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

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

3. Average Number of Thunderstorm Days Per Year

4. Moriarty, NM August 5, 2007 (Gerald White)

5.  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

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

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

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

10. ** 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

11.  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 150-250 NM

12.  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 www.tornadochaser.net/dryline.html

13.  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 3 - 4 HRS

15. 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.

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

17. Photo 1 Photo 2 Photo 4 Photo 3

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

19. 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 35 - 49 KTS WALL OF DUST CAUSED BY AN OUTFLOW BOUNDARY OUTFLOW BOUNDARY MOVES THROUGH CANNON AFB

20. 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

21. 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 15-20 kts)

22. Photo 1 Photo 2 Photo 3

24. NWS

27. KHRX 172115Z AUTO 01032G52KT 1 1/2SM HZ BKN006 BKN011 OVC120 20/03 A2990 KCVS 172143Z 02036G48KT 3/4SM R31/5500VP6000FT BLDU SCT004 SCT120 23/04 A2990 RMK PK WND 03048/2140 KCVN 172155Z AUTO 02036G44KT 1/2SM OVC005 23/03 A2996 RMK AO1 KCVN 172135Z AUTO 01037G51KT KROW 172251Z 34020G37KT 10SM CLR 30/M05 A2990 RMK AO2 PK WND 30053/2206

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

29.  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 http://www.youtube.com/watch?feature=player_detailpage&v=lrcVqtmugj8