WILL MOVE THROUGH BASE OF THE
TROUGH OVER VA TODAY. AT THE SURFACE...A STATIONARY FRONT WILL
REMAIN NEAR THE COASTS OF NC...SC AND GA. THE BULK OF MOISTURE
ASSOCIATED WITH THIS FEATURE WILL REMAIN SOUTHEAST OF OUR AREA...AS
WILL ASSOCIATED PRECIPITATION. MOISTURE IS EXPECTED TO INCREASE OVER
OUR AREA HOWEVER...AND FORECAST MODEL SOUNDINGS WILL BE SUPPORTIVE
OF CONVECTION THIS AFTERNOON AND EVENING IN THE MOUNTAINS.
TEMPERATURES WILL SLIGHTLY ABOVE NORMAL.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 205 AM SUNDAY...EXPECT ANOTHER QUITE DAY MONDAY BEFORE A
PATTERN CHANGE AND A RETURN THE MORE TYPICAL DIURNAL THUNDERSTORM
REGIME. AN UPPER TROF WILL BE OVER THE ERN US WITH DRY HIGH
PRESSURE IN PLACE AT THE SFC. EXPECT THE DEWPOINTS TO MIX OUT ONCE
AGAIN INTO THE 50S MOST PLACES...KEEPING INSTABILITY AT A MINIMUM.
THE GUIDANCE SHOWS A LOW PRESSURE SYSTEM FORMING OVER THE GULF AND
MOVING NE NEAR THE ATLANTIC COAST ALONG AN OLD FRONTAL BOUNDARY.
HOWEVER...MOST MDLS KEEP THE LOW SOUTH AND EAST OF THE AREA WITH
MINIMAL EFFECT OVER THE CWFA. THEREFORE...NO SIGNIFICANT CONVECTION
IS EXPECTED. TEMPERATURES WILL BE WELL ABOVE NORMAL.
THE UPPER TROF BEGINS TO LIFT TUE WITH A WLY FLOW DEVELOPING. AT THE
SFC...A WEAK FRONTAL SYSTEM SAGS INTO THE AREA FROM THE NORTH. A
MOIST LOW LEVEL FLOW RETURNS BRINGING INCREASE LOW LEVEL MOISTURE.
DEWPOINTS WILL MIX OUT...BUT ONLY TO AROUND 60. THIS WILL BRING AN
INCREASE IN INSTABILITY AND POTENTIAL FOR AFTERNOON CONVECTION.
STILL...COVERAGE APPEARS TO BE LIMITED TO ISOLATED...AND MAINLY OVER
NC. TEMPS WILL RISE A COUPLE OF DEGREES FROM MON.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 320 AM SUNDAY...THE PATTERN CHANGE IS FULLY UNDERWAY AT THE
BEGINNING OF THE MEDIUM RANGE. ZONAL FLOW ALOFT BRINGS A SERIES OF
SHORTWAVES ACROSS THE AREA THRU THU. STRONGER SHORT WAVES MOVE IN
BEGINNING FRI BRINGING A RETURN TO THE UPPER TROF TO THE EASTERN
CONUS. ANOTHER SHORTWAVE MOVES THRU ON SAT REINFORCING THE TROF. AT
THE SFC...A WEAK COLD FRONT SAGS SOUTH AND STALLS ACROSS THE AREA.
THE SHORTWAVES HELP DEVELOP A SERIES OF LOW PRESSURE CENTERS WHICH
THEN MOVE ALONG THE FRONT AND ACROSS THE AREA THRU FRI. THIS WILL
BRING INCREASING CHANCES OF MAINLY DIURNAL CONVECTION. THAT SAID...
CONVECTION COULD LINGER THRU THE NITE AS THE CWFA WILL BE IN THE
PATH OF ANY POTENTIAL MCS ACTIVITY. A STRONGER LOW PRESSURE CENTER
DEVELOPS ON SAT AND MOVES EAST OF THE AREA POSSIBLY DRAGGING THE
FRONT SOUTH OF THE AREA. HOWEVER...THE MOIST UNSTABLE AIR MASS WILL
LINGER...KEEPING THE CHC OF CONVECTION IN PLACE...ALTHOUGH WITH A
LOWER RESULTING POP. TEMPS SHOW A SLOW BUT STEADY COOLING TREND THRU
THE PERIOD...ENDING UP NEAR NORMAL BY SAT.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
AT KCLT...VFR. FEW TO OCCASIONALLY SCT CU GENERALLY 8-9KFT LATE THIS
MORNING AND WILL LIKELY LOWER SOME AS MIXING INCREASES...BUT
COVERAGE IS GENERALLY NOT EXPECTED TO BE SUFFICIENT FOR A CIG.
INSTABILITY WILL BE TOO LIMITED FOR CONVECTION. LIGHT WINDS WILL BE
FROM THE NE TODAY....VEERING SE TONIGHT. SOME GUIDANCE IS LEANING
TOWARD DAYBREAK FOG MONDAY MORNING AT SURROUNDING SITES...BUT OTHER
GUIDANCE IS LESS PESSIMISTIC.
ELSEWHERE...VFR. SO FAR MOUNTAIN FOG HAS BEEN LIMITED TO VALLEYS
WELL SW OF KAVL. HIGH VFR CIGS ARE POSSIBLE EARLY TODAY AS CIRRUS
MOVES OVERHEAD. LOW VFR CIGS LATER TODAY WILL BE POSSIBLE IN THE NC
MOUNTAINS WHERE CONVECTION WILL COULD OCCUR IN BETTER INSTABILITY.
LIGHT WINDS WILL BE FROM THE NE MORNING...EXCEPT AT KAVL WHERE THEY
WILL VEER FROM NW TO SE TODAY AND RETURN TO NW TONIGHT...AND KHKY
WHERE THEY BACK FROM NE TO N TONIGHT. GUIDANCE IS BECOMING MORE
SUPPORTIVE OF DAYBREAK FOG ON MONDAY...BUT THE BEST BET IS INITIALLY
IN MOUNTAIN VALLEYS WHERE COOL AIR WILL POOL.
OUTLOOK...GRADUALLY INCREASING PRECIPITATION/RESTRICTION CHANCES
THROUGH MID WEEK AS MOIST SOUTHERLY FLOW RETURNS.
CONFIDENCE TABLE...
15-21Z 21-03Z 03-09Z 09-12Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% MED 66%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 94%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 94%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY
EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS
ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...RWH
NEAR TERM...TDP
SHORT TERM...RWH
LONG TERM...RWH
AVIATION...JAT/TDP
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
455 AM MDT SUN AUG 2 2015
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 300 AM MDT SUN AUG 2 2015
TODAY...FLOW ALOFT REMAINS NORTHWEST. LOOKS LIKE THE NAM PROJECTS A
LOW LEVEL BOUNDARY TO SET UP THIS AFTERNOON ALONG THE WYOMING AND
COLORADO STATE LINE WITH A NICE 850/700 MB THETA-E RIDGE AXIS OVER
NORTHERN COLORADO. THUS...AS NAM DEPICTS...EXPECT ISOLATED TO
SCATTERED THUNDERSTORMS TO DEVELOP ALONG AND NEAR THE COLORADO STATE
LINE...THEN SLOWLY DIMINISH THIS EVENING ALONG THE LARAMIE RANGE.
TONIGHT/MONDAY...MODELS CONSISTENT IN SHOWING MORE MONSOONAL
MOISTURE BEING TAPPED INTO AND MOVING ACROSS OUR COUNTIES MONDAY
AFTERNOON...THOUGH NOW FURTHER WEST THAN PREVIOUS RUNS INDICATED.
STILL THOUGH...WITH A SHORTWAVE TROUGH ALOFT MOVING OVERHEAD AND
INCREASING LOW AND MID LEVEL MOISTURE...WILL CONTINUE OUR FORECAST
WITH ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ALONG
AND WEST OF INTERSTATE 25...WITH LESSER ACTIVITY FURTHER EAST.
MONDAY NIGHT/TUESDAY/TUESDAY NIGHT...SHORTWAVE TROUGH ALOFT MOVES
SLOWLY EASTWARD ACROSS OUR NORTHERN COUNTIES...AND WITH PLENTY OF
LOW AND MID LEVEL MOISTURE...WILL SEE SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS OUR NORTHERN COUNTIES...LESS ACTIVITY FURTHER
SOUTH WITH DRIER AIRMASS AND NEGATIVE THETA-E ADVECTION.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 300 AM MDT SUN AUG 2 2015
MONSOONAL MOISTURE TO REMAIN OVER THE AREA THROUGH AT LEAST
THURSDAY. DEPENDING ON WHICH MEDIUM RANGE GUIDANCE USED...IT COULD
BE LONGER. FORECAST BASED OFF THE MORE MOIST ECMWF THIS FORECAST
CYCLE.
STARTING OFF WEDNESDAY...WE ARE LOOKING AT THE SEMI-PERMANENT
THATS BEEN IN THE AREA TO LAY ALONG THE NEBRASKA
PANHANDLE...MAYBE SLIGHTLY FURTHER EAST. GFS SHOWING THE BOUNDARY
FURTHER EAST AND THUS THE ENTIRE CWFA DRY. ECMWF ON THE OTHER HAND
HAS THE BOUNDARY REMAINING ALONG THE EAST SLOPES OF THE LARAMIE
RANGE...WITH NORTHEAST UPSLOPE FLOW ACROSS THE PANHANDLE. THIS
WOULD GIVE MOST LOCATIONS ALONG AND EAST OF THE LARAMIE RANGE WITH
AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS WEDNESDAY AFTERNOON.
THURSDAY AFTERNOON...A FAIRLY STRONG SHORTWAVE TRACKS ACROSS
NORTHERN WYOMING INTO SOUTH DAKOTA. STRONG SOUTH TO SOUTHEASTERLY
850MB WINDS IN THE PANHANDLE AND A 70KT 250MB JET COULD BE SETTING
US UP FOR ANOTHER ROUND OF SEVERE THUNDERSTORMS AT LEAST FOR THE
SOUTHERN HALF OF THE PANHANDLE AS WELL AS EASTERN LARAMIE
COUNTY...UP INTO GOSHEN COUNTY. SHOWERS AND THUNDERSTORMS LOOK TO
PERSIST INTO THE LATE EVENING HOURS THURSDAY.
AFTER A DRY FRIDAY WITH A TRANSITORY RIDGE MOVING THROUGH THE
CWFA...SATURDAY LOOKS TO BE A REPEAT OF THURSDAY AS ANOTHER
SHORTWAVE MOVES INTO THE AREA FROM THE SOUTHWEST. SHOULD SEE AT
LEAST SLIGHT CHANCE POPS FOR MUCH OF THE AREA WITH BEST CHANCES
ALONG THE WYOMING COLORADO STATE LINE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 450 AM MDT SUN AUG 2 2015
LOOKS LIKE A REPEAT IN THE FORECAST FOR SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE AIRPORTS AS WAS THE CASE SATURDAY. HRRR USED
FOR TIMING OF CONVECTION...MAINLY ALONG THE I-80 CORRIDOR FROM
KSNY TO KLAR. TIMING LOOKS TO BE FROM 20Z THROUGH 01Z.
&&
.FIRE WEATHER...
ISSUED AT 145 AM MDT SUN AUG 2 2015
HUMIDITIES INCREASING THE NEXT FEW DAYS AS LOW AND
MID LEVEL MOISTURE INCREASES ALONG WITH INCREASING CHANCES FOR LATE
DAY SHOWERS AND THUNDERSTORMS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN
AREA FORECAST DISCUSSION
NWS TUCSON AZ
955 AM MST SUN AUG 2 2015
.SYNOPSIS...A DRYING TREND WILL LEAD TO LESS THUNDERSTORM ACTIVITY
TODAY AND MONDAY...WITH THUNDERSTORMS CONFINED TO MAINLY NEAR THE
NEW MEXICO BORDER TUESDAY. PRECIPITATION CHANCES WILL THEN INCREASE
AROUND THURSDAY FOLLOWED BY A CHANCE OF THUNDERSTORMS ACROSS MUCH OF
SOUTHEAST ARIZONA FRIDAY AND SATURDAY. EXPECT ABOVE NORMAL DAYTIME
TEMPERATURES THIS WEEK.
&&
.DISCUSSION...IR/VISIBLE SATELLITE IMAGERY INDICATED MOSTLY CLOUDY
SKIES NEAR THE NEW MEXICO BORDER AT THIS TIME...WHILE SUNNY SKIES
WERE THE RULE WEST OF TUCSON. WATER VAPOR IMAGERY DEPICTED THE
DEEPER MOISTURE TO BE ACROSS FAR ERN SECTIONS. MEANWHILE...A
A DISTINCTLY DRIER MID/UPPER LEVEL REGIME WAS DEPICTED VIA WATER
VAPOR IMAGERY FROM TUCSON WWD INTO WRN PIMA COUNTY. 02/12Z KTWC
SOUNDING ALSO DEPICTED A MARKEDLY DRIER REGIME ABOVE 400 MB VERSUS
24 HOURS AGO. HOWEVER...THE PROFILE WAS STILL QUITE MOIST...WITH
TOTAL PRECIP WATER VALUE OF 1.52 INCHES. 02/12Z UPPER AIR PLOTS
DEPICTED LIGHT TO MODERATE GENERALLY WLY FLOW ACROSS MUCH OF THIS
FORECAST AREA...AS A RIDGE AXIS EXTENDED FROM THE PERMIAN BASIN OF
WEST TEXAS SWWD TO WEST OF THE BAJA CALIFORNIA SPUR.
02/12Z NAM/GFS...02/00Z ECMWF AND VARIOUS RUC HRRR SOLUTIONS AGREE
THAT SCATTERED SHOWERS/TSTMS WILL FAVOR GREENLEE/GRAHAM/COCHISE
COUNTIES EAST OF TUCSON THIS AFTERNOON AND EARLY THIS EVENING. THERE
APPEARS TO BE ENOUGH MOISTURE TO SUPPORT AT LEAST A SLIGHT CHANCE OF
SHOWERS/TSTMS THIS AFTERNOON/EVENING FROM THE VICINITY OF NOGALES
NWD ACROSS ERN PIMA COUNTY...INCLUDING TUCSON...AND FURTHER NWD INTO
SOUTHEASTERN PINAL COUNTY. PRECIP-FREE CONDITIONS SHOULD OCCUR
ACROSS WRN PIMA COUNTY...AND MUCH OF THE TOHONO O`ODHAM NATION AND
SOUTH CENTRAL PINAL COUNTY. IF THE VARIOUS RUC HRRR SOLUTIONS BECOME
REALITY...SHOWERS/TSTMS WILL QUICKLY DISSIPATE THIS EVENING. FOR
NOW...WILL MAINTAIN A SLIGHT CHANCE OF SHOWERS/TSTMS LATE TONIGHT
ACROSS FAR ERN SECTIONS WITH DRY CONDITIONS ELSEWHERE.
HIGH TEMPS THIS AFTERNOON WILL BE QUITE CLOSE TO TEMPS ACHIEVED
SAT...OR WILL BE A FEW DEGREES WARMER DEPENDING UPON LOCATION. A
WARMING TREND WILL THEN OCCUR MON-TUE AS THE DRYING TREND CONTINUES
ACROSS THE AREA.
THERE ARE NO UPDATES NECESSARY FOR THE INHERITED OFFICIAL FORECAST.
PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL.
&&
.AVIATION...VALID THRU 03/18Z.
EXPECT SCATTERED -TSRA/-SHRA EAST AND SOUTH OF KTUS THIS AFTERNOON
AND EVENING. THERE IS A 10-20 PERCENT CHANCE OF -TSRA/-SHRA AT KTUS
THIS AFTERNOON AND EVENING...BUT THIS CHANCE IS TOO LOW TO INCLUDE
IN THE TAF. THE BULK OF ANY -TSRA/-SHRA WILL BE EAST OF THE NEW
MEXICO BORDER BY AROUND 03/06Z. HOWEVER...ISOLATED MAINLY -SHRA WILL
BE POSSIBLE EAST OF KTUS LATE TONIGHT INTO MONDAY MORNING.
OTHERWISE...WEST OF KTUS EXPECT CLEAR SKIES OR A FEW CLOUDS ABOVE
10K FT AGL THROUGH THE PERIOD. EAST AND SOUTH OF KTUS...A FEW TO
BROKEN CLOUDS MAINLY AT 7-11K FT AGL THIS AFTERNOON AND EVENING...
THEN CLOUD DECKS MOSTLY ABOVE 10K FT AGL LATE TONIGHT INTO MONDAY
MORNING. SURFACE WIND WILL GENERALLY BE LESS THAN 10 KTS. AVIATION
DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&
.FIRE WEATHER...SOUTHWEST WINDS ALOFT TODAY WILL BEGIN TO USHER
DRIER AIR INTO THE REGION. PRECIPITATION CHANCES TODAY WILL
GENERALLY BE CONFINED TO AREAS EAST OF TUCSON AND NEAR HIGH
TERRAIN...BEFORE BEING RELEGATED TO FAR SOUTHEASTERN PORTIONS OF
ARIZONA AND MOUNTAINS ON MONDAY. THE LOWEST PRECIPITATION CHANCES
WILL OCCUR ON TUESDAY. HIGH PRESSURE RETURNS TO A MORE FAVORABLE
LOCATION FOR DAILY CHANCES OF SHOWERS AND THUNDERSTORMS THURSDAY
INTO SATURDAY. OUTSIDE OF THUNDERSTORM WIND GUSTS...20-FT WINDS
WILL GENERALLY BE TERRAIN DRIVEN AND LESS THAN 15 MPH. HOWEVER SOME
AFTERNOON AND EARLY EVENING BREEZINESS IS LIKELY DUE TO DAYTIME
HEATING...ESPECIALLY THROUGH THE GILA VALLEY NEAR SAFFORD.
&&
.PREV DISCUSSION...THE DRY PUSH WILL CONTINUE IN EARNEST ON
MONDAY...AIDED BY DEEPENING SOUTHWESTERLY/WESTERLY FLOW. THIS WILL
RELEGATE THUNDERSTORMS TO NEAR THE AZ/NM BORDER AND THE WHITE
MOUNTAINS. TUESDAY MAY BE THE MOST INACTIVE DAY IN THIS FORECAST
PACKAGE...AS THE MID-LEVEL HIGH CENTER PIVOTS ALMOST DIRECTLY
OVERHEAD.
MODEL DIFFERENCES BEGIN TO INCREASE STARTING WEDNESDAY AND REVOLVE
AROUND THE DEGREE OF MOISTURE RETURN WE SEE AS THE SUBTROPICAL HIGH
BEGINS TO MIGRATE EAST INTO NM...THE GFS BEING THE QUICKEST OF THE
00Z GFS/ECMWF/CMC NWP SUITE. AT THIS TIME...HAVE OPTED TO MAINTAIN
SLIGHT CHANCE POPS SOUTH OF TUCSON...ALTHOUGH BASED ON THE TIMING OF
THE EASTWARD-MOVING HIGH CENTER...THIS MAY STILL BE OVERDONE.
FOR THURSDAY THROUGH SATURDAY...PRECIPITATION CHANCES WILL
INCREASE AS WELL AS SHIFT FROM WEST-TO-EAST ACROSS THE CWA AS THE
MID-LEVEL HIGH TEMPORARILY MOVES TO A MORE TYPICAL AUGUST POSITION
ACROSS CENTRAL AND NORTHERN NM. ALAS...THIS INCREASE IN CONVECTIVE
COVERAGE MAY BE SHORT-LIVED AS ANOTHER TROUGH AXIS IS POISED TO
SWING INTO THE THE GREAT BASIN.
&&
.TWC WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
FRANCIS
PREVIOUS DISCUSSION...CARLAW
AREA FORECAST DISCUSSION
NWS PUEBLO CO
237 PM MDT SUN AUG 2 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 235 PM MDT SUN AUG 2 2015
...HEAVY RAIN POSSIBLE OVER THE MOUNTAINS TONIGHT...
...ANOTHER ROUND OF STORMS TOMORROW...SOME ON THE STRONG SIDE...
MAIN CONCERN FOR THE SHORT TERM IS POTENTIAL FOR FLASH FLOODING OVER
THE MOUNTAINS THROUGH TONIGHT. SCT TO NMRS SHOWERS AND STORMS
HAVE ALREADY DEVELOPED THIS AFTERNOON...AND AS A STRONG SHORTWAVE
NOW MOVING THROUGH AZ AND UT CONTINUES TO TRANSLATE TO THE NE THIS
EVENING...THE THREAT FOR LOCALLY HEAVY RAINFALL WILL PERSIST.
LATEST GUIDANCE SHOWS THE ASSOCIATED UPPER LOW OVER UT MOVING INTO
NW CO BY 12-15Z MON MORNING. AM PARTICULARLY CONCERNED BY THE
LATEST HIGH RES WRF AND HRRR RUNS...WHICH BOTH SHOW A STRONG BAND
OF HEAVY PRECIP MOVING THROUGH SW-CENTRAL CO BETWEEN 03Z AND 09Z
TONIGHT. THIS WOULD COINCIDE WITH STRONGEST UPPER FORCING FROM THE
SHORT WAVE. IN COORDINATION WITH KGJT AND KABQ HAVE EXPANDED OUR
FLASH FLOOD WATCH FOR THE SAN JUANS TO INCLUDE THE REST OF THE
CONTDVD...ALONG WITH THE SANGRE DE CRISTO RANGE...THROUGH 09Z
TONIGHT. THIS MAY HAVE TO BE EXTENDED SLIGHTLY IF THE BANDED HEAVY
PRECIP GETS A DELAYED START...BUT THERE IS STILL SOME UNCERTAINTY
ON HOW INTENSE THE PRECIP WILL BE...ESPECIALLY SINCE THE STRONGEST
FORCING WILL OCCUR DURING THE OVERNIGHT HOURS WHEN CONVECTION IS
GENERALLY LESS INTENSE. NEVERTHELESS...ANYONE PLANNING ON BEING IN
OR TRAVELING THROUGH THE MTS THIS EVE AND OVERNIGHT NEEDS TO BE
AWARE OF THE POTENTIAL FOR FLOOD-PRODUCING RAINS...WHICH COULD
LEAD TO SUDDEN SMALL STREAM RISES...FLOODED ROADWAYS...AND MUD OR
ROCK SLIDES IN THE STEEPER TERRAIN.
TOMORROW...THE UPPER WAVE WILL CONTINUE TO MOVE TO THE NE DURING THE
DAY...INTO SRN WY BY 00Z TUE. THIS WILL BRING SEVERAL MORE ROUNDS OF
CONVECTION TO THE AREA...PARTICULARLY OVER THE HIGHER TERRAIN. LOW
LEVEL MOISTURE WILL ALSO INCREASE OVER THE PLAINS. ALONG WITH
INCREASED SHEAR...THIS WILL RAISE THE THREAT OF SOME STRONG TO
POSSIBLY SVR STORMS OVER THE AREA. IT LOOKS LIKE THE GREATEST
INSTABILITY WILL BE OVER THE SERN PLAINS GENERALLY SOUTH OF HGWY 50
AND E OF I-25...AND THIS IS WHERE THE STRONGEST STORMS LIKELY WILL
BE DURING THE AFTERNOON. LOWER TEMPS ALOFT ALONG WITH INCREASED LLVL
MOISTURE AND PRECIP/CLOUDS WILL HOLD HIGH TEMPS A GOOD 5-10 DEGREES
BELOW THE HIGH TEMPS FROM TODAY...SO WILL SEE MAINLY TEMPS IN THE
70S AND 80S MON AFTERNOON. ROSE
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 235 PM MDT SUN AUG 2 2015
MON NIGHT...AS AN UPR DISTURBANCE MOVES NORTHEASTWARD OUT OF SERN
CO AND AN UPR TROF MOVES NORTHWARD INTO WY...THE ISOLD TO SCT PCPN
ACRS THE FORECAST SHOULD COME TO AN END AROUND MIDNIGHT. ON TUE AN
UPR RIDGE AXIS WL LIE FROM AZ INTO THE GREAT BASIN REGION...
RESULTING IN W TO NW FLOW ALOFT OVR THE FORECAST AREA. THE LATEST
RUN OF THE NAM AND GFS SHOWS DRIER CONDITIONS FOR TUE...WITH MAINLY
JUST SOME ISOLD PCPN CHANCES. TUE NIGHT SFC HIGH PRESSURE BACKS INTO
ERN CO AND IS EXPECTED TO BRING INCREASING LOW LEVEL MSTR AND THE
POTENTIAL FOR SOME LOW CLOUDS. AS A RESULT...THE NAM PRINTS OUT THE
POTENTIAL FOR SOME LIGHT PCPN OVR THE FAR SERN PLAINS LATE TUE NIGHT
AND EARLY WED MORNING...HOWEVER WL LEAVE THE FORECAST DRY FOR NOW.
ON WED THE UPR RIDGE AXIS SHIFTS EASTWARD OVR CO WITH RELATIVELY DRY
CONDITIONS EXPECTED THRU MUCH OF THE DAY WITH MAINLY JUST SOME
ISOLD PCPN OVR AND NR THE MTN AREAS. HOWEVER A WEAK DISTURBANCE
MAY ROUND THE TOP OF THE RIDGE AND MOVE THRU ERN CO IN THE EVENING
HOURS TO HELP KICK OFF SOME CONVECTION ACRS THE PLAINS. ON THU THE
UPR RIDGE GETS FLATTENED ACRS THE FORECAST AREA AS A SHORTWAVE
TROF MOVES THRU MT WY AND NRN CO. ONLY SOME ISOLD PCPN IS EXPECTED
THU AFTERNOON...BUT THEN AS THAT DISTURBANCE MOVES OFF INTO THE
PLAINS STATES THE ECMWF IS STILL SHOWING AN MCS DEVELOPING AND
AFFECTING PORTIONS OF ERN CO BY THU EVENING.
FRI AN UPR TROF IS EXPECTED TO MOVE OVR CA...WITH AN UPR RIDGE BEING
OVR CO. MSTR STILL LOOKS TO BE SOMEWHAT LIMITED DURING THE
DAY...WITH MAYBE JUST SOME ISOLD TO SCT PCPN OVR THE FORECAST AREA.
THEN FRI NIGHT AND SAT AS THAT UPR TROF MOVES EAST-NORTHEASTWARD
INTO ID AND UT...MONSOON MSTR IS EXPECTED TO BE DRAWN NORTHWARD INTO
WESTERN CO AGAIN WHICH WL INCREASE THE CHANCES FOR PCPN...ESPECIALLY
OVR THE MTNS AND HIGH VALLEYS. AS THE UPR DISTURBANCE MOVES EASTWARD
ACRS MT AND WY SAT NIGHT...PCPN IS EXPECTED TO SPREAD ACRS THE ERN
CO PLAINS. THEN BY SUN IT LOOKS LIKE THE FORECAST AREA WL AGAIN BE
CUTOFF FROM THE MONSOON MSTR...LEADING TO DRIER CONDITIONS AGAIN.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 235 PM MDT SUN AUG 2 2015
MAIN CONCERN CONTINUES TO BE STORMS THIS AFTERNOON AND THIS EVE. AT
KCOS AND KPUB THIS THREAT WILL BE HIGHEST THROUGH AROUND
03Z...ALTHOUGH ISOLD STORMS WILL BE POSSIBLE THROUGH TONIGHT. AT
KALS...SEVERAL ROUNDS OF MODT TO HEAVY PRECIP WILL BE POSSIBLE
THROUGH TONIGHT. COULD SEE SEVERAL ROUNDS OF MVFR TO OCCASIONALLY
IFR DEVELOP FOR THE SAN LUIS VALLEY DUE TO LOW CIGS AND/OR VIS. AS
AN UPPER LEVEL DISTURBANCE CONTINUES TO MOVE NEWD FROM UT INTO NW CO
AND SW WY...THIS WILL KEEP THE THREAT OF PRECIP AND LOW CIGS GOING
THROUGH MON MORNING FOR MUCH OF SE CO. STORMS COULD REDEVELOP MON
AFTERNOON BEFORE DISSIPATING FROM SW TO NE MON EVENING. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR COZ058-060-061-063-
066>068-072>075.
&&
$$
SHORT TERM...ROSE
LONG TERM...28
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1119 AM MDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1047 AM MDT SUN AUG 2 2015
UPDATED TO DELAY TIMING OF HIGHER POPS BY A FEW HOURS. STILL NOT
SEEING THE PRECIP OVER SW CO MOVE INTO OUR AREA...BUT SHOULD SEE
FAIRLY STEADY INCREASE IN PRECIP THIS AFTERNOON. LATEST HRRR AND
OTHER GUIDANCE IS SHOWING SIGNIFICANT QPF OVER THE WRN CWA THIS
EVENING. WILL CONSIDER EXPANDING THE FLOOD WATCH BASED ON TRENDS
EARLY THIS AFTERNOON. ROSE
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM MDT SUN AUG 2 2015
CURRENTLY...QUIET WEATHER HAS SPREAD ACROSS SOUTHERN COLORADO EARLY
THIS MORNING. TEMPERATURES HAVE REMAINED MILD WITH 60S OVER THE
LOWER ELEVATIONS UNDER LIGHT WINDS.
TODAY AND TONIGHT...A STRONG UPPER LEVEL DISTURBANCE UNDER A BROAD
AREA OF HIGH PRESSURE ALOFT IS FORECAST TO ROTATE NORTHWARD ACROSS
UTAH AND WESTERN COLORADO THIS AFTERNOON AND TONIGHT. ABUNDANT
MOISTURE IS IN PLACE...AND MODELS DEVELOP LOW LEVEL SOUTHEASTERLY
UPSLOPE FLOW ACROSS THE SAN LUIS VALLEY INTO THE EASTERN SAN JUANS
FOR THIS AFTERNOON. ALL WILL COMBINE TO PROVIDE THE FOCUS FOR
THUNDERSTORMS THIS AFTERNOON OVER THE SAN JUAN RANGE...NORTH INTO
THE LA GARITA MOUNTAINS. LOCALLY HEAVY RAINFALL IS EXPECTED WITH
THESE THUNDERSTORMS...AND FLASH FLOODING WILL BE OF
CONCERN...ESPECIALLY FOR THE WEST FORK COMPLEX BURN SCAR. A FLASH
FLOOD WATCH HAS BEEN ISSUED FOR THE BURN SCAR AREA FOR THIS
AFTERNOON AND EVENING.
ELSEWHERE...EXPECT WIDESPREAD SHOWERS AND THUNDERSTORMS OVER ALL THE
MOUNTAIN AREAS AND THE SAN LUIS VALLEY THIS AFTERNOON AND EVENING.
LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH STRONGER CORES ALONG
WITH LIGHTNING.
THERE IS LESS CERTAINTY OVER THE EASTERN PLAINS. MOST HIGH-RES
MODELS BRING DRIER AIR INTO THE PLAINS THIS AFTERNOON LIMITING
AFTERNOON INSTABILITY ALONG WITH THE SHOWER AND THUNDERSTORM
POTENTIAL. THAT BEING SAID...MOST HIGH-RES SOLUTIONS DO BRING
SHOWERS AND THUNDERSTORMS INTO THE PALMER DIVIDE AND RATON MESA
REGIONS THIS AFTERNOON AND HAVE THE HIGHEST POPS OVER THESE
LOCATIONS. THERE ARE A COUPLE OF SOLUTIONS...NAMELY THE ARW AND THE
NSSL WRF...WHICH DO BRING A ROUND OF SHOWERS AND THUNDERSTORMS INTO
THE I-25 CORRIDOR BY THIS EVENING...AND HAVE LOW POPS IN THIS AREA
TO ACCOUNT FOR THE UNCERTAINTY. THE FAR EASTERN PLAINS WILL MOST
LIKELY REMAIN DRY THROUGH TONIGHT.
MODELS IN GOOD AGREEMENT WITH SHOWERS AND THUNDERSTORMS DISSIPATING
ACROSS MUCH OF THE AREA AROUND MIDNIGHT. THE EXCEPTION LOOKS TO BE
ALONG THE CONTINENTAL DIVIDE WHERE INFLUENCES OF THE UPPER
DISTURBANCE OVER UTAH INTO WESTERN COLORADO WILL REMAIN FELT INTO
MONDAY MORNING. MOZLEY
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 341 AM MDT SUN AUG 2 2015
...MONSOON EARLY IN THE WEEK...DRIER FOR A COUPLE DAYS...THEN
MONSOON RETURNING BY WEEKS END...
ON MONDAY...SOUTHERN COLORADO WILL BE UNDER THE INFLUENCE OF A
SUBTROPICAL DISTURBANCE...CARRYING MONSOON MOISTURE THROUGH THE
REGION. WATER CONTENT OF THE ATMOSPHERE WILL BE HIGH WITH
THUNDERSTORM INITIATION AIDED BY LIFT FROM THE DISTURBANCE.
SO...ANOTHER ACTIVE DAY ACROSS THE REGION...WITH PRIMARY THREATS
OF LIGHTNING AND HEAVY RAIN...ALONG WITH GUSTY WINDS AND SOME
SMALL HAIL. FLASH FLOODING WILL CONTINUE TO BE A CONCERN.
TUESDAY IS NOT CURRENTLY LOOKING AS MOIST AS IT ONCE DID. MODELS
ARE INDICATING...NOW...THAT DRIER AIR FROM THE WEST WILL ALREADY
BE MAKING ITS WAY INTO THE REGION. THERE WILL LIKELY STILL BE
ENOUGH MOISTURE AROUND FOR CONVECTION THIS DAY...BUT MUCH LESS SO
THAN ON MONDAY. STILL THREATS OF LIGHTNING AND LOCALLY HEAVY RAIN
THIS DAY...BUT STARTING TO TREND TOWARD MORE OF A GUSTY WIND
THREAT AS DRIER AIR MOVES IN.
WEDNESDAY AND THURSDAY LOOK LIKE MOSTLY DRY AND WARM DAYS...AS DRY
WESTERLY FLOW PREVAILS OVER THE REGION...AND THE MONSOON GETS
SUPPRESSED WELL TO THE SOUTH. MOSTLY ISOLATED STORMS OVER THE
HIGHER TERRAIN ON THESE DAYS WITH PRIMARILY A LIGHTNING AND GUSTY
WIND THREAT. A LITTLE TRICKY THURSDAY EVENING...THOUGH...AS SOME
MODEL RUNS ARE CLIPPING THE FAR EASTERN PLAINS WITH AN MCS MOVING
THROUGH THE CENTRAL HIGH PLAINS.
ON FRIDAY AND SATURDAY...IT LOOKS LIKE WE WILL TRANSITION BACK INTO
THE MONSOON. MODELS INDICATE AN INTENSE LOW PRESSURE SYSTEM WILL
MOVE ONSHORE OVER CENTRAL CALIFORNIA LATE FRIDAY AND TRACK INTO THE
GREAT BASIN ON SATURDAY. AS THE SYSTEM MOVES INLAND...IT LOOKS LIKE
IT WILL PULL ANOTHER STRONG SURGE OF MONSOON MOISTURE NORTH INTO
COLORADO. THE MOISTURE STARTS TO SHOW UP ON FRIDAY...BUT REALLY
BLANKETS THE REGION ON SATURDAY. WITH THE RETURN OF THE MONSOON
MOISTURE PLUME...THE THREAT OF HEAVY RAIN AND FLASH FLOODING WILL
RETURN...ALONG WITH CONTINUED THREATS OF LIGHTNING AND GUSTY
WINDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1114 AM MDT SUN AUG 2 2015
MAIN AVN CONCERN TODAY IS POTENTIAL FOR HEAVY RAIN WITH TS THIS
AFTERNOON AND EVENING. SCT TO NMRS TS OVER THE CONTDVD WILL
BUILD THROUGH THIS AFTERNOON AND EVE. KALS HAS THE BEST CHANCE OF
SEEING PRECIP LATER THIS AFTERNOON THROUGH TONIGHT. COULD SEE MVFR
OR BRIEF IFR DEVELOP AFTER 21-22Z AND PERSISTING AT TIMES THROUGH
TONIGHT. DEPENDING ON EXTENT OF PRECIP COULD POTENTIALLY SEE SOME
LOCALIZED LOW CIGS MON MORNING OVER THE SAN LUIS VALLEY.
AT KCOS AND KPUB...TIMING OF STORMS WILL BE LATER AND LESS
LIKELY...AS THE MORE WIDESPREAD PRECIP REMAINS OVER THE MTS.
HOWEVER...ISOLD STORMS COULD AFFECT THE I-25 CORRIDOR THROUGH
EARLY EVE. SFC WINDS SHOULD SHIFT TO AN ERLY DIRECTION DURING
THIS TIME BEFORE DIMINISHING LATE THIS EVENING. ROSE
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR COZ067-068.
&&
$$
UPDATE...ROSE
SHORT TERM...MOZLEY
LONG TERM...LW
AVIATION...ROSE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1050 AM MDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1047 AM MDT SUN AUG 2 2015
UPDATED TO DELAY TIMING OF HIGHER POPS BY A FEW HOURS. STILL NOT
SEEING THE PRECIP OVER SW CO MOVE INTO OUR AREA...BUT SHOULD SEE
FAIRLY STEADY INCREASE IN PRECIP THIS AFTERNOON. LATEST HRRR AND
OTHER GUIDANCE IS SHOWING SIGNIFICANT QPF OVER THE WRN CWA THIS
EVENING. WILL CONSIDER EXPANDING THE FLOOD WATCH BASED ON TRENDS
EARLY THIS AFTERNOON. ROSE
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 341 AM MDT SUN AUG 2 2015
CURRENTLY...QUIET WEATHER HAS SPREAD ACROSS SOUTHERN COLORADO EARLY
THIS MORNING. TEMPERATURES HAVE REMAINED MILD WITH 60S OVER THE
LOWER ELEVATIONS UNDER LIGHT WINDS.
TODAY AND TONIGHT...A STRONG UPPER LEVEL DISTURBANCE UNDER A BROAD
AREA OF HIGH PRESSURE ALOFT IS FORECAST TO ROTATE NORTHWARD ACROSS
UTAH AND WESTERN COLORADO THIS AFTERNOON AND TONIGHT. ABUNDANT
MOISTURE IS IN PLACE...AND MODELS DEVELOP LOW LEVEL SOUTHEASTERLY
UPSLOPE FLOW ACROSS THE SAN LUIS VALLEY INTO THE EASTERN SAN JUANS
FOR THIS AFTERNOON. ALL WILL COMBINE TO PROVIDE THE FOCUS FOR
THUNDERSTORMS THIS AFTERNOON OVER THE SAN JUAN RANGE...NORTH INTO
THE LA GARITA MOUNTAINS. LOCALLY HEAVY RAINFALL IS EXPECTED WITH
THESE THUNDERSTORMS...AND FLASH FLOODING WILL BE OF
CONCERN...ESPECIALLY FOR THE WEST FORK COMPLEX BURN SCAR. A FLASH
FLOOD WATCH HAS BEEN ISSUED FOR THE BURN SCAR AREA FOR THIS
AFTERNOON AND EVENING.
ELSEWHERE...EXPECT WIDESPREAD SHOWERS AND THUNDERSTORMS OVER ALL THE
MOUNTAIN AREAS AND THE SAN LUIS VALLEY THIS AFTERNOON AND EVENING.
LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH STRONGER CORES ALONG
WITH LIGHTNING.
THERE IS LESS CERTAINTY OVER THE EASTERN PLAINS. MOST HIGH-RES
MODELS BRING DRIER AIR INTO THE PLAINS THIS AFTERNOON LIMITING
AFTERNOON INSTABILITY ALONG WITH THE SHOWER AND THUNDERSTORM
POTENTIAL. THAT BEING SAID...MOST HIGH-RES SOLUTIONS DO BRING
SHOWERS AND THUNDERSTORMS INTO THE PALMER DIVIDE AND RATON MESA
REGIONS THIS AFTERNOON AND HAVE THE HIGHEST POPS OVER THESE
LOCATIONS. THERE ARE A COUPLE OF SOLUTIONS...NAMELY THE ARW AND THE
NSSL WRF...WHICH DO BRING A ROUND OF SHOWERS AND THUNDERSTORMS INTO
THE I-25 CORRIDOR BY THIS EVENING...AND HAVE LOW POPS IN THIS AREA
TO ACCOUNT FOR THE UNCERTAINTY. THE FAR EASTERN PLAINS WILL MOST
LIKELY REMAIN DRY THROUGH TONIGHT.
MODELS IN GOOD AGREEMENT WITH SHOWERS AND THUNDERSTORMS DISSIPATING
ACROSS MUCH OF THE AREA AROUND MIDNIGHT. THE EXCEPTION LOOKS TO BE
ALONG THE CONTINENTAL DIVIDE WHERE INFLUENCES OF THE UPPER
DISTURBANCE OVER UTAH INTO WESTERN COLORADO WILL REMAIN FELT INTO
MONDAY MORNING. MOZLEY
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 341 AM MDT SUN AUG 2 2015
...MONSOON EARLY IN THE WEEK...DRIER FOR A COUPLE DAYS...THEN
MONSOON RETURNING BY WEEKS END...
ON MONDAY...SOUTHERN COLORADO WILL BE UNDER THE INFLUENCE OF A
SUBTROPICAL DISTURBANCE...CARRYING MONSOON MOISTURE THROUGH THE
REGION. WATER CONTENT OF THE ATMOSPHERE WILL BE HIGH WITH
THUNDERSTORM INITIATION AIDED BY LIFT FROM THE DISTURBANCE.
SO...ANOTHER ACTIVE DAY ACROSS THE REGION...WITH PRIMARY THREATS
OF LIGHTNING AND HEAVY RAIN...ALONG WITH GUSTY WINDS AND SOME
SMALL HAIL. FLASH FLOODING WILL CONTINUE TO BE A CONCERN.
TUESDAY IS NOT CURRENTLY LOOKING AS MOIST AS IT ONCE DID. MODELS
ARE INDICATING...NOW...THAT DRIER AIR FROM THE WEST WILL ALREADY
BE MAKING ITS WAY INTO THE REGION. THERE WILL LIKELY STILL BE
ENOUGH MOISTURE AROUND FOR CONVECTION THIS DAY...BUT MUCH LESS SO
THAN ON MONDAY. STILL THREATS OF LIGHTNING AND LOCALLY HEAVY RAIN
THIS DAY...BUT STARTING TO TREND TOWARD MORE OF A GUSTY WIND
THREAT AS DRIER AIR MOVES IN.
WEDNESDAY AND THURSDAY LOOK LIKE MOSTLY DRY AND WARM DAYS...AS DRY
WESTERLY FLOW PREVAILS OVER THE REGION...AND THE MONSOON GETS
SUPPRESSED WELL TO THE SOUTH. MOSTLY ISOLATED STORMS OVER THE
HIGHER TERRAIN ON THESE DAYS WITH PRIMARILY A LIGHTNING AND GUSTY
WIND THREAT. A LITTLE TRICKY THURSDAY EVENING...THOUGH...AS SOME
MODEL RUNS ARE CLIPPING THE FAR EASTERN PLAINS WITH AN MCS MOVING
THROUGH THE CENTRAL HIGH PLAINS.
ON FRIDAY AND SATURDAY...IT LOOKS LIKE WE WILL TRANSITION BACK INTO
THE MONSOON. MODELS INDICATE AN INTENSE LOW PRESSURE SYSTEM WILL
MOVE ONSHORE OVER CENTRAL CALIFORNIA LATE FRIDAY AND TRACK INTO THE
GREAT BASIN ON SATURDAY. AS THE SYSTEM MOVES INLAND...IT LOOKS LIKE
IT WILL PULL ANOTHER STRONG SURGE OF MONSOON MOISTURE NORTH INTO
COLORADO. THE MOISTURE STARTS TO SHOW UP ON FRIDAY...BUT REALLY
BLANKETS THE REGION ON SATURDAY. WITH THE RETURN OF THE MONSOON
MOISTURE PLUME...THE THREAT OF HEAVY RAIN AND FLASH FLOODING WILL
RETURN...ALONG WITH CONTINUED THREATS OF LIGHTNING AND GUSTY
WINDS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 341 AM MDT SUN AUG 2 2015
KALS...VFR CONDITIONS THIS MORNING. SHOWERS AND THUNDERSTORMS ARE
FORECAST TO DEVELOP ACROSS THE MOUNTAINS AND SAN LUIS VALLEY BY LATE
MORNING AND CONTINUE THROUGH THE EVENING. THEY WILL MOST LIKELY
IMPACT THE TERMINAL...ESPECIALLY AFTER 18Z. REDUCED CIGS AND VIS
ARE EXPECTED IN PASSING THUNDERSTORMS.
KCOS...VFR CONDITIONS THROUGH EARLY AFTERNOON. SHOWERS AND
THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING NEAR THE TERMINAL.
IF A THUNDERSTORMS DOES MOVE OVER THE TERMINAL...IT WILL REDUCE THE
CIGS AND VIS...OTHERWISE VFR CONDITIONS WILL PREVAIL INTO TONIGHT.
KPUB...VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS. THERE IS
A LOW PROBABILITY OF SHOWERS AND THUNDERSTORMS IN AND NEAR THE
TERMINAL THIS AFTERNOON AND EVENING...BUT CONFIDENCE IN OCCURRENCE
IS LOW AT THIS TIME. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH THIS EVENING FOR COZ067-068.
&&
$$
UPDATE...ROSE
SHORT TERM...MOZLEY
LONG TERM...LW
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS PADUCAH KY
244 PM CDT SUN AUG 2 2015
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 244 PM CDT SUN AUG 2 2015
COULD SEE A FEW ISOLATED SHOWERS OR STORMS THIS AFTERNOON OVER
SOUTHEAST MISSOURI AND SOUTHERN ILLINOIS. SO FAR IT HAS BEEN A
STRUGGLE TO COME UP WITH ENOUGH MOISTURE TO GET SOMETHING
GOING...BUT THE HRRR HAS BEEN CONSISTENTLY SHOWING DEVELOPMENT
THIS AFTERNOON. IT APPEARS THAT INDIVIDUAL CELLS WILL TRY TO MOVE
EAST...AND PROPAGATE SOUTHWARD INTO THE HIGHER THETA-E AIR. FIGURE
ANY CONVECTION WILL BE DONE BY SUNSET.
HAVE OPTED TO KEEP LATE TONIGHT AND MONDAY MORNING DRY. THE 12Z
MODELS CONTINUE TO HINT AT SOME CONVECTION MOVING OFF OF THE
APPROACHING COLD FRONT AND FLIRTING WITH SOUTHWEST INDIANA
STRADDLING 12Z MONDAY. IN GENERAL THE MODELS HAVE A WEAKENING
TREND WITH THIS ACTIVITY AS IT APPROACHES THE AREA...AND
NEIGHBORING FORECAST OFFICES PREFER TO KEEP THE FORECAST DRY...SO
HAVE FOLLOWED SUIT HERE.
THE FRONT MAY PROVIDE A FOCUS FOR THUNDERSTORM DEVELOPMENT MONDAY
AFTERNOON AND NIGHT. THE PROBLEMS ARE WHETHER THERE WILL BE ENOUGH
CONVERGENCE TO AID IN CONVECTIVE INITIATION...AND WHERE EXACTLY
IT WILL BE. THE 12Z MODEL CONSENSUS INDICATES THAT IT SHOULD BE
CUTTING ABOUT HALF WAY THROUGH THE AREA BY AFTERNOON...BUT IT IS
NOT CLEAR WHETHER IT WILL PUSH THROUGH THE ENTIRE AREA BY
EVENING...OR WHETHER IT WILL STALL OUT OVER THE AREA. IF IT DOES
FOCUS CONVECTION IT WILL STAND A BETTER CHANCE OF PUSHING THROUGH
THE AREA. WILL HAVE SMALL CHANCE POPS MAINLY ACROSS THE NORTHERN
HALF OF THE REGION FOR THE AFTERNOON AND THROUGH THE NIGHT.
THE BOUNDARY IS EXPECTED TO TAKE ON MORE OF A WARM FRONTAL LOOK
TUESDAY AND TUESDAY NIGHT...AS IT SETS UP ALONG/NEAR I-64.
CERTAINLY COULD SEE IT PROVIDE A FOCUS FOR CONVECTIVE
DEVELOPMENT...SO WILL CONTINUE WITH THE SMALL CHANCES FOCUSED IN
THE NORTH TUESDAY. WILL THEN INCREASE THEM SOME TUESDAY NIGHT AS
A MID/UPPER-LEVEL SYSTEM APPROACHES THE REGION.
TEMPERATURES ARE RUNNING COOL IN MOST LOCATIONS THIS
AFTERNOON...COMPARED TO THE GUIDANCE FROM YESTERDAY...AND THIS HAS
BEEN THE TREND FOR AWHILE NOW. THEREFORE...WILL STAY ON THE COOL
SIDE OF THE RANGE OF GUIDANCE FOR HIGHS MONDAY AND TUESDAY. LEANED
TOWARD THE WARM SIDE OF GUIDANCE FOR LOWS.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 244 PM CDT SUN AUG 2 2015
LATEST MODEL RUNS ARE IN PRETTY GOOD AGREEMENT SHOWING FAIRLY
WIDESPREAD QPF ACROSS THE PAH FORECAST AREA WEDNESDAY AND WEDNESDAY
NIGHT AS A SURFACE LOW MOVES JUST NORTH OF THE AREA. LATEST ECMWF
AND CANADIAN ARE IN FAIRLY CLOSER AGREEMENT IN PLACEMENT AND TIMING,
AND THIS OVERALL GIVES A LITTLE MORE CONFIDENCE IN GOING HIGH CHANCE
TO LIKELY POPS FOR SHOWERS AND THUNDERSTORMS FOR THESE PERIODS. A
GOOD CHANCE OF SHOWERS AND STORMS WILL CONTINUE INTO THURSDAY,
DECREASING FROM NORTHWEST TO SOUTHEAST THURSDAY NIGHT AS THE
ASSOCIATED COLD FRONT PUSHES THROUGH THE REGION. ECMWF AND GFS
IMPLY SOME LINGERING PRECIP CHANCES ON FRIDAY, SO KEPT SOME SLIGHT
TO LOW CHANCE POPS GOING FOR NOW. FOR FRIDAY NIGHT AND INTO THE
WEEKEND, SURFACE HIGH PRESSURE OVER THE GREAT LAKES REGION WILL KEEP
OUR AREA DRY.
CONDITIONS WILL REMAIN WARM AND MUGGY WEDNESDAY THROUGH THURSDAY
WITH SOUTHERLY FLOW AHEAD OF THE SURFACE PUMPING WARM MOIST AIR
NORTHWARD. HIGH TEMPERATURES WILL REACH NEAR NORMAL READINGS IN THE
MIDDLE TO UPPER 80S, WITH DEW POINTS GENERALLY IN THE LOWER 70S.
WITH THE COLD FRONT MOVING ACROSS THE AREA THURSDAY NIGHT, HIGH
TEMPERATURES FRIDAY AND THROUGH THE WEEKEND WILL OVERALL BE IN THE
80 TO 85 DEGREE RANGE, WITH DEW POINTS DROPPING BACK INTO THE LOWER
TO MIDDLE 60S.
&&
.AVIATION...
ISSUED AT 1230 PM CDT SUN AUG 2 2015
VFR CONDITIONS THROUGHOUT THE TAF PERIOD. THERE IS SOME POTENTIAL
OF VCTS AROUND KCGI THIS AFTERNOON BUT CONFIDENCE TOO LOW TO
INCLUDE. WILL WATCH TRENDS AND AMEND IF NECESSARY. SCATTERED CU
WILL BE PRESENT AT KCGI AND KPAH THIS AFTERNOON. OTHERWISE LIGHT
SOUTHERLY WINDS TODAY VEER AROUND TO WESTERLY TMRW AS WEAK FRONT
PUSHES THRU. VCTS COULD BE ASSOCIATED WITH THIS FRONT BY THE END
OF THE TAF PERIOD AT KEVV AND KOWB BUT PROBABILITY IS LOW AT THIS
TIME.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...RST
AVIATION...SP
AREA FORECAST DISCUSSION
NWS JACKSON KY
120 PM EDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1038 AM EDT SUN AUG 2 2015
MUCH OF THE FOG THAT DEVELOPED ACROSS THE RIVER VALLEYS THIS
MORNING HAS DISSIPATED. WE ARE LEFT WITH MOSTLY SUNNY TO SUNNY
SKIES UNDER SURFACE HIGH PRESSURE. FORECAST IS ON TRACK AT THIS
POINT WITH ONLY MINOR ADJUSTMENTS MADE OVERALL TOWARDS LATEST OBS
AND TRENDS.
UPDATE ISSUED AT 700 AM EDT SUN AUG 2 2015
TOUCHED UP THE GRIDS THIS MORNING BASED ON THE LATEST OBS AND
TRENDS. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 350 AM EDT SUN AUG 2 2015
07Z SFC ANALYSIS SHOWS HIGH PRESSURE IN PLACE OVER CENTRAL
KENTUCKY. THIS IS HELPING TO KEEP THE SKY MOSTLY CLEAR ACROSS THE
STATE...BUT A SMATTERING OF MID LEVEL CLOUDS ARE DRIFTING OVER
EAST KENTUCKY AND OUT OF THE AREA ATTM. SIMILAR TO THE PAST FEW
NIGHTS...AN INVERSION HAS SET UP WHILE GOOD RADIATIONAL COOLING IS
UNDERWAY. THIS HAS LED TO ANOTHER NIGHT OF RIDGE TO VALLEY
TEMPERATURE DIFFERENCES WITH SOME UPPER 50S FOUND IN THE DEEPER
SPOTS WHILE HILLTOPS ARE RUNNING IN THE MID 60S. WINDS REMAIN
LIGHT TO CALM ACROSS EAST KENTUCKY WITH NOT MUCH EVIDENCE OF FOG
OUT THERE YET. HOWEVER...AGAIN SIMILAR TO THE PAST FEW NIGHTS...
EXPECT THE FOG TO FORM IN THE RIVER VALLEYS BEFORE DAWN ALONG WITH
LOCALLY DENSE PATCHES.
THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT AS A BROAD AREA OF
TROUGHING CONTINUES OVER SOUTH CENTRAL CANADA AND DOWN INTO THE
OHIO VALLEY ACROSS TO NEW ENGLAND. A WIGGLE AT THE CORE OF THE
TROUGH TO THE NORTH WILL SEND A LARGE AMOUNT OF ENERGY INTO THE
GREAT LAKES ON MONDAY ALONG WITH A MID LEVEL GRADIENT THAT
TIGHTENS...RESULTING IN FASTER FLOW THROUGH THE OHIO VALLEY. GIVEN
THE AGREEMENT ALOFT WILL FOLLOW A BLENDED SOLUTION WITH EMPHASIS
ON THE HRRR AND NAM12 EARLY ON AND THE BROADER CONSENSUS LATER.
SENSIBLE WEATHER WILL FEATURE ANOTHER PLEASANT DAY WITH FAIRLY LOW
AND COMFORTABLE HUMIDITY LEVELS AND HIGHS GENERALLY IN THE MID
80S UNDER MOSTLY SUNNY SKIES. THIS WILL LEAD INTO ONE MORE NIGHT
OF GOOD RADIATIONAL COOLING AND RIDGE TO VALLEY TEMPERATURE
DIFFERENCES INTO MONDAY MORNING...ALONG WITH PATCHY VALLEY FOG
TOWARDS DAWN. BY MONDAY...THOUGH...THE SFC PATTERN WILL CHANGE
WITH A COLD FRONT PRESSING SOUTH THROUGH THE OHIO VALLEY AND
TOWARD EAST KENTUCKY. THIS WILL LIKELY KICK OFF SHOWERS AND
THUNDERSTORMS NORTH OF THE STATE THAT SHOULD HELP TO SPAWN
ADDITIONAL STORMS TO THE SOUTH WITH TIME THROUGH THE DAY. ANY
STORMS THAT MANAGE TO DEVELOP OUT AHEAD OF THE FRONT IN EAST
KENTUCKY WILL HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE OWING
TO HIGH CAPES AND STRENGTHENING MID LEVEL WINDS. THE BEST CHANCES
WILL BE OVER OUR NORTHERN ZONES CLOSER TO THE FRONT AND SPC HAS
INDICATED A SLIGHT RISK FOR SEVERE STORMS THERE. WILL HIGHLIGHT
THIS CONCERN IN THE FORTHCOMING HWO.
STARTED WITH THE SHORTBLEND MODEL FOR THE T/TD/WIND GRIDS THROUGH
THE DAY FOLLOWED BY THE SUPERBLEND INTO MONDAY. DID MAKE SOME
SIGNIFICANT ADJUSTMENTS TO TEMPERATURES THIS MORNING AND TONIGHT
WITH RESPECT TO RIDGE AND VALLEY DIFFERENCES. AS FOR POPS...KEPT
THEM LOW AND IN LINE WITH THE DRY GUIDANCE INTO MONDAY MORNING.
DID GO A BIT HIGHER THAN THE MET AND MAV NUMBERS FOR MONDAY
AFTERNOON TO ACCOUNT FOR THE POTENTIAL INTRUSION OF STORMS...
ORGANIZED OR OTHERWISE...FROM THE NORTH BY EVENING.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 340 AM EDT SUN AUG 2 2015
THE EXTENDED FORECAST PERIOD BEGINS ON MONDAY NIGHT WITH THE UPPER
LEVEL PATTERN MAINTAINING A RIDGE OVER THE WEST AND THE LONGWAVE
TROUGH OVER THE EASTERN CONUS. A CLOSED LOW OVER THE HUDSON BAY AREA
WILL GRADUALLY SHIFT OFF TO THE EAST THROUGH THE EXTENDED AS BY
THURSDAY...A SERIES OF STRONGER TROUGHS COME ASHORE OVER THE WEST AS
THE WESTERN RIDGE BEGINS TO WEAKEN A BIT AND SHIFT EAST. THIS
THROUGH THE LAST PORTION OF THE EXTENDED WILL BE THE FORECAST
CHALLENGE AS THE BASE OF THE EASTERN TROUGH SETS UP OVER THE MID MS
VALLEY AND THROUGH KY. THE GFS AND EURO DOES ALIGN A BIT WITH THIS
SOLUTION.
CLOSER TO THE SURFACE...THE FRONT THAT HAS PASSED THROUGH ON MONDAY
WILL LAG ACROSS NORTHERN KENTUCKY AS A STATIONARY BOUNDARY DEVELOPS.
THIS AREA BECOMES A FOCUS FOR SHOWER AND THUNDERSTORM DEVELOPMENT AS
THE BOUNDARY SLIDES FURTHER SOUTH THROUGH THE DAY ON TUESDAY AND
TUESDAY NIGHT. BY WEDNESDAY...NORTHWEST FLOW SETS UP OVER THE AREA
AS A SERIES OF UPPER LEVEL WAVES TOPPLE OVER THE THE TOP OF THE
WESTERN RIDGE AND TRACK SOUTHEAST INTO THE OH VALLEY. THE SUPER
BLEND HAS THIS IN IT/S SOLUTION AS WELL WITH THE PATTERN FAVORABLE
FOR NOCTURNAL THUNDERSTORMS AS WELL...ESPECIALLY IF THIS PATTERN FOR
MCS/S REMAIN...WHICH SEEMS LIKELY BASED UPON THE GFS AND EURO
SOLUTIONS . THUS WILL STAY CLOSE TO THE SUPER BLENDS SOLUTION
WEDNESDAY THROUGH FRIDAY KEEPING HIGH CHANCE TO LIKELY POPS DURING
THIS PERIOD.
TOWARDS THE END OF THE EXTENDED ON FRIDAY AND SATURDAY...THE UPPER
LEVEL PATTERN LOSES A BIT AMPLITUDE AND BECOMES MORE ACTIVE AS
ANOTHER SHORTWAVE TAKES AIM AT THE OH VALLEY. HOWEVER...THE GFS AND
EURO DO DIVERGE TOWARDS THE END OF THE EXTENDED. THUS...LACKING
CONFIDENCE...WILL GO NEAR OR SLIGHTLY BELOW THE SUPER BLEND ON POPS.
THE LINGERING TROUGH OVER THE EAST AND SAGGING SOUTH THROUGH THE
EXTENDED WILL KEEP HIGHS AT OR SLIGHTLY BELOW NORMAL FOR THIS TIME
OF YEAR. IN SHORT...THE WEDNESDAY THROUGH FRIDAY PERIOD SEEMS TO BE
QUITE ACTIVE AND WET WITH THE END OF THE FORECAST POSSIBLY
CONTINUING THIS TREND WITH A COOLING TREND AS WELL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 120 PM EDT SUN AUG 2 2015
HIGH PRESSURE WILL KEEP TAF SITES MOSTLY VFR THROUGH THE TAF
PERIOD. THE EXCEPTION TO THE RULE WILL BE MAINLY RIVER VALLEY FOG
ACROSS THE REGION OVERNIGHT INTO EARLY MONDAY MORNING. WHILE THIS
WILL NOT AFFECT MOST TAF SITES...GIVEN SIMILAR PATTERN HAVE
INTRODUCED LOWER MVFR VIS SME...SJS...AND SYM WHICH HAD THE MOST
AFFECTS FROM FOG THIS MORNING. THERE IS ALSO AN APPROACHING COLD
FRONT AS WE MOVE INTO AFTERNOON HOURS ON MONDAY...BUT STILL
UNCERTAINTY ON HOW QUICKLY WE WILL SEE CONVECTION ACROSS NORTHERN
TAF SITES. THEREFORE WILL HOLD OFF ON ANY MENTION IN THE TAFS AT
THIS TIME GIVEN LOWER CONFIDENCE. WINDS THROUGH THE PERIOD ARE
EXPECTED TO REMAIN LIGHT AND VARIABLE.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...DJ
SHORT TERM...GREIF
LONG TERM...SHALLENBERGER
AVIATION...DJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
344 PM EDT SUN AUG 2 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 343 PM EDT SUN AUG 2 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW STRONG SHRTWV
APRCHG THE UPR GREAT LKS IN DEEP CYC NW FLOW ARND CLOSED LO OVER FAR
NRN ONTARIO. THERE HAVE BEEN WAVES OF SHOWERS/ELEVATED TS THAT HAVE
MOVED THRU UPR MI AS DPVA/DEEP LYR QVECTOR CNVGC AHEAD OF THE SHRTWV
HAS LIFTED UNSTABLE ENVIRONMENT SHOWN ON THE 12Z AND 18Z GRB RAOBS
/H7-5 LAPSE RATES AOA 8C/KM/. MOST OF THE TS HAVE IMPACTED LOCATIONS
NEAR THE WI BORDER WHERE RUC ANALYSIS MUCAPES HAVE BEEN UP TO 1000
J/KG UNDER AXIS OF HIER H85 THETA E. ALTHOUGH SOME OF THE STORMS
EARLIER THIS MRNG WERE SEVERE WITH LARGE HAIL...LOTS OF CLD COVER
OVER UPR MI HAVE MAINTAINED MORE ELEVATED CORES HAVE LIMITED THE
SEVERITY OF THE CONVECTION MOST OF THE DAY DESPITE IMPRESSIVE DEEP
LYR SHEAR ON THE ORDER OF 40-50 KTS UNDER RIBBON OF STRONG WNW WINDS
ALOFT. THE SHOWERS ARE TENDING TO DIMINISH OVER THE NW CWA WITH
ARRIVAL OF NEGATIVE H85 THETA E ADVECTION/MID-LVL DRYING/DEEP LYR
QVECTOR DVGC AND MORE MARGINAL LAPSE RATES DEPICTED ON THE 12Z INL
RAOB.
LATE THIS AFTN...WHILE MORE NMRS SHOWERS/TS MAY IMPACT THE SE
CWA...THE ARRIVAL OF MORE MARGINAL LAPSE RATES ACCOMPANYING DEEP LYR
QVECTOR CNVGC WL LIMIT THE COVERAGE/INTENSITY OF THIS CONVECTION.
TNGT...AFTER ANY LINGERING SHOWERS/TS OVER THE SE CWA END AFTER
EARLY EVNG...LARGER SCALE SUBSIDENCE/DRYING IN THE WAKE OF PASSING
SHRTWV WL BRING A CLEARING TREND. AS UPR TROF AMPLIFIES INTO THE UPR
LKS...LLVL SLGTLY CYC NW FLOW BEHIND COLD FROPA IS FCST TO DROP H85
TEMPS AS LO AS 6 TO 7C BY 12Z MON. WITH THIS THERMAL TROF...EXPECT
INCRSG LO CLDS LATE...ESPECIALLY OVER THE HIER TERRAIN OF THE NW
CWA.
MON...CYC H85 NW FLOW IS PROGGED TO PERSIST AND MAINTAIN THERMAL
TROF OVER THE CWA...SO EXPECT A GOOD DEAL OF CLD COVER. COMBINATION
OF DATYIME HEATING AND PASSING SHRTWV MAY BRING SOME SCT SHOWERS...
MAINLY OVER THE INTERIOR AWAY FM LK SUP MODERATION IN THE AFTN. WITH
H85 TEMPS FCST IN THE 8 TO 10C RANGE...EXPECT MAX TEMPS MAINLY IN
THE 60S...EXCEPT 70 TO 75 IN THE DOWNSLOPE AREAS OF THE SCENTRAL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 344 PM EDT SUN AUG 2 2015
SPENT A CONSIDERABLE AMOUNT OF TIME WORKING SHORT FUSE OPERATIONS
TODAY GIVEN IMPACTS IN THE SHORT TERM AND LACK OF SIGNIFICANT
IMPACTS IN THE LONG TERM. ADDITIONALLY...CONSENSUS GUIDANCE HAS A
GOOD HANDLE ON THE LONG TERM SITUATION SO TIME WAS BEST SPENT
HELPING IN THE SHORT TERM.
BASIC IDEA IS THAT WITH AN UPPER LOW MOVES NE OF THE CWA MON NIGHT
INTO TUE...COULD SEE SHOWERS AND MAYBE T-STORMS DUE TO DECREASED MID-
UPPER LEVEL TEMPS AND SHORTWAVE ENERGY ROTATING THROUGH. BEST
COVERAGE SHOULD BE DURING THE DAY ON TUE WITH GREATEST SFC HEATING.
WED LOOKS DRY WITH A SFC RIDGE OVERHEAD. THU THROUGH FRI MAY BE DRY
AS WELL...BUT REGIONAL CONDITIONS WILL BE MORE IMPACTED BY AN
INCREASE IN SHORTWAVE ACTIVITY AND A RESULTING INCREASE IN
UNCERTAINTY. SHOULD SEE BETTER CHANCES FOR PRECIP NEXT WEEKEND...BUT
THAT IS QUITE UNCERTAIN AS WELL. OVERALL...LEANED HEAVILY ON
CONSENSUS GUIDANCE FOR MOST OF THE LONG TERM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 156 PM EDT SUN AUG 2 2015
SOME SHRA AND PERHAPS A TS IN ADVANCE OF AN APRCHG COLD FNT WL
IMPACT MAINLY SAW THRU THIS AFTN. ALTHOUGH SOME LOWER CIGS/VSBYS
COULD ACCOMPANY THE HEAVIER SHOWERS...VFR CONDITIONS SHUD
PREDOMINATE. FOLLOWING THE COLD FROPA/WSHFT TO THE NW AND ARRIVAL OF
DRIER LLVL AIR THIS AFTN...THE SHRA THREAT WL END...AND SKIES WL
TURN PCLDY. MORE LOWER CLDS WL ARRIVE AS EARLY AS LATE TNGT OVER THE
KEWEENAW AND THEN EXPAND TO IWD/SAW WITH INCRSG LLVL MSTR. ALTHOUGH
THERE COULD A -SHRA...VFR CONDITIONS WL BE THE RULE WITH A WELL
MIXED/DRY NEAR SFC LYR. BEST CHC FOR A LOWER MVFR CIG WOULD BE AT
CMX WITH FVRBL UPSLOPE WIND COMPONENT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 343 PM EDT SUN AUG 2 2015
EXPECT WNW WINDS UP TO 20 KTS INTO MID WEEK AROUND DEEP LO PRES NEAR
HUDSON BAY. THE ARRIVAL OF A HI PRES RIDGE LATER IN THE WEEK WILL
RESULT IN LIGHT WINDS UNDER 15 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...TITUS
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
343 PM EDT SUN AUG 2 2015
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 343 PM EDT SUN AUG 2 2015
12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW STRONG SHRTWV
APRCHG THE UPR GREAT LKS IN DEEP CYC NW FLOW ARND CLOSED LO OVER FAR
NRN ONTARIO. THERE HAVE BEEN WAVES OF SHOWERS/ELEVATED TS THAT HAVE
MOVED THRU UPR MI AS DPVA/DEEP LYR QVECTOR CNVGC AHEAD OF THE SHRTWV
HAS LIFTED UNSTABLE ENVIRONMENT SHOWN ON THE 12Z AND 18Z GRB RAOBS
/H7-5 LAPSE RATES AOA 8C/KM/. MOST OF THE TS HAVE IMPACTED LOCATIONS
NEAR THE WI BORDER WHERE RUC ANALYSIS MUCAPES HAVE BEEN UP TO 1000
J/KG UNDER AXIS OF HIER H85 THETA E. ALTHOUGH SOME OF THE STORMS
EARLIER THIS MRNG WERE SEVERE WITH LARGE HAIL...LOTS OF CLD COVER
OVER UPR MI HAVE MAINTAINED MORE ELEVATED CORES HAVE LIMITED THE
SEVERITY OF THE CONVECTION MOST OF THE DAY DESPITE IMPRESSIVE DEEP
LYR SHEAR ON THE ORDER OF 40-50 KTS UNDER RIBBON OF STRONG WNW WINDS
ALOFT. THE SHOWERS ARE TENDING TO DIMINISH OVER THE NW CWA WITH
ARRIVAL OF NEGATIVE H85 THETA E ADVECTION/MID-LVL DRYING/DEEP LYR
QVECTOR DVGC AND MORE MARGINAL LAPSE RATES DEPICTED ON THE 12Z INL
RAOB.
LATE THIS AFTN...WHILE MORE NMRS SHOWERS/TS MAY IMPACT THE SE
CWA...THE ARRIVAL OF MORE MARGINAL LAPSE RATES ACCOMPANYING DEEP LYR
QVECTOR CNVGC WL LIMIT THE COVERAGE/INTENSITY OF THIS CONVECTION.
TNGT...AFTER ANY LINGERING SHOWERS/TS OVER THE SE CWA END AFTER
EARLY EVNG...LARGER SCALE SUBSIDENCE/DRYING IN THE WAKE OF PASSING
SHRTWV WL BRING A CLEARING TREND. AS UPR TROF AMPLIFIES INTO THE UPR
LKS...LLVL SLGTLY CYC NW FLOW BEHIND COLD FROPA IS FCST TO DROP H85
TEMPS AS LO AS 6 TO 7C BY 12Z MON. WITH THIS THERMAL TROF...EXPECT
INCRSG LO CLDS LATE...ESPECIALLY OVER THE HIER TERRAIN OF THE NW
CWA.
MON...CYC H85 NW FLOW IS PROGGED TO PERSIST AND MAINTAIN THERMAL
TROF OVER THE CWA...SO EXPECT A GOOD DEAL OF CLD COVER. COMBINATION
OF DATYIME HEATING AND PASSING SHRTWV MAY BRING SOME SCT SHOWERS...
MAINLY OVER THE INTERIOR AWAY FM LK SUP MODERATION IN THE AFTN. WITH
H85 TEMPS FCST IN THE 8 TO 10C RANGE...EXPECT MAX TEMPS MAINLY IN
THE 60S...EXCEPT 70 TO 75 IN THE DOWNSLOPE AREAS OF THE SCENTRAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 334 AM EDT SUN AUG 2 2015
TEMPS WILL BE BLO NORMAL THIS WEEK AS GREAT LAKES IS WITHIN DIRECT
INFLUENCE OF STRONG UPPER TROUGH CENTERED ON ONTARIO AND QUEBEC AND
ASSOCIATED SFC LOW SPINNING OVER QUEBEC. BASED ON THE WV LOOP AND IR
SATELLITE LOOPS AND 00Z H5 RAOBS...STRONGEST SHORTWAVES AROUND THE
UPPER LOW CENTER ARE CURRENTLY WEST OF JAMES BAY...DROPPING OVER
NORTHEAST MANITOBA...AND ROTATING NORTHWEST ALONG EAST SHORE OF
HUDSON BAY. MODELS IN GENERAL SHOW THE INTENSITY OF INDIVIDUAL WAVES
FADING THROUGH TUESDAY...BUT THAT MAY OR MAY NOT OCCUR. ONLY SAY
THAT AS MODELS TYPICALLY DOWNPLAY STRENGTH OF SHORTWAVES ROTATING
AROUND A LARGE UPPER LOW THE FARTHER OUT IN TIME YOU ARE. SUPPOSE
THAT IF ONE OF THESE WAVES SLIDES ACROSS DURING THE PEAK HEATING OF
THE DAY MONDAY OR TUESDAY...WITH ALREADY COOL AIR ALOFT/HIGHER H925-
H7 RH IN PLACE...THERE WOULD BE AN UPTICK OF COVERAGE AND INTENSITY
OF SHOWERS AND AT LEAST SOME POTENTIAL OF TSRA. 00Z SOUNDING FM CYYQ
AT CHURCHILL MANITOBA SHOWED MOISTURE FM NEAR SFC THROUGH H7...SO
IDEA THAT MODELS ARE SHOWING FOR EARLY THIS WEEK WITH HIGHER RH
THROUGH H7 SEEM ON TRACK. WENT AHEAD AND INCREASED POPS TO AT LEAST
CHANCE RANGE OVER INTERIOR CNTRL ON MONDAY AFTN AND TUESDAY AFTN.
SFC RIDGE BEGINS TO BUILD FM CNTRL CANADA INTO UPPER GREAT LAKES AND
OHIO VALLEY TUESDAY NIGHT AND MORE SO INTO WEDNESDAY. LESS IN WAY OF
H85-H7 Q-VECTOR CONVERGENCE AND HIGHER RH DURING THIS TIME AS WELL
SO SHOULD SEE MINIMAL CHANCES FOR ANY SHRA. A BIT MORE MESSY IN
PREDICTABILITY LATER THIS WEEK. 12Z ECMWF SHOWED ANOTHER SHORTWAVE
DROPPING OVER THE UPPER GREAT LAKES IN SLOW TO LET GO NW FLOW ALOFT
ON EDGE OF UPPER LEVEL TROUGH...WHILE GFS CONTINUES TO TAKE
SHORTWAVE CURRENTLY OVER CA/NV AND BRINGS IT ACROSS WESTERN CONUS
RIDGE AND OVER NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER VALLEY
WEDNESDAY NIGHT INTO THURSDAY. INTERESTING ENOUGH THE 00Z ECMWF IS
SIMILAR TO GFS...JUST NOT AS FAR NORTH WITH THAT SHORTWAVE AND
ASSOCIATED QPF. MEANWHILE...GEM-NH BRINGS SHORTWAVE OVER EASTERN
PACIFIC OFFSHORE OF CA THIS MORNING AND TAKES IT SLOWLY OVER ROCKIES
AND NORTHERN PLAINS...WITH ARRIVAL OVER UPPER MISSISSIPPI RIVER
VALLEY THURSDAY INTO FRIDAY. GIVEN ALL THE DIFFERENT SCENARIOS WILL
STICK WITH SLIGHT CHANCE POPS OFFERED UP BY A MODEL
CONSENSUS...MAINLY FOCUSED ALONG WI BORDER. SEEMS THAT THERE IS
BETTER AGREEMENT THAT BY FRIDAY EVENING...SHORTWAVE AND ASSOCIATED
WEAK SFC LOW WILL BE SOUTH OF UPR MICHIGAN AS HIGH PRESSURE RIDGE
OVER CNTRL CANADA BUILDS ACROSS INTO UPPER GREAT LAKES.
SINCE HIGH PRESSURE RIDGE CENTER FOCUSES OVER NORTHERN ONTARIO AND
QUEBEC NEXT WEEKEND...MAY SEE POTENTIAL FOR LAKE BREEZES TO HELP FORM
SHRA OR TSRA GIVEN ENOUGH DAYTIME HEATING/INSTABILITY. STILL LOOKING
LIKE VERY LOW CHANCE THOUGH.
OVERALL FOR THIS WEEK THE COOL TEMPERATURES WILL BE THE BIGGER STORY.
WILL BE DEALING WITH CHILLY SUMMER AIRMASS FOR SURE AS H85 TEMPS ARE
FORECAST TO DROP TO 0-1C OVER NORTHERN ONTARIO BY 12Z MONDAY. COOL
AIR MODERATES SOME BUT H85 TEMPS STILL FALL OFF TO AS LOW AS 3-5C
OVER UPR MICHIGAN BY TUESDAY AFTN. EXPECT HIGH TEMPS MONDAY TO BE IN
THE UPPER 60S TO LOW 70S...COOLEST NEAR LK SUPERIOR. TEMPS ON TUESDAY
WILL BE COOL EVERYWHERE. READINGS ALONG LK SUPERIOR MAY STAY BLO 60
DEGREES WITH PERSISTENT NORTHWEST GRADIENT WIND. TEMPS INLAND AND
NEAR LK MICHIGAN WILL MOSTLY BE IN THE 60S. ONLY SCNTRL FM IMT TO ESC
AND SOUTH TO MNM MAY SEE TEMPS CRACK 70 DEGREES. OVERNIGHT LOWS MONDAY
NIGHT AND TUESDAY NIGHT WILL BE REFRESHING WITH 40S AND 50S. SEEMS TO
BE ENOUGH NORTHWEST GRADIENT WIND EVEN ON TUESDAY NIGHT TO KEEP LOWS
FM DROPPING BLO 40 DEGREES AND KEEPING FROST POTENTIAL TO A MINIMUM.
H85 TEMPS BEGIN TO BOUNCE BACK TO 5-8C ON WEDNEDAY AFTN...SUPPORTING
HIGHS BACK INTO THE 70S FOR MUCH OF THE CWA...THOUGH PROBABLY WILL BE
LOWER 70S FOR MOST WHICH IS STILL BLO NORMAL. TEMPS TO END THE WEEK
WILL REMAIN ON THE COOLER SIDE OF NORMAL. DESPITE MOST OF THE RAIN
STAYING SOUTH OF CWA THURSDAY INTO FRIDAY...INCREASE IN CLOUDS AND
NORTHEAST GRADIENT WIND BTWN HIGH OVER MANITOBA AND NORTHERN ONTARIO
AND TROUGHING IN THE NORTHERN PLAINS AND UPPER MISSISSIPPI RIVER
VALLEY WILL KEEP MAX TEMPS IN THE UPR 60S TO LOW 70S. A BIT OF
WARMING AT H85 BY NEXT WEEKEND SHOULD PUSH TEMPS AT LEAST INLAND FM
LK SUPERIOR BACK INTO THE MID 70S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 156 PM EDT SUN AUG 2 2015
SOME SHRA AND PERHAPS A TS IN ADVANCE OF AN APRCHG COLD FNT WL
IMPACT MAINLY SAW THRU THIS AFTN. ALTHOUGH SOME LOWER CIGS/VSBYS
COULD ACCOMPANY THE HEAVIER SHOWERS...VFR CONDITIONS SHUD
PREDOMINATE. FOLLOWING THE COLD FROPA/WSHFT TO THE NW AND ARRIVAL OF
DRIER LLVL AIR THIS AFTN...THE SHRA THREAT WL END...AND SKIES WL
TURN PCLDY. MORE LOWER CLDS WL ARRIVE AS EARLY AS LATE TNGT OVER THE
KEWEENAW AND THEN EXPAND TO IWD/SAW WITH INCRSG LLVL MSTR. ALTHOUGH
THERE COULD A -SHRA...VFR CONDITIONS WL BE THE RULE WITH A WELL
MIXED/DRY NEAR SFC LYR. BEST CHC FOR A LOWER MVFR CIG WOULD BE AT
CMX WITH FVRBL UPSLOPE WIND COMPONENT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 343 PM EDT SUN AUG 2 2015
EXPECT WNW WINDS UP TO 20 KTS INTO MID WEEK AROUND DEEP LO PRES NEAR
HUDSON BAY. THE ARRIVAL OF A HI PRES RIDGE LATER IN THE WEEK WILL
RESULT IN LIGHT WINDS UNDER 15 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
146 PM EDT SUN AUG 2 2015
.AVIATION...
THUNDERSTORMS TO THE NORTH SHOULD CONGEAL AND DROP SOUTH THROUGH
AREA THIS EVENING AS A COLD FRONT DROPS SOUTH THROUGH THE CENTRAL
GREAT LAKES. EXPECT A DECENT CHANCE OF A POCKETS OF SEVERE WEATHER
WITHIN THIS EXPECTED AREA OF THUNDERSTORMS...WHICH WILL MOST LIKELY
PROGRESS FROM MBS AT 00Z-01Z TO THE I-94 TERMINALS BY 03Z-05Z AND
THEN EXIT SOUTH OF WHOLE AREA AFTER 06-07Z. OTHERWISE THAN PATCHY
LATE NIGHT FOG TONIGHT...VFR CONDITIONS SHOULD...ONCE AGAIN...BE THE
RULE ONCE THE STORMY WEATHER ENDS TONIGHT.
FOR DTW...MOST PROBABLE TIME FOR TSTORMS WILL BE 03-06Z IN ADVANCE
OF APPROACHING COLD FRONT.
//DTW THRESHOLD PROBABILITIES...
* LOW FOR TSTORMS THIS AFTN. MEDIUM AFTER 03Z TONIGHT.
&&
.PREV DISCUSSION...ISSUED 1153 AM EDT SUN AUG 2 2015
UPDATE...
FORECAST REMAINS IN GOOD SHAPE AS CONVECTIVE EVOLUTION TO OUR
NORTH HAS BEEN FAIRLY PREDICTABLE TO THIS POINT. SEVERAL CLUSTERS
OF STORMS CONTINUE TO PEEL EASTWARD ACROSS NORTHERN WISCONSIN ON
INTO THE UP AND NORTHERN LOWER MICHIGAN. THUNDERSTORM CHANCES WILL
INCREASE OVER THE NORTHERN CWA THIS AFTERNOON AS THE FLOW OF WARM
AND MOIST AIR PERSISTS AND A LARGE OUTFLOW BOUNDARY ALONG THE
SOUTHERN EDGE OF STORM COMPLEXES TO THE NORTH SETTLES INTO THE
FORECAST AREA AND PROVIDES FOCUS FOR THIS INCREASINGLY UNSTABLE
AIRMASS. WHILE AN ISOLATED STORM CANNOT BE RULED OUT AS FAR SOUTH
AS M 59 LATER THIS AFTERNOON...MOST ACTIVITY WILL REMAIN NORTH OF
THE I-69 CORRIDOR.
IT LOOKS INCREASINGLY LIKE THE NEXT ROUND OF THUNDERSTORMS WILL
ACTUALLY OVERLAP WITH THIS ONGOING ACTIVITY AS OPPOSED TO BEING A
MORE DISTINCT EPISODE. A CONTINUED FLOW OF MOIST/UNSTABLE AIR
ALONG THE AFOREMENTIONED OUTFLOW BOUNDARY SHOULD MAINTAIN FAIRLY
CONSISTENT CONVECTION ALONG/NORTH OF THE CWA INTO EARLY THIS
EVENING WITH ADDITIONAL DEVELOPING ACTIVITY ALONG APPROACHING
COLD FRONT THEN SPREADING INTO THE AREA FROM NORTHERN LOWER
MICHIGAN AND WISCONSON DURING THE COURSE OF THE EVENING...WHICH
WILL ACT TO DRAG EXISTING CONVECTION ALONG THE NORTHERN BORDER
SOUTHWARD INTO THE AREA.
NET RESULT WILL BE THE SAME AS STORM CHANCES INCREASE FROM NORTH
TO SOUTH ACROSS THE AREA FROM MID TO LATE EVENING. TIMING FOR
LARGEST THREAT OF STORMS FOR METRO DETROIT STILL APPEARS TO BE
MAINLY AFTER 10 PM AND PERHAPS CLOSER TO MIDNIGHT FOR MANY
LOCALES. WITH ANY LUCK...DECLINING INSTABILITY AT THIS LATER HOUR
WILL TAKE SOME PUNCH OUT OF THE LINE OF STORMS THAT EVENTUALLY
EVOLVES AND PROGRESSES INTO THE AREA LATER THIS EVENING. THAT
SAID...THE THREAT OF SEVERE WEATHER WILL PERSIST GIVEN THE STRONG
WIND FIELD AND AT LEAST A MODERATELY UNSTABLE AIRMASS AT THAT
POINT.
PREV DISCUSSION...ISSUED 526 AM EDT SUN AUG 2 2015
UPDATE...
A REFINEMENT OF THOUGHTS AFTER PERUSING FRESH ARRIVING HIGH
RESOLUTION GUIDANCE, PARTICULARLY THE RAP, HRRR AND 00Z 3KM
EXPERIMENTAL NAM WHICH APPEAR TO BE SHEDDING SOME LIGHT ON THIS
AFTERNOON AND EVENING`S SEVERE POTENTIAL. ALTHOUGH OVERALL FORECAST
REASONING HAS NOT CHANGED, NEW INFORMATION IS INCREASING CONFIDENCE
THAT AFTERNOON CONVECTION WILL REMAIN CONFINED TO NORTHERN AREAS
ALONG THE NOSE OF THE DEVELOPING LOW-LEVEL JET WHILE AREAS SOUTH OF
M59 REMAIN CAPPED THUS INHIBITING PREMATURE OVERTURNING.
IN ADDITION TO THE PRIMARY THREAT OF UPSCALE GROWTH OF CONVECTION
INTO AN ORGANIZED MCS, A FEW STORMS COULD ALSO DEVELOP IN ADVANCE OF
THIS LINE WITHIN THE CORRIDOR PRECEDING WARM ADVECTION. THIS
PREFRONTAL CONVECTION WILL HAVE STEEP LAPSE RATES AND AN APPRECIABLE
RESERVOIR OF INSTABILITY WITH WHICH TO WORK. THE OFT CONSERVATIVE
07Z RAP INDICATING 0-1KM MLCAPE APPROACHING 2500 J/KG IN MIDLAND/BAY
COUNTY BY 22Z. IN ADDITION, STRENGTHENING SWLY FLOW WILL SUPPORT
ELEVATED BULK SHEAR DURING THIS TIME THUS POTENTIALLY SUPPORTING A
FEW SUPERCELLS AS UPSTREAM CONVECTION ORGANIZES OVER WISCONSIN, LAKE
MICHIGAN, AND NORTHERN LOWER MICHIGAN. GIVEN WELL MIXED/DEEP
BOUNDARY LAYER INDICATED ON FORECAST SOUNDINGS, IT APPEARS THAT A
POTENTIALLY SIGNIFICANT/70MPH, IF RELATIVELY ISOLATED, WIND THREAT
MAY EXIST MAINLY INVOF THE SAGINAW VALLEY IN ADVANCE OF THE MAIN
LINE AS EARLY AS 21/22Z. FOR THE SAME REASON, TORNADO THREAT WOULD
APPEAR LIMITED DUE TO HIGH LCLS. THOUGH THIS AFTN/EVENING`S
CONVECTIVE TRENDS WILL STILL BE CRITICAL, LATEST GUIDANCE DOES
SUPPORT THE OFFICIAL FORECAST STRONGLY ENOUGH TO CONSIDER
ADVERTISING A THREAT FOR 70 MPH WIND GUSTS CONDITIONAL ON MCS
ORGANIZATION. WILL ALLOW TIME FOR UPDATED SPC DAY 1 AND FOR DAY CREW
TO EVALUATE LATEST TRENDS AND HIGH RES GUIDANCE BEFORE ELEVATING
WORDING IN THE HWO AND OTHER PRODUCTS.
FINALLY, AS NOTED IN THE ORIGINAL MORNING FORECAST PACKAGE, A
LIMITED SEVERE THREAT WILL EXIST WITH ANY CONVECTION THAT TRAVERSES
LAND ACROSS THE NORTH DURING THE AFTERNOON HOURS. IF LATEST RAP RUNS
ARE ANY INDICATION, THE THERMODYNAMIC ENVIRONMENT MAY EVOLVE A BIT
FASTER THAN PREVIOUSLY FORECAST YIELDING INCREASED CONFIDENCE IN
SEVERE WIND POTENTIAL AT LEAST OVER THE THUMB PERHAPS AS EARLY AS
18Z SHOULD UPSTREAM CONVECTION DEVELOP WITHIN FAVORABLE WAA/STEEP
LAPSE RATE ENVIRONMENT.
PREV DISCUSSION...ISSUED 252 AM EDT SUN AUG 2 2015
SHORT TERM...TODAY AND TONIGHT
SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVER MN AND WI DURING THE
PREDAWN HOURS AS A FAST-MOVING LEAD SHORTWAVE PROVIDES FORCING
WITHIN THE STEEP LAPSE RATE ENVIRONMENT BEING DRAWN EAST BY BROAD
CYCLONIC WNW FLOW. THIS ENVIRONMENT WILL RACE EAST THROUGH THE
AFTERNOON FOCUSING A CORRIDOR OF CONVECTION ACROSS PRIMARILY ACROSS
LAKE HURON AND NORTHERN LOWER MICHIGAN. SOUTHEASTERN PORTIONS OF THE
CWA WILL REMAIN LARGELY CAPPED THROUGH PEAK HEATING AS H85
TEMPERATURES RISE WELL INTO THE UPPER TEENS SUPPORTING HIGHS
APPROACHING 90F. HOWEVER, SLIGHTLY WEAKER CAPPING/BETTER FORCING
ACROSS THE NORTH WARRANT AT LEAST A HIGH CHC POP FROM THE SAGINAW
VALLEY INTO THE THUMB, INCREASING TO LIKELY BY LATE THIS AFTN. THIS
ACTIVITY WILL CARRY AT LEAST A LOW END SEVERE RISK 18-00Z NORTH OF
THE I-69 CORRIDOR AS IT WILL RESIDE ALONG THE EASTERN PERIPHERY MORE
STRONGLY SHEARED SWLY FLOW AND AS SURFACE TDS RISE INTO THE MID AND
UPPER 60S SUPPORTING MODERATE DESTABILIZATION. LATEST HRRR RUNS HAVE
A DEPICTION SIMILAR TO EXPECTATIONS, PARTICULARLY WRT TO EXPECTED
SOUTHWARD EXTENT. MEANWHILE 4KM SPC RUN APPEARS ENTIRELY TOO
GENEROUS WITH CONVECTIVE COVERAGE/EVOLUTION WITHIN STRONGLY CAPPED
AREAS.
SECOND AND POTENTIALLY GREATER SEVERE THREAT MAY EXIST TONIGHT,
LARGELY CONDITIONAL ON EXTENT OF PRECEDING AFTERNOON CONVECTION AND
QUALITY OF RECOVERY. DEVELOPING STRONG SWLY FLOW IN ADVANCE OF
PRIMARY TROUGH AXIS WILL CERTAINLY GIVE THE EXPECTED GENESIS AREA
OVER NORTHERN LOWER OR CENTRAL MI A DECENT SHOT AT RECOVERY BY 00Z.
BETWEEN 00-06Z, STRONG HEIGHT FALLS WILL SPREAD ACROSS THE GREAT
LAKES ELICITING A STRONG LLJ RESPONSE AND IMPRESSIVE MEAN WIND
THROUGH THE LOWER ATMOSPHERE. ASSUMING THE ABSENCE OF STABILIZING
EFFECTS OF EARLIER ACTIVITY, CONVECTIVE INITIATION ALONG THE
INTENSIFYING SURFACE TROUGH WOULD HAVE POTENTIAL TO GROW UPSCALE AND
PROPAGATE INTO AN ENVIRONMENT CHARACTERIZED BY 0-1KM BULK SHEAR
AROUND 40KTS, H7-H5 LAPSE RATES IN EXCESS OF 7.5C/KM, AND 0-1KM
MLCAPE OF 1500 TO 2000 J/KG. THREAT WOULD THEN DIMINISH FROM TOWARD
THE FAR SOUTHEAST AS CONVECTION ENCOUNTERS COMBINATION OF
INCREASINGLY CAPPED MID-LEVELS AND NOCTURNAL STABILIZATION.
LONG TERM...
UPPER LEVEL TROUGH AXIS (EXTENDING FROM LARGE UPPER LEVEL LOW
CENTERED OVER NORTHERN ONTARIO) WILL BE IN PLACE ON MONDAY OVER THE
CENTRAL GREAT LAKES...WITH COLD 500 MB TEMPS AROUND -14 C. THE MAIN
SURFACE COLD FRONT SHOULD CLEAR SOUTHERN MICHIGAN SHORTLY AFTER
12Z...AND SOUTHEAST MICHIGAN WILL BEGIN TO DRY OUT WITH SLOWLY
FALLING DEW PTS. HOWEVER...THERE STILL COULD BE JUST ENOUGH RESIDUAL
LOW LEVEL MOISTURE AROUND TO GENERATE SUFFICIENT INSTABILITY TO POP
ISOLATED-SCATTERED SHOWERS AND MAYBE A THUNDERSTORM...AS THERE IS
ALSO A SECONDARILY COLD FRONT WHICH LOOKS TO BE DROPPING SOUTH FROM
NORTHERN LOWER MICHIGAN...PROVIDING THE BETTER FOCUS. 850 MB TEMPS
STILL IN THE LOWER TEENS ON MONDAY...ALLOWING FOR MAXES AROUND 80
DEGREES...WILL FALL INTO THE UPPER SINGLE NUMBERS TO AROUND 10 C BY
TUESDAY...WHICH SHOULD RESULT IN MAXES HOLDING IN THE MID/UPPER 70S.
A SPOKE OF UPPER LEVEL ENERGY IS FORECASTED TO SWING THROUGH
NORTHERN LOWER MICHIGAN DURING TUESDAY..COUPLED WITH THE DAYTIME
INSTABILITY COULD TOUCH OF A FEW SHOWERS NORTH OF I-69...OTHERWISE
UPPER LEVEL NORTHWEST CONFLUENT FLOW/GENERAL SUBSIDENCE REGIME LOOKS
TO PERSIST AT LEAST INTO WEDNESDAY...SUPPORTING SLOWLY STRENGTHENING
HIGH PRESSURE OVER LOWER MICHIGAN...PROVIDING FAVORABLE RADIATING
NIGHTTIME CONDITIONS ALLOWING MINS TO FALL INTO THE LOW/MID
50S...WITH HIGHS STILL STUCK IN THE 70S FOR WEDNESDAY.
MARINE...
SOUTHWEST WINDS WILL BE INCREASING TODAY AHEAD OF A COLD
FRONT...WITH 25 KNOT GUSTS EXPECTED ACROSS ALL NEARSHORE
WATERS...AND SMALL CRAFT ADVISORIES WILL CONTINUE. COLD FRONT
ARRIVING TONIGHT LOOKS TO TRIGGER THUNDERSTORMS...WHICH COULD BE
SEVERE...PRODUCING WINDS OF 50 KNOTS. WINDS WILL TURN WEST AND THEN
NORTHWEST BEHIND THE FRONT DURING MONDAY. WIND SPEEDS MONDAY LOOK TO
BE GREATEST OVER NORTHERN LAKE HURON...WHERE THEY WILL REACH BETWEEN
15 TO 25 KNOTS MONDAY NIGHT THROUGH TUESDAY NIGHT AS COOLER AIR
SETTLES OVER THE CENTRAL GREAT LAKES REGION. THERE WILL BE A CHANCE
OF SHOWERS AND ISOLATED THUNDERSTORMS OVER LAKE HURON DURING THIS
TIME FRAME AS WELL.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT UNTIL 10 PM EDT THIS EVENING FOR MIZ049.
LAKE HURON...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LHZ421-422-441>443.
LAKE ST CLAIR...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LCZ460.
MICHIGAN WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT MONDAY FOR LEZ444.
&&
$$
AVIATION.....DG
UPDATE.......DG
SHORT TERM...JVC
LONG TERM....SF
MARINE.......SF
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
229 PM CDT SUN AUG 2 2015
.SHORT TERM: (THROUGH THIS EVENING)
ISSUED AT 226 PM CDT SUN AUG 2 2015
CU FIELD IS GETTING A LITTLE MORE AGITATED ACROSS EASTERN MISSOURI
AND SOUTHWEST ILLINOIS AND THE HRRR CONTINUES TO SHOW THE POTENTIAL
OF SOME PULSE STORMS...SO HAVE INCLUDED SOME SLIGHT CHANCE/ISOLATED
POPS FOR LATE THIS AFTERNOON INTO THIS EVENING FOR THIS AREA.
OTHERWISE...ITS HOT OUTSIDE WITH TEMPERATURES IN THE MIDDLE 90S AND
HEAT INDICES CLOSING IN ON THE CENTURY MARK IN SOME LOCALS.
CVKING
.LONG TERM: (MONDAY THROUGH NEXT SUNDAY)
ISSUED AT 226 PM CDT SUN AUG 2 2015
COLD FRONT CURRENTLY LOCATED ACROSS THE UPPER MIDWEST WILL DROP
SOUTH INTO THE CWA LATE TONIGHT...REACHING THE INTERSTATE 70
CORRIDOR BY DAYBREAK TOMORROW. LITTLE OR NO UPPER LEVEL SUPPORT AND
MEAGER SURFACE CONVERGENCE WILL KEEPS POPS IN THE SLIGHT CHANCE
CATEGORY OVERNIGHT AND NOT MENTIONABLE TOMORROW MORNING. DAYTIME
HEATING TOMORROW AFTERNOON SHOULD RESULT IN AT LEAST ISOLATED
CONVECTION NEAR THE STALLED FRONT BUT BETTER CHANCES OF RAIN WILL
PROBABLY HOLD OFF UNTIL LATE MONDAY NIGHT AND TUESDAY WHEN MODEL
GUIDANCE IS SHOWING MOISTURE CONVERGENCE DEVELOPING NORTH OF THE
FRONT FROM NORTH CENTRAL MISSOURI TO SOUTHWEST ILLINOIS. HAVE
INCREASED POPS SLIGHTLY FOR THIS TIME PERIOD BUT ANTICIPATE
FURTHER ADJUSTMENTS WILL BE NEEDED.
THUNDERSTORM CHANCES CONTINUE MUCH OF THE WEEK AS THE QUASI-
STATIONARY FRONT WILL INTERACT WITH SEVERAL UPPER LEVEL DISTURBANCES
AND THE NOCTURNAL LOW LEVEL JET. TEMPERATURES TO REMAIN BELOW
NORMAL WITH CLOUDS AND RAIN CHANCES.
HIGH PRESSURE WILL FINALLY MOVE INTO THE AREA FOR THE WEEKEND WITH
BELOW NORMAL TEMPERATURES CONTINUING.
CVKING
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1240 PM CDT SUN AUG 2 2015
SPECIFICS FOR KUIN, KCOU: WINDS WILL REMAIN SOUTHWESTERLY TO
WEST-SOUTHWESTERLY AROUND THE BACK SIDE OF A HIGH PRESSURE CENTER
UNTIL AN APPROACHING COLD FRONT GETS CLOSER TO THE TERMINALS.
WINDS WILL BECOME WESTERLY JUST AHEAD OF AND ALONG THE FRONT, THEN
TURN NORTHERLY AFTER FROPA OCCURS (17-21Z AT KCOU AND 10-14Z AT
KUIN). ISOLATED TO SCATTERED SH/TS ARE POSSIBLE THIS AFTERNOON,
HOWEVER PCPN CHANCES ARE HIGHER TOMORROW AFTN AT KCOU INVOF THE
COLD FRONT.
SPECIFICS FOR KSTL, KSUS, KCPS: WINDS WILL REMAIN SOUTHWESTERLY TO
WEST-SOUTHWESTERLY AROUND THE BACK SIDE OF A HIGH PRESSURE CENTER
UNTIL A COLD FRONT APPROACHES AFTER 03/06Z. WINDS WILL SLOWLY
BECOME WESTERLY AS THE FRONT APPROACHES, THEN TURN NORTHWESTERLY
TO NORTHERLY AFTER FROPA OCCURS BETWEEN 17-21Z. ISOLATED TO
SCATTERED SH/TS ARE POSSIBLE THIS AFTERNOON, HOWEVER PCPN CHANCES
ARE HIGHER TOMORROW AFTERNOON INVOF THE COLD FRONT.
KANOFSKY
&&
.PRELIMINARY POINT TEMPS/POPS:
SAINT LOUIS 77 90 74 87 / 20 20 40 30
QUINCY 68 84 65 82 / 20 10 30 30
COLUMBIA 69 89 70 86 / 10 20 20 40
JEFFERSON CITY 71 91 71 87 / 10 20 20 30
SALEM 71 88 67 85 / 20 20 20 30
FARMINGTON 72 91 72 88 / 20 20 20 30
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1248 PM CDT SUN AUG 2 2015
.SHORT TERM: (THROUGH LATE THIS AFTERNOON)
ISSUED AT 455 AM CDT SUN AUG 2 2015
THUNDERSTORMS HAVE DEVELOPED EARLY THIS MORNING OVER SOUTH CENTRAL
IOWA IN AN AREA OF LOW LEVEL MOISTURE CONVERGENCE ON THE NOSE OF A
30KT LOW LEVEL JET. RAP SHOWS THAT THIS LOW LEVEL CONVERGENCE WILL
MOVE ACROSS THE NORTHERN PART OF THE CWA THIS MORNING. WILL KEEP
ISOLATED THUNDERSTORMS GOING OVER THIS AREA THROUGH AT LEAST THE
MORNING HOURS.
WENT WITH A BLEND OF THE MOS GUIDANCE FOR HIGHS TODAY WHICH IS
SUPPORTED BY MIXING DOWN THE 850MB TEMPERATURES.
BRITT
.LONG TERM: (TONIGHT THROUGH SATURDAY)
ISSUED AT 455 AM CDT SUN AUG 2 2015
(TONIGHT THROUGH TUESDAY)
COLD FRONT WILL MOVE DOWN INTO THE AREA TONIGHT AHEAD OF A WEAK
SHORTWAVE IN NORTHWESTERLY FLOW ALOFT. STILL EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP IN THE WEAK MOISTURE CONVERGENCE ALONG
THE COLD FRONT IN AREAS ALONG AND NORTH OF I-70. ISOLATED
THUNDERSTORMS WILL CONTINUE INTO MONDAY OVER THE SOUTHERN HALF OF
THE CWA AS THE COLD FRONT SHIFTS TO THE SOUTH. CHANCES FOR STORMS
WILL INCREASE MONDAY NIGHT INTO TUESDAY NIGHT AS THE FRONT STALLS
OVER THE AREA AS STRONGER SHORTWAVE TROUGH MOVES ACROSS THE AREA.
(WEDNESDAY THROUGH SATURDAY)
THE CHANCE OF THUNDERSTORMS WILL CONTINUE OVER THE AREA THROUGH
FRIDAY AS THE FRONT WILL REMAINED STALLED MISSOURI AND ILLINOIS.
BOTH THE ECMWF AND GFS ARE SHOWING A SERIES OF SHORTWAVES MOVING
OVER THE STALLED FRONT DURING THIS PERIOD. HIGH PRESSURE WILL
FINALLY MOVE INTO THE AREA BY SATURDAY PROVIDING A DRY DAY. WENT
WITH BELOW TEMPERATURES BECAUSE OF EXPECTED CLOUDS AND RAIN CHANCES.
BRITT
&&
.AVIATION: (FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1240 PM CDT SUN AUG 2 2015
SPECIFICS FOR KUIN, KCOU: WINDS WILL REMAIN SOUTHWESTERLY TO
WEST-SOUTHWESTERLY AROUND THE BACK SIDE OF A HIGH PRESSURE CENTER
UNTIL AN APPROACHING COLD FRONT GETS CLOSER TO THE TERMINALS.
WINDS WILL BECOME WESTERLY JUST AHEAD OF AND ALONG THE FRONT, THEN
TURN NORTHERLY AFTER FROPA OCCURS (17-21Z AT KCOU AND 10-14Z AT
KUIN). ISOLATED TO SCATTERED SH/TS ARE POSSIBLE THIS AFTERNOON,
HOWEVER PCPN CHANCES ARE HIGHER TOMORROW AFTN AT KCOU INVOF THE
COLD FRONT.
SPECIFICS FOR KSTL, KSUS, KCPS: WINDS WILL REMAIN SOUTHWESTERLY TO
WEST-SOUTHWESTERLY AROUND THE BACK SIDE OF A HIGH PRESSURE CENTER
UNTIL A COLD FRONT APPROACHES AFTER 03/06Z. WINDS WILL SLOWLY
BECOME WESTERLY AS THE FRONT APPROACHES, THEN TURN NORTHWESTERLY
TO NORTHERLY AFTER FROPA OCCURS BETWEEN 17-21Z. ISOLATED TO
SCATTERED SH/TS ARE POSSIBLE THIS AFTERNOON, HOWEVER PCPN CHANCES
ARE HIGHER TOMORROW AFTERNOON INVOF THE COLD FRONT.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
421 PM CDT SUN AUG 2 2015
.SYNOPSIS...
ISSUED AT 419 PM CDT SUN AUG 2 2015
STALLED BOUNDARY STRETCHED EAST WEST ACROSS CENTRAL NEBRASKA THIS
AFTERNOON. WARM MOIST ARE SOUTH OF THE BOUNDARY COMBINING WITH SHEAR
OF 30 TO 40 KTS AND CAPE OF AROUND 2000 J/KG TO PRODUCE SCATTERED
THUNDERSTORMS. UPPER LEVEL RIDGE REMAINS ACROSS SOUTHWEST CONUS WITH
NORTHWEST FLOW ACROSS THE HIGH PLAINS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 419 PM CDT SUN AUG 2 2015
ISOLATED TO SCATTERED THUNDERSTORMS CONTINUE TO DEVELOP ALONG AND
SOUTH OF A STALLED MID LEVEL FRONT. MOISTURE IS DECENT AND SHEAR IS
MARGINAL BUT ENOUGH FOR A FEW STRONG THUNDERSTORMS THIS EVENING.
STORMS WILL DRIFT SOUTHEAST AND EXPECT THEM TO DIMINISH AFTER
SUNSET. OVERNIGHT A WAVE WILL MOVE ACROSS NORTHERN NEBRASKA AND THE
LATEST RAP BRINGS SOME QPF THROUGH THE REGION. THIS ACTIVITY MAY
KEEP TEMPS UP...HOWEVER EXPECT SHOWERS TO BE SCT TO ISOLD WITH
BREAKS TO ALLOW FOR TEMPS TO COOL DOWN AND WENT WITH GUIDANCE.
TOMORROW COOLER CONDITIONS WITH HIGHS IN THE 80S TO LOWER 90S.
ANOTHER DISTURBANCE WILL BRING ADDITIONAL CHANCES FOR ISOLATED
THUNDERSTORMS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 419 PM CDT SUN AUG 2 2015
FORECAST CHALLENGES IN THE DAYS 2 AND 3 PERIOD INVOLVE PRECIPITATION
CHANCES ASSOCIATED WITH THE WEAK SWD ADVANCING FRONT CURRENTLY WHICH
STALLS AND RETREATS SLOWLY NWD THROUGH THIS PERIOD. UPPER PATTERN
INFLUENCED BY UPPER LOW OVER HUDSON BAY WITH AN UPPER JET AND
ASSOCIATED PV ANOMALIES MOVING ACROSS THE UPPER MIDWEST AND GREAT
LAKES AREA. AS THE JET ROUNDS THE BASE OF THE UPPER LOW...UPPER
FORCING WANES AND TRANSITIONS EWD AND SFC HIGH SLIDES SEWD.
MEANWHILE SIGNIFICANT LEAD PV ANOMALY ASSOCIATED WITH AN UPPER
TROUGH OFF THE CA COAST WILL MOVE ACROSS THE CENTRAL ROCKIES
CONTINUING ITS NEG TILT. AS THIS OCCURS SFC TROUGHING WILL DEVELOP
ALONG THE LEE OF THE ROCKIES ALLOWING A RETURN TO STRONG SRLY LOW
LEVEL FLOW WHICH PUSHES THE BOUNDARY NWD THROUGH TUESDAY NIGHT. THIS
LEAD PV ANOMALY WILL ENTER THE HIGH PLAINS MONDAY INTO TUES THOUGH
THE MODELS DIFF SIGNIFICANTLY ON TIMING AND EVENTUAL LOCATION. THIS
WILL OBVIOUSLY HAVE AN IMPACT ON WHERE LOW LEVEL CONVERGENCE CAN
MAXIMIZE ALONG THE RETREATING FRONT. SO CONFIDENCE ON TIMING IS ONLY
AVERAGE...HOWEVER SERLY FLOW LEVEL FLOW INITIALLY WILL BRING
ADDITONIAL MOISTURE BACK INTO THE AREA WITH MUCH BETTER LARGE SCALE
FORCING SHOULD SEE BETTER PRECIP CHANCES MONDAY NIGHT INTO TUESDAY
THAN OF LATE.
FOR THURSDAY THROUGH THE WEEKEND...DEEPENING LOW PRESSURE NEAR THE
ALEUTIAN ISLANDS AND DOWNSTREAM TROUGHING ALONG THE PAC NW WILL
FLATTEN THE TRANSITORY CENTRAL PLAINS RIDGE LEADING TO QUASI-ZONAL
FLOW ACROSS WESTERN AND NORTH CENTRAL NEB. THIS WILL BE ASSOCIATED
WITH QUICKER MOVING SUBTLE PV ANOMALIES /SHORT WAVES/ HELPING TO
GENERATE THUNDERSTORMS ALONG PRE-EXISTING BOUNDARIES...AND GENERALLY
DIURNALLY DRIVEN INTO THE WEEKEND. TEMPERATURES IN THIS TYPE OF
PATTERN WILL TYPICALLY BE MODERATE AND GENERALLY AT OR SLIGHTLY
BELOW AVERAGE FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 115 PM CDT SUN AUG 2 2015
WEAK ELEVATED FRONTAL BOUNDARY DRIFTING SOUTH ACROSS THE HEART OF
THE CWA THIS AFTERNOON. SOME MID LEVEL CU AND EVEN A FEW SHOWERS
HAVE DEVELOPED EARLY THIS AFTERNOON. EXPECTED THESE SHOWERS TO
CONTINUE TO EXPAND IN COVERAGE AND MOVE SOUTH. ALL THE ACTIVITY
WILL REMAIN SOUTH OF KVTN WITH VFR CONDITIONS EXPECTED. FURTHER
SOUTH...IMPACTING SOUTHWESTERN NEBRASKA...INCLUDING KLBF...WILL BE
ISOLD TO SCT SHOWERS AND THUNDERSTORMS. DIRECT IMPACT AT THE KLBF
TERMINAL DIFFICULT TO PIN POINT AND WILL CONTINUE THE VCTS FOR
THIS AFTERNOON AND AMEND IF A STORM APPEARS TO MOVE OVER THE
TERMINAL. AFTER MIDNIGHT THE STORMS SHOULD BE EXITING/DIMINISHING.
GENERALLY VFR CONDITIONS EXPECTED...ALTHOUGH BRIEF MVFR/IFR
CONDITIONS IN AND NEAR STRONG THUNDERSTORMS WILL BE POSSIBLE.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MASEK
SHORT TERM...MASEK
LONG TERM...JWS
AVIATION...MASEK
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1218 PM CDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1211 PM CDT SUN AUG 2 2015
BUMPED UP DEWPOINTS A COUPLE OF DEGREES ALONG/SOUTH OF
I80...ESPECIALLY IN KNOWN AREAS WHERE DEWPOINTS WILL REMAIN
ELEVATED. THIS RESULTS IN HEAT INDEX VALUES 100-104 IN SOME SPOTS
THIS AFTERNOON ALONG/SOUTH OF I80. HAVE ADDED MENTION TO THE HWO
FOR NOW.
COLD FRONT IS A LITTLE SLOWER TO MOVE INTO THE REGION. HIRES
MODEL SUITES OF HRRR/NMM/ARW CONTINUE TO INDICATE POTENTIAL
CONVECTIVE DEVELOPMENT BY 19-21Z...PERHAPS IN THE PLATTE RIVER
VALLEY. EXTREME INSTABILITY HAS ALREADY DEVELOPED WITH SPC
MESOANALYSIS INDICATING AROUND 4000 J/KG OF CAPE. WIND SHEAR WILL
ALSO BE IN THE 30 KNOT RANGE...WHICH SHOULD BE SUPPORTIVE OF SOME
LARGE HAIL IF STORMS DEVELOP. BECAUSE OF THE EXTREME
INSTABILITY...WILL HAVE TO WATCH FOR MICROBURSTS TOO WITH
DOWNDRAFT CAPES PUSHING 1700-1900. WILL MAINTAIN A 20 PERCENT
CHANCE FOR NOW UNTIL WE SEE DEVELOPMENT.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
CHANCE FOR THUNDERSTORMS AND WARM TEMPERATURES TODAY...THEN OFF AND
ON STORM CHANCES THROUGH TUESDAY...ARE THE PRIMARY FORECAST CONCERNS.
SCATTERED THUNDERSTORMS POPPED UP EARLY THIS MORNING JUST AHEAD OF
MID LEVEL WAVE DROPPING SOUTHEAST THROUGH EASTERN NEBRASKA AND
SOUTHWEST IOWA AS PER WATER VAPOR AND RAP ANALYSIS. THIS WAVE WILL
TRACK EAST OF OUR CWA EARLY IN THE DAYLIGHT HOURS...WITH SUBSIDENCE
BEHIND WAVE KEEPING MUCH OF THE REST OF THE MORNING DRY.
ANOTHER SHORTWAVE IN THE NORTHERN PLAINS INTO THE NORTHERN GREAT
LAKES IS FORECAST TO SWEEP SOUTHEAST LATER TODAY...WITH SURFACE
REFLECTION IN THE FORM OF A FRONT/WIND SHIFT SETTLING INTO NORTHEAST
NEBRASKA THIS AFTERNOON. SURFACE DEW POINTS NEAR OR ABOVE 70F AHEAD
OF THIS BOUNDARY ARE EXPECTED TO POOL IN EASTERN NEBRASKA AND
WESTERN IOWA DURING PEAK HEATING. CONVERGENCE ALONG BOUNDARY SHOULD
BE ENOUGH TO GET AT LEAST ISOLATED THUNDERSTORMS FIRING IN UNSTABLE
ATMOSPHERE CHARACTERIZED BY MUCAPES OVER 2500 J/KG. MEANWHILE
MODERATE MID LEVEL FLOW WILL HELP GENERATE NEAR 40KT OF BULK SHEAR
WITH VECTORS NORMAL TO SURFACE CONVERGENCE...SUGGESTING DISCRETE AND
ROTATING STORMS ARE LIKELY...SUPPORTING HAIL AND WIND POTENTIAL.
ONLY MARGINAL RISK IN SPC OUTLOOK...AND CAN NOT ARGUE GIVEN
EXPECTED SCANT COVERAGE. INITIATION LOOKS TO BE FARTHER NORTH THAN
PREVIOUS MODEL RUNS WITH LATER ARRIVAL OF FRONT...MOSTLY LIKELY
FIRING NEAR OR SOUTH OF A WAYNE TO ALBION LINE BETWEEN 3 AND 4 PM.
EXPECT ISOLATED TO SCATTERED STORMS TO PROGRESS SOUTH THROUGH THE
REST OF THE AFTERNOON INTO THE EVENING WITH FRONTAL BOUNDARY
BEFORE EXITING SOUTHEAST NEBRASKA AND SOUTHWEST AROUND MIDNIGHT
WHEN LAST OF 850 MOISTURE PLUME FINALLY DROPS SOUTH.
AHEAD OF FRONT...TEMPERATURES ARE EXPECTED WELL INTO THE 90S
ESPECIALLY IF CLOUD COVER FROM MORNING CONVECTION DISSIPATES AS
EXPECTED. WILL LIKELY SEE SOME HEAT INDICES TOPPING 100 FOR A COUPLE
OF HOURS THIS AFTERNOON.
SHOULD SEE A DRY PERIOD AFTER MIDNIGHT TONIGHT...BUT LOWERING
PRESSURES IN THE HIGH PLAINS WILL DRAW 850 MOISTURE BACK NORTH
RATHER QUICKLY BY LATER MONDAY MORNING AS NORTHWEST MID LEVEL FLOW
CONTINUES. WILL KEEP OUR SMALL POPS FOR OUR WESTERN CWA DURING THAT
TIME PERIOD...WITH CHANCES/COVERAGE GRADUALLY INCREASING MONDAY
AFTERNOON...BUT ESPECIALLY OVERNIGHT AND TUESDAY AS MAGNITUDE OF
MOISTURE RETURN INCREASES. WILL MAINTAIN 30 TO 50 PERCENT STORM
CHANCES DURING THE DAY TUESDAY. SEVERE THREAT SHOULD BE MINIMAL THEN
AS INSTABILITY REMAINS WEAK DUE TO MUCH COOLER SURFACE
TEMPERATURES.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 354 AM CDT SUN AUG 2 2015
UNSETTLED WEATHER PATTERN WITH OCCASIONAL RAIN/STORM CHANCES WILL
CONTINUE THROUGH MUCH OF THE REST OF THE WEEK. MID LEVEL RIDGE IS
FORECAST TO REMAIN FROM TEXAS WEST TO THE SOUTHWESTERN STATES AT
LEAST THROUGH THURSDAY...KEEPING STORM TRACK ROLLING FROM THE
CENTRAL/NORTHERN ROCKIES ACROSS THE PLAINS. SEVERAL SHORTWAVES COULD
TRIGGER CONVECTION AT JUST ABOUT ANY TIME...WITH MORE POTENT WAVES
MOVING THROUGH OUR AREA WEDNESDAY DURING THE DAY AND THURSDAY
NIGHT AS PER ECMWF/GFS. WE SHOULD REMAIN ON THE COOL SIDE OF
SURFACE FRONTAL SYSTEM...SO INSTABILITY PROGS SUGGEST SEVERE
CHANCE WILL BE MINIMAL OVERALL WITH TEMPERATURES REMAINING IN THE
70S AND 80S MUCH OF THE WEEK.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1211 PM CDT SUN AUG 2 2015
VFR CONDITIONS THROUGH THE PERIOD AS A COLD FRONT MOVES INTO THE
AREA. THERE IS A 20 PERCENT CHANCE THAT STORMS COULD DEVELOP BY
19-21Z. THESE STORMS WOULD LIKELY BE SOUTH OF THE KOFK TAF
SITE...BUT COULD AFFECT KLNK/KOMA 23-01Z TIME FRAME. BECAUSE OF
LOW CERTAINTY ON DEVELOPMENT...WILL KEEP OUT OF THE TAF FOR
NOW...BUT WILL UPDATE FORECAST IF STORMS INDEED DEVELOP AND WOULD
AFFECT THOSE TAF SITES. WIND SHIFT WILL ALSO BE AFFECTING
KOMA/KLNK FROM SOUTHWEST TO NORTHWEST BY 23-01Z AS WELL.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
UPDATE...DEWALD
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1257 PM EDT SUN AUG 2 2015
.SYNOPSIS...
A STATIONARY FRONT LINGERING ALONG THE COAST OF THE SOUTHEAST
STATES WILL DISSIPATE MONDAY. THE NEXT FRONT WILL AFFECT THE AREA
LATE THIS WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 1250 PM SUNDAY...SEA BREEZE SLOWLY WORKING ITS WAY INLAND
AND A COUPLE OF SHOWERS HAVE FORMED OVER DOWNEAST CARTERET COUNTY.
PER LATEST HRRR AND NCAR ENSEMBLE WRF...THINK PRECIPITATION WILL
BE ISOLATED THROUGH THE BALANCE OF THE AFTERNOON AND EVENING AND
WILL KEEP ONLY A SLIGHT CHC POP OVER MAINLY THE SOUTHEASTERN HALF
OF THE CWA. TEMPERATURES ALREADY INTO THE LOWER 90S IN MANY SPOTS
AND CURRENT FORECAST IN GOOD SHAPE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/...
AS OF 3 AM SUN...BOTH MODELS INCREASE MOISTURE FROM THE SOUTH IN
RESPONSE TO BROAD UPPER TROF ALONG EASTERN SEABOARD SHARPENING UP.
WILL NUDGE POPS A BIT FURTHER NORTH AND INCREASE TO CHANCE SOUTH
OF A LINE FROM OREGON INLET TO MOREHEAD CITY.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 3 AM SUN...GFS/ECMWF TRENDING A BIT WETTER COAST MON INTO
MON NIGHT AS MOISTURE INCREASES AHEAD OF WEAK LOW LIFTING NE ALONG
REMNANT FRONTAL BOUNDARY. FOR NOW KEPT POPS IN CHC RANGE CST BUT
IF CURRENT MDL TRENDS CONT THEY MAY NEED TO BE INCREASED IN LATER
FCSTS. DEEP INLAND LOOKS MAINLY DRY AS BEST MOISTURE STAYS ALONG
THE CST. HIGHS MON LOWER 90S INLAND TO 80S CST WITH 70S AREAS WIDE
MON NIGHT.
MAIN STORY FOR THE TUE AND WED WILL BE THE HEAT AS TYPICAL
SUMMERTIME PATTERN RE-DEVELOPS WITH HIGH PRESSURE OFFSHORE AND
STRENGTHENING TROUGH INLAND. HEIGHTS BUILD THROUGH MID WEEK...WITH
LOW LEVEL THICKNESS VALUES AND 850MB TEMPS SUPPORTING HIGHS IN THE
UPPER 80S/LOW 90S ALONG THE COAST...AND MID 90S/POSSIBLY A FEW
UPPER 90S INLAND. FOR NOW FCST DEWPTS KEEP APPARENT TEMPS BELOW
105 BUT WILL BE CLOSE TO HEAT ADVRY. MAINLY SLIGHT CHC POPS TUE
AND WED WITH BEST CHC CST EARLY MORN AND INLAND DURING AFTN AND
EVENING.
CHANCE OF SHRA AND TSRA INCREASE LATE WEEK AS UPR TRF DEVELOPS TO
THE W WITH WEAK COLD FRONT APPROACHING FROM THE NW THU AND STALLING
NEAR THE AREA FRI INTO SAT. HAVE CHC POPS THRU THE PERIOD. WILL
REMAIN MUGGY HOWEVER TEMPS WONT BE QUITE A S HOT WITH MAINLY UPR 80S
AND LOWER 90S.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 1255 PM SUNDAY...PRETTY MUCH A PERSISTENCE FORECAST FOR
AVIATION THIS TAF CYCLE. SHOULD SEE A FEW CUMULUS ONLY THE SEA
BREEZE WITH ISOLATED CONVECTION POSSIBLE AT KEWN AND KOAJ. WITH
INCREASING DEWPOINTS TONIGHT...WILL AGAIN SEE PATCHY AREAS OF
IFR/MVFR FOG IN THE PREDAWN HOURS ON MONDAY.
LONG TERM /MON THROUGH THURSDAY/... AS OF 3 AM SUN...DECENT CVRG
OF SHRA/TSRA NEAR CST MON INTO MON NIGHT BUT BEST BET FOR REDUCED
CIGS/VSBYS WILL BE MAINLY E OF TERMINALS ESPCLY ISO/PGV WITH POSS
SOME MVFR OAJ/EWN. MAINLY VFR TUE AND WED WITH LIMITED PRECIP AND
LOW LVL SW FLOW LIMITING FOG/ST THREAT. COULD SEE BETTER CVRG OF
SHRA AND TSRA THU AHEAD OF NEXT FRONT WITH BRIEF SUB VFR POSS
MAINLY IN THE AFTN.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/
AS OF 1255 PM SUNDAY...WINDS STARTING TO PROCESS OF VEERING AROUND
TO THE SE/S AT THE BUOY SITES AND ON THE SOUNDS. WINDS SPEEDS ARE
UNIFORMLY 10 KNOTS OR LESS WITH SEAS IN THE 2 TO 3 FOOT RANGE WITH
A BIT OF SOME LONG PERIOD SWELL OVER THE NORTHERN WATERS. WINDS
BECOME MORE S/SW TONIGHT WITH SOME INCREASE TO 10 TO 15 KNOTS OVER
THE SOUTHERN WATERS BY MORNING.
LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 3 AM SUN...SSW WINDS WILL INCREASE MON AS WEAK LOW LIFTS NE
ALONG FRONT/TRF INLAND TIGHTENING GRDNT. WINDS SHLD REACH 15 TO 20
KTS MOST WTRS MON AFTN WITH SEAS BUILDING TO 4 TO 6 FEET HIGHEST
OUTER CNTRL AND SRN WTRS. SSW WINDS THEN EXPECTED AT 10 TO 20 KTS
REST OF THE FCST PERIOD AS TRF CONTS INLAND WITH HIGH OFFSHORE.
THESE WINDS WILL KEEP SEAS ELEVATED ESPCLY OUTER WTRS FROM HAT S
WHERE WILL BE MAINLY 5 TO 6 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CTC
SHORT TERM...HSA
LONG TERM...RF
AVIATION...RF/CTC
MARINE...RF/CTC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1138 AM MDT SUN AUG 2 2015
.UPDATE...
ISSUED AT 1128 AM MDT SUN AUG 2 2015
THUNDERSTORMS HAVE DEVELOPED QUICKLY LATE THIS MORNING NEAR THE
LARAMIE RANGE...SO INCREASED POP TODAY ALONG AND EAST OF THE
LARAMIE RANGE WHERE SCATTERED COVERAGE IS POSSIBLE. THE
PROBABILITY OF SEVERE TSTORMS IS LOW TODAY...BUT STORM MOTION AND
THE POTENTIAL FOR HEAVY RAINFALL IS THE MAIN CONCERN. STORM MOTION
THIS MORNING IS ACTUALLY A SLOW DRIFT TOWARDS THE SOUTHWEST. IT
WILL BE INTERESTING TO SEE HOW THIS ACTIVITY EVOLVES THROUGH THE
DAY ONCE A FEW PERSISTENT OUTFLOW BOUNDARIES DEVELOP. MAY NEED TO
MONITOR THE POTENTIAL FOR FLASH FLOODING THIS AFTERNOON AND INTO
THIS EVENING.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY NIGHT)
ISSUED AT 300 AM MDT SUN AUG 2 2015
TODAY...FLOW ALOFT REMAINS NORTHWEST. LOOKS LIKE THE NAM PROJECTS A
LOW LEVEL BOUNDARY TO SET UP THIS AFTERNOON ALONG THE WYOMING AND
COLORADO STATE LINE WITH A NICE 850/700 MB THETA-E RIDGE AXIS OVER
NORTHERN COLORADO. THUS...AS NAM DEPICTS...EXPECT ISOLATED TO
SCATTERED THUNDERSTORMS TO DEVELOP ALONG AND NEAR THE COLORADO STATE
LINE...THEN SLOWLY DIMINISH THIS EVENING ALONG THE LARAMIE RANGE.
TONIGHT/MONDAY...MODELS CONSISTENT IN SHOWING MORE MONSOONAL
MOISTURE BEING TAPPED INTO AND MOVING ACROSS OUR COUNTIES MONDAY
AFTERNOON...THOUGH NOW FURTHER WEST THAN PREVIOUS RUNS INDICATED.
STILL THOUGH...WITH A SHORTWAVE TROUGH ALOFT MOVING OVERHEAD AND
INCREASING LOW AND MID LEVEL MOISTURE...WILL CONTINUE OUR FORECAST
WITH ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS ALONG
AND WEST OF INTERSTATE 25...WITH LESSER ACTIVITY FURTHER EAST.
MONDAY NIGHT/TUESDAY/TUESDAY NIGHT...SHORTWAVE TROUGH ALOFT MOVES
SLOWLY EASTWARD ACROSS OUR NORTHERN COUNTIES...AND WITH PLENTY OF
LOW AND MID LEVEL MOISTURE...WILL SEE SCATTERED SHOWERS AND
THUNDERSTORMS ACROSS OUR NORTHERN COUNTIES...LESS ACTIVITY FURTHER
SOUTH WITH DRIER AIRMASS AND NEGATIVE THETA-E ADVECTION.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 300 AM MDT SUN AUG 2 2015
MONSOONAL MOISTURE TO REMAIN OVER THE AREA THROUGH AT LEAST
THURSDAY. DEPENDING ON WHICH MEDIUM RANGE GUIDANCE USED...IT COULD
BE LONGER. FORECAST BASED OFF THE MORE MOIST ECMWF THIS FORECAST
CYCLE.
STARTING OFF WEDNESDAY...WE ARE LOOKING AT THE SEMI-PERMANENT
THATS BEEN IN THE AREA TO LAY ALONG THE NEBRASKA
PANHANDLE...MAYBE SLIGHTLY FURTHER EAST. GFS SHOWING THE BOUNDARY
FURTHER EAST AND THUS THE ENTIRE CWFA DRY. ECMWF ON THE OTHER HAND
HAS THE BOUNDARY REMAINING ALONG THE EAST SLOPES OF THE LARAMIE
RANGE...WITH NORTHEAST UPSLOPE FLOW ACROSS THE PANHANDLE. THIS
WOULD GIVE MOST LOCATIONS ALONG AND EAST OF THE LARAMIE RANGE WITH
AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS WEDNESDAY AFTERNOON.
THURSDAY AFTERNOON...A FAIRLY STRONG SHORTWAVE TRACKS ACROSS
NORTHERN WYOMING INTO SOUTH DAKOTA. STRONG SOUTH TO SOUTHEASTERLY
850MB WINDS IN THE PANHANDLE AND A 70KT 250MB JET COULD BE SETTING
US UP FOR ANOTHER ROUND OF SEVERE THUNDERSTORMS AT LEAST FOR THE
SOUTHERN HALF OF THE PANHANDLE AS WELL AS EASTERN LARAMIE
COUNTY...UP INTO GOSHEN COUNTY. SHOWERS AND THUNDERSTORMS LOOK TO
PERSIST INTO THE LATE EVENING HOURS THURSDAY.
AFTER A DRY FRIDAY WITH A TRANSITORY RIDGE MOVING THROUGH THE
CWFA...SATURDAY LOOKS TO BE A REPEAT OF THURSDAY AS ANOTHER
SHORTWAVE MOVES INTO THE AREA FROM THE SOUTHWEST. SHOULD SEE AT
LEAST SLIGHT CHANCE POPS FOR MUCH OF THE AREA WITH BEST CHANCES
ALONG THE WYOMING COLORADO STATE LINE.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 450 AM MDT SUN AUG 2 2015
LOOKS LIKE A REPEAT IN THE FORECAST FOR SOUTHEAST WYOMING AND
NEBRASKA PANHANDLE AIRPORTS AS WAS THE CASE SATURDAY. HRRR USED
FOR TIMING OF CONVECTION...MAINLY ALONG THE I-80 CORRIDOR FROM
KSNY TO KLAR. TIMING LOOKS TO BE FROM 20Z THROUGH 01Z.
&&
.FIRE WEATHER...
ISSUED AT 145 AM MDT SUN AUG 2 2015
HUMIDITIES INCREASING THE NEXT FEW DAYS AS LOW AND
MID LEVEL MOISTURE INCREASES ALONG WITH INCREASING CHANCES FOR LATE
DAY SHOWERS AND THUNDERSTORMS.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...TJT
SHORT TERM...RUBIN
LONG TERM...GCC
AVIATION...GCC
FIRE WEATHER...RUBIN