NWS Discussion on TD10 and NAM/GFS Models

[N2FSU]

From the Tallahassee Area Forecast Discussion:

.LONG TERM...THURSDAY THROUGH SUNDAY...AS THE BOUNDARY BEGINS TO
WASH OUT ON THURSDAY WILL KEEP 50 POPS IN FORECAST AREA WIDE. FOCUS
THEN WILL BE SHIFTING TO WHAT WILL HAPPEN WITH TROPICAL WAVE NEAR
THE BAHAMAS. ONE THING IS CLEAR. TROPICAL MOISTURE WILL BE ON THE
INCREASE INTO THE WEEKEND. IF YOU BELIEVE THE NAM...A RATHER POTENT
LOW PRESSURE AREA WILL BE OFF THE FLORIDA EAST COAST BY FRIDAY
MORNING. HOWEVER...THE NAM ALWAYS SEEMS TO HAVE DIFFICULTY WITH
TROPICAL SYSTEMS...ESPECIALLY THIS SEASON. AND...AS HPC HAS NOTED
THE NAM IS ONE OF THE FURTHEST RIGHT OUTLIERS AND HAS BEEN SUCH
THROUGH THE LAST COUPLE OF DAYS. FOR THESE REASONS THE NAM SOLUTION
HAS BEEN DISCOUNTED AT THIS TIME. THE GFS IS ON THE OTHER SIDE OF
THE COIN WITH A VERY WEAK NON-CLOSED LOW MOVING THROUGH THE FLORIDA
STRAITS AND THEN MEANDERING IN THE GULF THROUGH THE WEEKEND AND
EARLY PART OF NEXT WEEK. DON'T REALLY LIKE THE GFS SOLUTION AS THERE
HAS BEEN LIMITED CONTINUITY FROM RUN TO RUN IN THE GFS. AT THIS
POINT...REALLY DO NOT HAVE THE CONFIDENCE TO STRAY TO FAR FROM
GUIDANCE VALUES. THUS...SAFEST AND BEST BET IS TO ALLOW POPS TO
REMAIN NEAR CLIMATOLOGY OF 30 TO 40 PERCENT. WILL CARRY 40 PERCENT
POPS OVER MAINLY FLORIDA AND OUR EASTERN GA ZONES WHERE CHANCES OF
RAIN WILL BE HIGHER DUE TO PROXIMITY OF THE TROPICAL WAVE.
OVERALL...VERY FEW CHANGES WERE MADE TO THE EXTENDED GRIDS.

[TampaFl]

FXUS62 KMLB 231354
AFDMLB

EAST CENTRAL FLORIDA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MELBOURNE FL
954 AM EDT TUE AUG 23 2005

.DISCUSSION...
SUBSIDENCE ASCD WITH UPPER RIDGE OVER STATE CONTINUES TO PRODUCE MID
LEVEL DRYING WITH ASCD WARMING ALOFT. A SWATH OF HIGHER MOISTURE IS
SET TO WORK INTO THE AREA DURING THE DAY FROM THE SE AS EVIDENCED BY
MORNING SOUNDINGS @ MIAMI AND NASSAU IN DEEPENING SE FLOW. MARINE
SHOWERS OVER THE TREASURE COAST SIGNAL THIS ARRIVAL. SCATTERED
COVERAGE OF STORMS DURING THE PEAK AFTERNOON HOURS INTO THE EVENING
LOOKS GOOD. DEEP LAYER ELYS WILL PUSH ACTIVITY TOWARD THE WESTERN
PENINSULA THIS EVENING. A FEW STRONG STORMS WILL POSSIBLE OVER
INTERIOR SECTIONS DUE TO MID LEVEL DRY LAYER. WL UPDATE ZONES MAINLY
WITH TWEAKS TO TEMPORAL WORDING.

DEEP CONVECTION OVER SE BAHAMAS SHOWING INCREASED SIGNS OF
ORGANIZATION AND AIRCRAFT ARE SET TO INVESTIGATE SYSTEM EARLY THIS
AFTERNOON. WE SHOULD KNOW MORE ABOUT SYSTEM AND ITS POTENTIAL
EFFECTS BY THE AFTERNOON PKG.

&&

.MARINE....LOW LEVEL RIDGE ACROSS CENTRAL FLORIDA KEEPING NORTHERN
LEG MORE WITH A SOUTH WIND. RIDGE FORECAST TO NUDGE NORTHWARD BUT
MODELS PROBABLY A LITTLE TOO FAST. ONLY MINOR TWEAKS TO THE RATHER
TYPICAL LOOKING LATE AUGUST FORECAST (WINDS 10 KNOTS OR LESS, SEAS
LESS THAN 3 FEET).

&&

.AVIATION...SCT SHRA WITH ISOLD TSRA REDUCING CIGS TO IFR AFT 18Z.
COASTAL SHOWERS THIS MORNING SOUTH OF VRB WL PRODUCE ISOLD MVFR/IFR
CONDS TIL 17Z.

CLIMATE...ORLANDO INTERNATIONAL AIRPORT IS APPROACHING THE RECORD
FOR CONSECUTIVE DAYS WITH TEMPERATURES REACHING 90 DEGREES OR
HIGHER. THE PERIOD OF JULY 11 TO AUGUST 22 THIS YEAR (43 DAYS)
STILL TRAILS THE RECORD OF 46 CONSECUTIVE DAYS SET IN 1981 (JULY 2
TO AUG 16).

A TROPICAL WAVE IS FORECAST TO APPROACH THE AREA BY LATE WEEK...
WHICH MAY ACT TO PRODUCE A DAY WHERE RAINFALL OCCURS EARLIER THAN
NORMAL...AND CLOUDINESS LIMITS DAYTIME HEATING SOMEWHAT. THEREFORE
IT IS LIKELY TO BE A CLOSE CALL AS TO WHETHER THE RECORD WILL BE
BROKEN OR NOT.

&&

.MLB WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$

SHORT TERM...PENDERGRAST
LONG TERM....LASCODY