GOM: INVEST 90L

[JDawg12]

That's because they schedule recon a day in advance, and at that point a) it was still disorganised b) landfall still wasn't expected that quickly. They won't need to fly this mission in all likelihood, they won't find anything new. For all we know, they could fly out there and find a cold-core system.

yeah that's true

[Chacor]

06z SHIPS run

Code: Select all

                    *   ATLANTIC SHIPS INTENSITY FORECAST       *
                    *      GOES DATA AVAILABLE                  *
                    *      OHC  DATA AVAILABLE                  *
                    *      INVEST  AL902009  05/23/09  06 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120
V (KT) NO LAND    30    34    38    41    45    50    54    57    58    60    60    60    57
V (KT) LAND       30    34    38    33    30    28    27    27    27    28    29    29    30
V (KT) LGE mod    30    33    35    32    30    28    27    27    27    28    29    29    30

SHEAR (KT)         9    10    11    11    12    14    11    15    15    18    21    20    39
SHEAR DIR        262   213   195   182   166   160   185   152   194   172   198   209   246
SST (C)         26.3  26.3  26.3  26.0  24.9  21.8  19.8  18.2  17.1  16.0  14.3  11.3   6.5
POT. INT. (KT)   116   116   116   113   104    85    77    72    70    69    67    64    63
ADJ. POT. INT.   101   100   100    97    89    75    70    67    65    64    64    62    62
200 MB T (C)   -56.1 -56.7 -56.3 -55.7 -56.5 -56.7 -56.5 -57.2 -57.5 -57.7 -57.9 -58.5 -57.9
TH_E DEV (C)       6     4     7     7     4     7     4     5     0     2     0     0     0
700-500 MB RH     64    67    67    68    69    69    70    71    69    68    67    66    60
GFS VTEX (KT)     12    15    15    13    14    13    11    11     8     9     8     8     8
850 MB ENV VOR    61    61    66    61    53    53    17    56    57    74    43    85    70
200 MB DIV        17    26    37    66    39    61    16    33    45     3    40    37     4
LAND (KM)        103    43    28   -47  -128  -292  -439  -602  -737  -877  -999  -999  -999
LAT (DEG N)     28.6  29.3  30.0  30.8  31.5  33.0  34.2  35.5  36.7  38.0  39.5  40.9  41.5
LONG(DEG W)     88.4  88.8  89.1  89.4  89.7  90.6  91.4  92.3  92.6  92.7  91.8  90.3  88.0
STM SPEED (KT)     8     8     8     8     8     7     7     6     7     7     8     9     9
HEAT CONTENT       3     1     0     6     0     0     0     0     0     0     0     0     0

  FORECAST TRACK FROM BAMM      INITIAL HEADING/SPEED (DEG/KT):340/  7      CX,CY:  -1/  7
  T-12 MAX WIND:  25            PRESSURE OF STEERING LEVEL (MB):  706  (MEAN=624)
  GOES IR BRIGHTNESS TEMP. STD DEV.  50-200 KM RAD:  30.9 (MEAN=14.5)
  % GOES IR PIXELS WITH T < -20 C    50-200 KM RAD:  44.0 (MEAN=65.0)

                        INDIVIDUAL CONTRIBUTIONS TO INTENSITY CHANGE
                         6   12   18   24   36   48   60   72   84   96  108  120
                        ----------------------------------------------------------
  SAMPLE MEAN CHANGE     1.   2.   3.   4.   6.   8.   9.  11.  11.  12.  13.  13.
  SST POTENTIAL          0.   0.   0.   0.  -1.   0.   1.   3.   5.   4.   4.   5.
  VERTICAL SHEAR MAG     1.   3.   5.   7.   9.  11.  11.  11.  11.  10.   9.   5.
  VERTICAL SHEAR DIR     0.   0.   1.   1.   1.   2.   3.   4.   4.   5.   7.   9.
  PERSISTENCE            1.   1.   2.   2.   2.   2.   2.   2.   1.   1.   0.   0.
  200/250 MB TEMP.       1.   3.   4.   5.   8.  11.  14.  17.  20.  23.  25.  28.
  THETA_E EXCESS         0.  -1.  -1.  -2.  -3.  -4.  -6.  -9. -13. -16. -19. -23.
  700-500 MB RH          0.   0.   0.   0.  -1.  -1.  -2.  -2.  -2.  -3.  -3.  -3.
  GFS VORTEX TENDENCY    0.   1.   0.   1.   0.  -1.  -2.  -5.  -4.  -5.  -5.  -5.
  850 MB ENV VORTICITY   0.   0.   1.   1.   1.   1.   1.   2.   2.   3.   3.   3.
  200 MB DIVERGENCE      0.   0.   0.   1.   1.   1.   2.   2.   2.   2.   2.   2.
  ZONAL STORM MOTION     0.   0.   0.   0.   0.  -1.  -1.  -1.  -2.  -2.  -2.  -3.
  STEERING LEVEL PRES    0.   0.   0.   0.  -1.  -1.  -1.  -2.  -2.  -2.  -1.  -1.
  DAYS FROM CLIM. PEAK   0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.  -1.   0.  -1.
  GOES PREDICTORS       -1.  -1.  -2.  -2.  -3.  -3.  -3.  -2.  -2.  -2.  -2.  -2.
  OCEAN HEAT CONTENT     0.   0.   0.   0.   0.   0.  -1.  -1.  -1.  -1.   0.   0.
                        ----------------------------------------------------------
  TOTAL CHANGE           4.   8.  11.  15.  20.  24.  27.  28.  30.  30.  30.  27.

   ** 2009 ATLANTIC RI INDEX AL902009     INVEST 05/23/09  06 UTC **
           ( 30 KT OR MORE MAX WIND INCREASE IN NEXT 24 HR)
 
 12 HR PERSISTENCE (KT):   5.0 Range:-45.0 to  30.0 Scaled/Wgted Val:  0.7/  1.4
 850-200 MB SHEAR (KT) :  10.6 Range: 26.2 to   3.2 Scaled/Wgted Val:  0.7/  0.9
 D200 (10**7s-1)       :  37.0 Range:-21.0 to 140.0 Scaled/Wgted Val:  0.4/  0.5
 POT = MPI-VMAX (KT)   :  67.3 Range: 33.5 to 126.5 Scaled/Wgted Val:  0.4/  0.2
 850-700 MB REL HUM (%):  77.0 Range: 56.0 to  85.0 Scaled/Wgted Val:  0.7/  0.4
 % area w/pixels <-30 C:  41.0 Range: 16.0 to 100.0 Scaled/Wgted Val:  0.3/  0.1
 STD DEV OF IR BR TEMP :  30.9 Range: 30.6 to   3.2 Scaled/Wgted Val:  0.0/  0.0
 Heat content (KJ/cm2) :   2.0 Range:  0.0 to 130.0 Scaled/Wgted Val:  0.0/  0.0
 
 Prob of RI for 25 kt RI threshold=    17% is   1.3 times the sample mean(12.3%)
 Prob of RI for 30 kt RI threshold=     3% is   0.3 times the sample mean( 8.0%)
 Prob of RI for 35 kt RI threshold=     1% is   0.3 times the sample mean( 4.8%)

   ##         ANNULAR HURRICANE INDEX (AHI) AL902009     INVEST 05/23/09  06 UTC         ##
   ## STORM NOT ANNULAR, SCREENING STEP FAILED, NPASS=3 NFAIL=4                          ##
   ## AHI=  0   (AHI OF 100 IS BEST FIT TO ANN. STRUC., 1 IS MARGINAL, 0 IS NOT ANNULAR) ##
   ##     ANNULAR INDEX RAN NORMALLY             


[stormcloud]

Surface obs showing closed circulation.

[KWT]

I think given the look of this system I'd upgrade it anyway without recon, convection is pretty close to that circulation and its got a closed circulation which should do the job. I'd call this TD1 myself but its upto the NHC, going to be a close call whatever happens!

[Chacor]

Edit: WRONGTHREAD.

[aOl]

Mobile NWS thinks it's a tropical storm...


BULLETIN - IMMEDIATE BROADCAST REQUESTED
SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE MOBILE AL
230 AM CDT SAT MAY 23 2009

THE NATIONAL WEATHER SERVICE IN MOBILE HAS ISSUED A

* SPECIAL MARINE WARNING FOR...
WATERS FROM PENSACOLA FL TO PASCAGOULA MS FROM 20 TO 60 NM OVER
GULF OF MEXICO WATERS...
COASTAL WATERS FROM PENSACOLA FL TO PASCAGOULA MS OUT 20 NM OVER
GULF OF MEXICO WATERS...
INCLUDING MOBILE BAY...
LOCATIONS IN THIS WARNING INCLUDE BUT ARE NOT LIMITED TO ALABAMA
PORT...BATTLESHIP PARK...DAUPHIN ISLAND FISHING PIER...DOG RIVER
BRIDGE...EAST FOWL RIVER BRIDGE...FAIRHOPE PIER...FAREWELL
BUOY...FORT GAINES...FORT MORGAN...GULF SHORES PIER...MIDDLE BAY
LIGHT...MISSISSIPPI SOUND...PETIT BOIS PASS...WEEKS BAY AND WEST
END OF DAUPHIN ISLAND...

* UNTIL 430 AM CDT

* AT 222 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
CLUSTER OF THUNDERSTORMS...PRODUCING STRONG WINDS 34 KNOTS OR
GREATER 5 NM SOUTHEAST OF SOUTHEAST BANKS REEF...MOVING NORTHWEST
AT 20 KNOTS.

* THESE STRONG THUNDERSTORMS WILL BE OVER
COASTAL WATERS FROM PENSACOLA FL TO PASCAGOULA MS OUT TO 40 NM
INCLUDING MOBILE BAY THROUGH 430 AM CDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

MARINERS CAN EXPECT GUSTY WINDS...HIGH WAVES...DANGEROUS LIGHTNING...
AND HEAVY RAINS. BOATERS SHOULD SEEK SAFE HARBOR IMMEDIATELY...UNTIL
THIS STORM PASSES.


34 kt is tropical storm force.. and base velocities do indicate 43kt at about 4,000 feet, probably gusts of that force being brought down in stronger downdrafts.

[Chacor]

It just says it's producing 34 kt winds or stronger. Makes no mention about its structure or whether it's a tropical cyclone. It didn't actually mention "tropical storm", and for a good reason. It's a stretch to say that NWS Mobile is calling it a TS.

[aOl]

Well, I should have said if it's indeed tropical and the choice is between a TD or TS.

[cycloneye]

The 06 UTC Surface analysis from TAFB has the low at 1004 mbs.

[tailgater]

Looking at the Shortwave Sat. imagery the real center seems to be on eastern tip of the Miss. river delta. void of any T- storms So I'll say no Tropical storm or TD from this system.
http://www.ssd.noaa.gov/goes/east/gmex/loop-ir2.html
I just read this snippet from the Mobile AFD
216 FXUS64 KMOB 231015 AFDMOB AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOBILE AL 515 AM CDT SAT MAY 23 2009 SHORT TERM (TODAY AND TONIGHT) A WET AND BREEZY MORNING WILL CONTINUE ACROSS THE CENTRAL GULF COAST AS AN AREA OF LOW PRESSURE CURRENTLY LOCATED ABOUT 140 MILES SOUTH OF MOBILE CONTINUES TO TRACK NORTHWESTWARD. A COORDINATION CALL WITH THE NATIONAL HURRICANE CENTER THIS MORNING INDICATED THAT WHILE THE SYSTEM HAS BECOME SLIGHTLY BETTER ORGANIZED AND THEY HAVE NOW INDICATED A HIGH PROBABILITY THAT THE SYSTEM MAY REACH TROPICAL DEPRESSION STATUS BEFORE A LANDFALL ALONG THE MISSISSIPPI COAST BY AROUND 18Z TODAY... THAT THE MID LEVEL CENTER REMAINS SEPARATED FROM THE SFC CENTER AND SOME SHEAR IS CONTINUING TO KEEP DEEPER CONVECTION EAST OF THE PRIMARY SFC CENTER. AS A RESULT...NHC WILL NOT BE INITIATING ANY ADVISORIES DURING THE PREDAWN HOURS THIS MORNING. THEY DO INDICATE HOWEVER THAT THE SYSTEM COULD BECOME A TROPICAL DEPRESSION AT ANY TIME BEFORE MOVING INLAND LATER TODAY...SO THE SYSTEM SHOULD CONTINUE TO BE MONITORED. WHETHER THE SYSTEM DEVELOPS FURTHER OR NOT...WE WILL EXPERIENCE HEAVY RAIN...GUSTY WINDS AND ABOVE NORMAL TIDES TODAY. AS THE WINDS BECOME MORE SOUTHERLY TODAY DANGEROUS RIP CURRENTS WILL ALSO REMAIN LIKELY ALONG AREA BEACHES. HEAVY RAIN TO THE NORTH OF THE LOW WILL MOVE NORTHWARD ACROSS THE FCST AREA THIS MORNING. THE HEAVIEST RAINS ARE EXPECTED ACROSS SOUTHEAST MISSISSIPPI AND PORTIONS OF SOUTHWEST ALABAMA. RAINFALL AMOUNTS IN THIS AREA ARE EXPECTED TO RANGE FROM 2 TO 4 INCHES. A FLASH FLOOD WATCH HAS BEEN ISSUED THROUGH THIS AFTERNOON FOR THIS AREA AS ADDITIONAL HEAVY RAINS ARE POSSIBLE THROUGH THE DAY DEPENDING ON WHERE CONVERGENCE BANDS SET UP ON THE EASTERN SIDE OF THE LOW AS IT MOVES INLAND. CHANCES OF RAIN WILL DECREASE TO SCATTERED LATE TONIGHT AS THE LOW PRESSURE SYSTEM PULLS FARTHER AWAY TO THE NORTHWEST. CLOUDS AND RAIN WILL HOLD HIGH TEMPS DOWN INTO THE UPPER 70S TODAY WITH LOWS TONIGHT AROUND 70. 13/JC.12/DS

[Dionne]

Sever thunderstorm warning Mobile Bay and surrounding waters.

NWS Mobile reporting a >50% chance of system becoming a TD later today.

[HURAKAN]

I think the NHC is waiting for visible imaging before upgrading it.

[vegastar]

Looking at the Mobile short range radar it seems the circulation is tightning just before landfall:

http://radar.weather.gov/ridge/radar.php?product=NCR&rid=MOB&loop=yes

[HURAKAN]

First visible.

[HURAKAN]

AL, 90, 2009052306, , BEST, 0, 286N, 884W, 30, 1004, LO

[Dionne]

It's now obvious why we are under a "100% Heavy Rain" event today.

[HURAKAN]

[HURAKAN]

066
ABNT20 KNHC 231140
TWOAT
SPECIAL TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
740 AM EDT SAT MAY 23 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SATELLITE IMAGERY...RADAR DATA...AND SURFACE OBSERVATIONS INDICATE
THAT THE AREA OF LOW PRESSURE CENTERED OVER THE NORTH CENTRAL GULF
OF MEXICO ABOUT 75 MILES SOUTH OF MOBILE ALABAMA HAS CHANGED LITTLE
IN ORGANIZATION DURING THE LAST FEW HOURS. ADDITIONAL DEVELOPMENT
OF THIS SYSTEM IS BECOMING LESS LIKELY...SINCE THE CENTER WILL BE
MOVING ONSHORE LATER THIS MORNING OR EARLY AFTERNOON. THE AIR
FORCE RESERVE HURRICANE HUNTER AIRCRAFT MISSION SCHEDULED TO
INVESTIGATE THE LOW LATER TODAY HAS BEEN CANCELED. THERE IS NOW A
LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE BEFORE IT REACHES THE COAST LATER TODAY.
REGARDLESS OF DEVELOPMENT...HEAVY RAINS AND OCCASIONALLY GUSTY
WINDS ARE EXPECTED ALONG PORTIONS OF THE NORTH-CENTRAL AND
NORTHEAST GULF COAST THROUGH THE DAY...AND INTERESTS IN THIS AREA
SHOULD MONITOR THE PROGRESS OF THE SYSTEM.

ANOTHER SPECIAL OUTLOOK ON THIS SYSTEM WILL BE ISSUED THIS
AFTERNOON...IF NECESSARY.

$$
FORECASTER KIMBERLAIN/PASCH

[HURAKAN]

066
ABNT20 KNHC 231140
TWOAT
SPECIAL TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
740 AM EDT SAT MAY 23 2009

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SATELLITE IMAGERY...RADAR DATA...AND SURFACE OBSERVATIONS INDICATE
THAT THE AREA OF LOW PRESSURE CENTERED OVER THE NORTH CENTRAL GULF
OF MEXICO ABOUT 75 MILES SOUTH OF MOBILE ALABAMA HAS CHANGED LITTLE
IN ORGANIZATION DURING THE LAST FEW HOURS. ADDITIONAL DEVELOPMENT
OF THIS SYSTEM IS BECOMING LESS LIKELY...SINCE THE CENTER WILL BE
MOVING ONSHORE LATER THIS MORNING OR EARLY AFTERNOON. THE AIR
FORCE RESERVE HURRICANE HUNTER AIRCRAFT MISSION SCHEDULED TO
INVESTIGATE THE LOW LATER TODAY HAS BEEN CANCELED. THERE IS NOW A
LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE BEFORE IT REACHES THE COAST LATER TODAY.
REGARDLESS OF DEVELOPMENT...HEAVY RAINS AND OCCASIONALLY GUSTY
WINDS ARE EXPECTED ALONG PORTIONS OF THE NORTH-CENTRAL AND
NORTHEAST GULF COAST THROUGH THE DAY...AND INTERESTS IN THIS AREA
SHOULD MONITOR THE PROGRESS OF THE SYSTEM.

ANOTHER SPECIAL OUTLOOK ON THIS SYSTEM WILL BE ISSUED THIS
AFTERNOON...IF NECESSARY.

$$
FORECASTER KIMBERLAIN/PASCH

[HURAKAN]

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
805 AM EDT SAT MAY 23 2009

...SPECIAL FEATURE...
A 1004 MB SURFACE LOW IS LOCATED NEAR 30N89W...OR ABOUT 75 NM
SOUTH OF MOBILE ALABAMA. A SURFACE TROUGH EXTENDS FROM THE
SURFACE LOW TO THE NW YUCATAN PENINSULA NEAR 21N90W. LOW LEVEL
CONVERGENCE NEAR THE SURFACE LOW...ALONG WITH DIFFLUENCE
ASSOCIATED WITH A MIDDLE TO UPPER LEVEL TROUGH AXIS ACROSS THE
CENTRAL GULF ARE SUPPORTING NUMEROUS SHOWERS AND SCATTERED TSTMS
ACROSS THE GULF N OF 26N E OF 90W....INCLUDING THE NE GULF
COAST. THE SURFACE LOW IS FORECAST TO MOVE N-NW DURING THE NEXT
24 HOURS AND LOCATE INLAND OVER SWRN MISSISSIPPI. HOWEVER...
ADDITIONAL DEVELOPMENT OF THIS SYSTEM IS POSSIBLE...AND A
TROPICAL DEPRESSION COULD FORM BEFORE THE LOW MOVES INLAND OVER
THE NRN GULF COAST LATER TODAY. REGARDLESS OF DEVELOPMENT...
HEAVY RAINS AND OCCASIONALLY GUSTY WINDS ARE EXPECTED ALONG
PORTIONS OF THE NRN GULF COAST THROUGH THE REMAINDER OF
SATURDAY. INTERESTS IN THIS AREA SHOULD MONITOR THE PROGRESS OF
THE SYSTEM.