22 Sep Weather in Cayman & Tropical Report, 1 TD 3 Dist
22 Sep Sat 2018
Tropical Report
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Sat Sep 22 2018
For the North Atlantic…Caribbean Sea and the Gulf of Mexico:
The National Hurricane Center is issuing advisories on Tropical
Depression Eleven, located about 500 miles east of the Windward
Islands.
1. Shower and thunderstorm activity continues to become better
organized near the center of a low pressure system located about
500 miles south of the southern Cabo Verde Islands, and a tropical
depression appears to be forming. If these trends continue,
advisories will be initiated on this system later today while the
low moves westward at about 20 mph.
* Formation chance through 48 hours…high…80 percent.
* Formation chance through 5 days…high…80 percent.
2. A broad area of low pressure located about 200 miles south of
Bermuda is producing only minimal shower activity. Strong upper-
level winds are expected to diminish by Sunday or Monday, which
could allow for some slow development of this system while it moves
westward and then northwestward over the southwestern Atlantic
Ocean. By the middle of next week, upper-level winds are likely to
strengthen again, which would limit additional development as the
system moves closer to the southeastern coast of the United States.
* Formation chance through 48 hours…low…10 percent.
* Formation chance through 5 days…low…30 percent.
3. Satellite imagery indicates that a non-tropical low pressure system
is forming along a frontal boundary about 900 miles west-southwest
of the Azores. Conditions are expected to become conducive for the
low to acquire subtropical or tropical characteristics, and a
subtropical or tropical cyclone is likely to form by early next week
while the low meanders over the central Atlantic Ocean. For more
information on this system, see High Seas Forecasts issued by the
National Weather Service.
* Formation chance through 48 hours…medium…60 percent.
* Formation chance through 5 days…high…70 percent.
Public Advisories on Tropical Depression Eleven are issued under WMO
header WTNT31 KNHC and under AWIPS header MIATCPAT1.
Forecast/Advisories on Tropical Depression Eleven are issued under
WMO header WTNT21 KNHC and under AWIPS header MIATCMAT1.
High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
on the Web at https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.
Forecaster Brennan
TROPICAL DEPRESSION NOT MOVING VERY MUCH… …EXPECTED TO DISSIPATE IN A DAY OR TWO
Tropical Depression Eleven Discussion Number 2
NWS National Hurricane Center Miami FL AL112018
500 AM AST Sat Sep 22 2018
Deep convection remains displaced to the east of the depression’s
center due to 30-40 kt of westerly shear. Although Dvorak final-T
numbers from TAFB and SAB have decreased since yesterday–now a
consensus T1.0–the initial intensity is held, perhaps generously,
at 30 kt. Strong westerly shear is expected to persist for several
days, which at the very least will prevent the depression from
getting any better organized. Since the global models show the
depression opening up into a trough in about 24 hours, the new NHC
intensity forecast brings down the winds a little faster, shows the
system becoming a remnant low by 36 hours, and dissipates the low
entirely by 48 hours well east of the Windward Islands. This
evolution could certainly occur more quickly than indicated by the
official forecast.
The center of the depression has not been moving much, and it’s
possible the sheared convection is trying to pull it back toward
the east. However, the average motion over the past 12 hours is
westward, or 270/4 kt. The track guidance insists that the
depression should move slowly west-northwestward over the next
couple of days, but given that the system has not made any
northward progress, I elected to skirt the southern edge of the
guidance envelope. This new forecast is a little south of the
previous NHC track prediction.
FORECAST POSITIONS AND MAX WINDS
INIT 22/0900Z 13.0N 53.5W 30 KT 35 MPH
12H 22/1800Z 13.3N 54.3W 30 KT 35 MPH
24H 23/0600Z 13.6N 55.4W 25 KT 30 MPH
36H 23/1800Z 13.8N 56.8W 25 KT 30 MPH…POST-TROP/REMNT LOW
48H 24/0600Z…DISSIPATED
$$
Forecaster Berg
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sat Sep 22 2018
For the eastern North Pacific…east of 140 degrees west longitude:
1. An area of low pressure is expected to form in a couple of days well
south of the southern coast of Mexico. Environmental conditions are
expected to be conducive for gradual development, and a tropical
depression could form by the middle of next week well south of the
southwestern coast of Mexico.
* Formation chance through 48 hours…low…near 0 percent.
* Formation chance through 5 days…medium…60 percent.
Forecaster Brennan
Global Tropics & Benefits Outlook
Weather in Cayman
SYNOPSIS
Isolated showers are expected over the Cayman area today as a tropical wave interacts with an upper level trough over the northwestern Caribbean. Radar images show scattered showers around the Cayman area moving towards the west.
Humidity: 85% (UP from yesterday)
UV: 12.6 EXTREME (UP from yesterday)
Temperature: Today’s current temperature – See weather forecast top right of website. Yesterday: H 91.9°F L 77.5°F
Wind direction TODAY: E 10-20 mph GC
Wind direction TONIGHT: ENE 5-10 mph GC
Barometer: 1014.20 mb Rising slowly Rain: Last month: 1.83 in Last 24 hrs 0.09 This month: 12.21 in 0 days since rain 12 rain days in September
2017 Season Total: 62.94 in 2018 Season Total: 36.22 in
Average Yearly Rainfall 56.20 in (Note: National Weather Service 2017 Season Total – measured at Owen Roberts Airport GT – was 59.32 in)
All readings are from SOUTH SOUND.
Average rainfall in September 8.2 in. Average temperature in September: 77°F to 90°F
Sea Temperature in September 84°F
MOON:
94% Waxing Gibbous
TIDES, SUNRISE, SUNSET, MOON RISE, MOON SET AND MOON PHASE
GRAND CAYMAN SEPTEMBER 2018 – Click to enlarge
LOCAL 5 DAY FORECAST
http://www.weather.gov.ky/portal/page?_pageid=4421,7428393&_dad=portal&_schema=PORTAL
FOR RADAR IMAGE GO TO: http://www.weather.gov.ky/portal/page/portal/nwshome/forecasthome/radar
Also see Weather In Cayman: http://www.weatherincayman.com/
Moon info and graphic:
https://www.timeanddate.com/moon/uk/georgetown
Atlantic satellite image: http://www.intellicast.com/global/satellite/infrared.aspx?region=hiatlsat
Description:
The Global Infrared Satellite image shows clouds by their temperature. Red and blue areas indicate cold (high) cloud tops. Infrared (IR) radiation is electromagnetic radiation whose wavelength is longer than that of visible light, but shorter than that of terahertz radiation and microwaves. Weather satellites equipped with scanning radiometers produce thermal or infrared images which can then enable a trained analyst to determine cloud heights and types, to calculate land and surface water temperatures, and to locate ocean surface features.
Tropical storm data and graphics from National Hurricane Center at: https://www.nhc.noaa.gov/
Weathernerds: https://www.weathernerds.org/
Mikes Weather Page: http://www.spaghettimodels.com/
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