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6/17/21 

AIM 

FIG 7

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Hawaii Area Forecast Locations 

e.  SIGMET Outside the  CONUS 

1. 

Three NWS offices have been designated by 

ICAO as Meteorological Watch Offices (MWOs). 
These offices are responsible for issuing SIGMETs 
for designated areas outside the CONUS that include 
Alaska, Hawaii, portions of the Atlantic and Pacific 
Oceans, and the Gulf of Mexico. 

2. 

The offices which issue international SIG-

METs are: 

(a) 

The AWC in Kansas City, Missouri. 

(b) 

The AAWU in Anchorage, Alaska. 

(c) 

The WFO in Honolulu, Hawaii. 

3. 

SIGMETs for outside the CONUS are issued 

for 6 hours for volcanic ash clouds, 6 hours for 
tropical cyclones (e.g. hurricanes and tropical 
storms), and 4 hours for all other events. Like the 
CONUS SIGMETs, SIGMETs for outside the 
CONUS are also identified by an alphabetic 
designator from Alpha through Mike and are 
numbered sequentially until that weather phenome-
non ends. The criteria for an international SIGMET 
are: 

(a) 

Thunderstorms occurring in lines, embed-

ded in clouds, or in large areas producing tornadoes 
or large hail. 

(b) 

Tropical cyclones. 

(c) 

Severe icing. 

(d) 

Severe or extreme turbulence. 

(e) 

Dust storms and sandstorms lowering 

visibilities to less than 3 miles. 

(f) 

Volcanic ash. 

EXAMPLE

 

Example of SIGMET Outside the U.S.: 

WSNT06 KKCI 022014 
SIGA0F 
KZMA KZNY TJZS SIGMET FOXTROT 3 VALID 
022015/030015 KKCI

 MIAMI  OCEANIC  FIR  NEW 

YORK OCEANIC FIR SAN JUAN FIR FRQ TS WI AREA 
BOUNDED BY 2711N6807W 2156N6654W 2220N7040W 
2602N7208W 2711N6807W. TOPS TO FL470. MOV NE 
15KT. WKN. BASED ON SAT AND LTG OBS. 
MOSHER 

f.  AIRMET 

1. 

AIRMETs (WAs) are advisories of signifi-

cant weather phenomena but describe conditions at 
intensities lower than those which require the 
issuance of SIGMETs. AIRMETs are intended for 
dissemination to all pilots in the preflight and en route 
phase of flight to enhance safety. AIRMET 
information is available in two formats: text bulletins 
(WA) and graphics (G

AIRMET). Both formats meet 

the criteria of paragraph 7

1

3i and are issued on a 

scheduled basis every 6 hours beginning at 
0245 UTC. Unscheduled updates and corrections are 
issued as necessary. AIRMETs contain details about 

Meteorology 

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