“Excessive heat watch”的意思、由来-开放百科全书

An Excessive Heat Watch is issued by the National Weather Service of the United States when the heat index is expected to be greater than 105 °F (41 °C) across the northern states or 110 °F (43 °C) across the southern states during the day, and/or nighttime low temperature will be at least 75 °F (24 °C) or higher for two consecutive days. Note that even with the usual northern/southern criteria, local offices, particularly those with deserts or mountainous terrain, often have their own criteria. High values of the heat index are caused by temperatures being significantly above normal and high humidities, and such high levels can pose a threat to human life through conditions such as heat stroke.^[1]

Example

The following is an example of an Excessive Heat Watch issued by the National Weather Service office in Memphis, Tennessee.^[2]

789 WWUS74 KMEG 130142NPWMEGURGENT - WEATHER MESSAGENATIONAL WEATHER SERVICE MEMPHIS TN842 PM CDT MON JUL 12 2010...VERY HOT AND HUMID CONDITIONS POSSIBLE WEDNESDAY THROUGHTHURSDAY....A LARGE...HOT RIDGE OF HIGH PRESSURE WILL BUILD OVER THE LOWERMISSISSIPPI RIVER VALLEY DURING THE MIDDLE OF THE WEEK. HOTTEMPERATURES IN COMBINATION WITH A VERY HUMID AIRMASS LEFT INPLACE BY RECENT HEAVY RAINS WILL BRING THE MOST STIFLING AIRMASSTO PORTIONS OF THE MIDSOUTH SO FAR THIS SUMMER.ARZ008-009-017-018-026>028-035-036-048-049-058-MOZ113-115-MSZ001-002-007-008-010>013-020-021-TNZ001-002-019-048>051-088-089-130945-/O.NEW.KMEG.EH.A.0001.100714T1500Z-100716T0300Z/RANDOLPH-CLAY-LAWRENCE-GREENE-CRAIGHEAD-POINSETT-MISSISSIPPI-CROSS-CRITTENDEN-ST. FRANCIS-LEE AR-PHILLIPS-DUNKLIN-PEMISCOT-DESOTO-MARSHALL-TUNICA-TATE-COAHOMA-QUITMAN-PANOLA-LAFAYETTE-TALLAHATCHIE-YALOBUSHA-LAKE-OBION-DYER-LAUDERDALE-TIPTON-HAYWOOD-CROCKETT-SHELBY-FAYETTE-INCLUDING THE CITIES OF...WALNUT RIDGE...PARAGOULD...JONESBORO...HARRISBURG...BLYTHEVILLE...WYNNE...WEST MEMPHIS...FORREST CITY...HELENA...KENNETT...CARUTHERSVILLE...SOUTHAVEN...OLIVE BRANCH...TUNICA...CLARKSDALE...BATESVILLE...OXFORD...UNION CITY...DYERSBURG...COVINGTON...BARTLETT...GERMANTOWN...COLLIERVILLE...MEMPHIS...MILLINGTON...SOMERVILLE842 PM CDT MON JUL 12 2010...EXCESSIVE HEAT WATCH IN EFFECT FROM WEDNESDAY MORNING THROUGHTHURSDAY EVENING...THE NATIONAL WEATHER SERVICE IN MEMPHIS HAS ISSUED AN EXCESSIVEHEAT WATCH...WHICH IS IN EFFECT FROM WEDNESDAY MORNING THROUGHTHURSDAY EVENING.* HEAT INDEX READINGS OF 107 TO 112 DEGREES WILL RESULT FROM DAYTIME TEMPERATURES IN THE MID TO UPPER 90S AND DEW POINTS IN THE MID TO UPPER 70S. LITTLE RELIEF CAN BE EXPECTED WEDNESDAY NIGHT WITH LOWS REMAINING ABOVE 75 DEGREES...AND POSSIBLY 80 DEGREES IN DOWNTOWN MEMPHIS.* THE HIGHEST HEAT INDEX READINGS WILL BE FELT BETWEEN 1 PM AND 6 PM WEDNESDAY AND THURSDAY AFTERNOONS.* HEAT INDEX READINGS AROUND 110 DEGREES CAN BE A VERY DANGEROUS SITUATION IF PRECAUTIONS ARE NOT TAKEN. HEAT IS THE NUMBER ONE WEATHER KILLER. HEAT RELATED ILLNESSES ARE LIKELY IN THESE CONDITIONS FOR ALL PEOPLE WITH PROLONGED EXPOSURE TO THE HEAT. YOUNG CHILDREN...ELDERLY PEOPLE...THOSE WITH ILLNESSES OR HEART CONDITIONS...AND THOSE WHO WORK OUTDOORS ARE ESPECIALLY AT RISK.PRECAUTIONARY/PREPAREDNESS ACTIONS...AN EXCESSIVE HEAT WATCH MEANS THAT A PROLONGED PERIOD OF HOTTEMPERATURES IS EXPECTED. THE COMBINATION OF HOT TEMPERATURES ANDHIGH HUMIDITY WILL COMBINE TO CREATE A DANGEROUS SITUATION INWHICH HEAT ILLNESSES ARE POSSIBLE. DRINK PLENTY OF FLUIDS...STAYIN AN AIR-CONDITIONED ROOM...STAY OUT OF THE SUN...AND CHECK UPON RELATIVES AND NEIGHBORS.&&$$BORGHOFF

Example

See also

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