Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/03/13
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NWS LOS ANGELES/OXNARD CA
800 PM PDT THU MAY 2 2013
...GUSTY SANTA ANA WINDS AND EXTREME FIRE DANGER WILL CONTINUE
THROUGH FRIDAY...
...UPDATED FIRE WEATHER DISCUSSION...
.SYNOPSIS...
A HIGH PRESSURE SYSTEM WITH GUSTY OFFSHORE WINDS WILL CAUSE WELL
ABOVE NORMAL TEMPERATURES THROUGH FRIDAY. THE HIGH WILL EXIT THE
REGION LATE FRIDAY AND TEMPERATURES WILL DROP ON SATURDAY. A LOW
PRESSURE SYSTEM WILL ARRIVE BY SUNDAY WITH POSSIBLE PRECIPITATION
THROUGH TUESDAY. THE TEMPERATURES WILL BE BELOW NORMAL INTO MIDWEEK.
&&
.SHORT TERM (TODAY-SUN)...THE SMOKE PLUME FROM THE SPRINGS FIRE IN
CAMARILLO IS EXPECTED TO CONTINUE A WEST NORTHWEST TRAJECTORY
OVERNIGHT AND POSSIBLY MOVE OVER THE COASTAL WATERS ALONG THE
CENTRAL COAST. LOW LEVEL CLOUD FIELD APPROACHING THE CENTRAL COAST
THIS AFTERNOON WILL LIKELY MOVE ASHORE THIS EVENING AND THEN SCOUR
OUT OR MOVE OFFSHORE OVERNIGHT AS THE NORTHEAST WINDS DEVELOP. THE
LATE MORNING TEMPERATURES WILL LIKELY BE THE HIGHEST FOR THE DAY
WITH BEACH LOCATIONS...LIKE PISMO BEACH...POSSIBLY REACHING THE
LOWER 80S. AND CENTRAL COAST INLAND AREAS WILL LIKELY CLIMB TO
RECORD HEAT FRIDAY AFTERNOON. PATCHY LOW LEVEL CLOUDS SOUTH OF THE
NORTHERN CHANNEL ISLANDS WILL CONTINUE TO APPROACH THE LA/VENTURA
COASTS THROUGH THIS AFTERNOON AND POSSIBLY MOVE INTO THE SANTA
MONICA BAY WITH DENSE FOG TONIGHT. OTHERWISE THE LATEST HRRR WAS
CONSISTENT WITH PREVIOUS RUNS AND ONSHORE WINDS WILL MOVE INTO THE
COASTAL VALLEYS WHILE THE STRONG NORTHEAST WINDS DIMINISH THROUGH
THE REMAINDER OF THIS AFTERNOON. THE NORTHEAST WINDS WILL LIKELY
PREVAIL INLAND OVERNIGHT AND AS THE SEABREEZE DISSIPATES THE
NORTHEAST WINDS WILL RETURN TO THE COAST. THE WINDS MAY STRENGTHEN
WITH GUSTS TO 45 MPH FRIDAY MORNING OVER THE HIGH COUNTRY WITH LOCAL
GUSTS TO 35 MPH IN THE INTERIOR COASTAL VALLEYS. A WIND ADVISORY MAY
BE ISSUED FOR THE HIGH COUNTRY FOLLOWING THE HIGH WIND WARNING
EXPIRATION AT 6 PM THIS EVENING. A COOLING TREND WILL OCCUR SATURDAY
THROUGH SUNDAY. ONSHORE WINDS WILL RETURN SATURDAY AND TEMPERATURES
WILL COOL THOUGH LIKELY REMAIN 5 TO 10 DEGREES ABOVE NORMAL SATURDAY
AND TO AT OR BELOW NORMAL SUNDAY. AN UPPER LEVEL LOW PRESSURE SYSTEM
CURRENTLY BETWEEN THE HAWAIIAN ISLANDS AND SOUTHERN CALIFORNIA WILL
APPROACH THROUGH SUNDAY. LATEST GUIDANCE DIFFERS FROM PREVIOUS RUNS
AND BETWEEN SUITES THOUGH SKIES WILL LIKELY BECOME CLOUDY AND A
CHANCE OF SHOWERS ARE EXPECTED SUNDAY.
.LONG TERM (MON-THU)...A STABLE TYPE PATTERN WITH A ANTICYCLONIC
CIRCULATION CENTERED OVER THE PAC NW AND CYCLONIC CIRCULATION OVER
THE SFO BAY AREA WILL DEVELOP SUNDAY AND PERSIST THROUGH WEDNESDAY.
ONE UPPER LEVEL TROUGH WILL ROTATE AND EXIT THROUGH THE SOLUTION TYPE
FEATURE SUNDAY THROUGH MONDAY AND A SECOND ONE IS EXPECTED TUESDAY
NIGHT THROUGH WEDNESDAY. PARTLY TO MOSTLY CLOUDY SKIES ARE EXPECTED
WITH A SLIGHT CHANCE OF SHOWERS MONDAY THROUGH LATE TUESDAY EVENING.
TEMPERATURES WILL COOL THROUGH THE PERIOD AND LIKELY RANGE 4 TO 8
DEGREES BELOW SEASONAL NORMAL THROUGH THE PERIOD.
&&
.FIRE WEATHER...
RED FLAG WARNINGS IN EFFECT FOR MUCH OF LOS ANGELES AND VENTURA
COUNTIES THROUGH FRIDAY AFTERNOON...WHERE EXTREME FIRE DANGER
EXISTS. AS OF 730 PM...ONSHORE WINDS HAVE SPREAD INTO MUCH OF THE
LOWER ELEVATIONS OF THE SPRINGS FIRE...HOWEVER CURRENT OBSERVATIONS
STILL INDICATE OFFSHORE CONDITIONS ACROSS HIGHER RIDGETOPS OF THE
BURN AREA. FURTHER INLAND...OFFSHORE WINDS AND BONE DRY CONDITIONS
REMAIN FIRMLY IN TACT...HOWEVER WIND SPEEDS ARE DOWN CONSIDERABLY
FROM EARLIER TODAY. THIS IS SOME OF THE DRIEST AIR WE HAVE SEEN IN
QUITE A WHILE ACROSS THE SOUTHLAND...WITH LONG DURATIONS OF SINGLE
DIGIT HUMIDITIES BEING OBSERVED. IN FACT...A FEW LOCATIONS HAVE
REPORTED RELATIVE HUMIDITIES AS LOW AS 1 PERCENT TODAY!
BETWEEN 10 AND 11 PM...WINDS ARE EXPECTED TO REVERSE TO AN OFFSHORE
DIRECTION ACROSS MUCH OF THE SPRINGS FIRE BURN AREA. AS OFFSHORE GRADIENTS
TIGHTEN SLIGHTLY OVERNIGHT INTO FRIDAY MORNING...THERE WILL BE A
SLIGHT INCREASE IN OFFSHORE WINDS. THE SANTA ANA WINDS WILL NOT BE
AS STRONG AS WE SAW TODAY...HOWEVER GUSTS IN THE 20 TO 30 MPH RANGE
CAN BE EXPECTED ACROSS THE BURN AREA BETWEEN 4 AM AND NOON FRIDAY...WITH
GUSTS AS HIGH AS 35 MPH AT RIDGETOP LEVEL. AS WINDS REVERSE TO OFFSHORE
LATER TONIGHT...LOOKING FOR HUMIDITIES TO ONCE AGAIN FALL INTO
SINGLE DIGITS ACROSS THE SPRINGS BURN AREA.
THE OFFSHORE FLOW WILL BRING ANOTHER ROUND OF HOT AND DRY CONDITIONS TO
THE REGION ON FRIDAY...WITH TEMPERATURES SOARING TO BETWEEN 90 AND 100
DEGREES ALONG WITH LONG DURATIONS OF SINGLE DIGIT HUMIDITIES. WINDS
ARE EXPECTED TO REVERSE TO ONSHORE EARLIER ON FRIDAY...MOST LIKELY
BETWEEN 1 AND 2 PM ACROSS THE SPRINGS BURN AREA. THE ONSHORE WINDS WILL
ALSO SPREAD FURTHER INLAND ACROSS MOST VALLEY AREAS LATER FRIDAY
AFTERNOON.
THE COMBINATION OF GUSTY OFFSHORE WINDS...LOW HUMIDITIES AND VERY
DRY FUELS HAS CREATED THE POTENTIAL FOR EXTREME FIRE BEHAVIOR. IT IS
IMPORTANT TO NOTE THAT FUEL CONDITIONS ARE EXTREMELY DRY FOR THIS
TIME OF THE YEAR...WITH VALUES THAT ARE MORE TYPICAL FOR JULY OR
AUGUST.
&&
.AVIATION...02/2350Z...GENERALLY HI CONFIDENCE IN THE CURRENT TAFS
WITH VFR CONDITIONS AT ALMOST ALL AIRFIELDS THROUGH FRI. EXCEPTION
IS KSMX WHERE THERE IS A 70 PERCENT CHANCE LOW CLOUDS AND IFR
CONDITIONS SHOULD MOVE INTO THE AIRFIELD BY 05Z THEN CLEAR TO VFR BY
12Z. THERE IS ALSO A 30 PERCENT CHANCE LIFR CONDITIONS COULD AFFECT
KSMX AT TIMES DURING THE PERIOD. GUSTY E WINDS AT KWJF AND KPMD WILL
DIMINISH EARLY THIS EVENING.
KLAX...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU FRI
EVENING.
KBUR...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU FRI.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
&&
$$
PUBLIC...30
AVIATION...SIRARD
SYNOPSIS...SETO
FIRE...GOMBERG
WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATE
NWS LOS ANGELES/OXNARD CA
450 PM PDT THU MAY 2 2013
***UPDATE FOR NEW AVIATION DISCUSSION***
.SYNOPSIS...
A HIGH PRESSURE SYSTEM WITH GUSTY OFFSHORE WINDS WILL CAUSE WELL
ABOVE NORMAL TEMPERATURES THROUGH FRIDAY. THE HIGH WILL EXIT THE
REGION LATE FRIDAY AND TEMPERATURES WILL DROP ON SATURDAY. A LOW
PRESSURE SYSTEM WILL ARRIVE BY SUNDAY WITH POSSIBLE PRECIPITATION
THROUGH TUESDAY. THE TEMPERATURES WILL BE BELOW NORMAL INTO MIDWEEK.
&&
.SHORT TERM (TODAY-SUN)...THE SMOKE PLUME FROM THE SPRINGS FIRE IN
CAMARILLO IS EXPECTED TO CONTINUE A WEST NORTHWEST TRAJECTORY
OVERNIGHT AND POSSIBLY MOVE OVER THE COASTAL WATERS ALONG THE
CENTRAL COAST. LOW LEVEL CLOUD FIELD APPROACHING THE CENTRAL COAST
THIS AFTERNOON WILL LIKELY MOVE ASHORE THIS EVENING AND THEN SCOUR
OUT OR MOVE OFFSHORE OVERNIGHT AS THE NORTHEAST WINDS DEVELOP. THE
LATE MORNING TEMPERATURES WILL LIKELY BE THE HIGHEST FOR THE DAY
WITH BEACH LOCATIONS...LIKE PISMO BEACH...POSSIBLY REACHING THE
LOWER 80S. AND CENTRAL COAST INLAND AREAS WILL LIKELY CLIMB TO
RECORD HEAT FRIDAY AFTERNOON. PATCHY LOW LEVEL CLOUDS SOUTH OF THE
NORTHERN CHANNEL ISLANDS WILL CONTINUE TO APPROACH THE LA/VENTURA
COASTS THROUGH THIS AFTERNOON AND POSSIBLY MOVE INTO THE SANTA
MONICA BAY WITH DENSE FOG TONIGHT. OTHERWISE THE LATEST HRRR WAS
CONSISTENT WITH PREVIOUS RUNS AND ONSHORE WINDS WILL MOVE INTO THE
COASTAL VALLEYS WHILE THE STRONG NORTHEAST WINDS DIMINISH THROUGH
THE REMAINDER OF THIS AFTERNOON. THE NORTHEAST WINDS WILL LIKELY
PREVAIL INLAND OVERNIGHT AND AS THE SEABREEZE DISSIPATES THE
NORTHEAST WINDS WILL RETURN TO THE COAST. THE WINDS MAY STRENGTHEN
WITH GUSTS TO 45 MPH FRIDAY MORNING OVER THE HIGH COUNTRY WITH LOCAL
GUSTS TO 35 MPH IN THE INTERIOR COASTAL VALLEYS. A WIND ADVISORY MAY
BE ISSUED FOR THE HIGH COUNTRY FOLLOWING THE HIGH WIND WARNING
EXPIRATION AT 6 PM THIS EVENING. A COOLING TREND WILL OCCUR SATURDAY
THROUGH SUNDAY. ONSHORE WINDS WILL RETURN SATURDAY AND TEMPERATURES
WILL COOL THOUGH LIKELY REMAIN 5 TO 10 DEGREES ABOVE NORMAL SATURDAY
AND TO AT OR BELOW NORMAL SUNDAY. AN UPPER LEVEL LOW PRESSURE SYSTEM
CURRENTLY BETWEEN THE HAWAIIAN ISLANDS AND SOUTHERN CALIFORNIA WILL
APPROACH THROUGH SUNDAY. LATEST GUIDANCE DIFFERS FROM PREVIOUS RUNS
AND BETWEEN SUITES THOUGH SKIES WILL LIKELY BECOME CLOUDY AND A
CHANCE OF SHOWERS ARE EXPECTED SUNDAY.
.LONG TERM (MON-THU)...A STABLE TYPE PATTERN WITH A ANTICYCLONIC
CIRCULATION CENTERED OVER THE PAC NW AND CYCLONIC CIRCULATION OVER
THE SFO BAY AREA WILL DEVELOP SUNDAY AND PERSIST THROUGH WEDNESDAY.
ONE UPPER LEVEL TROUGH WILL ROTATE AND EXIT THROUGH THE SOLITON TYPE
FEATURE SUNDAY THROUGH MONDAY AND A SECOND ONE IS EXPECTED TUESDAY
NIGHT THROUGH WEDNESDAY. PARTLY TO MOSTLY CLOUDY SKIES ARE EXPECTED
WITH A SLIGHT CHANCE OF SHOWERS MONDAY THROUGH LATE TUESDAY EVENING.
TEMPERATURES WILL COOL THROUGH THE PERIOD AND LIKELY RANGE 4 TO 8
DEGREES BELOW SEASONAL NORMAL THROUGH THE PERIOD.
&&
.FIRE WEATHER...
RED FLAG WARNINGS IN EFFECT FOR MUCH OF LOS ANGELES AND VENTURA
COUNTIES THROUGH FRIDAY AS A MODERATE TO STRONG SANTA ANA WIND EVENT
AFFECTS SOUTHWEST CALIFORNIA. THE PEAK IN WIND SPEEDS IS OCCURRING
THIS MORNING...WITH GUSTS OF 65 TO 75 MPH OVER THE INTERIOR PEAKS OF
LA COUNTY...AND VALLEY LOCATIONS SEEING GUSTS OF 40 TO 60
MPH...STRONGEST IN THE SANTA CLARITA VALLEY AND THE EASTERN VENTURA
VALLEYS. GUSTS TO 45 MPH HAVE BEEN OBSERVED AS FAR WEST AS THE
VENTURA COUNTY COAST NEAR CAMARILLO. RELATIVE HUMIDITIES ARE VERY
LOW WITH MANY VALUES IN THE MID TO LOWER SINGLE DIGITS OBSERVED
ACROSS THE AREA. IN ADDITION...FUELS IN THE AREA ARE EXTREMELY DRY
FOR THIS TIME OF THE YEAR...AT VALUES THAT ARE MORE TYPICAL FOR MID
TO LATE SUMMERTIME. THE COMBINATION OF STRONG WIND GUSTS...LOW
HUMIDITIES AND VERY DRY FUELS HAS CREATED THE POTENTIAL FOR EXTREME
FIRE BEHAVIOR.
SURFACE PRESSURE GRADIENTS ARE BEGINNING TO EASE SLIGHTLY ACROSS
THE AREA...WHICH SHOULD ALLOW THE OFFSHORE WINDS TO BEGIN TO
DIMINISH ACROSS THE AREA BY EARLY THIS AFTERNOON. ALONG THE
IMMEDIATE COAST...ONSHORE WINDS HAVE BEEN OBSERVED IN SOME LOCATIONS
AND THERE IS A CHANCE THAT THE WEST TO SOUTHWEST FLOW WILL SPREAD
INLAND ACROSS THE COASTAL PLAIN OF LA AND VENTURA COUNTIES THIS
AFTERNOON INTO THIS EVENING. THE SOUTHWEST FLOW IS FORECAST BY THE
NAM12 MET GUIDANCE TO GUST UP TO AROUND 25 MPH. THE COASTAL WINDS
WILL SHIFT BACK TO OFFSHORE BY AROUND SUNRISE FRIDAY MORNING AND
INCREASE...BUT WITH LOWER SPEEDS THAN WHAT HAS BEEN OBSERVED TODAY.
HOWEVER...IN SPITE OF THE LOWER WINDS SPEEDS...VERY DRY CONDITIONS
AND EXTREME FIRE DANGER WILL CONTINUE THROUGH FRIDAY AFTERNOON.
HUMIDITY RECOVERIES OVERNIGHT WILL BE POOR IN MOST
AREAS...ESPECIALLY WHERE EXPOSED TO OFFSHORE WIND THROUGH THE NIGHT.
HUMIDITIES WILL FALL QUICKLY TO THE SINGLE DIGITS AGAIN FRIDAY
MORNING...WITH MINIMUM READINGS OF 5 PERCENT OR LOWER.
BY EARLY AFTERNOON A MORE WIDESPREAD WIND SHIFT TO THE SOUTHWEST TO
WEST IS EXPECTED. THIS WILL ALLOW HUMIDITIES TO BEGIN TO RISE ACROSS
A LARGER PORTION OF THE COASTAL PLAIN...AND THIS MAY ADVANCE INLAND
TO THE COASTAL VALLEYS OVERNIGHT.
&&
.AVIATION...02/2350Z...GENERALLY HI CONFIDENCE IN THE CURRENT TAFS
WITH VFR CONDITIONS AT ALMOST ALL AIRFIELDS THROUGH FRI. EXCEPTION
IS KSMX WHERE THERE IS A 70 PERCENT CHANCE LOW CLOUDS AND IFR
CONDITIONS SHOULD MOVE INTO THE AIRFIELD BY 05Z THEN CLEAR TO VFR BY
12Z. THERE IS ALSO A 30 PERCENT CHANCE LIFR CONDITIONS COULD AFFECT
KSMX AT TIMES DURING THE PERIOD. GUSTY E WINDS AT KWJF AND KPMD WILL
DIMINISH EARLY THIS EVENING.
KLAX...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU FRI
EVENING.
KBUR...HI CONFIDENCE IN THE CURRENT TAF WITH VFR CONDITIONS THRU FRI.
&&
.LOX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING (SEE LAXRFWLOX).
WIND ADVISORY (SEE LAXNPWLOX).
&&
$$
PUBLIC...30
AVIATION...SIRARD
SYNOPSIS...SETO
FIRE...SMITH
WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS MIAMI FL
959 PM EDT THU MAY 2 2013
.UPDATE...
A CLEARING TREND CONTINUES ACROSS THE REGION WITH HEAVY SHOWERS
AND THUNDERSTORMS EXITING THE LOCAL ATLANTIC WATERS TO THE EAST.
HOWEVER...THERE IS STILL A STILL A CHANCE OF ADDITIONAL SHOWERS AND
ISOLATED THUNDERSTORMS OVERNIGHT. THE OOZ SOUNDING INDICATED STEEP
LOW LEVEL LAPSE RATES AND THERE IS A SURFACE TROUGH DEVELOPING IN
THE EASTERN GULF WITH DEEPER LAYERED TROPICAL MOISTURE STILL
LINGERING ACROSS THE REGION. SOME OF THE MESOSCALE MODEL GUIDANCE
ALSO INDICATED POSSIBLE CONVECTION RETURNING TO THE ATLANTIC
WATERS AND PORTIONS OF EASTERN SOUTH FLORIDA TONIGHT.
60
&&
.PREV DISCUSSION... /ISSUED 747 PM EDT THU MAY 2 2013/
AVIATION...
BULK OF PRECIPITATION HAS MOVED OFFSHORE IN ASSOCIATION WITH
MESOSCALE LOW PRESSURE AREA, OR MESOLOW, WHICH MOVED ACROSS SOUTH
FLORIDA THIS AFTERNOON. LEFTOVER MID/HIGH CLOUDS WILL MOVE THROUGH
THE AREA BY 04Z WITH ONLY SCT CLOUDS AND VFR CONDITIONS OVERNIGHT.
THE MESOLOW IS OFF THE SE FLORIDA COAST AS OF 00Z AND IS LIKELY
CAUSING A TEMPORARY INCREASE IN NE WINDS TO 20-30 KNOTS ALONG THE
EAST COAST. THESE WINDS SHOULD DECREASE LATER THIS EVENING AS THE
LOW MOVES FARTHER OFFSHORE AND THE LARGE SCALE GRADIENT FLOW TAKES
OVER. WINDS SHIFT TO SW ACROSS ALL OF SOUTH FLORIDA ON FRIDAY AS
MAIN SFC LOW MOVES ACROSS THE AREA. SCATTERED TSTMS WILL RETURN TO
THE AREA ON FRIDAY WITH VCTS INCLUDED AT ALL SITES. /MOLLEDA
PREV DISCUSSION... /ISSUED 501 PM EDT THU MAY 2 2013/
UPDATE...
A SMALL CRAFT ADVISORY IS IN EFFECT FROM 2 AM THIS MORNING TO 200
PM FRIDAY FOR THE ATLANTIC WATERS TO THE EAST OF PALM BEACH COUNTY. THE
COMBINATION OF WINDS FORECAST TO INCREASE TO THE 16 TO 21 KNOT
RANGE AND A SMALL LONG PERIOD SWELL WILL RESULT IN SEAS TO NEAR 7
FEET MAINLY EXPECTED TO THE EAST OF PALM BEACH COUNTY.
60
PREV DISCUSSION... /ISSUED 324 PM EDT THU MAY 2 2013/
DISCUSSION...
WIDESPREAD SHOWERS AND THUNDERSTORMS HAVE MOVED ACROSS SOUTH
FLORIDA TODAY. A WELL DEVELOPED MCS/MCV WAS MOVING ACROSS SOUTH
FLORIDA THIS AFTERNOON...AND SOME STORMS HAVE SHOWN ROTATION.
THERE WERE REPORTS OF DAMAGE FROM A STORM IN BOCA RATON EARLIER
THIS AFTERNOON AS WELL. SEVERE STREET FLOODING WAS REPORTED IN THE
BOCA RATON AND DELRAY BEACH AREAS...WHERE OVER 7.5 INCHES OF RAIN
HAS FALLEN.
A SURFACE BOUNDARY APPEARED TO BE DRIFTING SOUTH AND IT WAS
LOCATED ACROSS BROWARD COUNTY THIS AFTERNOON...AND LOCALLY HEAVY
RAIN AND FLOODING WILL BE POSSIBLE ACROSS BROWARD AND MIAMI DADE
COUNTY THROUGH THIS EVENING. AN UPPER LEVEL LOW ACROSS THE
NORTHEASTERN GULF WILL CONTINUE TO SLIDE SOUTHEAST AND OPEN INTO A
TROUGH OVERNIGHT AS IT MOVES INTO THE FLORIDA PENINSULA. UPPER
LEVEL DIVERGENCE FROM THIS UPPER LOW MAY HELP STORMS CONTINUE INTO
THE EVENING BEFORE DIMINISHING. THE HRRR SHOWS SHOWERS
DISSIPATING AFTER 00Z THIS EVENING.
SURFACE LOW PRESSURE IS EXPECTED TO DEVELOP ACROSS THE EASTERN
GULF OF MEXICO AND MOVE OVER SOUTH FLORIDA ON FRIDAY. THIS
WILL ALLOW THE STEERING FLOW OVER SOUTH FLORIDA TO REMAIN LIGHT
FROM A SOUTH TO SOUTHWEST DIRECTION KEEPING THE DEEP TROPICAL
MOISTURE IN PLACE. SO SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE REGION AGAIN ON FRIDAY. THE
EMPHASIS WILL BE FOR THE EAST COAST AND NORTHEAST COAST WHERE THE
BEST LOW LEVEL CONVERGENCE AND THE SURFACE BOUNDARY WILL BE
FOUND...ALONG WITH UPPER LEVEL FORCING ASSOCIATED WITH THE UPPER
LEVEL FLOW.
THE 500 MB TEMPS ON FRIDAY SHOULD BE A LITTLE BIT WARMER THAN
TODAY...DUE TO THE UPPER LEVEL LOW DISSIPATING OVER THE NORTHEAST
GULF OF MEXICO. HOWEVER...ANY STORMS THAT DO AFFECT SOUTH FLORIDA
TONIGHT INTO FRIDAY WILL BE CAPABLE OF PRODUCING HEAVY RAINFALL.
THE LOW WILL CONTINUE TO MOVE EAST OVER SOUTH FLORIDA ON SATURDAY
BEFORE MOVING INTO THE WESTERN ATLANTIC WATERS ON SUNDAY. SLIGHTLY
DRIER CONDITIONS ARE EXPECTED ON SATURDAY...BUT RAIN CHANCES WILL
CONTINUE FOR THE NORTHERN TWO-THIRDS OF THE REGION. MUCH DRIER
AIR WILL WORK INTO THE AREA FROM THE WEST ON SUNDAY.
FOR EARLY TO MIDDLE OF NEXT WEEK...A MID TO UPPER LEVEL LOW WILL
DEVELOP OVER THE TENNESSEE VALLEY AND MOVE SLOWLY EAST TOWARDS THE
MID ATLANTIC STATES. THIS WILL ALLOW FOR DRIER WEATHER TO CONTINUE
TO WORK INTO SOUTH FLORIDA FROM THE WEST. SO THE WEATHER SHOULD
REMAIN DRY OVER SOUTH FLORIDA FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK.
AVIATION...
LIGHT TO MODERATE RAIN WILL CONTINUE AT KAPF AND KPBI THROUGH
ABOUT 21-22Z. VERY HEAVY RAIN AND THUNDERSTORMS WILL CONTINUE FOR
THE REST OF THE EAST COAST TAF SITES...WHERE IFR CONDITIONS MAY
OCCUR. RAIN IS EXPECTED TO BEGIN DIMINISHING AFTER 04-06Z
TONIGHT...WITH IMPROVING CONDITIONS. STORMS WILL BE POSSIBLE AGAIN
BEGINNING LATE MORNING ON FRIDAY. WINDS WILL BE VARIABLE THE REST
OF THIS AFTERNOON WITH GUSTY WINDS POSSIBLE. LIGHT AND VARIABLE
WINDS ARE EXPECTED AFTER MIDNIGHT. WITH LOW PRESSURE MOVING OVER
SOUTH FLORIDA...WESTERLY WINDS ARE EXPECTED ON FRIDAY.
MARINE...
THE WINDS OVER SOUTH FLORIDA TODAY INTO FRIDAY WILL BE FROM THE
SOUTH TO SOUTHEAST DIRECTION AT 10 KNOTS OR LESS...BEFORE SLOWLY
SWINGING TO A NORTHWEST DIRECTION BY LATE THIS WEEKEND AND
INCREASING SPEEDS TO 10 TO 15 KNOTS. AT THE SAME TIME...A SMALL
NORTHEAST SWELL OF 1 TO 3 FEET WILL CONTINUE TO AFFECT THE
ATLANTIC WATERS OF SOUTH FLORIDA LATE THIS WEEK INTO THIS
WEEKEND. THESE CONDITIONS WILL ALLOW FOR THE ATLANTIC SEAS TO
REMAIN BELOW 6 FEET TODAY INTO THIS WEEKEND...EXCEPT FOR THE PALM
BEACH WATERS WHERE THE SEAS COULD BUILD TO 6 FEET THIS WEEKEND.
FOR THE GULF SIDE...THE SEAS WILL REMAIN BELOW 6 FEET TODAY INTO
THIS WEEKEND. THE ONLY EXCEPTION IS THE OFFSHORE GULF WATERS WHERE
THE SEAS COULD BUILD TO 6 FEET BY THIS WEEKEND.
FIRE WEATHER...
DEEP TROPICAL MOISTURE WILL REMAIN OVER THE REGION ON FRIDAY WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. SLIGHTLY DRIER
AIR WILL BEGIN TO MOVE INTO THE REGION ON SATURDAY...WITH LESSER
RAIN CHANCES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 83 69 87 / 50 70 40 30
FORT LAUDERDALE 72 83 73 88 / 50 60 30 20
MIAMI 72 84 72 87 / 40 60 30 10
NAPLES 67 83 68 87 / 30 50 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 AM TO 2 PM EDT
FRIDAY FOR COASTAL WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL OUT 20 NM-WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...60/BD
AVIATION/RADAR...59/RM
AREA FORECAST DISCUSSION
NWS MIAMI FL
747 PM EDT THU MAY 2 2013
.AVIATION...
BULK OF PRECIPITATION HAS MOVED OFFSHORE IN ASSOCIATION WITH
MESOSCALE LOW PRESSURE AREA, OR MESOLOW, WHICH MOVED ACROSS SOUTH
FLORIDA THIS AFTERNOON. LEFTOVER MID/HIGH CLOUDS WILL MOVE THROUGH
THE AREA BY 04Z WITH ONLY SCT CLOUDS AND VFR CONDITIONS OVERNIGHT.
THE MESOLOW IS OFF THE SE FLORIDA COAST AS OF 00Z AND IS LIKELY
CAUSING A TEMPORARY INCREASE IN NE WINDS TO 20-30 KNOTS ALONG THE
EAST COAST. THESE WINDS SHOULD DECREASE LATER THIS EVENING AS THE
LOW MOVES FARTHER OFFSHORE AND THE LARGE SCALE GRADIENT FLOW TAKES
OVER. WINDS SHIFT TO SW ACROSS ALL OF SOUTH FLORIDA ON FRIDAY AS
MAIN SFC LOW MOVES ACROSS THE AREA. SCATTERED TSTMS WILL RETURN TO
THE AREA ON FRIDAY WITH VCTS INCLUDED AT ALL SITES. /MOLLEDA
&&
.PREV DISCUSSION... /ISSUED 501 PM EDT THU MAY 2 2013/
UPDATE...
A SMALL CRAFT ADVISORY IS IN EFFECT FROM 2 AM THIS MORNING TO 200
PM FRIDAY FOR THE ATLANTIC WATERS TO THE EAST OF PALM BEACH COUNTY. THE
COMBINATION OF WINDS FORECAST TO INCREASE TO THE 16 TO 21 KNOT
RANGE AND A SMALL LONG PERIOD SWELL WILL RESULT IN SEAS TO NEAR 7
FEET MAINLY EXPECTED TO THE EAST OF PALM BEACH COUNTY.
60
PREV DISCUSSION... /ISSUED 324 PM EDT THU MAY 2 2013/
DISCUSSION...
WIDESPREAD SHOWERS AND THUNDERSTORMS HAVE MOVED ACROSS SOUTH
FLORIDA TODAY. A WELL DEVELOPED MCS/MCV WAS MOVING ACROSS SOUTH
FLORIDA THIS AFTERNOON...AND SOME STORMS HAVE SHOWN ROTATION.
THERE WERE REPORTS OF DAMAGE FROM A STORM IN BOCA RATON EARLIER
THIS AFTERNOON AS WELL. SEVERE STREET FLOODING WAS REPORTED IN THE
BOCA RATON AND DELRAY BEACH AREAS...WHERE OVER 7.5 INCHES OF RAIN
HAS FALLEN.
A SURFACE BOUNDARY APPEARED TO BE DRIFTING SOUTH AND IT WAS
LOCATED ACROSS BROWARD COUNTY THIS AFTERNOON...AND LOCALLY HEAVY
RAIN AND FLOODING WILL BE POSSIBLE ACROSS BROWARD AND MIAMI DADE
COUNTY THROUGH THIS EVENING. AN UPPER LEVEL LOW ACROSS THE
NORTHEASTERN GULF WILL CONTINUE TO SLIDE SOUTHEAST AND OPEN INTO A
TROUGH OVERNIGHT AS IT MOVES INTO THE FLORIDA PENINSULA. UPPER
LEVEL DIVERGENCE FROM THIS UPPER LOW MAY HELP STORMS CONTINUE INTO
THE EVENING BEFORE DIMINISHING. THE HRRR SHOWS SHOWERS
DISSIPATING AFTER 00Z THIS EVENING.
SURFACE LOW PRESSURE IS EXPECTED TO DEVELOP ACROSS THE EASTERN
GULF OF MEXICO AND MOVE OVER SOUTH FLORIDA ON FRIDAY. THIS
WILL ALLOW THE STEERING FLOW OVER SOUTH FLORIDA TO REMAIN LIGHT
FROM A SOUTH TO SOUTHWEST DIRECTION KEEPING THE DEEP TROPICAL
MOISTURE IN PLACE. SO SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE REGION AGAIN ON FRIDAY. THE
EMPHASIS WILL BE FOR THE EAST COAST AND NORTHEAST COAST WHERE THE
BEST LOW LEVEL CONVERGENCE AND THE SURFACE BOUNDARY WILL BE
FOUND...ALONG WITH UPPER LEVEL FORCING ASSOCIATED WITH THE UPPER
LEVEL FLOW.
THE 500 MB TEMPS ON FRIDAY SHOULD BE A LITTLE BIT WARMER THAN
TODAY...DUE TO THE UPPER LEVEL LOW DISSIPATING OVER THE NORTHEAST
GULF OF MEXICO. HOWEVER...ANY STORMS THAT DO AFFECT SOUTH FLORIDA
TONIGHT INTO FRIDAY WILL BE CAPABLE OF PRODUCING HEAVY RAINFALL.
THE LOW WILL CONTINUE TO MOVE EAST OVER SOUTH FLORIDA ON SATURDAY
BEFORE MOVING INTO THE WESTERN ATLANTIC WATERS ON SUNDAY. SLIGHTLY
DRIER CONDITIONS ARE EXPECTED ON SATURDAY...BUT RAIN CHANCES WILL
CONTINUE FOR THE NORTHERN TWO-THIRDS OF THE REGION. MUCH DRIER
AIR WILL WORK INTO THE AREA FROM THE WEST ON SUNDAY.
FOR EARLY TO MIDDLE OF NEXT WEEK...A MID TO UPPER LEVEL LOW WILL
DEVELOP OVER THE TENNESSEE VALLEY AND MOVE SLOWLY EAST TOWARDS THE
MID ATLANTIC STATES. THIS WILL ALLOW FOR DRIER WEATHER TO CONTINUE
TO WORK INTO SOUTH FLORIDA FROM THE WEST. SO THE WEATHER SHOULD
REMAIN DRY OVER SOUTH FLORIDA FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK.
AVIATION...
LIGHT TO MODERATE RAIN WILL CONTINUE AT KAPF AND KPBI THROUGH
ABOUT 21-22Z. VERY HEAVY RAIN AND THUNDERSTORMS WILL CONTINUE FOR
THE REST OF THE EAST COAST TAF SITES...WHERE IFR CONDITIONS MAY
OCCUR. RAIN IS EXPECTED TO BEGIN DIMINISHING AFTER 04-06Z
TONIGHT...WITH IMPROVING CONDITIONS. STORMS WILL BE POSSIBLE AGAIN
BEGINNING LATE MORNING ON FRIDAY. WINDS WILL BE VARIABLE THE REST
OF THIS AFTERNOON WITH GUSTY WINDS POSSIBLE. LIGHT AND VARIABLE
WINDS ARE EXPECTED AFTER MIDNIGHT. WITH LOW PRESSURE MOVING OVER
SOUTH FLORIDA...WESTERLY WINDS ARE EXPECTED ON FRIDAY.
MARINE...
THE WINDS OVER SOUTH FLORIDA TODAY INTO FRIDAY WILL BE FROM THE
SOUTH TO SOUTHEAST DIRECTION AT 10 KNOTS OR LESS...BEFORE SLOWLY
SWINGING TO A NORTHWEST DIRECTION BY LATE THIS WEEKEND AND
INCREASING SPEEDS TO 10 TO 15 KNOTS. AT THE SAME TIME...A SMALL
NORTHEAST SWELL OF 1 TO 3 FEET WILL CONTINUE TO AFFECT THE
ATLANTIC WATERS OF SOUTH FLORIDA LATE THIS WEEK INTO THIS
WEEKEND. THESE CONDITIONS WILL ALLOW FOR THE ATLANTIC SEAS TO
REMAIN BELOW 6 FEET TODAY INTO THIS WEEKEND...EXCEPT FOR THE PALM
BEACH WATERS WHERE THE SEAS COULD BUILD TO 6 FEET THIS WEEKEND.
FOR THE GULF SIDE...THE SEAS WILL REMAIN BELOW 6 FEET TODAY INTO
THIS WEEKEND. THE ONLY EXCEPTION IS THE OFFSHORE GULF WATERS WHERE
THE SEAS COULD BUILD TO 6 FEET BY THIS WEEKEND.
FIRE WEATHER...
DEEP TROPICAL MOISTURE WILL REMAIN OVER THE REGION ON FRIDAY WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. SLIGHTLY DRIER
AIR WILL BEGIN TO MOVE INTO THE REGION ON SATURDAY...WITH LESSER
RAIN CHANCES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 83 69 87 / 80 70 40 30
FORT LAUDERDALE 72 83 73 88 / 80 60 30 20
MIAMI 72 84 72 87 / 80 60 30 10
NAPLES 67 83 68 87 / 40 50 20 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 2 AM TO 2 PM EDT
FRIDAY FOR COASTAL WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL OUT 20 NM-WATERS FROM JUPITER INLET TO DEERFIELD
BEACH, FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
PUBLIC/MARINE...60/BD
AVIATION/RADAR/FIRE...59/MOLLEDA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
348 PM EDT WED MAY 1 2013
.DISCUSSION...
...HEAVY RAIN MOVING NORTH ACROSS LAKE OKEECHOBEE AND THE TREASURE
COAST REGION THIS AFTERNOON...
CURRENT...LARGE SQUALL LINE EXTENDING FROM TAMPA BAY TO THE SW
SHORE OF LAKE OKEECHOBEE WILL LIFT N INTO E CENTRAL FL THRU THE
REMAINDER OF THE AFTN. SCT SHRAS/ISOLD TSRAS DVLPG BCMG NMRS THRU
LATE AFTN. HEAVY RAIN AND FQNT CG LTG PRIMARY THREATS. NO
INDICATIONS OF SVR WND/HAIL FROM WFO TAMPA OR WFO MIAMI...THOUGH
STORMS OVER LAKE OKEECHOBEE HAVE PROMPTED SPECIAL MARINE WARNINGS.
SCT SHRAS/ISOLD TSRAS HAVE DVLPD ALONG AND N OF THE FL
TURNPIKE...EXPECT THIS ACTIVITY WILL ROB THE SQUALL LINE OF MUCH
OF THE NECESSARY ENERGY TO GENERATE SVR WX...THOUGH 40-50MPH SFC
GUSTS WILL BE POSSIBLE THRU EARLY EVENING. TEMPS ALOFT HAVE WARMED
A TOUCH...BUT RUC ANALYSIS STILL SHOWS MUCH OF CENTRAL FL BTWN
-10C AND -11C.
SCT/NMRS SHRAS AND ISOLD TSRAS WILL LINGER INTO LATE EVNG WITH
ACTIVITY DIMINISHING AS SFC BNDRY INTERACTIONS PLAY OUT. MOIST
ONSHORE FLOW WILL ALLOW FOR A SCT COASTAL SHOWERS THROUGH THE
OVERNIGHT HOURS...ESPECIALLY AS ADDITIONAL RIPPLES OF H85-H50
VORTICITY OVER THE ERN AND CENTRAL GOMEX WORK THEIR WAY ACRS THE FL
PENINSULA. MILD NIGHT WITH LOWS IN THE M/U60S...L70S PSBL ALONG THE
IMMEDIATE TREASURE COAST.
THURSDAY...
ANOTHER ROUND OF RAIN IN THE WORKS FOR E CNTRL FL. SHORT WAVE TROF
AXIS CENTERED OVER THE LWR MS VALLEY WILL REMAIN NEARLY STATIONARY
WITH ITS ASSOCD SFC LOW SAGGING INTO THE ERN GULF. INTERACTION BTWN
THE TROF AND A STRONG SFC RIDGE PARKED ALONG THE ERN SEABOARD WILL
ALLOW WINDS TO FRESHEN OUT OF THE E/NE. DEEP MOISTURE POOLING WITHIN
THE TROF WILL REMAIN OVER CENTRAL FL...KEEPING PWATS BTWN 1.5"-1.6".
SRN BRANCH OF THE JET STREAM WILL REMAIN S OF CENTRAL FL WHERE IT
WILL CONTINUE TO PRODUCE STRONG UPR LVL DIVERGENCE. TEMPS ALOFT WILL
TAKE ANOTHER DIP AS H50 TEMPS BTWN -12C AND -14C OVER THE NW GOMEX
WORK THEMSELVES INTO THE REGION.
MOS GUIDANCE CONTINUES TO INDICATE POPS NEAR OR ABV 70PCT...GIVING
IT GOOD RUN-TO-RUN CONSISTENCY. CAN SEE NO AREA THAT IS OVERLY
FAVORED...WILL PAINT THE ENTIRE CWA WITH 70PCT. THE INCREASED LOW
LEVEL FLOW WILL ENHANCE THE POTENTIAL FOR HEAVY RAIN.
FRI-SUN...(PREVIOUS) THE NAM AND GFS SHOW THE WEAK SURFACE LOW
PUSHING EAST TOWARDS THE SOUTHERN PART OF THE STATE. THIS WOULD
KEEP THE AREA IN A MOIST ONSHORE WIND FLOW. THERE IS SOME
UNCERTAINTY THOUGH IN THE EVOLUTION OF THIS SYSTEM AS THE 00Z
ECMWF SHOWS A BROAD LOW OVER THE STATE BY THE WEEKEND. WILL FOLLOW
CLOSER TO THE GFS THOUGH AS THE SURFACE HIGH PRESSURE RIDGE OVER
THE EASTERN SEABOARD SHOULD SUSTAIN AN ONSHORE WIND. THIS IS IN
AGREEMENT WITH THE LATEST WPC PROGS.
WITH BREEZY EASTERLY FLOW...THERE SHOULD BE A CONTINUED CHANCE FOR
HEAVY RAIN...ESPECIALLY FRI AND MAYBE INTO SAT. WILL FOLLOW CLOSE
TO MOS POPS AND HAVE INDICATED 50-60 PERCENT RAIN CHANCES FOR FRI-
SAT.
TAKEN AT FACE VALUE...THE GFS SOLUTION ALSO SHOWS LOW LEVEL
VEERING FLOW DUE TO THE APPROACHING SURFACE LOW. THIS COULD BRING
A SLIGHT RISK OF TORNADOES. BY SUN BOTH THE GFS AND ECMWF SHOW
DRYING AND HAVE FOLLOWED THE PREVIOUS FORECAST TREND FOR LOWERING
POPS.
MON-WED...THE MEDIUM RANGE MODELS DIVERGE WITH THE GFS SHOWING A
LOW PRESSURE CENTER VICINITY OF THE MID ATLANTIC COAST...WHICH
PUSHES A WEAK FRONT THROUGH THE LOCAL AREA. THE ECMWF INDICATES A
BROAD LOW FARTHER SOUTH AND WEAKER...WITH BASICALLY AN ONSHORE
WIND FLOW DUE TO THE LARGE SURFACE HIGH PRESSURE RIDGE ALONG THE
EASTERN SEABOARD. THIS SOLUTION IS CLOSER TO THE WPC PROGS SO HAVE
FOLLOWED CLOSE TO THAT SCENARIO FOR NOW. WILL CARRY SLIGHT CHANCE
POPS MON THEN MAINTAIN THE DRYING TREND FROM THE PREVIOUS
FORECAST. OF COURSE...THIS PART OF THE FORECAST COULD BE SUBJECT
TO SIGNIFICANT CHANGES.
&&
.AVIATION...
THRU 02/00Z...SQLN LN EXTENDING FROM LAKE OKEECHOBEE TO TAMPA BAY
WILL LIFT N/NE...NMRS MVFR SHRAS/SCT IFR TSRAS DVLPG ALL SITES BCMG
WDSPRD W OF I-95...ISOLD LIFR CIGS/VSBYS IN +TSRA WITH SFC WND
G35KTS PSBL. BTWN 02/02Z-02/04Z...TSRAS ENDING...CHC OF MVFR SHRAS
ALL SITES CONTG THRU 02/14Z...AREAS MVFR CIGS N OF KMLB-KISM.
&&
.MARINE...
TONIGHT-THURSDAY...WINDS WILL FRESHEN OUT OF THE E/NE AS A HIGH PRES
RIDGE OVER THE ERN SEABOARD INTERACTS WITH A DLVPG STORM SYSTEM OVER
THE GOMEX. FRESH SWELL WILL WORK ITS WAY INTO THE LCL ATLC AS THE
WINDS INCREASE...SEAS 4-5FT OVERNIGHT WILL BUILD TO 5-6FT NEARSHORE
AND 6-8FT OFFSHORE...DOMINANT PDS SHORTENING TO 9-10SEC.
FRI...(PREVIOUS) SURFACE HIGH PRESSURE RIDGE ALONG THE EASTERN
SEABOARD AND WEAK LOW PRESSURE IN THE EASTERN GULF SHOULD LEAD TO
CONTINUED FRESH EASTERLY WINDS WITH MOST OF THE WATERS WILL BE
AROUND 20+ KNOTS. IN ADDITION...INCREASING LOW LEVEL CONVERGENCE
SHOULD PRODUCE BANDS OF SHOWERS/STORMS WITH A FAIRLY HIGH COVERAGE
EXPECTED.
WEEKEND...THE FORECAST DEPENDS ON THE EVOLUTION OF THE SURFACE LOW
THAT IS FORECAST TO BE PUSHING ACROSS THE SOUTHERN PART OF THE
STATE. RIGHT NOW IT LOOKS LIKE ADVISORY CONDITIONS MIGHT BE
CONTINUING ON SAT WITH GRADUALLY DECREASING EAST WINDS ON SUNDAY.
CONFIDENCE IS NOT HIGH THOUGH...SO MARINERS WILL NEED TO MONITOR
THE LATEST FORECAST TRENDS FOR THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 66 77 66 80 / 50 70 50 50
MCO 66 83 65 84 / 50 70 50 60
MLB 68 80 69 80 / 50 70 50 60
VRB 68 80 68 81 / 50 70 40 60
LEE 65 83 65 83 / 50 70 40 60
SFB 65 83 65 83 / 50 70 50 50
ORL 66 83 67 83 / 50 70 50 60
FPR 68 79 67 82 / 60 70 40 60
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...BRAGAW
LONG TERM....PENDERGRAST
RADAR...VOLKMER
AREA FORECAST DISCUSSION
NWS MIAMI FL
238 PM EDT WED MAY 1 2013
.SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)...
LARGE CUT-OFF MID LEVEL LOW CONTINUES TO SLOWLY DRIFT EAST ACROSS
THE SOUTH CENTRAL GULF STATES. A LARGE CLUSTER OF CONVECTION
DEVELOPED ON THE SOUTHERN FRINGES OF THIS LOW AND HAS MOVED EAST
THROUGH EARLY THIS AFTERNOON AND AS OF 1830Z WAS MOVING ACROSS THE
INTERIOR AND TOWARDS THE EAST COAST METRO AREA. ANOTHER CLUSTER OF
CONVECTION IS ALSO CURRENTLY DEVELOPING OVER THE CENTRAL GULF WITH
THE HRRR SHOWING THIS MOVING ACROSS SOUTH FLORIDA THIS EVENING SO
HAVE INCREASED THE POPS FOR THE OVERNIGHT HOURS. AT THE SAME TIME, A
DEEPENING TROUGH INTO THE CENTRAL PLAINS STATES ON THURSDAY WILL
CONTINUE TO DEEPEN AND CUT OFF OVER THE MISSISSIPPI VALLEY WITH
THE SOUTHERN CUT-OFF LOW BECOMING PHASED IN WITH THIS LOW. THIS
KEEPS SOUTH FLORIDA IN RICH TROPICAL FLOW OF AIR THROUGH THE END
OF THE WEEK WITH HIGH CHANCES FOR SHOWERS AND THUNDERSTORMS.
FORECAST SOUNDINGS THROUGH THIS PERIOD LOOK QUITE SIMILAR WITH
PWAT REMAINING WELL ABOVE NORMAL FOR EARLY MAY AND A WEAK WESTERLY
STEERING FLOW. GLOBAL MODELS ARE NOW MORE IN AGREEMENT WITH THE
OVERALL SOLUTION DURING THE NEXT 48 HOURS AND SHOW THE LOW
DRIFTING TO THE SOUTHEAST BEFORE GETTING PHASED IN WITH THE
UPSTREAM DEEPENING TROUGH. THIS ON THURSDAY AND POSSIBLY FRIDAY
WILL DESTABILIZE THE ATMOSPHERE WITH COOLING 500 MB TEMPERATURES.
THE 12Z MFL SOUNDING SHOWED A TEMPERATURE OF -10 CELSIUS AND THE
GFS SHOWS COOLING TO AROUND -12 ON THURSDAY INTO FRIDAY. SO THE
CONTINUED THREAT FOR STRONG STORMS WILL ALSO BE A FACTOR. OF
COURSE THERE WILL ALWAYS BE SOME DAY TO DAY FLUCTUATIONS WITH WEAK
DISTURBANCES MOVING THROUGH THE BASE OF THE TROUGH.
.LONG TERM (SATURDAY THROUGH WEDNESDAY)...
THE EXTENDED PORTION OF THE FORECAST CONTINUES TO BE HIGHLY
UNCERTAIN WITH THE GFS AND ECMWF HAVING TWO DIFFERENT SOLUTIONS TO
THE DEEPENING TROUGH. BOTH CUT THIS LOW OFF FROM THE NORTHERN
LATITUDE FLOW AS MENTIONED ABOVE. THE GFS THEN DEVELOPS A MASSIVE
CUT-OFF LOW AND THEN SLOWLY DRIFTS IT TO THE EAST THROUGH THE MIDDLE
OF NEXT WEEK. THIS WOULD TEND TO DRAW A DRIER AIR MASS ACROSS SOUTH
FLORIDA FOR LESSER STORM ACTIVITY. HOWEVER, THE ECMWF SPLITS THE
CUT-OFF LOW DRIFTING THE SOUTHERN PORTION TO THE SOUTH WHICH WOULD
KEEP SOUTH FLORIDA VERY UNSTABLE. FOR NOW, WILL GO WITH THE GFS
SOLUTION AS THIS MODEL HAS BEEN THE MOST CONSISTENT IN ITS FORECAST
WHERE THE ECMWF HAS HAD DIFFERENT SOLUTIONS WITH EACH RUN.
&&
.MARINE...
TRANQUIL CONDITIONS OUTSIDE OF ISOLATED STRONG CONVECTION WILL
CONTINUE THROUGH THURSDAY. SOME INCREASE IN A NORTHEAST SWELL IS
EXPECTED LATE IN THE WEEK INTO THE WEEKEND WITH POSSIBLE SEAS
BUILDING TO 7 FEET OVER THE PALM BEACH WATERS.
&&
.FIRE WEATHER...
NO PROBLEMS OR CONCERNS WITH DEEP TROPICAL MOISTURE REMAINING IN PLACE.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 72 81 70 81 / 60 70 50 60
FORT LAUDERDALE 71 81 71 82 / 60 70 50 60
MIAMI 75 81 71 83 / 60 70 50 60
NAPLES 68 85 67 83 / 60 50 40 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...23/SK
AREA FORECAST DISCUSSION
NWS MIAMI FL
204 PM EDT WED MAY 1 2013
.AVIATION...
SIGNIFICANT TAF CHANGES WITH 18Z UPDATE DUE TO EVOLVING MCS THAT
IS MOVING THROUGH KAPF. PRESENT MOTION PLACES THE LEADING EDGE OF
COMPLEX INTO EAST COAST TERMINALS BY 20Z...SO HAVE ADDED
PREVAILING TSRA FROM 1930-22Z...ALONG WITH MVFR CONDITIONS. LIKELY
IFR RESTRICTIONS FOR RELATIVELY BRIEF TIMES. SIGNIFICANT WINDS ARE
POSSIBLE WITH THE CONVECTIVE BAND...AND GUSTS IN EXCESS OF 35 KTS
ARE REALISTIC. SHOWERS AND THUNDERSTORMS COULD CONTINUE
OVERNIGHT...AND WILL LIKELY REINVIGORATE DURING THE MORNING
THURSDAY. VCSH WARRANTED BUT CONFIDENCE TOO LOW FOR PREVAIL PCPN ATTM.
&&
.PREV DISCUSSION... /ISSUED 943 AM EDT WED MAY 1 2013/
UPDATE...
MASSIVE CLOUD FIELD CURRENTLY OVER THE EASTERN GOFMEX ASSOCIATED
WITH LARGE CONVECTIVE COMPLEX ROTATING BENEATH CUT-OFF LOW WHICH
IS OVER THE SOUTH CENTRAL GULF STATES. THIS LINE OF CONVECTION
HAS BEEN PRODUCING A TREMENDOUS AMOUNT OF LIGHTNING WITH NEARLY 800
STRIKES IN THE PAST 15 MINUTES. THE CONVECTIVE FIELD IS MOVING
EAST BUT THE QUESTION IS IF IT WILL HOLD TOGETHER BEFORE REACHING
THE LOCAL GULF WATERS AND HOW MUCH EFFECT THE DEBRIS CLOUD FIELD
WILL HAVE ON DIURNAL HEATING OVER THE MAINLAND. FORECAST SOUNDINGS
ALONG WITH THE 12Z MFL SOUNDING WOULD SUGGEST THE POSSIBILITY OF
AT LEAST SOME STRONG STORMS ESPECIALLY ALONG THE EAST COAST WITH
THE LOW LEVEL SOUTHEAST FLOW. HOWEVER, IT IS ALSO POSSIBLE THAT
HEATING WILL BE HELD OFF ENOUGH TO NOT ALLOW SIGNIFICANT UPDRAFTS
TO OCCUR. THE HRRR IS SHOWING SOME WEAKENING AS THE SYSTEM
APPROACHES THE GULF COAST BUT WITH ADDITIONAL DEVELOPMENT OVER THE
MAINLAND AS SOME HEATING TAKES PLACE WITH MOVEMENT TOWARDS THE
EAST COAST. THE 12Z MFL SOUNDING DOES INDICATE A STORM MOTION TO
THE EAST AT AROUND 5 KNOTS. ALL OF THIS SAID, CURRENT THINKING IS
TO ADD MENTION OF POSSIBLE STRONG STORMS FOR THIS AFTERNOON AND
EXTEND HIGHER POPS BACK TO THE WEST COAST TO ACCOUNT FOR THE
APPROACHING CONVECTION.
KOB
PREV DISCUSSION... /ISSUED 807 AM EDT WED MAY 1 2013/
AVIATION...
TODAY WILL LIKELY BE A REPLAY OF THE LAST COUPLE OF DAYS, ONCE AGAIN.
EXPECT SOME CONVECTIVE SHOWER ACTIVITY IN THE MORNING, THEN THUNDERSTORMS
TO DEVELOP IN THE LATE MORNING TO EARLY AFTERNOON. THESE CAN LEAD TO
MVFR AND IFR CONDITIONS AT TIMES. HAVE ADDED PROB30 GROUPS TO ALL EAST
COAST TAF SITES FOR THE AFTERNOON HOURS. THIS TIME THERE IS A BETTER
CHANCE TSTMS COULD LINGER INTO THE EVENING HOURS SO LEFT VCTS IN THE
FORECAST FOR THE EVENING HOURS ALSO. WINDS WILL BE LIGHT AND VARIABLE
THIS MORNING AND PICK UP OUT OF THE SOUTHEAST MID TO LATE MORNING AROUND
10 KTS WITH A CHANCE OF A SOUTHWEST SEA BREEZE OF 5 T0 10 KNOTS AT APF
IN THE MID TO LATE AFTERNOON FOR A COUPLE OF HOURS.
PREV DISCUSSION... /ISSUED 416 AM EDT WED MAY 1 2013/
WET WEATHER CONTINUES OVER SOUTH FLORIDA THROUGH EARLY THIS WEEKEND...
SOME STRONG STORMS POSSIBLE TODAY AND AGAIN THURSDAY OVER SOUTH FLORIDA...
SHORT TERM...
LOW PRESSURE OVER THE WESTERN ATLANTIC WATERS WILL MOVE EAST TODAY
AS A MID TO UPPER LEVEL LOW OVER THE SOUTHERN GULF COAST STATES
MOVES SOUTHEAST INTO THE NORTHERN GULF OF MEXICO. THIS WILL ALLOW
FOR A TROUGH OF LOW PRESSURE OVER CENTRAL FLORIDA TO MOVE SOUTH INTO
THE LAKE OKEECHOBEE REGION TODAY KEEPING THE STEERING FLOW IN A
SOUTH TO SOUTHWEST DIRECTION OVER SOUTH FLORIDA. SO THE DEEP
TROPICAL MOISTURE WILL CONTINUE TO WORK INTO THE AREA FROM THE SOUTH
ALLOWING FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. THE
STORMS WILL ALSO BE SLOW MOVERS TODAY LEADING TO HEAVY RAINFALL OVER
SOUTH FLORIDA. SO WILL CONTINUE TO MENTION THE HEAVY RAINFALL IN THE
ZONES FOR TODAY OVER SOUTH FLORIDA.
THE TROUGH OF LOW PRESSURE WILL REMAIN NEARLY STATIONARY TONIGHT
INTO THURSDAY...AS THE MID TO UPPER LEVEL LOW MOVES SLOWLY
SOUTHEAST INTO THE EASTERN GULF OF MEXICO. A SURFACE LOW WILL
ALSO DEVELOP IN THE EASTERN GULF OF MEXICO ON THURSDAY WHICH WILL
HELP KEEP THE SOUTH TO SOUTHWEST STEERING FLOW OVER SOUTH FLORIDA
ALONG WITH THE DEEP TROPICAL MOISTURE. SO WILL CONTINUE THE
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER SOUTH FLORIDA
FOR THURSDAY ALONG WITH THE HEAVY RAINFALL WORDING.
THE 500 MB TEMPS WILL ALSO COOL OFF A BIT FROM AROUND -10C THIS
MORNING TO -12C TO -13C ON THURSDAY. THIS WILL ALLOW FOR SOME STRONG
STORMS OVER SOUTH FLORIDA TODAY...AND STRONG TO EVEN SEVERE STORMS
(WITH POTENTIAL FOR MORE THAN THE ORDINARY DEPENDING HOW MUCH
SURFACE HEATING WE END UP GETTING) ON THURSDAY OVER SOUTH FLORIDA.
ALTHOUGH THE PRIMARY THREAT FROM THE STORMS WILL CONTINUE TO BE
FLOODING POTENTIAL...SECONDARY THREATS FROM THE STORMS WILL BE GUSTY
WINDS...HAIL...AND FREQUENT LIGHTING STRIKES.
THE LOW OVER THE EASTERN GULF OF MEXICO WILL SLOWLY MOVE EAST ON
FRIDAY TOWARDS SOUTH FLORIDA...AS THE TROUGH OF LOW PRESSURE
REMAINS OVER SOUTH FLORIDA. THIS WILL CONTINUE TO KEEP THE DEEP
TROPICAL MOISTURE IN PLACE OVER SOUTH FLORIDA ON FRIDAY. SO WILL
CONTINUE THE SCATTERED TO NUMEROUS POPS OVER THE AREA FOR FRIDAY
ALONG WITH THE HEAVY RAINFALL WORDING.
LONG TERM...
THE LOW WILL MOVE EAST OVER SOUTH FLORIDA ON SATURDAY BEFORE
MOVING INTO THE WESTERN ATLANTIC WATERS ON SUNDAY. THIS WILL KEEP
THE AREA IN THE DEEP TROPICAL MOISTURE ON SATURDAY...BEFORE
ALLOWING FOR SOME DRIER AIR TO WORK INTO THE AREA FROM THE WEST ON
SUNDAY. THEREFORE...THE POPS ON SATURDAY WILL BE IN THE SCATTERED
RANGE OVER SOUTH FLORIDA WHILE ON SUNDAY THE POPS WILL BE IN SLIGHT
CHANCE TO LOW END CHANCE.
FOR EARLY NEXT WEEK...THE DRIER WEATHER WILL CONTINUE TO WORK INTO
THE AREA FROM THE NORTH AND WEST. SO THE WEATHER SHOULD BE DRY
OVER SOUTH FLORIDA FOR EARLY NEXT WEEK...AND WILL REMOVE THE SHOWER
AND THUNDERSTORM WORDING OVER SOUTH FLORIDA FOR EARLY NEXT WEEK.
HOWEVER...THERE REMAINS QUITE A BIT OF UNCERTAINTY AMONG THE MODELS
AND THIS OUTLOOK COULD CHANGE WITH THE WET PERIOD EITHER ENDING
EARLIER THAN SUNDAY OR LATER THAN ANTICIPATED INTO EARLY NEXT WEEK.
MARINE...
THE WINDS OVER SOUTH FLORIDA TODAY INTO THURSDAY WILL BE FROM THE
EAST TO SOUTHEAST AT 10 KNOTS OR LESS...BEFORE INCREASING TO
BREEZY CONDITIONS BY EARLY THIS WEEKEND FROM THE SOUTHERLY
DIRECTION. AT THE SAME TIME...A NORTHEAST SWELL OF 2 TO 3 FEET
WILL ALSO CONTINUE TO AFFECT THE PALM BEACH WATERS OF SOUTH
FLORIDA. THIS WILL ALLOW FOR THE SEAS TO REMAIN BELOW 6 FEET IN
THE ATLANTIC WATERS TODAY INTO THURSDAY...BEFORE INCREASING TO 7
FEET BY FRIDAY IN THE PALM BEACH WATERS. FOR THE GULF SIDE...THE
SEAS WILL REMAIN BELOW 6 FEET TODAY INTO EARLY THIS WEEKEND.
FIRE WEATHER...
THE RELATIVE HUMIDITIES WILL REMAIN ABOVE THE 35 PERCENT CRITICAL
VALUE EACH DAY OVER SOUTH FLORIDA THROUGH END OF THIS WEEK...DUE
TO THE TROPICAL MOISTURE REMAINING OVER THE AREA. SO NO PROBLEMS
ARE EXPECTED WITH THE FIRE WEATHER OVER SOUTH FLORIDA.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 70 82 70 82 / 50 70 50 60
FORT LAUDERDALE 71 82 71 83 / 50 70 50 60
MIAMI 71 83 71 84 / 50 70 50 60
NAPLES 68 85 68 85 / 50 50 40 50
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...30/KOB
AVIATION/RADAR...23/SK
AREA FORECAST DISCUSSION
NWS MIAMI FL
943 AM EDT WED MAY 1 2013
.UPDATE...
MASSIVE CLOUD FIELD CURRENTLY OVER THE EASTERN GOFMEX ASSOCIATED
WITH LARGE CONVECTIVE COMPLEX ROTATING BENEATH CUT-OFF LOW WHICH
IS OVER THE SOUTH CENTRAL GULF STATES. THIS LINE OF CONVECTION
HAS BEEN PRODUCING A TREMENDOUS AMOUNT OF LIGHTNING WITH NEARLY 800
STRIKES IN THE PAST 15 MINUTES. THE CONVECTIVE FIELD IS MOVING
EAST BUT THE QUESTION IS IF IT WILL HOLD TOGETHER BEFORE REACHING
THE LOCAL GULF WATERS AND HOW MUCH EFFECT THE DEBRIS CLOUD FIELD
WILL HAVE ON DIURNAL HEATING OVER THE MAINLAND. FORECAST SOUNDINGS
ALONG WITH THE 12Z MFL SOUNDING WOULD SUGGEST THE POSSIBILITY OF
AT LEAST SOME STRONG STORMS ESPECIALLY ALONG THE EAST COAST WITH
THE LOW LEVEL SOUTHEAST FLOW. HOWEVER, IT IS ALSO POSSIBLE THAT
HEATING WILL BE HELD OFF ENOUGH TO NOT ALLOW SIGNIFICANT UPDRAFTS
TO OCCUR. THE HRRR IS SHOWING SOME WEAKENING AS THE SYSTEM
APPROACHES THE GULF COAST BUT WITH ADDITIONAL DEVELOPMENT OVER THE
MAINLAND AS SOME HEATING TAKES PLACE WITH MOVEMENT TOWARDS THE
EAST COAST. THE 12Z MFL SOUNDING DOES INDICATE A STORM MOTION TO
THE EAST AT AROUND 5 KNOTS. ALL OF THIS SAID, CURRENT THINKING IS
TO ADD MENTION OF POSSIBLE STRONG STORMS FOR THIS AFTERNOON AND
EXTEND HIGHER POPS BACK TO THE WEST COAST TO ACCOUNT FOR THE
APPROACHING CONVECTION.
KOB
&&
.PREV DISCUSSION... /ISSUED 807 AM EDT WED MAY 1 2013/
AVIATION...
TODAY WILL LIKELY BE A REPLAY OF THE LAST COUPLE OF DAYS, ONCE AGAIN.
EXPECT SOME CONVECTIVE SHOWER ACTIVITY IN THE MORNING, THEN THUNDERSTORMS
TO DEVELOP IN THE LATE MORNING TO EARLY AFTERNOON. THESE CAN LEAD TO
MVFR AND IFR CONDITIONS AT TIMES. HAVE ADDED PROB30 GROUPS TO ALL EAST
COAST TAF SITES FOR THE AFTERNOON HOURS. THIS TIME THERE IS A BETTER
CHANCE TSTMS COULD LINGER INTO THE EVENING HOURS SO LEFT VCTS IN THE
FORECAST FOR THE EVENING HOURS ALSO. WINDS WILL BE LIGHT AND VARIABLE
THIS MORNING AND PICK UP OUT OF THE SOUTHEAST MID TO LATE MORNING AROUND
10 KTS WITH A CHANCE OF A SOUTHWEST SEA BREEZE OF 5 T0 10 KNOTS AT APF
IN THE MID TO LATE AFTERNOON FOR A COUPLE OF HOURS.
PREV DISCUSSION... /ISSUED 416 AM EDT WED MAY 1 2013/
.WET WEATHER CONTINUES OVER SOUTH FLORIDA THROUGH EARLY THIS WEEKEND...
.SOME STRONG STORMS POSSIBLE TODAY AND AGAIN THURSDAY OVER SOUTH FLORIDA...
SHORT TERM...
LOW PRESSURE OVER THE WESTERN ATLANTIC WATERS WILL MOVE EAST TODAY
AS A MID TO UPPER LEVEL LOW OVER THE SOUTHERN GULF COAST STATES
MOVES SOUTHEAST INTO THE NORTHERN GULF OF MEXICO. THIS WILL ALLOW
FOR A TROUGH OF LOW PRESSURE OVER CENTRAL FLORIDA TO MOVE SOUTH INTO
THE LAKE OKEECHOBEE REGION TODAY KEEPING THE STEERING FLOW IN A
SOUTH TO SOUTHWEST DIRECTION OVER SOUTH FLORIDA. SO THE DEEP
TROPICAL MOISTURE WILL CONTINUE TO WORK INTO THE AREA FROM THE SOUTH
ALLOWING FOR SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. THE
STORMS WILL ALSO BE SLOW MOVERS TODAY LEADING TO HEAVY RAINFALL OVER
SOUTH FLORIDA. SO WILL CONTINUE TO MENTION THE HEAVY RAINFALL IN THE
ZONES FOR TODAY OVER SOUTH FLORIDA.
THE TROUGH OF LOW PRESSURE WILL REMAIN NEARLY STATIONARY TONIGHT
INTO THURSDAY...AS THE MID TO UPPER LEVEL LOW MOVES SLOWLY
SOUTHEAST INTO THE EASTERN GULF OF MEXICO. A SURFACE LOW WILL
ALSO DEVELOP IN THE EASTERN GULF OF MEXICO ON THURSDAY WHICH WILL
HELP KEEP THE SOUTH TO SOUTHWEST STEERING FLOW OVER SOUTH FLORIDA
ALONG WITH THE DEEP TROPICAL MOISTURE. SO WILL CONTINUE THE
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS OVER SOUTH FLORIDA
FOR THURSDAY ALONG WITH THE HEAVY RAINFALL WORDING.
THE 500 MB TEMPS WILL ALSO COOL OFF A BIT FROM AROUND -10C THIS
MORNING TO -12C TO -13C ON THURSDAY. THIS WILL ALLOW FOR SOME STRONG
STORMS OVER SOUTH FLORIDA TODAY...AND STRONG TO EVEN SEVERE STORMS
(WITH POTENTIAL FOR MORE THAN THE ORDINARY DEPENDING HOW MUCH
SURFACE HEATING WE END UP GETTING) ON THURSDAY OVER SOUTH FLORIDA.
ALTHOUGH THE PRIMARY THREAT FROM THE STORMS WILL CONTINUE TO BE
FLOODING POTENTIAL...SECONDARY THREATS FROM THE STORMS WILL BE GUSTY
WINDS...HAIL...AND FREQUENT LIGHTING STRIKES.
THE LOW OVER THE EASTERN GULF OF MEXICO WILL SLOWLY MOVE EAST ON
FRIDAY TOWARDS SOUTH FLORIDA...AS THE TROUGH OF LOW PRESSURE
REMAINS OVER SOUTH FLORIDA. THIS WILL CONTINUE TO KEEP THE DEEP
TROPICAL MOISTURE IN PLACE OVER SOUTH FLORIDA ON FRIDAY. SO WILL
CONTINUE THE SCATTERED TO NUMEROUS POPS OVER THE AREA FOR FRIDAY
ALONG WITH THE HEAVY RAINFALL WORDING.
LONG TERM...
THE LOW WILL MOVE EAST OVER SOUTH FLORIDA ON SATURDAY BEFORE
MOVING INTO THE WESTERN ATLANTIC WATERS ON SUNDAY. THIS WILL KEEP
THE AREA IN THE DEEP TROPICAL MOISTURE ON SATURDAY...BEFORE
ALLOWING FOR SOME DRIER AIR TO WORK INTO THE AREA FROM THE WEST ON
SUNDAY. THEREFORE...THE POPS ON SATURDAY WILL BE IN THE SCATTERED
RANGE OVER SOUTH FLORIDA WHILE ON SUNDAY THE POPS WILL BE IN SLIGHT
CHANCE TO LOW END CHANCE.
FOR EARLY NEXT WEEK...THE DRIER WEATHER WILL CONTINUE TO WORK INTO
THE AREA FROM THE NORTH AND WEST. SO THE WEATHER SHOULD BE DRY
OVER SOUTH FLORIDA FOR EARLY NEXT WEEK...AND WILL REMOVE THE SHOWER
AND THUNDERSTORM WORDING OVER SOUTH FLORIDA FOR EARLY NEXT WEEK.
HOWEVER...THERE REMAINS QUITE A BIT OF UNCERTAINTY AMONG THE MODELS
AND THIS OUTLOOK COULD CHANGE WITH THE WET PERIOD EITHER ENDING
EARLIER THAN SUNDAY OR LATER THAN ANTICIPATED INTO EARLY NEXT WEEK.
MARINE...
THE WINDS OVER SOUTH FLORIDA TODAY INTO THURSDAY WILL BE FROM THE
EAST TO SOUTHEAST AT 10 KNOTS OR LESS...BEFORE INCREASING TO
BREEZY CONDITIONS BY EARLY THIS WEEKEND FROM THE SOUTHERLY
DIRECTION. AT THE SAME TIME...A NORTHEAST SWELL OF 2 TO 3 FEET
WILL ALSO CONTINUE TO AFFECT THE PALM BEACH WATERS OF SOUTH
FLORIDA. THIS WILL ALLOW FOR THE SEAS TO REMAIN BELOW 6 FEET IN
THE ATLANTIC WATERS TODAY INTO THURSDAY...BEFORE INCREASING TO 7
FEET BY FRIDAY IN THE PALM BEACH WATERS. FOR THE GULF SIDE...THE
SEAS WILL REMAIN BELOW 6 FEET TODAY INTO EARLY THIS WEEKEND.
FIRE WEATHER...
THE RELATIVE HUMIDITIES WILL REMAIN ABOVE THE 35 PERCENT CRITICAL
VALUE EACH DAY OVER SOUTH FLORIDA THROUGH END OF THIS WEEK...DUE
TO THE TROPICAL MOISTURE REMAINING OVER THE AREA. SO NO PROBLEMS
ARE EXPECTED WITH THE FIRE WEATHER OVER SOUTH FLORIDA.
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1027 PM EDT THU MAY 2 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EDT THU MAY 2 2013
AN UPPER TROUGH OF LOW PRESSURE OVER THE GREAT PLAINS WILL DEEPEN
INTO A CLOSED UPPER LOW AND TRACK INTO THE MID MISSISSIPPI VALLEY BY
SATURDAY AND ACROSS TENNESSEE AND THE DEEP SOUTH SUNDAY AND MONDAY.
IT WILL MOVE OFF THE MID ATLANTIC COAST BY THE MIDDLE OF NEXT WEEK
AND HIGH PRESSURE WILL REBUILD ACROSS OUR REGION. THIS SYSTEM WILL
BRING INCREASING CHANCE OF SHOWERS NEXT FEW DAYS...ESPECIALLY WEST
AND SOUTH.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1007 PM EDT THU MAY 2 2013
MAIN CHANGE OVER THE LAST SEVERAL UPDATES HAS BEEN TO TAILOR BACK
POPS...ESPECIALLY ACROSS THE WESTERN COUNTIES WHERE ONLY A FEW
ISOLATED THUNDERSTORMS ARE MOVING THROUGH. BELIEVE HRRR HAS THE
BEST HANDLE ON POPS TONIGHT INTO FRIDAY AND LEANED TOWARD THIS
GUIDANCE. AT THIS RATE BULK OF PRECIP WILL NOT REACH CENTRAL
INDIANA UNTIL AT LEAST LATE MORNING FRIDAY...IF NOT LATER.
PREVIOUS DISC FOLLOWS...
RADAR HAS SHOWN AND INCREASE TO SHOWERS AND THUNDERSTORMS ACROSS
ILLINOIS THIS AFTERNOON AS CAPES HAVE BEEN RUNNING FROM 1500 TO 2000
J/KG. SOME OF THESE MAY SPREAD INTO FAR WESTERN SECTIONS THIS
EVENING AS AIRMASS IS SOMEWHAT UNSTABLE THERE. FATHER EAST WILL
DOWNPLAY RAIN CHANCES SOME AS MODELS HAVE TENDED TO BE TOO QUICK IN
SPREADING RAIN EAST TOO MUCH. LAPS SHOWS CAPES FROM INDY AND
EASTWARD NO MORE THAN 200 J/KG AND SOME OF THE PREVIOUS MODELS
INDICATED THAT IT COULD BE RAINING MUCH OF TODAY HERE AS WELL.
FOR NOW WILL MENTION HIGH CHANCE POPS FAR WEST...AND SLIGHT CHANCES
FROM INDY AND WESTWARD LATER TONIGHT. WHILE MOST EASTERN AREAS
SHOULD REMAIN DRY. OVERNIGHT LOWS WILL BE IN THE UPPER 50S TO LOWER
60S WHICH IS CLOSE TO PERSISTENCE.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 332 PM EDT THU MAY 2 2013
FORECAST FOCUS CONTINUES TO BE ON RAIN CHANCES FRIDAY...AND OVER THE
WEEKEND. MODELS DEEPEN THE UPPER TROUGH OVER THE PLAINS INTO A
CLOSED UPPER LOW AND TRACK IT TOWARDS SOUTHERN TENNESSEE AND
NORTHERN MISSISSIPPI. MODELS HAVE TRENDED A LITTLE FARTHER SOUTH
WITH THE TRACK...ESPECIALLY THE GFS. AS A RESULT...IT LOOKS LIKE THE
HEAVIEST RAINS WILL BE ACROSS OUR SOUTH AND ANY RAIN THAT MAKES IT
INTO OUR NORTHEAST WILL BE LIGHT.
ON FRIDAY WILL MENTION LIKELY POPS...FAR WEST...CHANCE POPS
ELSEWHERE...BUT DRY OR SLIGHT CHANCE POPS FAR EAST. WENT CLOSER TO
SLIGHTLY WARMER MET TEMPERATURES EAST AS THERE WILL STILL BE SOME
SUN.
THERE WILL BE BETTER CHANCES OF SHOWERS OVER THE WEEKEND CENTRAL AND
SOUTH AS THE UPPER LOW MOVES A LITTLE CLOSER. WENT WITH LIKELY POPS
FROM INDY AND SOUTH AND WEST AND CHANCE POPS ELSEWHERE. WENT CLOSE
TO A MOS BLEND ON TEMPERATURES. HIGH TEMPERATURES COULD BE A LITTLE
WARMER ACROSS OUR NORTHEAST...BECAUSE PRECIPITATION THERE WILL BE
SCATTERED AT BEST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 335 AM EDT THU MAY 2 2013
ENSEMBLES ARE SHOWING BETTER AGREEMENT ON A LARGE UPPER LOW SLOWLY
PASSING ACROSS THE TENNESSEE VALLEY FROM WEST TO EAST DURING THE
LONG TERM. SURFACE LOWS ARE STILL SHOWING QUITE A BIT OF SCATTER
SUNDAY NIGHT BUT SEEM TO COME INTO BETTER AGREEMENT BY MONDAY NIGHT
ON A LOCATION SOUTHEAST OF INDIANA AND MOVING FURTHER EAST AND AWAY
FROM THE AREA BY MIDDAY TUESDAY. THIS SHOULD ALLOW FOR POPS TO DROP
TO SLIGHT CHANCE OR LESS FROM MONDAY NIGHT ON. DURING THE DAYS SOME
INSTABILITY MAKES ITS WAY INTO THE SOUTHERN COUNTIES SO INCLUDED A
SLIGHT CHANCE OF THUNDER AT THAT TIME. SUNDAY NIGHT AND MONDAY THERE
IS SUFFICIENT FORCING FROM THE PROXIMITY OF THE UPPER AND SURFACE
LOWS TO JUSTIFY HIGH CHANCE POPS ACROSS THE SOUTH WITH LOWER CHANCES
AS YOU HEAD NORTH. FOR TEMPERATURES GENERALLY WENT WITH
ALLBLEND...WITH A SLIGHT ADJUSTMENT DOWN FOR HIGHS ON MONDAY WITH
THE UPPER LOW TO THE SOUTH AND MOSTLY CLOUDY SKIES.
&&
.AVIATION /DISCUSSION FOR THE 03/03Z TAF UPDATE/...
ISSUED AT 1027 PM EDT THU MAY 2 2013
NO SIGNIFICANT CHANGES NECESSARY. PREVIOUS DISCUSSION FOLLOWS.
ISSUED AT 721 PM EDT THU MAY 2 2013
MAINLY VFR THROUGH THE PERIOD OUTSIDE OF SHOWERS/THUNDERSTORMS.
BOUNDARY IS NEARLY STATIONARY JUST TO OUR NORTHWEST/WEST WITH WEAK
LOW PRESSURE ALONG IT. THIS BOUNDARY HAS SERVED AS FOCUS FOR
SCATTERED CONVECTIVE DEVELOPMENT TO OUR WEST THIS AFTERNOON WITH
SLOW AND ERRATIC STORM MOTIONS IN AN UNSTABLE BUT VERY WEAKLY
SHEARED ENVIRONMENT. THESE STORMS ARE UNLIKELY TO IMPACT ANY SITE
BUT PERHAPS HUF...WHERE VCTS WILL BE CARRIED EARLY.
OVERNIGHT...SHOWERS COULD MAKE HUF/LAF BUT IN GENERAL EXPECTING JUST
AN INCREASE IN CLOUD COVER. WINDS WILL BECOME LESS THAN 10KT AT
IND...LIGHT AND VARIABLE AT THE OUTLYING SITES.
WILL CONTINUE WITH VCTS/CB MENTION TOMORROW AS THIS BOUNDARY SHOULD
MAKE SOME VERY SLOW EASTWARD PROGRESS. WINDS WILL BE 8-12KT TOMORROW
OUT OF THE SOUTHEAST.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SMF
SHORT TERM...JH
LONG TERM....CP
AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1013 PM EDT THU MAY 2 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 332 PM EDT THU MAY 2 2013
AN UPPER TROUGH OF LOW PRESSURE OVER THE GREAT PLAINS WILL DEEPEN
INTO A CLOSED UPPER LOW AND TRACK INTO THE MID MISSISSIPPI VALLEY BY
SATURDAY AND ACROSS TENNESSEE AND THE DEEP SOUTH SUNDAY AND MONDAY.
IT WILL MOVE OFF THE MID ATLANTIC COAST BY THE MIDDLE OF NEXT WEEK
AND HIGH PRESSURE WILL REBUILD ACROSS OUR REGION. THIS SYSTEM WILL
BRING INCREASING CHANCE OF SHOWERS NEXT FEW DAYS...ESPECIALLY WEST
AND SOUTH.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1007 PM EDT THU MAY 2 2013
MAIN CHANGE OVER THE LAST SEVERAL UPDATES HAS BEEN TO TAILOR BACK
POPS...ESPECIALLY ACROSS THE WESTERN COUNTIES WHERE ONLY A FEW
ISOLATED THUNDERSTORMS ARE MOVING THROUGH. BELIEVE HRRR HAS THE
BEST HANDLE ON POPS TONIGHT INTO FRIDAY AND LEANED TOWARD THIS
GUIDANCE. AT THIS RATE BULK OF PRECIP WILL NOT REACH CENTRAL
INDIANA UNTIL AT LEAST LATE MORNING FRIDAY...IF NOT LATER.
PREVIOUS DISC FOLLOWS...
RADAR HAS SHOWN AND INCREASE TO SHOWERS AND THUNDERSTORMS ACROSS
ILLINOIS THIS AFTERNOON AS CAPES HAVE BEEN RUNNING FROM 1500 TO 2000
J/KG. SOME OF THESE MAY SPREAD INTO FAR WESTERN SECTIONS THIS
EVENING AS AIRMASS IS SOMEWHAT UNSTABLE THERE. FATHER EAST WILL
DOWNPLAY RAIN CHANCES SOME AS MODELS HAVE TENDED TO BE TOO QUICK IN
SPREADING RAIN EAST TOO MUCH. LAPS SHOWS CAPES FROM INDY AND
EASTWARD NO MORE THAN 200 J/KG AND SOME OF THE PREVIOUS MODELS
INDICATED THAT IT COULD BE RAINING MUCH OF TODAY HERE AS WELL.
FOR NOW WILL MENTION HIGH CHANCE POPS FAR WEST...AND SLIGHT CHANCES
FROM INDY AND WESTWARD LATER TONIGHT. WHILE MOST EASTERN AREAS
SHOULD REMAIN DRY. OVERNIGHT LOWS WILL BE IN THE UPPER 50S TO LOWER
60S WHICH IS CLOSE TO PERSISTENCE.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 332 PM EDT THU MAY 2 2013
FORECAST FOCUS CONTINUES TO BE ON RAIN CHANCES FRIDAY...AND OVER THE
WEEKEND. MODELS DEEPEN THE UPPER TROUGH OVER THE PLAINS INTO A
CLOSED UPPER LOW AND TRACK IT TOWARDS SOUTHERN TENNESSEE AND
NORTHERN MISSISSIPPI. MODELS HAVE TRENDED A LITTLE FARTHER SOUTH
WITH THE TRACK...ESPECIALLY THE GFS. AS A RESULT...IT LOOKS LIKE THE
HEAVIEST RAINS WILL BE ACROSS OUR SOUTH AND ANY RAIN THAT MAKES IT
INTO OUR NORTHEAST WILL BE LIGHT.
ON FRIDAY WILL MENTION LIKELY POPS...FAR WEST...CHANCE POPS
ELSEWHERE...BUT DRY OR SLIGHT CHANCE POPS FAR EAST. WENT CLOSER TO
SLIGHTLY WARMER MET TEMPERATURES EAST AS THERE WILL STILL BE SOME
SUN.
THERE WILL BE BETTER CHANCES OF SHOWERS OVER THE WEEKEND CENTRAL AND
SOUTH AS THE UPPER LOW MOVES A LITTLE CLOSER. WENT WITH LIKELY POPS
FROM INDY AND SOUTH AND WEST AND CHANCE POPS ELSEWHERE. WENT CLOSE
TO A MOS BLEND ON TEMPERATURES. HIGH TEMPERATURES COULD BE A LITTLE
WARMER ACROSS OUR NORTHEAST...BECAUSE PRECIPITATION THERE WILL BE
SCATTERED AT BEST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 335 AM EDT THU MAY 2 2013
ENSEMBLES ARE SHOWING BETTER AGREEMENT ON A LARGE UPPER LOW SLOWLY
PASSING ACROSS THE TENNESSEE VALLEY FROM WEST TO EAST DURING THE
LONG TERM. SURFACE LOWS ARE STILL SHOWING QUITE A BIT OF SCATTER
SUNDAY NIGHT BUT SEEM TO COME INTO BETTER AGREEMENT BY MONDAY NIGHT
ON A LOCATION SOUTHEAST OF INDIANA AND MOVING FURTHER EAST AND AWAY
FROM THE AREA BY MIDDAY TUESDAY. THIS SHOULD ALLOW FOR POPS TO DROP
TO SLIGHT CHANCE OR LESS FROM MONDAY NIGHT ON. DURING THE DAYS SOME
INSTABILITY MAKES ITS WAY INTO THE SOUTHERN COUNTIES SO INCLUDED A
SLIGHT CHANCE OF THUNDER AT THAT TIME. SUNDAY NIGHT AND MONDAY THERE
IS SUFFICIENT FORCING FROM THE PROXIMITY OF THE UPPER AND SURFACE
LOWS TO JUSTIFY HIGH CHANCE POPS ACROSS THE SOUTH WITH LOWER CHANCES
AS YOU HEAD NORTH. FOR TEMPERATURES GENERALLY WENT WITH
ALLBLEND...WITH A SLIGHT ADJUSTMENT DOWN FOR HIGHS ON MONDAY WITH
THE UPPER LOW TO THE SOUTH AND MOSTLY CLOUDY SKIES.
&&
.AVIATION /DISCUSSION FOR THE 03/00Z TAFS/...
ISSUED AT 721 PM EDT THU MAY 2 2013
MAINLY VFR THROUGH THE PERIOD OUTSIDE OF SHOWERS/THUNDERSTORMS.
BOUNDARY IS NEARLY STATIONARY JUST TO OUR NORTHWEST/WEST WITH WEAK
LOW PRESSURE ALONG IT. THIS BOUNDARY HAS SERVED AS FOCUS FOR
SCATTERED CONVECTIVE DEVELOPMENT TO OUR WEST THIS AFTERNOON WITH
SLOW AND ERRATIC STORM MOTIONS IN AN UNSTABLE BUT VERY WEAKLY
SHEARED ENVIRONMENT. THESE STORMS ARE UNLIKELY TO IMPACT ANY SITE
BUT PERHAPS HUF...WHERE VCTS WILL BE CARRIED EARLY.
OVERNIGHT...SHOWERS COULD MAKE HUF/LAF BUT IN GENERAL EXPECTING JUST
AN INCREASE IN CLOUD COVER. WINDS WILL BECOME LESS THAN 10KT AT
IND...LIGHT AND VARIABLE AT THE OUTLYING SITES.
WILL CONTINUE WITH VCTS/CB MENTION TOMORROW AS THIS BOUNDARY SHOULD
MAKE SOME VERY SLOW EASTWARD PROGRESS. WINDS WILL BE 8-12KT TOMORROW
OUT OF THE SOUTHEAST.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SMF
SHORT TERM...JH
LONG TERM....CP
AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
702 PM CDT THU MAY 2 2013
.SYNOPSIS...
ISSUED AT 351 PM CDT THU MAY 2 2013
12Z UA ANALYSIS HAS 850MB LOWS ALONG THE KS/MO BORDER AND ANOTHER IN
WESTERN OKLAHOMA. A VERY STRONG 850MB THERMAL GRADIENT RAN FROM
MN/WI DOWN TO OKLAHOMA AND WEST TEXAS. SATELLITE TRENDS THROUGH MID
AFTERNOON SHOW THE LOW CLOUDS MAKING SLOW PROGRESS EASTWARD. RADAR
SHOWS THE MAIN RAIN SHIELD OVER CENTRAL AND NORTHEAST IOWA WITH
SCATTERED CONVECTION ACROSS ILLINOIS AND EASTERN IOWA.
18Z SFC ANALYSIS HAS WEAK LOWS FROM LOWER MICHIGAN BACK INTO
NORTHEAST ARKANSAS WITH THE FRONT CONNECTING ALL THE LOWS. DEW
POINTS ACROSS THE PLAINS AND PARTS OF THE UPPER MIDWEST WERE IN THE
20S AND 30S WITH 40S AND HIGHER FROM THE GREAT LAKES INTO THE LOWER
MISSISSIPPI VALLEY.
08
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM CDT THU MAY 2 2013
VERY DIFFICULT FCST. REFER TO THE CLIMATE SECTION FOR INFORMATION
REGARDING MAY SNOW FOR SOME LOCATIONS.
THE TRENDS WITH THE MODELS IS COLDER. THE MAIN PRECIPITATION SHIELD
IS ALONG AND BEHIND THE 850MB FRONT. THE RAP AND WRF TRENDS HAVE
THIS FRONT SLOWLY MOVING EAST TONIGHT. THUS RAIN WILL SLOWLY BREAK
OUT AND INCREASE IN AREAL COVERAGE DURING THE EVENING HOURS.
WBZ TEMPERATURES AND ACTUAL OBSERVATIONS SHOW TREMENDOUS EVAPORATIVE
COOLING WILL OCCUR ACROSS THE FAR NORTHWEST AND WESTERN PARTS OF THE
CWFA TONIGHT. FCST SOUNDINGS INDICATE RAIN BECOMING MIXED WITH AND
THEN CHANGING OVER TO SLEET/SNOW MIXTURE. THE OVERALL FORCING AND
WAA ALOFT IS SIGNIFICANT SO THERE WILL LIKELY BE ACCUMULATIONS ON
GRASSY SURFACES EVEN THOUGH THE GROUND IS QUITE WARM.
THEREFORE...WINTER WEATHER ADVISORIES HAVE BEEN RAISED FOR THE
WESTERN TWO ROWS OF COUNTIES FROM HWY 92 ON NORTH.
BUCHANAN...BENTON...IOWA...AND KEOKUK COUNTIES HAVE THE BEST CHANCE
AT SEEING POTENTIALLY HISTORIC SNOWFALL FOR MAY. THE HIGHEST
SNOWFALL AMOUNTS WILL BE IN THE WESTERN PARTS OF THESE COUNTIES.
SNOW/SLEET AMOUNTS THERE COULD RANGE FROM 1 TO 4 INCHES.
FURTHER EAST...ACROSS DELAWARE...LINN...JOHNSON...AND WASHINGTON
COUNTIES THE CHANGE OVER TO SLEET WILL OCCUR DURING THE EVENING. IN
THIS AREA MORE SLEET THAN SNOW IS EXPECTED WITH THE HIGHER AMOUNTS
IN THE WESTERN PARTS OF THESE COUNTIES. SNOW/SLEET AMOUNTS IN THIS
AREA COULD RANGE FROM A DUSTING TO 1 INCH.
THE OVERALL LARGE PICTURE SUGGESTS THE POTENTIAL FOR SOME SLEET AS
FAR EAST AS A DUBUQUE IOWA TO KAHOKA MISSOURI LINE DUE TO
EVAPORATIVE COOLING. IN THIS AREA ONLY TRACE AMOUNTS ARE EXPECTED.
ROUGHLY ALONG AND EAST OF THE MISSISSIPPI...SHOWERS WILL GIVE WAY TO
A WIDESPREAD RAIN AS THE WAA INCREASES.
FRIDAY...THE SNOW/SLEET MIXTURE IN THE FAR NORTHWEST/WEST PARTS OF
THE CWFA WILL CHANGE BACK TO ALL RAIN AS WARM AIR ALOFT MOVES INTO
THE AREA. ACROSS THE EASTERN CWFA THE OVERALL FORCING INCREASES AS A
SFC WAVE MOVES UP FROM THE SOUTH. ALTHOUGH NOT INCLUDED IN THE
FORECAST...THE LIFT TOOL SUGGESTS POSSIBLY SOME ISOLATED THUNDER
OVER THE FAR SOUTHEAST AND EASTERN PARTS OF THE CWFA AS STRONG
CONVERGENCE MOVES ALONG A THETA E GRADIENT.
08
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 351 PM CDT THU MAY 2 2013
RECORD COLD RAIN...SLEET...SNOW EVENT MAIN CHALLENGE THIS FORECAST.
OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH MAIN ISSUE THE
PHASING OF LATENT HEAT RELEASE AND STRONG EVAPORATIVE COOLING TO
DETERMINE WHAT FAR WESTERN SECTIONS RECEIVE SLEET AND SNOW TONIGHT.
VERIFICATION AT 18Z SUPPORTS FORCING AND THERMAL FIELDS OF 12Z NAM-
WRF AND HI-RES ECMWF. THIS SUPPORTS SOME ACCUMULATIONS OF SNOW AND
QUITE A BIT OF SLEET FAR WEST SECTIONS. HEAVY RAIN AND FORCING
TOOLS SUGGEST MOST OF AREA TO PICK UP 1.5 TO LOCALLY AROUND 2.5
INCHES OF TOTAL PRECIPITATION NEXT 2-3 DAYS WITH MOST FALLING
FRIDAY AND FRIDAY NIGHT. STRATIFORM NATURE AND AMOUNTS OVER LONGER
TIME PERIOD SUPPORT MINOR RIVER ISSUES ON SOME RIVERS.
FRIDAY NIGHT...KEPT CATEGORICAL POPS WITH DEEPLY OCCLUDING AND
MATURING RAIN OF UPPER LOW TO DEPOSIT MOSTLY 1/3 TO 2/3 OF AN INCH
WITH HEAVIEST OVER SW 1/2 TO 2/3 OF AREAL TEMPERATURES WITH MILDER
AIR FROM EAST TO ALLOW TEMPERATURES TO BE NEARLY STEADY WITH LOWER
50S EAST TO MID/UPPER 40S FAR WEST.
SATURDAY AND SUNDAY...MINOR CHANGES MADE. CONSIDERABLE CLOUDS WITH
PERIODS OF LIGHT RAIN SATURDAY AND SATURDAY AND VERY LIGHT RAIN
SUNDAY. A QUARTER INCH OR LESS ON SATURDAY MOST LOCATIONS WITH
SPOTTY VERY LIGHT AMOUNTS SUNDAY. TEMPERATURES COOL WITH MOSTLY
LOWER TO MIDDLE 60S AND MINS SATURDAY NIGHT IN THE MID/UPPER 40S.
NICHOLS
DAYS 4 THROUGH 7...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT THROUGH MONDAY NIGHT THE DEEP UPPER LOW GRADUALLY
SHIFTS SOUTHEAST...AND A SURFACE RIDGE BUILDS INTO THE AREA TO CAUSE
OUR SCATTERED SHOWERS TO SLOWLY DIMINISH IN COVERAGE...SO THAT BY
MONDAY NIGHT WE SHOULD BE COMPLETELY DRY. TEMPERATURES TO REMAIN
BELOW NORMAL WITH LOWS IN THE 40S. MONDAY HIGHS ARE CURRENTLY
FORECAST TO RISE INTO THE UPPER 60S...BUT IT TOO MUCH CLOUD COVER IS
LINGERING WILL HAVE TO LOWER THESE VALUES.
TUESDAY AND TUESDAY NIGHT THE SURFACE RIDGE SLOWLY SHIFTS EAST
ACROSS THE AREA...PRODUCING MAINLY DRY CONDITIONS AND GRADUALLY
WARMING TEMPERATURES. AM CARRYING SOME DAYTIME SLIGHT CHANCE POPS
IN THE SOUTHWEST CLOSEST TO THE LINGERING PLUME OF MOISTURE WHERE WE
MIGHT GET SOME DIURNALLY DRIVEN SHOWERS. HIGHS TUESDAY SHOULD GET
APPROACH 70 WITH 850MB TEMPERATURES GRADUALLY WARMING AS WELL.
TUESDAY NIGHT MINS TO MODERATE TO AROUND 50.
WEDNESDAY AND THURSDAY QUITE A BIT OF UNCERTAINTY RE-ENTERS THE
FORECAST. WE WILL BE IN A SPLIT FLOW WITH A NORTHERN STREAM MAINLY
AFFECTING SOUTHERN CANADA AND THE FAR NORTHERN CONUS...AND THE
SOUTHERN STREAM MAINLY AFFECTING THE SOUTHERN CONUS. MODELS ARE
DIVERGING IN THE HANDLING OF A SHORTWAVE THAT MOVES THROUGH THE
NORTHERN STREAM...AND HOW MUCH IT PHASES WITH A CUT OFF LOW IN THE
SOUTHERN STREAM OVER THE SOUTHWEST CONUS. THE ECMWF IS FASTER AND
IS PHASING IT MORE...AND DRAGGING MORE MOISTURE UP INTO THE
AREA...PRODUCING PRECIPITATION BEGINNING WEDNESDAY NIGHT. THE GFS
IS SLOWER AND PHASES IT LESS...AND DOES NOT BRING PRECIPITATION INTO
THE AREA UNTIL THURSDAY NIGHT. THUS...WHILE I AM CARRYING SOME
SLIGHT CHANCE POPS BEGINNING ON WEDNESDAY...THESE ARE MORE FOR A
CONTINUATION OF THE DIURNAL SHOWERS DURING THE DAY WITH THE
GRADUALLY INCREASING MOISTURE. AM BRINGING IN SOME LOW CHANCE POPS
FOR THURSDAY IN ASSOCIATION WITH THE NEW SHORTWAVE. TEMPERATURES TO
CONTINUE TO WARM THROUGH AT LEAST WEDNESDAY NIGHT...WITH HIGHS ON
WEDNESDAY INTO THE LOWER 70S. THURSDAY STILL FAIRLY WARM IN THE
FORECAST BUT THIS MAY NEED TO BE LOWERED IF PRECIPITATION MOVES INTO
THE AREA SOONER.
LE
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 655 PM CDT THU MAY 2 2013
AN AREA OF RAIN SHOWERS CONTINUES TO SPREAD NORTH AFFECTING
LOCATIONS ALONG AND TO THE WEST OF THE MISSISSIPPI RIVER IN
EASTERN IOWA. PERIODS OF RAIN WITH THIS ACTIVITY WILL CONTINUE FOR
KBRL...WITH EVENTUAL DEVELOPMENT INTO THE KMLI AND KDBQ AREAS
EXPECTED LATE THIS EVENING. JUST A BIT FURTHER WEST A MIX OF
WINTRY PRECIPITATION HAS BEEN REPORTED WITH SOME SLEET AND
SNOW...AND A BAND OF SNOW CONTINUES TO EDGE EAST FROM CENTRAL
IOWA. THIS MIXED PRECIPITATION AND POTENTIAL FOR SLEET OR SNOW
ACCUMULATIONS IS MOST LIKELY TO AFFECT KCID TONIGHT INTO FRIDAY
MORNING...WITH SOME POTENTIAL BUT LESS CONFIDENCE FOR KDBQ. A
RETURN TO LIQUID PRECIPITATION IS THEN FORECAST BY MID FRIDAY
MORNING.
MVFR TO IFR CONDITIONS ARE EXPECTED WITH A DETERIORATION TO IFR OR
LIFR CEILINGS OVERNIGHT INTO FRIDAY MORNING.
STOFLET
&&
.CLIMATE...
ISSUED AT 351 PM CDT THU MAY 2 2013
MAY SNOWFALL IN IOWA IS RARE.
A VERY QUICK LOOK BACK AT PAST WEATHER RECORDS SUGGESTS THAT THE
LAST TIME A FAIRLY WIDESPREAD SNOW OCCURRED IN MAY ACROSS IOWA WAS
IN 1966. BELOW IS WHEN MEASURABLE SNOW AND/OR SLEET FELL IN MAY
FOR SELECTED SITES.
CEDAR RAPIDS #1 (MARION)...
0.2 INCHES 05/01/1997 FELL AS SLEET
0.3 INCHES 05/11/1966
DUBUQUE IOWA...
3.1 INCHES 05/01/1966
1.0 INCHES 05/07-08/1960
IOWA CITY WWTP...
0.2 INCHES 05/05/1944
MOLINE ILLINOIS...
0.3 INCHES ON 05/03/1935
TRACE ON 05/06/1989
TRACE ON 05/22/1917*
* LATEST RECORDED SNOWFALL ON RECORD
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY UNTIL 10 AM CDT FRIDAY FOR BENTON-
BUCHANAN-IOWA-KEOKUK.
WINTER WEATHER ADVISORY UNTIL 8 AM CDT FRIDAY FOR DELAWARE-
JOHNSON-LINN-WASHINGTON.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...NICHOLS/LE
AVIATION...STOFLET
CLIMATE...08
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
116 AM EDT WED MAY 1 2013
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 432 PM EDT TUE APR 30 2013
WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD MID/UPPER LEVEL TROUGH
OVER THE NW CONUS RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE
NRN GREAT LAKES. A VIGOROUS SHORTWAVE IN THIS SW FLOW ALOFT WAS
LIFTING NORTH INTO NW ONTARIO. AT THE SFC...LOW PRES WAS LOCATED
OVER NW ONTARIO WITH A COLD FRONT EXTENDING SOUTH INTO FAR WRN LAKE
SUPERIOR AND NW WI. A WARM FRONT WAS DRAPED ACROSS NCNTRL AND NE WI.
BULGE OF WARM DRY AIR AT AROUND 850 MB AS NOTED ON 12Z GRB SNDG AND
LATEST RAPID RUC SNDGS AT KIMT HAS PRODUCED SEVERAL HUNDRED J/KG OF
CIN....KEEPING ATMOSPHERE CAPPED ENOUGH TO PROHIBIT SHOWERS FROM
FORMING OVER MUCH OF THE FCST AREA SO FAR THIS AFTERNOON. JUST IN
LATEST RADAR VOLUME SCAN STARTING TO SEE A FEW SHOWERS POPPING OVER
HOUGHTON COUNTY BUT WITH ONLY AROUND 200-300 J/KG OF MLCAPE NOT
REALLY EXPECTED MUCH IN WAY OF THUNDER.
AS MODELS SHOW FRONT MOVG SLOWLY EAST INTO CENTRAL FCST AREA...RAP
RUC SNDGS FOR KIMT SUGGESTS CAP ALOFT MAY ERODE JUST ENOUGH TO ALLOW
FOR SOME ISOLD TO SCT SHRA/TSRA TO FORM TOWARD SUNSET OVER CNTRL
FCST AREA. INCREASING 800-700 MB FGEN IN RESPONSE TO RIGHT ENTRANCE
REGION FORCING IN 140+ KT 3H JET OVER NRN PLAINS AND WRN ONTARIO
WILL BE MAIN DRIVING FORCE FOR BAND OF RAIN WHICH MODELS PROJECT TO
FORM LATE THIS EVENING AND EARLY OVERNIGHT OVER CENTRAL PORTION OF
THE FCST AREA. THIS BAND OF PCPN IS THEN PROGGED BY MODELS TO SHIFT
OVER THE WRN CWA LATE TONIGHT INTO WED AS BEST FGEN FORCING SHIFTS
WEST. LOWS TONIGHT WILL BE IN THE 40S UNDER MOSTLY CLOUDY SKIES.
MODEL AVG QPF INDICATES THAT PORTIONS OF GOGEBIC AND ONTONAGON
COUNTIES COULD SEE UP TO QUARTER INCH OF PCPN LATE TONIGHT INTO
WEDNESDAY. COLDER AIR (8H TEMPS DROPPING BLO 0C )SEEPING INTO THE
WRN CWA COULD CAUSE SOME SNOW TO MIX IN WITH RAIN BY LATE WED
AFTERNOON AS TEMPS FALL INTO THE MID TO UPPER 30S TOWARD EVENING.
N-NW ONSHORE FLOW OFF COOL LAKE SUPERIOR ALONG CLOUDY SKIES WILL
RESULT IN MAX TEMPS ON THE LOWER END OF MODEL GUIDANCE FOR WEDNESDAY
WITH HIGHS RANGING FROM THE LOWER TO MID 40S ALONG LAKE SUPERIOR TO
GENERALLY THE LOWER TO MID 50S EAST AND SCNTRL.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 432 PM EDT TUE APR 30 2013
FORECAST CONTINUES TO DEAL WITH THE UPPER TROUGH DEVELOPING IN THE
IN THE NORTHERN PLAINS AND WHAT HAPPENS TO IT AS IT CUTS OFF AROUND
THE END OF THIS WEEK AND DRIFTS THIS WEEKEND.
TO START THE PERIOD...THE FORECAST CONCERN IS THE STALLED 850MB
FRONT STRETCHING FROM NORTHERN LAKE SUPERIOR THROUGH SOUTHEAST
MINNESOTA AND INTO THE CENTRAL PLAINS AS THE UPPER TROUGH SLOWLY
SHIFTS EAST THROUGH THE NORTHERN PLAINS. THE POSITION OF THE FRONT
WILL BE THE MAIN CONCERN...AS THERE WILL LIKELY BE AN AXIS OF HIGHER
PRECIPITATION AMOUNTS ALONG THIS FRONT. LATEST TRENDS IN THE MODELS
IS THAT THE 850MB FRONT IS A LITTLE FARTHER WEST AND THE HEAVIEST
PRECIPITATION LOOKS TO FALL SOMEWHERE EAST OF DULUTH AND WEST OF A
LINE FROM BARAGA TO WATERSMEET. WITH THE AREA THE 850-700MB WAA/FGEN
IS LINING UP...WOULD THINK THAT THE BEST PRECIPITATION WOULD BE OVER
THE FAR WESTERN CWA...BUT STILL EXPECT LIGHTER VALUES OVER THE REST
OF THE WESTERN CWA. THIS MATCHES UP WELL WITH THE 09Z SREF QPF
PROBABILITIES. THERE WILL PROBABLY BE SOME SHOWERS OVER THE
CENTRAL U.P. BUT THE AMOUNTS SHOULD BE LIGHTER THAN SEEN OVER THE
WEST. UNFORTUNATELY...THIS PRECIPITATION WON/T HELP THE ALREADY
SWOLLEN RIVERS AND STREAMS OVER FAR WESTERN UPPER MICHIGAN AND WILL
HEIGHTEN THE AFFECTS IN THE HWO AND INDIVIDUAL RIVER PRODUCTS.
BASED OFF THE THERMAL FIELDS AND BUFKIT SOUNDINGS...IT APPEARS THAT
IT WILL MAINLY BE SNOW OVER THE FAR WESTERN CWA...WITH A RAIN/SNOW
MIX OVER THE WEST-CENTRAL...BEFORE CHANGING TO ALL RAIN EAST OF A
LINE FROM NEGAUNEE TO CRYSTAL FALLS. THERE STILL REMAINS SOME
UNCERTAINTY IN THE P-TYPE TYPE AS THEY HAVE BEEN VARYING IN HOW FAR
WEST THE WARM AIR ALOFT SLIDES. NAM AND OUR REGIONAL WRF-ARW DO HINT
AT A SOME DRYING ALOFT WHICH COULD LIMIT ICE CRYSTAL POTENTIAL OVER
THE WEST...WHICH WILL BE SOMETHING TO WATCH. IF THE PRECIP STAYS AS
SNOW OVER THE WEST HALF OF GOGEBIC AND WESTERN ONTONAGON
COUNTY...THEY COULD SEE SIGNIFICANT LATE SEASON
SNOWFALL...ESPECIALLY ON THE COLDER SURFACES AND HIGHER TERRAIN.
CURRENTLY HAVE BORDERLINE WARNING SNOW AMOUNTS FOR WEDNESDAY NIGHT
INTO THURSDAY MORNING...SO WILL CONTINUE TO MENTION IN THE HWO. IF
CONFIDENCE WAS A LITTLE GREATER ON EXACT LOCATION OF THE HEAVIEST
QPF...AND THERE WEREN/T SEVERAL OTHER FLOOD WARNING/WATCH/ADVISORY
PRODUCTS OUT FOR GOGEBIC COUNTY...COULD HAVE ISSUED A WINTER
STORM WATCH.
THE UPPER TROUGH STARTS THE CUTOFF PROCESS THURSDAY NIGHT INTO
FRIDAY MORNING...WHICH WILL ALLOW THE FLOW ALOFT TO BECOME MORE
SOUTHEASTERLY AND SHIFT THE FRONT WEST. THIS WILL PULL WARMER AIR
INTO THE AREA AND SHOULD LIMIT THE SNOW POTENTIAL. BUT THIS WARMER
AIR MOVING IN ALOFT WILL LEAD COLD AIR TRAPPED NEAR THE SURFACE.
THIS HAS BEEN HINTED AT OVER THE LAST DAY...BUT HAVE CONCERNS THAT
THE GROUND TEMPERATURES WON/T GO BELOW FREEZING. THUS...WILL JUST
HAVE A SLIGHT CHANCE MENTION FOR AREAS WITH RAIN AND TEMPS BELOW 31
DEGREES. WITH THE DIFFERENCES IN THE HANDLING OF THE TROUGH CUTTING
OFF...THERE ARE DIFFERENCES IN THE MOVEMENT OF THE FRONT...SO WILL
GO WITH A BROADER POPS HEADING INTO FRIDAY...BUT THE BEST FOCUS
OVER THE SOUTHWEST HALF.
THE WEEKEND INTO EARLY NEXT WEEK STILL REMAINS UP IN THE AIR DUE TO
THE DIFFERENCES IN THE LOCATION OF THE UPPER LOW. 00Z ECMWF IS
CONSISTENT WITH IT/S PREVIOUS RUN AND IS FARTHEST TO THE NORTH. 12Z
GFS CONTINUES IT/S TREND OF BEING WELL TO THE SOUTH OF THE AREA
/CENTRAL MISSISSIPPI VALLEY/...WHILE THE 12Z GEM HAS IT IN THE
GREAT LAKES. AS WITH YESTERDAY...WILL FOLLOW A GENERAL CONSENSUS
INTO NEXT WEEK AS THE LOCATION OF THE LOW HAS LARGE IMPLICATIONS ON
TEMPERATURES AND PRECIPITATION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 115 AM EDT WED MAY 1 2013
A COLD FRONT WILL PUSH THROUGH ALL THREE TAF SITES OVERNIGHT AND
WEDNESDAY AFTERNOON. THIS WILL BRING RAIN SHOWERS TO ALL THREE TAF
SITES THROUGHOUT THE NIGHT TONIGHT AND INTO THE DAY ON WEDNESDAY.
RADAR SHOWS PRECIPITATION MOVING INTO SOUTHWESTERN UPPER MICHIGAN AS
OF 430Z. LATER IN THE DAY WEDNESDAY...WITH COLD AIR FILTERING IN
BEHIND THE FRONT...THE WESTERN TAF SITES KCMX/KIWD WILL START TO SEE
A CHANGEOVER TO RAIN/SNOW MIX. KIWD WILL GRADUALLY CHANGE TO ALL
SNOW AFTER 00Z 5/2. EXPECT THE SNOW TO BECOME MODERATE AFTER ABOUT
3Z WHEN THE BETTER FORCING ARRIVES ALOFT. AS A RESULT....HAVE IWD
DIMINISHING TO LIFR CONDITIONS TOWARDS THE END OF THE TAF PERIOD.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 432 PM EDT TUE APR 30 2013
NO GALES SEEN IN THIS FORECAST PERIOD. WINDS WILL GET UP TO 30 KNOTS
ACROSS THE EASTERN PORTION OF LAKE SUPERIOR EARLY THIS EVENING WITH
TIGHTENING GRAD AHEAD OF COLD FRONT. WINDS THEN STAY GEENRALLY AT OR
BELOW 25 KNOTS FOR THE REST OF THE PERIOD.
&&
.HYDROLOGY...
ISSUED AT 432 PM EDT TUE APR 30 2013
ANOTHER DAY OF WARM TEMPERATURES HAS CONTINUED THE SNOW MELT AND
THE RISING RIVER LEVELS ACROSS THE AREA. FORTUNATELY...RAINFALL
AMOUNTS OVER THE LAST COUPLE OF DAYS HAVE BEEN FAIRLY LIGHT AND HAS
KEPT THE FLOODING CONCERNS TO THE SNOW MELT. THE MAIN SNOW LEFT
OVER THE AREA IS OVER THE HIGHER TERRAIN LOCATIONS OVER THE
WEST...WHERE VALUES ARE IN THE 3-15 INCH RANGE. THE WARM
TEMPERATURES TONIGHT SHOULD CONTINUE THE MELT...BUT IS SHOULD BE
SLOWED AS TEMPERATURES FALL BEHIND A COLD FRONT THAT MOVES
THROUGH TONIGHT. THIS FRONT WILL PRODUCE ISOLATED/SCATTERED SHOWERS
BUT WIDESPREAD MODERATE-HEAVY RAINFALL AMOUNTS ARE NOT EXPECTED.
ATTENTION THEN TURNS TO AN UPPER LEVEL FRONT THAT STALLS OVER FAR
WESTERN UPPER MICHIGAN WEDNESDAY THROUGH THURSDAY. THIS HAS THE
POTENTIAL TO PRODUCE OVER AN INCH OF QPF OVER THE WESTERN THIRD OF
UPPER MICHIGAN THROUGH THURSDAY NIGHT. THE HEAVIEST
AMOUNTS...POTENTIALLY EXCEEDING 1.5 INCHES WILL BE OVER WESTERN
ONTONAGON AND WESTERN GOGEBIC COUNTIES. WITH THE COLDER
TEMPERATURES...THERE IS UNCERTAINTY IN THE THE EXACT PRECIPITATION
TYPE...BUT IT LOOKS LIKE A RAIN/SNOW MIX OVER THE WEST AND MAINLY
SNOW OVER THE FAR WEST. THIS PRECIPITATION WILL NOT HELP MATTERS
OVER THE WESTERN CWA...WHERE MANY RIVERS/STREAMS/CREEKS ARE
EXCEEDING BANKFULL OR FLOODING. THIS PRECIPITATION WILL DEFINITELY
NEED TO BE WATCHED OVER THE NEXT DAY OR TWO TO PIN DOWN AMOUNTS AND
TYPES...WHICH WILL HELP DETERMINE THE TIME THEY WILL INFLUENCE THE
RIVERS. ELSEWHERE...THE TIME LAGGED FLOW INCREASES FROM THE SNOW
MELT WILL LEAD TO CONTINUED RISES OVER THE NORTH CENTRAL
TRIBUTARIES OF THE ESCANABA AND MICHIGAMME RIVERS. THESE AREAS MAY
SEE FLOODING OVER THE COMING DAYS.
IN THE NEAR TERM...THE GREATEST FLOODING THREAT IS FOR THE RIVERS
IN WEST AND CENTRAL UPPER MICHIGAN. SEVERAL RIVER FLOOD
WARNING/WATCH/ADVISORIES ARE ALREADY IN PLACE...ALONG WITH SOME
AERIAL FLOOD ADVISORIES. FOR COMPLETE DETAILS...SEE THE LATEST RIVER
FLOOD WATCHES...WARNINGS AND ADVISORIES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR MIZ009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...SRF
AVIATION...MCD
MARINE...VOSS
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1003 PM CDT THU MAY 2 2013
.UPDATE...
LIGHT SNOW CONTINUES TO FALL ACROSS NW WISCONSIN THIS EVENING. I
UPDATED THE FORECAST THROUGH THE REST OF TONIGHT. THE SNOW WILL
LIKELY CONTINUE THROUGH THE REST OF THE NIGHT. THERE HAS BEEN A
LITTLE BIT OF A LULL THIS EVENING...BUT THE MODELS AND RADAR
SUGGEST THE SNOW/PCPN RATES MAY PICK UP A BIT AGAIN AFTER
MIDNIGHT. THE LATEST NAM12 SOUNDINGS AND HRRR MODEL RUNS SUGGESTED
THE FREEZING RAIN MIGHT NOT BEGIN TO MOVE INTO NW WISCONSIN UNTIL
VERY LATE TONIGHT...SO I DELAYED ITS ARRIVAL.
THE MAIN CHALLENGE WITH THIS UPDATE WAS TO DETERMINE IF THE WINTER
WEATHER HEADLINES ARE STILL GOOD. MUCH OF NW WISCONSIN STILL HAS A
WINTER STORM WARNING WHICH IS IN EFFECT THROUGH FRIDAY MORNING.
WHILE ONLY LIGHT TO MODERATE SNOW IS EXPECTED THROUGH FRIDAY
MORNING...THE THREAT OF FREEZING RAIN LATER TONIGHT AND FRIDAY
MORNING HAS ME LEANING ON MAINTAINING THE CURRENT HEADLINES. THERE
IS A CHANCE THAT SIGNIFICANTLY MORE FREEZING RAIN COULD FALL THAN
FORECASTED. I THINK IT WOULD BE BEST TO FIRST MONITOR THE CHANGE
OVER TO MIXED PCPN LATER TONIGHT BEFORE MAKING CHANGES. THE NIGHT
SHIFT CAN REEVALUATE WHETHER OR NOT TO CHANGE THE CURRENT WARNINGS
AND ADVISORIES.
&&
.PREV DISCUSSION... /ISSUED 719 PM CDT THU MAY 2 2013/
UPDATE...
IT CONTINUES TO SNOW ACROSS NW WISCONSIN EARLY THIS EVENING. IT
ALSO APPEARS TO BE SNOWING LIGHT OVER THE EASTERN ARROWHEAD OF
MINNESOTA...BUT LITTLE TO NO ADDITIONAL ACCUMULATION IS EXPECTED
THROUGH THE REMAINDER OF THE NIGHT. THEREFORE...I LET THE WINTER
WEATHER ADVISORY FOR SOUTHERN COOK COUNTY EXPIRE AS PLANNED. I LET
THE WINTER STORM WARNINGS AND ADVISORY FOR COUNTIES IN NW
WISCONSIN CONTINUE THROUGH TOMORROW MORNING DUE TO THE EXPECTED
ADDITIONAL SNOW AND POTENTIAL FREEZING RAIN. THE LATEST NAM12
SOUNDINGS AND HRRR MODEL RUNS SEEM TO INDICATE THE FREEZING RAIN
MIGHT NOT BEGIN TO MOVE INTO NW WISCONSIN UNTIL VERY LATE
TONIGHT...SO I MIGHT DELAY ITS TIMING IN THE FORECAST WITH A LATER
UPDATE LATER THIS EVENING.
PREV DISCUSSION... /ISSUED 620 PM CDT THU MAY 2 2013/
AVIATION.../00Z TAF ISSUANCE/
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A
WINTRY MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY
EARLY FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW
WISCONSIN WILL LIKELY CONTINUE THROUGH FRIDAY. UNFORTUNATELY...THE
OBSERVATION EQUIPMENT AT KHYR IS INOPERABLE...SO I AM UNABLE TO
KNOW WHAT IS EXACTLY HAPPENING AT KHYR. I PROVIDED A BEST GUESS
FORECAST FOR KHYR THROUGH FRIDAY...AND I WILL NOT BE PLANNING TO
MAKE ANY AMENDMENTS FOR THIS SITE.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY
BE -RA.
PREV DISCUSSION... /ISSUED 351 PM CDT THU MAY 2 2013/
SHORT TERM...THROUGH EARLY FRIDAY EVENING.
WHAT AN IMPRESSIVE EVENT SO FAR...WITH MAX SNOWFALL SO FAR OF 16
INCHES 8 MILES SOUTH OF HAYWARD AND IN ASHLAND. I THINK IT`S
LIKELY THERE WILL BE SOME HIGHER TOTALS THAT COME IN AS ADDITIONAL
REPORTS FILTER IN LATE THIS AFTERNOON OR EVENING.
OVERALL...SNOWFALL INTENSITY WAS DIMINISHING WITH MOST OBSERVATIONS
SHOWING VSBYS AT OR ABOVE THREE QUARTERS OF A MILE. A SPOTTER
REPORTED THE SNOW HAD ENDED FOR NOW IN OGEMA IN SOUTHERN PRICE
COUNTY. WARM AIR ADVECTION AND A TROUGH SHOULD CAUSE PRECIPITATION
TO EXPAND OVERNIGHT OVER NORTHWEST WISCONSIN...AND THE WARMER AIR
ALOFT MOVING IN SHOULD CAUSE A WINTRY MIX TO OCCUR BY LATE TONIGHT
OR FRIDAY MORNING OVER MOST AREAS OF OUR WISCONSIN CWA. HEADLINES
WERE A CHALLENGE OVERNIGHT...AND WE OPTED TO EXTEND THE WARNING
FOR ASHLAND/BAYFIELD/IRON/SAWYER AND PRICE COUNTIES...RATHER THAN
CHANGE IT OVER TO AN ADVISORY. WE DID CHANGE WASHBURN TO AN
ADVISORY...AS MUCH OF THAT COUNTY HAS NOT HAD MUCH ADDITIONAL
SNOWFALL. WE`LL RELAY ADDITIONAL SNOWFALL AND POSSIBLE LIGHT ICE
ACCUMULATIONS IN THE HWO/STATEMENTS/ZONES/GRAPHICAST. WE EXPECT
ANOTHER INCH OR TWO TONIGHT/FRIDAY MORNING...WITH THAT SAME AMOUNT
POSSIBLE THIS AFTERNOON INTO EARLY EVENING.
MODELS ARE IN DECENT AGREEMENT THROUGH THE PERIOD...AND FINALLY ARE IN
GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER TROUGH THAT WILL
CUT OFF A LOW IN THE CENTRAL PLAINS TONIGHT INTO FRIDAY. THE GFS
WAS MUCH CLOSER THAN THE ECMWF WITH THIS A COUPLE DAYS AGO.
WE DELAYED THE WESTWARD MENTION OF POPS ON FRIDAY AS THE MODELS
KEEP THE BULK OF THE PRECIP OVER NORTHWEST WISCONSIN. WE EXPECT A
TRANSITION TO MAINLY RAIN BY AFTERNOON AS WARMER TEMPS ALOFT
CONTINUE TO ADVECT WEST AND BOUNDARY LAYER TEMPS WARM ABOVE
FREEZING.
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY.
MAIN FOCUS IN EXTENDED IS THREAT FOR FZRA FRIDAY NIGHT AS ANOTHER
ROUND OF RAIN LIFTS NORTH OVER THE REGION. AT THIS TIME...THERE IS A
POTENTIAL FOR SOME LIGHT ICE ACCUM IS OVER THE WIS ZONES...AS WELL
AS IN THE MN ARROWHEAD WHERE SFC TEMPS LOOK TO FALL BELOW FREEZING
AS THE MID LEVELS QUICKLY WARM THROUGH THE NIGHT. AN ONSHORE FLOW
WITH WATER TEMPS IN THE MID 30S SHOULD KEEP AREAS NEAR LAKE SUPERIOR
WARM ENOUGH FOR ALL RA.
A COLD CORE LOW IN THE SOUTHERN STREAM...BECOMES CUT-OFF OVER THE SE
CONUS THROUGH THE WEEKEND. A H85 TROUGH AND REGION OF FGEN EXTENDING
NORTH FROM THE LOW...ACROSS THE NORTHLAND...WILL BE THE FOCUS FOR
ONGOING RAIN FRIDAY NIGHT THROUGH SATURDAY NIGHT. THE LATEST NAM/GFS
BOTH SHOW PWATS INCREASING FROM THE SOUTHEAST FRIDAY
NIGHT...REACHING AROUND AN INCH OVER THE SRN HALF OF THE FA BY SAT
AFTRN. MUCH OF THE NORTHLAND CAN EXPECT RAINFALL TOTALS ON THE ORDER
OF A HALF TO ONE INCH...WITH LOCALLY HIGHER AMOUNTS.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY INTO
FRIDAY WILL SLOW THE MELT...BUT TEMPS WILL START TO WARM THIS
WEEKEND INTO NEXT WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 28 42 32 39 / 10 20 80 60
INL 22 48 29 50 / 0 0 10 10
BRD 29 48 34 44 / 0 10 50 60
HYR 30 40 32 43 / 60 70 80 60
ASX 29 37 32 38 / 70 70 80 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 11 AM CDT FRIDAY FOR WIZ002>004-008-
009.
WINTER WEATHER ADVISORY UNTIL 11 AM CDT FRIDAY FOR WIZ007.
LS...SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO 1 AM CDT SATURDAY FOR
LSZ144>146.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-147-148.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS DULUTH MN
719 PM CDT THU MAY 2 2013
.UPDATE...
IT CONTINUES TO SNOW ACROSS NW WISCONSIN EARLY THIS EVENING. IT
ALSO APPEARS TO BE SNOWING LIGHT OVER THE EASTERN ARROWHEAD OF
MINNESOTA...BUT LITTLE TO NO ADDITIONAL ACCUMULATION IS EXPECTED
THROUGH THE REMAINDER OF THE NIGHT. THEREFORE...I LET THE WINTER
WEATHER ADVISORY FOR SOUTHERN COOK COUNTY EXPIRE AS PLANNED. I LET
THE WINTER STORM WARNINGS AND ADVISORY FOR COUNTIES IN NW
WISCONSIN CONTINUE THROUGH TOMORROW MORNING DUE TO THE EXPECTED
ADDITIONAL SNOW AND POTENTIAL FREEZING RAIN. THE LATEST NAM12
SOUNDINGS AND HRRR MODEL RUNS SEEM TO INDICATE THE FREEZING RAIN
MIGHT NOT BEGIN TO MOVE INTO NW WISCONSIN UNTIL VERY LATE
TONIGHT...SO I MIGHT DELAY ITS TIMING IN THE FORECAST WITH A LATER
UPDATE LATER THIS EVENING.
&&
.PREV DISCUSSION... /ISSUED 620 PM CDT THU MAY 2 2013/
AVIATION.../00Z TAF ISSUANCE/
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A
WINTRY MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY
EARLY FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW
WISCONSIN WILL LIKELY CONTINUE THROUGH FRIDAY. UNFORTUNATELY...THE
OBSERVATION EQUIPMENT AT KHYR IS INOPERABLE...SO I AM UNABLE TO
KNOW WHAT IS EXACTLY HAPPENING AT KHYR. I PROVIDED A BEST GUESS
FORECAST FOR KHYR THROUGH FRIDAY...AND I WILL NOT BE PLANNING TO
MAKE ANY AMENDMENTS FOR THIS SITE.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY
BE -RA.
PREV DISCUSSION... /ISSUED 351 PM CDT THU MAY 2 2013/
SHORT TERM...THROUGH EARLY FRIDAY EVENING.
WHAT AN IMPRESSIVE EVENT SO FAR...WITH MAX SNOWFALL SO FAR OF 16
INCHES 8 MILES SOUTH OF HAYWARD AND IN ASHLAND. I THINK IT`S
LIKELY THERE WILL BE SOME HIGHER TOTALS THAT COME IN AS ADDITIONAL
REPORTS FILTER IN LATE THIS AFTERNOON OR EVENING.
OVERALL...SNOWFALL INTENSITY WAS DIMINISHING WITH MOST OBSERVATIONS
SHOWING VSBYS AT OR ABOVE THREE QUARTERS OF A MILE. A SPOTTER
REPORTED THE SNOW HAD ENDED FOR NOW IN OGEMA IN SOUTHERN PRICE
COUNTY. WARM AIR ADVECTION AND A TROUGH SHOULD CAUSE PRECIPITATION
TO EXPAND OVERNIGHT OVER NORTHWEST WISCONSIN...AND THE WARMER AIR
ALOFT MOVING IN SHOULD CAUSE A WINTRY MIX TO OCCUR BY LATE TONIGHT
OR FRIDAY MORNING OVER MOST AREAS OF OUR WISCONSIN CWA. HEADLINES
WERE A CHALLENGE OVERNIGHT...AND WE OPTED TO EXTEND THE WARNING
FOR ASHLAND/BAYFIELD/IRON/SAWYER AND PRICE COUNTIES...RATHER THAN
CHANGE IT OVER TO AN ADVISORY. WE DID CHANGE WASHBURN TO AN
ADVISORY...AS MUCH OF THAT COUNTY HAS NOT HAD MUCH ADDITIONAL
SNOWFALL. WE`LL RELAY ADDITIONAL SNOWFALL AND POSSIBLE LIGHT ICE
ACCUMULATIONS IN THE HWO/STATEMENTS/ZONES/GRAPHICAST. WE EXPECT
ANOTHER INCH OR TWO TONIGHT/FRIDAY MORNING...WITH THAT SAME AMOUNT
POSSIBLE THIS AFTERNOON INTO EARLY EVENING.
MODELS ARE IN DECENT AGREEMENT THROUGH THE PERIOD...AND FINALLY ARE IN
GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER TROUGH THAT WILL
CUT OFF A LOW IN THE CENTRAL PLAINS TONIGHT INTO FRIDAY. THE GFS
WAS MUCH CLOSER THAN THE ECMWF WITH THIS A COUPLE DAYS AGO.
WE DELAYED THE WESTWARD MENTION OF POPS ON FRIDAY AS THE MODELS
KEEP THE BULK OF THE PRECIP OVER NORTHWEST WISCONSIN. WE EXPECT A
TRANSITION TO MAINLY RAIN BY AFTERNOON AS WARMER TEMPS ALOFT
CONTINUE TO ADVECT WEST AND BOUNDARY LAYER TEMPS WARM ABOVE
FREEZING.
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY.
MAIN FOCUS IN EXTENDED IS THREAT FOR FZRA FRIDAY NIGHT AS ANOTHER
ROUND OF RAIN LIFTS NORTH OVER THE REGION. AT THIS TIME...THERE IS A
POTENTIAL FOR SOME LIGHT ICE ACCUM IS OVER THE WIS ZONES...AS WELL
AS IN THE MN ARROWHEAD WHERE SFC TEMPS LOOK TO FALL BELOW FREEZING
AS THE MID LEVELS QUICKLY WARM THROUGH THE NIGHT. AN ONSHORE FLOW
WITH WATER TEMPS IN THE MID 30S SHOULD KEEP AREAS NEAR LAKE SUPERIOR
WARM ENOUGH FOR ALL RA.
A COLD CORE LOW IN THE SOUTHERN STREAM...BECOMES CUT-OFF OVER THE SE
CONUS THROUGH THE WEEKEND. A H85 TROUGH AND REGION OF FGEN EXTENDING
NORTH FROM THE LOW...ACROSS THE NORTHLAND...WILL BE THE FOCUS FOR
ONGOING RAIN FRIDAY NIGHT THROUGH SATURDAY NIGHT. THE LATEST NAM/GFS
BOTH SHOW PWATS INCREASING FROM THE SOUTHEAST FRIDAY
NIGHT...REACHING AROUND AN INCH OVER THE SRN HALF OF THE FA BY SAT
AFTRN. MUCH OF THE NORTHLAND CAN EXPECT RAINFALL TOTALS ON THE ORDER
OF A HALF TO ONE INCH...WITH LOCALLY HIGHER AMOUNTS.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY INTO
FRIDAY WILL SLOW THE MELT...BUT TEMPS WILL START TO WARM THIS
WEEKEND INTO NEXT WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 28 42 32 39 / 10 20 80 60
INL 20 48 29 50 / 0 0 10 10
BRD 29 48 34 44 / 0 10 50 60
HYR 31 40 32 43 / 70 70 80 60
ASX 29 37 32 38 / 70 70 80 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 11 AM CDT FRIDAY FOR WIZ002>004-008-
009.
WINTER WEATHER ADVISORY UNTIL 11 AM CDT FRIDAY FOR WIZ007.
LS...SMALL CRAFT ADVISORY FROM 4 AM FRIDAY TO 1 AM CDT SATURDAY FOR
LSZ144>146.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-147-148.
&&
$$
SHORT TERM...GROCHOCINSKI
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
149 PM CDT WED MAY 1 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM CDT WED MAY 1 2013
NOT THE TYPICAL MAY FORECAST. CDFNT HAS SETTLED OVER SE WI AND
STRETCHES SWWD INTO CENTRAL AND SRN IA...AND WILL REMAIN QUASI-
STNRY OVER THESE AREAS THRU THE NEXT 24 HRS. SIGNIFICANT CAA IS IN
PROGRESS AS EVIDENCED BY TEMPS IN THE LOW 30S IN NRN AND WRN MN
WHILE THE ERN AND SRN MN INTO WRN WI IS IN THE 40S AND 50S. A
POTENT UPR LEVEL TROF WILL STALL OUT OVER THE NRN PLAINS AND UPR
MISS RIVER VALLEY...DIGGING FURTHER S AND SLIGHTLY PIVOTING TO
ENHANCE LIFT AND ALSO ALLOW A PROLONGED STREAM OF SRN MOISTURE TO
ADVECT WELL N INTO THIS REGION...DEEPENING THE MOISTURE COLUMN.
PWATS SURGE TO WELL OVER AN INCH THRU TNGT. IN ADDITION...MOST
RAIN/SNOW LAYER THRESHOLDS BECOME MUCH SHORTER PER BUFKIT PROFILES
BY LATE AFTN...INDICATING THAT THE PRECIP FALLING WILL TAKE THE
FORM OF SNOW RATHER THAN RAIN...HIGHLY UNUSUAL FOR THE MONTH OF
MAY. IN FACT...LOCAL HOPWRF GUIDANCE SHOWS SEVERAL SWATHS OF 1-3
IN/HR SNOW BANDS INTO CENTRAL-ERN MN BY MIDDAY WHICH MAKES SENSE
GIVEN THAT SPC SREF AND RAP GUIDANCE INDICATES VERY STRONG H7
FGEN. THE MAIN CONCERN IS THAT DEWPOINTS ARE STILL IN THE LOWER
20S WHERE TEMPS HAVE DROPPED TO THE FREEZING MARK. SHOULD
WETBULBING EFFECTS OCCUR...DROPPING THE TEMP FASTER THAN
ADVERTISED AND KEEPING IT THERE...ACCUMULATIONS COULD OCCUR
QUICKER AND EARLIER THAN ADVERTISED DESPITE THE WARM ROAD SFC
TEMPS OF THE PAST SEVERAL DAYS. COULD SEE 1-3 INCHES OF SOLID
ACCUMULATION THIS AFTN ONCE THE RAIN CHANGES OVER TO SNOW AND
INTENSITY IS MOD-HVY. WILL STILL LOOK FOR TEMPS TO FALL THRU THE
DAY TDA AND TNGT AS THE UPR TROF CONTINUES TO DIG OVER THE DAKOTAS
AND SFC WINDS SHIFT TO NW-N. GOING INTO TNGT...AT LEAST ONE HVY
BAND OF SNOW IS EXPECTED TO DEVELOP FROM NRN IA INTO SRN AND SE
MN...WITH STRONG FGEN OVER THIS SAME AREA LASTING THROUGH
DAYBREAK ON THU. BUFKIT SOUNDINGS STILL SHOW SOLID SUBFREEZING
SOUNDINGS WITH MOD-HVY SNOW ALONG A MANKATO-MINNEAPOLIS-BARRON
LINE WHERE 6-9 INCHES OF ACCUMULATION IS CERTAINLY WITHIN REASON
IN THIS FORECAST. GOING FURTHER E AND W...ACCUMULATIONS DROP OFF
IN A RATHER TIGHT GRADIENT...SUCH THAT NWRN PORTIONS OF THE MPX
CWFA MAY NOT EVEN SEE 1 INCH. THAT SAID...WPC GUIDANCE STILL PINS
A 8-10 INCH SWATH OF SNOWFALL OVER S-CENTRAL MN INTO E-CENTRAL MN
AND W-CENTRAL WI...AND WITH QPF NEARING AN INCH...EVEN SNOWFALL
RATIOS IN THE 4 OR 5 TO 1 AREA PRODUCE A STORM TOTAL OF 4-7
INCHES THRU TNGT WITH SLIGHT ADDITIONS FOR THU. NORMALLY THE
WARMER GROUND WOULD BE ABLE TO MELT THE SNOW AS IT FALLS...AND THE
WET NATURE OF THE SNOW WOULD ALSO HINDER ACCUMULATIONS. HOWEVER...
THE STRONG FGEN WITH HIGH SNOWFALL RATES FOR SEEM TO COMBAT THAT
THINKING IN THIS CASE...LEANING MORE TWD AGREEMENT WITH THE WPC
OUTPUT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 441 AM CDT WED MAY 1 2013
MODEL AGREEMENT THIS PERIOD REMAINS HIGH THROUGH FRIDAY...BUT
QUICKLY DISAPPEARS FROM FRIDAY NIGHT ONWARDS WITH HOW EACH MODEL
HANDLES THE PROGRESSION OF WHAT WILL BE A CUT OFF LOW THAT SETS UP
NEAR KANSAS CITY BY SATURDAY MORNING. ABOUT THE ONLY THING THERE IS
AGREEMENT ON BEYOND FRIDAY IS THAT HEIGHTS WILL SLOWLY MODIFY FROM
THE WEEKEND INTO NEXT WEEK...WHICH WILL ALLOW HIGHS TO WORK BACK
CLOSER TO EARLY MAY NORMALS.
FOR THURSDAY...FGEN INDUCED BAND OF HEAVY PRECIPITATION WILL
SLOWLY MOVE INTO WRN WI THU MORNING...AND LOOKS TO SPEND MOST OF
THE DAY CONFINED TO AREAS EAST OF AN ALBERT LEA TO RUSH CITY LINE.
GIVEN EXPECTED PERSISTENT PRECIPITATION AND CLOUD COVER...NUDGED
HIGHS DOWN INTO THE MID 30S FOR THURSDAY ACROSS ERN AREAS...WHICH
IS ABOUT 30 DEGREES BELOW NORMAL. OF COURSE THE OTHER IMPACT OF
THE COOLER TEMPS FOR THURSDAY IS THIS MAY ALLOW SNOW TO BE THE
PREDOMINATE P-TYPE FROM WED NIGHT RIGHT THROUGH THE DAY ON
THURSDAY. THE ONLY THING THAT HAS REALLY CHANGED IS A WESTWARD
SHIFT IN THE WARM NOSE BETWEEN H8 AND H7. THE GFS IN PARTICULAR
BRINGS THIS OUT TO ABOUT AN EAU CLAIRE TO LADYSMITH LINE...WITH A
PRETTY SHARP GRADIENT IN POTENTIAL SNOW TOTALS RESULTING ACROSS
THE ERN CWA...WITH VERY LITTLE ACCUMS AT AUGUSTA...WHILE A
MENOMONIE WOULD HAVE THE POTENTIAL FOR AROUND 8 INCHES. GIVEN THE
COOLER TEMPERATURES FOR THURSDAY AND THE POTENTIAL FOR CONTINUED
SNOW ACCUMS THROUGH THE DAY...WE DECIDED TO CARRY WINTER HEADLINES
THROUGH 00Z /7 PM THU/. AS WITH THE SHORT TERM...SNOW TOTALS ARE
TRICKY HERE AS GIVEN THE RATHER HIGH QPF NUMBERS...EVEN
POTENTIALLY UNREALISTIC SNOW RATIOS OF 4-6:1 STILL YIELD SNOWFALL
AMOUNTS THAT ARE OFF INTO UNCHARTED TERRITORY FOR MAY SNOWFALLS IN
THIS AREA. CURRENT GRIDS HAVE ABOUT A 100 MILE WIDE SWATH OF 6-9
INCHES OF SNOW THAT IS CENTERED ALONG A BLUE EARTH /CITY/...TO
HASTINGS...TO CUMBERLAND...WI LINE.
THOUGH CERTAINLY THE WARM SOILS/PAVEMENT TEMPS FROM THE RECENT
WARM SPELL WILL HAVE THE POTENTIAL TO LIMIT ACCUMULATIONS...
EXPECTED SNOWFALL RATES FROM TONIGHT INTO AT LEAST THURSDAY
MORNING IN THE 1-2 INCH PLUS RANGE WILL BE MORE THAN ENOUGH TO
ACCUMULATE ON ANY SURFACE WHILE THOSE TYPES OF RATES ARE BEING
OBSERVED. THERE IS CERTAINLY POTENTIAL FOR SNOWFALL AMOUNTS TO GO
EITHER WAY /HIGHER OR LOWER/ WITH THIS SYSTEM...BUT IF THE CURRENT
FORECAST DOES PAN OUT...THIS STORM WILL CERTAINLY BE RE- WRITING
THE RECORD BOOKS FOR MAY SNOWFALL ACROSS SOUTHERN MN AND WRN WI.
FOR THURSDAY NIGHT INTO FRIDAY...THE FOCUS FOR THE HEAVY
PRECIPITATION SHIFTS EAST FROM ERN IA INTO CENTRAL WI AS LLJ
SLOWLY SHIFTS EAST. AS RESULT...HAVE CUT BACK ON POPS IN THIS
PERIOD... ESPECIALLY ACROSS MN...WITH MUCH OF THE AREA LIKELY
SEEING A BIT OF A REPRIEVE FROM THE PRECIPITATION. IN
ADDITION...WRN MN WILL LIKELY SEE SOME FILTERED SUNSHINE...WHICH
WILL ALLOW WRN AREAS TO WARM BACK TOWARD THE 50S.
FOR FRIDAY NIGHT...MODEL DISAGREEMENTS START TO INCREASE
DRAMATICALLY WITH HANDLING OF A SURGE OF WAA ADVECTIVE PRECIP THAT
WILL BE COMING IN FROM THE SE AS A STRONG VORT MAX ROTATES
AROUND THE MAIN UPPER LOW OVER NRN MO /OFF THE NAM ANYWAYS/. THE
NAM IS THE MIDDLE MEMBER WITH THIS FEATURE...BRINGING ANOTHER
SHIELD OF HEAVY PRECIPITATION ACROSS THE MPX CWA FRIDAY NIGHT INTO
SATURDAY MORNING. THE GFS HAS A SIMILAR FEATURE...BUT KEEPS THE
BRUNT OF THE PRECIPITATION DOWN ACROSS IA. THE ECMWF HAS A
COMPLETELY DIFFERENT IDEA WITH HOW THIS UPPER LOW WILL EVOLVE.
WHERE THE GFS ON SAT HAS THE UPPER LOW OVER NRN ARK...THE NAM OVER
NRN MO...THE 01.00 ECMWF HAS THE SAME...MUCH SHALLOWER LOW UP NEAR
THE MN/DAKOTAS BORDER! GIVEN THE DISAGREEMENTS...HELD POPS TO NO
HIGHER THAN LIKELY ON SATURDAY AS IT COULD RANGE FROM ANYWHERE
BETWEEN A WASHOUT TO JUST COOL AND CLOUDY. AT THE VERY LEAST...AT
LEAST THIS POTENTIAL WAVE OF PRECIPITATION LOOKS TO BE WARM ENOUGH
TO KEEP EVERYTHING LIQUID.
GOING INTO NEXT WORK WEEK...BOTH THE GFS AND THE ECMWF SHOW
ANOTHER OMEGA BLOCK DEVELOPING...ONLY THIS TIME ACROSS THE WRN
US. THE ECMWF IS THE FARTHEST WEST WITH THIS FEATURE...WHICH
ALLOWS IT TO SEND ANOTHER STRONG SHORTWAVE AND COLD FRONT THROUGH
THE MPX AREA MONDAY NIGHT INTO TUESDAY. THE GFS HAS THE BLOCK
FARTHER EAST AND WOULD KEEP THE REGION DRY. AT THIS POINT...KEPT
THE MAINLY CHANCE POPS THAT WERE IN PLACE DURING THIS TIME FRAME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 119 PM CDT WED MAY 1 2013
PESKY BAND OF RAIN AND SNOW STILL EXTENDS FROM JUST WEST OF RNH TO
MSP AND SOUTHEAST OF RWF. THINK A DIMINISHING TREND WILL CONTINUE
DURING THE AFTERNOON BEFORE THE NEXT ROUND BEGINS TO PUSH IN FROM
THE SOUTHWEST. THE NEXT ROUND THIS EVENING WILL BE MAINLY
SNOW...EXCEPT TOWARD EAU WHERE IT WILL REMAIN A MIX INTO THE
OVERNIGHT. COULD SEE BANDS OF HEAVY SNOW FROM MKT TO MSP AND
NORTHEAST AROUND MIDNIGHT...BEFORE THE PRECIP BEGINS TO INCH
EASTWARD INTO THURSDAY MORNING. RWF/STC/AXN SHOULD MISS OUT ON
PRECIPITATION FOR THE REST OF THE PERIOD WITH VFR CONDITIONS
EXPECTED.
KMSP...MAIN FORECAST CONCERN IS HOW MUCH SNOW STICKS TO PAVEMENT
TONIGHT. LOOKING AT A PERIOD OF HEAVY SNOW POTENTIALLY LATE THIS
EVENING AND OVERNIGHT WHILE TEMPERATURES HOVER NEAR FREEZING. THIS
COULD BE SUFFICIENT TO GET ACCUMULATING SNOW.
/OUTLOOK FOR KMSP/
FRI...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA/-SN. NE WINDS 10-15
KT.
SAT...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA. ENE WINDS 5 KT.
SUN...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA. LGT/VRBL WINDS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING UNTIL 7 PM CDT THURSDAY FOR MNZ053-060>063-
067>070-074>078-082>085-091>093.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT THURSDAY FOR MNZ044-045-
051-052-058-059-065-066-073.
WI...WINTER STORM WARNING UNTIL 7 PM CDT THURSDAY FOR WIZ014>016-
023>025.
WINTER WEATHER ADVISORY UNTIL 7 PM CDT THURSDAY FOR WIZ026>028.
&&
$$
SHORT TERM...JPC
LONG TERM...MPG
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1227 PM CDT WED MAY 1 2013
.AVIATION.../18Z TAF ISSUANCE/
A STORM SYSTEM WILL BRING WINTRY WEATHER LATER TODAY AND INTO
TOMORROW MORNING FOR NW WISCONSIN AND SOME PARTS OF FAR EASTERN
MINNESOTA...INCLUDING KDLH. RAIN ACROSS NW WISCONSIN THIS
AFTERNOON WILL TRANSITION TO SNOW BY THIS EVENING AND THEN
CONTINUE THROUGH TOMORROW MORNING. MOST OF THE PRECIPITATION WILL
BE CONFINED TO NW WISCONSIN...BUT SOME LIGHT SNOW MAY MOVE INTO
THE KDLH AREA. EXPECT A PROLONGED PERIOD OF LIFR/IFR CONDITIONS AT
KHYR DUE TO THE LOW CIGS AND REDUCED VSBY FROM THE SNOW. I THINK
KDLH WILL NOT BE QUITE AS AFFECTED...BUT THERE SHOULD BE PERIODS
OF MVFR CIGS AND/OR VSBYS.
THE REST OF NE MINNESOTA SHOULD BE UNAFFECTED BY THE STORM SYSTEM.
THERE WILL BE PERIODS OF MVFR CIGS AT KHIB AND KDLH DUE TO
LINGERING LOW CIGS IN THE NW WINDS. I AM NOT CONFIDENT ENOUGH THAT
THESE CLOUDS WILL CONTINUE BEYOND THIS AFTERNOON TO MAINTAIN THE
MVFR THROUGH THIS EVENING...BUT THE LOW CIGS COULD CONTINUE
OVERNIGHT.
THE WNW WINDS AROUND 10 KNOTS WILL BECOME NNW TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 1055 AM CDT WED MAY 1 2013/
UPDATE...
A NARROW BAND OF RAIN AND SNOW EXTENDED NORTHEAST ACROSS SOUTHERN
PINE COUNTY ACROSS BURNETT...WASHBURN...DOUGLAS AND BAYFIELD
COUNTIES. KRZN HAS RECENTLY WENT TO SNOW...AND A SPOTTER IN
HERBSTER WAS ALSO REPORTING SNOW. THE RAP WAS SHOWING LOWER
WETBULB ZERO VALUES THIS MORNING...BUT HAD THEM INCREASING AGAIN
THIS AFTERNOON. WE THINK THE RAP MAY BE OVERDOING THE INCREASE
THIS AFTERNOON SOME AS THEY RAISE SURFACE TEMPS BACK INTO THE
FORTIES WHICH LOOKS UNLIKELY. SNOWFALL TODAY SHOULD BE LIMITED TO
LESS THAN AN INCH.
THE LATEST NAM STILL SHOWS IMPRESSIVE FGEN TONIGHT...AND WE EXPECT
HEAVY SNOW TO DEVELOP. THE CURRENT HEADLINES BASED ON THE NAM
STILL LOOK GOOD ACROSS WISCONSIN...BUT IT`S LOOKING MORE LIKELY
WE`LL NEED TO UPGRADE IRON COUNTY TO A WARNING. PRICE IS STILL
QUESTIONABLE...BUT THE NORTHERN HALF OF THE COUNTY SHOULD RECEIVE
SOME HEAVY SNOW SO WE MAY HAVE TO UPGRADE THEM AS WELL. WE`LL LOOK
OVER THE LATEST MODELS AND WAIT UNTIL THE AFTERNOON BEFORE MAKING
ANY CHANGES.
WE ALSO MAY HAVE TO INCREASE SNOW TOTALS ACROSS PORTIONS OF
NORTHWEST WISCONSIN GIVEN THE LATEST NAM. WE`LL WAIT FOR THE
GFS/ECMWF BEFORE FINALIZING SNOW TOTALS THIS AFTERNOON. WE
WOULDN`T BE SURPRISED IF SOME THUNDERSNOW DEVELOPS OVERNIGHT...AS
CROSS SECTIONS SHOW IMPRESSIVE FGEN WITH SOME NEGATIVE EPV AND
EVEN LOW CAPE FEEDING INTO NORTHWEST WISCONSIN. CONVECTIVE
SNOWFALL CAN PRODUCE HEAVY SNOW RATES...WITH 2 TO 3 INCHES PER
HOUR POSSIBLE.
PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 1 2013/
SHORT TERM...TODAY THROUGH THURSDAY.
THINGS ARE COMING TOGETHER FOR A FAIRLY MAJOR EARLY MAY SNOW STORM
ACROSS THE NORTHLAND. THE MODELS CONTINUE TO INDICATE THE
POTENTIAL FOR VERY HEAVY SNOW ACCUMULATION TONIGHT AND THURSDAY
ACROSS NORTHWESTERN WISCONSIN. THE MODELS DIFFER TO SOME EXTENT ON
THE SNOW POTENTIAL ON THE MINNESOTA SIDE...AND ALSO IN THE HURLEY
AND PARK FALLS AREAS. HAVE UPGRADED THE WATCH FOR MOST OF
NORTHWESTERN WISCONSIN TO A WARNING...BUT WILL KEEP IRON AND PRICE
COUNTIES IN A WATCH FOR NOW. ON THE MINNESOTA SIDE...HAVE ISSUED A
WINTER WEATHER ADVISORY FOR SNOW FROM PINE COUNTY...TOWARD DULUTH
AND INTO THE ARROWHEAD.
THE MAJORITY OF THE MODEL SOLUTIONS PAINT ANYWHERE FROM 6 TO 12
INCHES OF TOTAL SNOW ACCUMULATION ACROSS MUCH OF NORTHWESTERN
WISCONSIN. THE SREF PLUMES SHOW A WIDE SPREAD OF POSSIBLE TOTAL
SNOWFALL...WITH AMOUNTS RANGING FROM LESS THAN AN INCH TO AS MUCH
AS 19 INCHES. THE MAJORITY OF THE VALUES LIE SOMEWHERE NEAR THE
MEAN...WHICH IS AROUND 11 INCHES AT KHYR. THE MEAN AT SIREN WI IS
CLOSE TO 8 INCHES...WITH A LITTLE OVER 10 INCHES AT ASHLAND.
FURTHER WEST...THERE IS A LOT MORE QUESTION ACROSS THE MN SIDE.
THE MEAN FROM THE PLUMES FOR DULUTH IS BETWEEN 3 AND 4 INCHES BUT
WITH A HUGE MODEL SPREAD. WE ARE FAIRLY CONFIDENT THAT A BAND OF
VERY HEAVY SNOW WILL SET UP ACROSS MUCH OF NW WI...BUT AMOUNTS
FURTHER WEST ARE STILL TRICKY DUE TO THE SHARP GRADIENT IN
SNOWFALL EXPECTED. FOR EXAMPLE...THE NAM AND THE GFS BRING VERY
LITTLE SNOW ACCUMULATION TO DULUTH...WHILE THE ECMWF BRINGS A GOOD
4 TO 6 INCHES.
FOR TODAY...WILL START WITH LIGHT RAIN ACROSS THE REGION...AS IT
SPREADS QUICKLY IN FROM THE SOUTHWEST. TEMPS WILL START OUT IN THE
30S NORTHWEST AND 50S SOUTHEAST. TEMPS WILL BEGIN TO FALL DURING
THE DAY...RESULTING IN A MIXING WITH SNOW. THE PRECIPITATION
SHOULD LARGELY BECOME ALL SNOW TONIGHT...WITH SNOWFALL RATES OF
MORE THAN AN INCH AN HOUR AT TIMES...ESPECIALLY IN THE WARNING
AREA.
THE SNOW WILL THEN BEGIN TO MIX WITH RAIN AS IT DIMINISHES BY
THURSDAY AFTERNOON. IN ALL WE THINK 6 TO 12 IN NW WI...AND 2 TO 4
OR 3 TO 6 IN ADJACENT AREAS OF NE MN.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
QUITE A BIT OF UNCERTAINTY THROUGHOUT THE LONG TERM PERIODS..
BEGINNING WITH HANDLING OF UPPER LOW THAT WILL DEVELOP OVER THE
CENTRAL U.S. OVER THE NEXT 36 HOURS. THERE IS STILL FAIRLY WIDE
RANGING DIVERGENCE IN THE MODEL GUIDANCE..WITH SEVERAL RUNS TAKING
THE LOW MORE EAST INTO THE OHIO VALLEY/LOWER GRT LAKES..WITH THE
ECMWF STILL BEING THE LONE MODEL OUT IN LIFTING THE LOW NWD ACROSS
MN FRIDAY-SATURDAY. IF THE ECM SOLUTION COMES TO BEAR..WE WILL
LIKELY HAVE A LONGER DURATION RAIN/SNOW EVENT OVER MUCH OF THE CWA
TO DEAL WITH EVEN AFTER THE HEAVY SNOWS OVER NW WISCONSIN IN THE
IMMEDIATE SHORT TERM.
SIMILAR STORY FOR HANDLING OF THE FLOW PATTERN AND FORCING FOR THE
SUNDAY-TUESDAY TIME FRAME..WITH EVEN MORE SPREAD IN THE VARIOUS
DETERMINISTIC AND ENSEMBLE SOLUTIONS. SOME HAVE A VERY BLOCKED/CUT
OFF PATTERN, WHILE OTHERS TRANSITION TO A MORE WNW PROGRESSIVE NRN
STREAM PATTERN BY TUESDAY.
NEEDLESS TO SAY..CONFIDENCE IN ANY DETAILS WHATSOEVER IS VERY LOW
RIGHT NOW FOR THE ENTIRE DAY 2-7 TIME PERIOD. GIVEN THIS..WE HAVE
OPTED TO KEEP A MENTION OF AT LEAST SOME CHANCES FOR PRECIP IN MOST
PERIODS..ALONG WITH TEMPS AT OR SLIGHTLY BELOW SEASONAL NORMS.
HYDROLOGY...
RIVERS LEVELS CONTINUE TO RISE..ALTHOUGH AT A SLOWER RATE THAN THE
PAST FEW DAYS ACROSS THE SOUTHERN PARTS OF THE CWA AS MOST SNOW HAS
MELTED AND IN MOVING WITHIN THE DRAINAGE SYSTEM. FLOOD WARNINGS ARE
IN EFFECT ALONG THE MISSISSIPPI RIVER AT AITKIN AND FORT RIPLEY AND
ALONG THE ST. LOUIS RIVER AT SCANLON FOR MINOR FLOODING. THERE ARE
ALSO AREAL FLOOD ADVISORIES ACROSS PARTS OF THE NORTHLAND DUE TO
SOME REPORTS OF FLOODING...INCLUDING ALONG AND OVER SOME ROADWAYS.
OF PARTICULAR CONCERN THE NEXT 48-60 HOURS IS VERY RAPID MELT/RUNOFF
AND AREAL/RIVER FLOODING ACROSS THE GOGEBIC RANGE AREA OF NORTHWEST
WISCONSIN. THE BAD RIVER CONTINUES TO RISE AS WELL...AND WE MAY BE
UPGRADING TO WARNING THERE AS WELL BUT ARE WAITING FOR SOME MORE
INFORMATION BEFORE DOING SO.
PRECIPITATION WILL OVERSPREAD NW WISCONSIN AND FAR EASTERN MINNESOTA
TODAY...AND IT WILL LIKELY CONTINUE THROUGH AT LEAST THURSDAY..
INITIALLY IN THE FORM OF RAIN..BUT TRANSITIONING TO SNOW LATE THIS
AFTERNOON AND TONIGHT. MUCH OF NORTHWEST WISCONSIN WILL LIKELY GET
AT LEAST A HALF INCH OF QPF THROUGH THURSDAY...WITH SOME
INDICATIONS OF OVER AN INCH. ALTHOUGH HEAVY WET SNOW IS EXPECTED
TONIGHT INTO THURSDAY...THIS PRECIPITATION WILL EVENTUALLY IMPACT
THE RIVER AND STREAMS. THE PRECIPITATION IS NOT EXPECTED TO HAVE
LARGE IMPACTS IMMEDIATELY TO FLOODING CONCERNS...BUT IT WILL
LIKELY RESULT IN ADDITIONAL RISES ALONG SOME STREAMS AND RIVERS
LATER THIS WEEK INTO THE WEEKEND.
&&
.POINT TEMPS/POPS...
DLH 31 43 32 39 / 70 70 20 40
INL 27 43 28 48 / 10 10 10 20
BRD 28 46 32 48 / 10 10 10 30
HYR 31 37 30 39 / 100 100 50 60
ASX 30 35 30 36 / 100 100 50 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT
THURSDAY FOR MNZ012-020-021-037-038.
WI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM CDT THURSDAY
FOR WIZ001>003-006>008.
WINTER STORM WATCH FROM 7 PM CDT THIS EVENING THROUGH THURSDAY
EVENING FOR WIZ004-009.
LS...NONE.
&&
$$
SHORT TERM...MELDE
AVIATION...GROCHOCINSKI
AREA FORECAST DISCUSSION
NWS DULUTH MN
1055 AM CDT WED MAY 1 2013
.UPDATE...
A NARROW BAND OF RAIN AND SNOW EXTENDED NORTHEAST ACROSS SOUTHERN
PINE COUNTY ACROSS BURNETT...WASHBURN...DOUGLAS AND BAYFIELD
COUNTIES. KRZN HAS RECENTLY WENT TO SNOW...AND A SPOTTER IN
HERBSTER WAS ALSO REPORTING SNOW. THE RAP WAS SHOWING LOWER
WETBULB ZERO VALUES THIS MORNING...BUT HAD THEM INCREASING AGAIN
THIS AFTERNOON. WE THINK THE RAP MAY BE OVERDOING THE INCREASE
THIS AFTERNOON SOME AS THEY RAISE SURFACE TEMPS BACK INTO THE
FORTIES WHICH LOOKS UNLIKELY. SNOWFALL TODAY SHOULD BE LIMITED TO
LESS THAN AN INCH.
THE LATEST NAM STILL SHOWS IMPRESSIVE FGEN TONIGHT...AND WE EXPECT
HEAVY SNOW TO DEVELOP. THE CURRENT HEADLINES BASED ON THE NAM
STILL LOOK GOOD ACROSS WISCONSIN...BUT IT`S LOOKING MORE LIKELY
WE`LL NEED TO UPGRADE IRON COUNTY TO A WARNING. PRICE IS STILL
QUESTIONABLE...BUT THE NORTHERN HALF OF THE COUNTY SHOULD RECEIVE
SOME HEAVY SNOW SO WE MAY HAVE TO UPGRADE THEM AS WELL. WE`LL LOOK
OVER THE LATEST MODELS AND WAIT UNTIL THE AFTERNOON BEFORE MAKING
ANY CHANGES.
WE ALSO MAY HAVE TO INCREASE SNOW TOTALS ACROSS PORTIONS OF
NORTHWEST WISCONSIN GIVEN THE LATEST NAM. WE`LL WAIT FOR THE
GFS/ECMWF BEFORE FINALIZING SNOW TOTALS THIS AFTERNOON. WE
WOULDN`T BE SURPRISED IF SOME THUNDERSNOW DEVELOPS OVERNIGHT...AS
CROSS SECTIONS SHOW IMPRESSIVE FGEN WITH SOME NEGATIVE EPV AND
EVEN LOW CAPE FEEDING INTO NORTHWEST WISCONSIN. CONVECTIVE
SNOWFALL CAN PRODUCE HEAVY SNOW RATES...WITH 2 TO 3 INCHES PER
HOUR POSSIBLE.
&&
.PREV DISCUSSION... /ISSUED 657 AM CDT WED MAY 1 2013/
AVIATION...12Z TAF ISSUANCE...
FRONT HAS STALLED FROM IOWA INTO CENTRAL WISCONSIN THIS
MORNING..WITH FOCUS FOR PRECIPITATION REMAINING LOCKED IN THE
CORRIDOR JUST ON THE COOL SIDE OF THE FRONT ACROSS NW
WISCONSIN..INCLUDING KHYR TAF SITE THROUGH TONIGHT. RAIN IS
ALREADY AFFECTING KHYR WITH VFR CEILING AS OF 11Z THIS MORNING.
HOWEVER..CEILINGS/VISIBILITIES ARE EXPECTED TO GRADUALLY LOWER
THROUGH THE DAY..WITH RAIN MIXING WITH AND EVENTUALLY CHANGING TO
SNOW THIS EVENING AND OVERNIGHT WITH IFR CIGS/VSBYS DEVELOPING.
THERE IS EXPECTED TO BE A VERY SHARP GRADIENT/CUT OFF IN PRECIP ON
THE NORTHWEST SIDE OF THIS SYSTEM..AND THUS KDLH/KBRD/KINL/KHIB
HAVE NO PRECIP MENTIONED THRU THE PERIOD WITH VFR CEILINGS AND
WINDS GRADUALLY VEERING FROM WNW TO N OR NNE BY TONIGHT.
PREV DISCUSSION... /ISSUED 430 AM CDT WED MAY 1 2013/
SHORT TERM...TODAY THROUGH THURSDAY.
THINGS ARE COMING TOGETHER FOR A FAIRLY MAJOR EARLY MAY SNOW STORM
ACROSS THE NORTHLAND. THE MODELS CONTINUE TO INDICATE THE
POTENTIAL FOR VERY HEAVY SNOW ACCUMULATION TONIGHT AND THURSDAY
ACROSS NORTHWESTERN WISCONSIN. THE MODELS DIFFER TO SOME EXTENT ON
THE SNOW POTENTIAL ON THE MINNESOTA SIDE...AND ALSO IN THE HURLEY
AND PARK FALLS AREAS. HAVE UPGRADED THE WATCH FOR MOST OF
NORTHWESTERN WISCONSIN TO A WARNING...BUT WILL KEEP IRON AND PRICE
COUNTIES IN A WATCH FOR NOW. ON THE MINNESOTA SIDE...HAVE ISSUED A
WINTER WEATHER ADVISORY FOR SNOW FROM PINE COUNTY...TOWARD DULUTH
AND INTO THE ARROWHEAD.
THE MAJORITY OF THE MODEL SOLUTIONS PAINT ANYWHERE FROM 6 TO 12
INCHES OF TOTAL SNOW ACCUMULATION ACROSS MUCH OF NORTHWESTERN
WISCONSIN. THE SREF PLUMES SHOW A WIDE SPREAD OF POSSIBLE TOTAL
SNOWFALL...WITH AMOUNTS RANGING FROM LESS THAN AN INCH TO AS MUCH
AS 19 INCHES. THE MAJORITY OF THE VALUES LIE SOMEWHERE NEAR THE
MEAN...WHICH IS AROUND 11 INCHES AT KHYR. THE MEAN AT SIREN WI IS
CLOSE TO 8 INCHES...WITH A LITTLE OVER 10 INCHES AT ASHLAND.
FURTHER WEST...THERE IS A LOT MORE QUESTION ACROSS THE MN SIDE.
THE MEAN FROM THE PLUMES FOR DULUTH IS BETWEEN 3 AND 4 INCHES BUT
WITH A HUGE MODEL SPREAD. WE ARE FAIRLY CONFIDENT THAT A BAND OF
VERY HEAVY SNOW WILL SET UP ACROSS MUCH OF NW WI...BUT AMOUNTS
FURTHER WEST ARE STILL TRICKY DUE TO THE SHARP GRADIENT IN
SNOWFALL EXPECTED. FOR EXAMPLE...THE NAM AND THE GFS BRING VERY
LITTLE SNOW ACCUMULATION TO DULUTH...WHILE THE ECMWF BRINGS A GOOD
4 TO 6 INCHES.
FOR TODAY...WILL START WITH LIGHT RAIN ACROSS THE REGION...AS IT
SPREADS QUICKLY IN FROM THE SOUTHWEST. TEMPS WILL START OUT IN THE
30S NORTHWEST AND 50S SOUTHEAST. TEMPS WILL BEGIN TO FALL DURING
THE DAY...RESULTING IN A MIXING WITH SNOW. THE PRECIPITATION
SHOULD LARGELY BECOME ALL SNOW TONIGHT...WITH SNOWFALL RATES OF
MORE THAN AN INCH AN HOUR AT TIMES...ESPECIALLY IN THE WARNING
AREA.
THE SNOW WILL THEN BEGIN TO MIX WITH RAIN AS IT DIMINISHES BY
THURSDAY AFTERNOON. IN ALL WE THINK 6 TO 12 IN NW WI...AND 2 TO 4
OR 3 TO 6 IN ADJACENT AREAS OF NE MN.
LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...
QUITE A BIT OF UNCERTAINTY THROUGHOUT THE LONG TERM PERIODS..
BEGINNING WITH HANDLING OF UPPER LOW THAT WILL DEVELOP OVER THE
CENTRAL U.S. OVER THE NEXT 36 HOURS. THERE IS STILL FAIRLY WIDE
RANGING DIVERGENCE IN THE MODEL GUIDANCE..WITH SEVERAL RUNS TAKING
THE LOW MORE EAST INTO THE OHIO VALLEY/LOWER GRT LAKES..WITH THE
ECMWF STILL BEING THE LONE MODEL OUT IN LIFTING THE LOW NWD ACROSS
MN FRIDAY-SATURDAY. IF THE ECM SOLUTION COMES TO BEAR..WE WILL
LIKELY HAVE A LONGER DURATION RAIN/SNOW EVENT OVER MUCH OF THE CWA
TO DEAL WITH EVEN AFTER THE HEAVY SNOWS OVER NW WISCONSIN IN THE
IMMEDIATE SHORT TERM.
SIMILAR STORY FOR HANDLING OF THE FLOW PATTERN AND FORCING FOR THE
SUNDAY-TUESDAY TIME FRAME..WITH EVEN MORE SPREAD IN THE VARIOUS
DETERMINISTIC AND ENSEMBLE SOLUTIONS. SOME HAVE A VERY BLOCKED/CUT
OFF PATTERN, WHILE OTHERS TRANSITION TO A MORE WNW PROGRESSIVE NRN
STREAM PATTERN BY TUESDAY.
NEEDLESS TO SAY..CONFIDENCE IN ANY DETAILS WHATSOEVER IS VERY LOW
RIGHT NOW FOR THE ENTIRE DAY 2-7 TIME PERIOD. GIVEN THIS..WE HAVE
OPTED TO KEEP A MENTION OF AT LEAST SOME CHANCES FOR PRECIP IN MOST
PERIODS..ALONG WITH TEMPS AT OR SLIGHTLY BELOW SEASONAL NORMS.
HYDROLOGY...
RIVERS LEVELS CONTINUE TO RISE..ALTHOUGH AT A SLOWER RATE THAN THE
PAST FEW DAYS ACROSS THE SOUTHERN PARTS OF THE CWA AS MOST SNOW HAS
MELTED AND IN MOVING WITHIN THE DRAINAGE SYSTEM. FLOOD WARNINGS ARE
IN EFFECT ALONG THE MISSISSIPPI RIVER AT AITKIN AND FORT RIPLEY AND
ALONG THE ST. LOUIS RIVER AT SCANLON FOR MINOR FLOODING. THERE ARE
ALSO AREAL FLOOD ADVISORIES ACROSS PARTS OF THE NORTHLAND DUE TO
SOME REPORTS OF FLOODING...INCLUDING ALONG AND OVER SOME ROADWAYS.
OF PARTICULAR CONCERN THE NEXT 48-60 HOURS IS VERY RAPID MELT/RUNOFF
AND AREAL/RIVER FLOODING ACROSS THE GOGEBIC RANGE AREA OF NORTHWEST
WISCONSIN. THE BAD RIVER CONTINUES TO RISE AS WELL...AND WE MAY BE
UPGRADING TO WARNING THERE AS WELL BUT ARE WAITING FOR SOME MORE
INFORMATION BEFORE DOING SO.
PRECIPITATION WILL OVERSPREAD NW WISCONSIN AND FAR EASTERN MINNESOTA
TODAY...AND IT WILL LIKELY CONTINUE THROUGH AT LEAST THURSDAY..
INITIALLY IN THE FORM OF RAIN..BUT TRANSITIONING TO SNOW LATE THIS
AFTERNOON AND TONIGHT. MUCH OF NORTHWEST WISCONSIN WILL LIKELY GET
AT LEAST A HALF INCH OF QPF THROUGH THURSDAY...WITH SOME
INDICATIONS OF OVER AN INCH. ALTHOUGH HEAVY WET SNOW IS EXPECTED
TONIGHT INTO THURSDAY...THIS PRECIPITATION WILL EVENTUALLY IMPACT
THE RIVER AND STREAMS. THE PRECIPITATION IS NOT EXPECTED TO HAVE
LARGE IMPACTS IMMEDIATELY TO FLOODING CONCERNS...BUT IT WILL
LIKELY RESULT IN ADDITIONAL RISES ALONG SOME STREAMS AND RIVERS
LATER THIS WEEK INTO THE WEEKEND.
&&
.POINT TEMPS/POPS...
DLH 45 31 43 32 / 50 70 70 20
INL 40 27 43 28 / 10 10 10 10
BRD 44 28 46 32 / 20 10 10 10
HYR 44 31 37 30 / 90 100 90 50
ASX 46 30 35 30 / 90 100 100 50
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 PM CDT
THURSDAY FOR MNZ012-020-021-037-038.
WI...WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM CDT THURSDAY
FOR WIZ001>003-006>008.
WINTER STORM WATCH FROM 7 PM CDT THIS EVENING THROUGH THURSDAY
EVENING FOR WIZ004-009.
LS...NONE.
&&
$$
SHORT TERM...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
712 AM CDT WED MAY 1 2013
.UPDATE...
ISSUED AT 643 AM CDT WED MAY 1 2013
UPDATED TO INCLUDE 12Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM CDT WED MAY 1 2013
NOT THE TYPICAL MAY FORECAST. CDFNT HAS SETTLED OVER SE WI AND
STRETCHES SWWD INTO CENTRAL AND SRN IA...AND WILL REMAIN QUASI-
STNRY OVER THESE AREAS THRU THE NEXT 24 HRS. SIGNIFICANT CAA IS IN
PROGRESS AS EVIDENCED BY TEMPS IN THE LOW 30S IN NRN AND WRN MN
WHILE THE ERN AND SRN MN INTO WRN WI IS IN THE 40S AND 50S. A
POTENT UPR LEVEL TROF WILL STALL OUT OVER THE NRN PLAINS AND UPR
MISS RIVER VALLEY...DIGGING FURTHER S AND SLIGHTLY PIVOTING TO
ENHANCE LIFT AND ALSO ALLOW A PROLONGED STREAM OF SRN MOISTURE TO
ADVECT WELL N INTO THIS REGION...DEEPENING THE MOISTURE COLUMN.
PWATS SURGE TO WELL OVER AN INCH THRU TNGT. IN ADDITION...MOST
RAIN/SNOW LAYER THRESHOLDS BECOME MUCH SHORTER PER BUFKIT PROFILES
BY LATE AFTN...INDICATING THAT THE PRECIP FALLING WILL TAKE THE
FORM OF SNOW RATHER THAN RAIN...HIGHLY UNUSUAL FOR THE MONTH OF
MAY. IN FACT...LOCAL HOPWRF GUIDANCE SHOWS SEVERAL SWATHS OF 1-3
IN/HR SNOW BANDS INTO CENTRAL-ERN MN BY MIDDAY WHICH MAKES SENSE
GIVEN THAT SPC SREF AND RAP GUIDANCE INDICATES VERY STRONG H7
FGEN. THE MAIN CONCERN IS THAT DEWPOINTS ARE STILL IN THE LOWER
20S WHERE TEMPS HAVE DROPPED TO THE FREEZING MARK. SHOULD
WETBULBING EFFECTS OCCUR...DROPPING THE TEMP FASTER THAN
ADVERTISED AND KEEPING IT THERE...ACCUMULATIONS COULD OCCUR
QUICKER AND EARLIER THAN ADVERTISED DESPITE THE WARM ROAD SFC
TEMPS OF THE PAST SEVERAL DAYS. COULD SEE 1-3 INCHES OF SOLID
ACCUMULATION THIS AFTN ONCE THE RAIN CHANGES OVER TO SNOW AND
INTENSITY IS MOD-HVY. WILL STILL LOOK FOR TEMPS TO FALL THRU THE
DAY TDA AND TNGT AS THE UPR TROF CONTINUES TO DIG OVER THE DAKOTAS
AND SFC WINDS SHIFT TO NW-N. GOING INTO TNGT...AT LEAST ONE HVY
BAND OF SNOW IS EXPECTED TO DEVELOP FROM NRN IA INTO SRN AND SE
MN...WITH STRONG FGEN OVER THIS SAME AREA LASTING THROUGH
DAYBREAK ON THU. BUFKIT SOUNDINGS STILL SHOW SOLID SUBFREEZING
SOUNDINGS WITH MOD-HVY SNOW ALONG A MANKATO-MINNEAPOLIS-BARRON
LINE WHERE 6-9 INCHES OF ACCUMULATION IS CERTAINLY WITHIN REASON
IN THIS FORECAST. GOING FURTHER E AND W...ACCUMULATIONS DROP OFF
IN A RATHER TIGHT GRADIENT...SUCH THAT NWRN PORTIONS OF THE MPX
CWFA MAY NOT EVEN SEE 1 INCH. THAT SAID...WPC GUIDANCE STILL PINS
A 8-10 INCH SWATH OF SNOWFALL OVER S-CENTRAL MN INTO E-CENTRAL MN
AND W-CENTRAL WI...AND WITH QPF NEARING AN INCH...EVEN SNOWFALL
RATIOS IN THE 4 OR 5 TO 1 AREA PRODUCE A STORM TOTAL OF 4-7
INCHES THRU TNGT WITH SLIGHT ADDITIONS FOR THU. NORMALLY THE
WARMER GROUND WOULD BE ABLE TO MELT THE SNOW AS IT FALLS...AND THE
WET NATURE OF THE SNOW WOULD ALSO HINDER ACCUMULATIONS. HOWEVER...
THE STRONG FGEN WITH HIGH SNOWFALL RATES FOR SEEM TO COMBAT THAT
THINKING IN THIS CASE...LEANING MORE TWD AGREEMENT WITH THE WPC
OUTPUT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 441 AM CDT WED MAY 1 2013
MODEL AGREEMENT THIS PERIOD REMAINS HIGH THROUGH FRIDAY...BUT
QUICKLY DISAPPEARS FROM FRIDAY NIGHT ONWARDS WITH HOW EACH MODEL
HANDLES THE PROGRESSION OF WHAT WILL BE A CUT OFF LOW THAT SETS UP
NEAR KANSAS CITY BY SATURDAY MORNING. ABOUT THE ONLY THING THERE IS
AGREEMENT ON BEYOND FRIDAY IS THAT HEIGHTS WILL SLOWLY MODIFY FROM
THE WEEKEND INTO NEXT WEEK...WHICH WILL ALLOW HIGHS TO WORK BACK
CLOSER TO EARLY MAY NORMALS.
FOR THURSDAY...FGEN INDUCED BAND OF HEAVY PRECIPITATION WILL
SLOWLY MOVE INTO WRN WI THU MORNING...AND LOOKS TO SPEND MOST OF
THE DAY CONFINED TO AREAS EAST OF AN ALBERT LEA TO RUSH CITY LINE.
GIVEN EXPECTED PERSISTENT PRECIPITATION AND CLOUD COVER...NUDGED
HIGHS DOWN INTO THE MID 30S FOR THURSDAY ACROSS ERN AREAS...WHICH
IS ABOUT 30 DEGREES BELOW NORMAL. OF COURSE THE OTHER IMPACT OF
THE COOLER TEMPS FOR THURSDAY IS THIS MAY ALLOW SNOW TO BE THE
PREDOMINATE P-TYPE FROM WED NIGHT RIGHT THROUGH THE DAY ON
THURSDAY. THE ONLY THING THAT HAS REALLY CHANGED IS A WESTWARD
SHIFT IN THE WARM NOSE BETWEEN H8 AND H7. THE GFS IN PARTICULAR
BRINGS THIS OUT TO ABOUT AN EAU CLAIRE TO LADYSMITH LINE...WITH A
PRETTY SHARP GRADIENT IN POTENTIAL SNOW TOTALS RESULTING ACROSS
THE ERN CWA...WITH VERY LITTLE ACCUMS AT AUGUSTA...WHILE A
MENOMONIE WOULD HAVE THE POTENTIAL FOR AROUND 8 INCHES. GIVEN THE
COOLER TEMPERATURES FOR THURSDAY AND THE POTENTIAL FOR CONTINUED
SNOW ACCUMS THROUGH THE DAY...WE DECIDED TO CARRY WINTER HEADLINES
THROUGH 00Z /7 PM THU/. AS WITH THE SHORT TERM...SNOW TOTALS ARE
TRICKY HERE AS GIVEN THE RATHER HIGH QPF NUMBERS...EVEN
POTENTIALLY UNREALISTIC SNOW RATIOS OF 4-6:1 STILL YIELD SNOWFALL
AMOUNTS THAT ARE OFF INTO UNCHARTED TERRITORY FOR MAY SNOWFALLS IN
THIS AREA. CURRENT GRIDS HAVE ABOUT A 100 MILE WIDE SWATH OF 6-9
INCHES OF SNOW THAT IS CENTERED ALONG A BLUE EARTH /CITY/...TO
HASTINGS...TO CUMBERLAND...WI LINE.
THOUGH CERTAINLY THE WARM SOILS/PAVEMENT TEMPS FROM THE RECENT
WARM SPELL WILL HAVE THE POTENTIAL TO LIMIT ACCUMULATIONS...
EXPECTED SNOWFALL RATES FROM TONIGHT INTO AT LEAST THURSDAY
MORNING IN THE 1-2 INCH PLUS RANGE WILL BE MORE THAN ENOUGH TO
ACCUMULATE ON ANY SURFACE WHILE THOSE TYPES OF RATES ARE BEING
OBSERVED. THERE IS CERTAINLY POTENTIAL FOR SNOWFALL AMOUNTS TO GO
EITHER WAY /HIGHER OR LOWER/ WITH THIS SYSTEM...BUT IF THE CURRENT
FORECAST DOES PAN OUT...THIS STORM WILL CERTAINLY BE RE- WRITING
THE RECORD BOOKS FOR MAY SNOWFALL ACROSS SOUTHERN MN AND WRN WI.
FOR THURSDAY NIGHT INTO FRIDAY...THE FOCUS FOR THE HEAVY
PRECIPITATION SHIFTS EAST FROM ERN IA INTO CENTRAL WI AS LLJ
SLOWLY SHIFTS EAST. AS RESULT...HAVE CUT BACK ON POPS IN THIS
PERIOD... ESPECIALLY ACROSS MN...WITH MUCH OF THE AREA LIKELY
SEEING A BIT OF A REPRIEVE FROM THE PRECIPITATION. IN
ADDITION...WRN MN WILL LIKELY SEE SOME FILTERED SUNSHINE...WHICH
WILL ALLOW WRN AREAS TO WARM BACK TOWARD THE 50S.
FOR FRIDAY NIGHT...MODEL DISAGREEMENTS START TO INCREASE
DRAMATICALLY WITH HANDLING OF A SURGE OF WAA ADVECTIVE PRECIP THAT
WILL BE COMING IN FROM THE SE AS A STRONG VORT MAX ROTATES
AROUND THE MAIN UPPER LOW OVER NRN MO /OFF THE NAM ANYWAYS/. THE
NAM IS THE MIDDLE MEMBER WITH THIS FEATURE...BRINGING ANOTHER
SHIELD OF HEAVY PRECIPITATION ACROSS THE MPX CWA FRIDAY NIGHT INTO
SATURDAY MORNING. THE GFS HAS A SIMILAR FEATURE...BUT KEEPS THE
BRUNT OF THE PRECIPITATION DOWN ACROSS IA. THE ECMWF HAS A
COMPLETELY DIFFERENT IDEA WITH HOW THIS UPPER LOW WILL EVOLVE.
WHERE THE GFS ON SAT HAS THE UPPER LOW OVER NRN ARK...THE NAM OVER
NRN MO...THE 01.00 ECMWF HAS THE SAME...MUCH SHALLOWER LOW UP NEAR
THE MN/DAKOTAS BORDER! GIVEN THE DISAGREEMENTS...HELD POPS TO NO
HIGHER THAN LIKELY ON SATURDAY AS IT COULD RANGE FROM ANYWHERE
BETWEEN A WASHOUT TO JUST COOL AND CLOUDY. AT THE VERY LEAST...AT
LEAST THIS POTENTIAL WAVE OF PRECIPITATION LOOKS TO BE WARM ENOUGH
TO KEEP EVERYTHING LIQUID.
GOING INTO NEXT WORK WEEK...BOTH THE GFS AND THE ECMWF SHOW
ANOTHER OMEGA BLOCK DEVELOPING...ONLY THIS TIME ACROSS THE WRN
US. THE ECMWF IS THE FARTHEST WEST WITH THIS FEATURE...WHICH
ALLOWS IT TO SEND ANOTHER STRONG SHORTWAVE AND COLD FRONT THROUGH
THE MPX AREA MONDAY NIGHT INTO TUESDAY. THE GFS HAS THE BLOCK
FARTHER EAST AND WOULD KEEP THE REGION DRY. AT THIS POINT...KEPT
THE MAINLY CHANCE POPS THAT WERE IN PLACE DURING THIS TIME FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 643 AM CDT WED MAY 1 2013
CDFNT WILL SETTLE S AND E OF THE AREA THRU TMRW MRNG WHILE SEVERAL
WAVES OF LOW PRES RIDE NE ALONG THE STALLED FRONT. SIGNIFICANT
INCRS IN MOISTURE FROM THE S WHILE WINDS SHIFT ARND TO NLY WILL
CREATE A WINTRY P-TYPE ISSUE ALONG WITH THE POTENTIAL FOR
SIGNIFICANT SNOW ACCUMULATION. PRECIP CURRENTLY MOVING SW-NE ACRS
SRN-CENTRAL MN INTO NW WI...MOSTLY AS -RA ALTHOUGH AM ALREADY
SEEING OBS REPORTING -SN...INCLUDING KRWF. COLDER AIR MAKING
STRONG PROGRESS INTO WRN AND SWRN MN...AND WILL CONTINUE TO MOVE E
THROUGH THE REST OF MN TDA AND INTO WI LATER THIS AFTN INTO TNGT.
THIS WILL GRADUALLY CHANGE OVER THE PRECIP FROM -RA TO -SN...AND
INTENSITIES MAY EASILY AND IN A SHORT DURATION INCRS FROM LGT TO
HVY...SIGNIFICANTLY IMPACTING VSBY WITH LITTLE ADVANCE NOTICE. THE
ONLY SITES EXPECTED TO GET AWAY UNSCATHED LOOKS TO BE KAXN-KSTC.
THE REST OF THE TAF SITES ARE EXPECTED TO SEE -RA CHANGING TO
-SN...WITH KEAU THE LAST. KMSP LOOKS TO BE THE MOST SIGNIFICANTLY
IMPACTED AS KMSP IS CENTERED WITHIN THE HEAVIEST BAND OF PRECIP.
AS ALL SITES CHANGE OVER TO -SN...BOTH CIGS AND VSBYS WILL BE
IMPACTED...LIKELY TO IFR...BUT THE TIMING IS STILL QUESTIONABLE SO
FREQUENT AMENDMENTS MAY BE NECESSARY.
KMSP...CONDS TO DETERIORATE STEADILY THRU THE DAY AS MOISTURE
SURGING FROM THE SW BRINGS RAIN...LGT TO MOD...TO THE FIELD THIS
MRNG. AS COLDER AIR SHIFTS SE INTO THE AREA...THE PRECIP WILL
CHANGE OVER TO -SN BY LATE AFTN. COULD BE AN ABRUPT CHANGEOVER AT
TIMES...THE TIMING OF WHICH COULD BE QUITE TROUBLESOME TO PIN
DOWN. HENCE THE INCLUSION OF SEVERAL TEMPO GROUPS THROUGH THE
FIRST HALF OF THE 01/12Z TAF. PRECIP IS EXPECTED TO FULLY CHANGE
OVER TO SNOW BY LATE AFTN...AND THE SNOW WILL THEN PERSIST
OVERNIGHT THRU TMRW MRNG. WILL LOOK FOR A POTENTIALLY SIGNIFICANT
SNOWFALL ACCUMULATION OF WET SNOW...AND MAY OCCUR RAPIDLY AT TIMES
WITH RATES OF 1-2 INCHES PER HOUR POSSIBLE. CONDS WILL GRADUALLY
IMPROVE LATE TMRW MRNG INTO TMRW AFTN AS THE STALLED CDFNT SHIFTS
AWAY.
/OUTLOOK FOR KMSP/
FRI...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA/-SN. NE WINDS 10-15
KT.
SAT...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA. ENE WINDS 5 KT.
SUN...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA. LGT/VRBL WINDS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR MNZ053-060>063-067>070-074>078-082>085-091>093.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR MNZ044-045-051-052-058-059-065-066-073.
WI...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR WIZ014>016-023>025.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR WIZ026>028.
&&
$$
UPDATE...JPC
SHORT TERM...JPC
LONG TERM...MPG
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
452 AM CDT WED MAY 1 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 441 AM CDT WED MAY 1 2013
NOT THE TYPICAL MAY FORECAST. CDFNT HAS SETTLED OVER SE WI AND
STRETCHES SWWD INTO CENTRAL AND SRN IA...AND WILL REMAIN QUASI-
STNRY OVER THESE AREAS THRU THE NEXT 24 HRS. SIGNIFICANT CAA IS IN
PROGRESS AS EVIDENCED BY TEMPS IN THE LOW 30S IN NRN AND WRN MN
WHILE THE ERN AND SRN MN INTO WRN WI IS IN THE 40S AND 50S. A
POTENT UPR LEVEL TROF WILL STALL OUT OVER THE NRN PLAINS AND UPR
MISS RIVER VALLEY...DIGGING FURTHER S AND SLIGHTLY PIVOTING TO
ENHANCE LIFT AND ALSO ALLOW A PROLONGED STREAM OF SRN MOISTURE TO
ADVECT WELL N INTO THIS REGION...DEEPENING THE MOISTURE COLUMN.
PWATS SURGE TO WELL OVER AN INCH THRU TNGT. IN ADDITION...MOST
RAIN/SNOW LAYER THRESHOLDS BECOME MUCH SHORTER PER BUFKIT PROFILES
BY LATE AFTN...INDICATING THAT THE PRECIP FALLING WILL TAKE THE
FORM OF SNOW RATHER THAN RAIN...HIGHLY UNUSUAL FOR THE MONTH OF
MAY. IN FACT...LOCAL HOPWRF GUIDANCE SHOWS SEVERAL SWATHS OF 1-3
IN/HR SNOW BANDS INTO CENTRAL-ERN MN BY MIDDAY WHICH MAKES SENSE
GIVEN THAT SPC SREF AND RAP GUIDANCE INDICATES VERY STRONG H7
FGEN. THE MAIN CONCERN IS THAT DEWPOINTS ARE STILL IN THE LOWER
20S WHERE TEMPS HAVE DROPPED TO THE FREEZING MARK. SHOULD
WETBULBING EFFECTS OCCUR...DROPPING THE TEMP FASTER THAN
ADVERTISED AND KEEPING IT THERE...ACCUMULATIONS COULD OCCUR
QUICKER AND EARLIER THAN ADVERTISED DESPITE THE WARM ROAD SFC
TEMPS OF THE PAST SEVERAL DAYS. COULD SEE 1-3 INCHES OF SOLID
ACCUMULATION THIS AFTN ONCE THE RAIN CHANGES OVER TO SNOW AND
INTENSITY IS MOD-HVY. WILL STILL LOOK FOR TEMPS TO FALL THRU THE
DAY TDA AND TNGT AS THE UPR TROF CONTINUES TO DIG OVER THE DAKOTAS
AND SFC WINDS SHIFT TO NW-N. GOING INTO TNGT...AT LEAST ONE HVY
BAND OF SNOW IS EXPECTED TO DEVELOP FROM NRN IA INTO SRN AND SE
MN...WITH STRONG FGEN OVER THIS SAME AREA LASTING THROUGH
DAYBREAK ON THU. BUFKIT SOUNDINGS STILL SHOW SOLID SUBFREEZING
SOUNDINGS WITH MOD-HVY SNOW ALONG A MANKATO-MINNEAPOLIS-BARRON
LINE WHERE 6-9 INCHES OF ACCUMULATION IS CERTAINLY WITHIN REASON
IN THIS FORECAST. GOING FURTHER E AND W...ACCUMULATIONS DROP OFF
IN A RATHER TIGHT GRADIENT...SUCH THAT NWRN PORTIONS OF THE MPX
CWFA MAY NOT EVEN SEE 1 INCH. THAT SAID...WPC GUIDANCE STILL PINS
A 8-10 INCH SWATH OF SNOWFALL OVER S-CENTRAL MN INTO E-CENTRAL MN
AND W-CENTRAL WI...AND WITH QPF NEARING AN INCH...EVEN SNOWFALL
RATIOS IN THE 4 OR 5 TO 1 AREA PRODUCE A STORM TOTAL OF 4-7
INCHES THRU TNGT WITH SLIGHT ADDITIONS FOR THU. NORMALLY THE
WARMER GROUND WOULD BE ABLE TO MELT THE SNOW AS IT FALLS...AND THE
WET NATURE OF THE SNOW WOULD ALSO HINDER ACCUMULATIONS. HOWEVER...
THE STRONG FGEN WITH HIGH SNOWFALL RATES FOR SEEM TO COMBAT THAT
THINKING IN THIS CASE...LEANING MORE TWD AGREEMENT WITH THE WPC
OUTPUT.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 441 AM CDT WED MAY 1 2013
MODEL AGREEMENT THIS PERIOD REMAINS HIGH THROUGH FRIDAY...BUT
QUICKLY DISAPPEARS FROM FRIDAY NIGHT ONWARDS WITH HOW EACH MODEL
HANDLES THE PROGRESSION OF WHAT WILL BE A CUT OFF LOW THAT SETS UP
NEAR KANSAS CITY BY SATURDAY MORNING. ABOUT THE ONLY THING THERE IS
AGREEMENT ON BEYOND FRIDAY IS THAT HEIGHTS WILL SLOWLY MODIFY FROM
THE WEEKEND INTO NEXT WEEK...WHICH WILL ALLOW HIGHS TO WORK BACK
CLOSER TO EARLY MAY NORMALS.
FOR THURSDAY...FGEN INDUCED BAND OF HEAVY PRECIPITATION WILL
SLOWLY MOVE INTO WRN WI THU MORNING...AND LOOKS TO SPEND MOST OF
THE DAY CONFINED TO AREAS EAST OF AN ALBERT LEA TO RUSH CITY LINE.
GIVEN EXPECTED PERSISTENT PRECIPITATION AND CLOUD COVER...NUDGED
HIGHS DOWN INTO THE MID 30S FOR THURSDAY ACROSS ERN AREAS...WHICH
IS ABOUT 30 DEGREES BELOW NORMAL. OF COURSE THE OTHER IMPACT OF
THE COOLER TEMPS FOR THURSDAY IS THIS MAY ALLOW SNOW TO BE THE
PREDOMINATE P-TYPE FROM WED NIGHT RIGHT THROUGH THE DAY ON
THURSDAY. THE ONLY THING THAT HAS REALLY CHANGED IS A WESTWARD
SHIFT IN THE WARM NOSE BETWEEN H8 AND H7. THE GFS IN PARTICULAR
BRINGS THIS OUT TO ABOUT AN EAU CLAIRE TO LADYSMITH LINE...WITH A
PRETTY SHARP GRADIENT IN POTENTIAL SNOW TOTALS RESULTING ACROSS
THE ERN CWA...WITH VERY LITTLE ACCUMS AT AUGUSTA...WHILE A
MENOMONIE WOULD HAVE THE POTENTIAL FOR AROUND 8 INCHES. GIVEN THE
COOLER TEMPERATURES FOR THURSDAY AND THE POTENTIAL FOR CONTINUED
SNOW ACCUMS THROUGH THE DAY...WE DECIDED TO CARRY WINTER HEADLINES
THROUGH 00Z /7 PM THU/. AS WITH THE SHORT TERM...SNOW TOTALS ARE
TRICKY HERE AS GIVEN THE RATHER HIGH QPF NUMBERS...EVEN
POTENTIALLY UNREALISTIC SNOW RATIOS OF 4-6:1 STILL YIELD SNOWFALL
AMOUNTS THAT ARE OFF INTO UNCHARTED TERRITORY FOR MAY SNOWFALLS IN
THIS AREA. CURRENT GRIDS HAVE ABOUT A 100 MILE WIDE SWATH OF 6-9
INCHES OF SNOW THAT IS CENTERED ALONG A BLUE EARTH /CITY/...TO
HASTINGS...TO CUMBERLAND...WI LINE.
THOUGH CERTAINLY THE WARM SOILS/PAVEMENT TEMPS FROM THE RECENT
WARM SPELL WILL HAVE THE POTENTIAL TO LIMIT ACCUMULATIONS...
EXPECTED SNOWFALL RATES FROM TONIGHT INTO AT LEAST THURSDAY
MORNING IN THE 1-2 INCH PLUS RANGE WILL BE MORE THAN ENOUGH TO
ACCUMULATE ON ANY SURFACE WHILE THOSE TYPES OF RATES ARE BEING
OBSERVED. THERE IS CERTAINLY POTENTIAL FOR SNOWFALL AMOUNTS TO GO
EITHER WAY /HIGHER OR LOWER/ WITH THIS SYSTEM...BUT IF THE CURRENT
FORECAST DOES PAN OUT...THIS STORM WILL CERTAINLY BE RE- WRITING
THE RECORD BOOKS FOR MAY SNOWFALL ACROSS SOUTHERN MN AND WRN WI.
FOR THURSDAY NIGHT INTO FRIDAY...THE FOCUS FOR THE HEAVY
PRECIPITATION SHIFTS EAST FROM ERN IA INTO CENTRAL WI AS LLJ
SLOWLY SHIFTS EAST. AS RESULT...HAVE CUT BACK ON POPS IN THIS
PERIOD... ESPECIALLY ACROSS MN...WITH MUCH OF THE AREA LIKELY
SEEING A BIT OF A REPRIEVE FROM THE PRECIPITATION. IN
ADDITION...WRN MN WILL LIKELY SEE SOME FILTERED SUNSHINE...WHICH
WILL ALLOW WRN AREAS TO WARM BACK TOWARD THE 50S.
FOR FRIDAY NIGHT...MODEL DISAGREEMENTS START TO INCREASE
DRAMATICALLY WITH HANDLING OF A SURGE OF WAA ADVECTIVE PRECIP THAT
WILL BE COMING IN FROM THE SE AS A STRONG VORT MAX ROTATES
AROUND THE MAIN UPPER LOW OVER NRN MO /OFF THE NAM ANYWAYS/. THE
NAM IS THE MIDDLE MEMBER WITH THIS FEATURE...BRINGING ANOTHER
SHIELD OF HEAVY PRECIPITATION ACROSS THE MPX CWA FRIDAY NIGHT INTO
SATURDAY MORNING. THE GFS HAS A SIMILAR FEATURE...BUT KEEPS THE
BRUNT OF THE PRECIPITATION DOWN ACROSS IA. THE ECMWF HAS A
COMPLETELY DIFFERENT IDEA WITH HOW THIS UPPER LOW WILL EVOLVE.
WHERE THE GFS ON SAT HAS THE UPPER LOW OVER NRN ARK...THE NAM OVER
NRN MO...THE 01.00 ECMWF HAS THE SAME...MUCH SHALLOWER LOW UP NEAR
THE MN/DAKOTAS BORDER! GIVEN THE DISAGREEMENTS...HELD POPS TO NO
HIGHER THAN LIKELY ON SATURDAY AS IT COULD RANGE FROM ANYWHERE
BETWEEN A WASHOUT TO JUST COOL AND CLOUDY. AT THE VERY LEAST...AT
LEAST THIS POTENTIAL WAVE OF PRECIPITATION LOOKS TO BE WARM ENOUGH
TO KEEP EVERYTHING LIQUID.
GOING INTO NEXT WORK WEEK...BOTH THE GFS AND THE ECMWF SHOW
ANOTHER OMEGA BLOCK DEVELOPING...ONLY THIS TIME ACROSS THE WRN
US. THE ECMWF IS THE FARTHEST WEST WITH THIS FEATURE...WHICH
ALLOWS IT TO SEND ANOTHER STRONG SHORTWAVE AND COLD FRONT THROUGH
THE MPX AREA MONDAY NIGHT INTO TUESDAY. THE GFS HAS THE BLOCK
FARTHER EAST AND WOULD KEEP THE REGION DRY. AT THIS POINT...KEPT
THE MAINLY CHANCE POPS THAT WERE IN PLACE DURING THIS TIME FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1058 PM CDT TUE APR 30 2013
RAIN CHANCES WILL BE ON THE INCREASE TONIGHT...WITH CIGS EXPECTED
TO LOWER TO MVFR CATEGORY OVERNIGHT AND EARLY WEDNESDAY MORNING AT
KMSP/KRNH/KEAU. CONVERSELY...CONDITIONS AT KAXN AND KSTC ARE
EXPECTED TO REMAIN VFR THROUGH THE PERIOD/EVENT. THERE/S STILL
UNCERTAINTY AS TO WHEN THE CHANGEOVER TO SNOW WILL BE...BUT LATE
MORNING AND EARLY AFTERNOON IN MN...AND EARLY EVE IN WI...SEEM
LIKE REASONABLE TIME FRAMES. MVFR CIGS/VSBYS WITH OCCASIONAL IFR
VSBYS IN -SN ARE THEN EXPECTED INTO THURSDAY. WINDS OF 330-360
DEGREES WILL PREVAIL THROUGH THE PERIOD...WITH GUSTS UP TO 20 KTS
DEVELOPING WEDNESDAY.
KMSP...
PRETTY MUCH STATUS QUO IN THE TAF. STILL EXPECTING TO MIX SOME
FLAKES IN WITH THE RAIN DURING THE DAY ON WEDNESDAY. THERE IS
STILL A FAIR AMOUNT OF UNCERTAINTY IN HOW FAST WE COOL FOR THE
TRANSITION TO SNOW. AT ANY RATE...EVEN IF SNOW BEGINS IN THE
MORNING...LITTLE TO NO ACCUMULATION IS EXPECTED GIVEN THE WARM
GROUND AND RELATIVELY LIGHT INTENSITY OF PRECIPITATION. ONCE THE
SNOW BEGINS...VSBY REDUCTIONS TO IFR WILL BE POSSIBLE. WINDS FROM
320-350 DEGREES AOB 11 KTS THROUGH WEDNESDAY...THEN GUSTS TO 20
KTS DEVELOPING WEDNESDAY EVE.
/OUTLOOK FOR KMSP/
THU...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA/-SN. NW WINDS 15 KT.
FRI...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA/-SN. NE WINDS 10-15
KT.
SAT...MVFR CIGS/VSBYS POSSIBLE WITH CHC -RA. ENE WINDS 5 KT.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR MNZ053-060>063-067>070-074>078-082>085-091>093.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR MNZ044-045-051-052-058-059-065-066-073.
WI...WINTER STORM WARNING FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR WIZ014>016-023>025.
WINTER WEATHER ADVISORY FROM 3 PM THIS AFTERNOON TO 7 PM CDT
THURSDAY FOR WIZ026>028.
&&
$$
SHORT TERM...JPC
LONG TERM...MPG
AVIATION...LS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1137 PM EDT THU MAY 2 2013
.SYNOPSIS...
INTERVALS OF LIGHT RAIN AND DRIZZLE WILL CONTINUE TO MOVE ONSHORE
FROM TIME TO TIME THROUGH SATURDAY. A MORE SIGNIFICANT STORM
SYSTEM WILL AFFECT THE REGION NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 1115 PM THURSDAY...BASED ON LATEST KLTX AND SURROUNDING
88DS...AND THE LATEST HRRR OUTPUT AND THE 00Z NAM...THE BULK OF
THE PCPN IN THE FORM OF STRATIFORM R- AND L- TO REMAIN OVER
THE ADJACENT ATLANTIC WATERS. A TRAJECTORY RUNNING FROM ENE TO
WSW FROM THE CURRENT PCPN OVER THE ATL WATERS...WILL BRUSH ACROSS
THE COASTAL COUNTIES OVERNIGHT. WILL THE SLIGHT CHANCE ALONG THE
IMMEDIATE COAST FOR ANY ONSHORE MOVEMENT.
LATEST NAM MODEL AND GFS MOS INDICATES A RANGE OF LOWS FROM LOW TO MID
50S NE PORTIONS OF THE CWA TO MID AND UPPER 50S SOUTHERN PORTIONS.
DEWPOINTS ONLY A FEW TICKS BELOW TEMPS DURING THE OVERNIGHT. NE
WINDS TO STAY ACTIVE OVERNIGHT ALONG WITH INTERVALS OF
CLOUDS...THUS PREVENTING ANY FOG DEVELOPMENT. POCKETS OF DRIZZLE
ALONG THE IMMEDIATE COAST OVERNIGHT COULD TEMPORARILY BRING DOWN
VSBYS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...MAIN FORECAST CHALLENGE IS THE POSSIBILITY
OF THE INTERVALS OF NUISANCE RAIN/DRIZZLE CONTINUING FOR THE NEXT
COUPLE OF DAYS. ALTHOUGH THERMAL PROFILES CONTINUE TO DRY
OUT...THE FACT THAT THE NATURE OF THE SHOWERS HAS BEEN AND IS VERY
SHALLOW. THIS ALMOST GOES WITHOUT SAYING WITH DRIZZLE. THE
GFS...NAM AS WELL AS SREF PLUME DIAGRAMS SHOW SMALL AREAS OF QPF
INDICATIVE OF THIS ACTIVITY CONTINUING THROUGH
SATURDAY...THEREFORE...I HAVE ADDED THIS TO THE FORECAST. TIMING
IS DIFFICULT BUT LEANED TOWARD THE NAM TO SHOW AN INCREMENTAL
DIFFERENCE WITH A SLIGHT INCREASE BOTH FRIDAY AND SATURDAY
MORNINGS. ONLY SMALL CHANGES TO TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...CLIMATOLOGICALLY UNUSUAL SETUP THROUGH MOST OF
THE PERIOD MAKING FOR SOME INTERESTING AND CHALLENGING FORECASTS.
DEEP CUTOFF UPPER LOW WILL APPROACH AND EVENTUALLY TRAVERSE THE
CAROLINAS...WHICH IS MUCH MORE TYPICAL OF WINTER OR MUCH EARLIER IN
THE SPRING. IT IS MORE THE ISOLATION FROM THE FLOW OF THIS FEATURE
RATHER THAN ITS UNUSUAL TIMING THAT MAKES THE FORECAST CHALLENGING
SINCE SUCH FEATURES ARE USUALLY POORLY HANDLED BY MODEL GUIDANCE.
THAT SAID THE MODELS HAVE COME INTO PRETTY GOOD AGREEMENT WITH THE
EVOLUTION OF THE PATTERN. THERE WILL STILL BE SOME FUTURE
REFINEMENTS IN THE TIMING POSSIBLE AND THE WEATHER ITSELF WILL BE
QUITE COMPLEX AS WE SHOULD GO THROUGH SOME DISTINCT REGIME CHANGES
THROUGH THE PERIOD. SUNDAY APPEARS TO BE THE LAST DAY IN THE
PRE FRONTAL FLOW AHEAD OF THE UPPER LOW. MOISTURE WILL BE RAPIDLY ON
THE RISE ESP ACCORDING TO THE RELATIVELY FASTER GFS. BEST FORCING IN
THE FORM OF MID LEVEL JETTING AND HEIGHT FALLS COME EITHER LATE
SUNDAY OR SUNDAY NIGHT INTO MONDAY AGAIN DEPENDING ON MODEL SOLN.
RAINFALL CHANCES AND QPF POTENTIAL ARE STARTING TO LOOK PRETTY GOOD
WITH SUCH STRONG FORCING AND DEEP ATLANTIC MOISTURE EXPECTED. THEN
THE SYNOPTIC SCALE DRY SLOT WILL MOVE ACROSS THE AREA SHUTTING OFF
THE RAINFALL FOR ABOUT A PERIOD. WE WILL THEN MOVE INTO A VERY
CONVECTIVE REGIME AS THE COLD POOL ALOFT CRAWLS ACROSS THE REGION.
RIGHT NOW BEST ESTIMATE IS THIS IS TUESDAY...WHICH COULD BE A BUSY
DAY WITH A RADAR SCOPE FULL OF SMALL HAIL PRODUCING SHALLOW TSTMS.
RAIN CHANCES WILL BE SMALLER FOR THE REMAINDER OF THE PERIOD AS THE
SLOW MOVING SYSTEM COULD STILL PLAGUE THE COASTAL CAROLINAS WITH
WRAP-AROUND MOISTURE.
&&
.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...LIGHT PRECIPITATION IS DECREASING IN AERIAL COVERAGE
THIS EVENING. CIGS AND VSBYS ARE CURRENTLY VFR.
HIGH PRESSURE WILL CONTINUE ACROSS THE TERMINALS THIS TAF VALID
PERIOD RESULTING IN CONTINUE A ENE-E LOW-MID LEVEL FLOW. ALL
MODELS ARE IN AGREEMENT THAT DRIER AIR IN THE MID LEVELS WILL MOVE
INTO THE TERMINALS THIS EVENING FROM THE NORTHEAST AND PERSIST
OVERNIGHT. THIS SHOULD LIMIT ANY PRECIPITATION THROUGH THE
OVERNIGHT HOURS. THERE IS MODERATE TO HIGH CONFIDENCE MVFR CIGS
WILL DEVELOP AS ADVERTISED IN TAFS...WITH THE LOWEST CONFIDENCE
IN TIMING. WILL INCLUDE TEMPO IFR CIGS WITH THIS TAF ISSUANCE AT
ALL TERMINALS EXCEPT KLBT...BUT DRIER MID LEVEL AIR COUPLED WITH
WARMER SURFACE TEMPERATURES AT THE COASTAL TERMINALS COULD LIMIT
IFR POTENTIAL AT THE COASTAL TERMINALS.
MVFR CONDITIONS WILL BE LIKELY AT ALL TERMINALS THROUGH THE
MORNING HOURS. ALL MODELS SUGGEST INCREASING MID LEVEL MOISTURE
AFTER 15Z. THIS COULD INCREASE THE CHANCES OF PRECIPITATION
ESPECIALLY AT THE COASTAL TERMINALS THUS WILL INDICATE VCSH IN
TAFS. SOME OF THIS PRECIPITATION COULD MOVE WEST TO THE INLAND
TERMINALS IN THE AFTERNOON.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS ESPECIALLY COASTAL
TERMINALS THROUGH SUNDAY. IFR/MVFR EARLY SUNDAY WITH RAIN/ISOLATED
THUNDERSTORMS DEVELOPING SUNDAY EVENING PERSISTING THROUGH MONDAY.
MVFR/TEMPO IFR POSSIBLE. VFR/TEMPO MVFR WITH SCATTERED SHOWERS
TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1115 PM THURSDAY...SCA EXTENDED FOR ALL WATERS TO 6 PM
SATURDAY...MAY 4TH.
PERSISTENCE THE WORD HERE FOR WINDS. CURRENT NE WINDS BASICALLY
REMAIN AT THESE SPEEDS FOR THE OVERNIGHT PERIOD. OF NOTE...HRRR
AND NAM INDICATE A MORE EASTERLY WIND DIRECTION AND 3 TO 5 KT
SUSTAINED HIER SPEEDS FOR THE ADJACENT OFFSHORE WATERS. THIS WILL
LIKELY HAVE IMPLICATIONS ON SIGNIFICANT SEAS
OVERNIGHT...ESPECIALLY THE OUTER WATERS OFF THE CAPES...FEAR AND
ROMAIN. OVERALL...HAVE INCREASED SIGNIFICANT SEAS BY 1
FOOT...HIGHEST AT 8 FT...ACROSS ALL WATERS...AND WOULD NOT BE
SURPRISED TO OBSERVE 2 FT HIER...HIGHEST AT 9 FT...MAINLY ACROSS
THE OUTER WATERS 15 TO 20 NM OUT FROM THE CAPES. AVERAGE PERIODS
OVERNIGHT WILL RUN 5 TO 6 SECONDS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...PERSISTENT NORTHEAST FLOW CONTINUES THROUGH
THE PERIOD. THERE MAY BE A LITTLE VEERING VERY LATE IN THE PERIOD
TO MORE OF A EASTERLY FLOW BUT OVERALL...THE NE FLOW WILL BE THE
STORY. STRONGEST WINDS WILL OCCUR FRIDAY WITH A FEW AREAS ACROSS
THE OUTER WATERS POSSIBLY EXCEEDING 25 KNOTS. FOR NOW THINK THESE
SPEEDS WILL BE LIMITED IN DURATION TO KEEP GALE CONSIDERATION IN
CHECK. SEAS WILL REMAIN RUGGED THROUGH THE PERIOD AND WILL ALMOST
CERTAINLY SEE THE SMALL CRAFT ADVISORY CONTINUE.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...FAIRLY COMPLEX AND ACTIVE WEATHER EXPECTED FOR
MOST OF THE PERIOD ESPECIALLY EARLY ON. A DEEPLY CUTOFF UPPER SYSTEM
WILL APPROACH FROM THE WEST ON SUNDAY WITH A COLD FRONT ALONG ITS
LEADING EDGE. ONSHORE/EASTERLY FLOW WILL GET PINCHED BY THIS
APPROACHING BOUNDARY AS HIGH PRESSURE NOSED INTO THE CAROLINAS TRIES
TO HOLD ITS GROUND. AT SOME POINT THERE SHOULD BE SOME PRETTY SHARP
VEERING AS THE HIGH LOSES GROUND TO THE APPROACHING FRONT...AND THIS
IS PROBABLY THE MOST UNCERTAIN PART OF THE FORECAST. SOUTHERLY FLOW
SHOULD OVERSPREAD BY MONDAY WITH ADDITIONAL VEERING DUE TO THE
CYCLONIC CURVATURE OF THE ISOBARS COMING ACROSS THE CAROLINAS MONDAY
NIGHT INTO TUESDAY. ALL OF THE CHANGING OF THE WIND DIRECTION
THROUGH THE PERIOD SHOULD KEEP WAVE FACES RATHER STEEP AND PERIODS
SHORT MAKING FOR CHOPPY CONDITIONS. WHETHER OR NOT ANY CAUTIONARY
HEADLINES OR EVEN ADVISORIES ARE NEEDED TO TO WAVE HEIGHTS IS VERY
UNCERTAIN BUT WIND SPEEDS WILL REMAIN SHY OF EITHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR AMZ250-252-
254-256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...DCH
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
800 PM EDT THU MAY 2 2013
.SYNOPSIS...
INTERVALS OF LIGHT RAIN AND DRIZZLE WILL CONTINUE TO MOVE ONSHORE
FROM TIME TO TIME THROUGH SATURDAY. A MORE SIGNIFICANT STORM
SYSTEM WILL AFFECT THE REGION NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 615 PM THURSDAY...THIS UPDATE MAINLY CONCERNED WITH PCPN
COVERAGE THIS EVENING AND OVERNIGHT. BASED ON LATEST KLTX AND
SURROUNDING 88DS...AND THE LATEST HRRR OUTPUT...PCPN IN THE FORM
OF STRATIFORM R- AND L- TO MOVE FROM ENE TO WSW ACROSS THE FA
EARLY INTO THE MID-EVENING HOURS. WILL BASICALLY DROP POPS BELOW
15 PERCENT ACROSS INLAND LOCATIONS OVERNIGHT...BUT KEEP SLIGHT
CHANCE ALONG THE IMMEDIATE COAST FOR ANY ONSHORE MOVEMENT. NO
CHANGES TO OVERNIGHT TEMPS AT THIS POINT.
PREVIOUS DISCUSSION..................................
AS OF 230 PM THURSDAY...MOIST NORTHEASTERLY FLOW WILL CONTINUE
THROUGH THE NEAR TERM AS HIGH PRESSURE PRESSES DOWN FROM THE
NORTH. LOW LEVEL CONVERGENCE ALONG THE COAST ALLOWING PATCHES OF
LIGHT RAIN AND DRIZZLE TO FORM AND MOVE INLAND. THIS PATTERN WILL
CONTINUE FOR THE REMAINDER OF THE AFTERNOON. NOT MUCH CHANGES FOR
TONIGHT OTHER THAN SOME ADDITIONAL DRYING AT THE MID LEVELS.
HOWEVER...AS PRESENT PRECIPITATION REGIME IS PRIMARILY A STRATUS
EVENT...WILL BE KEEPING IN THE CHANCE FOR ADDITIONAL LIGHT RAIN
AND DRIZZLE INTO THE NIGHT-TIME HOURS...WITH THE BEST CHANCES
ALONG THE COAST. A CONSENSUS OF GUIDANCE GIVES US OVERNIGHT
TEMPERATURES NOT FAR FROM CLIMO...MID 50S INLAND AND UPPER 50S
CLOSER TO THE COAST.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...MAIN FORECAST CHALLENGE IS THE POSSIBILITY
OF THE INTERVALS OF NUISANCE RAIN/DRIZZLE CONTINUING FOR THE NEXT
COUPLE OF DAYS. ALTHOUGH THERMAL PROFILES CONTINUE TO DRY
OUT...THE FACT THAT THE NATURE OF THE SHOWERS HAS BEEN AND IS VERY
SHALLOW. THIS ALMOST GOES WITHOUT SAYING WITH DRIZZLE. THE
GFS...NAM AS WELL AS SREF PLUME DIAGRAMS SHOW SMALL AREAS OF QPF
INDICATIVE OF THIS ACTIVITY CONTINUING THROUGH
SATURDAY...THEREFORE...I HAVE ADDED THIS TO THE FORECAST. TIMING
IS DIFFICULT BUT LEANED TOWARD THE NAM TO SHOW AN INCREMENTAL
DIFFERENCE WITH A SLIGHT INCREASE BOTH FRIDAY AND SATURDAY
MORNINGS. ONLY SMALL CHANGES TO TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...CLIMATOLOGICALLY UNUSUAL SETUP THROUGH MOST OF
THE PERIOD MAKING FOR SOME INTERESTING AND CHALLENGING FORECASTS.
DEEP CUTOFF UPPER LOW WILL APPROACH AND EVENTUALLY TRAVERSE THE
CAROLINAS...WHICH IS MUCH MORE TYPICAL OF WINTER OR MUCH EARLIER IN
THE SPRING. IT IS MORE THE ISOLATION FROM THE FLOW OF THIS FEATURE
RATHER THAN ITS UNUSUAL TIMING THAT MAKES THE FORECAST CHALLENGING
SINCE SUCH FEATURES ARE USUALLY POORLY HANDLED BY MODEL GUIDANCE.
THAT SAID THE MODELS HAVE COME INTO PRETTY GOOD AGREEMENT WITH THE
EVOLUTION OF THE PATTERN. THERE WILL STILL BE SOME FUTURE
REFINEMENTS IN THE TIMING POSSIBLE AND THE WEATHER ITSELF WILL BE
QUITE COMPLEX AS WE SHOULD GO THROUGH SOME DISTINCT REGIME CHANGES
THROUGH THE PERIOD. SUNDAY APPEARS TO BE THE LAST DAY IN THE
PRE FRONTAL FLOW AHEAD OF THE UPPER LOW. MOISTURE WILL BE RAPIDLY ON
THE RISE ESP ACCORDING TO THE RELATIVELY FASTER GFS. BEST FORCING IN
THE FORM OF MID LEVEL JETTING AND HEIGHT FALLS COME EITHER LATE
SUNDAY OR SUNDAY NIGHT INTO MONDAY AGAIN DEPENDING ON MODEL SOLN.
RAINFALL CHANCES AND QPF POTENTIAL ARE STARTING TO LOOK PRETTY GOOD
WITH SUCH STRONG FORCING AND DEEP ATLANTIC MOISTURE EXPECTED. THEN
THE SYNOPTIC SCALE DRY SLOT WILL MOVE ACROSS THE AREA SHUTTING OFF
THE RAINFALL FOR ABOUT A PERIOD. WE WILL THEN MOVE INTO A VERY
CONVECTIVE REGIME AS THE COLD POOL ALOFT CRAWLS ACROSS THE REGION.
RIGHT NOW BEST ESTIMATE IS THIS IS TUESDAY...WHICH COULD BE A BUSY
DAY WITH A RADAR SCOPE FULL OF SMALL HAIL PRODUCING SHALLOW TSTMS.
RAIN CHANCES WILL BE SMALLER FOR THE REMAINDER OF THE PERIOD AS THE
SLOW MOVING SYSTEM COULD STILL PLAGUE THE COASTAL CAROLINAS WITH
WRAP-AROUND MOISTURE.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
AS OF 00Z...LIGHT PRECIPITATION IS DECREASING IN AERIAL COVERAGE
THIS EVENING. CIGS AND VSBYS ARE CURRENTLY VFR.
HIGH PRESSURE WILL CONTINUE ACROSS THE TERMINALS THIS TAF VALID
PERIOD RESULTING IN CONTINUE A ENE-E LOW-MID LEVEL FLOW. ALL
MODELS ARE IN AGREEMENT THAT DRIER AIR IN THE MID LEVELS WILL MOVE
INTO THE TERMINALS THIS EVENING FROM THE NORTHEAST AND PERSIST
OVERNIGHT. THIS SHOULD LIMIT ANY PRECIPITATION THROUGH THE
OVERNIGHT HOURS. THERE IS MODERATE TO HIGH CONFIDENCE MVFR CIGS
WILL DEVELOP AS ADVERTISED IN TAFS...WITH THE LOWEST CONFIDENCE
IN TIMING. WILL INCLUDE TEMPO IFR CIGS WITH THIS TAF ISSUANCE AT
ALL TERMINALS EXCEPT KLBT...BUT DRIER MID LEVEL AIR COUPLED WITH
WARMER SURFACE TEMPERATURES AT THE COASTAL TERMINALS COULD LIMIT
IFR POTENTIAL AT THE COASTAL TERMINALS.
MVFR CONDITIONS WILL BE LIKELY AT ALL TERMINALS THROUGH THE
MORNING HOURS. ALL MODELS SUGGEST INCREASING MID LEVEL MOISTURE
AFTER 15Z. THIS COULD INCREASE THE CHANCES OF PRECIPITATION
ESPECIALLY AT THE COASTAL TERMINALS THUS WILL INDICATE VCSH IN
TAFS. SOME OF THIS PRECIPITATION COULD MOVE WEST TO THE INLAND
TERMINALS IN THE AFTERNOON.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS ESPECIALLY COASTAL
TERMINALS THROUGH SUNDAY. IFR/MVFR EARLY SUNDAY WITH RAIN/ISOLATED
THUNDERSTORMS DEVELOPING SUNDAY EVENING PERSISTING THROUGH MONDAY.
MVFR/TEMPO IFR POSSIBLE. VFR/TEMPO MVFR WITH SCATTERED SHOWERS
TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 615 PM THURSDAY...PERSISTENCE THE WORD HERE...CURRENT WIND
AND SEA CONDITIONS REMAIN WITHIN THE CONSTRAINTS OF THE CURRENT
FORECAST. SEE NO CHANGES NEEDED AT THIS TIME. THE NEXT UPDATE MAY
WARRANT THE EXTENSION OF THE SCA OUT FURTHER IN TIME...IF MODEL
CONSENSUS REMAINS UNCHANGED.
PREVIOUS DISCUSSION..................................
AS OF 230 PM THURSDAY...HIGH PRESSURE PRESSING DOWN FROM THE NORTH
WILL KEEP UP A STEADY NORTHEASTERLY FLOW IN THE PRESENT 15 TO 20
KT RANGE. SEAS WILL WILL NOT STRAY FROM PRESENT 4 TO 7 FT
RANGE...SO EXPECT TO KEEP SMALL CRAFT ADVISORY IN EFFECT THROUGH
THE NEAR TERM.
ADVISORY FLAGS REMAIN FLAPPING ACROSS ALL MARINE ZONES FOR 25 KT
GUSTS AND 4-7 FOOT SEAS. STRONG HIGH PRESSURE NORTH OF THE WATERS
WILL CONTINUE TO PRESS SOUTHWARD. LOWER PRESSURE ACROSS FLORIDA
INTERACTING WITH THE HIGH WILL KEEP THE MSLP GRADIENT TIGHT WITH
BLUSTERY NE-E WINDS EXPECTED THROUGH TONIGHT. E WAVES OF 4-7 FEET
WILL RUN IN WAVE INTERVALS OF 6-8 SECONDS RESULTING IN STEEP-FACED
AND TREACHEROUS WAVES. ISOLATED SHOWERS WILL TRACK FROM EAST TO
WEST AND ONSHORE TODAY BUT NO TSTMS OR WIDESPREAD RESTRICTIONS TO
VISIBILITY ARE ANTICIPATED.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...PERSISTENT NORTHEAST FLOW CONTINUES THROUGH
THE PERIOD. THERE MAY BE A LITTLE VEERING VERY LATE IN THE PERIOD
TO MORE OF A EASTERLY FLOW BUT OVERALL...THE NE FLOW WILL BE THE
STORY. STRONGEST WINDS WILL OCCUR FRIDAY WITH A FEW AREAS ACROSS
THE OUTER WATERS POSSIBLY EXCEEDING 25 KNOTS. FOR NOW THINK THESE
SPEEDS WILL BE LIMITED IN DURATION TO KEEP GALE CONSIDERATION IN
CHECK. SEAS WILL REMAIN RUGGED THROUGH THE PERIOD AND WILL ALMOST
CERTAINLY SEE THE SMALL CRAFT ADVISORY CONTINUE.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...FAIRLY COMPLEX AND ACTIVE WEATHER EXPECTED FOR
MOST OF THE PERIOD ESPECIALLY EARLY ON. A DEEPLY CUTOFF UPPER SYSTEM
WILL APPROACH FROM THE WEST ON SUNDAY WITH A COLD FRONT ALONG ITS
LEADING EDGE. ONSHORE/EASTERLY FLOW WILL GET PINCHED BY THIS
APPROACHING BOUNDARY AS HIGH PRESSURE NOSED INTO THE CAROLINAS TRIES
TO HOLD ITS GROUND. AT SOME POINT THERE SHOULD BE SOME PRETTY SHARP
VEERING AS THE HIGH LOSES GROUND TO THE APPROACHING FRONT...AND THIS
IS PROBABLY THE MOST UNCERTAIN PART OF THE FORECAST. SOUTHERLY FLOW
SHOULD OVERSPREAD BY MONDAY WITH ADDITIONAL VEERING DUE TO THE
CYCLONIC CURVATURE OF THE ISOBARS COMING ACROSS THE CAROLINAS MONDAY
NIGHT INTO TUESDAY. ALL OF THE CHANGING OF THE WIND DIRECTION
THROUGH THE PERIOD SHOULD KEEP WAVE FACES RATHER STEEP AND PERIODS
SHORT MAKING FOR CHOPPY CONDITIONS. WHETHER OR NOT ANY CAUTIONARY
HEADLINES OR EVEN ADVISORIES ARE NEEDED TO TO WAVE HEIGHTS IS VERY
UNCERTAIN BUT WIND SPEEDS WILL REMAIN SHY OF EITHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR AMZ250-252-254-
256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...DCH/REK
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
312 PM EDT WED MAY 1 2013
.SYNOPSIS...
HIGH PRESSURE WILL EXTEND DOWN THE EAST COAST THROUGH THE REMAINDER
OF THE WORK WEEK. LOW LEVEL NE FLOW WILL MAINTAIN A MOIST AIR MASS
THROUGH EARLY THURSDAY...AFTERWHICH DRIER AIR WILL OVERSPREAD THE
REGION.
&&
.NEAR TERM /TONIGHT/...
AS OF 312 PM WEDNESDAY...
TONIGHT...925-850MB FLOW VEERS THIS EVENING TO MORE OF A E-SE
DIRECTION. THIS UPSLOPE COMPONENT AND FETCH OFF THE ATLANTIC WILL
MAINTAIN LOW OVERCAST SKIES. ISENTROPIC LIFT IN THE 290-295K LAYER
SHOULD RESULT IN AREAS OF DRIZZLE AND POSSIBLY SOME POCKETS OF LIGHT
RAIN. GFS DEPICTS A DECENT POCKET OF LIFT OVER THE WESTERN PIEDMONT
LATE TONIGHT WHICH WOULD SUPPORT A GREATER CHANCE OF RAIN
OVERNIGHT. HRRR VERIFYING RELATIVELY WELL WITH ISOLATED/SCATTERED
SHOWERS ALONG IMMEDIATE COAST AND SPOTS OF LIGHT PRECIP INLAND. THIS
MODEL SUGGEST BULK OF VERY LIGHT PRECIP DEVELOPING OVER THE PIEDMONT
BY 02-05Z. PLAN TO MAINTAIN MEASURABLE POPS AT 20 PERCENT THOUGH
EXPECT AREAS OF DRIZZLE TO DEVELOP BY LATE EVENING AND CONTINUE INTO
THE OVERNIGHT. MIN TEMPS MID-UPPER 50S. ANY FOG THAT DEVELOPS WILL
BE SPOTTY AS STEADY NE SFC WIND WILL KEEP AIR MASS MIXED.
&&
.SHORT TERM /THURSDAY AND THURSDAY NIGHT/...
AS OF 312 PM WEDNESDAY...
THURSDAY...CONSIDERABLE CLOUDINESS IN THE MORNING WILL GRADUALLY
BECOME MOSTLY SUNNY/PARTLY CLOUDY ACROSS THE REGION AS AS LOW LEVEL
HIGH PRESSURE DRIFTS SOUTHWEST INTO THE NORTHERN MID ATLANTIC. THE
CLOSER PROXIMITY OF THIS FEATURE TO OUR REGION PLUS ADVECTION OF
DRIER AIR WILL AID TO SLOWLY ERODE THE CLOUD COVER FROM THE EAST
LATE THU AM THROUGH THE AFTERNOON. THE WESTERN-SOUTHERN PIEDMONT
WILL BE THE LAST TO EXPERIENCE PARTIAL CLEARING. BASED ON THIS SKY
TREND...EXPECT WARMER TEMPS EAST VERSUS WEST. MAX TEMPS LOWER 70S
FAR SOUTH-SE TO UPPER 60S W-NW.
THURSDAY NIGHT..RIDGE AT THE SURFACE AND ALOFT WILL RESULT IN FAIR
SKIES. RESIDUAL LOW LEVEL MOISTURE SHOULD ALLOW PATCHES OF FOG TO
DEVELOP. IF SFC WINDS ABLE TO DECOUPLE...MAY SEE WIDESPREAD FOG WITH
POCKETS OF DENSE FOG. COOLER OVERNIGHT TEMPS IN THE UPPER 40S TO THE
LOWER 50S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 250 PM WEDNESDAY...
FRIDAY THROUGH SUNDAY:
MEDIUM RANGE MODELS CONTINUE TO INDICATE AN AMPLIFIED PATTERN FOR
THE START OF THE PERIOD (LATE WEEK INTO THE WEEKEND)... WITH HIGH
PRESSURE ALOFT CENTERED JUST TO THE NORTH OF THE AREA AND SURFACE
HIGH PRESSURE LOCATED TO THE NORTHEAST OF THE REGION WITH CLOSED
LOWS FLANKING THE RIDGE ALOFT TO THE WEST AND EAST (ACROSS THE
CENTRAL CONUS AND WESTERN ATLANTIC). THIS WILL KEEP CENTRAL NC IN
THE CURRENT PATTERN OF A COOL EAST TO NORTHEASTERLY LOW LEVEL
FLOW... WITH PERIODS OF LOW CLOUDS AND POSSIBLE DRIZZLE. HOWEVER...
THINK WE WILL SEE AT LEAST SOME BREAKS IN THE CLOUDS OVER THE
WEEKEND. THUS... EXPECT HIGH TEMPS WILL GENERALLY BE BELOW NORMAL
RANGING FROM THE UPPER 60S TO THE 70S... WITH MORNING LOWS EXPECTED
TO BE NEAR NORMAL. THE COOLEST TEMPS ARE EXPECTED FRIDAY NIGHT INTO
SATURDAY WHEN IT APPEARS ANOTHER REINFORCING SURGE OF MOISTURE AND
COOLER TEMPS WILL FILTER INTO THE REGION... ASSOCIATED WITH ANOTHER
DISTURBANCE MOVING THROUGH THE CYCLONIC FLOW AROUND THE WESTERN
ATLANTIC LOW.
SUNDAY NIGHT THROUGH WEDNESDAY:
CONFIDENCE IN THE FORECAST PAST THE UPCOMING WEEKEND GOES DOWN
SIGNIFICANTLY... AS THE MEDIUM RANGE MODEL GUIDANCE IS STRUGGLING
WITH THE EVENTUAL PROGRESSION AND EVOLUTION OF THE CENTRAL CONUS
CLOSED LOW. HAVE STUCK CLOSE TO THE PREVIOUS FORECAST AND WPC AT
THIS TIME... WITH WPC GOING GENERALLY WITH THE 00Z/01ST ECENS MEAN
AS A SYNOPTIC GUIDE. WPC ALSO NOTED THE GFS/GEFS MEANS ARE
INCREASING OUTLIERS TO EVEN THE GEM GLOBAL AND UKMET (WHICH
YESTERDAY WERE MORE CORRELATED WITH THE GFS). NONETHELESS... IT
STILL LOOKS LIKE WE MAY SEE CHANCES FOR SHOWERS INCREASE NEXT WEEK
AS THE RIDGE BEGINS TO BREAK DOWN SOME/SHIFT MORE TO THE EAST OF THE
AREA. THUS... WILL ADVERTISE LOW END CHANCE POPS/SLIGHT CHANCE POPS
ACROSS THE AREA FOR EARLY NEXT WEEK... WITH SLOWLY MODERATING TEMPS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 140 PM WEDNESDAY...
A RELATIVELY MOIST NE FLOW OFF THE ATLANTIC WILL MAINTAIN A STRATUS
DECK WITH MVFR CEILINGS ACROSS MOST OF CENTRAL NC THIS AFTERNOON
THROUGH EARLY EVENING. THE EXCEPTION MAY BE IN VICINITY OF KFAY AND
KRWI WHERE THE CLOUD DECK MAY SCATTER INTO THE LOW END VFR FOR A FEW
HOURS LATE THIS AFTERNOON-EARLY EVENING. A STEADY NE WIND 9-14KTS
WITH GUSTS 17-22KTS WILL BE COMMON.
ANY CLEARING THAT OCCURS EARLY THIS EVENING WILL QUICKLY FILL IN
WITH LOW CLOUDS AND ASSOCIATED IFR/LOW END MVFR CEILINGS. MAY ALSO
SEE POCKETS OF MVFR VISIBILITY DUE TO FOG AND/OR DRIZZLE OVERNIGHT
INTO EARLY THU...MAINLY ACROSS THE PIEDMONT.
THURSDAY...LOW CLOUDS EARLY IN THE DAY MAY LIFT/DISSIPATE INTO A
FEW/SCATTERED STRATOCU DECK WITH BASES 2500-3500FT. MAINLY VFR
CONDITIONS EXPECTED THU EVENING THEN WIDESPREAD MVFR/IFR VISIBILITY
IN FOG IS ANTICIPATED.
FOR FRIDAY THROUGH MONDAY...HIGH PRESSURE OVER THE REGION SHOULD
PROVIDE PROLONGED PERIODS OF VFR CONDITIONS. EXCEPTIONS WILL BE
DURING THE LATE NIGHT/EARLY MORNING HOURS WHEN A 4-6 HOUR PERIOD OF
MVFR/IFR CEILINGS AND FOG ARE PROBABLE.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...WSS
NEAR TERM...WSS
SHORT TERM...WSS
LONG TERM...BSD
AVIATION...WSS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
250 PM EDT WED MAY 1 2013
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE CAROLINAS FROM THE NORTH WILL KEEP
PLEASANT BUT COOL WEATHER IN PLACE MUCH OF THE WEEK INTO THE
WEEKEND. A COLD FRONT MAY APPROACH THE REGION WITH MORE UNSETTLED
WEATHER EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 2:10 PM WEDNESDAY...LATEST RADAR AND SATELLITE LOOPS AND
SURFACE OBS REVEAL THAT AN EXTENSIVE LAYER OF STRATO-CU CONTINUES
TO BLANKET THE AREA AS SOME LIGHT SHOWERS OR PATCHES OF DRIZZLE
APPROACH THE CAPE FEAR REGION FROM JUST OFFSHORE. THE BIGGER
PICTURE HAS A STRONG SURFACE RIDGE EXTENDING SW ALONG THE
APPALACHIANS AS A SURFACE TROUGH EXTENDS JUST OFFSHORE.
EXTENSIVE CLOUDINESS WILL CONTINUE THROUGH THE NEAR TERM AS A
RELATIVELY COOL AND MOIST EASTERLY LOW LEVEL FLOW CONTINUES ACROSS
THE FORECAST AREA. MODEST COLD ADVECTION AND EXTENSIVE CLOUD COVER
WILL KEEP AFTERNOON TEMPERATURES GENERALLY BELOW NORMAL...ALTHOUGH
ANY BREAKS IN THE CLOUD COVER COULD ALLOW TEMPERATURES TO SPIKE
INTO THE MID 70S. OTHERWISE...MOST PLACES WILL SEE UPPER 60S TO
AROUND 70 FOR THE REMAINDER OF THE AFTERNOON.
CHANCES FOR PRECIPITATION WILL INCREASE MODESTLY THIS AFTERNOON
AND EVENING AS THE SURFACE TROUGH OVER THE COASTAL WATERS MOVES
ASHORE. P/W VALUES WILL PEAK AT OVER AN INCH TONIGHT AS MOISTURE
FLUX INCREASES. HAVE MADE NO SUBSTANTIAL CHANGES TO PRECIPITATION
CHANCES FOR THE REMAINDER OF THE NEAR TERM FROM THE PREVIOUS
FORECAST PACKAGES. STILL EXPECT ISOLATED SHOWERS THIS AFTERNOON
AND EVENING...WITH THE SLIGHT CHANCE FOR RAIN OVERNIGHT...AND QPF
VALUES ON THE ORDER OF A FEW HUNDREDTHS OF AN INCH.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE FORECAST AREA WILL CONTINUE TO BE ENTANGLED IN A
BLOCKING/OMEGA PATTERN ALOFT. MID LEVEL LOW PRESSURE/TROUGHS WILL BE
SITUATED ACROSS THE MISSISSIPPI VALLEY AND THE WESTERN ATLANTIC WITH
HIGH PRESSURE AXIS OVER THE UPPER GREAT LAKES REGION EXTENDING
SOUTH. AT THE SURFACE...HIGH PRESSURE WILL REMAIN ALIGNED JUST UNDER
THE UPPER RIDGE AXIS. LOW CLOUDS AND COOL TEMPERATURES WILL PREVAIL
THURSDAY WITH CONDITIONS A BIT DRIER FRIDAY. SOUNDINGS SHOW MOISTURE
DECREASES APPRECIABLY FRIDAY ALLOWING A BETTER CHANCE FOR DEEPER
MIXING. REGARDING TEMPERATURES...GUIDANCE IS IN GENERALLY GOOD
AGREEMENT WITH THE PERSISTENT LOW LEVEL FLOW KEEPING THE BOUNDARY
LAYER MIXED OVERNIGHT...AND IT IS THESE PERIODS WHERE I
DEVIATED...WARMER...AWAY FROM GUIDANCE.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...A RATHER MUDDLED FORECAST AS THE CAROLINAS
WILL BE UNDERNEATH THE RIDGE PORTION OF AN OMEGA BLOCK THAT MAY OR
MAY NOT BE CLOSING OFF. THAT IS...THE WESTERN CUTOFF WILL BE TRYING
TO PROGRESS EASTWARD UNDER THE RIDGE AND IMPINGE UPON THE REGION
FROM THE WEST. MODEL SOLUTIONS HAVE VARIED WILDLY AND THE BEST
COURSE OF ACTION AT THIS POINT SEEMS TO BE TO MINIMIZE CHANGES
ESPECIALLY SINCE PREVIOUS FORECAST ITERATIONS HAVE INCORPORATED
MODEL BIAS AND FAVORED CLIMATOLOGICALLY LIKELY PATTERN EVOLUTION.
THAT SAID...GUIDANCE SUCH AS THE GFS WHICH AGGRESSIVELY BRING THE
WESTERN CUTOFF INTO THE REGION BY EARLY NEXT WEEK APPEAR LEAST
LIKELY. THE EC SPLITS THE TROUGH AND HAS THE SOUTHERN FEATURE
CUTTING BENEATH THE RIDGE NOW ALBEIT IN A MUCH WEAKENED STATE AND
ALSO WELL SUPPRESSED TO THE SOUTH BY THE STALWART RIDGE...SO MUCH SO
THAT IT MAY BE HARD PRESSED TO GENERATE WEATHER LOCALLY SAVE FOR
PERHAPS FAR SRN ZONES. MEANWHILE THE REMAINING ENERGY IS FORCED TO
RIDE UP OVER THE RIDGE AND GETS SHUNTED INTO CANADA. DOWNSTREAM FROM
ALL OF THIS ACTION WILL BE THE WEST ATLANTIC RIDGE...THE DEGREE OF
ITS AMPLIFICATION AFFECTED BY ALL ALREADY DISCUSSED. SINCE THIS WILL
BE THE FEATURE AIDING IN PUSHING HIGHER PRESSURES/SLIGHTLY COOLER
AIR INTO THE CAROLINAS IT TOO WILL BE A PLAYER IN THE
FORECAST...MAINLY DICTATING HOW MUCH COOLER THAN CLIMO AFTERNOONS
END UP OVER THE WEEKEND. THE WEAKENING OF BOTH UPPER LOWS LATER IN
THE PERIOD SHOULD ALLOW TEMPS TO CREEP UP BACK TOWARDS CLIMO. RAIN
CHANCES ARGUABLY MAY INCREASE LATE IN THE PERIOD BUT OVERALL WILL
STILL REMAIN QUITE LOW.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...VISIBLE SATELLITE IMAGERY SHOWS AN EXTENSIVE STRATOCU
DECK ACROSS THE CWA...THOUGH CIGS AT MOST TERMS HAVE NOW LIFTED TO
VFR LEVELS. LOW CLOUDS WILL LIKELY PERSIST THRU THE PERIOD WITH HIGH
PRESSURE WEDGED INTO THE CAROLINAS. HAVE INCLUDED VCSH FOR KILM
BASED ON RADAR TRENDS AND LATEST HRRR OUTPUT. EXPECT VFR CIGS TO
BECOME MVFR AFTER 00Z WITH IFR STRATUS CERTAINLY POSSIBLE OVERNIGHT
AT ALL TERMS. NORTHEAST WINDS 10-12 KTS WILL WEAKEN SLIGHTLY TONIGHT
BEFORE PICKING BACK UP TO AROUND 10 KTS EARLY THURSDAY. DURING THE
DAY...EXPECT MVFR CIGS WITH E-NE WINDS 10 TO 15 KTS AND GUSTS OF
20-25 KTS.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS THURSDAY WITH BREEZY
CONDITIONS THROUGH FRIDAY. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2:10 PM WEDNESDAY...HIGH PRESSURE PRESSING DOWN FROM THE
NORTH WILL MAINTAIN A STEADY NORTHEASTERLY FLOW THOUGH THE NEAR
TERM...WITH WINDS INCREASING TO 15 TO 20 KTS THIS EVENING. SEAS
WILL BUILD INTO THE 4 TO 6 FT RANGE TONIGHT...SO KEEPING PRESENT
SMALL CRAFT ADVISORY IN PLACE FOR TONIGHT WITH NO SUBSTANTIAL
CHANGES.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...PERSISTENT NORTHEAST FLOW WILL BE THE STORY
THROUGH THE PERIOD. DIFFICULT TO ACTUALLY NAIL DOWN THE PERIOD WHERE
WINDS WILL BE THE HIGHEST OTHER THAN A GENERAL INCREASE LATE
FRIDAY/EARLY SATURDAY WHEN THE GRADIENT PICKS UP A BIT WITH LOW
PRESSURE DEVELOPING INTO THE TENNESSEE VALLEY. OVERALL EXPECT
HEALTHY 15-20 KNOTS. WAVEWATCH SEAS OF 3-7 FEET LOOK REASONABLE AND
THE SMALL CRAFT ADVISORY CONTINUES FOR ALL WATERS THURSDAY.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...ON SATURDAY THE COASTAL WATERS WILL SIT
BETWEEN TWO UPPER LEVEL CUTOFF TROUGHS WITH A RIDGE POKED UP BETWEEN
UP THE COASTLINE. THE EASTERN TROUGH WILL HELP DRIVE SURFACE HIGH
PRESSURE DOWN THE EASTERN THIRD OF THE U.S. BRINGING A
NORTHEASTERLY GRADIENT WIND LOCALLY. THE STRENGTH OF THE WIND AND
RESULTING WAVES PAIRED WITH LONG FETCH SWELL ENERGY COULD
NECESSITATE AND ADVISORY. HEADING INTO SUNDAY THE SURFACE FLOW MAY
VEER AND WEAKEN JUST ENOUGH TO DROP FLAGS DOWN TO CAUTIONARY
HEADLINES. ONE CAVEAT BEING THAT THE UPPER LEVEL PATTERN IS ONE THAT
IS OFTEN POORLY HANDLED BY GUIDANCE. SPECIFICALLY IT IS USUALLY
BROKEN DOWN FROM BEING BLOCKED TO PROGRESSIVE TOO QUICKLY. THAT SAID
ADVISORY MAY LAST A BIT LONGER THAN CURRENTLY IMPLIED BY FCST. WITH
A SIMILAR POSSIBILITY OF SLOWER PROGRESSION MONDAY WILL BRING
ADDITIONAL SLIGHT VEERING AND OF WINDS. GUIDANCE SHOWING JUST ENOUGH
SWELL TO PUSH SEAS BACK CLOSE TO SCA/SCEC THRESHOLDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EDT
THURSDAY FOR AMZ250-252-254-256.
&&
$$
SYNOPSIS...SHK
NEAR TERM...REK
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
210 PM EDT WED MAY 1 2013
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE CAROLINAS FROM THE NORTH WILL KEEP
PLEASANT BUT COOL WEATHER IN PLACE MUCH OF THE WEEK INTO THE
WEEKEND. A COLD FRONT MAY APPROACH THE REGION WITH MORE UNSETTLED
WEATHER EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 2:10 PM WEDNESDAY...LATEST RADAR AND SATELLITE LOOPS AND
SURFACE OBS REVEAL THAT AN EXTENSIVE LAYER OF STRATO-CU CONTINUES
TO BLANKET THE AREA AS SOME LIGHT SHOWERS OR PATCHES OF DRIZZLE
APPROACH THE CAPE FEAR REGION FROM JUST OFFSHORE. THE BIGGER
PICTURE HAS A STRONG SURFACE RIDGE EXTENDING SW ALONG THE
APPALACHIANS AS A SURFACE TROUGH EXTENDS JUST OFFSHORE.
EXTENSIVE CLOUDINESS WILL CONTINUE THROUGH THE NEAR TERM AS A
RELATIVELY COOL AND MOIST EASTERLY LOW LEVEL FLOW CONTINUES ACROSS
THE FORECAST AREA. MODEST COLD ADVECTION AND EXTENSIVE CLOUD COVER
WILL KEEP AFTERNOON TEMPERATURES GENERALLY BELOW NORMAL...ALTHOUGH
ANY BREAKS IN THE CLOUD COVER COULD ALLOW TEMPERATURES TO SPIKE
INTO THE MID 70S. OTHERWISE...MOST PLACES WILL SEE UPPER 60S TO
AROUND 70 FOR THE REMAINDER OF THE AFTERNOON.
CHANCES FOR PRECIPITATION WILL INCREASE MODESTLY THIS AFTERNOON
AND EVENING AS THE SURFACE TROUGH OVER THE COASTAL WATERS MOVES
ASHORE. P/W VALUES WILL PEAK AT OVER AN INCH TONIGHT AS MOISTURE
FLUX INCREASES. HAVE MADE NO SUBSTANTIAL CHANGES TO PRECIPITATION
CHANCES FOR THE REMAINDER OF THE NEAR TERM FROM THE PREVIOUS
FORECAST PACKAGES. STILL EXPECT ISOLATED SHOWERS THIS AFTERNOON
AND EVENING...WITH THE SLIGHT CHANCE FOR RAIN OVERNIGHT...AND QPF
VALUES ON THE ORDER OF A FEW HUNDREDTHS OF AN INCH.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...HIGHLY AMPLIFIED PATTERN DEVELOPS DURING
THE END OF THE WEEK AS ANOMALOUSLY STRONG 5H RIDGE TRANSITIONS INTO
AN OMEGA-BLOCK TYPE PATTERN INTO FRIDAY. THIS RIDGE IS SANDWICHED
BETWEEN TWO STRONG CLOSED LOWS...ONE ACROSS THE WESTERN
ATLANTIC...AND ONE STALLED OVER THE GREAT PLAINS. A
THIRD...WEAKER...AREA OF LOW PRESSURE IS SQUELCHED SOUTHWARD THROUGH
THE GULF OF MEXICO.
TROUGH OF LOW PRESSURE OFFSHORE THURSDAY WILL GET SHUNTED WELL SOUTH
BY RIDGE ADVANCING FROM THE NE. WHILE ISOLATED SHOWERS WILL REMAIN
POSSIBLE THROUGH THURSDAY WITH DIURNAL HEATING IN A MODESTLY MOIST
ENVIRONMENT AND ONSHORE FLOW...TREND WILL BE FOR A DRYING COLUMN AND
HENCE DECREASING RAIN CHANCES BY THURSDAY NIGHT. AS HIGH MORE
STRONGLY RIDGES DOWN THE COAST ON FRIDAY...COMBINED WITH DEVELOPING
OMEGA BLOCK ALONG THE EASTERN CONUS...FRIDAY WILL BE A DRY DAY WITH
AMPLE SUNSHINE.
EVEN WITH A RIDGE BUILDING ALOFT...COOL NE FLOW WILL KEEP TEMPS
SOMEWHAT BELOW NORMAL FOR EARLY MAY...IN THE LOW 70S MOST SPOTS BOTH
DAYS. WHILE RADIATIONAL COOLING WILL BE MINIMIZED OVERALL BY NE
WINDS...COOL ADVECTION WILL HELP LOWS FALL TO A FEW DEGREES BELOW
NORMAL AS WELL...LOW 50S INLAND...MID 50S AT THE COAST.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AS OF 300 AM WEDNESDAY...STILL MUCH UNCERTAINTY IN THE EXTENDED AS
LONG-RANGE GUIDANCE REFUSES TO COOPERATE WITH ONE-ANOTHER. OMEGA
BLOCK IN PLACE AT THE START OF THE PERIOD WILL FUNCTION AS A DAM TO
THE ATMOSPHERIC RIVER...LIMITING ANY SIGNIFICANT CHANGES TO THE
SENSIBLE WEATHER. WITH LARGE RIDGE ALOFT AND SURFACE HIGH RIDGING
DOWN THE COAST...EXPECT QUITE A BIT OF SUNSHINE...BUT NE WINDS WILL
KEEP TEMPS A LITTLE BELOW CLIMO EACH AFTN THROUGH THE WKND. GFS
CONTINUES TO BE MORE AGGRESSIVE BREAKING DOWN THE RIDGE...A KNOWN
BIAS OF THE GUIDANCE...AND WILL FAVOR THE MORE-CONSISTENT ECMWF AND
LOWER POP TO SILENT FOR THE WKND.
MAJOR DIFFERENCES EXIST EARLY WEEK WITH THE BEHAVIOR OF A CLOSED LOW
ACROSS THE GREAT PLAINS AND THE EVOLUTION OF THE OMEGA BLOCK.
ECMWF/CMC/MANY-ENSEMBLES SUPPORT THE CLOSED LOW MOVING WELL NORTH
OVER TOP THE RIDGE THROUGH TUESDAY...WHILE THE GFS SUGGESTS THE LOW
WILL BREAK DOWN THE RIDGE AND MOVE BASICALLY OVERHEAD...AND BY EARLY
NEXT WEEK THE MODELS ARE 180 DEGREES OUT OF PHASE. THE GFS SOLUTION
SEEMS UNLIKELY...AND THUS WILL SHOW A WARMING TREND INTO EARLY NEXT
WEEK. WILL CONTINUE WITH INHERITED SCHC/SILENT POP FOR NEXT WEEK TO
ACCOUNT FOR THE GFS...BUT IT CERTAINLY SEEMS PLAUSIBLE THAT THE
ENTIRETY OF THE EXTENDED WILL BE RAIN-FREE WITH COOL-TO-PLEASANT
MID-SPRING WEATHER.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AS OF 18Z...VISIBLE SATELLITE IMAGERY SHOWS AN EXTENSIVE STRATOCU
DECK ACROSS THE CWA...THOUGH CIGS AT MOST TERMS HAVE NOW LIFTED TO
VFR LEVELS. LOW CLOUDS WILL LIKELY PERSIST THRU THE PERIOD WITH HIGH
PRESSURE WEDGED INTO THE CAROLINAS. HAVE INCLUDED VCSH FOR KILM
BASED ON RADAR TRENDS AND LATEST HRRR OUTPUT. EXPECT VFR CIGS TO
BECOME MVFR AFTER 00Z WITH IFR STRATUS CERTAINLY POSSIBLE OVERNIGHT
AT ALL TERMS. NORTHEAST WINDS 10-12 KTS WILL WEAKEN SLIGHTLY TONIGHT
BEFORE PICKING BACK UP TO AROUND 10 KTS EARLY THURSDAY. DURING THE
DAY...EXPECT MVFR CIGS WITH E-NE WINDS 10 TO 15 KTS AND GUSTS OF
20-25 KTS.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS THURSDAY WITH BREEZY
CONDITIONS THROUGH FRIDAY. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 2:10 PM WEDNESDAY...HIGH PRESSURE PRESSING DOWN FROM THE
NORTH WILL MAINTAIN A STEADY NORTHEASTERLY FLOW THOUGH THE NEAR
TERM...WITH WINDS INCREASING TO 15 TO 20 KTS THIS EVENING. SEAS
WILL BUILD INTO THE 4 TO 6 FT RANGE TONIGHT...SO KEEPING PRESENT
SMALL CRAFT ADVISORY IN PLACE FOR TONIGHT WITH NO SUBSTANTIAL
CHANGES.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3:00 AM WEDNESDAY...HIGH PRESSURE RIDGING DOWN THE EAST
COAST WILL CREATE GUSTY NE WINDS THROUGH THE SHORT TERM...AND A
LONG DURATION SCA...WHICH IS IN EFFECT FOR THURSDAY ATTM...WILL
LIKELY BE NEEDED FOR THE ENTIRETY OF THE PERIOD. WINDS OF 15-25
KTS WILL BE PERSISTENT THROUGH THE END OF THE WEEK...FORCING WIND-
DRIVEN WAVES TO 4-7 FT EACH DAY. THE SEA SPECTRUM WILL BE
COMPRISED OF A NE WIND CHOP AND AN INCREASING-PERIOD NE SWELL DUE
TO THE LONG NE FETCH.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 6:18 AM WEDNESDAY...STATIC PATTERN FOR THE EXTENDED AS HIGH
PRESSURE CONTINUES TO PUSH DOWN THE COAST...PINCHING THE PRESSURE
GRADIENT ACROSS THE WATERS AND CREATING GUSTY NE WINDS THROUGH THE
WKND...ALTHOUGH SOME RELAXING IS LIKELY LATE. WINDS FROM THE NE
WILL BE 15-20 KTS SATURDAY AND INTO SUNDAY...BEFORE SLOWLY EASING
LATE AS RIDGE BREAKS DOWN SLIGHTLY WITH A WEAKENING GRADIENT.
THESE WINDS WILL HELP DRIVE SEAS TO 4-6 FT SATURDAY WHEN AN SCA
WILL LIKELY BE NEEDED...BEFORE FALLING SLOWLY SUNDAY TO 3-5 FT.
SEA SPECTRUM WILL CONSIST OF NE WIND WAVE AND A DECAYING NE SWELL.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EDT
THURSDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...REK
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...BJR
MARINE...REK/JDW
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
739 PM EDT THU MAY 2 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH THE WEEKEND THEN
WEAKEN SOME EARLY NEXT WEEK. LOW PRESSURE EXTENDING UP THE
MISSISSIPPI VALLEY TO LAKE MICHIGAN WILL STAY STATIONARY INTO
SATURDAY THEN SLOWLY MOVE EAST THROUGH THE LOWER TENNESSEE VALLEY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LITTLE CHANGE TO CURRENT FORECAST AT THIS TIME. LATEST HRRR MODEL
INDICATES A BIT OF CONVECTION DEVELOPING LATER TONIGHT OVER THE
EXTREME WEST. HOWEVER...WITH AIR MASS OVER THE REGION BEING SO
DRY...WE MAY JUST ESCAPE WITH A FEW SPRINKLES. OTHERWISE...THE
REST OF THE FORECAST AREA WILL REMAIN DRY AND QUITE PLEASANT TONIGHT.
LAKE BREEZE DROPPED TEMPERATURES INTO THE UPPER 50S ALONG THE
IMMEDIATE LAKESHORE AND LOWER TO MIDDLE 60S A BIT FURTHER INLAND.
EXPECTING LAND BREEZE TO DEVELOP AND BRING AND END TO THE COOLER
TEMPERATURES. WE SHOULD SEE A RISE IN THE TEMPERATURES THIS
EVENING BEFORE FALLING OFF AGAIN. TEMPERATURES ACROSS THE REST OF
THE AREA WILL SEE A GRADUAL DECLINE AFTER SUNSET.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY NIGHT/...
UPPER LEVEL TROUGH CLOSES OFF OVER THE SOUTHERN PLAINS ON FRIDAY
THEN SLOWLY DRIFTS EASTWARD OVER THE WEEKEND. HIGH CLOUD WILL
CONTINUE TO SPREAD NORTH AROUND THE UPPER LOW AND EXPECT PERIODS OF
SUN AND CLOUD OVER THE NEXT COUPLE DAYS. LOW LEVEL FLOW MAINTAINS AN
EASTERLY WIND COMPONENT BETWEEN HIGH PRESSURE OVER NEW ENGLAND AND
THE LOW TO THE SOUTH. THIS WILL CAUSE LOW LEVELS TO ACTUALLY UNDERGO
SOME DRYING BY SATURDAY AND 12Z MODELS MAINTAIN A DRY FORECAST
THROUGH THE WEEKEND. MODELS HAVE STRUGGLED WITH THE TRACK OF THE LOW
OVER THE LAST COUPLE DAYS BUT HAVE COME INTO FAIRLY GOOD AGREEMENT.
TEMPERATURES ON FRIDAY WILL BE SIMILAR TO TODAY THEN SETTLE BACK
DOWN INTO THE LOWER 70S AS THE AIRMASS COOLS OVER THE WEEKEND.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
IT APPEARS THAT MOST IF NOT ALL OF THE LONG TERM PERIOD WILL BE
DRY. THERE COULD BE A FEW SHOWERS IN THE SOUTH MONDAY AND TUESDAY
AS THE UPPER LOW PASSES TO THE SOUTH OF THE REGION. CHANCES ARE
REALLY SMALL AND NO MORE THAN A HUNDREDTH OR TWO OF RAINFALL IS
EXPECTED EVEN IF SHOWERS DEVELOP. HIGH PRESSURE WILL RETURN
WEDNESDAY AND THURSDAY WITH DRY WEATHER EXPECTED. TEMPERATURES WILL
AVERAGE ABOUT 5 DEGREES ABOVE NORMAL DURING THE PERIOD WITH HIGHS
TUESDAY THROUGH THURSDAY REACHING THE 70S.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH FRIDAY. MOST LOCATIONS WILL
ONLY SEE VARIABLE AMOUNTS OF HIGH LEVEL CLOUD COVER. HOWEVER
MODELS ARE TRYING TO PRODUCE SOME MIDDLE LEVEL SHOWERS/SPRINKLES
THAT COULD MOVE ACROSS THE WESTERN TAF SITES AFTER 06Z. CONFIDENCE
IS LOW IN THIS OCCURRING. OTHERWISE EXPECT SE WINDS TO CONTINUE
OVERNIGHT WITH SOME GUSTS AROUND 20 KNOTS FOR MOST LOCATIONS BY
FRIDAY AFTERNOON.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE BY MONDAY.
&&
.MARINE...
A FAIRLY PERSISTENT PATTERN WILL CONTINUE OVER LAKE ERIE INTO THE
WEEKEND. THE RIDGE WILL REMAIN OVER THE REGION AS AN UPPER LEVEL
LOW REMAINS TO THE WEST. A SOUTHEAST FLOW WILL REMAIN OVER THE LAKE
WITH AN ONSHORE FLOW DEVELOPING IN THE AFTERNOON. THE MODELS SHOW
THE UPPER LEVEL LOW DRIFTING SOUTH OF THE OHIO VALLEY FOR THE
BEGINNING OF NEXT WEEK. THIS WILL ALLOW THE WINDS TO SHIFT MORE
FROM THE NORTHEAST AND EVENTUALLY NORTHERLY BY LATE NEXT WEEK. THE
FLOW SHOULD REMAIN FAIRLY LIGHT AND REMAIN 15 KNOTS OR LESS THROUGH
MOST OF THE PERIOD.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...KUBINA
AVIATION...MULLEN
MARINE...GARNET
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
947 AM EDT WED MAY 1 2013
.DISCUSSION...
12Z RAOBS FROM OHX...FFC...AND GSO SHOW AN INVERSION AROUND 750
MB...WHICH SHOULD HELP CAP CONVECTION TODAY IN MOST LOCATIONS. THE
LATEST RUC SOUNDINGS SHOW THIS INVERSION WEAKENING A BIT THIS
AFTERNOON ACROSS THE CUMBERLAND PLATEAU. IF ANY SHOWERS ARE ABLE TO
DEVELOP...THAT WOULD PROBABLY BE THE AREA IT WOULD OCCUR WITH THE
MIDLEVEL RIDGE AXIS TO OUR EAST. THE CURRENT FORECAST HAS A SLIGHT
CHANCE POP IN THE NORTHERN PLATEAU...AND THIS SEEMS REASONABLE.
FORECAST TEMPS LOOK A BIT COOL NORTH BASED ON THE LATEST OBS AND
GUIDANCE...AND LACK OF CLOUD COVER SO FAR. TRI SHOULD BE AT LEAST
AS WARM AS YESTERDAY WHEN THE HIGH REACHED 80. WILL ISSUE AN UPDATE
FOR TEMPS IN THAT AREA.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1128 AM CDT WED MAY 1 2013
.UPDATE...
A STALLED FRONTAL BOUNDARY EXTENDS FROM ROUGHLY FROM SHEBOYGAN
THROUGH MADISON THROUGH MONROE LATE THIS MORNING...MARKED BY
SOUTHERLY WINDS ON THE SOUTH SIDE AND NORTHERLY WINDS ON THE NORTH
SIDE. HRRR IS DOING A NICE JOB HANDING THE CURRENT LOCATION OF THE
FRONT...AND SHOWS THAT FRONT LIFTING NORTHWARD A BIT THIS AFTERNOON.
TEMPERATURES ARE WARMING QUICKLY SOUTH OF THE FRONT...AND WARMING
SLOWLY NORTH OF IT. RACINE HAS ALREADY HIT 82 AND MILWAUKEE WILL HIT
LOWER 80S AS WELL. THERE IS A LOT MORE UNCERTAINTY FOR HIGH TEMPS IN
MADISON... WITH THE FRONT WAFFLING AROUND RIGHT OVER THE CITY TODAY.
THERE IS A WEAK ENOUGH PRESSURE GRADIENT OVER SOUTHEAST WISCONSIN TO
ALLOW A LAKE BREEZE TO DEVELOP. TIMING OF THIS LAKE BREEZE IS VERY
UNCERTAIN...BUT SOUTHEAST WINDS COULD DEVELOP AT MILWAUKEE AIRPORT
BY 1 PM TODAY AND MOVE INLAND TO KENOSHA BY MID AFTERNOON. SCATTERED
CUMULUS CLOUDS COULD DEVELOP ALONG THE LAKE BREEZE THIS
AFTERNOON...BUT CLEAR SKIES ARE EXPECTED ELSEWHERE.
REMOVED ANY POPS NORTHWEST OF MADISON FOR TODAY. IT APPEARS THAT ANY
LIGHT RAIN DEVELOPING WELL BEHIND THE COLD FRONT WILL REMAIN
NORTHWEST OF THE MKX FORECAST AREA DURING THE DAY. EXPECT SOME RAIN
TO SPREAD INTO NORTHWEST AREAS OVERNIGHT...AND INTO PORTIONS OF
SOUTHEAST WI THURSDAY MORNING. CUT BACK ON POPS FOR THE EVENING AND
WILL CONTINUE TO EVALUATE PRECIP CHANCES THROUGH THU.
THE 13Z HRRR AND 12Z NAM AND REGIONAL CANADIAN MODELS ARE STILL
ADVERTISING THIS COLD FRONT CHARACTERIZED BY NNE GUSTY WINDS RACING
DOWN THE LAKE...SOMETIMES CALLED A PNEUMONIA FRONT...TO OCCUR EITHER
LATE AFTERNOON OR EARLY THIS EVENING. THERE IS STILL UNCERTAINTY
ABOUT WHETHER LOW CLOUDS WILL DEVELOP WITH THE FRONT OR NOT. THERE
ARE NO SIGNS OF LOW CLOUDS AT THIS TIME.
&&
.AVIATION/18Z TAFS/...
LAKE BREEZE WILL DEVELOP EARLY THIS AFTERNOON FROM MILWAUKEE AND
SOUTH...ALTHOUGH TIMING IS VERY UNCERTAIN. VFR CUMULUS CLOUDS COULD
DEVELOP ALONG THE LAKE BREEZE. ELSEHWERE...WINDS WILL BE NORTH TO
NORTHEAST ON THE NORTH SIDE OF A STALLED FRONT. WINDS WILL BE
SOUTHWEST TO SOUTH ON THE SOUTH SIDE OF THE FRONT. THE FRONT WILL BE
WAFFLING AROUND ACROSS THE CENTRAL PORTION OF SOUTHERN
WISCONSIN...INCLUDING MADISON...WATERTOWN AND WAUKESHA.
VFR CONDITIONS FOR MOST OF THE PERIOD...HOWEVER NEED TO WATCH FOR
POTENTIAL LOW CLOUDS FORMING NEAR LAKE MICHIGAN IN MOIST ONSHORE
FLOW TONIGHT AND SPREADING WESTWARD. CLOUDS WOULD BE IFR CAT.
&&
.PREV DISCUSSION... /ISSUED 326 AM CDT WED MAY 1 2013/
TODAY AND TONIGHT...FORECAST CONFIDENCE - VERY LOW.
KMKX WSR-88D CONTINUES TO SHOW SFC COOL FRONT SLIDING SOUTHEAST
ACROSS SOUTHERN WI. SFC OBS AND RADAR FINE LINE ESTIMATE BOUNDARY
ROUGHLY FROM VCNTY OF KSBM TO KEFT AT 08Z. SFC FRONT A LITTLE
FASTER THAN DEPICTED BY SHORT TERM GUIDANCE DUE TO 3 HOUR 4-6MB
PRESSURE RISES UPSTREAM OVER CENTRAL/NORTHERN WI. LOW LEVEL
FLOW APPEARS TO BE WEAKENING BEHIND FRONT SO WOULD NOT BE SURPRISED
TO SEE FRONT STALL FOR A TIME ACROSS SOUTHEAST WI. HOWEVER HIGH
PRESSURE BUILDING INTO THE PLAINS WILL ALSO BUILD INTO NORTHERN WI.
INCREASING UPSTREAM PRESSURE SHOULD EITHER GIVE NUDGE TO SFC FRONT
TO THE SOUTH...OR ELSE WILL RESULT IN PNEUMONIA-TYPE FRONT SLIDING
SOUTH DOWN LAKE MI TODAY...EVENTUALLY MELDING WITH SFC FRONT TO THE
WEST. THESE PNEUMONIA FRONTS HAVE FOUND TO BE MOST FREQUENT IN THE
MONTH OF MAY BEFORE LAKE MI WATER TEMPS BEGIN TO MODIFY.
EITHER WAY...NOT EXPECTING QUITE AS WARM A DAY ACROSS SOUTHERN
WI...WITH THE WARMEST TEMPERATURES IN THE FAR SOUTH CENTRAL INTO
PARTS OF THE SOUTHEAST...BEFORE WINDS TURN ONSHORE LATER THIS MRNG
OR EARLY AFTERNOON. HOWEVER TIMING IS CRITICAL. FOR NOW HAVE KMKE
RISING INTO THE MIDDLE TO UPPER 70S BEFORE WINDS TURN ONSHORE...BUT
COULD EASILY CRACK THE 80 MARK AGAIN IF WINDS DELAY TURNING
SEVERAL HOURS. A LARGE RANGE OF DAYTIME HIGH TEMPS ARE
EXPECTED...VARYING FROM THE MID TO UPPER 60S IN THE NORTHWEST TO THE
LOWER 80S SOUTHEAST.
MAIN FORCING ASSOCIATED WITH SLOPING FRONTOGENETICAL FORCING REMAINS
NORTHWEST OF AREA TODAY...AND WITH RH REMAINING LIMITED IN THE LOW
TO MID LEVELS...WL GO MOSTLY DRY...WITH A SMALL CHANCE IN THE AFTN
WEST OF KMSN.
LAYER Q-VECTOR CONVERGENCE AXIS BEGINS TO SLIDE EWD ACROSS SOUTHERN
WI TONIGHT AS LOW LEVEL MOISTURE GRADUALLY INCREASES. UPPER LEVEL
TROF OVER PLAINS BEGINS TO SHARPEN AND CAUSE FLOW TO PIVOT
NORTHWEST...WHILE LOW LEVEL FLOW INFLUENCED BY INCREASING ELY FLOW.
INCREASING LOW LEVEL JET RESULTS IN WEAK WAA AND SAID Q-VECTOR
CONVERGENCE TONIGHT...SO WL SPREAD SMALL POPS ACROSS ENTIRE AREA.
ELEVATED CAPE APPROACHES 1000 J/KG SO KEPT SMALL THUNDER THREAT IN
AS WELL.
THURSDAY THROUGH SUNDAY...FORECAST CONFIDENCE...LOW TO MEDIUM
THE STORY FOR LATE THIS WEEK INTO THE WEEKEND CONTINUES TO BE THE
LARGE UPPER LOW THAT WILL MEANDER THROUGH THE REGION. AS IS OFTEN
THE CASE WITH CUTOFF LOWS...MODELS CONTINUE TO STRUGGLE WITH THE
TRACK OF THIS LOW. BY SUNDAY EVENING...THE GFS AND CANADIAN HAVE THE
LOW CENTERED OVER MISSOURI...WITH THE ECMWF PUTTING IT ALONG
THE MINNESOTA/CANADA BORDER. AS A RESULT...STILL A GOOD AMOUNT
VARIANCE AMONG MODELS IN TIMING OF PRECIP CHANCES AND TEMPS
THROUGH THE WEEKEND. GENERALLY CONTINUED THE TREND OF GOING DOWN
THE MIDDLE OF THE ROAD FOR NOW. EITHER WAY...LOOKS COOLER AND WET
THROUGH THIS PERIOD.
MONDAY AND TUESDAY...FORECAST CONFIDENCE...LOW TO MEDIUM
UPPER LOW WILL FINALLY BE OUT OF THE AREA BY MONDAY...WITH A
SHORTWAVE TO IMPACT THE STATE EITHER MONDAY NIGHT OR TUESDAY
NIGHT...DEPENDING ON THE MODEL. KEPT SOME POPS THROUGH EARLY WEEK
DUE TO THE UNCERTAINTY IN TIMING. SPLIT THE DIFFERENCE IN MODEL
TEMPS...RESULTING IN NEAR NORMAL VALUES FOR EARLY MAY.
AVIATION/12Z TAFS/...VFR CONDITIONS FOR MOST OF THE
PERIOD...HOWEVER NEED TO WATCH FOR POTENTIAL LOW CLOUDS FORMING NEAR
LAKE MICHIGAN IN MOIST ONSHORE FLOW TONIGHT AND SPREADING WESTWARD.
CLOUDS WOULD BE IFR CAT. SMALL THREAT FOR -SHRA...MAINLY TNGT.
MARINE...EXPECT BUILDING SFC PRESSURE TO THE NORTH TO EITHER
CONTINUE TO NUDGE SURFACE COOL FRONT OVER SOUTH CENTRAL WI FURTHER
SOUTHEAST...OR ELSE EXPECT PNEUMONIA-TYPE FRONT TO SLIDE SOUTH
ACROSS NEARSHORE WATERS DURING THE DAY...TURNING WINDS TO THE EAST
OR NORTHEAST. WINDS AND WAVES MAY GET CLOSE TO SMALL CRAFT ADVISORY
LEVELS LATE TODAY AND TONIGHT...BUT TOO MUCH UNCERTAINTY IN TIMING
AND STRENGTH AT THIS TIME TO ISSUE HEADLINE. NEARSHORE WATER HAS
WARMED /FOR NOW/ INTO THE LOW TO MID 50S PER SGNW3 SO THREAT FOR FOG
IN THE NEARSHORE THIS MRNG APPEARS LOW. BETTER CHANCE TOWARD
MID-LAKE WHERE LAKE WATER TEMPS REMAIN AROUND 40 PER BUOY 45007.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...MBK
THURSDAY THROUGH TUESDAY...DDV
AREA FORECAST DISCUSSION
NWS PUEBLO CO
321 AM MDT FRI MAY 3 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM MDT FRI MAY 3 2013
CURRENTLY...CLEAR SKIES WITH NORTHERLY FLOW ALOFT AS THE UPPER
TROUGH SITS TO THE EAST OF COLORADO OVER KS AND NE...AS PER LATEST
SATELLITE IMAGERY AND H5 RAP ANALYSIS. WIDESPREAD BELOW FREEZING
TEMPS FOR THE EASTERN CO PLAINS AS OF 3 AM.
TODAY AND TONIGHT...NOT A LOT TO ADD TO THE ONGOING FORECAST PACKAGE
IN THE SHORT TERM. THE UPPER TROUGH TO THE EAST IS EXPECTED TO
STRENGTHEN AS IT EJECTS TO THE SE AWAY FROM CO...RELAXING THE WINDS
ALOFT FOR THE STATE. SUNNY TO MOSTLY SUNNY SKIES ARE EXPECTED
TODAY...WITH A NICE REBOUND FOR TEMPS INTO THE UPPER 50S TO MID 60S
FOR MOST LOCATIONS TODAY. LIGHT WINDS AND CLEAR SKIES TONIGHT WILL
PRODUCE ONE MORE NIGHT AND SUB-FREEZING TEMPS...AND CURRENT FREEZE
WATCH LOOKS GOOD. DECIDED TO HOLD OFF ON UPGRADING AT THIS
TIME...AND TO AVOID CONFUSION OPTED TO LET CURRENT WARNING RUN THE
COURSE...THEN AT EXPIRATION THE WATCH CAN BE UPGRADED. MOORE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM MDT FRI MAY 3 2013
...WETTER PATTERN POSSIBLE THIS PERIOD...
SIMULATIONS IN RATHER GOOD AGREEMENT GIVEN THE RATHER WEAK FLOW
REGIME WHICH WILL BE OVER THE WESTERN PART OF THE CONUS THIS
PERIOD. AT THE BEGINNING OF THIS PD (SAT 12Z)...A WELL ESTABLISHED
CUTOFF LOW WILL BE LOCATED IN THE VICINITY OF MISSOURI WHILE A
WEAKER CLOSED LOW WILL BE DEVELOPING OVER THE S IDAHO REGION. WEAK
RIDGING AND OVERALL WEAK MIDLVL FLOW WILL BE OVER THE FCST AREA.
AS THE WEEKEND PROGRESSES...THE LOW OVER MISSOURI WILL SLOWLY MOVE
EAST WHILE THE UPPER LOW OVER IDAHO RETROGRADES OVER N CALIF. THIS
WILL ALLOW FOR A SMALL MIDLVL RIDGE TO BUILD OVER THE FCST AREA.
GIVEN THIS PATTERN...I EXPECT IT WILL BE MAINLY DRY OVER THE
REGION. A FEW SCTD AFTERNOON AND EVENING TSRA WILL BE POSSIBLE
OVER THE CONTDVD AND AN ISOLATED STORM OR TWO WILL BE POSSIBLE
OVER THE S MTNS/PIKES PEAK REGION. DAYTIME TEMPS WILL BE PLEASANT
WITH MAINLY 60S ACROSS THE PLAINS AND VALLEYS.
DURING THE MONDAY TIMEFRAME...A SHORTWAVE WILL EJECT OUT OF THE
CALIF LOW AND MOVE ACROSS THE REGION. I EXPECT WE WILL SEE
INCREASING CHANCES OF SHOWER OVER THE MTNS WITH ISOLATED SHOWERS
BECOMING POSSIBLE OVER THE PLAINS LATE IN THE DAY. MAX TEMPS MONDAY
WILL BE A FEW DEGREES WARMER THAN THE WEEKENDS HIGHS. SHEAR WILL BE
INCREASING MONDAY (ALTHOUGH NOT ALL THAT STRONG)...SO WE MAY SEE A
BIT MORE ORGANIZED CONVECTION ON THIS DAY ON THE PLAINS.
TUESDAY...CALIF LOW STARTS TO MOVE EAST AND SIMULATIONS HINT AT A
DRY SLOT AFFECTING THE S TIER OF THE CWA. THIS SHOULD BRING A
DECREASING THREAT OF SHOWERS TO THE REGION AND ALLOW FOR TEMPS TO
RISE INTO THE MID 70S ACROSS THE PLAINS WITH 60S VALLEYS.
WEDNESDAY IS WHEN THE MAIN LOW MOVES OVER THE STATE...AND THIS IS
THE DAY WE SHOULD SEE THE MOST ACTIVE WX. THERE IS NOT MUCH COLD AIR
WITH THIS SYSTEM SO ALL PRECIP (EXCEPT OVER THE HIGHEST TRRN) SHOULD
BE LIQUID. SHEAR IS FCST TO BE RATHER IMPRESSIVE (ESPECIALLY GFS) OVER
THE FAR E PLAINS AND IT IS POSSIBLE WE MAY SEE OUR FIRST SEVERE WX
THREAT OVER THE FCST AREA. THERE WILL ALSO BE A GOOD CHANCE OF
PRECIP OVER THE ENTIRE AREA GIVEN THE EXPECTED INSTABILITY AND
FORCING. FOR NOW I HAVE POPS IN THE 20-40% RANGE...BUT THESE VALUES
MAY NEED TO BE INCREASED IF MODELS CONTINUE TO SHOW THIS SCENARIO.
MAX TEMPS THIS DAY WILL BE COOLER GIVEN THE LIKELY INCREASED CLOUD
COVER OVER THE FCST AREA.
WED NITE THROUGH THU THE WEAK UPPER LOW MOVES VERY LITTLE AND WE
SHOULD SEE A CONTINUED THREAT OF MUCH NEED PRECIP OVER THE FCST
AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 300 AM MDT FRI MAY 3 2013
VFR CONDITIONS ARE FORECAST FOR THE THREE MAIN TAF SITES OF
KCOS...KPUB AND KALS FOR THE NEXT 24 HRS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
COZ084>089-093>099.
FREEZE WARNING UNTIL 9 AM MDT THIS MORNING FOR COZ083>089-
093>099.
&&
$$
SHORT TERM...MOORE
LONG TERM...HODANISH
AVIATION...MOORE
AREA FORECAST DISCUSSION...UPDATED
NWS MIAMI FL
234 AM EDT FRI MAY 3 2013
.AVIATION...
PATCHY TO DENSE FOG HAS DEVELOPED OVER THE INTERIOR AREAS OF SOUTH
FLORIDA THIS MORNING. THE FOG COULD MOVE INTO THE TAF SITES OF
KTMB...KAPF...KFXE...AND KMIA BETWEEN 09Z AND 12Z THIS MORNING. SO
HAVE LOWER THE VIS AND CEILING INTO THE MVFR CONDITIONS FOR THE
FOG. REST OF THE TAF SITES SHOULD REMAIN IN THE VFR CONDITIONS
THROUGH THE EARLY MORNING HOURS OF TODAY. HOWEVER...KPBI TAF SITE
COULD SEE SOME SHOWERS THROUGH THE EARLY MORNING HOURS OF TODAY.
SO HAVE PUT IN VCSH FOR THIS SITE.
THE WINDS WILL BE MAINLY FROM THE WEST DIRECTION AT SPEEDS OF 5
KNOTS OR LESS AT THE EAST COAST TAF SITES THROUGH THIS
MORNING...EXCEPT KPBI WHERE THE WINDS WILL BE SWINGING FROM A
NORTHEAST DIRECTION TO A NORTHWEST DIRECTION AT 5 MPH OR LESS AND
AT KAPF WHERE THE WINDS WILL BE LIGHT AND VARIABLE.
ALL OF THE TAF SITES SHOULD SEE SHOWERS BETWEEN 11Z AND 17Z BEFORE
A CHANCE OF THUNDERSTORMS RETURN BETWEEN 17Z AND 00Z. SO HAVE PUT
IN VCSH FOR ALL OF THE TAF SITES FOR THE MORNING HOURS AND VCTS
FOR THE AFTERNOON HOURS FOR TODAY. THE WINDS WILL ALSO REMAIN IN A
WESTERLY DIRECTION FOR THE DAY HOURS TODAY AROUND 10 KNOTS. AT
THIS TIME WILL LEAVE THE CEILING AND VIS IN THE VFR CONDITIONS FOR
THE DAY HOURS TODAY...DUE TO THE UNCERTAIN TIMING OF THE SHOWERS
AND THUNDERSTORMS AFFECTING THE TAF SITES.
&&
.AVIATION...54/BNB
.PREV DISCUSSION... /ISSUED 959 PM EDT THU MAY 2 2013/
UPDATE...
A CLEARING TREND CONTINUES ACROSS THE REGION WITH HEAVY SHOWERS
AND THUNDERSTORMS EXITING THE LOCAL ATLANTIC WATERS TO THE EAST.
HOWEVER...THERE IS STILL A STILL A CHANCE OF ADDITIONAL SHOWERS AND
ISOLATED THUNDERSTORMS OVERNIGHT. THE OOZ SOUNDING INDICATED STEEP
LOW LEVEL LAPSE RATES AND THERE IS A SURFACE TROUGH DEVELOPING IN
THE EASTERN GULF WITH DEEPER LAYERED TROPICAL MOISTURE STILL
LINGERING ACROSS THE REGION. SOME OF THE MESOSCALE MODEL GUIDANCE
ALSO INDICATED POSSIBLE CONVECTION RETURNING TO THE ATLANTIC
WATERS AND PORTIONS OF EASTERN SOUTH FLORIDA TONIGHT.
&&
60
PREV DISCUSSION... /ISSUED 747 PM EDT THU MAY 2 2013/
AVIATION...
BULK OF PRECIPITATION HAS MOVED OFFSHORE IN ASSOCIATION WITH
MESOSCALE LOW PRESSURE AREA, OR MESOLOW, WHICH MOVED ACROSS SOUTH
FLORIDA THIS AFTERNOON. LEFTOVER MID/HIGH CLOUDS WILL MOVE THROUGH
THE AREA BY 04Z WITH ONLY SCT CLOUDS AND VFR CONDITIONS OVERNIGHT.
THE MESOLOW IS OFF THE SE FLORIDA COAST AS OF 00Z AND IS LIKELY
CAUSING A TEMPORARY INCREASE IN NE WINDS TO 20-30 KNOTS ALONG THE
EAST COAST. THESE WINDS SHOULD DECREASE LATER THIS EVENING AS THE
LOW MOVES FARTHER OFFSHORE AND THE LARGE SCALE GRADIENT FLOW TAKES
OVER. WINDS SHIFT TO SW ACROSS ALL OF SOUTH FLORIDA ON FRIDAY AS
MAIN SFC LOW MOVES ACROSS THE AREA. SCATTERED TSTMS WILL RETURN TO
THE AREA ON FRIDAY WITH VCTS INCLUDED AT ALL SITES. /MOLLEDA
&&
PREV DISCUSSION... /ISSUED 501 PM EDT THU MAY 2 2013/
UPDATE...
A SMALL CRAFT ADVISORY IS IN EFFECT FROM 2 AM THIS MORNING TO 200
PM FRIDAY FOR THE ATLANTIC WATERS TO THE EAST OF PALM BEACH COUNTY. THE
COMBINATION OF WINDS FORECAST TO INCREASE TO THE 16 TO 21 KNOT
RANGE AND A SMALL LONG PERIOD SWELL WILL RESULT IN SEAS TO NEAR 7
FEET MAINLY EXPECTED TO THE EAST OF PALM BEACH COUNTY.
60
PREV DISCUSSION... /ISSUED 324 PM EDT THU MAY 2 2013/
DISCUSSION...
WIDESPREAD SHOWERS AND THUNDERSTORMS HAVE MOVED ACROSS SOUTH
FLORIDA TODAY. A WELL DEVELOPED MCS/MCV WAS MOVING ACROSS SOUTH
FLORIDA THIS AFTERNOON...AND SOME STORMS HAVE SHOWN ROTATION.
THERE WERE REPORTS OF DAMAGE FROM A STORM IN BOCA RATON EARLIER
THIS AFTERNOON AS WELL. SEVERE STREET FLOODING WAS REPORTED IN THE
BOCA RATON AND DELRAY BEACH AREAS...WHERE OVER 7.5 INCHES OF RAIN
HAS FALLEN.
A SURFACE BOUNDARY APPEARED TO BE DRIFTING SOUTH AND IT WAS
LOCATED ACROSS BROWARD COUNTY THIS AFTERNOON...AND LOCALLY HEAVY
RAIN AND FLOODING WILL BE POSSIBLE ACROSS BROWARD AND MIAMI DADE
COUNTY THROUGH THIS EVENING. AN UPPER LEVEL LOW ACROSS THE
NORTHEASTERN GULF WILL CONTINUE TO SLIDE SOUTHEAST AND OPEN INTO A
TROUGH OVERNIGHT AS IT MOVES INTO THE FLORIDA PENINSULA. UPPER
LEVEL DIVERGENCE FROM THIS UPPER LOW MAY HELP STORMS CONTINUE INTO
THE EVENING BEFORE DIMINISHING. THE HRRR SHOWS SHOWERS
DISSIPATING AFTER 00Z THIS EVENING.
SURFACE LOW PRESSURE IS EXPECTED TO DEVELOP ACROSS THE EASTERN
GULF OF MEXICO AND MOVE OVER SOUTH FLORIDA ON FRIDAY. THIS
WILL ALLOW THE STEERING FLOW OVER SOUTH FLORIDA TO REMAIN LIGHT
FROM A SOUTH TO SOUTHWEST DIRECTION KEEPING THE DEEP TROPICAL
MOISTURE IN PLACE. SO SCATTERED TO NUMEROUS SHOWERS AND
THUNDERSTORMS ARE EXPECTED ACROSS THE REGION AGAIN ON FRIDAY. THE
EMPHASIS WILL BE FOR THE EAST COAST AND NORTHEAST COAST WHERE THE
BEST LOW LEVEL CONVERGENCE AND THE SURFACE BOUNDARY WILL BE
FOUND...ALONG WITH UPPER LEVEL FORCING ASSOCIATED WITH THE UPPER
LEVEL FLOW.
THE 500 MB TEMPS ON FRIDAY SHOULD BE A LITTLE BIT WARMER THAN
TODAY...DUE TO THE UPPER LEVEL LOW DISSIPATING OVER THE NORTHEAST
GULF OF MEXICO. HOWEVER...ANY STORMS THAT DO AFFECT SOUTH FLORIDA
TONIGHT INTO FRIDAY WILL BE CAPABLE OF PRODUCING HEAVY RAINFALL.
THE LOW WILL CONTINUE TO MOVE EAST OVER SOUTH FLORIDA ON SATURDAY
BEFORE MOVING INTO THE WESTERN ATLANTIC WATERS ON SUNDAY. SLIGHTLY
DRIER CONDITIONS ARE EXPECTED ON SATURDAY...BUT RAIN CHANCES WILL
CONTINUE FOR THE NORTHERN TWO-THIRDS OF THE REGION. MUCH DRIER
AIR WILL WORK INTO THE AREA FROM THE WEST ON SUNDAY.
FOR EARLY TO MIDDLE OF NEXT WEEK...A MID TO UPPER LEVEL LOW WILL
DEVELOP OVER THE TENNESSEE VALLEY AND MOVE SLOWLY EAST TOWARDS THE
MID ATLANTIC STATES. THIS WILL ALLOW FOR DRIER WEATHER TO CONTINUE
TO WORK INTO SOUTH FLORIDA FROM THE WEST. SO THE WEATHER SHOULD
REMAIN DRY OVER SOUTH FLORIDA FOR THE EARLY TO MIDDLE PART OF NEXT
WEEK.
AVIATION...
LIGHT TO MODERATE RAIN WILL CONTINUE AT KAPF AND KPBI THROUGH
ABOUT 21-22Z. VERY HEAVY RAIN AND THUNDERSTORMS WILL CONTINUE FOR
THE REST OF THE EAST COAST TAF SITES...WHERE IFR CONDITIONS MAY
OCCUR. RAIN IS EXPECTED TO BEGIN DIMINISHING AFTER 04-06Z
TONIGHT...WITH IMPROVING CONDITIONS. STORMS WILL BE POSSIBLE AGAIN
BEGINNING LATE MORNING ON FRIDAY. WINDS WILL BE VARIABLE THE REST
OF THIS AFTERNOON WITH GUSTY WINDS POSSIBLE. LIGHT AND VARIABLE
WINDS ARE EXPECTED AFTER MIDNIGHT. WITH LOW PRESSURE MOVING OVER
SOUTH FLORIDA...WESTERLY WINDS ARE EXPECTED ON FRIDAY.
MARINE...
THE WINDS OVER SOUTH FLORIDA TODAY INTO FRIDAY WILL BE FROM THE
SOUTH TO SOUTHEAST DIRECTION AT 10 KNOTS OR LESS...BEFORE SLOWLY
SWINGING TO A NORTHWEST DIRECTION BY LATE THIS WEEKEND AND
INCREASING SPEEDS TO 10 TO 15 KNOTS. AT THE SAME TIME...A SMALL
NORTHEAST SWELL OF 1 TO 3 FEET WILL CONTINUE TO AFFECT THE
ATLANTIC WATERS OF SOUTH FLORIDA LATE THIS WEEK INTO THIS
WEEKEND. THESE CONDITIONS WILL ALLOW FOR THE ATLANTIC SEAS TO
REMAIN BELOW 6 FEET TODAY INTO THIS WEEKEND...EXCEPT FOR THE PALM
BEACH WATERS WHERE THE SEAS COULD BUILD TO 6 FEET THIS WEEKEND.
FOR THE GULF SIDE...THE SEAS WILL REMAIN BELOW 6 FEET TODAY INTO
THIS WEEKEND. THE ONLY EXCEPTION IS THE OFFSHORE GULF WATERS WHERE
THE SEAS COULD BUILD TO 6 FEET BY THIS WEEKEND.
FIRE WEATHER...
DEEP TROPICAL MOISTURE WILL REMAIN OVER THE REGION ON FRIDAY WITH
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. SLIGHTLY DRIER
AIR WILL BEGIN TO MOVE INTO THE REGION ON SATURDAY...WITH LESSER
RAIN CHANCES.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 69 87 67 85 / 40 30 20 20
FORT LAUDERDALE 73 88 69 85 / 30 20 20 20
MIAMI 72 87 69 86 / 30 10 10 20
NAPLES 68 87 66 82 / 20 20 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...DENSE FOG ADVISORY UNTIL 9 AM EDT THIS MORNING FOR FAR SOUTH
MIAMI DADE-GLADES-HENDRY-INLAND BROWARD-INLAND COLLIER-
INLAND MIAMI DADE-INLAND PALM BEACH-MAINLAND MONROE.
AM...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 PM EDT THIS
AFTERNOON FOR COASTAL WATERS FROM JUPITER INLET TO
DEERFIELD BEACH, FL OUT 20 NM-WATERS FROM JUPITER INLET TO
DEERFIELD BEACH, FL EXTENDING FROM 20 NM TO 60 NM.
GM...NONE.
&&
$$
DISCUSSION/MARINE/FIRE...13/SI
AVIATION/RADAR...54/BNB
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
110 AM EDT FRI MAY 3 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 332 PM EDT THU MAY 2 2013
AN UPPER TROUGH OF LOW PRESSURE OVER THE GREAT PLAINS WILL DEEPEN
INTO A CLOSED UPPER LOW AND TRACK INTO THE MID MISSISSIPPI VALLEY BY
SATURDAY AND ACROSS TENNESSEE AND THE DEEP SOUTH SUNDAY AND MONDAY.
IT WILL MOVE OFF THE MID ATLANTIC COAST BY THE MIDDLE OF NEXT WEEK
AND HIGH PRESSURE WILL REBUILD ACROSS OUR REGION. THIS SYSTEM WILL
BRING INCREASING CHANCE OF SHOWERS NEXT FEW DAYS...ESPECIALLY WEST
AND SOUTH.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 1007 PM EDT THU MAY 2 2013
MAIN CHANGE OVER THE LAST SEVERAL UPDATES HAS BEEN TO TAILOR BACK
POPS...ESPECIALLY ACROSS THE WESTERN COUNTIES WHERE ONLY A FEW
ISOLATED THUNDERSTORMS ARE MOVING THROUGH. BELIEVE HRRR HAS THE
BEST HANDLE ON POPS TONIGHT INTO FRIDAY AND LEANED TOWARD THIS
GUIDANCE. AT THIS RATE BULK OF PRECIP WILL NOT REACH CENTRAL
INDIANA UNTIL AT LEAST LATE MORNING FRIDAY...IF NOT LATER.
PREVIOUS DISC FOLLOWS...
RADAR HAS SHOWN AND INCREASE TO SHOWERS AND THUNDERSTORMS ACROSS
ILLINOIS THIS AFTERNOON AS CAPES HAVE BEEN RUNNING FROM 1500 TO 2000
J/KG. SOME OF THESE MAY SPREAD INTO FAR WESTERN SECTIONS THIS
EVENING AS AIRMASS IS SOMEWHAT UNSTABLE THERE. FATHER EAST WILL
DOWNPLAY RAIN CHANCES SOME AS MODELS HAVE TENDED TO BE TOO QUICK IN
SPREADING RAIN EAST TOO MUCH. LAPS SHOWS CAPES FROM INDY AND
EASTWARD NO MORE THAN 200 J/KG AND SOME OF THE PREVIOUS MODELS
INDICATED THAT IT COULD BE RAINING MUCH OF TODAY HERE AS WELL.
FOR NOW WILL MENTION HIGH CHANCE POPS FAR WEST...AND SLIGHT CHANCES
FROM INDY AND WESTWARD LATER TONIGHT. WHILE MOST EASTERN AREAS
SHOULD REMAIN DRY. OVERNIGHT LOWS WILL BE IN THE UPPER 50S TO LOWER
60S WHICH IS CLOSE TO PERSISTENCE.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 332 PM EDT THU MAY 2 2013
FORECAST FOCUS CONTINUES TO BE ON RAIN CHANCES FRIDAY...AND OVER THE
WEEKEND. MODELS DEEPEN THE UPPER TROUGH OVER THE PLAINS INTO A
CLOSED UPPER LOW AND TRACK IT TOWARDS SOUTHERN TENNESSEE AND
NORTHERN MISSISSIPPI. MODELS HAVE TRENDED A LITTLE FARTHER SOUTH
WITH THE TRACK...ESPECIALLY THE GFS. AS A RESULT...IT LOOKS LIKE THE
HEAVIEST RAINS WILL BE ACROSS OUR SOUTH AND ANY RAIN THAT MAKES IT
INTO OUR NORTHEAST WILL BE LIGHT.
ON FRIDAY WILL MENTION LIKELY POPS...FAR WEST...CHANCE POPS
ELSEWHERE...BUT DRY OR SLIGHT CHANCE POPS FAR EAST. WENT CLOSER TO
SLIGHTLY WARMER MET TEMPERATURES EAST AS THERE WILL STILL BE SOME
SUN.
THERE WILL BE BETTER CHANCES OF SHOWERS OVER THE WEEKEND CENTRAL AND
SOUTH AS THE UPPER LOW MOVES A LITTLE CLOSER. WENT WITH LIKELY POPS
FROM INDY AND SOUTH AND WEST AND CHANCE POPS ELSEWHERE. WENT CLOSE
TO A MOS BLEND ON TEMPERATURES. HIGH TEMPERATURES COULD BE A LITTLE
WARMER ACROSS OUR NORTHEAST...BECAUSE PRECIPITATION THERE WILL BE
SCATTERED AT BEST.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 335 AM EDT THU MAY 2 2013
ENSEMBLES ARE SHOWING BETTER AGREEMENT ON A LARGE UPPER LOW SLOWLY
PASSING ACROSS THE TENNESSEE VALLEY FROM WEST TO EAST DURING THE
LONG TERM. SURFACE LOWS ARE STILL SHOWING QUITE A BIT OF SCATTER
SUNDAY NIGHT BUT SEEM TO COME INTO BETTER AGREEMENT BY MONDAY NIGHT
ON A LOCATION SOUTHEAST OF INDIANA AND MOVING FURTHER EAST AND AWAY
FROM THE AREA BY MIDDAY TUESDAY. THIS SHOULD ALLOW FOR POPS TO DROP
TO SLIGHT CHANCE OR LESS FROM MONDAY NIGHT ON. DURING THE DAYS SOME
INSTABILITY MAKES ITS WAY INTO THE SOUTHERN COUNTIES SO INCLUDED A
SLIGHT CHANCE OF THUNDER AT THAT TIME. SUNDAY NIGHT AND MONDAY THERE
IS SUFFICIENT FORCING FROM THE PROXIMITY OF THE UPPER AND SURFACE
LOWS TO JUSTIFY HIGH CHANCE POPS ACROSS THE SOUTH WITH LOWER CHANCES
AS YOU HEAD NORTH. FOR TEMPERATURES GENERALLY WENT WITH
ALLBLEND...WITH A SLIGHT ADJUSTMENT DOWN FOR HIGHS ON MONDAY WITH
THE UPPER LOW TO THE SOUTH AND MOSTLY CLOUDY SKIES.
&&
.AVIATION /DISCUSSION FOR THE 03/06Z TAFS/...
ISSUED AT 107 AM EDT FRI MAY 3 2013
MAINLY VFR THROUGH THE PERIOD OUTSIDE OF SHOWERS/THUNDERSTORMS.
BOUNDARY IS NEARLY STATIONARY JUST TO OUR NORTHWEST/WEST WITH WEAK
LOW PRESSURE ALONG IT. THIS BOUNDARY SERVED AS FOCUS FOR SCATTERED
CONVECTIVE DEVELOPMENT TO OUR WEST YESTERDAY AFTERNOON WITH SLOW AND
ERRATIC STORM MOTIONS IN AN UNSTABLE BUT VERY WEAKLY SHEARED
ENVIRONMENT. WITH LOSS OF HEATING...INTENSITY OF STORMS HAS BEEN
STEADILY DIMINISHING...ONLY SHOWERS LIKELY TO REMAIN BY ISSUANCE
TIME NEAR HUF/LAF...SO WILL CARRY VCSH THERE.
OVERNIGHT IN GENERAL EXPECTING JUST AN INCREASE IN CLOUD COVER. WINDS
WILL BECOME LESS THAN 10KT AT IND...LIGHT AND VARIABLE AT THE
OUTLYING SITES.
WILL CONTINUE WITH VCTS/CB MENTION TOMORROW AS THIS BOUNDARY SHOULD
MAKE SOME VERY SLOW EASTWARD PROGRESS. WINDS WILL BE 8-12KT TOMORROW
OUT OF THE SOUTHEAST.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH/SMF
SHORT TERM...JH
LONG TERM....CP
AVIATION...NIELD
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1232 AM CDT FRI MAY 3 2013
.SYNOPSIS...
ISSUED AT 351 PM CDT THU MAY 2 2013
12Z UA ANALYSIS HAS 850MB LOWS ALONG THE KS/MO BORDER AND ANOTHER IN
WESTERN OKLAHOMA. A VERY STRONG 850MB THERMAL GRADIENT RAN FROM
MN/WI DOWN TO OKLAHOMA AND WEST TEXAS. SATELLITE TRENDS THROUGH MID
AFTERNOON SHOW THE LOW CLOUDS MAKING SLOW PROGRESS EASTWARD. RADAR
SHOWS THE MAIN RAIN SHIELD OVER CENTRAL AND NORTHEAST IOWA WITH
SCATTERED CONVECTION ACROSS ILLINOIS AND EASTERN IOWA.
18Z SFC ANALYSIS HAS WEAK LOWS FROM LOWER MICHIGAN BACK INTO
NORTHEAST ARKANSAS WITH THE FRONT CONNECTING ALL THE LOWS. DEW
POINTS ACROSS THE PLAINS AND PARTS OF THE UPPER MIDWEST WERE IN THE
20S AND 30S WITH 40S AND HIGHER FROM THE GREAT LAKES INTO THE LOWER
MISSISSIPPI VALLEY.
08
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 351 PM CDT THU MAY 2 2013
VERY DIFFICULT FCST. REFER TO THE CLIMATE SECTION FOR INFORMATION
REGARDING MAY SNOW FOR SOME LOCATIONS.
THE TRENDS WITH THE MODELS IS COLDER. THE MAIN PRECIPITATION SHIELD
IS ALONG AND BEHIND THE 850MB FRONT. THE RAP AND WRF TRENDS HAVE
THIS FRONT SLOWLY MOVING EAST TONIGHT. THUS RAIN WILL SLOWLY BREAK
OUT AND INCREASE IN AREAL COVERAGE DURING THE EVENING HOURS.
WBZ TEMPERATURES AND ACTUAL OBSERVATIONS SHOW TREMENDOUS EVAPORATIVE
COOLING WILL OCCUR ACROSS THE FAR NORTHWEST AND WESTERN PARTS OF THE
CWFA TONIGHT. FCST SOUNDINGS INDICATE RAIN BECOMING MIXED WITH AND
THEN CHANGING OVER TO SLEET/SNOW MIXTURE. THE OVERALL FORCING AND
WAA ALOFT IS SIGNIFICANT SO THERE WILL LIKELY BE ACCUMULATIONS ON
GRASSY SURFACES EVEN THOUGH THE GROUND IS QUITE WARM.
THEREFORE...WINTER WEATHER ADVISORIES HAVE BEEN RAISED FOR THE
WESTERN TWO ROWS OF COUNTIES FROM HWY 92 ON NORTH.
BUCHANAN...BENTON...IOWA...AND KEOKUK COUNTIES HAVE THE BEST CHANCE
AT SEEING POTENTIALLY HISTORIC SNOWFALL FOR MAY. THE HIGHEST
SNOWFALL AMOUNTS WILL BE IN THE WESTERN PARTS OF THESE COUNTIES.
SNOW/SLEET AMOUNTS THERE COULD RANGE FROM 1 TO 4 INCHES.
FURTHER EAST...ACROSS DELAWARE...LINN...JOHNSON...AND WASHINGTON
COUNTIES THE CHANGE OVER TO SLEET WILL OCCUR DURING THE EVENING. IN
THIS AREA MORE SLEET THAN SNOW IS EXPECTED WITH THE HIGHER AMOUNTS
IN THE WESTERN PARTS OF THESE COUNTIES. SNOW/SLEET AMOUNTS IN THIS
AREA COULD RANGE FROM A DUSTING TO 1 INCH.
THE OVERALL LARGE PICTURE SUGGESTS THE POTENTIAL FOR SOME SLEET AS
FAR EAST AS A DUBUQUE IOWA TO KAHOKA MISSOURI LINE DUE TO
EVAPORATIVE COOLING. IN THIS AREA ONLY TRACE AMOUNTS ARE EXPECTED.
ROUGHLY ALONG AND EAST OF THE MISSISSIPPI...SHOWERS WILL GIVE WAY TO
A WIDESPREAD RAIN AS THE WAA INCREASES.
FRIDAY...THE SNOW/SLEET MIXTURE IN THE FAR NORTHWEST/WEST PARTS OF
THE CWFA WILL CHANGE BACK TO ALL RAIN AS WARM AIR ALOFT MOVES INTO
THE AREA. ACROSS THE EASTERN CWFA THE OVERALL FORCING INCREASES AS A
SFC WAVE MOVES UP FROM THE SOUTH. ALTHOUGH NOT INCLUDED IN THE
FORECAST...THE LIFT TOOL SUGGESTS POSSIBLY SOME ISOLATED THUNDER
OVER THE FAR SOUTHEAST AND EASTERN PARTS OF THE CWFA AS STRONG
CONVERGENCE MOVES ALONG A THETA E GRADIENT.
08
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 351 PM CDT THU MAY 2 2013
RECORD COLD RAIN...SLEET...SNOW EVENT MAIN CHALLENGE THIS FORECAST.
OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH MAIN ISSUE THE
PHASING OF LATENT HEAT RELEASE AND STRONG EVAPORATIVE COOLING TO
DETERMINE WHAT FAR WESTERN SECTIONS RECEIVE SLEET AND SNOW TONIGHT.
VERIFICATION AT 18Z SUPPORTS FORCING AND THERMAL FIELDS OF 12Z NAM-
WRF AND HI-RES ECMWF. THIS SUPPORTS SOME ACCUMULATIONS OF SNOW AND
QUITE A BIT OF SLEET FAR WEST SECTIONS. HEAVY RAIN AND FORCING
TOOLS SUGGEST MOST OF AREA TO PICK UP 1.5 TO LOCALLY AROUND 2.5
INCHES OF TOTAL PRECIPITATION NEXT 2-3 DAYS WITH MOST FALLING
FRIDAY AND FRIDAY NIGHT. STRATIFORM NATURE AND AMOUNTS OVER LONGER
TIME PERIOD SUPPORT MINOR RIVER ISSUES ON SOME RIVERS.
FRIDAY NIGHT...KEPT CATEGORICAL POPS WITH DEEPLY OCCLUDING AND
MATURING RAIN OF UPPER LOW TO DEPOSIT MOSTLY 1/3 TO 2/3 OF AN INCH
WITH HEAVIEST OVER SW 1/2 TO 2/3 OF AREAL TEMPERATURES WITH MILDER
AIR FROM EAST TO ALLOW TEMPERATURES TO BE NEARLY STEADY WITH LOWER
50S EAST TO MID/UPPER 40S FAR WEST.
SATURDAY AND SUNDAY...MINOR CHANGES MADE. CONSIDERABLE CLOUDS WITH
PERIODS OF LIGHT RAIN SATURDAY AND SATURDAY AND VERY LIGHT RAIN
SUNDAY. A QUARTER INCH OR LESS ON SATURDAY MOST LOCATIONS WITH
SPOTTY VERY LIGHT AMOUNTS SUNDAY. TEMPERATURES COOL WITH MOSTLY
LOWER TO MIDDLE 60S AND MINS SATURDAY NIGHT IN THE MID/UPPER 40S.
NICHOLS
DAYS 4 THROUGH 7...SUNDAY NIGHT THROUGH THURSDAY...
SUNDAY NIGHT THROUGH MONDAY NIGHT THE DEEP UPPER LOW GRADUALLY
SHIFTS SOUTHEAST...AND A SURFACE RIDGE BUILDS INTO THE AREA TO CAUSE
OUR SCATTERED SHOWERS TO SLOWLY DIMINISH IN COVERAGE...SO THAT BY
MONDAY NIGHT WE SHOULD BE COMPLETELY DRY. TEMPERATURES TO REMAIN
BELOW NORMAL WITH LOWS IN THE 40S. MONDAY HIGHS ARE CURRENTLY
FORECAST TO RISE INTO THE UPPER 60S...BUT IT TOO MUCH CLOUD COVER IS
LINGERING WILL HAVE TO LOWER THESE VALUES.
TUESDAY AND TUESDAY NIGHT THE SURFACE RIDGE SLOWLY SHIFTS EAST
ACROSS THE AREA...PRODUCING MAINLY DRY CONDITIONS AND GRADUALLY
WARMING TEMPERATURES. AM CARRYING SOME DAYTIME SLIGHT CHANCE POPS
IN THE SOUTHWEST CLOSEST TO THE LINGERING PLUME OF MOISTURE WHERE WE
MIGHT GET SOME DIURNALLY DRIVEN SHOWERS. HIGHS TUESDAY SHOULD GET
APPROACH 70 WITH 850MB TEMPERATURES GRADUALLY WARMING AS WELL.
TUESDAY NIGHT MINS TO MODERATE TO AROUND 50.
WEDNESDAY AND THURSDAY QUITE A BIT OF UNCERTAINTY RE-ENTERS THE
FORECAST. WE WILL BE IN A SPLIT FLOW WITH A NORTHERN STREAM MAINLY
AFFECTING SOUTHERN CANADA AND THE FAR NORTHERN CONUS...AND THE
SOUTHERN STREAM MAINLY AFFECTING THE SOUTHERN CONUS. MODELS ARE
DIVERGING IN THE HANDLING OF A SHORTWAVE THAT MOVES THROUGH THE
NORTHERN STREAM...AND HOW MUCH IT PHASES WITH A CUT OFF LOW IN THE
SOUTHERN STREAM OVER THE SOUTHWEST CONUS. THE ECMWF IS FASTER AND
IS PHASING IT MORE...AND DRAGGING MORE MOISTURE UP INTO THE
AREA...PRODUCING PRECIPITATION BEGINNING WEDNESDAY NIGHT. THE GFS
IS SLOWER AND PHASES IT LESS...AND DOES NOT BRING PRECIPITATION INTO
THE AREA UNTIL THURSDAY NIGHT. THUS...WHILE I AM CARRYING SOME
SLIGHT CHANCE POPS BEGINNING ON WEDNESDAY...THESE ARE MORE FOR A
CONTINUATION OF THE DIURNAL SHOWERS DURING THE DAY WITH THE
GRADUALLY INCREASING MOISTURE. AM BRINGING IN SOME LOW CHANCE POPS
FOR THURSDAY IN ASSOCIATION WITH THE NEW SHORTWAVE. TEMPERATURES TO
CONTINUE TO WARM THROUGH AT LEAST WEDNESDAY NIGHT...WITH HIGHS ON
WEDNESDAY INTO THE LOWER 70S. THURSDAY STILL FAIRLY WARM IN THE
FORECAST BUT THIS MAY NEED TO BE LOWERED IF PRECIPITATION MOVES INTO
THE AREA SOONER.
LE
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1230 AM CDT FRI MAY 3 2013
AN AREA OF RAIN SHOWERS CONTINUES TO DEVELOP AND SPREAD NORTH
AFFECTING EASTERN IOWA AND WESTERN ILLINOIS. THE RAIN CONTINUES TO
INCREASE IN COVERAGE AND PERIODS OF RAIN ARE EXPECTED THROUGHOUT
FRIDAY AS THE UPPER LEVEL SYSTEM MOVES INTO THE REGION. JUST A BIT
FURTHER WEST A MIX OF WINTRY PRECIPITATION HAS BEEN REPORTED WITH
SOME SLEET AND SNOW...AND LIGHT FREEZING RAIN AS FAR EAST AS KCID. THE
MAIN BAND OF SNOW CONTINUES TO EDGE EAST FROM CENTRAL IOWA.
HOWEVER THE WINTRY PRECIPITATION IS EXPECTED TO REMAIN WEST OF
KDBQ. A RETURN TO LIQUID PRECIPITATION IS THEN FORECAST AS WARMER
TEMPERATURES WORK BACK IN FROM EAST TO WEST BY MID FRIDAY MORNING.
MAINLY IFR CONDITIONS ARE EXPECTED WITH POTENTIAL FOR LIFR
CONDITIONS AT TIMES THROUGH FRIDAY.
STOFLET
&&
.CLIMATE...
ISSUED AT 351 PM CDT THU MAY 2 2013
MAY SNOWFALL IN IOWA IS RARE.
A VERY QUICK LOOK BACK AT PAST WEATHER RECORDS SUGGESTS THAT THE
LAST TIME A FAIRLY WIDESPREAD SNOW OCCURRED IN MAY ACROSS IOWA WAS
IN 1966. BELOW IS WHEN MEASURABLE SNOW AND/OR SLEET FELL IN MAY
FOR SELECTED SITES.
CEDAR RAPIDS #1 (MARION)...
0.2 INCHES 05/01/1997 FELL AS SLEET
0.3 INCHES 05/11/1966
DUBUQUE IOWA...
3.1 INCHES 05/01/1966
1.0 INCHES 05/07-08/1960
IOWA CITY WWTP...
0.2 INCHES 05/05/1944
MOLINE ILLINOIS...
0.3 INCHES ON 05/03/1935
TRACE ON 05/06/1989
TRACE ON 05/22/1917*
* LATEST RECORDED SNOWFALL ON RECORD
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...WINTER WEATHER ADVISORY UNTIL 10 AM CDT THIS MORNING FOR BENTON-
BUCHANAN-IOWA-KEOKUK.
WINTER WEATHER ADVISORY UNTIL 8 AM CDT THIS MORNING FOR DELAWARE-
JOHNSON-LINN-WASHINGTON.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...NICHOLS/LE
AVIATION...STOFLET
CLIMATE...08
AREA FORECAST DISCUSSION...CORRECTED
NWS DULUTH MN
408 AM CDT FRI MAY 3 2013
.SHORT TERM...TODAY THROUGH SATURDAY.
AT 4 AM...IT WAS FAIRLY QUIET ACROSS THE NORTHLAND. THERE WAS SOME
LIGHT SNOW ACROSS NW WI...AND REPORTS JUST OUTSIDE OF THE CWA OF
SOME LIGHT FREEZING DRIZZLE. TEMPERATURES RANGED FROM THE 20S IN
NE MN TO AROUND 30 IN NW WI.
THE NEXT MAIN WAVE OF PRECIPITATION WAS QUICKLY STREAMING
NORTHWARD THROUGH THE PLAINS. WE SHOULD SEE AN INCREASE
THROUGHOUT THE MORNING ACROSS WESTERN WISCONSIN. DEFINITELY SOME
PTYPE ISSUES...AND A THOROUGH ASSESSMENT OF THE FORECAST SOUNDINGS
SHOW SOME PRETTY SIGNIFICANT DIFFERENCES AMONG THE MODELS. JUST A
FEW DEGREES DIFFERENCE IN THE WARM LAYER WILL MEAN A CHANGE FROM
FREEZING RAIN OR RAIN...TO SLEET AND/OR SNOW.
FOR TODAY...HAVE RAISED POPS A BIT THROUGHOUT THE DAY...FIRST WITH
LIKELY POPS IN THE EASTERN 1/3 OF THE CWA...AND THEN SPREADING IT
NORTHWARD AND WESTWARD AS THE MORNING WEARS ON. NAM BUFR SOUNDINGS
AND THE HRRR FORECAST PTYPE INDICATE THAT A MIXTURE COULD LAST
INTO THE AFTERNOON...AND THERE MAY BE SOME SLEET AS WELL.
FORECAST LAYER THICKNESS VALUES ALSO INDICATE SOME POTENTIAL FOR
THIS TO LAST INTO THE AFTERNOON AND EVEN TONIGHT. WILL EXTEND THE
ADVISORY TIME THROUGH NOON WITH THE CAVEAT THAT SOME AREAS MAY
NEED TO BE EXTENDED INTO THE AFTERNOON.
HAVE INCREASED POPS CONSIDERABLY TONIGHT AND ON SATURDAY...WITH
GENERALLY RAIN DURING THE EVENING AND RAIN AND/OR FREEZING RAIN
AFTER MIDNIGHT. IN GENERAL...WE SHOULD SEE MAINLY RAIN ON
SATURDAY. TEMPS WILL BE TRICKY DUE TO THE CLOUDS AND EXPECTED
PRECIPITATION.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
A TROUGH OF LOW PRESSURE AND BAROCLINIC ZONE IS EVIDENT SATURDAY
NIGHT...WEAKENING SUNDAY. THIS WILL LEAD TO A CHANCE FOR RAIN OVER
MUCH OF THE CWA SATURDAY NIGHT...DIMINISHING FROM NORTH TO SOUTH
SUNDAY. RIDGING WILL TAKE OVER MONDAY INTO MONDAY NIGHT AND LEAD TO
A DRY PERIOD.
CONFIDENCE DIMINISHES MONDAY NIGHT INTO AT LEAST MID WEEK...AS THE
ECMWF BRINGS IN A SHORTWAVE AND SUPPORTS THE CHANCE FOR SHOWERS
TUESDAY/WEDNESDAY. WE FOLLOWED CLOSER TO THIS SOLUTION DURING THAT
PERIOD.
THE MODELS THEN HAVE A FASTER WNW FLOW OVER FAR NORTHERN MN/SOUTHERN
CANADA BY LATE IN THE WEEK WITH A CONTINUED CHANCE FOR RAIN WITH
WEAK LOW PRESSURE AT THE SURFACE. WE HAVE POPS CONTINUING THROUGH
THE REST OF THE PERIOD...ALTHOUGH WERE NOT OVERLY IMPRESSED WITH THE
FORCING AND EXPECTED PRECIPITATION AMOUNTS.
TEMPERATURES WILL BE A BIT BELOW NORMAL SUNDAY...RISING INTO THE
SIXTIES MONDAY THROUGH THE END OF THE WEEK.
&&
.AVIATION...06Z TAFS
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A WINTRY
MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY EARLY
FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW WISCONSIN
WILL LIKELY CONTINUE THROUGH FRIDAY.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD...AND THEN INTO THE KBRD AND KHIB AREAS IN THE AFTERNOON OR
EVENING. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY BE
-RA.
&&
.HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY WILL SLOW
THE MELT...BUT TEMPS WILL START TO WARM THIS WEEKEND INTO NEXT
WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 40 32 40 36 / 40 80 60 50
INL 47 29 51 33 / 10 20 10 10
BRD 49 34 45 38 / 10 60 60 40
HYR 42 32 44 34 / 80 80 60 30
ASX 37 32 39 33 / 70 80 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL NOON CDT TODAY FOR WIZ002>004-
007>009.
LS...SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ143>146.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-147-148.
&&
$$
SHORT TERM...DAP
LONG TERM....MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
406 AM CDT FRI MAY 3 2013
.SHORT TERM...TODAY THROUGH WEDNESDAY.
AT 4 AM...IT WAS FAIRLY QUIET ACROSS THE NORTHLAND. THERE WAS SOME
LIGHT SNOW ACROSS NW WI...AND REPORTS JUST OUTSIDE OF THE CWA OF
SOME LIGHT FREEZING DRIZZLE. TEMPERATURES RANGED FROM THE 20S IN
NE MN TO AROUND 30 IN NW WI.
THE NEXT MAIN WAVE OF PRECIPITATION WAS QUICKLY STREAMING
NORTHWARD THROUGH THE PLAINS. WE SHOULD SEE AN INCREASE
THROUGHOUT THE MORNING ACROSS WESTERN WISCONSIN. DEFINITELY SOME
PTYPE ISSUES...AND A THOROUGH ASSESSMENT OF THE FORECAST SOUNDINGS
SHOW SOME PRETTY SIGNIFICANT DIFFERENCES AMONG THE MODELS. JUST A
FEW DEGREES DIFFERENCE IN THE WARM LAYER WILL MEAN A CHANGE FROM
FREEZING RAIN OR RAIN...TO SLEET AND/OR SNOW.
FOR TODAY...HAVE RAISED POPS A BIT THROUGHOUT THE DAY...FIRST WITH
LIKELY POPS IN THE EASTERN 1/3 OF THE CWA...AND THEN SPREADING IT
NORTHWARD AND WESTWARD AS THE MORNING WEARS ON. NAM BUFR SOUNDINGS
AND THE HRRR FORECAST PTYPE INDICATE THAT A MIXTURE COULD LAST
INTO THE AFTERNOON...AND THERE MAY BE SOME SLEET AS WELL.
FORECAST LAYER THICKNESS VALUES ALSO INDICATE SOME POTENTIAL FOR
THIS TO LAST INTO THE AFTERNOON AND EVEN TONIGHT. WILL EXTEND THE
ADVISORY TIME THROUGH NOON WITH THE CAVEAT THAT SOME AREAS MAY
NEED TO BE EXTENDED INTO THE AFTERNOON.
HAVE INCREASED POPS CONSIDERABLY TONIGHT AND ON SATURDAY...WITH
GENERALLY RAIN DURING THE EVENING AND RAIN AND/OR FREEZING RAIN
AFTER MIDNIGHT. IN GENERAL...WE SHOULD SEE MAINLY RAIN ON
SATURDAY. TEMPS WILL BE TRICKY DUE TO THE CLOUDS AND EXPECTED
PRECIPITATION.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
A TROUGH OF LOW PRESSURE AND BAROCLINIC ZONE IS EVIDENT SATURDAY
NIGHT...WEAKENING SUNDAY. THIS WILL LEAD TO A CHANCE FOR RAIN OVER
MUCH OF THE CWA SATURDAY NIGHT...DIMINISHING FROM NORTH TO SOUTH
SUNDAY. RIDGING WILL TAKE OVER MONDAY INTO MONDAY NIGHT AND LEAD TO
A DRY PERIOD.
CONFIDENCE DIMINISHES MONDAY NIGHT INTO AT LEAST MID WEEK...AS THE
ECMWF BRINGS IN A SHORTWAVE AND SUPPORTS THE CHANCE FOR SHOWERS
TUESDAY/WEDNESDAY. WE FOLLOWED CLOSER TO THIS SOLUTION DURING THAT
PERIOD.
THE MODELS THEN HAVE A FASTER WNW FLOW OVER FAR NORTHERN MN/SOUTHERN
CANADA BY LATE IN THE WEEK WITH A CONTINUED CHANCE FOR RAIN WITH
WEAK LOW PRESSURE AT THE SURFACE. WE HAVE POPS CONTINUING THROUGH
THE REST OF THE PERIOD...ALTHOUGH WERE NOT OVERLY IMPRESSED WITH THE
FORCING AND EXPECTED PRECIPITATION AMOUNTS.
TEMPERATURES WILL BE A BIT BELOW NORMAL SUNDAY...RISING INTO THE
SIXTIES MONDAY THROUGH THE END OF THE WEEK.
&&
.AVIATION...06Z TAFS
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A WINTRY
MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY EARLY
FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW WISCONSIN
WILL LIKELY CONTINUE THROUGH FRIDAY.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD...AND THEN INTO THE KBRD AND KHIB AREAS IN THE AFTERNOON OR
EVENING. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY BE
-RA.
&&
.HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY WILL SLOW
THE MELT...BUT TEMPS WILL START TO WARM THIS WEEKEND INTO NEXT
WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 40 32 40 36 / 40 80 60 50
INL 47 29 51 33 / 10 20 10 10
BRD 49 34 45 38 / 10 60 60 40
HYR 42 32 44 34 / 80 80 60 30
ASX 37 32 39 33 / 70 80 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL NOON CDT TODAY FOR WIZ002>004-
007>009.
LS...SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ143>146.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-147-148.
&&
$$
SHORT TERM...DAP
LONG TERM....MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS DULUTH MN
1233 AM CDT FRI MAY 3 2013
.AVIATION...06Z TAFS
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A WINTRY
MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY EARLY
FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW WISCONSIN
WILL LIKELY CONTINUE THROUGH FRIDAY.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD...AND THEN INTO THE KBRD AND KHIB AREAS IN THE AFTERNOON OR
EVENING. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY BE
-RA.
&&
.PREV DISCUSSION... /ISSUED 1003 PM CDT THU MAY 2 2013/
UPDATE...
LIGHT SNOW CONTINUES TO FALL ACROSS NW WISCONSIN THIS EVENING. I
UPDATED THE FORECAST THROUGH THE REST OF TONIGHT. THE SNOW WILL
LIKELY CONTINUE THROUGH THE REST OF THE NIGHT. THERE HAS BEEN A
LITTLE BIT OF A LULL THIS EVENING...BUT THE MODELS AND RADAR
SUGGEST THE SNOW/PCPN RATES MAY PICK UP A BIT AGAIN AFTER
MIDNIGHT. THE LATEST NAM12 SOUNDINGS AND HRRR MODEL RUNS SUGGESTED
THE FREEZING RAIN MIGHT NOT BEGIN TO MOVE INTO NW WISCONSIN UNTIL
VERY LATE TONIGHT...SO I DELAYED ITS ARRIVAL.
THE MAIN CHALLENGE WITH THIS UPDATE WAS TO DETERMINE IF THE WINTER
WEATHER HEADLINES ARE STILL GOOD. MUCH OF NW WISCONSIN STILL HAS A
WINTER STORM WARNING WHICH IS IN EFFECT THROUGH FRIDAY MORNING.
WHILE ONLY LIGHT TO MODERATE SNOW IS EXPECTED THROUGH FRIDAY
MORNING...THE THREAT OF FREEZING RAIN LATER TONIGHT AND FRIDAY
MORNING HAS ME LEANING ON MAINTAINING THE CURRENT HEADLINES. THERE
IS A CHANCE THAT SIGNIFICANTLY MORE FREEZING RAIN COULD FALL THAN
FORECASTED. I THINK IT WOULD BE BEST TO FIRST MONITOR THE CHANGE
OVER TO MIXED PCPN LATER TONIGHT BEFORE MAKING CHANGES. THE NIGHT
SHIFT CAN REEVALUATE WHETHER OR NOT TO CHANGE THE CURRENT WARNINGS
AND ADVISORIES.
PREV DISCUSSION... /ISSUED 719 PM CDT THU MAY 2 2013/
UPDATE...
IT CONTINUES TO SNOW ACROSS NW WISCONSIN EARLY THIS EVENING. IT
ALSO APPEARS TO BE SNOWING LIGHT OVER THE EASTERN ARROWHEAD OF
MINNESOTA...BUT LITTLE TO NO ADDITIONAL ACCUMULATION IS EXPECTED
THROUGH THE REMAINDER OF THE NIGHT. THEREFORE...I LET THE WINTER
WEATHER ADVISORY FOR SOUTHERN COOK COUNTY EXPIRE AS PLANNED. I LET
THE WINTER STORM WARNINGS AND ADVISORY FOR COUNTIES IN NW
WISCONSIN CONTINUE THROUGH TOMORROW MORNING DUE TO THE EXPECTED
ADDITIONAL SNOW AND POTENTIAL FREEZING RAIN. THE LATEST NAM12
SOUNDINGS AND HRRR MODEL RUNS SEEM TO INDICATE THE FREEZING RAIN
MIGHT NOT BEGIN TO MOVE INTO NW WISCONSIN UNTIL VERY LATE
TONIGHT...SO I MIGHT DELAY ITS TIMING IN THE FORECAST WITH A LATER
UPDATE LATER THIS EVENING.
PREV DISCUSSION... /ISSUED 620 PM CDT THU MAY 2 2013/
AVIATION.../00Z TAF ISSUANCE/
A BAND OF PCPN OVER NW WISCONSIN THAT IS ASSOCIATED WITH A WINTER
STORM THAT HAS BEEN AFFECTING THE REGION SINCE LAST NIGHT WILL
CONTINUE THROUGH FRIDAY. THE SNOW WILL LIKELY TRANSITION TO A
WINTRY MIXTURE OF SNOW/SLEET/-FZRA LATE TONIGHT AND THEN TO -RA BY
EARLY FRIDAY AFTERNOON. WIDESPREAD IFR/MVFR CONDITIONS ACROSS NW
WISCONSIN WILL LIKELY CONTINUE THROUGH FRIDAY. UNFORTUNATELY...THE
OBSERVATION EQUIPMENT AT KHYR IS INOPERABLE...SO I AM UNABLE TO
KNOW WHAT IS EXACTLY HAPPENING AT KHYR. I PROVIDED A BEST GUESS
FORECAST FOR KHYR THROUGH FRIDAY...AND I WILL NOT BE PLANNING TO
MAKE ANY AMENDMENTS FOR THIS SITE.
WIDESPREAD LOW VFR CIGS IN THE 3 TO 4 KFT RANGE WILL PREVAIL
ACROSS NE MINNESOTA THROUGH AT LEAST TONIGHT IF NOT FRIDAY. THERE
MAY BE TIMES WHERE KDLH/KHIB/KINL FLIRT WITH MVFR CIGS. THE PCPN AND
MVFR CIGS OVER NW WISCONSIN WILL LIKELY BEGIN TO MOVE INTO KDLH
TOMORROW MORNING OR AFTERNOON AS THE BAND OF PCPN SPREADS
WESTWARD. BY THE TIME THE PCPN MOVES INTO KDLH...IT SHOULD MOSTLY
BE -RA.
PREV DISCUSSION... /ISSUED 351 PM CDT THU MAY 2 2013/
SHORT TERM...THROUGH EARLY FRIDAY EVENING.
WHAT AN IMPRESSIVE EVENT SO FAR...WITH MAX SNOWFALL SO FAR OF 16
INCHES 8 MILES SOUTH OF HAYWARD AND IN ASHLAND. I THINK IT`S
LIKELY THERE WILL BE SOME HIGHER TOTALS THAT COME IN AS ADDITIONAL
REPORTS FILTER IN LATE THIS AFTERNOON OR EVENING.
OVERALL...SNOWFALL INTENSITY WAS DIMINISHING WITH MOST OBSERVATIONS
SHOWING VSBYS AT OR ABOVE THREE QUARTERS OF A MILE. A SPOTTER
REPORTED THE SNOW HAD ENDED FOR NOW IN OGEMA IN SOUTHERN PRICE
COUNTY. WARM AIR ADVECTION AND A TROUGH SHOULD CAUSE PRECIPITATION
TO EXPAND OVERNIGHT OVER NORTHWEST WISCONSIN...AND THE WARMER AIR
ALOFT MOVING IN SHOULD CAUSE A WINTRY MIX TO OCCUR BY LATE TONIGHT
OR FRIDAY MORNING OVER MOST AREAS OF OUR WISCONSIN CWA. HEADLINES
WERE A CHALLENGE OVERNIGHT...AND WE OPTED TO EXTEND THE WARNING
FOR ASHLAND/BAYFIELD/IRON/SAWYER AND PRICE COUNTIES...RATHER THAN
CHANGE IT OVER TO AN ADVISORY. WE DID CHANGE WASHBURN TO AN
ADVISORY...AS MUCH OF THAT COUNTY HAS NOT HAD MUCH ADDITIONAL
SNOWFALL. WE`LL RELAY ADDITIONAL SNOWFALL AND POSSIBLE LIGHT ICE
ACCUMULATIONS IN THE HWO/STATEMENTS/ZONES/GRAPHICAST. WE EXPECT
ANOTHER INCH OR TWO TONIGHT/FRIDAY MORNING...WITH THAT SAME AMOUNT
POSSIBLE THIS AFTERNOON INTO EARLY EVENING.
MODELS ARE IN DECENT AGREEMENT THROUGH THE PERIOD...AND FINALLY ARE IN
GOOD AGREEMENT WITH THE EVOLUTION OF THE UPPER TROUGH THAT WILL
CUT OFF A LOW IN THE CENTRAL PLAINS TONIGHT INTO FRIDAY. THE GFS
WAS MUCH CLOSER THAN THE ECMWF WITH THIS A COUPLE DAYS AGO.
WE DELAYED THE WESTWARD MENTION OF POPS ON FRIDAY AS THE MODELS
KEEP THE BULK OF THE PRECIP OVER NORTHWEST WISCONSIN. WE EXPECT A
TRANSITION TO MAINLY RAIN BY AFTERNOON AS WARMER TEMPS ALOFT
CONTINUE TO ADVECT WEST AND BOUNDARY LAYER TEMPS WARM ABOVE
FREEZING.
LONG TERM...FRIDAY NIGHT THROUGH THURSDAY.
MAIN FOCUS IN EXTENDED IS THREAT FOR FZRA FRIDAY NIGHT AS ANOTHER
ROUND OF RAIN LIFTS NORTH OVER THE REGION. AT THIS TIME...THERE IS A
POTENTIAL FOR SOME LIGHT ICE ACCUM IS OVER THE WIS ZONES...AS WELL
AS IN THE MN ARROWHEAD WHERE SFC TEMPS LOOK TO FALL BELOW FREEZING
AS THE MID LEVELS QUICKLY WARM THROUGH THE NIGHT. AN ONSHORE FLOW
WITH WATER TEMPS IN THE MID 30S SHOULD KEEP AREAS NEAR LAKE SUPERIOR
WARM ENOUGH FOR ALL RA.
A COLD CORE LOW IN THE SOUTHERN STREAM...BECOMES CUT-OFF OVER THE SE
CONUS THROUGH THE WEEKEND. A H85 TROUGH AND REGION OF FGEN EXTENDING
NORTH FROM THE LOW...ACROSS THE NORTHLAND...WILL BE THE FOCUS FOR
ONGOING RAIN FRIDAY NIGHT THROUGH SATURDAY NIGHT. THE LATEST NAM/GFS
BOTH SHOW PWATS INCREASING FROM THE SOUTHEAST FRIDAY
NIGHT...REACHING AROUND AN INCH OVER THE SRN HALF OF THE FA BY SAT
AFTRN. MUCH OF THE NORTHLAND CAN EXPECT RAINFALL TOTALS ON THE ORDER
OF A HALF TO ONE INCH...WITH LOCALLY HIGHER AMOUNTS.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY INTO
FRIDAY WILL SLOW THE MELT...BUT TEMPS WILL START TO WARM THIS
WEEKEND INTO NEXT WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 42 32 39 35 / 20 80 60 40
INL 48 29 50 32 / 0 10 10 20
BRD 48 34 44 37 / 10 50 60 40
HYR 40 32 43 33 / 70 80 60 30
ASX 37 32 38 33 / 70 80 60 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER STORM WARNING UNTIL 11 AM CDT THIS MORNING FOR WIZ002>004-
008-009.
WINTER WEATHER ADVISORY UNTIL 11 AM CDT THIS MORNING FOR WIZ007.
LS...SMALL CRAFT ADVISORY FROM 4 AM EARLY THIS MORNING TO 1 AM CDT
SATURDAY FOR LSZ144>146.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-147-148.
&&
$$
AVIATION...GROCHOCINSKI/MELDE
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
106 AM EDT FRI MAY 3 2013
.SYNOPSIS...
STRONG HIGH PRESSURE WILL REMAIN ANCHORED NORTH OF THE REGION
TODAY THROUGH THE WEEKEND. AN APPROACHING LOW PRESSURE SYSTEM
WILL BRING UNSETTLED WEATHER TO THE CAROLINAS EARLY NEXT WEEK.
FAIR WEATHER IS EXPECTED TO FOLLOW THIS SYSTEM THROUGH THE MIDDLE
OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 106 AM FRIDAY...BASED ON LATEST KLTX AND SURROUNDING 88DS AND
THE LATEST HRRR OUTPUT AND THE 00Z NAM...THE BULK OF THE PCPN IN THE
FORM OF STRATIFORM R- AND L- TO REMAIN OVER THE ADJACENT ATLANTIC
WATERS. A TRAJECTORY RUNNING FROM ENE TO WSW FROM THE CURRENT PCPN
OVER THE ATL WATERS...WILL BRUSH ACROSS THE COASTAL COUNTIES
OVERNIGHT. WILL THE SLIGHT CHANCE ALONG THE IMMEDIATE COAST FOR ANY
ONSHORE MOVEMENT.
LATEST NAM MODEL AND GFS MOS INDICATES A RANGE OF LOWS FROM LOW TO
MID 50S NE PORTIONS OF THE CWA TO MID AND UPPER 50S SOUTHERN
PORTIONS. DEWPOINTS ONLY A FEW TICKS BELOW TEMPS DURING THE
OVERNIGHT. NE WINDS TO STAY ACTIVE OVERNIGHT ALONG WITH INTERVALS OF
CLOUDS...THUS PREVENTING ANY FOG DEVELOPMENT. POCKETS OF DRIZZLE
ALONG THE IMMEDIATE COAST OVERNIGHT COULD TEMPORARILY BRING DOWN
VSBYS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...MAIN FORECAST CHALLENGE IS THE POSSIBILITY
OF THE INTERVALS OF NUISANCE RAIN/DRIZZLE CONTINUING FOR THE NEXT
COUPLE OF DAYS. ALTHOUGH THERMAL PROFILES CONTINUE TO DRY
OUT...THE FACT THAT THE NATURE OF THE SHOWERS HAS BEEN AND IS VERY
SHALLOW. THIS ALMOST GOES WITHOUT SAYING WITH DRIZZLE. THE
GFS...NAM AS WELL AS SREF PLUME DIAGRAMS SHOW SMALL AREAS OF QPF
INDICATIVE OF THIS ACTIVITY CONTINUING THROUGH
SATURDAY...THEREFORE...I HAVE ADDED THIS TO THE FORECAST. TIMING
IS DIFFICULT BUT LEANED TOWARD THE NAM TO SHOW AN INCREMENTAL
DIFFERENCE WITH A SLIGHT INCREASE BOTH FRIDAY AND SATURDAY
MORNINGS. ONLY SMALL CHANGES TO TEMPERATURE FORECAST.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 3 PM THURSDAY...CLIMATOLOGICALLY UNUSUAL SETUP THROUGH MOST OF
THE PERIOD MAKING FOR SOME INTERESTING AND CHALLENGING FORECASTS.
DEEP CUTOFF UPPER LOW WILL APPROACH AND EVENTUALLY TRAVERSE THE
CAROLINAS...WHICH IS MUCH MORE TYPICAL OF WINTER OR MUCH EARLIER IN
THE SPRING. IT IS MORE THE ISOLATION FROM THE FLOW OF THIS FEATURE
RATHER THAN ITS UNUSUAL TIMING THAT MAKES THE FORECAST CHALLENGING
SINCE SUCH FEATURES ARE USUALLY POORLY HANDLED BY MODEL GUIDANCE.
THAT SAID THE MODELS HAVE COME INTO PRETTY GOOD AGREEMENT WITH THE
EVOLUTION OF THE PATTERN. THERE WILL STILL BE SOME FUTURE
REFINEMENTS IN THE TIMING POSSIBLE AND THE WEATHER ITSELF WILL BE
QUITE COMPLEX AS WE SHOULD GO THROUGH SOME DISTINCT REGIME CHANGES
THROUGH THE PERIOD. SUNDAY APPEARS TO BE THE LAST DAY IN THE
PRE FRONTAL FLOW AHEAD OF THE UPPER LOW. MOISTURE WILL BE RAPIDLY ON
THE RISE ESP ACCORDING TO THE RELATIVELY FASTER GFS. BEST FORCING IN
THE FORM OF MID LEVEL JETTING AND HEIGHT FALLS COME EITHER LATE
SUNDAY OR SUNDAY NIGHT INTO MONDAY AGAIN DEPENDING ON MODEL SOLN.
RAINFALL CHANCES AND QPF POTENTIAL ARE STARTING TO LOOK PRETTY GOOD
WITH SUCH STRONG FORCING AND DEEP ATLANTIC MOISTURE EXPECTED. THEN
THE SYNOPTIC SCALE DRY SLOT WILL MOVE ACROSS THE AREA SHUTTING OFF
THE RAINFALL FOR ABOUT A PERIOD. WE WILL THEN MOVE INTO A VERY
CONVECTIVE REGIME AS THE COLD POOL ALOFT CRAWLS ACROSS THE REGION.
RIGHT NOW BEST ESTIMATE IS THIS IS TUESDAY...WHICH COULD BE A BUSY
DAY WITH A RADAR SCOPE FULL OF SMALL HAIL PRODUCING SHALLOW TSTMS.
RAIN CHANCES WILL BE SMALLER FOR THE REMAINDER OF THE PERIOD AS THE
SLOW MOVING SYSTEM COULD STILL PLAGUE THE COASTAL CAROLINAS WITH
WRAP-AROUND MOISTURE.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
AS OF 05Z...LIGHT PRECIPITATION IS AGAIN MOVING ONSHORE NEAR KILM
BUT THE MAJORITY IS REMAINING OFFSHORE. SCATTERED LOW CLOUDS 1-2K
ARE
INCREASING UPSTREAM OF THE COASTAL TERMINALS WITH CLOUDS EXPANDING
WEST FROM THE PRECIPITATION AREA ALONG THE COAST. CIGS AND VSBYS ARE
CURRENTLY VFR.
HIGH PRESSURE WILL CONTINUE ACROSS THE TERMINALS THIS TAF VALID
PERIOD RESULTING IN A CONTINUED MOIST ENE-E LOW-MID LEVEL FLOW.
THERE IS MODERATE CONFIDENCE MVFR CIGS WILL DEVELOP AS ADVERTISED IN
TAFS WITH THE LOWEST CONFIDENCE IN TIMING. CONFIDENCE HAS LOWERED
THAT IFR WILL OCCUR AT THE COASTAL TERMINALS...ALTHOUGH IF ANY LIGHT
RAIN OCCURS THERE COULD BE TEMPO PERIODS OF IFR. BEST CONFIDENCE OF
IFR REMAIN AT KFLO. MVFR CONDITIONS WILL BE LIKELY AT ALL TERMINALS
THROUGH THE MORNING HOURS. ALL MODELS SUGGEST INCREASING MID LEVEL
MOISTURE AFTER 12Z INITIALLY AT THE COASTAL TERMINALS. THIS
COULD INCREASE THE CHANCES OF PRECIPITATION. SOME OF THIS
PRECIPITATION COULD MOVE WEST TO THE INLAND TERMINALS BY AFTERNOON.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS ESPECIALLY COASTAL
TERMINALS THROUGH SUNDAY. IFR/MVFR EARLY SUNDAY WITH RAIN/ISOLATED
THUNDERSTORMS DEVELOPING SUNDAY EVENING PERSISTING THROUGH MONDAY.
MVFR/TEMPO IFR POSSIBLE. VFR/TEMPO MVFR WITH SCATTERED SHOWERS
TUESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 106 AM FRIDAY...SCA EXTENDED FOR ALL WATERS TO 6 PM
SATURDAY...MAY 4TH.
PERSISTENCE THE WORD HERE FOR WINDS. CURRENT NE WINDS BASICALLY
REMAIN AT THESE SPEEDS FOR THE OVERNIGHT PERIOD. OF NOTE...HRRR
AND NAM INDICATE A MORE EASTERLY WIND DIRECTION AND 3 TO 5 KT
SUSTAINED HIER SPEEDS FOR THE ADJACENT OFFSHORE WATERS. THIS WILL
LIKELY HAVE IMPLICATIONS ON SIGNIFICANT SEAS
OVERNIGHT...ESPECIALLY THE OUTER WATERS OFF THE CAPES...FEAR AND
ROMAIN. OVERALL...HAVE INCREASED SIGNIFICANT SEAS BY 1
FOOT...HIGHEST AT 8 FT...ACROSS ALL WATERS...AND WOULD NOT BE
SURPRISED TO OBSERVE 2 FT HIER...HIGHEST AT 9 FT...MAINLY ACROSS
THE OUTER WATERS 15 TO 20 NM OUT FROM THE CAPES. AVERAGE PERIODS
OVERNIGHT WILL RUN 5 TO 6 SECONDS.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 PM THURSDAY...PERSISTENT NORTHEAST FLOW CONTINUES THROUGH
THE PERIOD. THERE MAY BE A LITTLE VEERING VERY LATE IN THE PERIOD
TO MORE OF A EASTERLY FLOW BUT OVERALL...THE NE FLOW WILL BE THE
STORY. STRONGEST WINDS WILL OCCUR FRIDAY WITH A FEW AREAS ACROSS
THE OUTER WATERS POSSIBLY EXCEEDING 25 KNOTS. FOR NOW THINK THESE
SPEEDS WILL BE LIMITED IN DURATION TO KEEP GALE CONSIDERATION IN
CHECK. SEAS WILL REMAIN RUGGED THROUGH THE PERIOD AND WILL ALMOST
CERTAINLY SEE THE SMALL CRAFT ADVISORY CONTINUE.
LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 3 PM THURSDAY...FAIRLY COMPLEX AND ACTIVE WEATHER EXPECTED FOR
MOST OF THE PERIOD ESPECIALLY EARLY ON. A DEEPLY CUTOFF UPPER SYSTEM
WILL APPROACH FROM THE WEST ON SUNDAY WITH A COLD FRONT ALONG ITS
LEADING EDGE. ONSHORE/EASTERLY FLOW WILL GET PINCHED BY THIS
APPROACHING BOUNDARY AS HIGH PRESSURE NOSED INTO THE CAROLINAS TRIES
TO HOLD ITS GROUND. AT SOME POINT THERE SHOULD BE SOME PRETTY SHARP
VEERING AS THE HIGH LOSES GROUND TO THE APPROACHING FRONT...AND THIS
IS PROBABLY THE MOST UNCERTAIN PART OF THE FORECAST. SOUTHERLY FLOW
SHOULD OVERSPREAD BY MONDAY WITH ADDITIONAL VEERING DUE TO THE
CYCLONIC CURVATURE OF THE ISOBARS COMING ACROSS THE CAROLINAS MONDAY
NIGHT INTO TUESDAY. ALL OF THE CHANGING OF THE WIND DIRECTION
THROUGH THE PERIOD SHOULD KEEP WAVE FACES RATHER STEEP AND PERIODS
SHORT MAKING FOR CHOPPY CONDITIONS. WHETHER OR NOT ANY CAUTIONARY
HEADLINES OR EVEN ADVISORIES ARE NEEDED TO TO WAVE HEIGHTS IS VERY
UNCERTAIN BUT WIND SPEEDS WILL REMAIN SHY OF EITHER.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR AMZ250-252-
254-256.
&&
$$
NEAR TERM...DCH/MJC
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...MRR/MJC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
856 AM MDT FRI MAY 3 2013
.UPDATE...
ISSUED AT 853 AM MDT FRI MAY 3 2013
UPDATED FORECAST TO TAKE DOWN THE FREEZE WARNING FOR THE REMAINDER
OF THIS MORNING AS TEMPERATURES CONTINUE TO RISE ABOVE FREEZING.
THERE IS STILL THE POTENTIAL FOR ANOTHER FROST OR FREEZE AGAIN
TONIGHT SO CURRENT FREEZE WATCH FOR TONIGHT WILL REMAIN IN EFFECT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM MDT FRI MAY 3 2013
CURRENTLY...CLEAR SKIES WITH NORTHERLY FLOW ALOFT AS THE UPPER
TROUGH SITS TO THE EAST OF COLORADO OVER KS AND NE...AS PER LATEST
SATELLITE IMAGERY AND H5 RAP ANALYSIS. WIDESPREAD BELOW FREEZING
TEMPS FOR THE EASTERN CO PLAINS AS OF 3 AM.
TODAY AND TONIGHT...NOT A LOT TO ADD TO THE ONGOING FORECAST PACKAGE
IN THE SHORT TERM. THE UPPER TROUGH TO THE EAST IS EXPECTED TO
STRENGTHEN AS IT EJECTS TO THE SE AWAY FROM CO...RELAXING THE WINDS
ALOFT FOR THE STATE. SUNNY TO MOSTLY SUNNY SKIES ARE EXPECTED
TODAY...WITH A NICE REBOUND FOR TEMPS INTO THE UPPER 50S TO MID 60S
FOR MOST LOCATIONS TODAY. LIGHT WINDS AND CLEAR SKIES TONIGHT WILL
PRODUCE ONE MORE NIGHT AND SUB-FREEZING TEMPS...AND CURRENT FREEZE
WATCH LOOKS GOOD. DECIDED TO HOLD OFF ON UPGRADING AT THIS
TIME...AND TO AVOID CONFUSION OPTED TO LET CURRENT WARNING RUN THE
COURSE...THEN AT EXPIRATION THE WATCH CAN BE UPGRADED. MOORE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM MDT FRI MAY 3 2013
...WETTER PATTERN POSSIBLE THIS PERIOD...
SIMULATIONS IN RATHER GOOD AGREEMENT GIVEN THE RATHER WEAK FLOW
REGIME WHICH WILL BE OVER THE WESTERN PART OF THE CONUS THIS
PERIOD. AT THE BEGINNING OF THIS PD (SAT 12Z)...A WELL ESTABLISHED
CUTOFF LOW WILL BE LOCATED IN THE VICINITY OF MISSOURI WHILE A
WEAKER CLOSED LOW WILL BE DEVELOPING OVER THE S IDAHO REGION. WEAK
RIDGING AND OVERALL WEAK MIDLVL FLOW WILL BE OVER THE FCST AREA.
AS THE WEEKEND PROGRESSES...THE LOW OVER MISSOURI WILL SLOWLY MOVE
EAST WHILE THE UPPER LOW OVER IDAHO RETROGRADES OVER N CALIF. THIS
WILL ALLOW FOR A SMALL MIDLVL RIDGE TO BUILD OVER THE FCST AREA.
GIVEN THIS PATTERN...I EXPECT IT WILL BE MAINLY DRY OVER THE
REGION. A FEW SCTD AFTERNOON AND EVENING TSRA WILL BE POSSIBLE
OVER THE CONTDVD AND AN ISOLATED STORM OR TWO WILL BE POSSIBLE
OVER THE S MTNS/PIKES PEAK REGION. DAYTIME TEMPS WILL BE PLEASANT
WITH MAINLY 60S ACROSS THE PLAINS AND VALLEYS.
DURING THE MONDAY TIMEFRAME...A SHORTWAVE WILL EJECT OUT OF THE
CALIF LOW AND MOVE ACROSS THE REGION. I EXPECT WE WILL SEE
INCREASING CHANCES OF SHOWER OVER THE MTNS WITH ISOLATED SHOWERS
BECOMING POSSIBLE OVER THE PLAINS LATE IN THE DAY. MAX TEMPS MONDAY
WILL BE A FEW DEGREES WARMER THAN THE WEEKENDS HIGHS. SHEAR WILL BE
INCREASING MONDAY (ALTHOUGH NOT ALL THAT STRONG)...SO WE MAY SEE A
BIT MORE ORGANIZED CONVECTION ON THIS DAY ON THE PLAINS.
TUESDAY...CALIF LOW STARTS TO MOVE EAST AND SIMULATIONS HINT AT A
DRY SLOT AFFECTING THE S TIER OF THE CWA. THIS SHOULD BRING A
DECREASING THREAT OF SHOWERS TO THE REGION AND ALLOW FOR TEMPS TO
RISE INTO THE MID 70S ACROSS THE PLAINS WITH 60S VALLEYS.
WEDNESDAY IS WHEN THE MAIN LOW MOVES OVER THE STATE...AND THIS IS
THE DAY WE SHOULD SEE THE MOST ACTIVE WX. THERE IS NOT MUCH COLD AIR
WITH THIS SYSTEM SO ALL PRECIP (EXCEPT OVER THE HIGHEST TRRN) SHOULD
BE LIQUID. SHEAR IS FCST TO BE RATHER IMPRESSIVE (ESPECIALLY GFS) OVER
THE FAR E PLAINS AND IT IS POSSIBLE WE MAY SEE OUR FIRST SEVERE WX
THREAT OVER THE FCST AREA. THERE WILL ALSO BE A GOOD CHANCE OF
PRECIP OVER THE ENTIRE AREA GIVEN THE EXPECTED INSTABILITY AND
FORCING. FOR NOW I HAVE POPS IN THE 20-40% RANGE...BUT THESE VALUES
MAY NEED TO BE INCREASED IF MODELS CONTINUE TO SHOW THIS SCENARIO.
MAX TEMPS THIS DAY WILL BE COOLER GIVEN THE LIKELY INCREASED CLOUD
COVER OVER THE FCST AREA.
WED NITE THROUGH THU THE WEAK UPPER LOW MOVES VERY LITTLE AND WE
SHOULD SEE A CONTINUED THREAT OF MUCH NEED PRECIP OVER THE FCST
AREA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 300 AM MDT FRI MAY 3 2013
VFR CONDITIONS ARE FORECAST FOR THE THREE MAIN TAF SITES OF
KCOS...KPUB AND KALS FOR THE NEXT 24 HRS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
COZ084>089-093>099.
FREEZE WARNING UNTIL 9 AM MDT THIS MORNING FOR COZ083>089-
093>099.
&&
$$
UPDATE...KT
SHORT TERM...MOORE
LONG TERM...HODANISH
AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1052 AM EDT FRI MAY 3 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 345 AM EDT FRI MAY 3 2013
RAIN CHANCES WILL INCREASE ACROSS THE REGION THROUGH SUNDAY AS AN
UPPER LOW CUTS OFF OVER THE SOUTHERN PLAINS TODAY...THEN STRENGTHENS
AND DRIFTS SOUTHEAST INTO THE LOWER MISSISSIPPI VALLEY BY SUNDAY.
THE UPPER LOW WILL MOVE THROUGH THE CAROLINAS EARLY NEXT WEEK AND
OFF THE MID ATLANTIC COAST BY WEDNESDAY. HIGH PRESSURE WILL
REESTABLISH ACROSS THE OHIO VALLEY WITH WARMER DRIER WEATHER
RETURNING BY MIDWEEK.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 945 AM EDT FRI MAY 3 2013
MINOR TWEAKS MADE TO GRIDS...MAINLY SKY COVER...RAIN CHANCES AND
TEMPERATURES BASED ON SATELLITE...RADAR AND CURRENT CONDITIONS.
A COLD FRONT HAS PUSHED INTO THE NORTHWEST PART OF OUR FORECAST
AREA. HOWEVER ALL MODELS BACK IT WEST INTO ILLINOIS THIS AFTERNOON
AS LOW PRESSURE DEVELOPS OVER THE MID MISSISSIPPI VALLEY. WILL
LOWER TEMPERATURES A DEGREE OR TWO NORTHWEST AND FAR WEST FOR THIS
AFTERNOON. PREVIOUS NEAR TERM DISCUSSION FOLLOWS...
ABUNDANCE OF MID AND HIGH LEVEL CLOUD COVER ACROSS CENTRAL INDIANA
EARLY THIS MORNING. DEEPER MOISTURE NEAR AND WEST OF A QUASI-
STATIONARY FRONTAL BOUNDARY NOW DRAPED ACROSS THE WABASH VALLEY
SOUTHWEST INTO THE MISSISSIPPI RIVER VALLEY. TEMPERATURES WERE IN
THE 60S OVER MUCH OF THE FORECAST AREA AT 07Z...WITH THE EXCEPTION
OF UPPER 40S AND 50S OVER THE FAR NORTHWEST WHICH HAD SLIPPED BEHIND
THE FRONT.
FOCUS FOR TODAY WILL BE ON THE LOCATION OF THE FRONT AND POTENTIAL
FOR CONVECTIVE DEVELOPMENT ACROSS CENTRAL INDIANA. UPPER TROUGH
CONTINUING TO AMPLIFY OVER THE CENTRAL PLAINS THIS MORNING AND AS
ENERGY ALOFT DIVES INTO THE TROUGH TODAY EXPECT IT TO AMPLIFY AND
STRENGTHEN FURTHER...EVENTUALLY CUTTING OFF OVER SOUTHWEST MISSOURI
BY THIS EVENING. AT THE SURFACE...NEARLY STATIONARY BOUNDARY OVER
EXTREME WESTERN FORECAST AREA LIKELY TO MOVE LITTLE THROUGH THE
MORNING BEFORE RETROGRADING BACK TO THE WEST INTO ILLINOIS THIS
AFTERNOON AS THE UPPER LOW DEEPENS. SURFACE LOW PRESSURE CURRENTLY
DEVELOPING OVER NORTHERN MISSISSIPPI EARLY THIS MORNING WILL LIFT
NORTH THEN NORTHWEST ALONG THE BOUNDARY AND SHOULD BE NEAR KSTL BY
THIS EVENING.
REMAIN UNIMPRESSED IN POTENTIAL FOR WIDESPREAD RAINFALL FOR CENTRAL
INDIANA TODAY AS BULK OF THE DEEPEST MOISTURE WILL REMAIN CONFINED
ALONG AND TO THE WEST OF THE LOCATION OF THE BOUNDARY ALL DAY.
PREDOMINANT SOUTHEASTERLY LOW LEVEL FLOW WILL MAINTAIN SOME DEGREE
OF DRY AIR THROUGH THE BOUNDARY LAYER ACROSS MUCH OF THE REGION. LOW
LEVEL CONVERGENCE AND ISENTROPIC LIFT WILL REMAIN FOCUSED TO THE
SOUTHWEST OF THE FORECAST AREA TODAY AS A LOW LEVEL JET LIFTS INTO
THE MID MISSISSIPPI VALLEY. PRESENCE OF A FEW MID LEVEL VORT LOBES
ROTATING UP INTO THE REGION FROM THE SOUTH AND WEAK INSTABILITY LOOK
TO BE THE MAIN CATALYSTS FOR CONVECTIVE DEVELOPMENT TODAY. WILL
CARRY LIKELY POPS IN THE WABASH VALLEY THIS MORNING IN THE VICINITY
OF THE BOUNDARY AND CHANCE POPS ELSEWHERE. LOW/MID LEVEL LAPSE RATES
BRIEFLY INCREASE THIS AFTERNOON AND ALONG WITH THE INSTABILITY
PRESENT...SHOULD BE ENOUGH TO GENERATE SCATTERED LOW TOPPED
CONVECTION.
TEMPS...LOW LEVEL THERMALS ARE SUPPORTIVE OF MOS GUIDANCE TODAY WITH
HIGHS WARMING INTO THE 70S.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 345 AM EDT FRI MAY 3 2013
FORECAST CHALLENGES FOCUS ON POTENTIAL FOR RAIN AS THE UPPER LOW
TRACKS FROM THE OZARKS E/SE INTO THE SOUTHEAST STATES BY SUNDAY
NIGHT. OP GFS/GGEM/ECMWF ALL IN EXCELLENT AGREEMENT ON TRACK AND
STRENGTH OF THE UPPER LOW THROUGH THE SHORT TERM WITH THE 00Z NAM
BECOMING A SLOW OUTLIER BY SUNDAY.
AFOREMENTIONED SURFACE LOW WILL GET PULLED AWAY FROM THE REGION
TONIGHT AND SATURDAY BY THE UPPER LOW...WITH THE FRONTAL BOUNDARY
BECOMING STRETCHED AND EVENTUALLY WASHING OUT ACROSS THE LOWER OHIO
VALLEY BY LATE WEEKEND AS THE UPPER LOW MOVES INTO MISSISSIPPI. BEST
CHANCES FOR WIDESPREAD RAINFALL TO IMPACT CENTRAL INDIANA WILL COME
SATURDAY INTO EARLY SUNDAY AS DEEPER MOISTURE PIVOTS BACK NORTH INTO
THE SOUTHERN HALF OF THE FORECAST AREA AND COMBINES WITH A PERIOD OF
ISENTROPIC LIFT AND STRONG CONVERGENCE AT THE NOSE OF THE LOW LEVEL
JET. AN AXIS OF MID LEVEL DEFORMATION ALSO COMES INTO PLAY ON
SATURDAY AND ALIGNS JUST NORTH OF THE LOW LEVEL JET. CONFIDENCE IS
HIGHEST IN HEAVIER RAINFALL IMPACTING THE LOWER WABASH VALLEY
SATURDAY AND SATURDAY NIGHT...GRADUALLY DIMINISHING IN COVERAGE AND
INTENSITY GOING NORTH/EAST ACROSS THE FORECAST AREA FURTHER AWAY
FROM THE DEEPER PLUME OF MOISTURE AND BETTER FORCING. COULD SEE 1.5
TO 2 INCHES OF RAINFALL BY THE END OF THE WEEKEND OVER THE LOWER
WABASH VALLEY...DROPPING TO A HALF INCH OR LESS ALONG AND NORTH/EAST
OF INTERSTATE 74. WILL KEEP THUNDER MENTION OUT THROUGH THE PERIOD
AS POOR LAPSE RATES AND LITTLE TO NO INSTABILITY OVER THE OHIO
VALLEY.
WILL CARRY LIKELY POPS OVER SOUTHERN COUNTIES WITH DECREASING POPS
FURTHER NORTH/EAST. PRESENCE OF SUBSIDENCE AND DRIER AIR
TRANSPORTING INTO THE LOWER GREAT LAKES FROM THE EAST WILL LIKELY
CREATE A SHARP CUTOFF TO THE NORTHERN EXTENT OF THE PRECIP SHIELD.
VERY DISTINCT POSSIBILITY THAT NORTHEAST COUNTIES SEE LITTLE TO NO
RAINFALL TONIGHT THROUGH SUNDAY...ESPECIALLY IF MODEL TRENDS
CONTINUE WITH THE MORE SOUTHERN TRACK TO THE UPPER LOW OVER THE
WEEKEND. PRECIP COVERAGE WILL DIMINISH SUNDAY NIGHT AS DRIER AIR
WRAPS AROUND THE BACK SIDE OF THE UPPER LOW AND INTO THE REGION.
TEMPS...LEANED TOWARDS COOLER MAVMOS GUIDANCE ACROSS MUCH OF THE
AREA FOR HIGHS SATURDAY. DID UNDERCUT TEMPS HOWEVER OVER THE LOWER
WABASH VALLEY WITH EXPECTATION OF RAINFALL AND CLOUDS. UNDERCUT MOS
OVER ENTIRE FORECAST AREA SUNDAY AS SIMILAR BOUNDARY LAYER TEMPS TO
SATURDAY AND PRESENCE OF CLOUDS/RAIN SHOULD KEEP HIGHS A COUPLE
DEGREES COOLER THAN GUIDANCE. WENT A DEGREE OR TWO WARMER ON LOWS
TONIGHT AND SAT NIGHT AND NEAR MOS SUNDAY NIGHT.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 345 AM EDT FRI MAY 3 2013
RAIN SHOWERS AND ISOLATED THUNDERSTORMS ACROSS THE SOUTHERN COUNTIES
WILL BE POSSIBLE EARLY IN THE EXTENDED PERIOD AS A BROAD UPPER LEVEL
LOW CONTINUES TO AFFECT CENTRAL INDIANA. THE GFS AND EURO ARE IN
DECENT AGREEMENT WITH THE TRACK OF THE SYSTEM...TAKING THE UPPER LOW
OVER THE SOUTHEAST U.S. AND AN ACCOMPANYING SURFACE LOW OVER THE
TENNESSEE VALLEY. MODELS START TO DIFFER THOUGH ON THURSDAY AS THE
EURO BRINGS ANOTHER UPPER LEVEL LOW OVER THE UPPER MIDWEST...AND THE
GFS SHOWS RIDGING. FOR NOW...WILL STICK WITH LATEST INITIALIZATION
WHICH INCREASES POPS FROM WEST TO EAST STARTING THURSDAY AFTERNOON.
IN REGARD TO TEMPS...WAS ABLE TO CONTINUE WITH ALLBLEND...EXCEPT FOR
MONDAY/S HIGHS WHICH NEEDED ADJUSTING DOWN DUE TO CLOUD COVER OVER
THE SOUTH.
&&
.AVIATION /DISCUSSION FOR THE 03/1500Z TAF ISSUANCE/...
UPDATED TO REMOVE -TSRA FROM KHUF THIS AFTERNOON AND REPLACE WITH
VCTS...AND ALSO PUSHED BACK VCTS BY A BIT AT THE SITES BASED ON RAP
AND HRRR OUTPUT. PREVIOUS DISCUSSION FOLLOWS...
ISSUED AT 1052 AM EDT FRI MAY 3 2013
SCATTERED TO NUMEROUS SHOWERS AND ISOLATED THUNDERSTORMS /MAINLY
THIS AFTERNOON/ WILL IMPACT TAF SITES FOR DURATION OF TAF PERIOD AS
A STATIONARY BOUNDARY REMAINS DRAPED OVER WESTERN PORTIONS OF
CENTRAL INDIANA. NONETHELESS...ANTICIPATE VFR CONDITIONS TO BE THE
PREVAILING FLIGHT CATEGORY WITH ONLY BRIEF DETERIORATION TO MVFR AT
TIMES WITH HEAVIER SHOWERS/STORMS. THUNDERSTORMS SHOULD TAPER OFF
WITH LOSS OF DAYTIME HEATING...SO ONLY CARRIED MENTION OF RAIN AFTER
SAT 00Z. WINDS WILL BE SOUTHEASTERLY AT 8 TO 14 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...RYAN
NEAR TERM...RYAN/JH
SHORT TERM...RYAN
LONG TERM....TDUD
AVIATION...TDUD/CP
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1158 AM EDT FRI MAY 03 2013
.Forecast Update...
Issued at 1155 AM EDT Fri May 3 2013
12Z Models continue to advertise a sharp cutoff in precipitation on
the northeast side of the large band of rain expected to setup as
the upper low now over the Central Plains starts travelling
southeast. Have begun to trim pops over the northeast forecast area,
including a tweak downward for the Louisville area for tomorrow.
Pops over the south still look pretty solid. Given the slow-moving
nature of the line across our forecast area combined with heavy
rains that fell earlier, as well as ensemble guidance indicating
rivers across the south likely will go to flood stage, have decided
to go ahead and issue a flood watch across south central Kentucky.
Issued at 905 AM EDT Fri May 3 2013
Atmosphere much less capped than yesterday, as seen from the earlier
showers we had over the northwest forecast area this morning. The
limiting factor will be dry air over the east. The ARW and NMM
versions of the WRF as well as the latest RAP all have a band of
showers and storms forming at the edge of this dry air, which would
be along the I-65 corridor, later this afternoon.
As for the more steady rains coming in, models are fine tuning where
the band will set up and move (slowly). There looks to be a sharp
cutoff over the northeast, and the heaviest rains look to fall where
we`ve had plenty of rain already in the last month. Given that
earlier rain we may have to go with a flood watch across south
central Kentucky and will decide after seeing the 12Z model data.
Issued at 520 AM EDT Fri May 3 2013
Did a quick update to increase PoPs a bit across our western
sections due to the batch of showers moving northward through
southwestern Indiana. Also have some isolated showers that have
popped up on the east side of I-65 as well, so have also expanded
PoPs a little further east.
&&
.Short Term (Now through Saturday)...
Issued at 324 AM EDT Fri May 3 2013
In the near term, partly to mostly cloudy skies are expected to
persist across the region. Early morning radar imagery shows a few
isolated showers moving northward across our western CWA...mainly
west of I-65. We expect the isolated showers to continue through
the remainder of the early morning hours west of I-65. Temperatures
remained quite mild with readings in the upper 50s in the southeast
sections with lower 60s elsewhere. Temperatures will probably drop
another 1-2 degrees before hitting their overnight minimums.
Stalled out boundary out to our west is forecast to make very slow
progress eastward today, mainly staying out near the Mississippi
river. Southeasterly winds will pick up today as the pressure
gradient increases across the region. Plenty of clouds are expected
across the western half of the region today with a little less in
the east. Moisture plume out ahead of the slow moving boundary will
help generate waves of showers mainly to our west. Previous
forecast has a very good handle here with isolated-scattered showers
and possibly a thunderstorm or two mainly west of I-65 during the
afternoon hours. Current data still supports this, so only some
minor tweaks to the grids were made here. Temperatures this
afternoon will warm into the mid-upper 70s with the highest temps
out across the east where the veil of clouds is expected to be a bit
thinner.
By tonight, the frontal boundary out to the west is forecast to
start making some eastward progress as the deep closed low out over
the Plains gets more organized and deepens. Rain showers will be
most concentrated out across our western sections and then
overspread much of central Kentucky by sunrise Saturday. Light
southeasterly flow and plenty of cloud cover will result in mild
overnight minimum temperatures with readings cooling into the
mid-upper 50s.
Saturday, by all accounts, will be cloudy and wet across the region
as the surface frontal boundary occludes across the region. Band of
showers over western Kentucky is expected to gradually spread
eastward across the central part of the state throughout the day.
The rain will generally be light to moderate, but could be a little
heavy at times especially across southern Kentucky. Instability is
virtually not existent so not expecting much in the way of thunder.
However, with the good moisture fetch off the SW Atlantic, training
of rain showers looks increasingly likely which could lay down
around an inch of rain in some spots by Saturday evening. The
clouds and precipitation will keep temperatures down on Saturday
with highs only warming into the upper 50s.
.Long Term (Saturday Night through Thursday)...
Issued at 300 AM EDT Fri May 3 2013
The well advertised cutoff upper level low will be over Arkansas at
the beginning of the long term. This low will slowly swing across
the southeastern CONUS and into northern GA by Monday morning. It
will then work its way up the Atlantic coast through mid week.
The fetch of moisture off the Atlantic will continue to wrap around
the northern side of the low as it slides south of the forecast area
through the end of the weekend. Moderate rain will continue across
much of the area Saturday night through Sunday. Through this time
period an rainfall totals look to range from half an inch across
portions of the Bluegrass and southern Indiana to an inch south of
the Bluegrass Parkway. Some minor flooding will be possible on area
rivers with this rain. For more information refer to the hydrology
discussion below.
Rain chances will continue off and on through the first half of the
work week. However, these will become more diurnal in nature as the
low moves up the coast. A few thunderstorms will be possible with
this activity, especially if the sun is able to break out at all.
Thursday finally looks to be dry under ridging aloft.
Temperatures will remain on the cool side Sunday with highs only in
the lower 60s. However we will see a warming trend through the week.
By Thursday high temperatures should be back into the upper 70s with
lows in the mid to upper 50s.
&&
.Aviation (12Z TAF Issuance)...
Issued at 643 AM EDT Fri May 3 2013
Nearly stationary frontal boundary out near the MS river will remain
out to our west throughout the day. VFR conditions are expected at
all the terminals today with southeast winds picking up during the
mid-morning hours. The pressure gradient is expected to increase as
a deep upper low continues to strengthen over the Plains. Southeast
winds of 10-15 mph with gusts up to 20 mph will be possible later
this afternoon.
A few waves of low pressure will move up along the frontal boundary
producing a few rounds of showers later today. The vast majority of
this activity will stay west of KBWG and KSDF this afternoon.
Coverage still looks rather sparse enough to preclude mention in
this TAF forecast at the moment.
&&
.Hydrology...
Issued at 300 PM EDT Thu May 2 2013
An upper air disturbance is forecast to move across the region this
weekend. This will result in moderate to heavy rainfall over
southern Kentucky. Between Friday afternoon and Sunday morning
between one and inch inches could fall with the heaviest amounts
near Bowling Green.
This area recently had minor flooding and this new rain could result
in a new round of flooding in the middle of the Green River Basin.
Residents with livestock or equipment in flood prone areas should
watch water levels closely this weekend.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLOOD WATCH FROM SATURDAY MORNING THROUGH SUNDAY EVENING FOR
KYZ026-027-061>066-070>078-081-082.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
Hydrology........CMC
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
908 AM EDT FRI MAY 03 2013
.Forecast Update...
Issued at 905 AM EDT Fri May 3 2013
Atmosphere much less capped than yesterday, as seen from the earlier
showers we had over the northwest forecast area this morning. The
limiting factor will be dry air over the east. The ARW and NMM
versions of the WRF as well as the latest RAP all have a band of
showers and storms forming at the edge of this dry air, which would
be along the I-65 corridor, later this afternoon.
As for the more steady rains coming in, models are fine tuning where
the band will set up and move (slowly). There looks to be a sharp
cutoff over the northeast, and the heaviest rains look to fall where
we`ve had plenty of rain already in the last month. Given that
earlier rain we may have to go with a flood watch across south
central Kentucky and will decide after seeing the 12Z model data.
Issued at 520 AM EDT Fri May 3 2013
Did a quick update to increase PoPs a bit across our western
sections due to the batch of showers moving northward through
southwestern Indiana. Also have some isolated showers that have
popped up on the east side of I-65 as well, so have also expanded
PoPs a little further east.
&&
.Short Term (Now through Saturday)...
Issued at 324 AM EDT Fri May 3 2013
In the near term, partly to mostly cloudy skies are expected to
persist across the region. Early morning radar imagery shows a few
isolated showers moving northward across our western CWA...mainly
west of I-65. We expect the isolated showers to continue through
the remainder of the early morning hours west of I-65. Temperatures
remained quite mild with readings in the upper 50s in the southeast
sections with lower 60s elsewhere. Temperatures will probably drop
another 1-2 degrees before hitting their overnight minimums.
Stalled out boundary out to our west is forecast to make very slow
progress eastward today, mainly staying out near the Mississippi
river. Southeasterly winds will pick up today as the pressure
gradient increases across the region. Plenty of clouds are expected
across the western half of the region today with a little less in
the east. Moisture plume out ahead of the slow moving boundary will
help generate waves of showers mainly to our west. Previous
forecast has a very good handle here with isolated-scattered showers
and possibly a thunderstorm or two mainly west of I-65 during the
afternoon hours. Current data still supports this, so only some
minor tweaks to the grids were made here. Temperatures this
afternoon will warm into the mid-upper 70s with the highest temps
out across the east where the veil of clouds is expected to be a bit
thinner.
By tonight, the frontal boundary out to the west is forecast to
start making some eastward progress as the deep closed low out over
the Plains gets more organized and deepens. Rain showers will be
most concentrated out across our western sections and then
overspread much of central Kentucky by sunrise Saturday. Light
southeasterly flow and plenty of cloud cover will result in mild
overnight minimum temperatures with readings cooling into the
mid-upper 50s.
Saturday, by all accounts, will be cloudy and wet across the region
as the surface frontal boundary occludes across the region. Band of
showers over western Kentucky is expected to gradually spread
eastward across the central part of the state throughout the day.
The rain will generally be light to moderate, but could be a little
heavy at times especially across southern Kentucky. Instability is
virtually not existent so not expecting much in the way of thunder.
However, with the good moisture fetch off the SW Atlantic, training
of rain showers looks increasingly likely which could lay down
around an inch of rain in some spots by Saturday evening. The
clouds and precipitation will keep temperatures down on Saturday
with highs only warming into the upper 50s.
.Long Term (Saturday Night through Thursday)...
Issued at 300 AM EDT Fri May 3 2013
The well advertised cutoff upper level low will be over Arkansas at
the beginning of the long term. This low will slowly swing across
the southeastern CONUS and into northern GA by Monday morning. It
will then work its way up the Atlantic coast through mid week.
The fetch of moisture off the Atlantic will continue to wrap around
the northern side of the low as it slides south of the forecast area
through the end of the weekend. Moderate rain will continue across
much of the area Saturday night through Sunday. Through this time
period an rainfall totals look to range from half an inch across
portions of the Bluegrass and southern Indiana to an inch south of
the Bluegrass Parkway. Some minor flooding will be possible on area
rivers with this rain. For more information refer to the hydrology
discussion below.
Rain chances will continue off and on through the first half of the
work week. However, these will become more diurnal in nature as the
low moves up the coast. A few thunderstorms will be possible with
this activity, especially if the sun is able to break out at all.
Thursday finally looks to be dry under ridging aloft.
Temperatures will remain on the cool side Sunday with highs only in
the lower 60s. However we will see a warming trend through the week.
By Thursday high temperatures should be back into the upper 70s with
lows in the mid to upper 50s.
&&
.Aviation (12Z TAF Issuance)...
Issued at 643 AM EDT Fri May 3 2013
Nearly stationary frontal boundary out near the MS river will remain
out to our west throughout the day. VFR conditions are expected at
all the terminals today with southeast winds picking up during the
mid-morning hours. The pressure gradient is expected to increase as
a deep upper low continues to strengthen over the Plains. Southeast
winds of 10-15 mph with gusts up to 20 mph will be possible later
this afternoon.
A few waves of low pressure will move up along the frontal boundary
producing a few rounds of showers later today. The vast majority of
this activity will stay west of KBWG and KSDF this afternoon.
Coverage still looks rather sparse enough to preclude mention in
this TAF forecast at the moment.
&&
.Hydrology...
Issued at 300 PM EDT Thu May 2 2013
An upper air disturbance is forecast to move across the region this
weekend. This will result in moderate to heavy rainfall over
southern Kentucky. Between Friday afternoon and Sunday morning
between one and inch inches could fall with the heaviest amounts
near Bowling Green.
This area recently had minor flooding and this new rain could result
in a new round of flooding in the middle of the Green River Basin.
Residents with livestock or equipment in flood prone areas should
watch water levels closely this weekend.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Updates..........MJ/RJS
Short Term.......MJ
Long Term........EER
Aviation.........MJ
Hydrology........CMC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
931 AM EDT FRI MAY 3 2013
.SYNOPSIS...
ISSUED AT 340 AM EDT FRI MAY 3 2013
IT WILL BE MILD TODAY WITH SCATTERED AFTERNOON SHOWERS AND A FEW
THUNDERSTORMS MAINLY WEST OF A LINE FROM KALAMAZOO TO GRAND RAPIDS
AND BIG RAPIDS. DRY AND MILD WEATHER IS ANTICIPATED THROUGH THE
WEEKEND AND FOR MOST OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 932 AM EDT FRI MAY 3 2013
UPDATED FORECAST TO ACCOUNT FOR RAIN SHOWERS CURRENTLY OVER FAR
SW CWA. HAVE GENERALLY RAISED POPS NEAR THE LAKESHORE INTO THE
AFTERNOON. LATEST HRRR GUIDANCE SUGGESTS THAT AREA OF PRECIPITATION
OVER CENTRAL IN WILL MOVE NORTH...REACHING OUR SOUTHERN CWA BY
THIS EVENING. WILL MONITOR THIS AND MAY BE RAISING POPS SOUTH OF
I-96 LATER TODAY IF THESE TRENDS CONTINUE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY AFTERNOON)
ISSUED AT 340 AM EDT FRI MAY 3 2013
OUR PRIMARY SHORT TERM FCST CHALLENGE IS TO DETERMINE PROBABILITIES
FOR SCATTERED SHOWERS/TSTORMS TODAY. AS WAS THE CASE YESTERDAY
AFTERNOON WE EXPECT SFC CONVERGENCE FROM AN INVERTED SFC TROF AND
THE LAKE BREEZE TO TRIGGER DEVELOPMENT OF SHOWERS AND A FEW STORMS
THIS AFTERNOON... WITH THE RELATIVELY BEST CHC FOR THOSE WEST OF
US-131 AS SUGGESTED BY LATEST 00Z 4KM WRF-NMM SIM Z GUIDANCE. MAX
TEMPS WILL REACH THE LOW TO MID 70S EXCEPT SIGNIFICANTLY COOLER
RIGHT ALONG THE LAKE MI SHORELINE.
DRY AND SEASONABLY MILD WX IS THEN EXPECTED TONIGHT THROUGH SUNDAY
AS THE UPPER RIDGE AXIS TAKES HOLD AND UPPER LOW DRIFTS FURTHER SE
INTO THE SOUTHEASTERN UNITED STATES. MAX TEMPS THIS WEEKEND SHOULD
AGAIN REACH THE LOW TO MID 70S. THE EASTERLY WINDS WILL LIKELY NOT
BE STRONG ENOUGH TO PRECLUDE LAKE BREEZE DEVELOPMENT SATURDAY AND
SUNDAY... SO LOCATIONS RIGHT ALONG LAKE MI SHOULD AGAIN BE COOLER.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 340 AM EDT FRI MAY 3 2013
LOOKS LIKE A QUIET WEATHER PATTERN IN THE EXTENDED AS THE UPPER LOW
TRACKS WELL SOUTH OF THE GREAT LAKES AND DRY EAST FLOW DOMINATES.
ADDED SLIGHT CHANCE POPS FOR THURSDAY AS WEAKER...NORTHERN CUT OFF
LOW FINALLY MOVES EAST AND OVER LOWER MICHIGAN. THIS SHOULD BE
MOISTURE STARVED SINCE IT HAS LITTLE OR NO GULF MOISTURE TO WORK
WITH.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 751 AM EDT FRI MAY 3 2013
VFR SHOULD PREVAIL MOST OF THE DAY BUT AREAS OF MVFR IN SHOWERS
AND THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND INTO THE
EVENING. LEFT THIS OUT OF THE FORECAST SINCE THE COVERAGE IS
EXPECTED TO BE LOW...BUT PROBABLY GREATER THAN YESTERDAY. WINDS
WILL BE AOB 10 KNOTS FROM THE EAST OR SOUTHEAST.
&&
.MARINE...
ISSUED AT 340 AM EDT FRI MAY 3 2013
WE WILL ALLOW THE SCA TO EXPIRE EARLY THIS MORNING. WAVE HEIGHTS OF
2 TO 4 FEET ARE ANTICIPATED TODAY BUT WAVES AND WINDS WILL STAY BELOW
SCA CRITERIA. MINIMAL WAVE ACTION IS ANTICIPATED THIS WEEKEND WITH
OFFSHORE WINDS.
&&
.FIRE WEATHER...
ISSUED AT 340 AM EDT FRI MAY 3 2013
A FEW SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY. AFTER TODAY DRY
AND MILD WEATHER IS EXPECTED THIS WEEKEND THROUGH MOST OF NEXT WEEK
KEEPING FUEL MOISTURE RATHER LOW.
&&
.HYDROLOGY...
ISSUED AT 340 AM EDT FRI MAY 3 2013
ANY PRECIPITATION TODAY FROM SCATTERED SHOWERS AND A FEW STORMS WILL
BE QUITE LIGHT. DRY WEATHER IS EXPECTED THIS WEEKEND THROUGH MOST OF
NEXT WEEK. THEREFORE THERE ARE NO SIGNIFICANT HYDRO CONCERNS AT THIS
TIME THAT WOULD AFFECT MAINSTEM RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...TJT
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...OSTUNO
FIRE WEATHER...LAURENS
HYDROLOGY...LAURENS
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS DULUTH MN
1025 AM CDT FRI MAY 3 2013
.UPDATE...
HAVE EXTENDED THE WINTER WEATHER ADVISORY FOR FREEZING RAIN OVER
NORTHERN WISCONSIN /EXCEPT PRICE COUNTY/ THROUGH 1000 PM THIS
EVENING...POSSIBLY NEEDING TO BE EXTENDED FURTHER. THE 12Z
NAM/DLHWRF BOTH SHOW SFC TEMPS REMAIN BELOW FREEZING OVER THE
ADVISORY AREA THROUGH AT LEAST MIDNIGHT. MEANWHILE...AN S-SE H85
FLOW WILL CONTINUE TO WARM MID LEVELS THROUGH THE
DAY...DIMINISHING ANY LINGERING SNOW AND PROMOTING FREEZING RAIN
THIS AFTERNOON/TONIGHT.
HAVE INTRODUCED MENTION OF FREEZING RAIN TO MN ARROWHEAD ZONES
THIS AFTERNOON AND EVENING WHERE H80-H85 LAYER TEMPS WARM A FEW
DEGREES ABOVE 0 C...WHILE SFC READINGS REMAIN SUB-FREEZING. WE
WILL CLOSELY MONITOR THIS AREA FOR ICE ACCUM POTENTIAL...AND AN
ADVISORY MAY BE NEEDED THIS AFTERNOON/TONIGHT FOR LAKE COOK
COUNTIES.
&&
.PREV DISCUSSION... /ISSUED 644 AM CDT FRI MAY 3 2013/
AVIATION...12Z TAFS
WAA AND AN INVERTED TROUGH WERE CAUSING SNOW...WITH A WINTRY MIX IN
SPOTS OVER NORTHWEST WISCONSIN. MVFR WITH SOME SPOTTY IFR CEILINGS
COVERED NORTHWEST WISCONSIN. OVERALL...MVFR OR EVEN SOME IFR
CONDITIONS SHOULD SPREAD WEST AND NORTH THROUGH THE DAY INTO
TONIGHT. SNOW...OR A WINTRY MIX WILL ALSO SPREAD WEST AND NORTH
TODAY. BOUNDARY LAYER TEMPS WILL THEN WARM AND RAIN WILL BECOME
MORE WIDESPREAD. FREEZING RAIN WILL THEN BE POSSIBLE AGAIN LATER
TONIGHT AS SURFACE TEMPS COOL.
PREV DISCUSSION... /ISSUED 408 AM CDT FRI MAY 3 2013/
SHORT TERM...TODAY THROUGH SATURDAY.
AT 4 AM...IT WAS FAIRLY QUIET ACROSS THE NORTHLAND. THERE WAS SOME
LIGHT SNOW ACROSS NW WI...AND REPORTS JUST OUTSIDE OF THE CWA OF
SOME LIGHT FREEZING DRIZZLE. TEMPERATURES RANGED FROM THE 20S IN
NE MN TO AROUND 30 IN NW WI.
THE NEXT MAIN WAVE OF PRECIPITATION WAS QUICKLY STREAMING
NORTHWARD THROUGH THE PLAINS. WE SHOULD SEE AN INCREASE
THROUGHOUT THE MORNING ACROSS WESTERN WISCONSIN. DEFINITELY SOME
PTYPE ISSUES...AND A THOROUGH ASSESSMENT OF THE FORECAST SOUNDINGS
SHOW SOME PRETTY SIGNIFICANT DIFFERENCES AMONG THE MODELS. JUST A
FEW DEGREES DIFFERENCE IN THE WARM LAYER WILL MEAN A CHANGE FROM
FREEZING RAIN OR RAIN...TO SLEET AND/OR SNOW.
FOR TODAY...HAVE RAISED POPS A BIT THROUGHOUT THE DAY...FIRST WITH
LIKELY POPS IN THE EASTERN 1/3 OF THE CWA...AND THEN SPREADING IT
NORTHWARD AND WESTWARD AS THE MORNING WEARS ON. NAM BUFR SOUNDINGS
AND THE HRRR FORECAST PTYPE INDICATE THAT A MIXTURE COULD LAST
INTO THE AFTERNOON...AND THERE MAY BE SOME SLEET AS WELL.
FORECAST LAYER THICKNESS VALUES ALSO INDICATE SOME POTENTIAL FOR
THIS TO LAST INTO THE AFTERNOON AND EVEN TONIGHT. WILL EXTEND THE
ADVISORY TIME THROUGH NOON WITH THE CAVEAT THAT SOME AREAS MAY
NEED TO BE EXTENDED INTO THE AFTERNOON.
HAVE INCREASED POPS CONSIDERABLY TONIGHT AND ON SATURDAY...WITH
GENERALLY RAIN DURING THE EVENING AND RAIN AND/OR FREEZING RAIN
AFTER MIDNIGHT. IN GENERAL...WE SHOULD SEE MAINLY RAIN ON
SATURDAY. TEMPS WILL BE TRICKY DUE TO THE CLOUDS AND EXPECTED
PRECIPITATION.
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
A TROUGH OF LOW PRESSURE AND BAROCLINIC ZONE IS EVIDENT SATURDAY
NIGHT...WEAKENING SUNDAY. THIS WILL LEAD TO A CHANCE FOR RAIN OVER
MUCH OF THE CWA SATURDAY NIGHT...DIMINISHING FROM NORTH TO SOUTH
SUNDAY. RIDGING WILL TAKE OVER MONDAY INTO MONDAY NIGHT AND LEAD TO
A DRY PERIOD.
CONFIDENCE DIMINISHES MONDAY NIGHT INTO AT LEAST MID WEEK...AS THE
ECMWF BRINGS IN A SHORTWAVE AND SUPPORTS THE CHANCE FOR SHOWERS
TUESDAY/WEDNESDAY. WE FOLLOWED CLOSER TO THIS SOLUTION DURING THAT
PERIOD.
THE MODELS THEN HAVE A FASTER WNW FLOW OVER FAR NORTHERN MN/SOUTHERN
CANADA BY LATE IN THE WEEK WITH A CONTINUED CHANCE FOR RAIN WITH
WEAK LOW PRESSURE AT THE SURFACE. WE HAVE POPS CONTINUING THROUGH
THE REST OF THE PERIOD...ALTHOUGH WERE NOT OVERLY IMPRESSED WITH THE
FORCING AND EXPECTED PRECIPITATION AMOUNTS.
TEMPERATURES WILL BE A BIT BELOW NORMAL SUNDAY...RISING INTO THE
SIXTIES MONDAY THROUGH THE END OF THE WEEK.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY WILL SLOW
THE MELT...BUT TEMPS WILL START TO WARM THIS WEEKEND INTO NEXT
WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 37 32 40 36 / 80 80 60 50
INL 47 29 51 33 / 10 20 10 10
BRD 49 34 45 38 / 10 60 60 40
HYR 33 32 44 34 / 90 80 60 30
ASX 34 32 39 33 / 90 80 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 10 PM CDT THIS EVENING FOR
WIZ002>004-007-008.
WINTER WEATHER ADVISORY UNTIL NOON CDT TODAY FOR WIZ009.
LS...SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-143>148.
&&
$$
SHORT TERM...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
644 AM CDT FRI MAY 3 2013
.AVIATION...12Z TAFS
WAA AND AN INVERTED TROUGH WERE CAUSING SNOW...WITH A WINTRY MIX IN
SPOTS OVER NORTHWEST WISCONSIN. MVFR WITH SOME SPOTTY IFR CEILINGS
COVERED NORTHWEST WISCONSIN. OVERALL...MVFR OR EVEN SOME IFR
CONDITIONS SHOULD SPREAD WEST AND NORTH THROUGH THE DAY INTO
TONIGHT. SNOW...OR A WINTRY MIX WILL ALSO SPREAD WEST AND NORTH
TODAY. BOUNDARY LAYER TEMPS WILL THEN WARM AND RAIN WILL BECOME
MORE WIDESPREAD. FREEZING RAIN WILL THEN BE POSSIBLE AGAIN LATER
TONIGHT AS SURFACE TEMPS COOL.
&&
.PREV DISCUSSION... /ISSUED 408 AM CDT FRI MAY 3 2013/
SHORT TERM...TODAY THROUGH SATURDAY.
AT 4 AM...IT WAS FAIRLY QUIET ACROSS THE NORTHLAND. THERE WAS SOME
LIGHT SNOW ACROSS NW WI...AND REPORTS JUST OUTSIDE OF THE CWA OF
SOME LIGHT FREEZING DRIZZLE. TEMPERATURES RANGED FROM THE 20S IN
NE MN TO AROUND 30 IN NW WI.
THE NEXT MAIN WAVE OF PRECIPITATION WAS QUICKLY STREAMING
NORTHWARD THROUGH THE PLAINS. WE SHOULD SEE AN INCREASE
THROUGHOUT THE MORNING ACROSS WESTERN WISCONSIN. DEFINITELY SOME
PTYPE ISSUES...AND A THOROUGH ASSESSMENT OF THE FORECAST SOUNDINGS
SHOW SOME PRETTY SIGNIFICANT DIFFERENCES AMONG THE MODELS. JUST A
FEW DEGREES DIFFERENCE IN THE WARM LAYER WILL MEAN A CHANGE FROM
FREEZING RAIN OR RAIN...TO SLEET AND/OR SNOW.
FOR TODAY...HAVE RAISED POPS A BIT THROUGHOUT THE DAY...FIRST WITH
LIKELY POPS IN THE EASTERN 1/3 OF THE CWA...AND THEN SPREADING IT
NORTHWARD AND WESTWARD AS THE MORNING WEARS ON. NAM BUFR SOUNDINGS
AND THE HRRR FORECAST PTYPE INDICATE THAT A MIXTURE COULD LAST
INTO THE AFTERNOON...AND THERE MAY BE SOME SLEET AS WELL.
FORECAST LAYER THICKNESS VALUES ALSO INDICATE SOME POTENTIAL FOR
THIS TO LAST INTO THE AFTERNOON AND EVEN TONIGHT. WILL EXTEND THE
ADVISORY TIME THROUGH NOON WITH THE CAVEAT THAT SOME AREAS MAY
NEED TO BE EXTENDED INTO THE AFTERNOON.
HAVE INCREASED POPS CONSIDERABLY TONIGHT AND ON SATURDAY...WITH
GENERALLY RAIN DURING THE EVENING AND RAIN AND/OR FREEZING RAIN
AFTER MIDNIGHT. IN GENERAL...WE SHOULD SEE MAINLY RAIN ON
SATURDAY. TEMPS WILL BE TRICKY DUE TO THE CLOUDS AND EXPECTED
PRECIPITATION.
LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
A TROUGH OF LOW PRESSURE AND BAROCLINIC ZONE IS EVIDENT SATURDAY
NIGHT...WEAKENING SUNDAY. THIS WILL LEAD TO A CHANCE FOR RAIN OVER
MUCH OF THE CWA SATURDAY NIGHT...DIMINISHING FROM NORTH TO SOUTH
SUNDAY. RIDGING WILL TAKE OVER MONDAY INTO MONDAY NIGHT AND LEAD TO
A DRY PERIOD.
CONFIDENCE DIMINISHES MONDAY NIGHT INTO AT LEAST MID WEEK...AS THE
ECMWF BRINGS IN A SHORTWAVE AND SUPPORTS THE CHANCE FOR SHOWERS
TUESDAY/WEDNESDAY. WE FOLLOWED CLOSER TO THIS SOLUTION DURING THAT
PERIOD.
THE MODELS THEN HAVE A FASTER WNW FLOW OVER FAR NORTHERN MN/SOUTHERN
CANADA BY LATE IN THE WEEK WITH A CONTINUED CHANCE FOR RAIN WITH
WEAK LOW PRESSURE AT THE SURFACE. WE HAVE POPS CONTINUING THROUGH
THE REST OF THE PERIOD...ALTHOUGH WERE NOT OVERLY IMPRESSED WITH THE
FORCING AND EXPECTED PRECIPITATION AMOUNTS.
TEMPERATURES WILL BE A BIT BELOW NORMAL SUNDAY...RISING INTO THE
SIXTIES MONDAY THROUGH THE END OF THE WEEK.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY WILL SLOW
THE MELT...BUT TEMPS WILL START TO WARM THIS WEEKEND INTO NEXT
WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 40 32 40 36 / 40 80 60 50
INL 47 29 51 33 / 10 20 10 10
BRD 49 34 45 38 / 10 60 60 40
HYR 42 32 44 34 / 80 80 60 30
ASX 37 32 39 33 / 70 80 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL NOON CDT TODAY FOR WIZ002>004-
007>009.
LS...SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-143>148.
&&
$$
SHORT TERM...DAP
LONG TERM....MELDE
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
950 AM EDT FRI MAY 3 2013
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER NEW ENGLAND THROUGH THE WEEKEND
THEN BEGIN TO WEAKEN EARLY NEXT WEEK. LOW PRESSURE EXTENDING UP
THE MISSISSIPPI VALLEY TO LAKE MICHIGAN WILL REMAIN STATIONARY
INTO SATURDAY THEN SLOWLY MOVE EAST THROUGH THE LOWER TENNESSEE
VALLEY.
&&
.NEAR TERM /THROUGH TONIGHT/...
ONLY MINOR CHANGES PLANNED FOR THE FORECAST. THE 12Z SOUNDINGS SHOW
A SHARP GRADIENT IN MOISTURE ACROSS THE REGION WITH PRECIP WATER AT
PIT ONLY .13 INCH TO .82 INCH AT ILN. THE HRRR ACKNOWLEDGES THIS
DRY AIR OVER THE CENTRAL APPALACHIANS AND ADVECTS IT NORTHWESTWARD
ACROSS THE EASTERN 2/3 OF THE FORECAST AREA THIS AFTERNOON. WILL
LOWER DEWPOINTS IN THE 30S AND RAISE MAX TEMPERATURES A FEW
DEGREES TO SUPPORT THE 12Z SOUNDING AT PIT.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY NIGHT/...
THE SHORT TERM FORECAST DEPENDS ON THE EVOLUTION OF THE UPPER LOW
AS IT FORMS TODAY IN THE AR/MO REGION. CURRENT GFS/NAM/SREF RUNS
FAIRLY AGREEABLE IN KEEPING THE LOW IN AR THROUGH SATURDAY NIGHT
BEFORE DRIVING IT SLOWLY EAST ACROSS AL AND GA. MEANWHILE HIGH
PRESSURE ALOFT AND AT THE SURFACE WILL EXTEND INTO THE AREA FROM
THE E/NE WITH DRY AIR CONTINUING TO MOVE ACROSS THE AREA. BASED ON
THIS KEPT THE FORECAST DRY THROUGH THE ENTIRE SHORT TERM PERIOD
WITH FAIR SKIES EXPECTED MUCH OF THE TIME. TEMPS SHOULD REMAIN
SEASONAL TO A FEW DEGREES ABOVE.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
ONLY DAY THAT HAS ANY CHANCE OF PRECIPITATION IS TUESDAY...AND THAT
MAY NOT PAN OUT. MORE CONSISTENCY WITH MODELS MAINTAINING HIGH
PRESSURE OVER THE AREA AND SHIFTING THE CUTOFF LOW EAST ACROSS THE
TN VALLEY. CLOUD SHIELD WILL LIKELY REACH TO THE LOCAL AREA...BUT
SHOWERS MAY NOT. WILL CONTINUE THE LOW PRECIP CHANCES...WITH NO
PRECIP MENTIONED FOR WEDNESDAY AND THURSDAY. TEMPERATURES SLIGHTLY
ABOVE NORMAL.
&&
.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL CONTINUE THROUGH TONIGHT. MOST LOCATIONS WILL
ONLY SEE VARIABLE AMOUNTS OF HIGH LEVEL CLOUD COVER. EXPECT SE
WINDS TO CONTINUE WITH SOME GUSTS AROUND 20 KNOTS FOR MOST
LOCATIONS BY FRIDAY AFTERNOON. LAKE BREEZE POSSIBLE AT KERI...NOT
AS LIKELY FOR KCLE. NO CHANGES.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE BY MONDAY.
&&
.MARINE...
HIGH PRESSURE TO THE EAST OF THE LAKE WILL CONTINUE TO BLOCK THE
ADVANCEMENT OF LOW PRESSURE ACROSS THE WESTERN LAKES/MIDWEST. THAT
SYSTEM WILL EVENTUALLY PASS SOUTH OF LAKE ERIE...LIKELY ACROSS THE
TN VALLEY EARLY NEXT WEEK. THIS WILL LEAVE HIGH PRESSURE AS THE MAIN
INFLUENCE FOR LAKE ERIE. CAN EXPECT DAILY ONSHORE/LAKE BREEZE FLOW
FOR MOST OF THE AFTERNOONS...THE SOUTHEAST FLOW AT NIGHT BECOMING
MORE NORTHEASTERLY. BY MIDWEEK HIGH PRESSURE BUILDS OVER THE WESTERN
LAKES AND THE FLOW ACROSS LAKE ERIE WILL BECOME MORE NORTHERLY...BUT
STILL REMAIN LIGHT.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TK
NEAR TERM...LAPLANTE
SHORT TERM...TK
LONG TERM...OUDEMAN
AVIATION...OUDEMAN
MARINE...OUDEMAN
AREA FORECAST DISCUSSION...UPDATED
NWS MORRISTOWN TN
938 AM EDT FRI MAY 3 2013
.DISCUSSION...
NO CHANGES ARE NEEDED TO THE FORECAST THIS MORNING. A SE FLOW OF
MOISTURE OFF THE ATLANTIC IS BRINGING BROKEN CLOUDS TO SOUTHERN
AREAS...WHILE DOWNSLOPE EFFECTS ARE PROVIDING MOSTLY SUNNY SKIES IN
THE CENTRAL AND SOUTHERN TN VALLEY. THE RUC AND SREF SHOW LIGHT QPF
COMING INTO SOUTHERN SECTIONS LATE IN THE AFTERNOON...AND THE
CURRENT FORECAST OF LOW CHANCE POPS IN THAT AREA LOOKS GOOD. TEMPS
AND DEWPOINTS APPEAR TO BE IN LINE WITH OBS.
&&
.MRX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
TN...NONE.
VA...NONE.
&&
$$
DGS
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1132 AM MDT FRI MAY 3 2013
.UPDATE...
ISSUED AT 853 AM MDT FRI MAY 3 2013
UPDATED FORECAST TO TAKE DOWN THE FREEZE WARNING FOR THE REMAINDER
OF THIS MORNING AS TEMPERATURES CONTINUE TO RISE ABOVE FREEZING.
THERE IS STILL THE POTENTIAL FOR ANOTHER FROST OR FREEZE AGAIN
TONIGHT SO CURRENT FREEZE WATCH FOR TONIGHT WILL REMAIN IN EFFECT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 300 AM MDT FRI MAY 3 2013
CURRENTLY...CLEAR SKIES WITH NORTHERLY FLOW ALOFT AS THE UPPER
TROUGH SITS TO THE EAST OF COLORADO OVER KS AND NE...AS PER LATEST
SATELLITE IMAGERY AND H5 RAP ANALYSIS. WIDESPREAD BELOW FREEZING
TEMPS FOR THE EASTERN CO PLAINS AS OF 3 AM.
TODAY AND TONIGHT...NOT A LOT TO ADD TO THE ONGOING FORECAST PACKAGE
IN THE SHORT TERM. THE UPPER TROUGH TO THE EAST IS EXPECTED TO
STRENGTHEN AS IT EJECTS TO THE SE AWAY FROM CO...RELAXING THE WINDS
ALOFT FOR THE STATE. SUNNY TO MOSTLY SUNNY SKIES ARE EXPECTED
TODAY...WITH A NICE REBOUND FOR TEMPS INTO THE UPPER 50S TO MID 60S
FOR MOST LOCATIONS TODAY. LIGHT WINDS AND CLEAR SKIES TONIGHT WILL
PRODUCE ONE MORE NIGHT AND SUB-FREEZING TEMPS...AND CURRENT FREEZE
WATCH LOOKS GOOD. DECIDED TO HOLD OFF ON UPGRADING AT THIS
TIME...AND TO AVOID CONFUSION OPTED TO LET CURRENT WARNING RUN THE
COURSE...THEN AT EXPIRATION THE WATCH CAN BE UPGRADED. MOORE
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 300 AM MDT FRI MAY 3 2013
...WETTER PATTERN POSSIBLE THIS PERIOD...
SIMULATIONS IN RATHER GOOD AGREEMENT GIVEN THE RATHER WEAK FLOW
REGIME WHICH WILL BE OVER THE WESTERN PART OF THE CONUS THIS
PERIOD. AT THE BEGINNING OF THIS PD (SAT 12Z)...A WELL ESTABLISHED
CUTOFF LOW WILL BE LOCATED IN THE VICINITY OF MISSOURI WHILE A
WEAKER CLOSED LOW WILL BE DEVELOPING OVER THE S IDAHO REGION. WEAK
RIDGING AND OVERALL WEAK MIDLVL FLOW WILL BE OVER THE FCST AREA.
AS THE WEEKEND PROGRESSES...THE LOW OVER MISSOURI WILL SLOWLY MOVE
EAST WHILE THE UPPER LOW OVER IDAHO RETROGRADES OVER N CALIF. THIS
WILL ALLOW FOR A SMALL MIDLVL RIDGE TO BUILD OVER THE FCST AREA.
GIVEN THIS PATTERN...I EXPECT IT WILL BE MAINLY DRY OVER THE
REGION. A FEW SCTD AFTERNOON AND EVENING TSRA WILL BE POSSIBLE
OVER THE CONTDVD AND AN ISOLATED STORM OR TWO WILL BE POSSIBLE
OVER THE S MTNS/PIKES PEAK REGION. DAYTIME TEMPS WILL BE PLEASANT
WITH MAINLY 60S ACROSS THE PLAINS AND VALLEYS.
DURING THE MONDAY TIMEFRAME...A SHORTWAVE WILL EJECT OUT OF THE
CALIF LOW AND MOVE ACROSS THE REGION. I EXPECT WE WILL SEE
INCREASING CHANCES OF SHOWER OVER THE MTNS WITH ISOLATED SHOWERS
BECOMING POSSIBLE OVER THE PLAINS LATE IN THE DAY. MAX TEMPS MONDAY
WILL BE A FEW DEGREES WARMER THAN THE WEEKENDS HIGHS. SHEAR WILL BE
INCREASING MONDAY (ALTHOUGH NOT ALL THAT STRONG)...SO WE MAY SEE A
BIT MORE ORGANIZED CONVECTION ON THIS DAY ON THE PLAINS.
TUESDAY...CALIF LOW STARTS TO MOVE EAST AND SIMULATIONS HINT AT A
DRY SLOT AFFECTING THE S TIER OF THE CWA. THIS SHOULD BRING A
DECREASING THREAT OF SHOWERS TO THE REGION AND ALLOW FOR TEMPS TO
RISE INTO THE MID 70S ACROSS THE PLAINS WITH 60S VALLEYS.
WEDNESDAY IS WHEN THE MAIN LOW MOVES OVER THE STATE...AND THIS IS
THE DAY WE SHOULD SEE THE MOST ACTIVE WX. THERE IS NOT MUCH COLD AIR
WITH THIS SYSTEM SO ALL PRECIP (EXCEPT OVER THE HIGHEST TRRN) SHOULD
BE LIQUID. SHEAR IS FCST TO BE RATHER IMPRESSIVE (ESPECIALLY GFS) OVER
THE FAR E PLAINS AND IT IS POSSIBLE WE MAY SEE OUR FIRST SEVERE WX
THREAT OVER THE FCST AREA. THERE WILL ALSO BE A GOOD CHANCE OF
PRECIP OVER THE ENTIRE AREA GIVEN THE EXPECTED INSTABILITY AND
FORCING. FOR NOW I HAVE POPS IN THE 20-40% RANGE...BUT THESE VALUES
MAY NEED TO BE INCREASED IF MODELS CONTINUE TO SHOW THIS SCENARIO.
MAX TEMPS THIS DAY WILL BE COOLER GIVEN THE LIKELY INCREASED CLOUD
COVER OVER THE FCST AREA.
WED NITE THROUGH THU THE WEAK UPPER LOW MOVES VERY LITTLE AND WE
SHOULD SEE A CONTINUED THREAT OF MUCH NEED PRECIP OVER THE FCST
AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1122 AM MDT FRI MAY 3 2013
VFR CONDITIONS ARE EXPECTED AT KPUB...KCOS...AND KALS THROUGH 18Z
SATURDAY WITH ONLY A FEW HIGH CLOUDS MOVING ACROSS SOUTHEASTERN
COLORADO BY 20Z. -PJC
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE TONIGHT THROUGH SATURDAY MORNING FOR
COZ084>089-093>099.
&&
$$
UPDATE...KT
SHORT TERM...MOORE
LONG TERM...HODANISH
AVIATION...PJC
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1018 AM MDT FRI MAY 3 2013
.UPDATE...
&&
.SHORT TERM...ONGOING FORECASTS LOOK ON TRACK. HIGH PRESSURE WILL
CONTINUE TO BUILD ACROSS COLORADO DESPITE THE NORTHERLY FLOW
ALOFT. WARMUP TO CONTINUE WITH HIGHS ACROSS NORTHEAST COLORADO
AROUND 60 DEGREES. EXPECTED FORECAST HIGHS MAY NEED TO BE
INCREASED A FEW DEGREES AS CURRENT TEMPERATURES ALREADY IN THE
40S ACROSS PLAINS. SOME INCREASE IN HIGH LEVEL CLOUDS AND WEAK
NORTHERLY SURGE MAY SLOW WARMUP. WILL SEE HOW THINGS TRANSPIRE
BEFORE MAKING ANY ADJUSTMENTS.
.AVIATION...CURRENT TAF TRENDS LOOK REASONABLE. WEAK NORTHERLY SURGE
STILL EXPECTED AROUND 18Z...AS NOTED BY LATEST RAP AND HRRR...WITH
THE TREND TOWARD EASTERLY BY 00Z THEN SOUTHEAST DURING THE EVENING.
VFR...
&&
.HYDROLOGY...
&&
.PREV DISCUSSION... /ISSUED 406 AM MDT FRI MAY 3 2013/
SHORT TERM...NORTHERLY FLOW ALOFT WILL PREVAIL TODAY AS AN UPPER
LEVEL LOW SPINS OVER THE CENTRAL AND SOUTHERN PLAINS. FLOW ALOFT
WILL NORTHWESTERLY AS A RIDGE STARTS TO FORM DUE TO A TROUGH MOVING
SOUTHWEST ACROSS THE NORTHERN ROCKIES.
FOR TODAY...AIRMASS CONTINUES TO RECOVER FROM THE COLD BLAST A
COUPLE OF DAYS AGO. HIGHS WILL BE NEAR 60 DEGREES ACROSS NORTHEAST
COLORADO. NORTH TO NORTHEAST WINDS WILL DEVELOP THIS AFTERNOON AS A
SURFACE HIGH RESIDES OVER THE NORTHERN PLAINS. AS THIS HIGH SINKS
SOUTH OVERNIGHT...IT WILL PUSH SLIGHTLY COOLER AIR INTO THE AREA FOR
SATURDAY. BECAUSE OF THIS SURFACE HIGH SINKING SOUTH...THE NORMAL
SOUTHERLY DRAINAGE WINDS WILL HAVE A HARD TIME DEVELOPING TONIGHT.
OVERNIGHT LOWS WILL CONTINUE TO BE ON THE COOL SIDE FOR THIS TIME OF
YEAR WITH READINGS AROUND 32 DEGREES.
LONG TERM...CONTORTED JET STREAM PATTERN TAKES SHAPE OVER THE WRN
CONUS OVER THE WEEKEND. BY SATURDAY...100+ KT JET DIVING SOUTH OUT
OF WESTERN CANADA CARVES OUT A STRONG POSITIVELY TILTED UPPER LEVEL
TROUGH OVER THE PACIFIC NORTHWEST/NORTHERN ROCKIES. AS THIS IS GOING
ON...NEARLY ZONAL FLOW ALOFT SETS UP OVER COLORADO WITH A SHORTWAVE
RIDGE FORMING TO OUR SOUTH. MEANWHILE POST-FRONTAL EAST-NORTHEAST
LOW-LEVEL FLOW COUPLED WITH DIURNAL HEATING APPEARS TO PRODUCE LOW
TOP CONVECTION OVER AND NEAR THE FRONT RANGE MTNS SATURDAY
AFTERNOON. ANY PRECIP SHOULD BE LIGHT ACCORDING TO THE NAM AND GFS
AND MOST OF THAT CONFINED TO THE HIGHER ELEVATIONS. BY SATURDAY
EVENING COULD SEE SOME ENHANCEMENT IN THIS PRECIP WITH LOWERING
CLOUD BASES GENERALLY ALONG AND WEST OF THE FRONT RANGE...WITH A
WEAK MID-LEVEL DISTURBANCE MOVING UP FROM THE FOUR CORNERS. GFS IS A
BIT MORE AMBITIOUS WITH ITS MOISTURE PROFILE AND THE AMOUNT OF
PRECIP IT PRODUCES. STILL...PRECIP AMOUNTS SHOULD BE ON THE LOW
SIDE. EXCEPT FOR A FEW SHOWERS DRIFTING OVR THE I-25 URBAN CORRIDOR
DURING THE EVENING...DO NOT SEE ANY PRECIP FARTHER OUT ON THE
PLAINS.
ON SUNDAY...AS THE UPPER RIDGE TO OUR SOUTH CONTINUES TO AMPLIFY
..SO DOES THE SOUTHWEST FLOW CARRYING MID AND HIGH LEVEL MOISTURE
UP FROM THE DESERT SOUTHWEST. THIS INCREASE IN FLOW IS IN RESPONSE
TO THE STRONG JET SPINNING UP A DEEP CUTOFF LOW OFF THE CALIFORNIA
COAST. THE SHIFT TO A MORE SOUTHERLY FLOW ALOFT AND A SOUTHEASTERLY
LOW LEVEL FLOW ON THE PLAINS HELPS TO DRAWS MORE LOW AND MID-LEVEL
MOISTURE UP INTO THE AREA RESULTING IN MORE CLOUDS MAINLY AT AND
ABOVE MTN TOP LEVEL AND A SLIGHTLY BETTER CHANCE OF WETTING PRECIP
FOR THE HIGH COUNTRY...AS WELL AS A SLIGHT CHANCE OF RAIN SHOWERS
FOR THE URBAN CORRIDOR AND PALMER DIVIDE AREAS BY EVENING.
TEMPERATURES IN THE 50S ON THE PLAIN SATURDAY ARE EXPECTED TO THE
LOWER 60S ON SUNDAY. HIGH COUNTRY TEMPERATURE ABOUT THE SAME BOTH
DAYS..IN THE 40S AND LOWER 50S. CLOUD COVER AND COOL TEMPERATURES
WILL KEEP SNOWMELT RUNOFF IN THE HIGH COUNTRY IN CHECK.
BY MONDAY...MODELS SHOW A ZONAL JET STREAM SNAKING ALONG THE U.S.
MEXICO BORDER WITH COLORADO UNDER A MUCH WEAKER DIFLUENT SOUTHWEST
FLOW ALOFT. LOW-LEVEL FLOW EAST OF THE MTNS REMAINS SOUTHEASTERLY.
THROUGH THE DAY MODELS INDICATE YET ANOTHER EVEN STRONGER SHORTWAVE
TROUGH ROTATING UP FROM THE SOUTHWEST WITHIN THE BROAD CIRCULATION
AROUND THE WEST COAST CUTOFF LOW. WOULD EXPECT TO SEE SHOWERS ON THE
INCREASE IN THE HIGH COUNTRY FROM SOUTH TO NORTH ON MONDAY AS THE
SHORTWAVE TROUGH SWINGS NORTHWARD ACROSS THE REGION. SNOW LEVEL
SHOULD REMAIN FAIRLY HIGH POSSIBLY UP AROUND 10500 OR 11000 FT WITH
WARM ADVECTION. BY AFTERNOON WITH STEEP MID-LEVEL LAPSE RATES...
ISOLATED T-STORMS ALSO A POSSIBILITY OVER THE HIGH TERRAIN. LATEST
GUIDANCE SHOWS THE SHORT WAVE ENERGY AND MOISTURE PASSING OVER THE
NORTHEAST PLAINS DURING THE EVENING. NOT SURE ABOUT ANY THUNDER. LOW
POPS LOOK GOOD THERE. TEMPERATURES ON MONDAY WARM 1-2 DEG C FROM THE
DAY BEFORE.
TUESDAY AND BEYOND...PERIOD STARTS OUT DRY TUESDAY MORNING WITH WEAK
DOWNWARD MOTION IN THE WAKE OF PASSING SHORTWAVE. FROM
THERE...MODELS SHOW A GENERAL INCREASE IN MOISTURE AND LARGE SCALE
LIFT WITH THE WEST COAST CYCLONE FINALLY MAKING ITS MOVE INLAND
ACROSS THE GREAT BASIN. MODELS EVOLVE THIS CLOSED LOW INTO A BROAD
LOW PRESSURE TROUGH WHICH SLOWLY MIGRATES EASTWARD ACROSS THE CENTRAL
AND SOUTHERN ROCKY MTN REGIONS MIDWEEK. THIS WOULD KEEP TEMPERATURE
AT OR BELOW AVERAGE AND THE WEATHER UNSETTLED WITH A CHANCE OF
SHOWERS STARTING TUESDAY AFTERNOON OUT THROUGH THURSDAY. AT THIS
TIME...TEMPERATURES APPEAR TOO WARM FOR ANY SNOW AT LOWER
ELEVATIONS.
AVIATION...VFR CONDITIONS WILL PREVAIL THROUGH TONIGHT. NORMAL
LIGHT SOUTHERLY DRAINAGE WINDS AT KDEN AND KAPA WILL BECOME LIGHT
AFTER SUNRISE. BY 18Z...NORTH TO NORTHEAST WINDS WILL DEVELOP AT
SPEEDS LESS THAN 15 KNOTS. LIGHT WINDS ARE EXPECT TO REDEVELOP
TONIGHT.
HYDROLOGY...NO CONCERNS.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....BAKER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
107 PM EDT FRI MAY 03 2013
...Updated Aviation Discussion...
.Forecast Update...
Issued at 1155 AM EDT Fri May 3 2013
12Z Models continue to advertise a sharp cutoff in precipitation on
the northeast side of the large band of rain expected to setup as
the upper low now over the Central Plains starts travelling
southeast. Have begun to trim pops over the northeast forecast area,
including a tweak downward for the Louisville area for tomorrow.
Pops over the south still look pretty solid. Given the slow-moving
nature of the line across our forecast area combined with heavy
rains that fell earlier, as well as ensemble guidance indicating
rivers across the south likely will go to flood stage, have decided
to go ahead and issue a flood watch across south central Kentucky.
Issued at 905 AM EDT Fri May 3 2013
Atmosphere much less capped than yesterday, as seen from the earlier
showers we had over the northwest forecast area this morning. The
limiting factor will be dry air over the east. The ARW and NMM
versions of the WRF as well as the latest RAP all have a band of
showers and storms forming at the edge of this dry air, which would
be along the I-65 corridor, later this afternoon.
As for the more steady rains coming in, models are fine tuning where
the band will set up and move (slowly). There looks to be a sharp
cutoff over the northeast, and the heaviest rains look to fall where
we`ve had plenty of rain already in the last month. Given that
earlier rain we may have to go with a flood watch across south
central Kentucky and will decide after seeing the 12Z model data.
Issued at 520 AM EDT Fri May 3 2013
Did a quick update to increase PoPs a bit across our western
sections due to the batch of showers moving northward through
southwestern Indiana. Also have some isolated showers that have
popped up on the east side of I-65 as well, so have also expanded
PoPs a little further east.
&&
.Short Term (Now through Saturday)...
Issued at 324 AM EDT Fri May 3 2013
In the near term, partly to mostly cloudy skies are expected to
persist across the region. Early morning radar imagery shows a few
isolated showers moving northward across our western CWA...mainly
west of I-65. We expect the isolated showers to continue through
the remainder of the early morning hours west of I-65. Temperatures
remained quite mild with readings in the upper 50s in the southeast
sections with lower 60s elsewhere. Temperatures will probably drop
another 1-2 degrees before hitting their overnight minimums.
Stalled out boundary out to our west is forecast to make very slow
progress eastward today, mainly staying out near the Mississippi
river. Southeasterly winds will pick up today as the pressure
gradient increases across the region. Plenty of clouds are expected
across the western half of the region today with a little less in
the east. Moisture plume out ahead of the slow moving boundary will
help generate waves of showers mainly to our west. Previous
forecast has a very good handle here with isolated-scattered showers
and possibly a thunderstorm or two mainly west of I-65 during the
afternoon hours. Current data still supports this, so only some
minor tweaks to the grids were made here. Temperatures this
afternoon will warm into the mid-upper 70s with the highest temps
out across the east where the veil of clouds is expected to be a bit
thinner.
By tonight, the frontal boundary out to the west is forecast to
start making some eastward progress as the deep closed low out over
the Plains gets more organized and deepens. Rain showers will be
most concentrated out across our western sections and then
overspread much of central Kentucky by sunrise Saturday. Light
southeasterly flow and plenty of cloud cover will result in mild
overnight minimum temperatures with readings cooling into the
mid-upper 50s.
Saturday, by all accounts, will be cloudy and wet across the region
as the surface frontal boundary occludes across the region. Band of
showers over western Kentucky is expected to gradually spread
eastward across the central part of the state throughout the day.
The rain will generally be light to moderate, but could be a little
heavy at times especially across southern Kentucky. Instability is
virtually not existent so not expecting much in the way of thunder.
However, with the good moisture fetch off the SW Atlantic, training
of rain showers looks increasingly likely which could lay down
around an inch of rain in some spots by Saturday evening. The
clouds and precipitation will keep temperatures down on Saturday
with highs only warming into the upper 50s.
.Long Term (Saturday Night through Thursday)...
Issued at 300 AM EDT Fri May 3 2013
The well advertised cutoff upper level low will be over Arkansas at
the beginning of the long term. This low will slowly swing across
the southeastern CONUS and into northern GA by Monday morning. It
will then work its way up the Atlantic coast through mid week.
The fetch of moisture off the Atlantic will continue to wrap around
the northern side of the low as it slides south of the forecast area
through the end of the weekend. Moderate rain will continue across
much of the area Saturday night through Sunday. Through this time
period an rainfall totals look to range from half an inch across
portions of the Bluegrass and southern Indiana to an inch south of
the Bluegrass Parkway. Some minor flooding will be possible on area
rivers with this rain. For more information refer to the hydrology
discussion below.
Rain chances will continue off and on through the first half of the
work week. However, these will become more diurnal in nature as the
low moves up the coast. A few thunderstorms will be possible with
this activity, especially if the sun is able to break out at all.
Thursday finally looks to be dry under ridging aloft.
Temperatures will remain on the cool side Sunday with highs only in
the lower 60s. However we will see a warming trend through the week.
By Thursday high temperatures should be back into the upper 70s with
lows in the mid to upper 50s.
&&
.Aviation (18Z TAF Issuance)...
Issued at 105 PM EDT Fri May 3 2013
Stalled frontal boundary remains out to our west, but we should
start to see some movement this period, as a developing upper low
over the Central Plains drifts southeast into Arkansas tonight. We
may see an isolated storm this afternoon, as moisture starts to
increase ahead of this system. However coverage looks isolated
enough to leave out of each of the terminals for now. High-res
models continue to show some storms along a NW/SE-oriented band near
KSDF later this afternoon, but would prefer to wait and see
development before adding to the TAFs. More solid rain chances will
start, first at KBWG late tonight then at KSDF Saturday morning.
Have enough confidence in at least MVFR conditions as we get deeper
into the moisture, so put these in 6-7 hours after the showery
activity starts.
&&
.Hydrology...
Issued at 300 PM EDT Thu May 2 2013
An upper air disturbance is forecast to move across the region this
weekend. This will result in moderate to heavy rainfall over
southern Kentucky. Between Friday afternoon and Sunday morning
between one and inch inches could fall with the heaviest amounts
near Bowling Green.
This area recently had minor flooding and this new rain could result
in a new round of flooding in the middle of the Green River Basin.
Residents with livestock or equipment in flood prone areas should
watch water levels closely this weekend.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...FLOOD WATCH FROM SATURDAY MORNING THROUGH SUNDAY EVENING FOR
KYZ026-027-061>066-070>078-081-082.
$$
Updates..........RJS
Short Term.......MJ
Long Term........EER
Aviation.........RJS
Hydrology........CMC
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
700 PM EDT FRI MAY 3 2013
.SYNOPSIS...
ISSUED AT 329 PM EDT FRI MAY 3 2013
UNSEASONABLY WARM TEMPERATURES WILL PERSIST THROUGH THE WEEKEND INTO
EARLY NEXT WORK WEEK. EAST WINDS WILL KEEP TEMPERATURES WARM ALL
THE WAY TO THE LAKE SHORE. THE NEXT GOOD CHANCES FOR RAIN DO NOT
ARRIVE UNTIL WEDNESDAY NIGHT INTO THURSDAY.
&&
.UPDATE...
ISSUED AT 522 PM EDT FRI MAY 3 2013
I UPDATED THE GRIDS TO BETTER MATCH THE TEMP/DEW POINT GRADIENT
NEAR US-31 OVER THE NEXT FEW HOURS. I ALSO USING A COMBINATION OF
THE HRRR 19Z AND RAP MODEL UPDATED THE POP/WEATHER GRIDS TO SHOW
THE SHOWERS LIFTING OUT TO THE NORTHWEST OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 329 PM EDT FRI MAY 3 2013
CONVECTION HAS RECENTLY DEVELOPED ALONG THE INVERTED TROUGH/LAKE
BREEZE BOUNDARY IN A REGION OF BETTER INSTABILITY CENTERED MAINLY
SOUTH OF MUSKEGON. EXPECT A RAPID DECREASE IN ACTIVITY AGAIN THIS
EVENING WITH A LOSS OF INSOLATION.
AFTER THIS EVENING...DRY CONDITIONS WITH EAST WINDS WILL PERSIST
THROUGH THE WEEKEND. THIS IS A WARM AND DRY PATTERN SO WENT ABOVE
GUIDANCE TEMPERATURES...ESPECIALLY ALONG THE LAKESHORE WHICH CAN
WARM SIGNIFICANTLY WITH THIS TYPE OF PATTERN WHERE SLIGHT
DOWNSLOPING COMES INTO PLAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 PM EDT FRI MAY 3 2013
HAVE A DRY FORECAST FROM MONDAY THROUGH WEDNESDAY NIGHT AS THE LOW
OVER THE SOUTHEAST U.S. AIDES IN KEEPING A RIDGE OVER THE GREAT
LAKES. DRY AND WARM WEATHER IS FORECAST TO CONTINUE WITH HIGHS NEAR
70 OR INTO THE LOWER 70S EACH DAY NEXT WEEK. THE NEXT CHANCE FOR
PRECIPITATION COMES OUT ON THURSDAY WHEN AN UPPER SHORTWAVE TROUGH
IS PROGD TO SLIP THROUGH THE AREA. GIVEN UPPER LOWS SITUATED OVER
THE LOWER 48 AND THE SHORTWAVE IS ON THE SOUTHERN EDGE OF THE
WESTERLIES...CONFIDENCE IS LOWER IN ITS PLACEMENT AT DAY 6 IN THE
FORECAST.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING)
ISSUED AT 700 PM EDT FRI MAY 3 2013
VFR CIGS WILL PREVAIL THROUGH SATURDAY. AS THE SYSTEM MOVES SOUTH
OF MICHIGAN TONIGHT THROUGH SATURDAY THE IMPACT FOR SOUTHWEST
MICHIGAN IS DEEP SOUTHEAST WINDS AND CEILING WELL ABOVE 10000 FT
AGL.
THE SHOWERS NEAR THE LAKE SHORE LATE THIS AFTERNOON HAVE ALREADY
MOVED OUT OVER THE LAKE TO THE NORTHWEST OF MUSKEGON AND ARE NOT
EXPECTED TO COME BACK.
&&
.MARINE...
ISSUED AT 329 PM EDT FRI MAY 3 2013
NO CHANGES TO THE FORECAST PLANNED AT THIS TIME. AFTER WINDS AND
WAVES
SUBSIDE THIS EVENING...GENERALLY LIGHT OFFSHORE WINDS WILL PRECLUDE
THE NEED FOR HEADLINES.
&&
.FIRE WEATHER...
ISSUED AT 329 PM EDT FRI MAY 3 2013
WITH EASTERLY WINDS OVER THE WEEKEND...WE ARE IN A FAVORABLE SETUP
FOR
WARM AND DRY CONDITIONS. THE LATEST PLANNING FORECAST ISSUANCE BRINGS
SOME AREAS CLOSER TO RED FLAG WARNING CRITERIA. TEMPERATURE AND
HUMIDITY THRESHOLDS WILL BE SOMETHING TO CLOSELY WATCH OVER THE
NEXT COUPLE DAYS. HOWEVER...WIND SPEEDS SHOULD ALSO BE DECREASING
FROM SATURDAY TO SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 329 PM EDT FRI MAY 3 2013
NO CONCERNS DUE TO LITTLE OR NO EXPECTED PRECIPITATION OVER THE
NEXT SEVERAL DAYS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...DUKE
AVIATION...WDM
FIRE WEATHER...TJT
HYDROLOGY...TJT
MARINE...TJT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
524 PM EDT FRI MAY 3 2013
.SYNOPSIS...
ISSUED AT 329 PM EDT FRI MAY 3 2013
UNSEASONABLY WARM TEMPERATURES WILL PERSIST THROUGH THE WEEKEND INTO
EARLY NEXT WORK WEEK. EAST WINDS WILL KEEP TEMPERATURES WARM ALL
THE WAY TO THE LAKE SHORE. THE NEXT GOOD CHANCES FOR RAIN DO NOT
ARRIVE UNTIL WEDNESDAY NIGHT INTO THURSDAY.
&&
.UPDATE...
ISSUED AT 522 PM EDT FRI MAY 3 2013
I UPDATED THE GRIDS TO BETTER MATCH THE TEMP/DEW POINT GRADIENT
NEAR US-31 OVER THE NEXT FEW HOURS. I ALSO USING A COMBINATION OF
THE HRRR 19Z AND RAP MODEL UPDATED THE POP/WEATHER GRIDS TO SHOW
THE SHOWERS LIFTING OUT TO THE NORTHWEST OVER THE NEXT FEW HOURS.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 329 PM EDT FRI MAY 3 2013
CONVECTION HAS RECENTLY DEVELOPED ALONG THE INVERTED TROUGH/LAKE
BREEZE BOUNDARY IN A REGION OF BETTER INSTABILITY CENTERED MAINLY
SOUTH OF MUSKEGON. EXPECT A RAPID DECREASE IN ACTIVITY AGAIN THIS
EVENING WITH A LOSS OF INSOLATION.
AFTER THIS EVENING...DRY CONDITIONS WITH EAST WINDS WILL PERSIST
THROUGH THE WEEKEND. THIS IS A WARM AND DRY PATTERN SO WENT ABOVE
GUIDANCE TEMPERATURES...ESPECIALLY ALONG THE LAKESHORE WHICH CAN
WARM SIGNIFICANTLY WITH THIS TYPE OF PATTERN WHERE SLIGHT
DOWNSLOPING COMES INTO PLAY.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 342 PM EDT FRI MAY 3 2013
HAVE A DRY FORECAST FROM MONDAY THROUGH WEDNESDAY NIGHT AS THE LOW
OVER THE SOUTHEAST U.S. AIDES IN KEEPING A RIDGE OVER THE GREAT
LAKES. DRY AND WARM WEATHER IS FORECAST TO CONTINUE WITH HIGHS NEAR
70 OR INTO THE LOWER 70S EACH DAY NEXT WEEK. THE NEXT CHANCE FOR
PRECIPITATION COMES OUT ON THURSDAY WHEN AN UPPER SHORTWAVE TROUGH
IS PROGD TO SLIP THROUGH THE AREA. GIVEN UPPER LOWS SITUATED OVER
THE LOWER 48 AND THE SHORTWAVE IS ON THE SOUTHERN EDGE OF THE
WESTERLIES...CONFIDENCE IS LOWER IN ITS PLACEMENT AT DAY 6 IN THE
FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 245 PM EDT FRI MAY 3 2013
EXPECTING VFR CONDITIONS THE NEXT 24 HOURS...AS SOUTHWEST LOWER
MICHIGAN REMAINS ON THE PERIPHERY OF AN UPPER LOW TO OUR
SOUTHWEST. CEILINGS BETWEEN 5000-8000FT CAN BE EXPECTED THIS
AFTERNOON AND EVENING AS CUMULUS CLOUDS BUBBLE UP IN THE HEAT OF
THE DAY. HAVE INCLUDED VCSH AT KMKG...KGRR AND KAZO FROM 21Z
THROUGH 04Z. THE HIGH BASED CUMULUS SHOULD DISSIPATE TOWARDS
MIDNIGHT...WITH CLOUDS AT OR ABOVE 10000FT TONIGHT INTO SATURDAY
MORNING. WIND DIRECTION WILL BE SOUTHEAST FOR THE MOST PART
OUTSIDE OF A LAKE BREEZE THAT PUSHES SLIGHTLY INLAND THIS
AFTERNOON.
&&
.MARINE...
ISSUED AT 329 PM EDT FRI MAY 3 2013
NO CHANGES TO THE FORECAST PLANNED AT THIS TIME. AFTER WINDS AND
WAVES
SUBSIDE THIS EVENING...GENERALLY LIGHT OFFSHORE WINDS WILL PRECLUDE
THE NEED FOR HEADLINES.
&&
.FIRE WEATHER...
ISSUED AT 329 PM EDT FRI MAY 3 2013
WITH EASTERLY WINDS OVER THE WEEKEND...WE ARE IN A FAVORABLE SETUP
FOR
WARM AND DRY CONDITIONS. THE LATEST PLANNING FORECAST ISSUANCE BRINGS
SOME AREAS CLOSER TO RED FLAG WARNING CRITERIA. TEMPERATURE AND
HUMIDITY THRESHOLDS WILL BE SOMETHING TO CLOSELY WATCH OVER THE
NEXT COUPLE DAYS. HOWEVER...WIND SPEEDS SHOULD ALSO BE DECREASING
FROM SATURDAY TO SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 329 PM EDT FRI MAY 3 2013
NO CONCERNS DUE TO LITTLE OR NO EXPECTED PRECIPITATION OVER THE
NEXT SEVERAL DAYS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...WDM
SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...DUKE
AVIATION...DUKE
FIRE WEATHER...TJT
HYDROLOGY...TJT
MARINE...TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
418 PM EDT FRI MAY 3 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 418 PM EDT FRI MAY 3 2013
UPPER TROUGH CONTINUES TO SPLIT APART NEXT 24 HRS WITH UPPER LOW
FOCUSING OVER CNTRL MISSISSIPPI RIVER VALLEY. REGIONAL RADAR SHOWS
SWATH OF MAINLY RAIN FROM ILLINOIS INTO WISCONISN AND INTO WESTERN
UPR MICHIGAN AND INTO MINNESOTA ARROWHEAD. THIS PRECIP IS SUPPORTED
BY PERSISTENT H85-H7 FRONTOGENESIS AND RIGHT ENTRANCE REGION FROM
UPPER JET OVER ONTARIO. BOTH FEATURES ARE FORECAST TO DIMINISH INTO
SATURDAY AS UPPER LOW TO THE SOUTH BECOMES DOMINANT UPPER LEVEL
FEATURE.
ANALYSIS FROM RUC AND NAM INDICATING WARM LAYER IS WELL ABOVE 0C
SUGGESTS PTYPE OVER WESTERN UPR MICHIGAN SHOULD BE RAIN BUT REPORTS
FROM GOGEBIC INTO SOUTHERN HOUGHTON COUNTY SHOW IT IS NOT WITH LGT
SNOW OCCURRING. THESE AREAS LINE UP WELL WITH SUB ZERO 950-900MB
TEMPS SO KEPT MENTION OF SLEET/SNOW OVER FAR WESTERN UPR MICHIGAN
THROUGH EARLY MORNING HOURS BEFORE SHALLOWER COLD TEMPS WARM ABOVE
0C. OTHERWISE...RAIN WILL BE DOMINANT PTYPE ACROSS REST OF
CWA...MORE SCATTERED IN THE EASTERN HALF OF CWA. KEPT A MENTION OF
FZRA OVER INLAND WESTERN THIRD OF CWA. SINCE MAJORITY OF PRECIP WILL
OCCUR OVER WESTERN CWA AND SINCE THERE IS GOING TO BE CONTINUING
FZRA/SLEET/SNOW...CHANGING TO RAIN/FREEZING RAIN...OPTED TO KEEP
WINTER WEATHER ADVY OUT FOR GOGEBIC AND ONTONAGON COUNTIES THROUGH
12Z SATURDAY. COULD SEE SIMILAR PYTPE THIS EVENING FARTHER EAST
ACROSS KEWEENAW...BUT BASED ON UPSTREAM RADAR TRENDS AND BLEND OF
SHORT TERM MODELS...THINK THESE AREAS WILL MISS OUT ON HEAVIER QPF
AND BETTER CHANCE OF SLEET/ICE ACCUMS.
IMPROVING WEATHER ON SATURDAY...HOPEFULLY. LINGERING DIVERGENCE
ALOFT MAY STILL BRING SOME LGT RAIN OVER WEST AND NORTHWEST CWA.
SHOULD STAY DRY OVER THE EAST HALF. SIMILAR TO LAST COUPLE DAYS
SHOULD BE A WIDE TEMPERATURE RANGE FROM WEST TO EAST. BASED ON FCST
H85 TEMPS AND CLEARER SKIES EXPECTED...THINKING EASTERN INTERIOR
CWA MAY REACH MID 60S TO LOWER 70S. COOLER NORTH FLOW KEEPS WEST AND
CNTRL COOLER...BUT STILL A BIT WARMER THAN RECENT TEMPERATURES.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 418 PM EDT FRI MAY 3 2013
NAM SHOWS A CLOSED 500 MB LOW OVER NORTHERN CA AND ANOTHER OVER
NORTHERN ARKANSAS WITH A 500 MB RIDGE OVER THE LOWER GREAT LAKES.
THE 500 MB PATTERN OVER THE EAST HALF OF THE U.S. IS AN OMEGA BLOCK
00Z SUN AND DOES NOT MOVE MUCH ON SUNDAY EXCEPT TO TRY TO FORM A REX
BLOCK WITH THE LOW MOVING SLOWLY EAST UNDERNEATH THE RIDGE. THE REX
BLOCK THEN GETS ESTABLISHED ON MON. THIS FORECAST PERIOD FEATURES
DEEPER MOISTURE OVER THE WEST HALF OF THE CWA GRADUALLY DECREASING.
WILL KEEP SLIGHT CHANCE POPS OVER THE FAR WESTERN CWA SAT NIGHT WITH
THIS MOVING FURTHER WEST WITH TIME ON SUN. PCPN SHOULD BE ALL RAIN
BY THAT TIME. TEMPERATURES CONTINUE THE SLOW WARMING TREND WITH TIME
AND DRY WEATHER COMES IN FOR SUN INTO MON. DID NOT MAKE TOO MANY
CHANGES TO THE GOING FORECAST FOR TEMPERATURES EXCEPT DID LOWER LOWS
A BIT WITH THE COLDER MOS GUIDANCE FOR SAT NIGHT AND SUN NIGHT.
IN THE EXTENDED...ECMWF AND GFS SHOW A CLOSED 500 MB LOW OVER THE
SOUTHEAST U.S. 12Z TUE. THINGS GET INTERESTING OVER THE NORTHERN
PLAINS. 12Z TUE...ECMWF HAS A CLOSED 500 MB LOW NEAR SISSETON SD AND
THE GFS HAS A 500 MB RIDGE THERE INSTEAD. THIS DIFFERENCE CARRIES
INTO 12Z WED WITH THE ECMWF CONTINUING ITS SOLUTION OF A TROUGH IN
THE UPPER MISSISSIPPI VALLEY WITH THE 06Z GFS HAVING A CLOSED 500 MB
LOW OVER MISSOURI WHILE THE 00Z GFS STILL MAINTAINING A RIDGE OVER
THE CORNBELT. THE ECMWF TAKES THE TROUGH INTO THE UPPER GREAT LAKES
12Z THU WITH THE GFS MAINTAINING A FLAT 500 MB RIDGE OVER THE AREA.
THE 500 MB RIDGE GETS FLATTENED BY 12Z FRI WITH A BROAD 500 MB
TROUGH AND THE WESTERLIES GETTING PUSHED SOUTH INTO THE AREA.
CONFIDENCE REMAINS LOW WITH THIS EXTENDED FORECAST DUE TO THE 2 VERY
DIFFERENT MODEL SOLUTIONS. LOOKS DRY THROUGH TUE NIGHT BEFORE A COLD
FRONT HEADS SOUTH OUT OF CANADA AND BRINGS WITH IT A SLIGHT CHANCE
TO LOW CHANCE FOR PCPN WED INTO FRI. TEMPERATURES CONTINUE TO SLOWLY
WARM AND GO TO NEAR NORMAL BY THE END OF THE PERIOD. THE COLD FRONT
MOVES THROUGH WED NIGHT AND SLOWLY PUSHES SOUTH OF THE AREA THEN FOR
THU INTO FRI.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 149 PM EDT FRI MAY 3 2013
CIGS REMAIN FAIRLY SIMILAR THROUGH THE TAF PERIOD AS LOW LEVEL
MOISTURE IS ABUNDANT. BASED ON UPSTREAM RADAR AND OBSERVATION
TRENDS...STILL DECENT CHANCE OF SEEING ADDITIONAL PRECIP AT IWD BY
THIS EVENING...PROBABLY IN THE FORM OF FZRA/FZDZ. BETTER CHANCE FOR
PRECIP AT SAW...SCT SHOWERS...WILL BE AROUND SUNSET. THERE WILL BE
BETTER CHANCE OF DZ/FZDZ BY THIS EVENING AND THROUGH THE NIGHT AT CMX.
HAVE WENT WITH A RETURN TO IFR VSBY AT SAW LATER THIS EVENING THROUGH
DAYBREAK SATURDAY GIVEN PERSISTENT UPSLOPE FLOW AND SUBSIDENCE
INVERSION SETTING UP LATER TONIGHT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 418 PM EDT FRI MAY 3 2013
NO GALES SEEN DURING THIS FORECAST PERIOD. THE STRONGEST WINDS IN
THE PERIOD ARE THIS AFTERNOON WITH NORTHEAST WINDS BELOW 25 KNOTS. A
HIGH PRESSURE RIDGE SETTLES IN AND KEEPS STRONG SYSTEMS AWAY FROM
THE AREA.
&&
.HYDROLOGY...
ISSUED AT 418 PM EDT FRI MAY 3 2013
STURGEON RIVER AT ALSTON AND CHASSELL...THE MICHIGAMME RIVER AROUND
WITCH LAKE...AND THE PAINT RIVER NEAR CRYSTAL FALLS WILL REMAIN
CONCERNS INTO AT LEAST EARLY NEXT WEEK...BUT OTHERWISE RIVER LEVELS
CONTINUE TO COME DOWN. ACTUALLY...MICHIGAMME MAY REMAIN A CONCERN
THROUGH MOST OF NEXT WEEK. DECENT AMOUNT OF WATER EQUIVALENT HAS
OCCURRED LAST TWO DAYS OVER WESTERN CWA...VCNTY OF IRONWOOD TO
ONTONAGON...OVER 2 INCHES OVER FAR WESTERN GOGEBIC COUNTY. WILL HAVE
TO ASSESS WHAT AFFECT THE PRECIP WILL HAVE WHEN COMBINED WITH
FURTHER MELTING OF ANY SUSTAINED SNOWPACK WHEN TEMPS WARM INTO THE
60-70S SUN INTO NEXT WEEK. SNOW WATER EQUIVALENT OF 8.8 INCHES IN
PAINESDALE ON THURSDAY WITH 24 INCHES OF SNOW DEPTH...SO THE OTTER
RIVER STILL HAS PLENTY OF SNOW IN THE HEADWATERS WHICH MAY CAUSE
ADDITIONAL PROBELMS AT CLLM4 IN THE COMING DAYS.
FOR COMPLETE DETAILS...SEE THE LATEST RIVER FLOOD WARNINGS AND
ADVISORIES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 8 AM EDT /7 AM CDT/ SATURDAY FOR
MIZ002-009.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLA
LONG TERM...07
AVIATION...JLA
MARINE...07
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
246 PM EDT FRI MAY 3 2013
.SYNOPSIS...
ISSUED AT 340 AM EDT FRI MAY 3 2013
IT WILL BE MILD TODAY WITH SCATTERED AFTERNOON SHOWERS AND A FEW
THUNDERSTORMS MAINLY WEST OF A LINE FROM KALAMAZOO TO GRAND RAPIDS
AND BIG RAPIDS. DRY AND MILD WEATHER IS ANTICIPATED THROUGH THE
WEEKEND AND FOR MOST OF NEXT WEEK.
&&
.UPDATE...
ISSUED AT 932 AM EDT FRI MAY 3 2013
UPDATED FORECAST TO ACCOUNT FOR RAIN SHOWERS CURRENTLY OVER FAR
SW CWA. HAVE GENERALLY RAISED POPS NEAR THE LAKESHORE INTO THE
AFTERNOON. LATEST HRRR GUIDANCE SUGGESTS THAT AREA OF PRECIPITATION
OVER CENTRAL IN WILL MOVE NORTH...REACHING OUR SOUTHERN CWA BY
THIS EVENING. WILL MONITOR THIS AND MAY BE RAISING POPS SOUTH OF
I-96 LATER TODAY IF THESE TRENDS CONTINUE.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY AFTERNOON)
ISSUED AT 340 AM EDT FRI MAY 3 2013
OUR PRIMARY SHORT TERM FCST CHALLENGE IS TO DETERMINE PROBABILITIES
FOR SCATTERED SHOWERS/TSTORMS TODAY. AS WAS THE CASE YESTERDAY
AFTERNOON WE EXPECT SFC CONVERGENCE FROM AN INVERTED SFC TROF AND
THE LAKE BREEZE TO TRIGGER DEVELOPMENT OF SHOWERS AND A FEW STORMS
THIS AFTERNOON... WITH THE RELATIVELY BEST CHC FOR THOSE WEST OF
US-131 AS SUGGESTED BY LATEST 00Z 4KM WRF-NMM SIM Z GUIDANCE. MAX
TEMPS WILL REACH THE LOW TO MID 70S EXCEPT SIGNIFICANTLY COOLER
RIGHT ALONG THE LAKE MI SHORELINE.
DRY AND SEASONABLY MILD WX IS THEN EXPECTED TONIGHT THROUGH SUNDAY
AS THE UPPER RIDGE AXIS TAKES HOLD AND UPPER LOW DRIFTS FURTHER SE
INTO THE SOUTHEASTERN UNITED STATES. MAX TEMPS THIS WEEKEND SHOULD
AGAIN REACH THE LOW TO MID 70S. THE EASTERLY WINDS WILL LIKELY NOT
BE STRONG ENOUGH TO PRECLUDE LAKE BREEZE DEVELOPMENT SATURDAY AND
SUNDAY... SO LOCATIONS RIGHT ALONG LAKE MI SHOULD AGAIN BE COOLER.
.LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY)
ISSUED AT 340 AM EDT FRI MAY 3 2013
LOOKS LIKE A QUIET WEATHER PATTERN IN THE EXTENDED AS THE UPPER LOW
TRACKS WELL SOUTH OF THE GREAT LAKES AND DRY EAST FLOW DOMINATES.
ADDED SLIGHT CHANCE POPS FOR THURSDAY AS WEAKER...NORTHERN CUT OFF
LOW FINALLY MOVES EAST AND OVER LOWER MICHIGAN. THIS SHOULD BE
MOISTURE STARVED SINCE IT HAS LITTLE OR NO GULF MOISTURE TO WORK
WITH.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 245 PM EDT FRI MAY 3 2013
EXPECTING VFR CONDITIONS THE NEXT 24 HOURS...AS SOUTHWEST LOWER
MICHIGAN REMAINS ON THE PERIPHERY OF AN UPPER LOW TO OUR
SOUTHWEST. CEILINGS BETWEEN 5000-8000FT CAN BE EXPECTED THIS
AFTERNOON AND EVENING AS CUMULUS CLOUDS BUBBLE UP IN THE HEAT OF
THE DAY. HAVE INCLUDED VCSH AT KMKG...KGRR AND KAZO FROM 21Z
THROUGH 04Z. THE HIGH BASED CUMULUS SHOULD DISSIPATE TOWARDS
MIDNIGHT...WITH CLOUDS AT OR ABOVE 10000FT TONIGHT INTO SATURDAY
MORNING. WIND DIRECTION WILL BE SOUTHEAST FOR THE MOST PART
OUTSIDE OF A LAKE BREEZE THAT PUSHES SLIGHTLY INLAND THIS
AFTERNOON.
&&
.MARINE...
ISSUED AT 340 AM EDT FRI MAY 3 2013
WE WILL ALLOW THE SCA TO EXPIRE EARLY THIS MORNING. WAVE HEIGHTS OF
2 TO 4 FEET ARE ANTICIPATED TODAY BUT WAVES AND WINDS WILL STAY BELOW
SCA CRITERIA. MINIMAL WAVE ACTION IS ANTICIPATED THIS WEEKEND WITH
OFFSHORE WINDS.
&&
.FIRE WEATHER...
ISSUED AT 340 AM EDT FRI MAY 3 2013
A FEW SHOWERS AND THUNDERSTORMS ARE EXPECTED TODAY. AFTER TODAY DRY
AND MILD WEATHER IS EXPECTED THIS WEEKEND THROUGH MOST OF NEXT WEEK
KEEPING FUEL MOISTURE RATHER LOW.
&&
.HYDROLOGY...
ISSUED AT 340 AM EDT FRI MAY 3 2013
ANY PRECIPITATION TODAY FROM SCATTERED SHOWERS AND A FEW STORMS WILL
BE QUITE LIGHT. DRY WEATHER IS EXPECTED THIS WEEKEND THROUGH MOST OF
NEXT WEEK. THEREFORE THERE ARE NO SIGNIFICANT HYDRO CONCERNS AT THIS
TIME THAT WOULD AFFECT MAINSTEM RIVERS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...TJT
SYNOPSIS...LAURENS
SHORT TERM...LAURENS
LONG TERM...OSTUNO
AVIATION...DUKE
FIRE WEATHER...LAURENS
HYDROLOGY...LAURENS
MARINE...LAURENS
AREA FORECAST DISCUSSION
NWS DULUTH MN
1243 PM CDT FRI MAY 3 2013
.AVIATION...18Z TAF ISSUANCE
PRECIPITATION IN VARIOUS FORMS WILL CONTINUE ACROSS THE
REGION THIS AFTERNOON...WEST OF A LINE FROM KINL THROUGH
KDLH...THEN SPREAD EAST INTO KBRD AFT 00Z. MOST OF THE
PRECIPITATION WILL BE SNOW AT FIRST...THEN CHANGE TO RAIN OR
FREEZING RAIN...DEPENDING ON SFC TEMPS...WHICH WILL HOVER AROUND
FREEZING. CIGS WILL BE MAINLY MVFR THROUGH 00Z THEN DROP TO IFR IN
THE MAIN RAIN AREAS.
&&
.PREV DISCUSSION... /ISSUED 1025 AM CDT FRI MAY 3 2013/
UPDATE...
HAVE EXTENDED THE WINTER WEATHER ADVISORY FOR FREEZING RAIN OVER
NORTHERN WISCONSIN /EXCEPT PRICE COUNTY/ THROUGH 1000 PM THIS
EVENING...POSSIBLY NEEDING TO BE EXTENDED FURTHER. THE 12Z
NAM/DLHWRF BOTH SHOW SFC TEMPS REMAIN BELOW FREEZING OVER THE
ADVISORY AREA THROUGH AT LEAST MIDNIGHT. MEANWHILE...AN S-SE H85
FLOW WILL CONTINUE TO WARM MID LEVELS THROUGH THE
DAY...DIMINISHING ANY LINGERING SNOW AND PROMOTING FREEZING RAIN
THIS AFTERNOON/TONIGHT.
HAVE INTRODUCED MENTION OF FREEZING RAIN TO MN ARROWHEAD ZONES
THIS AFTERNOON AND EVENING WHERE H80-H85 LAYER TEMPS WARM A FEW
DEGREES ABOVE 0 C...WHILE SFC READINGS REMAIN SUB-FREEZING. WE
WILL CLOSELY MONITOR THIS AREA FOR ICE ACCUM POTENTIAL...AND AN
ADVISORY MAY BE NEEDED THIS AFTERNOON/TONIGHT FOR LAKE COOK
COUNTIES.
PREV DISCUSSION... /ISSUED 408 AM CDT FRI MAY 3 2013/
.SHORT TERM...TODAY THROUGH SATURDAY.
AT 4 AM...IT WAS FAIRLY QUIET ACROSS THE NORTHLAND. THERE WAS SOME
LIGHT SNOW ACROSS NW WI...AND REPORTS JUST OUTSIDE OF THE CWA OF
SOME LIGHT FREEZING DRIZZLE. TEMPERATURES RANGED FROM THE 20S IN
NE MN TO AROUND 30 IN NW WI.
THE NEXT MAIN WAVE OF PRECIPITATION WAS QUICKLY STREAMING
NORTHWARD THROUGH THE PLAINS. WE SHOULD SEE AN INCREASE
THROUGHOUT THE MORNING ACROSS WESTERN WISCONSIN. DEFINITELY SOME
PTYPE ISSUES...AND A THOROUGH ASSESSMENT OF THE FORECAST SOUNDINGS
SHOW SOME PRETTY SIGNIFICANT DIFFERENCES AMONG THE MODELS. JUST A
FEW DEGREES DIFFERENCE IN THE WARM LAYER WILL MEAN A CHANGE FROM
FREEZING RAIN OR RAIN...TO SLEET AND/OR SNOW.
FOR TODAY...HAVE RAISED POPS A BIT THROUGHOUT THE DAY...FIRST WITH
LIKELY POPS IN THE EASTERN 1/3 OF THE CWA...AND THEN SPREADING IT
NORTHWARD AND WESTWARD AS THE MORNING WEARS ON. NAM BUFR SOUNDINGS
AND THE HRRR FORECAST PTYPE INDICATE THAT A MIXTURE COULD LAST
INTO THE AFTERNOON...AND THERE MAY BE SOME SLEET AS WELL.
FORECAST LAYER THICKNESS VALUES ALSO INDICATE SOME POTENTIAL FOR
THIS TO LAST INTO THE AFTERNOON AND EVEN TONIGHT. WILL EXTEND THE
ADVISORY TIME THROUGH NOON WITH THE CAVEAT THAT SOME AREAS MAY
NEED TO BE EXTENDED INTO THE AFTERNOON.
HAVE INCREASED POPS CONSIDERABLY TONIGHT AND ON SATURDAY...WITH
GENERALLY RAIN DURING THE EVENING AND RAIN AND/OR FREEZING RAIN
AFTER MIDNIGHT. IN GENERAL...WE SHOULD SEE MAINLY RAIN ON
SATURDAY. TEMPS WILL BE TRICKY DUE TO THE CLOUDS AND EXPECTED
PRECIPITATION.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY.
A TROUGH OF LOW PRESSURE AND BAROCLINIC ZONE IS EVIDENT SATURDAY
NIGHT...WEAKENING SUNDAY. THIS WILL LEAD TO A CHANCE FOR RAIN OVER
MUCH OF THE CWA SATURDAY NIGHT...DIMINISHING FROM NORTH TO SOUTH
SUNDAY. RIDGING WILL TAKE OVER MONDAY INTO MONDAY NIGHT AND LEAD TO
A DRY PERIOD.
CONFIDENCE DIMINISHES MONDAY NIGHT INTO AT LEAST MID WEEK...AS THE
ECMWF BRINGS IN A SHORTWAVE AND SUPPORTS THE CHANCE FOR SHOWERS
TUESDAY/WEDNESDAY. WE FOLLOWED CLOSER TO THIS SOLUTION DURING THAT
PERIOD.
THE MODELS THEN HAVE A FASTER WNW FLOW OVER FAR NORTHERN MN/SOUTHERN
CANADA BY LATE IN THE WEEK WITH A CONTINUED CHANCE FOR RAIN WITH
WEAK LOW PRESSURE AT THE SURFACE. WE HAVE POPS CONTINUING THROUGH
THE REST OF THE PERIOD...ALTHOUGH WERE NOT OVERLY IMPRESSED WITH THE
FORCING AND EXPECTED PRECIPITATION AMOUNTS.
TEMPERATURES WILL BE A BIT BELOW NORMAL SUNDAY...RISING INTO THE
SIXTIES MONDAY THROUGH THE END OF THE WEEK.
HYDROLOGY...
FLOOD WARNINGS CONTINUED FOR THE MISSISSIPPI RIVER AT AITKIN AND
FORT RIPLEY FOR MINOR FLOODING. WE DROPPED THE WARNING FOR THE
SAINT LOUIS RIVER IN SCANLON AS THERE IS A CLEAR LOWERING TREND.
A FLOOD WARNING REMAINS FOR CENTRAL AND SOUTHERN SAINT LOUIS
COUNTY AS THERE IS STILL FLOODING OCCURRING THERE WITH WATER OVER
SEVERAL ROADS ACCORDING TO THE SAINT LOUIS COUNTY HIGHWAY
DEPARTMENT. THE NUMBER OF CLOSED ROADS HAD DIMINISHED SINCE
YESTERDAY THOUGH. THERE IS STILL SNOW OVER NORTHERN
MINNESOTA...ESPECIALLY IN THE WOODS. COOLER TEMPS TODAY WILL SLOW
THE MELT...BUT TEMPS WILL START TO WARM THIS WEEKEND INTO NEXT
WEEK...KEEPING ELEVATED RIVERS/STREAMS.
WE CONTINUED THE WARNING ACROSS ASHLAND/IRON COUNTIES. THE
MONTREAL REMAINS HIGH...AND THE ASHLAND COUNTY COMMISSIONER
REPORTED SEVERAL ROADS UNDER WATER AS WELL. ALL THIS SNOW THAT HAS
RECENTLY FALLEN WILL START TO MELT THIS WEEKEND ALTHOUGH
TEMPERATURES WILL BE BELOW NORMAL UNTIL MONDAY/TUESDAY. THIS
SNOWFALL AS WELL AS SNOW THAT WAS ALREADY ON THE GROUND WILL KEEP
RIVERS AND STREAMS ELEVATED. THE BAD RIVER HAS FALLEN A COUPLE
FEET SINCE YESTERDAY...BUT COULD START TO RISE AGAIN AS THE SNOW
MELTS.
&&
.POINT TEMPS/POPS...
DLH 37 32 40 36 / 80 80 60 50
INL 47 29 51 33 / 10 10 10 10
BRD 49 34 45 38 / 10 50 60 40
HYR 33 32 44 34 / 90 90 60 30
ASX 34 32 39 33 / 90 90 60 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...WINTER WEATHER ADVISORY UNTIL 10 PM CDT THIS EVENING FOR
WIZ002>004-007-008.
LS...SMALL CRAFT ADVISORY UNTIL 1 AM CDT SATURDAY FOR LSZ121-143>148.
&&
$$
SHORT TERM...GRANING
LONG TERM....CLC
AVIATION...CLC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
135 PM EDT FRI MAY 3 2013
.SYNOPSIS...
HIGH PRESSURE CENTERED OVER NEW ENGLAND AND THE CANADIAN MARITIMES
WILL CONTINUE TO PROVIDE OUR REGION WITH BEAUTIFUL WEATHER THROUGH
THE WEEKEND INTO EARLY NEXT WEEK. TEMPERATURES DURING THAT STRETCH
WILL REMAIN ABOVE NORMAL WITH AFTERNOON HIGHS GENERALLY IN THE 70S.
LOOKING FURTHER DOWN THE ROAD...THERE IS LITTLE IF ANY CHANCE FOR
WIDESPREAD PRECIPITATION THROUGH NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
GORGEOUS SPRING WEATHER WILL BE FOUND ACROSS ALL OF WESTERN AND
NORTH CENTRAL NEW YORK THIS AFTERNOON AS HIGH PRESSURE OVER NEW
ENGLAND WILL KEEP A WEALTH OF SUNSHINE IN PLACE. IT WILL QUITE MILD
AS H85 TEMPS IN THE VCNTY OF 10C WILL SUPPORT MID AFTERNOON HIGHS IN
THE UPPER 70S ACROSS THE LAKE PLAINS...AS WELL AS IN THE GENESEE AND
SOUTHERN TIER VALLEYS. ONCE AGAIN...THE COOL SPOTS WILL BE NEAR LAKE
ONTARIO WHERE A LAKE BREEZE SHOULD KEEP READINGS IN THE 60S.
SPEAKING OF WHICH...THE KBUF RADAR IS ONCE AGAIN DOING A FINE JOB OF
ILLUMINATING THE LAKE BREEZE BOUNDARY OFF LAKE ONTARIO. AS OF 1730Z
THE FRONT WAS SLOWLY SETTLING SOUTH ACROSS THE SOUTHERN PORTIONS OF
NIAGARA AND ORLEANS COUNTIES AND EXTENDED TO JUST NORTH OF
ROCHESTER. THE HRRR SIMULATION IS HANDLING THIS THE BEST OF THE
FINER SCALE GUIDANCE PACKAGES. OTHERWISE...
THE HIGH AMPLITUDE OMEGA BLOCK RESPONSIBLE FOR THIS STRETCH OF FINE
WEATHER WILL GENERALLY REMAIN IN PLACE THROUGH SATURDAY...ALTHOUGH
DEEP CLOSED LOWS OVER THE SOUTHERN PLAINS AND EASTERN ATLANTIC WILL
PINCH OFF THE SRN PORTION OF THE BLOCKING RIDGE. WHILE THE CORE OF
THE HIGH WILL REMAIN IN PLACE OVER OUR REGION...THE AFOREMENTIONED
ERODING OF ITS SOUTHERN FLANK WILL ALLOW LOWER H85 TEMPS TO ADVECT
WESTWARD FROM THE COAST. AS A RESULT...H85 TEMPS WILL SETTLE TO
BETWEEN 6 AND 8C WHICH IN TURN WILL KEEP SATURDAYS HIGH TEMPS A BIT
LOWER (ABT 5 DEG F) THAN THOSE FROM THE PAST COUPLE DAYS.
IN TERMS OF LOW TEMPS TONIGHT...IT WILL ALSO BE A BIT COOLER WITH
MINS DROPPING BACK CLOSER TO TYPICAL ERLY MAY VALUES. TEMPS BY
DAYBREAK WILL RANGE FROM THE MID AND UPPER 30S IN THE SRN TIER
VALLEYS TO THE LOWER 50SALONG THE IAG ESCARPMENT FROM IAG TO ROC.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE NORTHEASTERN STATES
THROUGH THE WEEKEND. THIS WILL KEEP AN EXTENDED PERIOD OF FAIR AND
WARM WEATHER ACROSS WESTERN NEW YORK.
SKIES SHOULD BE MOSTLY CLEAR FOR THE WEEKEND...OUTSIDE OF PERHAPS
SOME SCATTERED CUMULUS INLAND OF THE LAKE BREEZE.
850MB TEMPS AVERAGING AROUND +6C WILL YIELD AFTERNOON HIGH TEMPS A
LITTLE LESS WARM THAN THE RECENT PAST FEW DAYS. HIGHS WILL BE IN THE
LOWER TO MID 70S FOR MOST LOCATIONS...BUT A WELL DEVELOPED LAKE
BREEZE CIRCULATION WILL BRING COOLER LAKE AIR A LITTLE FARTHER
INLAND. THIS WILL BE ESPECIALLY TRUE ON SUNDAY WHEN A NORTHERLY WIND
DEVELOPS FOLLOWING WHAT APPEARS TO BE A WEAK AND VERY DRY BACKDOOR
FRONT.
LOW TEMPERATURES WILL ALSO BE MILD THROUGH THE PERIOD...WITH LOWS
AROUND 50 ON THE LAKE PLAINS OF WESTERN NY...WITH 40S ACROSS THE
INTERIOR AND EAST OF LAKE ONTARIO.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE FORECAST FOR NEXT WEEK CONTINUES TO DEPEND ON THE PROGRESSION OF
A CUT-OFF LOW. WHILE SOME DETAILS STILL REMAIN UNCERTAIN...MODEL
CONSENSUS HAS COME INTO BETTER AGREEMENT OVER THE PAST COUPLE RUNS.
EXPECT THE CLOSED LOW TO START THE WEEK ACROSS THE SOUTHEASTERN
STATES. CONSENSUS THEN LIFTS THE LOW NORTHWARD TO THE MID-ATLANTIC
STATES TOWARD MID-WEEK...AND THEN THE LOW WILL LIKELY SLIDE TO THE
EAST AND OFF THE ATLANTIC COAST THURSDAY. WHILE THERE IS STILL SOME
CHANCE THE LOW WILL REACH US...THE VAST MAJORITY OF GUIDANCE KEEPS
THE UPPER LOW TOO FAR SOUTH TO BRING ANY PRECIPITATION TO OUR REGION.
IF THIS CONSENSUS HOLDS...EXPECT ANOTHER WEEK OF NICE WEATHER WITH
ABOVE NORMAL TEMPERATURES. THERE MAY BE A BIT MORE CLOUD COVER AS A
RESULT OF THE UPPER LOW. HOWEVER...850 MB TEMPERATURES SHOULD
CONTINUE TO RUN AROUND +10C. THIS WOULD ALLOW DAYTIME HIGHS TO
CONTINUE TO CLIMB INTO THE 70S THROUGH THE END OF THE WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
HIGH PRESSURE WILL KEEP LIGHT WINDS AND VFR CONDITIONS IN PLACE
THROUGH AT LEAST SATURDAY.
THE ONLY REAL FORECAST CHALLENGE WILL BE TIMING OF THE LAKE BREEZE
BOUNDARY OFF LAKE ONTARIO...WHICH WILL DROP SOUTH OF IAG/BUF AND
ROCHESTER AFTER 19Z THIS AFTERNOON...AND AGAIN SATURDAY AFETRNOON.
OUTLOOK...
SUNDAY THROUGH WEDNESDAY...VFR.
&&
.MARINE...
HIGH PRESSURE DOMINATING THE NORTHEASTERN UNITED STATES WILL PERSIST
THROUGH THE WEEKEND WITH LIGHT SOUTHEASTERLY FLOW RESULTING IN
TRANQUIL CONDITIONS ON THE LAKES. LAKE BREEZES WILL SET UP IN THE
EACH AFTERNOON.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...RSH
NEAR TERM...RSH
SHORT TERM...WCH
LONG TERM...APFFEL
AVIATION...RSH
MARINE...TMA
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
255 PM CDT FRI MAY 3 2013
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 255 PM CDT FRI MAY 3 2013
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES AND POSSIBLE
THUNDERSTORMS THROUGH PERIOD.
LATEST WATER VAPOR SATELLITE IMAGERY SHOWS UPPER LEVEL LOW CUTTING
OFF OVER THE CENTRAL PLAINS AND INDICATING GOOD FETCH OF MOISTURE
LIFTING NORTHWARD INTO THE UPPER MIDWEST AND GREAT LAKES REGION.
LATEST MOSAIC RADAR SHOWS RAIN ACROSS PORTIONS OF SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN INTO EASTERN IOWA AND NORTHERN
ILLINOIS. THIS IS IN RESPONSE TO DECENT MOISTURE TRANSPORT AND
CONVERGENCE IN THE 925-850MB LAYER PER 03.15Z RAP.
THE 03.12Z GFS/NAM ARE IN GOOD AGREEMENT IN MOVING UPPER LEVEL CUTOFF
LOW OVER THE SOUTHERN PLAINS AND SOUTHEAST UNITED STATES THROUGH
SATURDAY NIGHT. THE DETERMINISTIC MODELS CONTINUE TO SHOW A SERIES OF
SHORTWAVE TROUGHS WRAPPING AROUND UPPER LEVEL LOW INTO THE UPPER
MIDWEST. THE 03.12Z GFS/NAM AND 03.15Z RAP INDICATE THE AREA IS ON
THE NOSE OF DECENT MOISTURE TRANSPORT AND CONVERGENCE AT 925-850MB
LAYER TONIGHT INTO SATURDAY MORNING. THIS WILL CONTINUE TO SPREAD
RAIN/RAIN SHOWERS INTO THE FORECAST AREA THROUGH SATURDAY. ALONG
WITH THE SURGE OF MOISTURE...THE 03.12Z GFS/NAM ADVECT WARMER AIR
ALOFT INTO THE FORECAST AREA THIS EVENING AND INTO TONIGHT...WITH
925MB TEMPERATURES RISING TO PLUS 5 TO PLUS 13 DEGREES CELSIUS BY
12Z SATURDAY. ALL PRECIPITATION SHOULD REMAIN AS RAIN ACROSS THE
FORECAST AREA.
THE 03.12Z GFS/NAM INCREASE 0-6KM MOST UNSTABLE CAPE OF 300-500 J/KG
ACROSS SOUTHERN HALF OF FORECAST AREA AFTER 15Z SATURDAY. CANNOT
RULE OUT AN ISOLATED THUNDERSTORM ACROSS THIS AREA FROM 15Z
SATURDAY TO 00Z SUNDAY.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 255 PM CDT FRI MAY 3 2013
SUNDAY...EASTERLY TO NORTHEASTERLY FLOW ALOFT DEVELOPS OVER REGION
AFTER 06Z SUNDAY AND WILL ADVECT DRIER AIR INTO THE REGION. WITH
925MB TEMPERATURES AROUND PLUS 13 DEGREES CELSIUS AND PARTIAL
SUNSHINE OVER FORECAST AREA...EXPECT HIGH TEMPERATURES TO WARM INTO
THE 60S.
MONDAY NIGHT THROUGH FRIDAY...MAIN FORECAST CONCERNS ARE
PRECIPITATION CHANCES WEDNESDAY INTO FRIDAY. THE 03.00Z
GFS/ECMWF/GEM ARE IN AGREEMENT IN DEVELOPING SPLIT UPPER LEVEL FLOW
OVER THE CONTINENTAL UNITED STATES THROUGH PERIOD. THE MAIN
DIFFERENCE IS THE 03.00Z ECMWF PUSHES A WEAK UPPER LEVEL LOW INTO
THE UPPER MIDWEST WEDNESDAY INTO THURSDAY AND THE GEM/GFS CONTINUE
TO SHOW RIDGING OVER THE REGION. THE 03.00Z ECMWF INDICATE WEAK
MOISTURE CONVERGENCE AND LIFT IN ASSOCIATED WITH WEAK UPPER LEVEL
LOW AND PRODUCES PRECIPITATION OVER THE AREA. THE 03.00Z GEFS
INDICATE UPPER LEVEL RIDGING OVER THE UPPER MIDWEST AND GREAT LAKES
REGION AND NO HINT OF A WEAK UPPER LEVEL LOW OVER THE AREA.
CONFIDENCE IN PRECIPITATION CHANCES WEDNESDAY AND THURSDAY IS
DECREASING AT THIS TIME. THE 03.00Z GEM/ECMWF/GFS ARE SUGGESTING
850MB TEMPERATURES PLUS 6 TO PLUS 10 DEGREES CELSIUS MONDAY NIGHT
THROUGH FRIDAY ACROSS THE AREA. EXPECT HIGH TEMPERATURES TO
CLIMBING TO AROUND 70 ACROSS FORECAST AREA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 108 PM CDT FRI MAY 3 2013
WINTRY MIX FINALLY GIVING WAY TO ALL RAIN AT THE KRST/KLSE TAF
SITES AS WARMER AIR ROTATES IN FROM THE EAST/SOUTHEAST. LOOK FOR
AREAS OF RAIN/RAIN SHOWERS TO CONTINUE OVERNIGHT INTO SATURDAY
MORNING AS MOISTURE ROTATES AROUND LOW PRESSURE MEANDERING AROUND
SOUTHERN IL/MO. MVFR/IFR CIGS EXPECTED THROUGH THE PERIOD.
&&
.HYDROLOGY...
ISSUED AT 255 PM CDT FRI MAY 3 2013
THE RECENT HEAVY SNOW AND EXPECTED RAINFALL AMOUNTS OF THREE
QUARTERS OF AN INCH TO AROUND AN INCH OVER THE REGION TONIGHT INTO
SATURDAY NIGHT...WILL PRODUCE RISES ALONG THE MISSISSIPPI RIVER AND
AREA TRIBUTARIES THROUGH THE WEEKEND. A FEW SITES ALONG THE
MISSISSIPPI RIVER ARE EXPECTED TO RISE TO ABOVE AND TO NEAR FLOOD
STAGE. SOME TRIBUTARIES ARE FORECAST TO HAVE WITHIN BANK RISES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
255 PM CDT FRI MAY 3 2013
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION.....DAS
HYDROLOGY....DTJ