Marine Glossary

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weather report

A description of present and forecasted weather transmitted by some official agency. They are also sometimes called bulletins. They are either broadcast in radio voice over VHF or HF channels or issued in text format via NAVTEX or documents available on USCG computer bulletin boards or the internet. Abbreviated forms sometimes appear in local newspapers.

For US and adjacent waters, weather reports are typically prepared by the National Weather Service and transmitted to mariners by the USCG. Schedules and details are in the Source Book.

See also AM-1603 and synoptic times.

AM-1605 discusses how to coordinate weather reports and weather maps when several sources are available.

A weather report typically includes:

(1) a description of present conditions (called a synopsis) in terms of the locations and movements of pressure systems (High, Low, front, trough, and ridge) as they might appear on a synoptic chart.

(2) a forecast of future conditions, being an extension of the synopsis and actual predictions of wind and seas at various locations. A forecast is sometimes called a prognosis.

(3) warnings of existing or future severe weather (see warning).

(4) a list (sometimes itself called a report) of actual observations of wind, pressure, visibility, temperature, and sea state at various locations across the area covered by that report. Observations are a regular part of NOAA weather radio reports, but are not always included in the coastal sections of high seas reports.

See also long-term forecast.

A sample report from a NAVTEX broadcast is listed below, with several key terms linked to related Glossary discussions. See other sample reports in G442.

FZPN01 KWBC 231624 HSFEP1 (station and report id)
HIGH SEAS FORECAST
NATIONAL WEATHER SERVICE WASHINGTON DC/TPC MIAMI FL MARINE PREDICTION CENTER/MFB 1700 UTC 23 OCT 1996 SUPERSEDED BY NEXT ISSUANCE IN 6 HOURS

SECURITE
PACIFIC N OF 30N AND E OF A LINE FROM THE BERING STRAIT TO 160E.

SYNOPSIS VALID 1200 UTC 23 OCT.
FORECAST VALID 0000 UTC 25 OCT.

WARNINGS
DEVELOPING STORM 56N 159W 986 MB MOVING E 25 KT. WINDS 30 TO 40 KT AND SEAS 14 TO 25 FT WITHIN 480 NM S QUADRANT. WINDS 20 TO 30 KT SEAS 10 TO 16 FT. FORECAST STORM 53N 134W 988 MB. FORECAST WINDS 35 TO 50 KT SEAS 20 TO 30 FT WITHIN 480 NM SW AND S
QUADRANTS. FORECAST WINDS 25 TO 35 KT SEAS 12 TO 22 FT ELSEWHERE N AND E OF A LINE FROM 42N 135W TO 54N 157W.

DEVELOPING STORM 44N 171E 1004 MB MOVING E 30 KT. WINDS 25 TO 35 KT AND SEAS 10 TO 16 FT WITHIN 360 NM SW AND 200 NM NE SEMICIRCLES. FORECAST STORM 49N 176W 980 MB. FORECAST WINDS 40
TO 55 KT SEAS 18 TO 27 FT WITHIN 180 NM NW AND 240 NM SW QUADRANTS. FORECAST WINDS 25 TO 40 KT SEAS 10 TO 18 FT WITHIN 600 NM S AND SE QUADRANTS AND ELSEWHERE WITHIN 420 NM OF CENTER.

BY 240000 UTC GALE 52N 131W MOVING ENE 15 KT. WINDS 25 TO 35 KT SEAS 10 TO 17 FT WITHIN 540 NM S QUADRANT. FORECAST GALE INLAND WITH CONDITIONS MERGING WITH FORECAST STORM 53N 134W.

SYNOPSIS AND FORECAST
LOW 58N 150W 986 MB. EXCEPT AS DESCRIBED ABOVE.. WINDS 20 TO 30 KT SEAS 08 TO 14 FT WITHIN 840 NM SE SEMICIRCLE. FORECAST LOW INLAND.

FORECAST AREA OF NE WINDS 20 TO 30 KT SEAS 09 TO 14 FT WITHIN 300 NM N AND E OF A LINE FROM 59N 165W TO 58N 180 TO 53N 173E.

FORECAST AREA OF WINDS 20 TO 30 KT SEAS 08 TO 13 FT OVER FORECAST WATERS S OF 50N AND W OF 170E.

AREA OF PATCHY DENSE FOG REDUCING VISIBILITY TO LESS THAN ONE NM FROM 38N TO 50N BETWEEN 135W AND 155W. FORECAST AREA OF FOG DISSIPATED.

HIGH 33N 140W 1029 MB NEARLY STATIONARY. FORECAST HIGH 32N 140W 1028 MB.

HIGH 38N 172W 1026 MB MOVING E 20 KT. FORECAST HIGH 41N 147W 1029 MB.
-----------------------

DSP/MARINE FORECAST BRANCH
1630 UTC WED OCT 23 1996

EPAC N OF EQUATOR TO 30N E OF 140W.

SYNOPSIS VALID 1200 UTC WED OCT 23.
FORECAST VALID 0000 UTC FRI OCT 25.

WARNINGS
NONE.

SYNOPSIS AND FORECAST
EPAC N OF 13N W OF 120W WIND NE TO E TO 20 KT AND SEAS 8 TO 10 FT IN SWELLS AT 1200 UTC OCT 23. BY 1800 UTC OCT 23 EPAC FROM 13N TO 27N WIND E TO NE 20 TO 25 KT AND SEAS 8 TO 10 FT IN NE SWELLS.
FORECAST LITTLE CHANGE THROUGH 0000 UTC OCT 25.

EPAC N OF 25N E OF 120W WIND N TO NW TO 20 KT AND SEAS 8 TO 10 FT IN N SWELLS. FORECAST LITTLE CHANGE THROUGH 0000 UTC OCT 25.

EPAC GULF OF TEHUANTEPEC WITHIN 180 NM OF COAST WIND N TO NE 20 TO 25 KT AND SEAS 8 TO 10 FT. FORECAST WINDS LESS THAN 25 KT SEAS
LESS THAN 8 FT AT 0000 UTC OCT 25.

REMAINDER OF EPAC WINDS LESS THAN 20 KT AND SEAS LESS THAN 8 FT THROUGH 0000 UTC OCT 25.

...CONVECTION VALID AS OF 1500 UTC WED OCT 23...

INTERTROPICAL CONVERGENCE ZONE...7N78W 13N100W 9N109W 12N114W 9N 120W 11N140W. SCATTERED MODERATE ISOLATED STRONG 240 NM WIDE 98W
105W AND W OF 135W. SCATTERED MODERATE ISOLATED STRONG 60 NM WIDE 95W 96W AND 120 NM WIDE 107W 113W. SCATTERED MODERATE 60 NM WIDE
81W 87W.