Aerial view of Harbour Island Bahamas weather.

Weather Forecast for Harbour Island

Current conditions, average weather and storm reports.

What is the weather forecast for Harbour Island?

Currently: Mostly Cloudy: 86F
Currently in Dunmore Town, BS: 86 °F and Mostly Cloudy

9/23/2021 Forecast
High: 87 F Low: 79 F Some sun with a few showers

9/24/2021 Forecast
High: 85 F Low: 78 F A shower and thunderstorm

Harbour Island Accuweather 25 Day Forecast

What is Average Temperature for Harbour Island?

Monthly Weather Averages

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mean Daily Maximum Temperature - F°
76 79 80 82 86 86 89 90 89 88 83 80
Mean Daily Minimum Temperature - F°
65 68 66 69 73 76 79 78 74 75 73 68
Monthly Rainfall - Inches
3.4 3.2 2.2 .96 4.0 1.2 3.0 5.5 1.3 4.3 5.4 3.1
Number of Rain Days
6 4 3 3 5 2 4 7 4 6 8 7

Weather Radar for Harbour Island

Wunderground Caribbean Radar Map

Real Time GOES Imagery - Definitive Weather Satellite Views of the Bahamas and Caribbean:

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Sea Surface Temperature

Space, Science & Engineering's Interactive Geostationary Real Time Satellite Images

Current Hurricane Reports for the Bahamas

National Hurricane Center

NHC Atlantic

Active tropical cyclones in the Atlantic, Caribbean, and the Gulf of Mexico

Atlantic Tropical Weather Outlook


000
ABNT20 KNHC 231753
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Thu Sep 23 2021

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

The National Hurricane Center is issuing advisories on recently
upgraded Tropical Storm Sam, located about 1700 miles east-southeast
of the northern Leeward Islands.

A gale-force, non-tropical low pressure system, the remnants of
Odette, is located a little more than 600 miles west-northwest of
the westernmost Azores. While showers and thunderstorms remain
limited near the low, only a small increase in this activity could
result in the formation of a subtropical or tropical cyclone while
it moves generally southward over marginally warmer waters during
the next day or so. Strong upper-level winds are expected to
develop over the system beginning tomorrow, which should then limit
further development. Additional information on this system,
including gale warnings, can be found in High Seas Forecasts issued
by the National Weather Service.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...medium...60 percent.

A surface trough of low pressure has developed in association with a
large area of showers and thunderstorms located a few hundred miles
southeast of Bermuda. This feature is interacting with an
upper-level trough, and some tropical or subtropical development
could occur in the next day or two as this feature moves generally
north-northwestward. Strong upper-level winds should prohibit
further development by this weekend.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 5 days...low...10 percent.

A tropical wave is expected to move off the west coast of
Africa by the end of this weekend. Thereafter, environmental
conditions are forecast to be conducive for gradual development of
this system as it moves westward at 10 to 15 mph over the far east
Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...low...30 percent.

&&

Public Advisories on Tropical Storm Sam are issued under
WMO header WTNT33 KNHC and under AWIPS header MIATCPAT3.
Forecast/Advisories on Tropical Storm Sam are issued
under WMO header WTNT23 KNHC and under AWIPS header MIATCMAT3.

High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Papin

Posted on 23 September 2021 | 12:53 pm

Tropical Storm Sam Forecast Discussion Number 4

Issued at 1100 AM AST Thu Sep 23 2021


000
WTNT43 KNHC 231500
TCDAT3
 
Tropical Storm Sam Discussion Number   4
NWS National Hurricane Center Miami FL       AL182021
1100 AM AST Thu Sep 23 2021
 
Overnight and this morning, the satellite structure of the tropical
cyclone has been improving, with prominent curved bands, and obvious
low-level cloud motions that indicate the circulation is becoming
established within the convection. In particular, an SSMIS microwave
pass at 0653 UTC indicated a substantial improvement in the
convective structure, with a well-defined curved band wrapping
three-quarters of the way around the center in both the 91- and
37-GHz channels. ASCAT-B wind retrievals at 1234 UTC also indicated
a tight, well-defined circulation had formed, with peak winds of
44-kt on the north side of the vortex. Subjective Dvorak satellite
intensity estimates are now T3.5/55-kt from SAB and T2.5/35-kt from
TAFB. In addition, the latest objective intensity estimates from
UW-CIMSS ADT and SATCON were at 35-kt and 43-kt respectively. Given
the recent scatterometer data, the intensity has been set to 45-kt
for this advisory. Thus, Tropical Depression 18 has been upgraded to
Tropical Storm Sam. It is noteworthy that this is the 2nd earliest
formation of the 18th named storm in the Atlantic basin, moving
ahead of the 2005 hurricane season, and only trailing last year.
 
Sam continues to move to the west-northwest with an estimated motion
at 280/14 kt.  A prominent mid-level ridge remains entrenched to the
north of the cyclone, and this feature should continue to steer Sam
to the west-northwest over the next 2-3 days. Over this period, the
ridge orientation actually shifts more westward ahead of the cyclone
as a deep-layer trough digs in well northeast of Sam. This gradual
change in the synoptic pattern should also result in a slowdown in
Sam's forward motion over the next 72 hours. While the track
guidance remains in good agreement over this period, larger spread
begins to take shape beyond the day 3 forecast. Similar to
yesterday, the ECMWF model and its ensemble mean flanks the
southwest side of the guidance envelop, while the GFS is on the
northeast side by day 5. These differences appear to be partially
related to the mid-level ridge intensity on the western end, which
could begin to be eroded by a mid-latitude trough off the eastern
United States in 120-h. In addition, differences in both the size
and intensity of Sam may also play a role in its ultimate track
evolution. For this advisory, the latest NHC track forecast remains
close to the consensus aids TCVN and TCVE, which represents a slight
shift westward and a bit faster motion compared to the previous
forecast. Because Sam is forecast to slow down, it remains too early
to determine what impacts, direct or indirect, could be felt by the
Lesser Antilles by this cyclone.
 
The previously mentioned SSMIS microwave imagery also indicated that
the low-level center has become better aligned with the mid-level
vortex, perhaps a bit earlier than anticipated given the
scatterometer data from last night. This improvement in structure,
combined with favorable low vertical wind shear under 10 kt and warm
28-29 C sea-surface temperatures, argues for significant
intensification. In fact, the GFS-SHIPS rapid intensification index
now give Sam a 39 percent chance of a 65-kt increase over the next
72 hours, which is more than 7 times the climatological value. Thus,
the NHC intensity forecast has been raised quite a bit from the
prior one, especially in the short-term. The latest forecast now
makes Sam a hurricane in 36 hours, and a major hurricane in 72
hours. This intensity forecast is just a shade under the latest HCCA
consensus aid. Thereafter, a more gradual intensification rate is
forecast. By this period it is possible that Sam could undergo hard
to predict inner-core changes such as eyewall replacement cycles. In
addition, the ECMWF-SHIPS suggests that the shear may also increase
a little in days 4-5 which also argues for a bit slower rate of
intensification for this period.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  23/1500Z 10.9N  38.1W   45 KT  50 MPH
 12H  24/0000Z 11.3N  40.3W   50 KT  60 MPH
 24H  24/1200Z 11.9N  42.9W   60 KT  70 MPH
 36H  25/0000Z 12.3N  45.0W   70 KT  80 MPH
 48H  25/1200Z 12.7N  46.7W   80 KT  90 MPH
 60H  26/0000Z 13.2N  48.2W   90 KT 105 MPH
 72H  26/1200Z 13.7N  49.4W  100 KT 115 MPH
 96H  27/1200Z 15.3N  52.1W  105 KT 120 MPH
120H  28/1200Z 17.4N  55.2W  110 KT 125 MPH
 
$$
Forecaster Papin
 

Posted on 23 September 2021 | 10:00 am

Tropical Storm Sam Graphics

Tropical Storm Sam 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Thu, 23 Sep 2021 14:56:52 GMT

Tropical Storm Sam 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Thu, 23 Sep 2021 15:22:59 GMT

Posted on 23 September 2021 | 9:56 am

Tropical Storm Sam Wind Speed Probabilities Number 4

Issued at 1500 UTC THU SEP 23 2021


000
FONT13 KNHC 231456
PWSAT3
                                                                    
TROPICAL STORM SAM WIND SPEED PROBABILITIES NUMBER   4              
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182021               
1500 UTC THU SEP 23 2021                                            
                                                                    
AT 1500Z THE CENTER OF TROPICAL STORM SAM WAS LOCATED NEAR LATITUDE 
10.9 NORTH...LONGITUDE 38.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR  
45 KTS...50 MPH...85 KM/H.                                          
                                                                    
Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH)                  
   ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME      
   EASTERN  DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME      
   CENTRAL  DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME      
                                                                    
WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS                 
                                                                    
CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST     
   ...34 KT (39 MPH... 63 KM/H)...                                  
   ...50 KT (58 MPH... 93 KM/H)...                                  
   ...64 KT (74 MPH...119 KM/H)...                                  
FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS               
                                                                    
PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE               
    OP  IS THE PROBABILITY OF THE EVENT BEGINNING DURING            
        AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY)               
   (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN           
        12Z THU AND THE FORECAST HOUR (CUMULATIVE PROBABILITY)      
                                                                    
PROBABILITIES ARE GIVEN IN PERCENT                                  
X INDICATES PROBABILITIES LESS THAN 1 PERCENT                       
PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN
THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT.             
PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY              
64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT.                 
                                                                    
                                                                    
  - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - -   
                                                                    
               FROM    FROM    FROM    FROM    FROM    FROM    FROM 
  TIME       12Z THU 00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             00Z FRI 12Z FRI 00Z SAT 12Z SAT 12Z SUN 12Z MON 12Z TUE
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
BARBUDA        34  X   X( X)   X( X)   X( X)   X( X)   X( X)   4( 4)
 
ANTIGUA        34  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)
 
GUADELOUPE     34  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)
 
DOMINICA       34  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)
 
MARTINIQUE     34  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)
 
BARBADOS       34  X   X( X)   X( X)   X( X)   X( X)   X( X)   3( 3)
 
$$                                                                  
FORECASTER PAPIN                                                    

Posted on 23 September 2021 | 9:56 am

Summary for Tropical Storm Sam (AT3/AL182021)

...DEPRESSION STRENGTHENS INTO TROPICAL STORM SAM, THE 18TH NAMED STORM OF THE SEASON... ...NOW FORECAST TO BECOME A HURRICANE TOMORROW... As of 11:00 AM AST Thu Sep 23 the center of Sam was located near 10.9, -38.1 with movement W at 16 mph. The minimum central pressure was 1003 mb with maximum sustained winds of about 50 mph.

Posted on 23 September 2021 | 9:55 am

Tropical Storm Sam Public Advisory Number 4

Issued at 1100 AM AST Thu Sep 23 2021


000
WTNT33 KNHC 231455
TCPAT3
 
BULLETIN
Tropical Storm Sam Advisory Number   4
NWS National Hurricane Center Miami FL       AL182021
1100 AM AST Thu Sep 23 2021
 
...DEPRESSION STRENGTHENS INTO TROPICAL STORM SAM, THE 18TH NAMED
STORM OF THE SEASON...
...NOW FORECAST TO BECOME A HURRICANE TOMORROW...
 
 
SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...10.9N 38.1W
ABOUT 1745 MI...2805 KM ESE OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...W OR 280 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 1100 AM AST (1500 UTC), the center of Tropical Storm Sam was
located near latitude 10.9 North, longitude 38.1 West. Sam is moving
toward the west near 16 mph (26 km/h) and this general motion is
expected to continue over the next several days, but with a gradual
slowdown in forward motion.
 
Recent sallite wind data indicates maximum sustained winds have
increased to near 50 mph (85 km/h) with higher gusts. Additional
strengthening is forecast over the next several days, and Sam is now
forecast to become a hurricane tomorrow and be near major hurricane
intensity by the end of the weekend.
 
Tropical-storm-force winds extend outward up to 45 miles (75 km)
from the center.
 
The estimated minimum central pressure is 1003 mb (29.62 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
None.
 
 
NEXT ADVISORY
-------------
Next complete advisory at 500 PM AST.
 
$$
Forecaster Papin
 

Posted on 23 September 2021 | 9:55 am

Tropical Storm Sam Forecast Advisory Number 4

Issued at 1500 UTC THU SEP 23 2021


245 
WTNT23 KNHC 231454
TCMAT3
 
TROPICAL STORM SAM FORECAST/ADVISORY NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182021
1500 UTC THU SEP 23 2021
 
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
 
TROPICAL STORM CENTER LOCATED NEAR 10.9N  38.1W AT 23/1500Z
POSITION ACCURATE WITHIN  20 NM
 
PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT  14 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1003 MB
MAX SUSTAINED WINDS  45 KT WITH GUSTS TO  55 KT.
34 KT....... 40NE   0SE   0SW  40NW.
12 FT SEAS.. 60NE   0SE   0SW  30NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT.  RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.
 
REPEAT...CENTER LOCATED NEAR 10.9N  38.1W AT 23/1500Z
AT 23/1200Z CENTER WAS LOCATED NEAR 10.8N  37.4W
 
FORECAST VALID 24/0000Z 11.3N  40.3W
MAX WIND  50 KT...GUSTS  60 KT.
50 KT... 30NE   0SE   0SW   0NW.
34 KT... 50NE  40SE   0SW  50NW.
 
FORECAST VALID 24/1200Z 11.9N  42.9W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 30NE   0SE   0SW  20NW.
34 KT... 60NE  40SE   0SW  50NW.
 
FORECAST VALID 25/0000Z 12.3N  45.0W
MAX WIND  70 KT...GUSTS  85 KT.
64 KT... 20NE   0SE   0SW   0NW.
50 KT... 30NE  30SE   0SW  30NW.
34 KT... 70NE  40SE  30SW  50NW.
 
FORECAST VALID 25/1200Z 12.7N  46.7W
MAX WIND  80 KT...GUSTS 100 KT.
64 KT... 20NE  20SE   0SW  20NW.
50 KT... 30NE  30SE  20SW  30NW.
34 KT... 80NE  60SE  40SW  70NW.
 
FORECAST VALID 26/0000Z 13.2N  48.2W
MAX WIND  90 KT...GUSTS 110 KT.
50 KT... 40NE  30SE  20SW  30NW.
34 KT... 90NE  70SE  50SW  70NW.
 
FORECAST VALID 26/1200Z 13.7N  49.4W
MAX WIND 100 KT...GUSTS 120 KT.
50 KT... 50NE  40SE  40SW  50NW.
34 KT... 90NE  80SE  60SW  80NW.
 
EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY
 
OUTLOOK VALID 27/1200Z 15.3N  52.1W
MAX WIND 105 KT...GUSTS 130 KT.
 
OUTLOOK VALID 28/1200Z 17.4N  55.2W
MAX WIND 110 KT...GUSTS 135 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 10.9N  38.1W
 
NEXT ADVISORY AT 23/2100Z
 
$$
FORECASTER PAPIN
 
 

Posted on 23 September 2021 | 9:54 am