Jump to content
  • Member Statistics

    17,611
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

May 21st Severe Weather Obs/Discussion


andyhb

Recommended Posts

lots of open area between Waco and Temple/Killeen you could get some good shots. just don't want to go too far south of Killeen/Temple as you start to get mixed up with the folks in Austin and also Bryan/College Station/Texas A&M.

you might want to check with MSP to see if there's any construction to worry about in central TX, given that last I knew he goes to A&M.

I-35 is a real mess between Waco and the split in Hillsboro. I've driven it five times in the last ten days and hit a backup every time.

We will be obviously watching this closely here in DFW. I would be out chasing if I was not at work all day. People here at the office already discussing where to go in case of a tornado. I live on the third floor of an old apartment complex, so needless to say I'll be staying at the office if any threat is imminent. I got some great pics of mammatus clouds yesterday evening and will try to post pics today if anything interesting rumbles through.

Link to comment
Share on other sites

  • Replies 97
  • Created
  • Last Reply

TW is mod across the board for everything, but high for severe wind... disco from the watch follows:

DISCUSSION...AIDED BY FORCING ASSOCIATED WITH A SHORT WAVE IMPULSE   TURNING EAST OF THE SOUTHERN HIGH PLAINS...INCREASING THUNDERSTORM   DEVELOPMENT IS EXPECTED DURING THE NEXT FEW HOURS ALONG A SURFACE   COLD FRONT AND REMNANT OUTFLOW BOUNDARY ACROSS THE WW AREA.  THE   OUTFLOW BOUNDARY...SITUATED NEAR OR JUST SOUTH OF THE RED RIVER MAY   BECOME THE FOCUS FOR AN INCREASINGLY ORGANIZED MESOSCALE CONVECTIVE   SYSTEM CAPABLE OF PRODUCING DAMAGING WINDS...LARGE HAIL AND ISOLATED   TORNADOES.  DISCRETE SUPERCELLS ARE POSSIBLE ALONG THE TRAILING   SOUTHERN FLANK OF THE DEVELOPING SYSTEM...SOUTHWARD THROUGH CENTRAL   TEXAS BY THIS AFTERNOON...AS WELL AS AHEAD OF THE SQUALL LINE ACROSS   NORTHERN TEXAS.  ONE OR TWO STRONG TORNADOES MAY NOT BE OUT OF THE   QUESTION.
Link to comment
Share on other sites

Probability of 2 or more tornadoes

Mod (40%)

Probability of 1 or more strong (F2-F5) tornadoes

Mod (30%)

Wind

 

Probability of 10 or more severe wind events

High (80%)

Probability of 1 or more wind events > 65 knots

Mod (30%)

Hail

 

Probability of 10 or more severe hail events

Mod (50%)

Probability of 1 or more hailstones > 2 inches

Mod (30%)

Combined Severe Hail/Wind

 

Probability of 6 or more combined severe hail/wind events

High (>95%)

Link to comment
Share on other sites

Let's see if the WRF-NMM can nail an event for the third day in a row. Current surface data and PVA at 700-400 mb seem to line up with the WRF-NMM in favoring a strengthening/backing low-level wind profile in about two to three hours. I would say that the tornado threat appears to be in line with the SPC along with a tremendous wind potential affecting the DFW metroplex.

Link to comment
Share on other sites

Storm nearing witchita falls might be one to watch if it can stay ahead of the line.

That cell, and the one south of it, both look anafrontal to me and are probably elevated. You can see the outflow boundary on Dyess AFB radar, well south of the action, now pressing south through Abiliene.

Link to comment
Share on other sites

That cell, and the one south of it, both look anafrontal to me and are probably elevated. You can see the outflow boundary on Dyess AFB radar, well south of the action, now pressing south through Abiliene.

Agree. FWD already talking about this and suggesting the area to watch will be ahead of the boundary

Link to comment
Share on other sites

That cell, and the one south of it, both look anafrontal to me and are probably elevated. You can see the outflow boundary on Dyess AFB radar, well south of the action, now pressing south through Abiliene.

 

 

Agreed.  The southern one had a chance as it was right along the boundary for a while.  Now everything looks a-mess.

Link to comment
Share on other sites

I am posting the 4-hour forecast of STP (significant tornado parameter.) Valid for 20z or 3:00PM central. It is pretty high around Texarkana. This leads me to believe we will have at least 5 tornadoes in the risk area today. It may be at least 2-3 tornadoes are NOT right at this max in STP. That's just a guess based on past experience. The 0-1km shear is also pretty decent, up to 30 knots right now for southern Arkansas.

 

post-1182-0-96794600-1369155263_thumb.jp

 

 

Link to comment
Share on other sites

Update from Jeff: (Pro Met HCFCD)

 

SPC has issued a large tornado watch for much of N and portions of C TX until 700pm.

 

Outflow boundary from S OK convection is surging southward over N TX while at the same time the dry line/cold front combo is approaching from the west. The air mass over N and C TX is becoming very unstable with CAPE values of 3000-4000 J/kg along the I-35 corridor. With continued surface heating, expect supercells to develop within the next few hours from NW of Fort Worth SSW along the dry line deep into C TX. Backed low level winds near the incoming outflow boundary from the NW may help to enhance the tornado threat near/around Fort Worth over the next several hours.

 

Southern flank supercells that fire along the dry line west of Austin/Waco will have a high end tornado threat along with a very large hail threat (greater than 2.0 inches in diameter). Storms will congeal into a forward fast moving line by this evening with a very significant wind damage threat (frequent speeds to hurricane force) spreading across much of NTX into our northern  counties. Short term high resolution models continue to suggest a bow echo evolving over N TX with southern flank supercells with a tornado threat across central TX. Think the biggest tornado threat will reside NW of a line from Austin to near College Station to Lufkin and ahead of the main squall line.

 

Meso models continue to trend toward bring an MCS/bow echo into and possibly even through much of SE TX overnight. Still some questions on the cap intensity with the same models showing a building cap after sunset from deep south TX into the coastal bend so even though the meso models are wanting to bring storms all the way to the coast, the thermodynamic profile may not be very favorable south of I-10.

 

 

 

 

 

Link to comment
Share on other sites

We are dropping south prob to somewhere between Austin and San Angelo. Not sold given radar but that area seems to have the best chance of something chaseable.

Link to comment
Share on other sites

We are dropping south prob to somewhere between Austin and San Angelo. Not sold given radar but that area seems to have the best chance of something chaseable.

 

Good luck! I was considering the RR area E of 35, but the boundary seems to be racing S and posing an undercutting problem. C TX seems the best play for now. Hoping for a return to peaceful High Plains chasing come Thursday.

Link to comment
Share on other sites

Good luck! I was considering the RR area E of 35, but the boundary seems to be racing S and posing an undercutting problem. C TX seems the best play for now. Hoping for a return to peaceful High Plains chasing come Thursday.

If we weren't chasecationing today would be very tempting to sit out. Oh well. Some Caprock love on Thursday would be great. At least it's a reason to grab our steak at the Big Texan. ;)
Link to comment
Share on other sites

MESOSCALE DISCUSSION 0752
   NWS STORM PREDICTION CENTER NORMAN OK
   0119 PM CDT TUE MAY 21 2013
  
   AREAS AFFECTED...NRN TX INTO THE ARKLATEX REGION
  
   CONCERNING...TORNADO WATCH 201...
  
   VALID 211819Z - 212015Z
  
   THE SEVERE WEATHER THREAT FOR TORNADO WATCH 201 CONTINUES.
  
   SUMMARY...STORMS ARE GRADUALLY INCREASING IN COVERAGE...AND MAY
   RAPIDLY INTENSIFY CLOSE TO OR JUST E OF THE DALLAS/FT. WORTH AREA
   EWD INTO THE ARKLATEX WITH MAINLY DAMAGING WINDS AND HAIL.
  
   DISCUSSION...SURFACE ANALYSIS AND VISIBLE IMAGERY SHOW THAT A BAND
   OF THICK STRATUS CONTINUES TO HAMPER HEATING AND SURFACE BASED
   DESTABILIZATION W OF THE I-35 CORRIDOR IN TX AS OUTFLOW AND COLD
   FRONT CONTINUE TO RAPIDLY TRAVEL SEWD OVER WRN N TX.
   CURRENTLY...THESE STORMS ARE FORMING MAINLY BEHIND THE LEADING
   OUTFLOW...DUE IN PART TO THE COOLER SURFACE AIR AND MARGINAL STORM
   RELATIVE INFLOW.
  
   HOWEVER...HEATING PERSISTS ALONG AND E OF I-35...WITH TEMPERATURES
   MAINLY IN THE 82-84 F RANGE. MODIFICATION OF THE 18Z FWD SOUNDING
   SUGGESTS CAPPING IN THESE AREAS IS AT A MINIMUM...AND THAT THE
   APPROACHING LINE OF CONVECTION WILL STRENGTHEN AS IT BEGINS TO
   INGEST MORE UNSTABLE AIR. A GENERAL SWWD GROWTH ALONG THE COLD FRONT
   IS ALSO EXPECTED LATER THIS AFTERNOON TOWARD THE WACO AREA. GIVEN
   THE RAPIDLY ADVANCING GUST FRONT...AND VEERED 850 MB WINDS PRIMARILY
   PARALLEL TO THE BOUNDARY...THE TORNADO THREAT MAY NOT BE HIGH...BUT
   IF SUPERCELLS CAN FORM THEN ROTATION COULD DEVELOP ALONG ANY
   INFLECTION POINTS IN THE LINE.
  
   ELSEWHERE...AN OUTFLOW BOUNDARY CONTINUES TO SAG SWD ACROSS THE RED
   RIVER INTO NRN TX AND SWRN AR...WITH SPORADIC SMALL STORMS FORMING
   TO THE N OF IT. THESE CELLS MAY BECOME A BIT BETTER ORGANIZED AS THE
   UPPER TROUGH NEARS...AND SOME FURTHER DESTABILIZATION OCCURS
   UPSTREAM. DEEP LAYER SHEAR WILL REMAIN FAVORABLE FOR ELEVATED SEVERE
   HAIL WITH THIS ACTIVITY PRIOR TO THE MAIN LINE OF STORMS ARRIVING
   ACROSS THE RED RIVER VALLEY AND SWRN AR. ALSO...THERE IS A
   CONDITIONAL TORNADO THREAT IF CELLS CAN MATURE BEFORE THEY CROSS THE
   OUTFLOW BOUNDARY. HOWEVER...CELL MOTION WOULD CAUSE THESE STORMS TO
   LOSE TORNADO THREAT QUICKLY ONCE THEY CROSS THE FRONT.
  
   ..JEWELL.. 05/21/2013
  
  
   ATTN...WFO...SHV...TSA...FWD...OUN...EWX...SJT...
 

 

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...