Jump to content

Weatherdemon

Members
 View Profile  See their activity

  • Posts

    401

  • Joined

  • Last visited

 Content Type 

Posts posted by Weatherdemon

    Severe Weather May 26th- 28th 2021

    in Central/Western States

    Posted

      Public | Counties | Probabilities | Aviation | Warnings | Initial RADAR  
    WW0215 Radar
    Hazard Tornadoes EF2+ Tornadoes
    Likelihood Moderate Low
    Severe Wind 65 kt+ Wind
    High Moderate
    Severe Hail 2"+ Hail
    High Moderate

    Note:  The expiration time in the watch graphic is amended if the watch is replaced, cancelled or extended.
    Note: Click for Watch Status Reports. 
       SEL5

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Tornado Watch Number 215
   NWS Storm Prediction Center Norman OK
   1155 AM CDT Thu May 27 2021

   The NWS Storm Prediction Center has issued a

   * Tornado Watch for portions of 
     Northern and Central Oklahoma

   * Effective this Thursday morning and evening from 1155 AM until
     700 PM CDT.

   * Primary threats include...
     A couple tornadoes possible
     Scattered damaging winds and isolated significant gusts to 80
       mph likely
     Scattered large hail and isolated very large hail events to 3
       inches in diameter likely

   SUMMARY...Thunderstorms will develop and intensify through the
   afternoon across the watch area, with supercells possible.  Very
   large hail and damaging winds are the main threat, but there is some
   concern for a few tornadoes in the most intense cells.

   The tornado watch area is approximately along and 65 statute miles
   north and south of a line from 50 miles west northwest of Clinton OK
   to 20 miles south southeast of Fayetteville AR. For a complete
   depiction of the watch see the associated watch outline update
   (WOUS64 KWNS WOU5).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Tornado Watch means conditions are favorable for
   tornadoes and severe thunderstorms in and close to the watch
   area. Persons in these areas should be on the lookout for
   threatening weather conditions and listen for later statements
   and possible warnings.

    Severe Weather May 26th- 28th 2021

    in Central/Western States

    Posted

    MD 764 graphic 
       Mesoscale Discussion 0764
   NWS Storm Prediction Center Norman OK
   1129 AM CDT Thu May 27 2021

   Areas affected...eastern Texas Panhandle...Oklahoma. far southern
   Kansas and northwest Arkansas

   Concerning...Severe potential...Watch likely 

   Valid 271629Z - 271730Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Thunderstorms are expected to develop across western
   through central Oklahoma by early afternoon and gradually spread
   east. Supercells with isolated large hail will be the initial main
   threat, but isolated damaging wind and a few tornadoes are also
   possible.

   DISCUSSION...Latest objective analysis show the atmosphere to be
   moderately to strongly unstable (2500-3000 J/kg MLCAPE) across
   western through central OK supported by steep mid-level lapse rates
   above rich low-level moisture with surface dewpoints in the low 70s
   F. Latest trends in radar show a few showers developing within a
   modest warm advection regime in the pre-frontal warm sector across
   western OK. While some remnant capping may still exist, convective
   inhibition should gradually weaken as temperatures rise into the low
   80s F. Rap analysis data show a mid-level jet approaching this
   region from the west, and effective bulk shear profiles will
   gradually increase to between 40 and 50 kt through the afternoon.
   This environment should support discrete supercells as the initial
   storm mode with large to very large hail likely. While low-level
   hodographs are not particularly large with 0-1 km storm relative
   helicity between 100-150 m2/s2 isolated tornadoes cannot be ruled
   out given degree of instability and a very moist boundary layer with
   relatively low LCLS. Additional storms may develop along the cold
   front by late afternoon across southern KS into northern OK and
   these will also likely become severe.

   ..Dial/Hart.. 05/27/2021

    Severe Weather May 26th- 28th 2021

    in Central/Western States

    Posted 

    Area Forecast Discussion
National Weather Service Tulsa OK
1124 AM CDT Thu May 27 2021

.DISCUSSION...

Forecast has been updated this morning based on the latest trends
in the data. Model soundings this morning were weakening the cap
fairly quickly today, likely due to ascent from warm
advection/isentropic lift evident on 305K surface. 12Z OUN 
sounding showed very steep mid level lapse rates and large CAPE, 
with decent deep layer shear. Low level shear is still fairly 
weak. Storms are already ongoing across NE OK, evidence of 
weakening cap. More storms to develop later today as daytime 
heating continues, even with quite a bit of cloud cover, as very 
rich low level moisture is in place with low 70s dewpoints. Very 
large hail and damaging winds main threats. Tornado potential 
should be localized and focused along outflow boundaries, though 
given the time of year and the environment, the potential does 
exist for a strong tornado. Storms eventually congeal into an MCS 
and plow southeast with wider swaths of damaging wind potential 
becoming main threat. A QLCS tornado threat will exist on any 
bowing structures that surge to the east to northeast. With
multiple rounds of storms possible along and north of I40 thru
tonight, a flash flood watch has been issued.

    Severe Weather May 26th- 28th 2021

    in Central/Western States

    Posted

    https://www.spc.noaa.gov/products/md/2021/md0763.html

     

    MD 763 graphic 
       Mesoscale Discussion 0763
   NWS Storm Prediction Center Norman OK
   1104 AM CDT Thu May 27 2021

   Areas affected...portions of southeastern Kansas and northeastern
   Oklahoma across the Ozarks and into parts of southern Illinois

   Concerning...Severe potential...Watch likely 

   Valid 271604Z - 271730Z

   Probability of Watch Issuance...80 percent

   SUMMARY...A gradual increase in storm coverage/intensity -- and
   attendant severe risk -- over the next couple of hours will likely
   require WW issuance

   DISCUSSION...Latest visible satellite imagery shows
   widespread/ongoing convection and attendant cloud cover, and several
   outflow boundaries, from southeastern Kansas and Oklahoma east to
   the mid Mississippi Valley.  The ongoing convection is occurring
   south and east of a cold front extending from a low in southwestern
   Iowa, southwestward across Kansas to the Texas Panhandle.  

   Ahead of a loosely continuous, composite outflow boundary arcing
   from northwest of St. Louis westward to southwestern Missouri, and
   then into northeastern Oklahoma, some heating/destabilization is
   underway -- particularly from southern Illinois westward across the
   Ozarks.  This trend should continue, resulting in a gradual increase
   in convective coverage and intensity over the next couple of hours.

   Area VWP data indicates around 30 kt low-level south-southwesterly
   flow across the warm sector, veering to west-southwesterly at mid
   levels.  This is providing sufficient shear for organized/mixed-mode
   convection, and therefore expect severe potential -- mainly in the
   form of damaging winds and hail -- to gradually increase in concert
   with convective intensification.  As such, expect WW issuance to be
   required within the next hour.

    MO/KS/AR/OK 2020-2021 "Winter" Discussion

    in Central/Western States

    Posted

    Norman NWS scaling down...q

     

      

    Area Forecast Discussion
National Weather Service Norman OK
1059 PM CST Sat Feb 13 2021

...New AVIATION...

.SHORT TERM...
(This evening through Sunday)
Issued at 412 PM CST Sat Feb 13 2021

As discussed in the morning update, it looks like we will have
some low-level frontogenesis developing across south central and
southeast Oklahoma. The ageostrophic response to this
frontogenesis will likely enhance some lift north of this area
creating a band of snow. These are typically somewhat narrow bands
and difficult to forecast locations very precisely, but the best
signal is that this band will set up somewhere in central to
northeastern Oklahoma where it could produce a couple of inches
of snow between midnight and sunrise. The Winter Storm Warning
starts areawide at midnight, so that still covers this potential
early round of snow.

The snow associated with the main storm system will move into the
area Sunday morning near or just before sunrise Sunday morning.
In general, the model QPF is a little lower than previous
forecasts, so have adjusted the snow amounts down just a touch. We
are still expecting amounts of 5 inches or more throughout the
forecast area, with the highest amounts of roughly 8 to 9 inches
across southwest Oklahoma and area of north Texas near Wichita 
Falls. The storm system looks a little quicker and have adjusted
the timing of the forecast and heaviest snowfall a little bit.

     

×
×
  • Create New...