13 Sep Weather in Cayman & Tropical Report, 1 H-cane
Sep 13 Wed 2017
Tropical Report
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Wed Sep 13 2017
For the North Atlantic…Caribbean Sea and the Gulf of Mexico:
The National Hurricane Center is issuing advisories on Hurricane
Jose, located several hundred miles northeast of the southeastern
Bahamas.
Tropical cyclone formation is not expected during the next 5 days.
$$
Forecaster Pasch
JOSE MOVING SOUTHEASTWARD OVER THE SOUTHWEST ATLANTIC BETWEEN THE BAHAMAS AND BERMUDA
NWS National Hurricane Center Miami FL AL122017
500 AM AST Wed Sep 13 2017
Jose continues to be affected by 20-25 kt of northerly vertical
shear, and a recent GMI overpass shows that the low-level center is
at the northern edge of the convective mass. While the current
organization is that of a system of less than hurricane strength,
the various satellite intensity estimates remain near 65 kt. Thus,
Jose remains a hurricane for this advisory.
The GMI overpass shows that Jose is moving southeastward or 135/7.
A large deep-layer trough to the northeast of the cyclone is
responsible for this motion. However, this trough will soon leave
Jose behind with the subtropical ridge building in to its northwest,
north, and eventually northeast. This evolution should cause Jose
to make a slow clockwise loop during the next 3 days and then turn
northward and northeastward once it moves around the western side of
the ridge. The guidance has come into somewhat better agreement
for this advisory, as the UKMET has shifted eastward from its
Florida landfall forecast and now shows a northward motion along
75W by 120 h. However, there still remains a significant spread
between that model on the left and the ECMWF on the right, which
has Jose closer to 67W by that time. The new forecast track is
similar to the previous track through 72 h, and then it is nudged
just a little to the west of the previous track. The 72-120 h
portion of the forecast track lies west of the HCCA, Florida State
Superensemble, and ECMWF, but lies to the east of the other
consensus models.
the large-scale models forecast the current shear is likely to
persist for at least the next 24 h, followed by some decrease at
about 36-48 h. However, none of the intensity guidance shows
weakening during the first 24 h or much strengthening at 36-48 h.
Second, the cyclone is likely to cross its path, and possibly a wake
of colder sea surface temperatures, between 48-72 h. Third, Jose
should encounter stronger shear after 72 h, but it may interact with
a mid- to upper-level trough over the eastern United States that may
give the system a kick through baroclinic processes. Indeed, the
GFS, UKMET, and ECMWF agree on showing a falling central pressure
from 72-120 h. Based on the overall trend of the guidance, the
intensity forecast is tweaked a little from the previous advisory to
show little change in strength through 48 h and slight weakening
thereafter. However, this is a low-confidence forecast.
FORECAST POSITIONS AND MAX WINDS
INIT 13/0900Z 26.1N 66.0W 65 KT 75 MPH
12H 13/1800Z 25.4N 65.5W 65 KT 75 MPH
24H 14/0600Z 25.0N 65.8W 65 KT 75 MPH
36H 14/1800Z 25.3N 66.9W 65 KT 75 MPH
48H 15/0600Z 26.2N 68.5W 65 KT 75 MPH
72H 16/0600Z 28.0N 71.0W 60 KT 70 MPH
96H 17/0600Z 30.5N 70.5W 60 KT 70 MPH
120H 18/0600Z 33.0N 69.0W 60 KT 70 MPH
$$
Forecaster Beven
NWS National Hurricane Center Miami FL
500 AM PDT Wed Sep 13 2017
For the eastern North Pacific…east of 140 degrees west longitude:
The National Hurricane Center is issuing advisories on Tropical
Depression Fifteen-E, located several hundred miles southwest
of the southern tip of the Baja California peninsula.
1. An area of disturbed weather associated with a low pressure system
is centered just off the southwestern coast of Mexico. This
activity continues to show signs of organization and a tropical
depression is likely to form later today or tomorrow before the
system moves inland over southwestern Mexico. Regardless of
development, locally heavy rains are expected to begin spreading
inland over southwestern Mexico later today. These rains could
cause life-threatening flash floods and mudslides.
* Formation chance through 48 hours…high…80 percent.
* Formation chance through 5 days…high…80 percent.
2. A broad area of low pressure located several hundred miles south of
the southern tip of the Baja California peninsula is producing
disorganized showers and thunderstorms. Environmental conditions
are expected to be conducive for development of this system, and a
tropical depression is likely to form by the end of the week while
it moves slowly northward.
* Formation chance through 48 hours…medium…60 percent.
* Formation chance through 5 days…high…80 percent.
3. Another area of low pressure is located more than 1700 miles
west-southwest of the Baja California peninsula. Development, if
any, of this system is expected to be slow to occur while it
moves little during the next several days.
* Formation chance through 48 hours…low…10 percent.
* Formation chance through 5 days…low…20 percent.
Forecaster Avila
DEPRESSION NEAR TROPICAL STORM STRENGTH
NWS National Hurricane Center Miami FL EP152017
200 AM PDT Wed Sep 13 2017
The overall convective pattern of the depression has changed little
since the previous advisory and remains sheared to the west of the
exposed surface circulation. Displaced intermittent bursts of deep
convection with cloud tops colder than -70C yield an initial shear
pattern intensity estimate of 30 kt, and this is further supported
by a 0540 UTC ASCAT-B scatterometer pass which suggests that the
depression is just below tropical storm strength. The Decay-SHIPS
intensity model and the large-scale deterministic guidance show the
shear gradually diminishing through the entire forecast period.
Accordingly, the official forecast reflects slow strengthening
through 3 days, then little change thereafter, which is just below
the HCCA, DSHP, and the better performing IVCN multi-model
consensus.
A 0201 UTC WindSat image and a 0247 UTC AMSU 89 GHZ composite
overpass were helpful in estimating the position and the initial
motion which is westward, or 270/8 kt. There is no significant
change to the previous track forecast or reasoning. A weakening
low- to mid-level subtropical ridge to the north should steer the
depression generally westward through 48 hours, but with a slight
reduction in speed with time. Beyond 48 hours, the cyclone becomes
trapped in a much weaker steering flow induced by a mid-level ridge
between the depression, a developing system to the east, and a
building high from the northwest. Subsequently, the official
forecast indicates very little motion, or a meander through day 5.
The NHC track forecast is adjusted to the right of the previous
package beyond 24 hours out of respect for the HFIP Corrected
Consensus technique and the ECMWF.
FORECAST POSITIONS AND MAX WINDS
INIT 13/0900Z 14.9N 119.4W 30 KT 35 MPH
12H 13/1800Z 14.9N 120.5W 35 KT 40 MPH
24H 14/0600Z 15.1N 122.0W 35 KT 40 MPH
36H 14/1800Z 15.4N 123.3W 35 KT 40 MPH
48H 15/0600Z 15.5N 124.2W 40 KT 45 MPH
72H 16/0600Z 15.2N 125.2W 45 KT 50 MPH
96H 17/0600Z 15.2N 125.9W 45 KT 50 MPH
120H 18/0600Z 15.5N 126.4W 45 KT 50 MPH
$$
Forecaster Roberts
Weather In Cayman
Synopsis
Sunshine just makes the day a little better, but it can also cause sunburns. Check the UV Report below to be prepared
Humidity: 81% (UP from yesterday)
UV: 12.3 EXTREME (UP from yesterday)
Temperature: Today’s current temperature – See Weather Forecast Top Right of Website. Yesterday: H 90.5°F L 81.3°F
Wind direction TODAY: ESE 5-10 mph GC
Wind direction TONIGHT: E 5-10 mph GC
Barometer: 1014:00 mb Rising slowly Rain: Last month: 4.29 in Last 24 hrs 0.00 This month: 1.91 in
16 Rain days in Aug 6 Rain days in Sep 2 days since rain
2016 Season Total: 20.23 in 2017 Season Total: 25.35 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.
Average rainfall in Sep 8.2 in. Average temperature in Sep: 77°F to 90°F
Sea Temperature in Sep 84°F
Moon: 47% Waning Crescent
TIDES, SUNRISE, SUNSET, MOON RISE, MOON SET AND MOON PHASE
GRAND CAYMAN SEP 2017 – Click to enlarge
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/
http://www.weather.gov.ky/portal/page?_pageid=4421,7428393&_dad=portal&_schema=PORTAL
For Tropical Weather go to:
National Hurricane Center at: http://www.nhc.noaa.gov/
Mike’s Weather Page at: http://www.spaghettimodels.com/