Felicia not weakening; new African wave may develop
Hurricane Felicia has not weakened today, and continues to hold its own in spite of cool sea surface temperatures beneath it. Recent satellite imagery shows that the tops of thunderstorms surrounding the eye have cooled slightly, indicating that the updrafts sustaining the eyewall are maintaining their strength. The appearance of the hurricane has improved some today, with the storm assuming a more symmetric appearance.
Figure 1. Current satellite image of Hurricane Felicia.
Sea surface temperatures (SSTs) under Felicia have now fallen to 24.7°C, well below the 26°C threshold typically needed to sustain a hurricane. SSTs will slowly increase to 26°C by the time the storm reaches Hawaii, though. Wind shear is expected to remain low to moderate, 5 - 15 knots, through Monday morning. By Monday night, shear will rise to 20 knots, and remain above 20 knots thereafter. The higher shear combined with the relatively cool SSTs should mean that Felicia will be rapidly weakening in its final 24 hours before reaching Hawaii. Several of the computer models continue to show that this shear will be high enough to tear Felicia apart before it reaches Hawaii, though it appears to me that Felicia's current strength and annular structure will help it resist the shear enough to allow the storm to hit Hawaii as a tropical depression with 35 mph winds. Regardless, Felicia will bring heavy rain Hawaii beginning on Monday morning, and these rains will have the capability of causing flash floods and mudslides. The Hurricane Hunters are scheduled to make their first low-level investigation of Felicia this afternoon (around 10 am Hawaiian time). The NOAA jet also flies into Felicia today, and will drop a series of dropsondes that will be used to gather data that will be fed into today's 12Z and 00Z computer model runs.
Typhoon Morakot hits Taiwan
Typhoon Morakot hit Taiwan yesterday, battering the island with Category 1 winds and heavy rain. The Taipei airport recorded sustained winds of 56 mph, gusting to 76 mph, at the peak of the storm. Morakot killed 6 on Taiwan and 10 in the Philippines, and is headed towards a final landfall on mainland China as a tropical storm later today. Storm chaser James Reynolds intercepted the storm and posted videos on typhoonfury.com and Youtube. Morakot is still visible today on Taiwan radar.
Figure 2. Visible satellite image of a spinning tropical wave leaving the coast of Africa. The image was taken at 8am EDT 8/8/09.
African tropical wave may develop
A strong tropical wave with a moderate amount of spin is moving off the coast of Africa this morning. The wave is under about 10 - 20 knots of wind shear and has sea surface temperatures beneath it of 27°C. These conditions are probably too marginal to allow development over the next two days. As the wave moves westward away from Africa over the next few days, wind shear should slowly decrease and the SSTs will warm, potentially allowing for some slow development. The UKMET, GFS, and NOGAPS models all indicate the possibility that this will become a tropical depression 3 - 5 days from now. The ECMWF model forecasts that strong easterly winds over the wave will create too much shear to allow development. The wave is well south of the Saharan Air Layer, so dry air and African dust should not interfere over the next 3 - 5 days. I give the wave a medium (30 - 50% chance) of developing into a tropical depression in the next seven days.
I'll have an update on Sunday.
Jeff Masters
Reader Comments
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Will he stop doing the polls?
A. Yes
B. No
C. Maybe
D. On Tuesday
LOL!
We don't know.
Too early too tell. It could curve out to sea or end up in the Caribbean.
for what?
I would say we should have an invest tomorrow and a depression on Monday or Tuesday
and it looks like our wave at 55W gave up since it isn't developing any new convection yet
what?
WTPA32 PHFO 090257
TCPCP2
BULLETIN
HURRICANE FELICIA ADVISORY NUMBER 22
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP082009
500 PM HST SAT AUG 08 2009
...FELICIA MARCHING WESTWARD...TROPICAL STORM WATCHES ISSUED...
AT 500 PM HST...0300 UTC...A TROPICAL STORM WATCH HAS BEEN ISSUED
FOR THE BIG ISLAND OF HAWAII...AND FOR ALL OF MAUI COUNTY...WHICH
INCLUDES THE ISLANDS OF MAUI...KAHOOLAWE...LANAI...AND MOLOKAI.
A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN THE NEXT 48 HOURS.
INTERESTS IN THE REMAINDER OF THE STATE OF HAWAII...INCLUDING THE
ISLANDS OF OAHU...KAUAI...AND NIIHAU...SHOULD CLOSELY MONITOR
THE PROGRESS OF FELICIA. A TROPICAL STORM WATCH COULD BE REQUIRED
FOR THESE AREAS LATER TONIGHT.
AT 500 PM HST...0300 UTC...THE CENTER OF HURRICANE FELICIA WAS
LOCATED NEAR LATITUDE 20.1 NORTH...LONGITUDE 143.4 WEST OR ABOUT
760 MILES EAST OF HILO HAWAII AND ABOUT 940 MILES...EAST OF
HONOLULU HAWAII.
FELICIA IS MOVING TOWARD THE WEST NEAR 15 MPH AND THIS GENERAL
MOTION IS EXPECTED TO CONTINUE FOR THE NEXT COUPLE OF DAYS. ON THIS
TRACK...FELICIA IS EXPECTED TO BE NEAR OR OVER THE HAWAIIAN
ISLANDS BY MONDAY.
MAXIMUM SUSTAINED WINDS ARE NEAR 85 MPH WITH HIGHER GUSTS. FELICIA
IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON SCALE. SLOW
WEAKENING IS FORECAST DURING THE NEXT COUPLE OF DAYS...AND FELICIA
COULD BECOME A TROPICAL STORM WITHIN THE NEXT 24 HOURS.
HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 35 MILES FROM THE
CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES.
THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON RECENT AIR FORCE
RECONNAISSANCE DATA IS 982 MB...29.00 INCHES.
...SUMMARY OF 500 PM HST INFORMATION...
LOCATION...20.1N 143.4W
MAXIMUM SUSTAINED WINDS...85 MPH
PRESENT MOVEMENT...WEST OR 280 DEGREES AT 15 MPH
MINIMUM CENTRAL PRESSURE...982 MB
AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE CENTRAL PACIFIC
HURRICANE CENTER AT 800 PM HST FOLLOWED BY THE NEXT COMPLETE
ADVISORY AT 1100 PM HST.
$$
FORECASTER KNABB/R BALLARD
WTPA42 PHFO 090258
TCDCP2
HURRICANE FELICIA DISCUSSION NUMBER 22
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP082009
500 PM HST SAT AUG 08 2009
THE SATELLITE PRESENTATION OF FELICIA HAS NOT CHANGED APPRECIABLY
SINCE THE LAST AIR FORCE RECONNAISSANCE FIX AT ABOUT 2330 UTC...
WHEN THE CENTRAL PRESSURE WAS MEASURED AT 982 MB. THE EARLIER
FLIGHT-LEVEL WINDS OF 85 KT AT 700 MB AROUND 2000 UTC...
CORRESPONDING TO ABOUT 76 KT AT THE SURFACE...ALONG WITH DVORAK CI
NUMBERS OF 4.5...PROVIDE THE BASIS FOR MAINTAINING THE ADVISORY
INTENSITY AT 75 KT. UPPER-LEVEL OUTFLOW APPEARS SLIGHTLY
RESTRICTED IN THE SOUTHWESTERN SEMICIRCLE...BUT NOT ENOUGH TO
SUGGEST THAT WIND SHEAR IS HAVING ANY EFFECT ON THE CYCLONE YET.
THE LONG-TERM HEADING OVER A 12-HOUR PERIOD IS ABOUT 285-290
DEGREES...BUT THE LAST COUPLE OF AIRCRAFT FIXES AND RECENT GOES
SATELLITE IMAGERY SUGGEST AN INITIAL MOTION THAT IS JUST NORTH OF
DUE WEST AT ABOUT 13 KT. SOME OF THE MODELS...SUCH AS THE GFS AND
HWRF...FORECAST FELICIA TO GAIN A LITTLE MORE LATITUDE BEFORE
TURNING DUE WEST...WHILE MOST OF THE OTHERS CALL FOR THE HURRICANE
TO MOVE AT 270 DEGREES WITHIN THE NEXT FEW HOURS. BEYOND 24 HOURS
OR SO...ALL OF THE GUIDANCE AGREES ON A DUE WESTWARD HEADING ALONG
THE SOUTHERN PERIPHERY OF A LOW- TO MID-LEVEL RIDGE...WITH TRACKS
CROSSING HAWAII AT SLIGHTLY DIFFERENT LATITUDES. THE NEW OFFICIAL
TRACK FORECAST GOES DOWN THE MIDDLE OF THE GUIDANCE ENVELOPE AND
REPRESENTS A SLIGHT NORTHWARD ADJUSTMENT FROM THE PREVIOUS
ADVISORY. SINCE THERE ARE RELIABLE MODELS ON EITHER SIDE OF THE
OFFICIAL FORECAST...THE CENTER OF FELICIA COULD PASS OVER ANY
PORTION OF THE MAIN HAWAIIAN ISLANDS DURING THE NEXT 2-3 DAYS.
FELICIA IS TAKING ITS TIME TO EMBARK UPON A SERIOUS WEAKENING TREND.
THE UNDERLYING SEA-SURFACE TEMPERATURES ARE CURRENTLY ABOUT 25
CELSIUS AND WILL GRADUALLY WARM ALONG THE FORECAST TRACK THROUGHOUT
THE FIVE-DAY FORECAST PERIOD. MEANWHILE...WESTERLY SHEAR IS
FORECAST TO SLOWLY INCREASE AND MAXIMIZE IN ABOUT 48 HOURS...ABOUT
THE TIME FELICIA IS ON THE DOORSTEP OF THE HAWAIIAN ISLANDS. THE
INTENSITY GUIDANCE MODELS RESPOND TO THESE FACTORS BY FORECASTING
GRADUAL WEAKENING...BUT ALL OF THEM HOLD ON TO A TROPICAL STORM
THROUGH 48 HOURS...AND SOME EVEN TO 72 HOURS. THE NEW OFFICIAL
FORECAST IS ADJUSTED SLIGHTLY UPWARD FROM THE PREVIOUS ONE TO BE
CONSISTENT WITH THE INTENSITY CONSENSUS...ICON.
GIVEN THE UNCERTAINTIES WITH INTENSITY FORECASTING...IT IS IMPORTANT
TO POINT OUT THE INTENSITY PROBABILITIES ACCOMPANYING THIS ADVISORY
PACKAGE. THAT PRODUCT INDICATES THAT THERE IS ABOUT A 60 PERCENT
CHANCE OF FELICIA BEING A TROPICAL STORM IN 48 HOURS WHEN IT IS
VERY NEAR THE HAWAIIAN ISLANDS...WITH ABOUT A 25 PERCENT CHANCE OF
IT BEING A TROPICAL DEPRESSION...AND A 10 PERCENT CHANCE OF IT
BEING A HURRICANE.
THE NEW FORECAST NECESSITATES THE ISSUANCE OF A TROPICAL STORM WATCH
FOR PORTIONS OF THE HAWAIIAN ISLANDS...SINCE THE LEAD TIME FOR
WATCHES IN THE CENTRAL PACIFIC BASIN IS 48 HOURS.
FORECAST POSITIONS AND MAX WINDS
INITIAL 09/0300Z 20.1N 143.4W 75 KT
12HR VT 09/1200Z 20.4N 145.4W 65 KT
24HR VT 10/0000Z 20.5N 148.2W 60 KT
36HR VT 10/1200Z 20.5N 151.0W 55 KT
48HR VT 11/0000Z 20.5N 153.7W 45 KT
72HR VT 12/0000Z 20.5N 159.0W 35 KT
96HR VT 13/0000Z 21.0N 164.5W 30 KT
120HR VT 14/0000Z 22.0N 170.0W 30 KT
$$
FORECASTER KNABB/R BALLARD
They are forecasting a stronger system too
lol
dang that looks pretty good for right off africa..
Tropical Storms, Worldwide
I think it is in the southern part of the convection
ohhh felicia. i thought you meant for the cape verde islands i was like WHAT!!!!!
I thought they were in unanimous agreement felicia is going to hit 20kt shear and be a remnant low level swirl by the time it hits. As i said in my blog yesterday evening i'm thinking moderate TS, but i thought i was alone in that thought.
Alright, I appreciate it.
Tropical Cyclone Advisory #22
SEVERE TROPICAL CYCLONE FELICIA (EP082009)
3:00 AM UTC August 9 2009
====================================
SUBJECT: Felicia marching westward.. Tropical Storm Watches Now Issued For Hawaii
At 0:00 AM UTC, Hurricane Felicia (982 hPa) located at 20.1N 143.4W or 660 NM east of of Hilo, Hawaii has sustained winds of 75 knots with gusts of 90 knots. The cyclone is reported as moving west at 13 knots.
Hurricane-force Winds
====================
30 NM from the center
Gale/Storm-force Winds
===============
100 NM from the center
Tropical Cyclone Watches
=======================
A Tropical Storm Watch is now in effect for Big Island of Hawaii.. and all of Maui county, which includes Maui, Kahoolawe, Lanai, and Molokai
Forecast and Intensity
======================
12 HRS: 20.4N 145.4W - 65 knots (SSHS-1 Cyclone)
24 HRS: 20.5N 148.2W - 60 knots (Tropical Storm)
48 HRS: 20.5N 153.7W - 45 knots (Tropical Storm)
72 HRS: 20.5N 159.0W - 35 knots (Tropical Storm)
It's all about the 'U'...
Goodnight everyone. I guess we will see what this does overnight and if it can keep itself together through tomorrow.
Hey dude, I haven't seen you since Ike threatened south Texas. How you been?
Isn't that the same frame?
Correct.
The LLC/MLC is located on the south eastern portion of the convection.
In the past frames from EUMETSAT and RAMMB.
I posted a still. lol
Is there an animation for that floater?
I think you are way too far north on the center. I think it is around 11 to 12N.
Thanks!
Viewing: 1401 - 1451
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