896
FNUS55 KPSR 181026
FWFPSR
FIRE WEATHER PLANNING FORECAST FOR SOUTHWEST AND SOUTH-CENTRAL
ARIZONA AND SOUTHEAST CALIFORNIA
NATIONAL WEATHER SERVICE PHOENIX AZ
326 AM MST MON MAY 18 2026
DISCUSSION
ELEVATED AND MARGINALLY CRITICAL FIRE WEATHER CONDITIONS ARE
EXPECTED EARLY THIS MORNING ACROSS PORTIONS OF SOUTHEAST CA AS A
RESULT OF STRONG NORTHERLY WINDS AND DRY AIR FOLLOWING A FRONTAL
PASSAGE. CONDITIONS WILL IMPROVE BY LATE-MORNING/EARLY-AFTERNOON
AS NORTHERLY WINDS SUBSIDE. ELSEWHERE TODAY, WINDS WILL BE
LIGHTER, BUT STILL WITH PEAK SOUTHWESTERLY GUSTS UP TO 15-30 MPH
ACROSS SOUTH-CENTRAL AZ. MINIMUM RH VALUES TODAY WILL BE AROUND
5-10% ACROSS WESTERN DISTRICTS TO 15-25% ACROSS EASTERN DISTRICTS.
TEMPERATURES WILL BE COOLEST, AND BELOW NORMAL, TODAY, WHICH WILL
RESULT LOWER MAX MIXING HEIGHTS MOST OF THE DAY (UP TO 6-8K FT
ABOVE GROUND LEVEL). TEMPERATURES WARM SLIGHTLY INTO TOMORROW, BUT
WILL REMAIN JUST BELOW NORMAL. CONDITIONS WILL REMAIN DRY
TOMORROW WITH MINIMUM RH VALUES AROUND 5-15%. OVERNIGHT RECOVERY
TONIGHT WILL POOR TO FAIR AT 20-40%. WINDS TOMORROW WILL BE
LIGHTER WITH TYPICAL AFTERNOON UPSLOPE BREEZES UP TO 15-25 MPH IN
MOST AREAS. THE ONLY EXCEPTION WILL BE ANOTHER BRIEF ENHANCED
NORTHERLY WIND DOWN THE COLORADO RIVER TOMORROW MORNING. THERE IS
NO RAIN IN THE FORECAST.
NOTE...ADDITIONAL FIRE WEATHER FORECAST INFORMATION CAN BE FOUND
IN THE AREA FORECAST DISCUSSION. SEE PRODUCT PHXAFDPSR.
AZZ132-182230-
WEST CENTRAL DESERTS/NORTHWEST MARICOPA COUNTY/GREATER PHOENIX
AREA/SOUTHWEST DESERTS/SOUTHWEST MARICOPA COUNTY/
NORTHWEST AND NORTH-CENTRAL PINAL COUNTY-
PHOENIX BLM/YUM BLM/CAZ-CRZ-
326 AM MST MON MAY 18 2026
TODAY
* SKY/WEATHER.....................SUNNY.
* MAX TEMPERATURE.................81-88.
* 24 HR TREND..................5 DEGREES COOLER.
* MIN HUMIDITY....................9-17 PCT.
* 24 HR TREND..................4 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..WEST 5 TO 15 MPH.
* WINDS...10000 FT MSL............WEST 20 TO 30 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
* MIXING HEIGHT FOR PHOENIX.......9800 FT AGL.
* TRANSPORT WIND FOR PHOENIX......SOUTHWEST 13 KNOTS.
* DISPERSION FOR PHOENIX..........EXCELLENT.
TONIGHT
* SKY/WEATHER.....................CLEAR.
* MIN TEMPERATURE.................55-65.
* 24 HR TREND..................LITTLE CHANGE.
* MAX HUMIDITY....................18-41 PCT.
* 24 HR TREND..................24 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..WEST 5 TO 15 MPH.
* WINDS...10000 FT MSL............WEST 10 TO 20 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TUESDAY
* SKY/WEATHER.....................MOSTLY SUNNY.
* MAX TEMPERATURE.................86-92.
* 24 HR TREND..................5 DEGREES WARMER.
* MIN HUMIDITY....................7-11 PCT.
* 24 HR TREND..................3 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..EAST 5 TO 10 MPH IN THE MORNING
BECOMING WEST IN THE AFTERNOON.
* WINDS...10000 FT MSL............SOUTHWEST 10 TO 15 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
* MIXING HEIGHT FOR PHOENIX.......10300 FT AGL.
* TRANSPORT WIND FOR PHOENIX......SOUTHWEST 8 KNOTS.
* DISPERSION FOR PHOENIX..........VERY GOOD.
EXTENDED
WEDNESDAY
MOSTLY CLEAR. LOWS 59-69. HIGHS 90-96. SOUTHWEST
WINDS 5 TO 10 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN
15 PERCENT.
THURSDAY
CLEAR. LOWS 60-70. HIGHS 91-97. SOUTH WINDS 5 TO
10 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
FRIDAY
CLEAR. LOWS 62-72. HIGHS 92-98. SOUTH WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
SATURDAY
CLEAR. LOWS 62-72. HIGHS 92-99.
SUNDAY
CLEAR. LOWS 63-73. HIGHS 94-100.
AZZ131-CAZ231-182230-
YUMA/MARTINEZ LAKE AND VICINITY/LOWER COLORADO RIVER VALLEY AZ-
LOWER COLORADO RIVER VALLEY CA-
326 AM MST MON MAY 18 2026 /326 AM PDT MON MAY 18 2026/
TODAY
* SKY/WEATHER.....................SUNNY. PATCHY BLOWING DUST IN THE
MORNING.
* MAX TEMPERATURE.................83-88.
* 24 HR TREND..................6 DEGREES COOLER.
* MIN HUMIDITY....................7-12 PCT.
* 24 HR TREND..................7 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 10 TO 20 MPH.
* WINDS...10000 FT MSL............WEST 20 TO 30 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
* MIXING HEIGHT FOR YUMA..........9700 FT AGL.
* TRANSPORT WIND FOR YUMA.........NORTHWEST 9 KNOTS.
* DISPERSION FOR YUMA.............VERY GOOD.
TONIGHT
* SKY/WEATHER.....................CLEAR.
* MIN TEMPERATURE.................55-61.
* 24 HR TREND..................3 DEGREES COOLER.
* MAX HUMIDITY....................20-41 PCT.
* 24 HR TREND..................16 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 5 TO 15 MPH.
* WINDS...10000 FT MSL............WEST 10 TO 20 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TUESDAY
* SKY/WEATHER.....................MOSTLY SUNNY.
* MAX TEMPERATURE.................89-94.
* 24 HR TREND..................6 DEGREES WARMER.
* MIN HUMIDITY....................6-10 PCT.
* 24 HR TREND..................LITTLE RH CHANGE.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 5 TO 15 MPH.
* WINDS...10000 FT MSL............NORTHWEST 5 TO 15 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
* MIXING HEIGHT FOR YUMA..........10500 FT AGL.
* TRANSPORT WIND FOR YUMA.........SOUTHWEST 6 KNOTS.
* DISPERSION FOR YUMA.............MARGINAL.
EXTENDED
WEDNESDAY
CLEAR. LOWS 57-65. HIGHS 93-98. WEST WINDS 5 TO
10 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
THURSDAY
CLEAR. LOWS 60-67. HIGHS 94-99. SOUTH WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
FRIDAY
CLEAR. LOWS 62-67. HIGHS 95-100. SOUTH WINDS 10 TO
20 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
SATURDAY
CLEAR. LOWS 62-67. HIGHS 95-100.
SUNDAY
CLEAR. LOWS 63-69. HIGHS 96-101.
AZZ133-182230-
SOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLS-
SOUTHERN TONTO NF/WEST SAN CARLOS BIA/SOUTH PORTION FT APACHE BIA/
CAZ-
326 AM MST MON MAY 18 2026
TODAY
* SKY/WEATHER.....................SUNNY.
* MAX TEMPERATURE.................70-84.
* 24 HR TREND..................6 DEGREES COOLER.
* MIN HUMIDITY....................17-26 PCT.
* 24 HR TREND..................9 PCT WETTER.
* WINDS - 20 FOOT...SLOPE/VALLEY..SOUTHWEST 10 TO 20 MPH.
* WINDS...10000 FT MSL............SOUTHWEST 30 TO 40 MPH IN THE
MORNING BECOMING 15 TO 25 MPH IN THE AFTERNOON.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TONIGHT
* SKY/WEATHER.....................CLEAR.
* MIN TEMPERATURE.................45-61.
* 24 HR TREND..................LITTLE CHANGE.
* MAX HUMIDITY....................32-53 PCT.
* 24 HR TREND..................10 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..WEST 5 TO 10 MPH IN THE EVENING
BECOMING MOSTLY DOWNSLOPE/DOWNVALLEY AFTER MIDNIGHT.
* WINDS...10000 FT MSL............SOUTHWEST 20 TO 30 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TUESDAY
* SKY/WEATHER.....................SUNNY.
* MAX TEMPERATURE.................75-89.
* 24 HR TREND..................5 DEGREES WARMER.
* MIN HUMIDITY....................10-17 PCT.
* 24 HR TREND..................8 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..SOUTHEAST 5 TO 10 MPH IN THE
MORNING BECOMING SOUTHWEST 5 TO 15 MPH IN THE AFTERNOON.
* WINDS...10000 FT MSL............SOUTHWEST 10 TO 20 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
EXTENDED
WEDNESDAY
PARTLY CLOUDY. LOWS 49-64. HIGHS 77-91. SOUTHWEST
WINDS 10 TO 20 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN
15 PERCENT.
THURSDAY
CLEAR. LOWS 49-65. HIGHS 78-93. WEST WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
FRIDAY
CLEAR. LOWS 49-66. HIGHS 80-94. SOUTHWEST WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
SATURDAY
CLEAR. LOWS 50-67. HIGHS 81-95.
SUNDAY
MOSTLY CLEAR. LOWS 51-68. HIGHS 82-97.
CAZ232-182230-
IMPERIAL COUNTY AND EASTERN RIVERSIDE COUNTY-
326 AM PDT MON MAY 18 2026
TODAY
* SKY/WEATHER.....................SUNNY. PATCHY BLOWING DUST IN THE
MORNING.
* MAX TEMPERATURE.................78-87.
* 24 HR TREND..................6 DEGREES COOLER.
* MIN HUMIDITY....................6-11 PCT.
* 24 HR TREND..................11 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 10 TO 20 MPH.
* WINDS...10000 FT MSL............WEST 15 TO 25 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TONIGHT
* SKY/WEATHER.....................CLEAR.
* MIN TEMPERATURE.................59-66.
* 24 HR TREND..................LITTLE CHANGE.
* MAX HUMIDITY....................12-37 PCT.
* 24 HR TREND..................24 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTHWEST 5 TO 15 MPH.
* WINDS...10000 FT MSL............NORTHWEST 5 TO 15 MPH IN THE
EVENING BECOMING LIGHT AND VARIABLE AFTER MIDNIGHT.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TUESDAY
* SKY/WEATHER.....................MOSTLY SUNNY.
* MAX TEMPERATURE.................84-93.
* 24 HR TREND..................6 DEGREES WARMER.
* MIN HUMIDITY....................5-10 PCT.
* 24 HR TREND..................LITTLE RH CHANGE.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 5 TO 15 MPH.
* WINDS...10000 FT MSL............NORTHEAST 5 TO 15 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
EXTENDED
WEDNESDAY
CLEAR. LOWS 61-70. HIGHS 89-97. NORTHWEST WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
THURSDAY
CLEAR. LOWS 63-71. HIGHS 90-99. SOUTH WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
FRIDAY
CLEAR. LOWS 64-71. HIGHS 91-99. SOUTH WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
SATURDAY
CLEAR. LOWS 64-71. HIGHS 90-99.
SUNDAY
CLEAR. LOWS 65-72. HIGHS 91-100.
CAZ230-182230-
JOSHUA TREE NATIONAL PARK-
326 AM PDT MON MAY 18 2026
TODAY
* SKY/WEATHER.....................SUNNY.
* MAX TEMPERATURE.................67-80.
* 24 HR TREND..................7 DEGREES COOLER.
* MIN HUMIDITY....................7-11 PCT.
* 24 HR TREND..................12 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 15 TO 25 MPH IN THE MORNING
BECOMING 5 TO 15 MPH IN THE AFTERNOON.
* WINDS...10000 FT MSL............NORTHWEST 10 TO 20 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TONIGHT
* SKY/WEATHER.....................CLEAR.
* MIN TEMPERATURE.................48-60.
* 24 HR TREND..................LITTLE CHANGE.
* MAX HUMIDITY....................14-19 PCT.
* 24 HR TREND..................30 PCT DRIER.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTHWEST 5 TO 15 MPH.
* WINDS...10000 FT MSL............NORTHWEST 5 TO 15 MPH IN THE
EVENING BECOMING LIGHT AND VARIABLE AFTER MIDNIGHT.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
TUESDAY
* SKY/WEATHER.....................SUNNY.
* MAX TEMPERATURE.................73-86.
* 24 HR TREND..................6 DEGREES WARMER.
* MIN HUMIDITY....................6-10 PCT.
* 24 HR TREND..................LITTLE RH CHANGE.
* WINDS - 20 FOOT...SLOPE/VALLEY..NORTH 5 TO 15 MPH.
* WINDS...10000 FT MSL............NORTHEAST 5 TO 15 MPH.
* CHANCE OF PRECIP................0 PERCENT.
* CWR (>= 0.10 IN)................0 PERCENT.
* CHANCE OF THUNDER...............0 PERCENT.
EXTENDED
WEDNESDAY
CLEAR. LOWS 53-66. HIGHS 78-91. NORTHWEST WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
THURSDAY
CLEAR. LOWS 56-67. HIGHS 81-94. SOUTHWEST WINDS 5 TO
15 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
FRIDAY
CLEAR. LOWS 57-67. HIGHS 82-94. SOUTHWEST WINDS 10 TO
20 MPH. MINIMUM RELATIVE HUMIDITY MAY BE LOWER THAN 15 PERCENT.
SATURDAY
CLEAR. LOWS 56-68. HIGHS 81-94.
SUNDAY
CLEAR. LOWS 56-69. HIGHS 82-95.
8 TO 10 DAY OUTLOOK
MONDAY MAY 25TH THROUGH WEDNESDAY MAY 27TH:
ABOVE NORMAL TEMPERATURES AND NEAR TO ABOVE MEDIAN PRECIPITATION.
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