Severe Thunderstorm Warning 284, NWS Fort Worth, TX

Area Forecast Discussion
National Weather Service Fort Worth TX
254 PM CDT SAT JUL 9 2016

.DISCUSSION...
A subtle, slow-moving shortwave trough axis was over southern
Oklahoma, trailing southwest back toward I-20 west of the DFW
Metroplex this afternoon. The best axis of moisture continued to
be indicated from the Red River valley into areas along and west
of I-35/35W. PWAT values between 1.5-2.0 inches were noted within
this moist axes. With the subtlety and mesoscale nature of both
the shortwave trough and an ill-defined surface boundary between
Bowie and Wichita Falls, most high-resolution models are
struggling outside of maybe the HRRR model. The HRRR model was
followed for afternoon and early evening convective trends. A
small-scale, linear storm cluster was now pushing into areas from
northern Cooke Co into northern Grayson Co, with the stronger to
brief severe storms occurring just north of Sherman-Denison areas.

It is likely these scattered thunderstorms will expand south-
southwestward on an outflow boundary into the Highway 380
corridor between Decatur and Greenville later this afternoon,
before weaken somewhat and becoming more widely scattered in
nature this evening from Jacksboro, to Dallas-Fort Worth, To
Rockwall, the east toward Kaufman/Terrell. Residual outflow
boundaries should maintain at least low convective chance through
nightfall or nightfall, with best chances occurring on the eastern
periphery of the low-mid level theta-e ridge along and E of
I-35/35E. Finally, some dry air was noted in the 800mb-500mb layer
on forecast RAP soundings. Theta-e differences on the order of
20-25 Kelvin difference are forecast, thus evaporative cooling
should play a role along with steep, sub-cloud base lapse rates
for the the threat of a locally strong to severe downburst winds
from these storms. In addition, these storms will contain
frequent lightning and heavy downpours producing localized
flooding. There is a possible isolated occurrence of small hail.
However, with freezing levels very high in July and storms low
topped, any small hail is the least of our concerns.

The subtle upper shortwave trough will drift eastward toward the
Ark-La-Tex through Sunday, before slowly moving away toward the
Lower Mississippi River Valley early this work week. I will
maintain the low chances for convection for our far east and
northeast counties late tonight through early Sunday evening,
before mid level heights and associated large-scale subsidence
increase overhead underneath a modest upper ridge building across
Texas. Have maintained a dry and seasonably hot forecast with
highs between 95-100 degrees and lows primarily between 75-80
degrees for all of next week.

Continued lee-side surface troughing to our west-northwest in
response to upper level systems moving east across the northern
and central tier states should maintain breezy south winds 10 to
20 mph. In addition, surface dew points do appear to mix more
readily next week with dry air above the boundary layer, thus
keeping heat index values relatively lower compared to last week.
Afternoon heat index values look to remain between 95-100F in the
west and 100-103F in the east. At this time, it appears heat
advisories will likely not be needed. However, if you work
outdoors or plan on spending time recreationing outdoors, should
stay hydrated and seek shade whenever the heat gets too
oppressive.

05/

&&

.AVIATION...

/ISSUED 1245 PM CDT SAT JUL 9 2016/
Main concern for this TAF period will be the potential for
thunder at Metroplex sites late this afternoon and evening. A
swath of locally higher moisture positioned northwest of the DFW
Metroplex continues to be acted upon by subtle forcing aloft which
has lead to scattered thunderstorms mostly across southern
Oklahoma Saturday morning and early afternoon. As this area
becomes increasingly unstable later this afternoon, additional
isolated thunderstorms are expected to develop. The main window
that seems most likely for convection to impact Metroplex sites
will be very late this afternoon and early evening and have
maintained a mention of VCTS from 23-03z. Otherwise, BKN high
clouds will persist through the evening with winds around 12 kts
out of the south.

For Waco, MVFR cigs seem likely once again Sunday morning as a
20-30 kt low level jet brings another surge of low stratus
northward from southern Texas and the Hill Country. Have
prevailed BKN020 for a few hours Sunday morning, but a tempo for
these conditions may suffice depending on the areal coverage.

-Stalley

&&

.PRELIMINARY POINT TEMPS/POPS...
Dallas-Ft. Worth    78  97  79  97  80 /  20  10   5   5   5
Waco                77  98  78  98  78 /  10   5   5   5   5
Paris               75  93  75  96  76 /  30  40  10   5   5
Denton              77  95  76  96  77 /  20  10   5   5   5
McKinney            77  95  77  96  77 /  30  20   5   5   5
Dallas              79  97  79  97  80 /  20  10   5   5   5
Terrell             77  95  76  96  77 /  40  20  10   5   5
Corsicana           76  96  78  97  78 /  20  10  10   5   5
Temple              76  97  77  97  78 /  10   5   5   5   5
Mineral Wells       76  98  76  97  76 /  20   5   5   5   5

&&

.FWD Watches/Warnings/Advisories...
None.
&&

/05

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
320 PM CDT SAT JUL 9 2016

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-101145-
MONTAGUE-COOKE-GRAYSON-FANNIN-LAMAR-YOUNG-JACK-WISE-DENTON-COLLIN-
HUNT-DELTA-HOPKINS-STEPHENS-PALO PINTO-PARKER-TARRANT-DALLAS-
ROCKWALL-KAUFMAN-VAN ZANDT-RAINS-EASTLAND-ERATH-HOOD-SOMERVELL-
JOHNSON-ELLIS-HENDERSON-COMANCHE-MILLS-HAMILTON-BOSQUE-HILL-NAVARRO-
FREESTONE-ANDERSON-LAMPASAS-CORYELL-BELL-MCLENNAN-FALLS-LIMESTONE-
LEON-MILAM-ROBERTSON-
320 PM CDT SAT JUL 9 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH AND CENTRAL TEXAS.

.DAY ONE...TONIGHT.
SCATTERED THUNDERSTORMS ARE POSSIBLE TODAY AND TONIGHT NORTH OF A
COMANCHE TO PALESTINE LINE. A FEW STRONG TO MARGINALLY SEVERE
STORMS ARE POSSIBLE WITH THE PRIMARY HAZARD BEING DAMAGING
DOWNBURST WINDS. IN ADDITION...HEAVY RAINFALL MAY LEAD TO
LOCALIZED FLOODING.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.
A FEW THUNDERSTORMS WILL BE POSSIBLE ON SUNDAY NORTHEAST OF A
LINE FROM GAINESVILLE TO CANTON. GUSTY WINDS AND FREQUENT
LIGHTNING WILL ACCOMPANY SOME OF THE STORMS.

OTHERWISE...HOT CONDITIONS WILL CONTINUE SUNDAY THROUGH FRIDAY
WITH HIGH TEMPERATURES IN THE MIDDLE AND UPPER 90S AND AFTERNOON
HEAT INDEX VALUES BETWEEN 100 TO 104.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

STALLEY

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FORT WORTH TX
303 PM CDT SAT JUL 09 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0301 PM     FLASH FLOOD      SHERMAN                 33.63N  96.57W
07/09/2016                   GRAYSON            TX   PUBLIC

            N. TRAVIS RD AT HWY 75 IS SHUT DOWN DUE TO FLOODING OVER
            ROADWAY.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FORT WORTH TX
336 PM CDT SAT JUL 09 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0335 PM     FLASH FLOOD      SHERMAN                 33.63N  96.57W
07/09/2016                   GRAYSON            TX   EMERGENCY MNGR

            HWY 75 NB NORTH OF CENTER STREET IS CLOSED DUE TO WATER
            OVER ROADWAY.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
336 PM CDT SAT JUL 9 2016

TXZ103-092115-
DENTON TX-
336 PM CDT SAT JUL 9 2016

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN DENTON COUNTY UNTIL 415
PM CDT...

AT 334 PM CDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORM NEAR FROM AUBREY TO SANGER...MOVING SOUTH AT 20 MPH.

PEA SIZE HAIL AND WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH THIS
LINE OF STORMS.

LOCATIONS IMPACTED INCLUDE...
FRISCO...DENTON...LEWISVILLE...FLOWER MOUND...THE COLONY...CORINTH...
HIGHLAND VILLAGE...LAKE DALLAS...SANGER...LAKE LEWISVILLE...LITTLE ELM...
PILOT POINT...ARGYLE...HICKORY CREEK...DOUBLE OAK...SHADY SHORES...AUBREY...
NORTHLAKE...KRUGERVILLE AND CROSS ROADS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

THIS STORM MAY INTENSIFY...SO CLOSELY MONITOR FOR ADDITIONAL
INFORMATION OR POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE IN
FORT WORTH.

IF ON OR NEAR LAKE RAY ROBERTS OR LAKE LEWISVILLE...GET OUT OF THE
WATER AND MOVE INDOORS OR INSIDE A VEHICLE. IF YOU CAN HEAR
THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. DO NOT BE
CAUGHT ON THE WATER IN A THUNDERSTORM.

&&

LAT...LON 3341 9684 3309 9684 3306 9725 3342 9716
TIME...MOT...LOC 2034Z 007DEG 18KT 3329 9706

05

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
407 PM CDT SAT JUL 9 2016

TXZ091-092200-
MONTAGUE TX-
407 PM CDT SAT JUL 9 2016

...SIGNIFICANT WEATHER ADVISORY FOR MONTAGUE COUNTY UNTIL 500 PM
CDT...

AT 406 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
NOCONA...MOVING SOUTH AT 10 MPH.

WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
BOWIE...NOCONA...ST. JO...STONEBURG...FORESTBURG AND SUNSET.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

FREQUENT CLOUD TO GROUND LIGHTNING IS OCCURRING WITH THIS STORM. SEEK
A SAFE SHELTER INSIDE A BUILDING OR VEHICLE.

&&

LAT...LON 3398 9763 3395 9759 3392 9760 3390 9758
      3390 9755 3392 9749 3344 9749 3344 9798
      3388 9797 3385 9787 3386 9783 3388 9782
      3388 9780 3390 9780 3390 9778 3392 9778
      3391 9776 3394 9776 3394 9773 3399 9768
TIME...MOT...LOC 2106Z 015DEG 8KT 3382 9783

STALLEY

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FORT WORTH TX
413 PM CDT SAT JUL 09 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0405 PM     TSTM WND DMG     DENTON                  33.22N  97.15W
07/09/2016                   DENTON             TX   TRAINED SPOTTER

            LARGE TREE BRANCHES DOWN AT THE INTERSECTION OF COLLINS
            RD AND CLEVELAND RD IN DENTON.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FORT WORTH TX
426 PM CDT SAT JUL 09 2016

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0423 PM     TSTM WND GST     1 NE HASLET             32.98N  97.34W
07/09/2016  M60 MPH          TARRANT            TX   ASOS

            FORT WORTH/ALLIANCE ASOS REPORTS GUST OF 51 KTS