Mr. Kratzer “Mr. K” Cannon Weather Acting Flight Commander David Craft NWS Albuquerque Aviation Products & Services Program Co-leader

 Thunderstorm Distribution &Types  Severe Weather, Dry Line Convection  Hail, Gust Fronts, Virga, Microbursts  Questions

Average Number of Thunderstorm Days Per Year

Moriarty, NM August 5, 2007 (Gerald White)

 Clusters are constantly evolving as outflows continue to trigger new cells  Multicell outflow boundaries tend to be larger and travel much farther than single cell outflows

Copyright 2000 Corey Mead NWS Tropopause Overshooting top Back-sheared anvil Flanking Line

 Severe icing & turbulence  Lightning  Microbursts  Low level wind shear  Potential for hail & tornados NWS

 THUNDERSTORMS  SUPERCELLS  HAIL  TORNADOES  GUST FRONTS & OUTLFOW BOUNDARIES  DRY-LINE CONVECTION  VIRGA & THE MICROBURST

** SEVERE ICING AND TURBULENCE IS IMPLIED FOR ALL THUNDERSTORMS**  FORMATION (LOCAL)  DRY-LINE  Usually to the eastern New Mexico through East Texas  Main severe weather producer for the area  DAY TIME HEATING  Overhead (look for towering clouds)  OROGRAPHIC  During the day, moves eastward at 10 knots  During the night moves westward at 10 knots  Daily movement ~100 miles

 HOT DRY AIR OF THE DESERT SW COLLIDES WITH THE MORE MOIST AIR OFF THE GULF  FORMS A NARROW CONVERGENCE ZONE IN WHICH AIR CAN MOVE UPWARDS OVER 100 MPH TO FORM 50,000 FT TS TOPS IN A MATTER OF MINUTES  TYPICALLY ORIENTED SW-NE SPANNING NM

 Check METAR map for:  converging winds  sharp change in dewpoints  Most common in spring & early summer  Daytime advances east, especially in the afternoon  Nighttime retreats west (usually) USATODAY.COM

 FORMED WHEN HOT MOIST AIR RISES  CAN BUILD AND COLLAPSE IN ONE LOCATION WITH LITTLE MOVEMENT  LOOK FOR TOWERING CUMULUS OR CASTELLANUS (CASTLE-LIKE FORMATIONS)  Rule Of Thumb - THUNDERSTORM CAN BE EXPECTED IN THE NEXT HRS

TIP: “Green” skies often indicate hail Mammatus clouds are often associated with a severe storms Hail shaft Anecdotal evidence suggests that large amounts of water and ice in a severe thunderstorm will scatter green light during the strong updrafts that occur in severe storms. People report the sky seems "brighter“ or “greener” during this time.

 Even small hail can accumulate & become a BIG problem Socorro, NM October 2004 Union County, NM August 2004 August 2004

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Surface winds can extend 2-5 miles out in front of the cloud feature associated with the gust front

OUTFLOW BOUNDARIES AND VISIBILITY RULE OF THUMB  IF YOU CAN’T SEE THRU THE “WALL OF DIRT”, WINDS >= 50 KTS  IF YOU CAN PARTIALLY SEE THRU THE “WALL OF DIRT” WINDS KTS WALL OF DUST CAUSED BY AN OUTFLOW BOUNDARY OUTFLOW BOUNDARY MOVES THROUGH CANNON AFB

VIRGA – rain that evaporates before reaching the ground creates a large mass of cold dense air capable of creating a microburst…the main cause of severe winds at Cannon outside of thunderstorms

CAUSED BY RAIN, VIRGA, STORM COLLAPSING  Can be VERY localized (e.g. the 22 end of the runway may hit 52 kts while the 31 is at kts)

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NWS

KHRX Z AUTO 01032G52KT 1 1/2SM HZ BKN006 BKN011 OVC120 20/03 A2990 KCVS Z 02036G48KT 3/4SM R31/5500VP6000FT BLDU SCT004 SCT120 23/04 A2990 RMK PK WND 03048/2140 KCVN Z AUTO 02036G44KT 1/2SM OVC005 23/03 A2996 RMK AO1 KCVN Z AUTO 01037G51KT KROW Z 34020G37KT 10SM CLR 30/M05 A2990 RMK AO2 PK WND 30053/2206

‘Hey Weather guy..., Is it gonna storm during my mission?’

 Typically 1-3 occur each year from Tucson to Phoenix  Strong multicell thunderstorm outflow boundary surges N from Tucson toward PHX  Crosses dusty desert & aggricultural fields  Visibility < 1/4SM from several Minutes to an hour