AWUS01 KWNH 250722

FFGMPD

TXZ000-251300-



Mesoscale Precipitation Discussion 1211

NWS Weather Prediction Center College Park MD

321 AM EDT Sat Oct 25 2025



Areas affected...East-Central to Southeast Texas...



Concerning...Heavy rainfall...Flash flooding possible



Valid 250720Z - 251300Z



SUMMARY...Forward speed to slow slightly and allow for 2"+/hr

rates locally.  Widely scattered spots of 2-4" totals and

localized flash flooding remain possible, especially near Houston

Metroplex.



DISCUSSION...Regional RADAR mosaic depicts older initial QLCS

across eastern TX has started to slow with fractured, but still

broad updrafts, particularly in the southern edges of the line

from Leon to Henderson county, as the main forcing from shortwave

DPVA continues to become more oblique as that wave exits across

the Red River Valley into SE OK.   The upstream trailing shortwave

associated with the strong divergent pattern across the Heat of

Texas combined with strong meso-high/cold pool is propagating the

secondary squall line quickly eastward starting to align SSW to

NNE with the initial line.  Solid southeasterly surface inflow,

veers with height to 850mb becoming increasingly confluent with

strong 30kts and 30-45 degrees of directional convergence. 

Moisture is also much deeper though the Coastal Plain with Tds in

the low to mid 70s and overall PWats over 1.75". 



As the main mid-level wave exits and core of the closed low slowly

drops southward, the downstream ridging is likely to increase and

forward speeds are to slow with steering flow shifting from SW

toward SSW.  This will increase overall rainfall duration in

combination with the strength of moisture flux convergence. 

Surface temperatures off the Gulf are also into the lower to mid

80s providing further buoyancy over the next few hours.  Rates

will increase to 2"/hr and developing streamers off the Gulf,

localized maxima/transient mergers may further enhanced highly

localized tropical/deeper warm cloud processes to support focused

2.25-2.5"/hr totals.  The line will still be forward propagating

and should limit some of the duration but still support scattered

incidents of 2-4" totals while an isolated 5" not completely out

of the realm of possibility given 00z HREF probability of 20-25%

across far SE TX through 15z; though 3" probability reach 70-90%

along and downstream of the Houston Metro providing some

confidence for localized possible flash flooding incidents through

day-break. 



Gallina



...Please see www.wpc.ncep.noaa.gov for graphic product...



ATTN...WFO...FWD...HGX...LCH...SHV...



ATTN...RFC...FWR...NWC...



LAT...LON   32269484 31969414 31429380 30819371 29789401 

            29199489 28609569 28629623 29219645 29909640 

            30369634 31479614 31899590 32159556