243 FXUS64 KHGX 152010 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 310 PM CDT Thu Oct 15 2020 .SHORT TERM...(Tonight through Friday Night) At 2 PM, a cold front extended from about Texarkana to Waco to around Kerrville. The front will continue to trek southward this evening and should cross the College Station area around 00z. PW values perk up to around 1.40 inches so it would be reasonable to see an expanding line of showers as the front nears the northern zones this evening. The cold front should reach the Houston area around 04z or so. PW values become more robust with values between 1.60 and 1.80 inches. Fcst soundings show a saturated layer between 950 and 700 mb and enough instability to warrant mentioning some isolated thunderstorms. The front should reach the coast between 09-11z with showers eventually reaching the coastal plain. The 850 mb front will foster additional shra/tsra between 09-13z as this feature slowly crosses the area. Winds will pick up in the wake of the front and a short fused Wind Advisory may be required for the immediate coastal zones on Friday morning. Residual precip should end by 15z with skies gradually clearing through the early afternoon. Cold air advection coupled with morning cloud cover and mixing from winds should limit the warm up and MaxT values on Friday will likely stay in the lower 70's. Skies will clear Friday night and winds relax (but don't fully decouple) so MinT values will be cool but not cold. 43 && .LONG TERM [Saturday through Thursday Night]... Return flow from the departing surface high pressure sets up Saturday, bringing near seasonal temperatures Saturday and Sunday. Lingering moisture in the 925:850 mb layer persists on Saturday, mainly across our southwestern counties. This will result in some cloud cover and perhaps sprinkles before a drier airmass filters in. 850 hPa temperatures slightly increase into the 12 to 15C range; thus, highs will be a few degrees warmer than Friday, from the upper 70s to low 80s. The good news is that it will feel comfortable thanks to surface dew points mainly in the 60s. Pressure gradient tightens and begins to fall across the southern Plains Sunday into Monday as a surface low develops in the lee of the Rockies. This will keep our region under the warm sector with reinforced surge of moisture and warm southerly flow. The associated front looks to fade away before reaching our region. However, cloud cover will gradually increase from the northwest as theta-e increases and an axis of PWATS from 1.5 - 1.8 inches moves through. Given that, have included slight chances of rain/storm Sunday night into Monday south of I-10, and elsewhere during the peak of the daytime heating, Monday afternoon. Breezy conditions are possible, mainly over the aforementioned regions with less cloud cover. Rain and storm chances increase throughout the week as different impulses bring some mid-level disturbances and weak frontal boundaries across the region. The combination of mid-to upper level forcing, daytime heating and onshore flow will bring isolated/scattered showers and storms mainly in the afternoon Tue through Thu. 05 && .MARINE... A cold front will cross the coastal waters late tonight and an offshore will develop between 09-12z. The colder air flowing over the warmer shelf waters will allow winds to increase quickly and likely exceed 20 knots by sunrise. Sustained winds should reach 25 knots with gusts possibly reaching 35 knots by mid morning. Surface high pressure will build into the southern plains so the combination of a pressure and thermal gradient will maintain strong winds over the coastal waters for much of Friday. A Small Craft Advisory has been issued for all waters for late tonight into Friday. Went well above WNA and SWAN guidance for seas on Friday as such strong winds should be capable of produce sea heights in excess of 4 feet as suggested by models. Blended the SWAN/WNA and added 2 feet. Winds should gradually relax as the surface high moves east late Friday. An east wind will develop on Saturday as the surface high moves toward the mid south. Low pressure will develop in the Texas panhandle Saturday night and a SE flow will develop and strengthen as the low deepens. The low will move east and gradually weaken on Sunday night and the attendant cold front stalls over Central Texas. The onshore flow will persist but gradually weaken Sunday night. With lower pressures over West Texas, onshore winds are expected to persist through the end of next week. 43 && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 89 58 73 52 79 / 20 40 20 0 0 Houston (IAH) 90 59 71 56 79 / 10 70 50 0 0 Galveston (GLS) 85 64 73 67 80 / 0 50 40 0 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...Small Craft Advisory from 3 AM to 1 PM CDT Friday for the following zones: Galveston Bay...Matagorda Bay. Small Craft Advisory from 3 AM to 4 PM CDT Friday for the following zones: Coastal waters from Freeport to Matagorda Ship Channel TX out 20 NM...Coastal waters from High Island to Freeport TX out 20 NM. Small Craft Advisory from 3 AM to 7 PM CDT Friday for the following zones: Waters from Freeport to Matagorda Ship Channel TX from 20 to 60 NM...Waters from High Island to Freeport TX from 20 to 60 NM. && $$