Barry Related NWS Forecast Discussions

[MWatkins]

Thought the afternoon update from the Miami forecast office was a pretty good synopsis of what is going on with what will soon be Barry. I know people tend to monitor information from their forecast offices so I figured this would be a good place to start a thread covering the analysis from the local offices.

Code: Select all

FXUS62 KMFL 011912
AFDMFL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MIAMI FL
312 PM EDT FRI JUN 1 2007

.SYNOPSIS...A DISTURBANCE CONTINUES TO MOVE OUT OF THE CARIBBEAN SEA
AND ACROSS THE SOUTHEAST GULF OF MEXICO ALONG WITH ASSOCIATED SHOWER
AND THUNDERSTORM ACTIVITY WHILE AN UPPER LEVEL TROUGH SLOWLY PUSHES
EAST ACROSS THE WESTERN GULF.


&&

.DISCUSSION...A LARGE PLUME OF MOISTURE CONTINUES TO SURGE OUT OF
THE CARIBBEAN AND INTO SOUTH FLORIDA AS A TROPICAL DISTURBANCE MOVES
NORTHEAST AND INTO THE CENTRAL PORTION OF THE STATE TONIGHT /
SATURDAY MORNING. THE EASTERN SIDE OF THE DISTURBANCE IS BEING AIDED
BY UPPER LEVEL DIVERGENCE THAT IS A COMBO FROM THE UPPER LEVEL
TROUGH OVER THE WESTERN GULF THAT IS CENTERED SOUTH OF LOUISIANA AND
AN UPPER LEVEL RIDGE FROM CENTRAL AMERICA TO FLORIDA THAT IS
CENTERED IN THE NORTHWEST CARIBBEAN. BASICALLY THIS IS ALLOWING
ENOUGH DIVERGENCE ALOFT TO KEEP CONVECTION AND WIDESPREAD RAIN
INITIATED, BUT ALSO KEEPING THE SHEAR HIGH ENOUGH THAT THE THE
DISTURBANCE IS HAVING A HARD TIME ORGANIZING. THIS ALSO ALLOWS THE
MUCH NEEDED RAIN TO SPREAD INTO SOUTH AND CENTRAL FLORIDA THIS
EVENING, BUT BEING THAT THE AIRMASS WILL BE GREATLY MOISTENING UP
THIS EVENING AND THAT TROPICAL SYSTEMS ARE PROLIFIC RAIN PRODUCERS
HEAVY RAIN WILL BE POSSIBLE. BOTTOM LINE ITS A ASYMMETRIC SYSTEM
THAT POSSES LITTLE WIND THREAT AND MUCH NEEDED RAIN RELIEF.

FOR THE FORECAST... STICKING CLOSE TO THE GFS WITH THE DISTURBANCE /
LOW CENTER MOVING INTO THE CENTRAL PORTIONS OF THE WEST COAST AND
INTO THE ATLANTIC ON SATURDAY MORNING AS OPPOSED TO THE NAM SOLUTION
OF MOVING NORTHBOUND INTO THE FL PANHANDLE SATURDAY EVENING. THE GFS
SEEMS TO HAVE INITIALIZED BETTER AND MOST OTHER MODELS ARE ALSO
CLUSTERED CLOSE TO THE GFS AS WELL. IT IS ALSO MORE LIKELY THAT THE
LOW CENTER WOULD BE PULLED ALONG WITH THE MID LEVEL FLOW WHICH IS
OUT OF THE SOUTHWEST IN THE SOUTHEASTERN GULF AS LONG AS DECENT
CONVECTION REMAINS ONGOING NEAR THE CENTER.

THE GFS AND THE SLIGHTLY DRIER NAM`S (AT LEAST FOR SOUTH FL)
SOUNDINGS RANGE FROM 2.6 TO 2.3 INCHES OF PWAT RESPECTIVELY THAT IS
ROUGHLY 3 TO 2 STANDARD DEVIATIONS ABOVE THE NORM BY THIS EVENING.
THIS MEANS THAT THERE IS THE POSSIBILITY THAT SOME POORLY DRAINED
AREAS MAY EXPERIENCE SOME MINOR FLOODING WITH SOME ISOLATED TOTALS
POSSIBLY REACHING TO AROUND 5 INCHES, BUT DUE TO THE AREA RECENTLY
BEING BEING SO DRY NO FLOOD WATCHES WILL BE ISSUED.

AS FOR THE WINDS, IT`S A TOUGH CALL. THE COASTAL SECTIONS MAY BE
CLOSE TO MEETING WIND ADVISORY CRITERIA TONIGHT AND SATURDAY
MORNING, BUT AT THIS TIME WILL HOLD OFF ON THE CALL TO WAIT AND
SEE ANY INFO THAT IS COMING OUT OF NHC AND TAFB THIS EVENING.

AFTER THIS SYSTEM PASSES THE RAIN CHANCES ARE EXPECTED TO DECREASE,
BUT A RETURN TO SUMMERTIME DIURNAL THUNDERSTORMS WILL COMMENCE AS
WEAK HIGH PRESSURE BUILDS IN.

MW

[MWatkins]

Here is the discussion out of the Melbourne office (they do a really good job with these):

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FXUS62 KMLB 011841
AFDMLB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
240 PM EDT FRI JUN 1 2007

.DISCUSSION...

...RAIN ON THE WAY TONIGHT INTO SATURDAY...
...INCREASING WINDS ACROSS THE ATLANTIC AND BEACHES OVERNIGHT...

CURRENTLY/TONIGHT...SFC CIRCULATION CENTER HAS EMERGED ACROSS THE SE
GULF OF MEXICO THIS AFTERNOON MOVING TO THE NNE. CONSENSUS OF THE
MORE RELIABLE MODELS WITH THIS SYSTEM AGREE THAT THE MID/UPR LVL
TROUGH TO THE WEST WILL PICK UP THE LOW AND MOVE IT NNE/NE
THROUGH TONIGHT. THIS WILL ALLOW TROPICAL MOISTURE TO PE PULLED
NORTHWARD FROM S FL OVER CENTRAL FL LATER TONIGHT. WILL CONTINUE
CATEGORICAL RAIN CHANCES WITH MANY AREAS RECEIVING A HALF TO ONE
INCH OVERNIGHT WITH SOME HEAVIER 2 INCH AMOUNTS POSSIBLE. ALONG WITH
THE THREAT FOR HEAVY RAINFALL THERE WILL BE A LOW THREAT FOR
ISOLATED TORNADOES WITH DISCRETE CELLS THAT DEVELOP TO THE EAST AND
NORTHEAST OF THE LOW CENTER. HELICITY WILL BE MAXIMIZED NORTH OF THE
PSEUDO WARM FRONT BUT INSTABILITY WILL BE THE QUESTION MARK. GFS
DOES SHOW LWR 70S DWPTS MAKING IT INTO SRN SECTIONS LATE BUT THIS IS
ALSO ON THE HEELS OF 40-50KT LOW LVL SSE INFLOW AT H9 THAT MAY NOT
MATERIALIZE. AS THE LOW MOVES CLOSER TO THE AREA RESULTING
PRESSURE GRADIENT WILL INCREASE WITH BREEZY CONDITIONS TO WINDY
ALONG THE IMMEDIATE COAST AND BEACHES. WILL LET LAKE WIND ADVISORY
CONTINUE THROUGH 8PM AND HAVE EVENING SHIFT TAKE A LOOK A NEED FOR
ANY CSTL WIND ADVISORIES.

SAT...MODELS CONTINUE TO BE IN DISAGREEMENT WITH REGARD TO THE TRACK
AND SPEED OF THE LOW PRESSURE SYSTEM IN THE EASTERN GULF OF MEXICO.
NEVERTHELESS...CONFIDENCE IS HIGH THAT GREATEST COVERAGE OF
PRECIPITATION AND MOST ACTIVE WEATHER WILL BE LOCATED EAST OF THE
CENTER AND ACROSS THE FL PENINSULA. WILL AGAIN FOLLOW MORE OF A
CONSENSUS APPROACH...WHICH PLACES THE WARM FRONT ACROSS THE FORECAST
AREA EARLY SAT. THE THREAT FOR TORNADOES WILL BE ELEVATED DURING THE
MORNING AS LOW-LEVEL SHEAR IS MAXIMIZED ALONG THE NORTHWARD MOVING
BOUNDARY. HOWEVER...LIMITED INSTABILITY SUGGESTS THE POTENTIAL FOR
STRONG UPDRAFTS AND SUBSEQUENT ROTATION WILL BE LOW.

ALTHOUGH THE EXACT DETAILS OF THE GFS MAY NOT BE ENTIRELY ACCURATE
DUE TO QPF-SURFACE PRESSURE FEEDBACK PROBLEMS...IT SHOULD NOT BE
DISCOUNTED ENTIRELY. PERSISTENCE IN THE GFS LENDS CREDENCE TOWARDS A
FASTER SOLUTION. AT THE VERY LEAST...THE SOUTHEASTERN PORTION OF THE
FORECAST AREA WILL BECOME POSITIONED IN THE WARM SECTOR DURING THE
AFTERNOON AS THE CENTER OF THE LOW MOVES ACROSS THE STATE AND INTO
THE ATLANTIC. ALTHOUGH THE CHANCE FOR WIDESPREAD PRECIPITATION WILL
DIMINISH...THE THREAT FOR SCATTERED CONVECTION WILL INCREASE. ANY
BACKING TO THE LOW-LEVEL FLOW ALONG THE SPACE AND TREASURE COASTS
WILL AGAIN ENHANCE THE THREAT FOR ISOLATED TORNADOES IN THE
STRONGEST STORMS.

SAT NIGHT...DEEPEST MOISTURE WILL SLIDE NORTH AND EAST OF FORECAST
AREA...THOUGH THE THREAT FOR ADDITIONAL SHOWER ACTIVITY WILL
CONTINUE INTO THE EVENING AS THE UPPER TROUGH MOVES ACROSS THE
STATE. PRECIPITATION WILL LIKELY DIMINISH IN COVERAGE AND INTENSITY
DURING THE LATE EVENING AS A DRIER AND MORE STABLE AIR MASS BUILDS
INTO THE AREA.

[JonathanBelles]

000
FXUS62 KTBW 011737
AFDTBW

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TAMPA BAY RUSKIN FL
137 PM EDT FRI JUN 1 2007

...WELCOME RAINS ON THEIR WAY...

.SYNOPSIS...SUBTROPICAL JET STREAM OVER THE CENTRAL GULF HAVING THE
EXPECTED EFFECT ON THE LOW PRESSURE SYSTEM NOW CENTERED WEST OF
CUBA. HIGH PRESSURE THAT HAS BEEN OVER THE EASTERN SEABOARD HAS
SHIFTED EAST INTO THE ATLANTIC WITH GRADIENT TIGHTENING AS LOW
APPROACHES.

&&

.SHORT TERM (TONIGHT-SUNDAY)...MODELS CONTINUE TO BE ALL OVER THE
PLACE WITH REGARD TO HYBRID LOW SYSTEM APPROACHING THE AREA. GIVEN
INCONSISTENCIES PREFER TO STAY IN LINE WITH PREVIOUS FORECAST
THINKING...WHICH MATCHED UP WELL WITH THE ECMWF AND THE UKMET. THIS
FORECAST BRINGS THE BULK OF THE RAIN AND ANY WINDY WEATHER WELL
AHEAD OF THE SYSTEM FROM NOW THROUGH SATURDAY. ANY STORMS OR
STRONGER SHOWERS THAT DEVELOP COULD BRING POTENTIAL FOR BRIEF GUSTY
WINDS AS WE`VE BEEN ADVERTISING...40-50 MPH...AND RAINFALL TOTALS
AREAWIDE EXPECTED TO AVERAGE BETWEEN 2 AND 3 INCHES. ALSO CANNOT
RULE OUT AN ISOLATED TORNADO GIVEN FAVORABLE SHEAR PROFILE ACROSS
THE REGION TONIGHT INTO EARLY SATURDAY.

SATURDAY AFTERNOON...EXPECTING THE LOW TO BE CENTERED JUST WEST OF
TAMPA BAY WITH THE HEAVIEST RAINS OVER THE NORTHERN CWA. WINDS WILL
SHIFT AROUND TO THE NORTHWEST AS THE LOW DEPARTS SATURDAY EVENING.
CURRENTLY NOT FORECASTING ANY COASTAL FLOODING...AS COASTAL SITE
FORECASTS ARE ONLY SHOWING AT MOST A SURGE OF 1 FOOT. WILL HAVE TO
MONITOR FOR CHANGES AS WELL AS FOR TIMING WITH ASTRONOMICAL HIGH
TIDES...ESPECIALLY SOUTH OF THE TAMPA BAY AREA.

SUNDAY ONLY HAVE ISOLATED STORMS IN THE FORECAST AS THE LOW WILL BE
WELL NORTHEAST OF THE REGION AND EXPECTING DRIER AIR TO BE WRAPPING
AROUND THE BACK SIDE OF THE LOW. WITH TEMPERATURES WARMING UP UNDER
SUNNIER SKIES AND FLOW MOVING IN OFF THE GULF...EXPECT MUGGY AND
UNCOMFORTABLE CONDITIONS DURING THE DAY.

.LONG TERM (SUNDAY NIGHT - FRIDAY)...UPPER TROUGH AND DEEPENING SURFACE
LOW WILL MOVE NORTHEAST UP ALONG THE MID ATLANTIC COAST SUNDAY NIGHT.
ON MONDAY ZONAL FLOW ALOFT WITH WEAK SURFACE HIGH PRESSURE TO THE SOUTH
OF THE STATE WILL FAVOR AN ONSHORE SOUTHWEST TO WESTERLY WIND FLOW WITH
WARM AND MUGGY CONDITIONS...WITH ISOLATED SHOWERS OR STORMS BEST CHANCES
OVER INTERIOR LOCATIONS. ANOTHER UPSTREAM SHORT WAVE TROUGH WILL SWING
ACROSS THE SOUTHEASTERN U.S. ON TUESDAY WITH AN ATTENDANT COLD FRONT
MOVING INTO THE NORTHERN PENINSULA AND STALLING OUT...WHILE SURFACE
HIGH PRESSURE REMAINS ACROSS THE FLORIDA STRAITS. DEEPER MOISTURE AXIS
ASSOCIATED WITH THE FRONT WILL SUPPORT LOW END SCATTERED RANGE POPS
(~30%) FROM THE NATURE COAST NORTH...WHILE MUGGY CONDITIONS AND DAYTIME
HEATING WILL CONTINUE TO SUPPORT 20% POPS ACROSS THE REMAINDER THE
FORECAST AREA. UPPER RIDGING BUILDS OVER THE SOUTHERN PENINSULA AND GULF
WITH THE ATTENDANT SURFACE HIGH LIFTING NORTH TO THE NORTH CENTRAL
PENINSULA LATE WEDNESDAY THROUGH FRIDAY. AS THE HIGH LIFTS TO THE NORTH
OVERALL FLOW WILL BECOME SOUTHEAST WHICH WILL FAVOR ABOVE NORMAL TEMPS
WITH SOME DIURNAL CONVECTION (POPS 20-30%) DEVELOPING ALONG THE SEA
BREEZE CIRCULATIONS DURING THE AFTERNOON AND EARLY EVENING HOURS. ONSHORE
FLOW AT THE START OF THE LONG TERM WILL KEEP TEMPS NEAR NORMAL ALONG
THE IMMEDIATE COAST DURING MONDAY AND TUESDAY...THEN ABOVE NORMAL
READINGS ARE EXPECTED EVERYWHERE WEDNESDAY-FRIDAY AS THE FLOW BECOME
SOUTHEASTERLY. 12Z MEX NUMBERS ARE SIMILAR TO PREVIOUS RUNS...SO WILL
USE A BLEND.

[Recurve]

Posted this in the Florida obs thread, but thought it'd belong here too, mentions lower keys tornado

AREA FORECAST DISCUSSION FOR THE FLORIDA KEYS
NATIONAL WEATHER SERVICE KEY WEST FL
551 PM EDT FRI JUN 1 2007

.DISCUSSION...
TROPICAL STORM BARRY DEVELOPED LATE THIS AFTERNOON OVER THE
SOUTHEASTERN GULF OF MEXICO AND IS EXPECTED TO REMAIN A TROPICAL
STORM AS IT ACCELERATES TOWARD THE NORTH-NORTHEAST TONIGHT AND
SATURDAY. THE FLORIDA KEYS WILL REMAIN ON THE EASTERN AND SOUTHERN
FRINGES OF THIS SYSTEM...WHERE WE WILL RECEIVE ADDITIONAL BENEFICIAL
RAINFALL OVER THE NEXT 36 HOURS. A WARM FRONT/THETA-E GRADIENT HAD
MOVED NORTH THROUGH THE KEYS EARLIER THIS AFTERNOON...AS THE LOW
PRESSURE SYSTEM TO OUR WEST WAS TRANSITIONING INTO TROPICAL STORM
BARRY. ALTHOUGH ONLY WEAK CONDITIONAL INSTABILITY WAS PRESENT...A
MODERATELY SHEARED ENVIRONMENT HAD DEVELOPED IN THE BOUNDARY LAYER
ALONG THE WARM FRONT...AND APPARENTLY...A WEAK WATERSPOUT-TORNADO
FORMED BENEATH A SHALLOW...ROTATING CONVECTIVE CELL SOUTH OF THE
LOWER KEYS...THEN MOVED NORTHWEST ALONG AN OUTFLOW BOUNDARY FROM AN
ADJACENT CELL...AND THROUGH PORTIONS OF SUGARLOAF KEY. ONE HOME
SUSTAINED SOME ROOF AND PORCH DAMAGE FROM THE TORNADO. NO LIGHTNING
OR THUNDER HAS BEEN OBSERVED IN THE KEYS TODAY. HOWEVER...WIDESPREAD
RAIN HAS PRODUCED UP TO 2 INCHES OF RAINFALL IN SOME ISLAND
COMMUNITIES.

CURRENTLY...AIR TEMPERATURES ARE NEAR DAYTIME HIGHS...IN THE UPPER
70S...WITH DEWPOINTS IN THE MID 70S. A BREAK IN THE STRATIFORM RAIN
IS EVIDENT OVER THE LOWER KEYS AND WATERS BETWEEN THE LOWER KEYS AND
CUBA. LONGER-RANGE DOPPLER RADAR SCANS OUT OF KEY WEST SHOW MORE RAIN
AND SOME THUNDERSTORMS DEVELOPING IN A BAND OVER THE SOUTHEASTERN
GULF OF MEXICO AND WESTERN CUBA.

FORECASTS -- RAIN IS EXPECTED TONIGHT...WITH THUNDERSTORMS BECOMING
MORE LIKELY AS LOW-LEVEL TRAJECTORIES BECOME ROOTED IN AIR
ORIGINATING IN THE CARIBBEAN TROPICS. MORE RAIN AND STORMS ARE
EXPECTED SATURDAY...ESPECIALLY EARLY...IN LOW-LEVEL CONFLUENT FLOW
SOUTH OF TROPICAL STORM BARRY. THEN...THE ATLANTIC RIDGE WILL
GRADUALLY MOVE OVER...AND THEN NORTH OF...THE FLORIDA KEYS NEXT
WEEK...WITH A SUBSEQUENT RETURN TO FAIRER WEATHER.
&&

.MARINE...
SMALL CRAFT ADVISORIES REMAIN IN EFFECT FOR ALL ZONES. STRONG EAST TO
SOUTHEAST BREEZES WILL PERSIST TONIGHT...TURNING TO SOUTH BY
DAYBREAK. STRONG SOUTH BREEZES WILL EVENTUALLY TURN SOUTHWEST AND
DECREASE TO NEAR 15 KNOTS BY SUNDAY. WIDESPREAD RAIN...NUMEROUS
SHOWERS...AND ISOLATED THUNDERSTORMS ARE EXPECTED TONIGHT AND
SATURDAY...GRADUALLY TAPERING OFF TO ISOLATED BY SUNDAY NIGHT OR
MONDAY.
&&

.AVIATION...
MVFR TO VFR CONDITIONS CAN BE EXPECTED ALONG THE KMIA TO KEYW TWEB
ROUTE...AND AT THE ISLAND TERMINALS THIS EVENING AS LIGHT TO
MODERATE RAIN WITH EMBEDDED HEAVIER SHOWERS WILL PREVAIL. CEILINGS
WILL GENERALLY RANGE BETWEEN 2500 AND 4000 FT. OCCASIONAL HEAVIER
SHOWERS WILL PRODUCE PERIODS OF IFR CONDITIONS. SURFACE WINDS AT THE
KEYW AND KMTH TERMINALS WILL BE SOUTHEAST AT 15 TO 20 KNOTS AND
GUSTY...AND THEN SHIFT TO THE SOUTH SOUTHEAST DURING THE OVERNIGHT
HOURS.
&&

.PRELIMINARY POINT TEMPS/POPS...
KEY WEST 75 81 76 82 / 100 70 50 30
MARATHON 75 83 76 84 / 100 70 50 30
&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GM...SMALL CRAFT ADVISORY FOR GMZ031-GMZ032-
GMZ033-GMZ052-GMZ053-GMZ054-GMZ072-GMZ073-GMZ074-GMZ075.

&&

$$

K. KASPER
AL
L. KASPER
A. GILSTAD

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