National Weather Service United States Department of Commerce

Powerful Pacific System Impacting the West; First Significant Snow for Portions of the East

Power Pacific system will continue to bring significant impacts for Pacific Northwest into northern California the remainder of the week. Dangerous coastal affects, heavy rain, flooding, strong winds, and higher elevation mountain snow continues. Meanwhile, a storm across the east is set to bring the first accumulating snow to many higher elevations of the Catskills into the central Appalachians. Read More >


	EXPERIMENTAL...FIRE WEATHER POINT FORECAST MATRICES
NATIONAL WEATHER SERVICE Wakefield VA
410 PM EST Thu Nov 21 2024

EXPERIMENTAL ONLY...THIS PRODUCT IS FOR PLANNING AND REVIEW PURPOSES ONLY AND
IS NOT TO BE SUBSTITUTED FOR AN OFFICIAL FIRE WEATHER SPOT
FORECAST.
BELOW IS A WEATHER ELEMENT KEY FOR THIS PRODUCT.
(NOTE...WINDS DO NOT REFLECT LOCAL TERRAIN EFFECTS.)

DAY 1 THROUGH 3...
MAX/MIN TEMP or MIN/MAX TEMP(F).....MAXIMUM/MINIMUM AIR TEMPERATURE
TEMP(F).............................AIR TEMPERATURE
DEWPT(F)............................DEW POINT TEMPERATURE
MIN/MAX RH or MAX/MIN RH(%).........MAXIMUM/MINIMUM HUMIDITY
RH(%)...............................RELATIVE HUMIDITY
WIND DIR(8 POINT COMPASS)...........20 FT. WIND DIRECTION
WIND DIR DEG(DEGREES)...............20 FT. WIND DIRECTION IN TENS OF DEGREES
                                    RELATIVE TO DUE NORTH.
     EXAMPLE: 09 = 90 DEGREES = EAST; 18 = 180 DEGREES = SOUTH;
              27 = 270 DEGREES = WEST; 36 = 360 DEGREES = NORTH
WIND SPD(MPH).......................20 FT. WIND SPEED
WIND GUST(MPH)......................20 FT. WIND GUST
WIND CHILL..........................WIND CHILL TEMPERATURE
HEAT INDX...........................HEAT INDEX
CLOUDS(CAT).........................CLOUD COVER CATEGORY
     EXAMPLE: CL = CLEAR; FW = FEW; SC = SCATTERED;
              B1 = MOSTLY CLOUDY; B2 = CONSIDERABLE CLOUDS; OV = OVERCAST
CLOUDS(%)...........................CLOUD COVER AS A PERCENTAGE
VSBY................................VISIBILITY VALUE IN STATUTE MILES
POP 12HR(%).........................PROBABILITY FOR ACCUMULATING PRECIPITATION
QPF 12HR(IN)........................LIQUID EQUIVALENT PRECIPITATION AMOUNT
WEATHER...
     TYPE...
       RAIN...........RAIN
       RAIN SHWRS.....RAIN SHOWERS
       TSTMS..........THUNDERSTORMS
       DRIZZLE........DRIZZLE
       SNOW...........SNOW
       SNOWSHWRS......SNOW SHOWERS
       SLEET..........SLEET
       FLURRIES.......FLURRIES
       FRZG RAIN......FREEZING RAIN
       FRZG DRZL......FREEZING DRIZZLE
     COVERAGE...
       S..............SLIGHT CHANCE
       C..............CHANCE
       L..............LIKELY
       O..............OCCASIONAL
       D..............DEFINITE
       AR.............AREAS
       PA.............PATCHY
OBVIS...............................OBSTRUCTION TO VISIBILITY
     TYPE...
       F..............FOG
       PF.............PATCHY FOG
       F+.............DENSE FOG
       H..............HAZE
       BS.............BLOWING SNOW
       K..............SMOKE
       BD.............BLOWING DUST
       AF.............VOLCANIC ASHFALL
LAL(CAT)............................LIGHTNING ACTIVITY LEVEL
HAINES(CAT).........................HAINES INDEX
MIX HGT(FT AGL).....................MIXING HEIGHT
T WIND DIR(8 POINT COMPASS).........TRANSPORT WIND DIRECTION
T WIND SPD(MPH).....................TRANSPORT WIND SPEED
SMOKE DISPERSION....................SMOKE DISPERSION CATEGORY
     VALUES: VP = VERY POOR; PR = POOR; FR = FAIR; GD = GOOD
ADI (INDEX).........................ATMOSPHERIC DISPERSION INDEX
CEILING (FT)........................CEILING
PRESSURE (INCHES MERCURY)...........STATION PRESSURE
MAX LVORI (INDEX)...................LOW VISIBILITY OCCURRENCE RISK INDEX
STABILITY (CAT).....................PASQUILL TURNER STABILITY
WATCH/WARNING/ADVISORY...
     EXAMPLE: W = WARNING; Y = ADVISORY; A = WATCH
     IN EFFECT FOR THE INDICATED HOUR 

DAY 4 THROUGH 7...
MAX/MIN TEMP or MIN/MAX TEMP(F).....MAXIMUM/MINIMUM AIR TEMPERATURE
TEMP(F).............................AIR TEMPERATURE
DEWPT(F)............................DEW POINT TEMPERATURE
RH(%)...............................RELATIVE HUMIDITY
WIND DIR............................20 FT. WIND DIRECTION
WIND SPD(MPH).......................20 FT. WIND SPEED
AVG CLOUDS(CAT).....................AVERAGE CLOUD COVER CATEGORY
POP 12HR(%).........................PROBABILITY FOR ACCUMULATING PRECIPITATION
WEATHER...
     SEE DAY 1 THROUGH 3 WEATHER DESCRIPTIONS