1 Aug Weather in Cayman & Tropical Report, TD Emily

August 1, 2017

Aug 1 Tuesday 2017

Tropical Report

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Tue Aug 1 2017

For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Tropical
Depression Emily, located over the Atlantic Ocean just east of
Cape Canaveral, Florida.

Tropical cyclone formation is not expected during the next 5 days.

Public Advisories on Tropical Depression Emily are issued under WMO
header WTNT31 KNHC and under AWIPS header MIATCPAT1.
Forecast/Advisories on Tropical Depression Emily are issued under
WMO header WTNT21 KNHC and under AWIPS header MIATCMAT1.

$$
Forecaster Stewart

POORLY ORGANIZED EMILY MOVES OVER THE WESTERN ATLANTIC

Tropical Depression Emily Discussion Number 6
NWS National Hurricane Center Miami FL AL062017
500 AM EDT Tue Aug 01 2017

Radar and surface observations over east-central Florida indicate
that Emily’s circulation has become quite elongated. Water vapor
imagery also shows that drier mid-level air has moved over the
northwestern portion of the circulation, which has limited the
amount of convection near the center overnight. Some deep
convection is noted along a trough axis well to the northeast of
Emily. Earlier ASCAT data revealed a few 20-25 kt wind vectors just
off the coast of Florida to the southeast of the center, so the
initial intensity remains 25 kt for this advisory.

Emily has been moving east-northeastward overnight. The cyclone
remains embedded within the base of a mid-level trough that extends
southwestward just off the southeastern United States coast. As
this trough lifts out, Emily should accelerate northeastward between
the western Atlantic ridge and another mid-level trough that will
approach the southeast United States in a day or so. The global
models shifted slightly westward this cycle, and the new NHC
track has been nudged in that direction.

The intensity forecast remains quite uncertain. Since Emily’s
circulation has become less defined and is near a weak frontal
zone, it is possible that that system will be absorbed within the
larger trough axis. For now, the NHC forecast assumes that Emily
will maintain its identity and have a chance to restrengthen over
the western Atlantic. Although the shear is not forecast to be
prohibitive during the next day or so, the current structure and
nearby dry air suggest any deepening should be slow to occur. This
is supported by the global models which do not indicate much
intensification. The NHC forecast is a little below the previous
advisory and is close to guidance provided by the NOAA Ocean
Prediction Center. Emily is forecast to become extratropical in
about 36 hours, but it could dissipate or become post-tropical
sooner than that.

FORECAST POSITIONS AND MAX WINDS

INIT 01/0900Z 28.3N 80.1W 25 KT 30 MPH
12H 01/1800Z 29.4N 78.6W 25 KT 30 MPH
24H 02/0600Z 31.0N 76.5W 30 KT 35 MPH
36H 02/1800Z 32.8N 73.6W 30 KT 35 MPH…POST-TROP/EXTRATROP
48H 03/0600Z 34.4N 70.4W 30 KT 35 MPH…POST-TROP/EXTRATROP
72H 04/0600Z 37.0N 64.0W 30 KT 35 MPH…POST-TROP/EXTRATROP
96H 05/0600Z 38.5N 57.0W 30 KT 35 MPH…POST-TROP/EXTRATROP
120H 06/0600Z…DISSIPATED

$$
Forecaster Brown

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Tue Aug 1 2017

For the eastern North Pacific…east of 140 degrees west longitude:

The National Hurricane Center is issuing advisories on Tropical
Storm Irwin, located more than a thousand miles west of the southern
tip of the Baja California peninsula.

1. An area of disturbed weather located several hundred miles
south-southeast of the Gulf of Tehuantepec is associated with a
tropical wave. Environmental conditions appear conducive for some
slow development of this disturbance during the next several days
while it moves west-northwestward at 10 to 15 mph south of the coast
of Mexico.
* Formation chance through 48 hours…low…20 percent.
* Formation chance through 5 days…medium…40 percent.

Forecaster Avila

Tropical Storm Irwin Discussion Number 40
NWS National Hurricane Center Miami FL EP102017
200 AM PDT Tue Aug 01 2017

Irwin stubbornly remains a tropical cyclone this morning. The
systems continues to produce a small area of deep convection near
the center despite being over SSTs of around 22 deg C. The
convection has gradually waned over the past 24 hours, but recent
ASCAT data indicate that the maximum winds remain around 40 kt.
Irwin should lose all of its remaining convection later today, and
should become post-tropical within the next 12 to 24 hours while it
moves over even colder waters. As a result, the system is forecast
to gradually spin down, with the remnant circulation dissipating in
2 to 3 days.

A mid-level high pressure area to the northeast of Irwin continues
to steer the cyclone north-northwestward. This general motion is
forecast to continue this morning. As Irwin weakens and becomes a
shallow system, it should slow down and turn northwestward. The
track guidance remains in agreement on this scenario and no
significant change to the previous forecast was required.

FORECAST POSITIONS AND MAX WINDS

INIT 01/0900Z 24.9N 128.8W 40 KT 45 MPH
12H 01/1800Z 26.2N 129.7W 30 KT 35 MPH
24H 02/0600Z 27.5N 130.8W 25 KT 30 MPH…POST-TROP/REMNT LOW
36H 02/1800Z 28.4N 131.7W 20 KT 25 MPH…POST-TROP/REMNT LOW
48H 03/0600Z 29.2N 132.6W 15 KT 15 MPH…POST-TROP/REMNT LOW
72H 04/0600Z…DISSIPATED

$$
Forecaster Brown

Weather In Cayman

Synopsis

Isolated showers along with light southeasterly winds and slight seas are expected to continue across the Cayman Islands for the next 24 hours in association with a slack pressure gradient across the northwest Caribbean. Further east, tropical wave over Jamaica is expected to move into the Cayman area tomorrow morning with little change in the weather conditions. Radar images show isolated showers in and around the Cayman area which are moving towards the west. At 7 a.m. the National Hurricane Center in Miami Florida continues to issue advisories on Tropical Depression Emily which is located about 50 miles north northeast of Vero Beach Florida. For further information on this Depression, please visit www.nhc.noaa.gov. THIS DEPRESSION POSES NO THREAT TO THE CAYMAN ISLANDS.

Sunshine just makes the day a little better, but it can also cause sunburns. Check the UV Report below to be prepared

Humidity: 81% (DOWN from yesterday)

UV: 12.4 EXTREME (UP from yesterday)

Temperature: Today’s current temperature – See Weather Forecast Top Right of Website. Yesterday: H 92.7°F L 82.8°F

Wind direction TODAY: ESE 10-20 mph GC

Wind direction TONIGHT: E 10-15 mph GC

Barometer: 1016:00 mb Steady Rain: Last month: 6.69 in Last 24 hrs 0.00 This month: 0.00 in

12 Rain days in July 0 Rain days in Aug 4 days since rain

2016 Season Total: 20.23 in 2017 Season Total: 19.36 in

*NOTE: Official Government record of rainfall on Grand Cayman (Owen Roberts International Airport) 2016: 27.98 inches or 28.22 inches below the 30 year average rainfall of 56.20 inches. All other readings are from SOUTH SOUND.