Flash Flood Warning 19, NWS Billings, MT

SOUTH CENTRAL AND SOUTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BILLINGS MT
155 PM MDT WED JUL 18 2001

.THU AND FRI...
THUNDERSTORM PATTERN REMAINS IN PLACE. DEEP UPPER LOW SPINNING OVER
ALBERTA. THE LOW WAS NOT MOVING MUCH AND SENDING SHORTWAVE ENERGY AROUND
THE PERIPHERY OF IT. ONE SUCH WAVE MOVING INTO NORTHEAST MONTANA AT THE
MOMENT WITH ANOTHER CRUISING INTO EASTERN IDAHO. CU DEVELOPING OVER THE
MOUNTAINS. ATMOSPHERE DESTABILIZING WITH LI'S AROUND -4 AND CAPES AROUND
1200 JKG OVER SOUTHERN MONTANA. FLOW AT THE SURFACE PRETTY LIGHT...BUT
INCREASES UP THROUGH 600MB. STORMS SHOULD HAVE TILT AND WITH WET BULB
ZERO TEMPERATURES REMAINING LOW...HAIL A GOOD BET. THE SOUTHEAST WILL
HAVE TO OVERCOME CAPPING...BUT AS A SHORTWAVE MOVES IN THERE THIS
EVENING...THIS SHOULD BE DONE. WILL MENTION SEVERE IN THE ZONES.

MORE SHORTWAVES ROUND THE CANADIAN UPPER LOW AND SERVE TO ENHANCE THE
SOUTHWEST FLOW OVER THE STATE. NEXT WAVE PROGGED TO MOVE IN THURSDAY
AFTERNOON. ANOTHER UPSTREAM WAVE PROGGED INTO THE SOUTHWEST AROUND
MIDNIGHT THURSDAY NIGHT. THIS WAVE TRACKS INTO NORTHERN MONTANA
OVERNIGHT...SO COULD BE A NOCTURNAL EVENT. WILL LEAVE SCATTERED POPS IN.
THE SOUTHERN TAIL OF THE WAVE WILL LINGER IN THE SOUTHEAST THROUGH NOON.
WILL PROBABLY BE DRY MOST OF THE DAY FRIDAY. ANOTHER WEAK WAVE INVADES
THE SOUTHWEST FRIDAY AFTERNOON...BUT THIS WAVE IS PRETTY WEAK COMPARED
TO THE OTHER. WILL KEEP LOW SCATTERED POPS FRIDAY FOR THE MORNING
POSSIBILITY AND ALSO THE AFTERNOON WAVE AS THE ATMOSPHERE REMAINS VERY
UNSTABLE. HEIGHTS TO RISE A LITTLE FRIDAY AS THE NEXT UPPER LOW DEVELOPS
OVER WASHINGTON AND OREGON. WILL GO A LITTLE WARMER FRIDAY. HUMPHREY

.SAT...SUN...MON...TUE...WED...
THE UPPER LEVEL PATTERN WILL CONTINUE A MOIST UNSTABLE SOUTHWEST FLOW
ALOFT OVER THE NORTHERN ROCKIES INTO MONDAY AS AN UPPER TROUGH MOVES
ACROSS MONTANA. THIS KEEPS SCATTERED THUNDERSTORMS IN THE FORECAST
INTO MONDAY WHILE TEMPERATURES ARE VERY WARM. WEAK RIDGING THEN BEGINS
TO BUILD ACROSS THE AREA MONDAY THROUGH WEDNESDAY WITH TEMPERATURES
SLOWLY INCREASING WHILE CHANCES OF THUNDERSTORMS DIMINISH. THORICHT

    THU     FRI     SAT     SUN     MON     TUE     WED
-----------------------------------------------------------
BIL 056/083 058/087 060/085 060/086 060/087 057/085 058/086
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
LVM 048/081 050/084 057/084 057/087 057/087 055/084 055/084
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
HDN 054/085 056/089 059/086 059/090 059/090 058/087 056/087
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
MLS 060/088 062/091 062/089 062/090 062/090 059/088 060/089
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
4BQ 059/087 061/090 061/088 061/091 061/091 058/087 059/087
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
BHK 058/087 060/090 060/087 060/090 060/090 056/088 057/088
    44/T    43/T    33/T    33/T    32/B    22/B    22/B
SHR 052/085 054/089 058/085 058/086 058/088 056/086 056/086
    44/T    43/T    33/T    33/T    32/B    22/B    22/B

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BILLINGS, MT
400 PM MDT WED JUL 18 2001

TIME(MDT)  .....CITY LOCATION.....STATE   ...EVENT/REMARKS...
           ....COUNTY LOCATION....

0720 PM    10 SE ROUNDUP             MT   80 MPH TSTM WIND GUST
07/02/01   MUSSELSHELL                    LAW ENFORCEMENT REPORTED
                                          TREES DOWN IN THE BULL
                                          MOUNTAINS

0930 PM    DECKER                    MT   FLASH FLOODS
07/14/01   BIG HORN                       145 FEET OF ROAD BED
                                          WASHED OUT BENEATH THE
                                          BURLINGTON/NORTHERN
                                          RAILROAD TRACKS. 2 FEET OF
                                          WATER OVER TRACKS. REPORTED
                                          BY RAILROAD OFFICIAL.

0445 PM    BOYD                      MT   .75 INCH HAIL
07/17/01   CARBON                         REPORTED BY SPOTTERS

0430 PM    3 W PARK CITY             MT   .75 INCH HAIL
07/17/01   STILLWATER                     REPORTED BY SPOTTERS

0532 PM    10 W BILLINGS             MT   .75 INCH HAIL
07/17/01   YELLOWSTONE                    REPORTED BY NWS EMPLOYEE.

0545 PM    BILLINGS                  MT   FLASH FLOODS
07/17/01   YELLOWSTONE                    STREET FLOODING ON THE
                                          SOUTH SIDE OF BILLINGS.
                                          REPORTED BY NWS EMPLOYEE.

0700 PM    9.5 N HARDIN              MT   .75 INCH HAIL
07/17/01   BIG HORN                       REPORTED BY SPOTTERS

0200 AM    25 NW BAKER               MT   .75 INCH HAIL
07/18/01   FALLON                         REPORTED BY SPOTTERS

1235 AM    11 SE MILES CITY          MT   .75 INCH HAIL
07/18/01   CUSTER                         REPORTED BY SPOTTERS

1200 AM    1[0 NE MILES CITY          MT   .75 INCH HAIL
07/18/01   CUSTER                         REPORTED BY SPOTTERS

TJ