17 Sep Weather in Cayman & Tropical Report, 1 H/cane, 2 TS (Atlantic)
Sep 17 Sun 2017
Tropical Report
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Sun Sep 17 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 south-southeast of Cape
Hatteras, North Carolina, on Tropical Storm Lee, located over the
eastern Atlantic Ocean, and on Tropical Storm Maria, located several
hundred miles east-southeast of the Lesser Antilles.
Tropical cyclone formation is not expected during the next 5 days.
&&
Public Advisories on Tropical Storm Maria are issued under WMO
header WTNT35 KNHC and under AWIPS header MIATCPAT5.
Forecast/Advisories on Tropical Storm Maria are issued under WMO
header WTNT25 KNHC and under AWIPS header MIATCMAT5.
$$
Forecaster Cangialosi
JOSE MOVING A LITTLE FASTER NORTHWARD WITH NO CHANGE IN STRENGTH… …DANGEROUS SURF AND RIP CURRENTS EXPECTED ALONG THE EAST COAST OF THE UNITED STATES
NWS National Hurricane Center Miami FL AL122017
500 AM EDT Sun Sep 17 2017
The satellite presentation of Jose continues to reveal little
change in the overall cloud structure since yesterday afternoon.
The 25-30 kt of westerly shear is inhibiting any further development
of the inner core. Cloud tops have warmed near the center and the
cyclone appears to be tilted toward the northeast with height
in earlier microwave images. Dvorak satellite intensity estimates
remain unchanged from the last advisory, and the initial
intensity is held at 70 kt. Due to the expected shear persisting
through the entire forecast period, the statistical and dynamical
intensity guidance no longer indicate any hint of strengthening,
even in the short term. Accordingly, The NHC forecast reflects
little change in strength through the 48 hour period, then
shows gradual weakening through 5 days.
cyclone is expected to continue on this northward track, along the
western periphery of the Bermuda high, through 48 hours.
Afterward, Jose should gradually turn north-northeastward to
northeastward on days 3 and 4. Near the end of the forecast
period, Jose is forecast to slowly turn eastward within the
mid-latitude, mid-level westerly flow associated with shortwave
trough moving over the Canadian Maritimes. The official forecast
has been adjusted slightly to the west, closer to the HFIP
Corrected Consensus, and near a blend of the UKMET, and ECMWF which
have also shifted a bit westward.
KEY MESSAGES:
1. The center of Jose is forecast to pass well east of the North
Carolina coast on Monday, and tropical-storm-force winds are
currently expected to remain offshore of the North Carolina Outer
Banks. However, an additional increase in the size of the storm or a
westward adjustment in the track forecast could bring tropical storm
conditions closer to the Outer Banks, and interests there should
monitor the progress of Jose through Monday.
2. While Jose is currently forecast to remain offshore of the U.S.
coast from Virginia northward to New England, the large cyclone
could cause some direct impacts to these areas and any deviation to
the left of the NHC forecast track would increase the likelihood and
magnitude of those impacts. Interests along the U.S. east coast
from Virginia to New England should monitor the progress of Jose
through the next several days.
3. Swells generated by Jose are affecting Bermuda, the Bahamas, the
northern coasts of Hispaniola and Puerto Rico, and much of the U.S.
east coast. These swells are likely to cause dangerous surf and rip
current conditions for the next several days in these areas.
FORECAST POSITIONS AND MAX WINDS
INIT 17/0900Z 30.0N 71.7W 70 KT 80 MPH
12H 17/1800Z 31.0N 71.6W 70 KT 80 MPH
24H 18/0600Z 32.5N 71.5W 70 KT 80 MPH
36H 18/1800Z 34.0N 71.5W 65 KT 75 MPH
48H 19/0600Z 35.6N 71.3W 65 KT 75 MPH
72H 20/0600Z 38.6N 70.2W 60 KT 70 MPH
96H 21/0600Z 40.0N 67.4W 50 KT 60 MPH
120H 22/0600Z 39.8N 64.8W 45 KT 50 MPH
$$
Forecaster Roberts
LEE MOVING SLOWLY WESTWARD OVER THE OPEN EASTERN ATLANTIC
NWS National Hurricane Center Miami FL AL142017
500 AM AST Sun Sep 17 2017
Lee remains sheared this morning, with the center of circulation
just beneath the northern edge of the cloud mass. Consequently, the
initial intensity is held at 35 kt and agrees with the subjective
Dvorak intensity estimates from TAFB and SAB. The cyclone is
forecast to remain in an upper wind environment of strong
west-northwesterly shear through the forecast period. The global
and statistical models all show no intensification of Lee through 36
hours or so, followed by a gradual weakening trend through day 5.
In fact, the GFS and ECMWF show dissipation in less than 4 days.
Only the HWRF hurricane model indicates modest strengthening around
the 48 hour period. The official forecast is similar to the
previous package and reflects Lee degenerating into a remnant low in
4 days.
cyclone is currently moving within the easterly mid-level flow
produced by a subtropical ridge anchored to the north. This ridge
is forecast to erode in 36 hours, allowing Lee to gradually turn
west-northwestward and continue tracking in this fashion through 5
days. A slight adjustment to the right of the previous advisory was
made to lie more closely to the HCCA technique and a blend of the
ECMWF and GFS global models.
FORECAST POSITIONS AND MAX WINDS
INIT 17/0900Z 13.0N 35.4W 35 KT 40 MPH
12H 17/1800Z 13.1N 36.4W 35 KT 40 MPH
24H 18/0600Z 13.4N 37.9W 35 KT 40 MPH
36H 18/1800Z 14.2N 39.7W 35 KT 40 MPH
48H 19/0600Z 15.0N 41.3W 30 KT 35 MPH
72H 20/0600Z 17.1N 44.7W 30 KT 35 MPH
96H 21/0600Z 18.9N 48.4W 25 KT 30 MPH…POST-TROP/REMNT LOW
120H 22/0600Z 20.3N 52.3W 20 KT 25 MPH…POST-TROP/REMNT LOW
$$
Forecaster Roberts
MARIA EXPECTED TO BECOME A HURRICANE LATER TODAY
NWS National Hurricane Center Miami FL AL152017
500 AM AST Sun Sep 17 2017
Maria’s cloud pattern is becoming better organized with developing
convective banding features and a gradually expanding CDO.
Upper-level outflow is only slightly restricted over the southern
portion of the circulation. The current intensity is set at 55
kt, in agreement with the latest Dvorak estimates from both TAFB and
SAB. The environment should be conducive for continued
strengthening for the next several days with low shear, a warm
ocean and a fairly moist mid-tropospheric air mass. The official
intensity forecast follows the model consensus, but a more rapid
intensification than indicated here is certainly possible over the
next couple of days.
moving west-northwestward, or 285/13 kt. A mid-level high pressure
area to the north of Maria is forecast to weaken slightly over the
next several days. This should result in a continued
west-northwestward motion with a slowing of forward speed. The
official track forecast is a blend of the latest GFS and ECMWF
predictions, and lies on the left side of the guidance envelope.
KEY MESSAGES:
1. Maria is expected to strengthen and affect portions of the
Leeward Islands as a hurricane early next week, bringing dangerous
wind, storm surge and rainfall hazards. Hurricane or Tropical
Storm Warnings will likely be required for portions of these
islands today.
2. Maria could also affect the British and U.S. Virgin Islands and
Puerto Rico by mid week as a dangerous major hurricane, and
hurricane watches could be issued for these islands as early as
tonight. Interests in these areas should monitor the progress of
Maria and follow any advice given by local officials.
FORECAST POSITIONS AND MAX WINDS
INIT 17/0900Z 13.0N 54.9W 55 KT 65 MPH
12H 17/1800Z 13.7N 56.5W 65 KT 75 MPH
24H 18/0600Z 14.5N 58.3W 75 KT 85 MPH
36H 18/1800Z 15.2N 60.0W 85 KT 100 MPH
48H 19/0600Z 15.8N 61.3W 95 KT 110 MPH
72H 20/0600Z 17.0N 64.0W 110 KT 125 MPH
96H 21/0600Z 18.4N 67.0W 100 KT 115 MPH…INLAND
120H 22/0600Z 19.5N 69.5W 105 KT 120 MPH…OVER WATER
$$
Forecaster Pasch
NWS National Hurricane Center Miami FL
500 AM PDT Sun Sep 17 2017
For the eastern North Pacific…east of 140 degrees west longitude:
The National Hurricane Center is issuing advisories on Tropical
Storm Norma, located south-southwest of the southern tip of the Baja
California peninsula, Mexico, and on Tropical Storm Otis, located
more than 1000 miles west-southwest of the southern tip of the Baja
California peninsula.
Tropical cyclone formation is not expected during the next 5 days.
$$
Forecaster Landsea
WEAKENING NORMA HEADING TOWARD SOUTHERN BAJA CALIFORNIA
NWS National Hurricane Center Miami FL EP172017
300 AM MDT Sun Sep 17 2017
A pair of ASCAT passes between 0400 and 0500 UTC showed that Norma
is weaker than previously estimated. The maximum winds in both
passes were around 40 kt, so the initial intensity has been
conservatively lowered to 45 kt. The new NHC intensity forecast is
a little lower than the previous one because of the lower initial
intensity, but otherwise the reasoning behind the forecast is
unchanged. Norma is already embedded within a fairly dry
environment, and will be moving over progressively cooler SSTs over
the coming days. Steady weakening is likely, and Norma is now
forecast to become a remnant low by 96 h.
There has been a significant shift in the track guidance. The GFS
and various GFS-derived models have come into better agreement with
the ECMWF, and now depict a track farther away from the Baja
California peninsula. Beyond day 3, there is still a fair amount of
disagreement on the extent to which a ridge to the east will turn
the tropical storm or its remnants back toward the north. The ECMWF
continues to insist that the cyclone will come to a near halt, while
the GFS shows the remnant low continuing well to the north. The new
NHC forecast remains close to the various consensus aids, but hedges
toward the ECMWF.
FORECAST POSITIONS AND MAX WINDS
INIT 17/0900Z 20.5N 110.4W 45 KT 50 MPH
12H 17/1800Z 21.1N 110.7W 40 KT 45 MPH
24H 18/0600Z 21.7N 111.3W 40 KT 45 MPH
36H 18/1800Z 22.1N 112.1W 35 KT 40 MPH
48H 19/0600Z 22.4N 113.0W 35 KT 40 MPH
72H 20/0600Z 22.9N 114.3W 30 KT 35 MPH
96H 21/0600Z 23.5N 114.5W 25 KT 30 MPH…POST-TROP/REMNT LOW
120H 22/0600Z 24.0N 114.0W 25 KT 30 MPH…POST-TROP/REMNT LOW
$$
Forecaster Zelinsky
OTIS BARELY MOVING
NWS National Hurricane Center Miami FL EP152017
200 AM PDT Sun Sep 17 2017
Otis continues to exceed my expectations from yesterday. The center
appears to be well embedded within a persistent central dense
overcast, and Dvorak classifications from TAFB and SAB have
increased. On this basis, the intensity has been increased to 45
kt. Otis has an opportunity to strengthen a little bit more over
the next 12 to 24 hours, and the statistical-dynamical models show
this. On the other hand, the HWRF suggests that Otis may have
already peaked. The new forecast splits these scenarios and shows
Otis strengthening only a little more. After that time, SSTs around
26 C and a drier environment should cause the tropical storm to
steadily weaken.
Otis has barely moved overnight, but should begin to slowly lift
northward later this morning. Very little change was required to
the track forecast, and all of the global models continue to
indicate that the cyclone will slowly move into a break in the
subtropical ridge over the next couple of days. After about 72 h,
the remnants of Otis will likely begin to move west-southwestward
within the low-level tradewinds. Although there is a fair amount
of spread on the exact heading Otis will take, there is good
agreement that it won’t move much for the first 72-96 h of the
forecast, so confidence in that aspect of the forecast is fairly
high.
FORECAST POSITIONS AND MAX WINDS
INIT 17/0900Z 16.1N 127.4W 45 KT 50 MPH
12H 17/1800Z 16.6N 127.7W 50 KT 60 MPH
24H 18/0600Z 17.5N 127.7W 50 KT 60 MPH
36H 18/1800Z 18.3N 127.7W 45 KT 50 MPH
48H 19/0600Z 18.8N 127.9W 45 KT 50 MPH
72H 20/0600Z 18.1N 129.3W 35 KT 40 MPH
96H 21/0600Z 17.0N 132.0W 30 KT 35 MPH…POST-TROP/REMNT LOW
120H 22/0600Z 15.5N 136.0W 25 KT 30 MPH…POST-TROP/REMNT LOW
$$
Forecaster Zelinsky
Sunshine just makes the day a little better, but it can also cause sunburns. Check the UV Report below to be prepared
Humidity: 78% (DOWN from yesterday)
UV: 11.9 EXTREME (UP from yesterday)
Temperature: Today’s current temperature – See Weather Forecast Top Right of Website. Yesterday: H 93.1°F L 77.4°F
Wind direction TODAY: E 5-10 mph GC
Wind direction TONIGHT: E 5-10 mph GC
Barometer: 1013:00 mb Rising slowly Rain: Last month: 4.29 in Last 24 hrs 0.01 This month: 3.34 in
16 Rain days in Aug 9 Rain days in Sep 0 days since rain
2016 Season Total: 20.23 in 2017 Season Total: 26.78 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: 9% 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/
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