Texas Spring-2015

[TheProfessor]

MCS

Sinking air won out tonight, I wonder if it will be there tomorrow.

[gboudx]

Update from jeff

Heavy Rainfall Event increasingly likely next week.

Factors, including a slow moving/stalling cool front/surface trough, deep tropical moisture from both the Pacific and Caribbean Sea, and a slow moving upper level storm system, point to a very active period of weather from late Sunday-Friday of next week.

Moisture levels greatly increase Sunday into Monday as a slow moving frontal system stalls across the region Tuesday-Thursday. Expect numerous rounds of heavy thunderstorms with excessive rainfall rates of 2-3 inches per hour or greater. Air mass will be extremely moist and capable of some really big rainfall totals in a short period of time. Threat is there for slow storm motions and cell training making the overall situation worse in the face of widespread excessive rainfall totals over the next 7 days.

Forecasted Rainfall Amounts:
Rainfall amounts Monday-Friday will likely average 4-5 inches with isolated totals of 8-10 inches possible. Current WPC rainfall forecast attached below shows a very large area of excessive rainfall over a large portion of central and SE TX. Should these rainfall totals verify over the middle Colorado River basin, significant improvement would likely occur in the long term hydrologic drought on the Highland Lakes including Lake Travis.

The highest totals will be in strong relation to cell training and this is impossible to determine much more than a few hours in advance.

There is some potential for the trough axis to morph into a closed 850mb low over central TX toward the middle of the week. Such systems in a very tropical air mass can act like a decaying tropical cyclone and take on the daily rainfall pattern of intense nocturnal rainfall events in the late evening and early morning hours near/around the low center at which time the center of any such low pressure would become critical in forecasting where the greatest rainfall would likely occur.

Hydro:
Harris County watersheds are near base flow today and will likely be near base flow at the onset of the rainfall at some point on Monday. Repeated rounds of storms will raise watershed levels over time, but the main question is how long are the breaks between rounds and does any cell training setup over Harris County. Short term rainfall rates of 2-3 inches per hour support urban street flooding and ponding and this will be possible all week.

Rivers:
Area rivers are already high from the recent rainfall especially the Brazos and Trinity and the forecasted rainfall amounts and widespread nature of the event will support significant rises on area rivers with some likely going above flood stage. Only the San Jacinto River affects Harris County however persons traveling outside of Harris County especially toward central TX should be aware of the river/flash flood threat and messaging should encourage “Turn around don’t drown” as this is the type of rainfall setup that has in the past resulted in loss of life in normally dry river bottoms in central TX and at low water crossings.

Tides:
ESE fetch has really increased overnight in response to lowering pressures over NW TX. Nearshore buoys have been running 20-25mph this morning and this has resulted in higher than expected waves along the Gulf beaches. Tides are already running about 1-1.5 feet above normal and when combined with the current lunar cycle total water levels along the Gulf beaches and in Galveston Bay are nearing 3.0 ft. Currently the Galveston North Jetty is running at 2.6ft and Morgan’s Point is 1.6ft. There has been some wave run-up on Bolivar this morning pushing water levels near the top of the beaches. For the most part tides will remain at or below the 3.0 ft mark today and Sunday. Winds will weaken as the frontal boundary approaches Monday and this should begin to slowly lower tide levels.


Forecasted Rainfall Totals (Next 7 Days):

[Brent]

Sinking air has gone poof.. woke up to thunder and lightning here.

[Brent]

10% tornado for most of N TX now:

[DonWrk]

MCS

Where did you pull this radar loop from? Thanks.

[Ntxw]

wfaa

[TheProfessor]

10% tornado for most of N TX now:

I wouldn't be surprised if they put out a moderate threat here IF the sun comes out for a while. Right now it's raining here with some very close lightning strikes.

[TheProfessor]

It does look like clouds are beginning to clear out west so that will be something to look out for.

[Ntxw]

Rich enviroment lately with underperforming tornados, I think lack of EML (cap) has been the culprit. The boiling pot of water analogy. Models are zoning in near metroplex for some very heavy rain training the next 48 hours. So far heaviest totals have been west and north. Shift east and south in coming days.

[TheProfessor]

Tornado Watch

TORNADO WATCH OUTLINE UPDATE FOR WT 150
NWS STORM PREDICTION CENTER NORMAN OK
115 PM CDT SAT MAY 9 2015

TORNADO WATCH 150 IS IN EFFECT UNTIL 900 PM CDT FOR THE
FOLLOWING LOCATIONS

TXC009-023-035-049-059-077-083-085-093-097-113-119-121-133-139-
143-147-155-181-193-197-207-217-221-223-231-237-251-253-275-277-
337-363-367-379-397-399-417-425-429-439-441-447-485-487-497-503-
100200-
/O.NEW.KWNS.TO.A.0150.150509T1815Z-150510T0200Z/

TX
. TEXAS COUNTIES INCLUDED ARE

ARCHER BAYLOR BOSQUE
BROWN CALLAHAN CLAY
COLEMAN COLLIN COMANCHE
COOKE DALLAS DELTA
DENTON EASTLAND ELLIS
ERATH FANNIN FOARD
GRAYSON HAMILTON HARDEMAN
HASKELL HILL HOOD
HOPKINS HUNT JACK
JOHNSON JONES KNOX
LAMAR MONTAGUE PALO PINTO
PARKER RAINS ROCKWALL
RUNNELS SHACKELFORD SOMERVELL
STEPHENS TARRANT TAYLOR
THROCKMORTON WICHITA WILBARGER
WISE YOUNG
$$


ATTN...WFO...OUN...FWD...SJT...

[EF-5bigj]

It looks like it's starting to clear out now.

[aggiecutter]

SPC updated Severe Weather Outlook for this afternoon and tonight. Kind of surprising that they also just put the Texarkana area under a Tornado Watch until 10:00 tonight.

[Texas Snowman]

Super cells exploding towards Abilene.

[Texas Snowman]

Huge supercell has bombed east of Abilene. Getting that look to it, some rotation on radar it seems.

[Texas Snowman]

SPC updated Severe Weather Outlook for this afternoon and tonight. Kind of surprising that they also just put the Texarkana area under a Tornado Watch until 10:00 tonight.

Wow, moderate risk over DFW.

[BrokenGlassRepublicn]

SPC updated Severe Weather Outlook for this afternoon and tonight. Kind of surprising that they also just put the Texarkana area under a Tornado Watch until 10:00 tonight.

Wow, moderate risk over DFW.

I have a bad feeling about this evening. Today just has that eerie stillness to it.

[TheProfessor]

Looks like that southern storm will stay South of the main area, but more storms continue to pop up that need to be watched.

[cheezyWXguy]

Tornado warning in Eastland County, confirmed tornado on the ground

[TheProfessor]

No storms are heading directly towards the metroplex right now, but if they do they will likely go tornadic, it's very warm and humid here.

[aggiecutter]

Tornado warning on storm about 20 miles to the west of Texarkana. Looks like it is going to move just NW of the city, unless it takes a right turn.