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HURRICANE FRANKLIN
08-09-2017, 11:51 AM (This post was last modified: 08-09-2017 12:38 PM by Her-icane.)
Post: #21
RE: TROPICAL STORM FRANKLIN
[Image: 145554_5day_cone_no_line_and_wind.png]

000
WTNT42 KNHC 091453
TCDAT2

Tropical Storm Franklin Discussion Number 12
NWS National Hurricane Center Miami FL AL072017
1000 AM CDT Wed Aug 09 2017

Franklin continues to become better organized, with increasing
inner-core convection and banding features. The initial intensity
is set at 60 kt based on flight-level and SFMR-observed surface
winds from Air Force and NOAA Hurricane Hunter aircraft.
Observations from the aircraft indicate that the central pressure is
falling, which presages intensification. Radar observations from
the NOAA aircraft indicate that a well-defined eyewall has not yet
developed, however. The tropical cyclone will continue to traverse
SSTs of near 30 deg C until landfall, with northerly shear possibly
impeding strengthening. However, the only evidence of this shear at
this time is a slight restriction of the upper-level outflow over
the northern portion of the circulation. Given the otherwise
favorable atmospheric and oceanic environment, additional
strengthening is forecast up to landfall. The official intensity
forecast is similar to the latest LGEM guidance.

Center fixes from the aircraft give a generally westward motion, or
270/11 kt. A large mid-level high pressure system to the north of
Franklin should maintain the generally westward track until
landfall in eastern Mexico. A slightly more southward motion could
occur while the center crosses the coast, due to interaction with
the topography of Mexico. The official track forecast is close to
the model consensus.

JM


Quote: [Image: franklin-sat-aug9.jpeg]

Franklin Nears Hurricane Strength as it Approaches Mexico
Dr. Jeff Masters · August 9, 2017, 16:16



Above: Tropical Storm Franklin as seen at 12:07 pm EDT August 9, 2017. At the time. Franklin had top winds of 70 mph. Image credit: NASA/GSFC.


Tropical Storm Franklin is steadily intensifying over the hurricane-friendly waters of Mexico’s Bay of Campeche, and is expected to be a Category 1 hurricane with top winds near 85 mph when it makes landfall in the Veracruz state of Mexico, about 70 miles north-northwest of the city of Veracruz, late Wednesday night. Satellite images on Wednesday afternoon showed that Franklin was an averaged-sized tropical storm, with plenty of heavy thunderstorms that filled most of Mexico’s Bay of Campeche. A large rain band was already bringing torrential rains to much of the coast in the warned area. Conditions were favorable for intensification, with sea surface temperatures (SSTs) near 30°C (86°F), plenty of moisture (a mid-level relative humidity near 70%), and moderate wind shear of 15 knots. An Air Force hurricane hunter aircraft penetrated into Franklin's eye at 12:42 pm EDT Wednesday, and found the central pressure was 985 mb--the same as the pressure from NHC's 11 am EDT Wednesday advisory. Radar from a NOAA hurricane hunter aircraft earlier this morning showed that Franklin had not yet built a well-defined eyewall, but the 12:42 pm EDT Wednesday eye report from the Air Force plane reported that Franklin had indeed built a full eyewall, with an elliptical-shaped eye 40 miles long by 20 miles wide.



[Image: franklin-rain-fct.jpg]
Figure 1. Rainfall forecast for Franklin from the RPM model for the period ending 1 pm CDT Thursday (Jueves), August 10, 2017. Image credit: CONAGUA.


Forecast for Franklin


There’s not much time for intensification of Franklin beyond Category 1 status, and the storm is primarily a heavy rainfall threat for Mexico, with widespread rain amounts of 4 – 8” expected. Franklin should have a lower impact than the last hurricane to hit the state of Veracruz, Hurricane Karl, whose eye crossed the coast about 10 miles north of Veracruz on September 17, 2010. Karl was the only major hurricane ever recorded in the Bay of Campeche (south of 21° N latitude), and peaked as a Category 3 storm with 125 mph winds, about 5 hours before landfall. Karl brought a large area of 10 – 15” rainfall amounts to the northwestern half of the state of Veracruz. AIR Worldwide estimated total damage costs in Mexico at $206 million, and Karl killed 22 people. Karl did not get its name retired.





Invest 99L not a threat to land areas


An area of low pressure (99L) located about 400 miles east of the northern Lesser Antilles Islands at 8 am EDT Wednesday was headed west-northwest to northwest at about 10 mph. Satellite images on Wednesday afternoon showed that 99L had only a sparse amount of heavy thunderstorm activity, but a modest degree of spin. The atmosphere surrounding the disturbance was quite dry, with a mid-level relative humidity around 45%.


The 12Z Wednesday run of the SHIPS modelpredicted that wind shear would drop to the low range, less than 10 knots, on Friday and Saturday, when 99L was expected to be a few hundred miles north of the Lesser Antilles Islands. However, the atmosphere was predicted be very dry at that time, potentially limiting development--unless 99L can carve out a protective “pouch” of moisture to stave off the dryness.


By Sunday, 99L should find a moister atmosphere with mid-level relative humidity around 60%, though wind shear is predicted to rise to a moderately high 15 – 20 knots by then. Sea surface temperatures will be plenty warm enough for development, around 29°C (84°F)--about 1°C above average for this time of year. The 0Z Wednesday European model ensemble forecast had 46% of its members bringing 99L between North Carolina and Bermuda as a tropical storm early next week. However, our other two reliable models for predicting tropical cyclone genesis, the GFS and UKMET models, did not show development of 99L in their 0Z Wednesday runs. The 12Z Wednesday run of the GFS also showed no development, though the 12Z Wednesday run of the UKMET did show some weak development early next week.


If it does manage to develop, 99L will be steered by a large and strong Atlantic ridge extending west toward the mid-Atlantic coast. The predicted shape of the ridge, and the projected approach of a strong upper-level trough across the Northeast U.S., suggests that 99L will recurve to the north and north-northeast between North Carolina and Bermuda, sparing those locations any direct impacts. In its 8 am Wednesday tropical weather outlook, the NOAA/NWS National Hurricane Center gave 99L a near-zero chance of developing into at least a tropical depression by Friday morning, but a 40% chance by Monday morning.
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08-09-2017, 04:14 PM
Post: #22
RE: HURRICANE FRANKLIN
000
WTNT42 KNHC 092041
TCDAT2

Hurricane Franklin Discussion Number 13
NWS National Hurricane Center Miami FL AL072017
400 PM CDT Wed Aug 09 2017

Hurricane Hunter aircraft observations from earlier today indicated
that Franklin was very close to hurricane strength. Since the time
of the last mission, the system has become better organized, with a
faint eye occasionally making an appearance on visible satellite
images. Dvorak intensity estimates from both TAFB and SAB are 65
kt and this value will be used for the advisory intensity, making
Franklin the first hurricane of the season. There is some northerly
shear evident over the system and with several arc clouds evident
over the outer circulation's northwest quadrant, perhaps some dry
air is nearby. These environmental conditions are not expected to
be detrimental enough, however, to prevent at least some additional
strengthening before landfall tonight. An Air Force Hurricane
Hunter aircraft is scheduled to investigate Franklin a few hours
from now to check the strength of the cyclone.

The hurricane continues to move westward, with the initial motion
estimated to be 270/10. There are essentially no changes to the
track forecast or reasoning. The flow on the southern side of a
mid-level high pressure area near the Texas coast should continue
to steer Franklin towards, and across, the southwest Gulf coast of
Mexico. The official track forecast follows the latest dynamical
track model consensus.
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08-09-2017, 04:43 PM
Post: #23
RE: HURRICANE FRANKLIN
First cane of 2017 ! That took long enough

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08-09-2017, 05:31 PM
Post: #24
RE: HURRICANE FRANKLIN
(08-09-2017 04:43 PM)ROLLTIDE Wrote:  First cane of 2017 ! That took long enough
And too bad it's much ado about nothing - I'm sure the folks in Veracruz would beg to differ as they get drenched, but it just isn't going to be much more than a heavy t-storm for most......let's all keep good thoughts for those who will be affected regardless.....
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08-09-2017, 08:08 PM (This post was last modified: 08-09-2017 08:29 PM by Her-icane.)
Post: #25
RE: HURRICANE FRANKLIN
000
WTNT32 KNHC 092346
TCPAT2

BULLETIN
Hurricane Franklin Intermediate Advisory Number 13A
NWS National Hurricane Center Miami FL AL072017
700 PM CDT Wed Aug 09 2017

...STRENGTHENING HURRICANE FRANKLIN HEADING FOR THE COAST OF
MEXICO...
...WEATHER SHOULD BEGIN TO DETERIORATE SOON...


SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...20.2N 95.4W
ABOUT 135 MI...220 KM ESE OF TUXPAN MEXICO
ABOUT 90 MI...140 KM NE OF VERACRUZ MEXICO
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...983 MB...29.03 INCHES



Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 10th day of the month at 0:16Z
Agency: United States Air Force
Aircraft: Lockheed WC-130J Hercules with reg. number AF98-5308
Storm Number & Year: 07 in 2017
Storm Name: Franklin (flight in the North Atlantic basin)
Mission Number: 6
Observation Number: 05
A. Time of Center Fix: 9th day of the month at 23:38:50Z
B. Center Fix Coordinates: 20°19'N 95°23'W (20.3167N 95.3833W)
B. Center Fix Location: 211 statute miles (340 km) to the SE (130°) from Tampico, Tamaulipas, Mexico.
C. Minimum Height at Standard Level: 1,274m (4,180ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind Inbound: 78kts (~ 89.8mph)
E. Location of the Estimated Maximum Surface Wind Inbound: 13 nautical miles (15 statute miles) to the NE (41°) of center fix
F. Maximum Flight Level Wind Inbound: From 150° at 89kts (From the SSE at ~ 102.4mph)
G. Location of Maximum Flight Level Wind Inbound: 21 nautical miles (24 statute miles) to the NE (45°) of center fix
H. Minimum Sea Level Pressure: 981mb (28.97 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 15°C (59°F) at a pressure alt. of 1,512m (4,961ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 23°C (73°F) at a pressure alt. of 1,528m (5,013ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 13°C (55°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind and Pressure
N. Fix Level: 850mb
O. Navigational Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 5 nautical miles

Remarks Section:
Maximum Flight Level Wind: 89kts (~ 102.4mph) which was observed 23 nautical miles (26 statute miles) to the NE (42°) from the flight level center at 23:31:30Z
Dropsonde Surface Wind at Center: From 245° at 7kts (From the WSW at 8mph)
Maximum Flight Level Temp: 23°C (73°F) which was observed 6 nautical miles to the NNE (24°) from the flight level center
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08-09-2017, 10:12 PM
Post: #26
RE: HURRICANE FRANKLIN
000
WTNT32 KNHC 100245
TCPAT2

BULLETIN
Hurricane Franklin Advisory Number 14
NWS National Hurricane Center Miami FL AL072017
1000 PM CDT Wed Aug 09 2017

...HURRICANE FRANKLIN EXPECTED TO MAKE LANDFALL IN THE NEXT
SEVERAL HOURS ACCOMPANIED BY TORRENTIAL RAINS
...


SUMMARY OF 1000 PM CDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...20.2N 96.1W
ABOUT 100 MI...160 KM ESE OF TUXPAN MEXICO
ABOUT 70 MI...110 KM N OF VERACRUZ MEXICO
MAXIMUM SUSTAINED WINDS...85 MPH...140 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...985 MB...29.09 INCHES
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08-10-2017, 06:24 PM
Post: #27
RE: HURRICANE FRANKLIN
JM


Quote: [Image: franklin-boat.jpg] Hurricane Franklin

Dissipates Over Mexico; 99L May Develop

Dr. Jeff Masters · August 10, 2017, 16:05


Above: Fishermen push a boat out of the sea in anticipation of the arrival of Tropical Storm Franklin in the port city of Veracruz in Veracruz state, Mexico on August 9, 2017. Image credit: VICTORIA RAZO/AFP/Getty Images.
Hurricane Franklin dissipated over the rugged terrain of central Mexico east of Mexico City on Thursday morning, after making landfall at 1 am EDT Thursday, August 10, in the Veracruz state of Mexico, about 70 miles north of the city of Veracruz. Franklin became the first Atlantic hurricane of 2017 at 5 pm EDT August 9. This formation date is just one day earlier than the average August 10 formation date of the season’s first hurricane. At landfall, Franklin was at peak intensity--a Category 1 hurricane with 85 mph winds.



[Image: franklin-modis-aug9.jpeg]Figure 1. MODIS true-color satellite image of Franklin, taken at 2:54 pm EDT August 9, 2017. At the time, Franklin was a tropical storm with 70 mph sustained winds, and would be upgraded to a hurricane two hours later. Image credit: NASA.

Impact of Franklin

Franklin should end up dumping widespread rain amounts of 4 – 8” along its track, resulting in a less severe impact than the last hurricane to hit the state of Veracruz, Hurricane Karl. Karl crossed the coast about 10 miles north of Veracruz on September 17, 2010, bringing a large area of 10 – 15” rainfall amounts to the northwestern half of the state of Veracruz. Karl was the only major hurricane ever recorded in the Bay of Campeche (south of 21° N latitude), and peaked as a Category 3 storm with 125 mph winds, about 5 hours before landfall. AIR Worldwide estimated total damage costs in Mexico at $206 million, and Karl killed 22 people. Karl did not get its name retired.



Franklin’s remains could regenerate over the Pacific

Satellite images on Thursday morning showed that the remains of Franklin were bringing heavy rains to much of south-central Mexico, and were headed westwards at 20 mph. Franklin’s remains will emerge over the Pacific Ocean on Friday, when regeneration into a tropical depression may occur, as predicted by both the 0Z and 6Z Thursday runs of the GFS model. The European model was more ambivalent about regeneration, but did show some reorganization would occur this weekend. In their 8 am Thursday tropical weather outlook, the National Hurricane Center gave the remains of Franklin a 20% chance of redeveloping over the Pacific by Saturday morning, and a 40% chance by Tuesday morning. The storm is expected to move west-northwest, passing several hundred miles south of the southern tip of Mexico’s Baja Peninsula early next week. Since Franklin did not survive the crossing of Mexico as an identifiable tropical cyclone, the new storm would get a new Eastern Pacific name. The next named storm in the list is Jova. By early next week, any potential Tropical Storm Jova will encounter a less conducive atmosphere for development, and it is unlikely that we will see a Hurricane Jova.


As documented by The Weather Company’s Jon Erdman in his Thursday morning post, a similar scenario happened almost exactly one year ago, also resulting in an eastern Pacific "J" storm. Hurricane Earl made landfall in Belize on Aug. 4, 2016, and less than 24 hours after Earl dissipated, a tropical depression formed from the remnants of Earl. This storm went on to develop into Tropical Storm Javier. Since the mid-1960s, when satellite surveillance of the tropics became routine, the remnants of tropical cyclones crossing from one ocean basin to the other and reforming has occurred every 3 to 4 years.



[Image: viz-99L-1530Z-8.10.17.jpg]
Figure 2. Visible-wavelength GOES-16 satellite image of Invest 99L as of 1530Z (11:30 am EDT) Thursday, August 20, 2017. GOES-16 images are preliminary and non-operational. Image credit: RAMMB/CIRA/CSU.

99L may yet develop this weekend

It’s been a fighter, but the never-say-die tropical wave known as Invest 99L continues to face long odds. The resilient system may have its last, best shot at development this weekend, though. Located several hundred miles northeast of the Virgin islands on Thursday morning, 99L maintained a small core of showers and thunderstorms (convection) through Wednesday night. The convection was not intense or very well structured, and it was mostly east of the ill-defined center of 99L, but it was expanding in area on Thursday morning. Relentless wind shear—on the order of 20-25 knots on Thursday morning—is projected in the 12Z Thursday SHIPS model output to decrease to a more moderate 10-15 knots on Friday and Saturday, before again increasing on Sunday and Monday to around 20 knots. Mid-level relative humidity around 99L is also projected to increase, to around 50-55% this weekend, and sea surface temperatures of around 29°C will be more than adequate for development. In its 8 AM Thursday tropical weather outlook, NHC gave 99L a 20% chance of development into at least a depression by Saturday and a 40% chance by Tuesday.


The European model has pulled back on its bullish outlook for 99L after most of its ensemble members a day before had developed the system into a tropical storm or hurricane. About 2/3 of the 00Z Thursday Euro ensemble members create a tropical depression out of 99L by Friday evening. However, less than 10% bring the system to tropical storm strength, and only one of the 50 members creates a long-track tropical storm that recurves off the East Coast. None of the GFS ensemble members from 00Z Thursday develops 99L at all, and the same is true in the 00Z Thursday operational runs from our three top global models for tropical cyclone development: the Euro, GFS, and UKMET.



Elsewhere in the tropics

A new wave coming off Africa early next week will bear watching as we approach the peak of the Cape Verde season, when the Main Development Region (MDR) between Africa and the Lesser Antilles is at its most active. About 30% of Euro and 20% of GFS ensemble members bring this wave to at least tropical depression strength next week, as it heads west-northwest across the MDR on a track that could end up similar to 99L’s.


The Madden-Julian Oscillation should be in a mode that favors development in the Atlantic during mid- to late August, based on the latest NOAA forecasts of rising and sinking air at upper levels.


In the Eastern Pacific, there is the chance that the remnants of Franklin will redevelop (as discussed above), and another tropical low is expected to take shape early next week further to the south. NHC gave that system a 40% chance of development through Tuesday in its Thursday morning outlook.
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