Tropical Storm Elsa A Long-Range Threat To The Region
000
WTNT35 KNHC 040249
TCPAT5
BULLETIN
Tropical Storm Elsa Advisory Number 15
NWS National Hurricane Center Miami FL AL052021
1100 PM EDT Sat Jul 03 2021
...RECONNAISSANCE AIRCRAFT FINDS ELSA A LITTLE WEAKER AND MOVING
SLOWER BETWEEN HAITI AND JAMAICA...
SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...17.9N 75.3W
ABOUT 175 MI...280 KM ESE OF MONTEGO BAY JAMAICA
ABOUT 205 MI...330 KM SE OF CABO CRUZ
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...1004 MB...29.65 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
The Hurricane Warning for the southern portion of Haiti from Port
Au Prince to the southern border with the Dominican Republic has
been replaced with a Tropical Storm Warning.
The Tropical Storm Warning for Haiti north of Port Au Prince has
been discontinued.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Warning is in effect for...
* Southern portion of Haiti from Port Au Prince to the southern
border with the Dominican Republic
* The Cuban provinces of Camaguey, Granma, Guantanamo, Holguin,
Las Tunas, Santiago de Cuba, Ciego de Avila, Sancti Spiritus, Villa
Clara, and Cienfuegos
* Jamaica
A Hurricane Watch is in effect for...
* The Cuban provinces of Camaguey, Granma, Guantanamo, Holguin,
Las Tunas, and Santiago de Cuba
A Tropical Storm Watch is in effect for...
* Cayman Brac and Little Cayman
* The Cuban provinces of Matanzas, Mayabeque, and Havana
* The Florida Keys from Craig Key westward to the Dry Tortugas
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.
A Hurricane Watch means that hurricane conditions are possible
within the watch area. A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area.
Interests elsewhere in the Cuba, the Cayman Islands, the Florida
peninsula, and the Florida Keys should monitor the progress of Elsa.
Additional watches and warnings will likely be required Sunday
morning.
For storm information specific to your area in the United States,
including possible inland watches and warnings, please monitor
products issued by your local National Weather Service forecast
office. For storm information specific to your area outside of the
United States, please monitor products issued by your national
meteorological service.
DISCUSSION AND OUTLOOK
----------------------
At 1100 PM EDT (0300 UTC), the center of Tropical Storm Elsa was
located by an Air Force Reserve reconnaissance aircraft near
latitude 17.9 North, longitude 75.3 West. Elsa is moving toward the
west-northwest near 17 mph (28 km/h). An additional decrease in
forward speed is expected tonight and on Sunday, followed by a turn
toward the northwest Sunday night or Monday. On the forecast track,
Elsa will move near the southwestern peninsula of Haiti over the
next few hours, and then move near Jamaica and portions of eastern
Cuba on Sunday. By Monday, Elsa is expected to move across central
and western Cuba and head toward the Florida Straits. Elsa is then
forecast to move move near or over portions of the west coast of
Florida on Tuesday.
Maximum sustained winds have decreased to near 65 mph (100 km/h)
with higher gusts. Little change in strength is forecast tonight,
with some slight strengthening possible Sunday afternoon as Elsa
approaches the south-central coast of Cuba. However, gradual
weakening is forecast to occur Sunday night and Monday when Elsa
will be moving over Cuba.
Tropical-storm-force winds extend outward up to 125 miles (205 km)
from the center.
The minimum central pressure recently measured by the aircraft was
estimated to be 1004 mb (29.65 inches).
HAZARDS AFFECTING LAND
----------------------
Key messages for Elsa can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT5, WMO header WTNT45 KNHC and
on the web at
www.hurricanes.gov/graphics_at5.shtml?key_messages.
WIND: Hurricane conditions are possible in eastern Cuba on Sunday.
Tropical Storm conditions are expected in the warning area in Haiti
tonight and on Jamaica and over eastern and central Cuba on Sunday.
Tropical storm conditions are possible in the watch area in the
Cayman Islands Sunday and Sunday night and in western Cuba and the
Florida Keys Sunday night and Monday.
STORM SURGE: A storm surge will raise water levels above normal
tide levels by as much as the following amounts in areas of onshore
flow within the hurricane watch and warning areas...
Southern coast of Cuba...3 to 5 feet
Southern coast of Hispaniola...2 to 4 feet
The combination of a storm surge and the tide will cause normally
dry areas near the coast to be flooded by rising waters moving
inland from the shoreline. The water could reach the following
heights above ground somewhere in the indicated areas if the peak
surge occurs at the time of high tide...
Craig Key, FL to Dry Tortugas...1-2 ft
Surge-related flooding depends on the relative timing of the surge
and the tidal cycle, and can vary greatly over short distances. For
information specific to your area, please see products issued by
your local National Weather Service forecast office.
RAINFALL: Across portions of southern Haiti and Jamaica, rainfall
of 4 to 8 inches with isolated maximum amounts of 15 inches is
expected today into Sunday. This rain may lead to scattered flash
flooding and mudslides, some of which may be significant in nature.
Across portions of Cuba Sunday into Monday, rainfall of 5 to 10
inches with isolated maximum amounts of 15 inches is expected. This
will result in significant flash flooding and mudslides.
Across the Cayman Islands Sunday into Monday, rainfall of 3 to 5
inches is expected. This rain may lead to scattered flash flooding.
Rainfall from Elsa is likely to impact portions of the Florida Keys
and Florida Peninsula early next week. Amounts of 2 to 4 inches with
localized maximum amounts up to 6 inches will be possible, which may
result in isolated flash, urban, and minor river flooding.
SURF: Swells generated by Elsa will spread westward across the
Caribbean Sea through the weekend. These swells are likely to cause
life-threatening surf and rip current conditions. Please consult
products from your local weather office.
NEXT ADVISORY
-------------
Next intermediate advisory at 200 AM EDT.
Next complete advisory at 500 AM EDT.
$$
Forecaster Stewart/Papin
454
WTNT45 KNHC 040259
TCDAT5
Tropical Storm Elsa Discussion Number 15
NWS National Hurricane Center Miami FL AL052021
1100 PM EDT Sat Jul 03 2021
Elsa is undergoing a convective bursting pattern the past few
hours, with some cold overshooting tops of -90 deg C east and
northeast of the center. However, data from an Air Force Reserve
reconnaissance aircraft indicate that this convective increase has
not translated into an intensity increase. To the contrary, 5000-ft
flight-level and SFMR surface winds have decreased while the central
pressure has increased to 1004 mb. Based on the latest recon data,
the intensity has been lowered to 55 kt. The aircraft has now
climbed to 10,000 ft for safety reasons and will be penetrating the
area of intense convection to check for stronger winds there.
The initial motion estimate is now 295/15 kt. Elsa is forecast to
gradually move around the western periphery of a deep-layer
subtropical ridge over the next 96 hours, accompanied by an
additional decrease in forward speed. The latest model guidance has
continued to converge along the previous advisory track, with the
corrected-consensus models HCCA and FSSE nearly on top of each
other. The TCVA simple consensus model is also similar to the HCCA
and FSSE models. However, out of respect for the slightly more
westward GFS and GFS-ensemble models, which have performed
admirably thus far with Elsa, the new official forecast lies a tad
west of the aforementioned consensus models and lies nearly on top
of the previous advisory track.
After interacting with the mountainous terrain of southwestern
Haiti, which could have caused some disruption in the low-level
field despite the center remaining offshore, little change in
intensity is expected tonight. However, some slight restrengthening
could occur by Sunday afternoon as Elsa approaches the south-central
coast of Cuba where the sea-surface temperatures are quite warm at
more than 30 deg C and the water is deep. Weakening is expected
after the cyclone moves across west-central Cuba, followed again by
some slight restrengthening after Elsa emerges over the warm Gulf
Stream in the Straits of Florida. Westerly vertical wind shear
increasing to near 20 kt by 96 hours should prevent any significant
strengthening from occurring. Elsa should become a very
asymmetrical tropical cyclone late on day 3 and on day 4 with most
of the heavy rain and strongest winds displaced along and to the
east of the forecast track. The initial intensity is similar to the
previous advisory and closely follows the simple and corrected
consensus models.
Given the remaining uncertainty in the track forecast and the degree
of land interaction with Hispaniola and Cuba, users are urged to
factor in some of this uncertainty. For reference, average NHC
track errors at days 3 and 4 are 125 miles and 150 miles,
respectively. The average NHC intensity errors are around 15 mph
for both days 3 and 4.
Key Messages:
1. Widespread heavy rain will move across southern Haiti and Jamaica
tonight into Sunday where isolated to scattered flash flooding and
mudslides will be possible. Heavy rain will then impact the Cayman
Islands and Cuba Sunday into Monday resulting in significant
flooding and mudslides over Cuba. As Elsa approaches the Florida
Keys and Florida Peninsula early next week, isolated flash flooding
and minor river flooding will be possible.
2. Tropical storm conditions and dangerous storm surge are expected
with hurricane conditions possible in portions of eastern Cuba
beginning early Sunday, with tropical storm conditions possible in
central and western Cuba Sunday night and Monday.
3. There is an increasing risk of tropical storm conditions, storm
surge, and rainfall impacts beginning Monday in the Florida Keys and
the southern Florida Peninsula, and a Tropical Storm Watch is now
in effect for portions of the Florida Keys. This risk will spread
northward along the Florida Peninsula through Wednesday and reach
the coasts of Georgia and the Carolinas Wednesday and Thursday,
however uncertainty in the forecast remains larger than usual due
to Elsa's potential interaction with the islands of Hispaniola and
Cuba. Interests elsewhere in Florida and along the southeast U.S.
coast should monitor Elsa's progress and updates to the forecast.
FORECAST POSITIONS AND MAX WINDS
INIT 04/0300Z 17.9N 75.3W 55 KT 65 MPH
12H 04/1200Z 19.2N 77.3W 55 KT 65 MPH
24H 05/0000Z 20.9N 79.4W 60 KT 70 MPH
36H 05/1200Z 22.5N 81.0W 50 KT 60 MPH...INLAND
48H 06/0000Z 24.1N 82.2W 45 KT 50 MPH...OVER WATER
60H 06/1200Z 26.0N 82.8W 50 KT 60 MPH
72H 07/0000Z 28.0N 83.0W 50 KT 60 MPH
96H 08/0000Z 32.7N 81.0W 45 KT 50 MPH...INLAND
120H 09/0000Z 37.7N 74.9W 35 KT 40 MPH...OVER WATER
$$
Forecaster Stewart/Papin
posted by Advackia at 8:14 PM
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