Brief thunderstorms resulted in locally damaging winds in Tempe.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PSR wrote it up.
Brief thunderstorms resulted in locally damaging winds in Tempe.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Phoenix, AZ wrote its last area forecast discussion before the first event at May 19, 5:00 AM MST, 1 hour 41 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PHOENIX AZ 500 AM MST TUE MAY 19 2009 .UPDATE...UPDATED FIRE WX DISCUSSION. && .SYNOPSIS... A LOW PRESSURE SYSTEM CENTERED OFF SHORE FROM SAN DIEGO WILL SLOWLY MOVE EASTWARD THE NEXT SEVERAL DAYS LEADING TO A CHANCE OF SHOWERS AND THUNDERSTORMS OFF AND ON...MAINLY OVER SOUTH-CENTRAL ARIZONA. IN ADDITION...TEMPERATURES WILL BECOME MUCH COOLER BY WEDNESDAY WITH LITTLE CHANGE THURSDAY. A GRADUAL WARMING AND DRYING TREND WILL TAKE PLACE FROM WEST TO EAST BEGINNING FRIDAY. HIGH TEMPERATURES ARE EXPECTED TO BE A FEW DEGREES ABOVE NORMAL OVER THE WEEKEND. && .DISCUSSION... VORT MAX MOVING NORTHWARD THROUGH ARIZONA EARLY THIS MORNING EVIDENT ON WATER VAPOR IMAGERY. OVER THE NEXT FEW DAYS THERE ARE LIKELY TO BE MORE THAT WILL MOVE OVER OUR FORECAST AREA AS THE UPPER LOW CENTERED OFFSHORE SLOWLY MOVES EASTWARD. JUST WHEN AND WHERE THESE FEATURES WILL BE REMAINS TO BE SEEN. THE 00Z GFS INDICATES ONE FOR TODAY AND A MORE DISTINCT ONE ON WEDNESDAY. THE NAM IS MORE SUBTLE WITH THE WAVES AT THE UPPER LEVELS...THOUGH IT HAS A VERY DISTINCT CIRCULATION AT 500 MB MOVING IN WEDNESDAY. A BIGGER DIFFERENCE IN THE 00Z SOLUTIONS BETWEEN THE NAM AND GFS IS IN THE MOISTURE DISTRIBUTION. THE NAM IS QUITE A BIT MORE GENEROUS WITH HOW FAR WEST IT SPREADS DEEP MOISTURE...COVERING THE NORTHEASTERN THREE-QUARTERS OF ARIZONA BY LATE WEDNESDAY...WHILE THE GFS KEEPS IT MORE TO THE EASTERN QUARTER OF ARIZONA. THE NAM MAY NOT BE ALL THAT OUT OF LINE GIVEN TRENDS IN SATELLITE-DERIVED PWATER ALONG THE MEXICAN COAST. HOWEVER...SAFER BET IS TO LEAN TOWARD GFS SOLUTION IN LIGHT OF MORE ROBUST DATA INGEST AND GENERALLY SUPERIOR PERFORMANCE WITH FLOW FEATURES. DESPITE DIFFERENCES...BOTH MODELS ARE INDICATING MUCH COOLER TEMPERATURES AND MORE CLOUDINESS WEDNESDAY. THE CLOUDINESS IS APT TO REDUCE BOUNDARY LAYER INSTABILITY BUT HAVE INCREASED POPS DUE TO INCREASED MOISTURE AVAILABILITY AND GREATER LIKELIHOOD OF DYNAMICAL FORCING. HAVE ALSO INCREASED POPS FOR THURSDAY AND FRIDAY DUE TO CLOSE PROXIMITY OF THE LOW CENTER AND LINGERING MOISTURE. BEST CHANCE OF PRECIP FOR SOUTHEAST CALIFORNIA LOOKS TO BE THURSDAY AS LOW CENTER MOVES OVERHEAD. OTHERWISE...POPS THROUGH FRIDAY WILL BE LIMITED TO ARIZONA PORTION OF THE FORECAST AREA. SATURDAY THROUGH TUESDAY...BOTH GFS AND ECMWF HAVE BEEN TRENDING TOWARD A SLOWER EXIT OF THE TROUGH OVER THE DESERT SOUTHWEST. IN FACT THE 00Z ECWMF KEEPS THE TROUGH CENTERED NEAR THE AZ/UT/NV BORDER AREA THROUGH THE WEEKEND...A DEEPER SOLUTION THAN THE 12Z RUN. THE GFS IS FURTHER DOWNSTREAM WITH IT. OVERALL...A GRADUAL WARMING TREND WITH DRY CONDITIONS IS IN STORE. HOWEVER...BOTH MODELS ARE INDICATING SOUTHERN BRANCH FLOW WILL KEEP A STRONG RIDGE FROM BUILDING OVER OUR FORECAST AREA. && .AVIATION... CONFIDENCE IS RELATIVELY HIGH THAT CONVECTION WILL BE CONFINED TO CENTRAL AND EASTERN AZ TODAY. INDICATED SOME CB IN THE TAFS AT KPHX/KIWA...THOUGH THUNDERSTORM ACTIVITY REALLY LOOKS TO BE FURTHER EAST...MAINLY OVER THE HIGHER TERRAIN. FLOW WILL BE MORE SOUTHWESTERLY THIS AFTERNOON AROUND THE RIDGE OFF NORTHERN BAJA. WINDS WILL BECOME MORE COMPLEX THIS EVENING...AS OUTFLOW BOUNDARIES MOVE INTO THE VALLEY. LOOKING AHEAD...HIGHER COVERAGE OF STORMS EXPECTED WED AND THU. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... INCREASING MOISTURE WILL MEAN AN INCREASED CHANCE FOR SHOWERS AND THUNDERSTORMS WED-THU AS A LOW PRESSURE SYSTEM APPROACHES THE REGION. HIGHEST RAIN CHANCES AND RAIN TOTALS ARE EXPECTED ACROSS THE CLIMATOLOGICALLY FAVORED HIGHER TERRAIN OF SOUTH-CENTRAL AZ. DRY LIGHTNING WILL REMAIN A THREAT AS WELL...WHICH MAY ACT AS AN IGNITION TRIGGER. WARMER AND DRIER CONDITIONS ARE EXPECTED BY THE WEEKEND AS THE LOW MOVES SLOWLY EAST OF THE AREA. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT WEATHER.GOV/PHOENIX DISCUSSION...AJ AVIATION...HIRSCH FIRE WEATHER...HIRSCH
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE PHOENIX AZ 546 AM MST TUE MAY 19 2009 AZZ020>028-CAZ030>033-200100- LOWER COLORADO RIVER VALLEY AZ-WEST CENTRAL DESERTS- NORTHWEST MARICOPA COUNTY-GREATER PHOENIX AREA- SOUTHERN GILA COUNTY/TONTO NATIONAL FOREST FOOTHILLS- YUMA/MARTINEZ LAKE AND VICINITY-SOUTHWEST DESERTS- SOUTHWEST MARICOPA COUNTY-NORTHWEST AND NORTH CENTRAL PINAL COUNTY- JOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CA- RIVERSIDE COUNTY/EASTERN DESERTS-IMPERIAL COUNTY- 546 AM MST TUE MAY 19 2009 /546 AM PDT TUE MAY 19 2009/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST-CENTRAL ARIZONA...EXTREME SOUTHWEST ARIZONA...EXTREME WEST-CENTRAL ARIZONA... SOUTH-CENTRAL ARIZONA...SOUTHWEST ARIZONA...WEST-CENTRAL ARIZONA... EXTREME SOUTHEAST CALIFORNIA AND SOUTHEAST CALIFORNIA. .DAY ONE...TODAY AND TONIGHT THERE WILL BE A SLIGHT CHANCE OF THUNDERSTORMS TODAY AND TONIGHT PRIMARILY OVER ARIZONA...WITH A BETTER CHANCE OVER THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA. THE MANI HAZARD WILL BE VERY STRONG WINDS WITH POTENTIAL FOR DAMAGING STRENGTH WINDS TO OCCUR DUE TO DOWNBURSTS. ACCOMPANYING THE WINDS WILL BE AREAS OF BLOWING DUST AND THE ASSOCIATED HAZARD TO MOTORISTS. THE STRONGEST STORMS WILL BE CAPABLE OF BRIEF HEAVY RAIN OVER A VERY LOCALIZED AREA...BUT ANY STORMS THAT MANAGE TO FORM ARE NOT ANTICIPATED TO BE CAPABLE OF PRODUCING FLOODING. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THERE WILL BE A CHANCE OF THUNDERSTORMS OFF AND ON THROUGH FRIDAY...MAINLY OVER SOUTH-CENTRAL ARIZONA. THERE WILL BE POTENTIAL FOR DOWNBURSTS EACH DAY. ON WEDNESDAY AND THURSDAY...THERE WILL ALSO BE MORE OF A POSSIBILITY FOR A STORM TO PRODUCE ENOUGH RAINFALL TO POSE A LOCALIZED FLOODING HAZARD. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT WEATHER.GOV/PHOENIX AJ
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
530 AM MST TUE MAY 19 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1007 PM TSTM WND DMG 4 ENE GUADALUPE 33.38N 111.89W
05/18/2009 MARICOPA AZ TRAINED SPOTTER
TREE UPROOTED
&&
MHIRSCHPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE PHOENIX AZ
607 AM MST TUE MAY 19 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0544 AM NON-TSTM WND GST 6 W CHANDLER 33.28N 111.96W
05/19/2009 M45.00 MPH MARICOPA AZ TRAINED SPOTTER
45 MPH MEASURED GUST NEAR VIRGA/LIGHT RAIN SHOWER.
LOCATION IS ON THE OTHER SIDE OF INTERSTATE 10 FROM
FIREBIRD RACEWAY.
&&
AJThe Phoenix radar (KIWA), 28 km away, was scanning. The volume nearest the first event began at 13:39 UTC.
1 thunderstorm wind. Local standard time, as filed.
Winds damaged a small structure at a Tempe car dealership.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2009Every state in 2009This day in weather historyWarnings in Arizona, May 2009
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 169354.