Alert archive / Arizona / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 35, NWS Tucson, AZ
NWS Tucson, AZ issued this severe thunderstorm warning at Jul 20, 2009, 6:29 PM MST for Pima County, Arizona. It was in force for 46 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2009, 6:29 PM MST (01:29 UTC)
- Expired
- Jul 20, 2009, 7:15 PM MST
- In force
- 46 min
- Issued by
- NWS Tucson, AZ
- Area
- Storm-based polygon
County Pima County, AZ
The radar
The Tucson radar (KEMX), 96 km from the middle of the area, began a volume at 01:32 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The nearest sounding before it
Tuscon, AZ (KTUS), launched 00:00Z, 1.5 hours before the alert went out and 71 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 14 J/kg
- Mixed-layer CIN
- -89 J/kg
- Mixed-layer LCL
- 2949 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- 9 m²/s²
- 0-3 km storm-relative helicity
- 39 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS55 KTWC 210129 SVRTWC AZC019-210215- /O.NEW.KTWC.SV.W.0035.090721T0129Z-090721T0215Z/ BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TUCSON AZ 629 PM MST MON JUL 20 2009 THE NATIONAL WEATHER SERVICE IN TUCSON HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... CENTRAL PIMA COUNTY IN SOUTH CENTRAL ARIZONA... * UNTIL 715 PM MST * AT 628 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED 6 MILES NORTHWEST OF KITT PEAK...OR 13 MILES NORTHEAST OF SELLS...AND MOVING SOUTHEAST AT 10 MPH. * OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PAN TAK. PRECAUTIONARY/PREPAREDNESS ACTIONS... EXPECT DAMAGING WINDS IN EXCESS OF 60 MPH...LARGE HAIL...FREQUENT LIGHTNING...AND HEAVY RAIN WITH THIS STORM. && LAT...LON 3197 11139 3172 11149 3214 11204 3230 11186 TIME...MOT...LOC 0129Z 309DEG 8KT 3201 11168 $$
2 follow-up statements
000 WWUS55 KTWC 210145 SVSTWC SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE TUCSON AZ 645 PM MST MON JUL 20 2009 AZC019-210215- /O.CON.KTWC.SV.W.0035.000000T0000Z-090721T0215Z/ PIMA AZ- 645 PM MST MON JUL 20 2009 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 715 PM MST FOR CENTRAL PIMA COUNTY... AT 641 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED OVER STATE HIGHWAY 86 NEAR SAN ISIDRO...OR 14 MILES EAST OF SELLS...MOVING SOUTHEAST AT 10 MPH. OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO PAN TAK AND KITT PEAK...STATE HIGHWAY 86 BETWEEN SELLS AND THREE POINTS. PRECAUTIONARY/PREPAREDNESS ACTIONS... THIS IS A DANGEROUS STORM. IF YOU ARE DRIVING ON STATE HIGHWAY 86 BETWEEN SELLS AND THREE POINTS BE PREPARED FOR DAMAGING WINDS...REDUCED VISIBILITIES BELOW 1 MILE IN VERY HEAVY DOWNPOURS...AND PONDING OF WATER ON THE HIGHWAY. && LAT...LON 3197 11139 3172 11149 3214 11204 3230 11186 TIME...MOT...LOC 0142Z 309DEG 8KT 3199 11165 $$
000 WWUS55 KTWC 210210 SVSTWC SEVERE WEATHER STATEMENT NATIONAL WEATHER SERVICE TUCSON AZ 710 PM MST MON JUL 20 2009 AZC019-210217- /O.EXP.KTWC.SV.W.0035.000000T0000Z-090721T0215Z/ PIMA AZ- 710 PM MST MON JUL 20 2009 ...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL PIMA COUNTY WILL EXPIRE AT 715 PM MST... STORMS CONTINUED ACROSS PARTS OF THE TOHONO OODHAM NATION BETWEEN SELLS AND THREE POINTS. THE THREAT OF DAMAGING WINDS HAD DIMINISHED...SO THE WARNING WILL EXPIRE AT 715 PM MST. HOWEVER...HEAVY RAINFALL ASSOCIATED WITH THESE STORMS WILL CONTINUE TO CAUSE RUNOFF PROBLEMS WITH PONDING OF WATER OR WATER FLOWING ACROSS STATE HIGHWAY 86. A SMALL STREAM FLOOD ADVISORY WILL REMAIN IN EFFECT UNTIL 11 PM MST FOR THIS SAME AREA. LAT...LON 3197 11139 3172 11149 3214 11204 3230 11186 TIME...MOT...LOC 0207Z 309DEG 8KT 3196 11160 $$
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Tucson, AZ wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 20, 1:06 PM MST, 5 hours 23 minutes earlier.
Area forecast discussion, Jul 20, 1:06 PM MST, 5 hours 23 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 110 PM MST MON JULY 20 2009 .SYNOPSIS...STRONG HIGH PRESSURE ALOFT WILL BRING HOT CONDITIONS TO SOUTHEAST ARIZONA THROUGH AT LEAST THE MIDDLE OF THE WEEK. MOISTURE WILL ALSO BE SUFFICIENT FOR THE DAILY CYCLE OF SCATTERED MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS. && .DISCUSSION...SOME CLOUDS ARE BEGINNING TO FORM OVER THE MOUNTAIN TOPS AND HIGHER ELEVATIONS OF SOUTHEAST ARIZONA...THOUGH SCATTERED SHOWER AND THUNDERSTORM ACTIVITY STILL LOOKING TO HOLD OFF. LOOKING OUTSIDE THE CWA...ACTIVITY HAS STARTED IN EARNEST ALONG THE RIM. GIVEN WEAK FLOW SEEN IN THE 12Z SOUNDING...NOT CONFIDENT THAT MUCH OF THAT WILL MAKE ITS WAY DOWN HERE. WILL LIKELY NEED TO WAIT FOR HOMEGROWN STORMS. STARTING TO SEE JUST A SMALL HANDFUL OF THOSE AT THE TIME OF THIS WRITING...MAINLY ALONG THE INTERNATIONAL BORDER AND ONE ISOLATED CELL OVER CENTRAL PIMA COUNTY. DEWPOINTS HAVE FALLEN TO THE UPPER 40S AND THAT DRYING WILL HELP IN THE FORMATION OF GUSTY WINDS/DOWNBURSTS FROM ANY STORMS THAT MAY DEVELOP TODAY. NOT MUCH CHANGE IN THINKING WITH REGARDS TO FORECAST...SO FOR DETAILS...PLEASE SEE PREV DISCUSSION SECTION BELOW. && .AVIATION...EXPECT ISOLATED TO SCATTERED TSRA/SHRA THE REST OF THIS AFTERNOON AND EVENING. THE STRONGEST TSRA WILL BE ACCOMPANIED WITH WIND GUSTS OF 40-45 KTS. OTHERWISE...SCATTERED TO OCCASIONALLY BROKEN CUMULOFORM CLOUDS WITH BASES 11-13K FT AGL INTO THIS EVENING. TSRA/ SHRA TO DECREASE IN COVERAGE AFTER 04Z AND ANY CONVECTIVE CLOUD DEBRIS TO DISSIPATE DURING THE NIGHT. SURFACE WINDS WLY/NWLY 5-15 KTS THRU 06Z THEN SLY/SELY 5-15 KTS LATE TONIGHT AND INTO TUESDAY MORNING. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...ISOLATED TO SCATTERED THUNDERSTORMS WILL OCCUR THIS WEEK...WITH THE BULK OF ACTIVITY DURING THE AFTERNOON AND EARLY NIGHTTIME HOURS. GENERALLY LIGHT DIURNALLY DRIVEN SURFACE WINDS EXCEPT STRONG AND ERRATIC WINDS NEAR THE STRONGEST THUNDERSTORMS. ABOVE NORMAL DAYTIME TEMPERATURES TO OCCUR THIS WEEK. && .PREV DISCUSSION...SOME DEBRIS CLOUDINESS TO START THE MORNING...WHICH LOOKS MORE IMPRESSIVE ON SATELLITE THAN IT DOES OUT THE WINDOW. TRENDS HAVE IT THINNING...SO THAT IS NOT EXPECTED TO INTERFERE WITH DEVELOPMENT TODAY. MORE ON THAT LATER. DEWPOINTS AT AREA ASOS STATIONS WERE MOSTLY IN THE MID 50S...WITH THE EXCEPTION OF KDUG JUST SHY OF 50. TAKING A LOOK AT THE 12Z SOUNDING...A LITTLE MORE WET BUT SLIGHTLY MORE STABLE THAN 24 HOURS AGO WITH BETTER DIRECTIONAL SHEER...THOUGH STILL FAIRLY WEAK FLOW. ALSO OF NOTE ON THE SATELLITE...ALREADY GETTING SOME ACTIVITY SOUTH OF THE BORDER...WAY SOUTH...AS WELL AS SOME LINGERING ACTIVITY SOUTHEAST OF PRESCOTT. TAKING WHAT IS ALREADY HAPPENING INTO ACCOUNT...12Z NAM SHOWS A COUPLE OF DISTURBANCES THAT WILL IMPACT SE AZ TODAY...ONE OVER SOUTHERN NV AT THIS TIME MOVING INTO NORTHERN AZ...THE OTHER PUSHING INTO SE AZ FROM THE SOUTH. SHOULD THIS HOLD...AND THE AFOREMENTIONED ACTIVITY HINTS STRONGLY IN FAVOR OF THIS...SHOULD SEE A SIMILAR DAY TODAY AS WHAT WAS SEEN YESTERDAY...WITH ACTIVITY FLARING UP BOTH ON THE RIM AND ALONG THE INTERNATIONAL BORDER...EACH SPREADING INTO SE AZ. WITH THE WEAK FLOW...NOT EXPECTING ANY STORMS THAT DEVELOP TO MOVE ALL THAT FAST. MORE MOISTURE AT THE SURFACE...SHOULD IT HOLD...MAY HELP MITIGATE A WIND THREAT FROM STORMS THAT DEVELOP...BUT GIVEN THAT THERE IS NOT MUCH DIFFERENCE IN CONDITIONS VERSUS 24 HOURS AGO...DO NOT FEEL COMFORTABLE RULING THAT OUT AT THIS TIME. MOVING OUT OF THE VERY SHORT TERM...THE HIGH WOBBLES WESTWARD AND THIS WOBBLING WILL MAKE TUES AND WEDS LOOK SIMILAR TO TODAY ACCORDING TO THE MODELS. MOVING BEYOND MID WEEK...MID TO LONG RANGE MODELS SHOW THE RIDGE INTENSIFYING WITH THE HIGH CENTER NORTH OF THE FOUR CORNERS. THIS WOULD TAKE IT OUT OF THE PRIME REAL ESTATE FOR BRINGING MOISTURE INTO SE AZ WHICH WOULD VALIDATE THE INHERITED LOW RANGE MONSOON POPS. WILL WAIT AND SEE WHAT THE 12Z RUN OFFERS...BUT CAN SEE NO REASON TO ARGUE. ONE LAST THING TO MENTION...WITH THE RIDGE REMAINING IN PLACE...AND EVEN INTENSIFYING...AFTERNOON HIGH TEMPERATURES ARE EXPECTED TO REMAIN ABOVE CLIMATOLOGICAL NORMALS AND SHOW LITTLE VARIANCE FROM DAY TO DAY. THIS WOULD KEEP THE TUCSON METRO OVER THE CENTURY MARK FOR THE ENTIRE FORECAST PERIOD...PUSHING THE WESTERN DESERTS TO CLOSER TO 110 AND EASTERN VALLEYS TO THE UPPER 90S. INHERITED FORECAST APPEARS TO BE ON TRACK. EXPECT TO MAKE SOME SLIGHT TWEAKS TO TAKE INTO ACCOUNT CURRENT OBS AND NEWEST MODEL DATA...BUT OTHERWISE NO SIGNIFICANT CHANGES EXPECTED. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. WEATHER.GOV/TUCSON
Hazardous weather outlook, Jul 20, 8:57 AM MST, 9 hours 32 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 857 AM MST MON JUL 20 2009 AZZ019-030-034-035-211200- NORTHERN GREENLEE COUNTY-UPPER GILA RIVER VALLEY- SANTA CRUZ COUNTY-COCHISE COUNTY- 857 AM MST MON JUL 20 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND CONTINUE INTO THIS EVENING. THE STRONGEST STORMS MAY PRODUCE BRIEF HEAVY RAIN AND WIND GUSTS UP TO 45 MPH. THE BULK OF THE ACTIVITY IS FORECAST TO END BY AROUND MIDNIGHT TONIGHT. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THE DAILY CYCLE OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS IS EXPECTED TO CONTINUE THROUGH SUNDAY...WITH ACTIVITY EXPECTED TO DEVELOP DURING THE AFTERNOON AND CONTINUE INTO THE EVENING HOURS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ029-031>033-211200- SOUTHEAST PINAL COUNTY-WESTERN PIMA COUNTY-TOHONO OODHAM NATION- TUCSON METRO/MARANA/GREEN VALLEY- 857 AM MST MON JUL 20 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL ARIZONA AND SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE AREA THIS AFTERNOON INTO THIS EVENING. THE STRONGEST STORMS MAY PRODUCE BRIEF PERIODS OF HEAVY RAIN...WIND GUSTS UP TO 45 MPH AND REDUCED VISIBILITIES DUE TO BLOWING DUST. THE MAJORITY OF ACTIVITY IS EXPECTED TO END BY MIDNIGHT TONIGHT. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THE DAILY CYCLE OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS IS EXPECTED TO CONTINUE THROUGH WEDNESDAY BEFORE BECOMING MORE ISOLATED FOR THE REMAINDER OF THE WEEK. ACTIVITY IS EXPECTED TO DEVELOP DURING THE AFTERNOON AND CONTINUE INTO THE EVENING HOURS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. WEATHER.GOV/TUCSON
In the hours before
Local storm report, Jul 20, 5:30 PM MST, 59 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TUCSON AZ
530 PM MST MON JUL 20 2009
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0408 PM TSTM WND DMG 7 W THREE POINTS 32.07N 111.40W
07/20/2009 PIMA AZ BROADCAST MEDIA
20 POWER POLES BLOWN DOWN ON STATE HIGHWAY 86 WEST OF
THREE POINTS.
&&
JDThe office that day
Everything else NWS Tucson, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 5:19 PM MST | Severe Thunderstorm Warning | TWC | Pima | 41 min |
| Jul 20, 6:56 PM MST | Areal Flood Advisory | TWC | Pima | 4 hr |
| Jul 20, 7:36 PM MST | Flash Flood Warning | TWC | Pima | 114 min |
Nearby
Severe Thunderstorm Warnings in Arizona, 2009Every severe thunderstorm warning in 2009
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.