FXUS64 KHGX 081138 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 638 AM CDT Sun Sep 8 2024 ...New AVIATION... .SHORT TERM... (Today through Monday Night) Issued at 245 AM CDT Sun Sep 8 2024 Look, I understand if you want to skip this short term portion and get right to the attention-grabbing stuff in the long term (sniffles, trying to hold back a tear), but there is still some discussion to be had about the short term, so here goes: We've got our cold front, now a stationary front, stalled out over the Gulf waters, which will contribute to continued rain chances the next couple of days over the Gulf waters. At times, there may be some bleedover of a light, brief shower onto the coast, so I have some low PoPs in place for the immediate coastal areas tomorrow. Those rain chances will gradually increase through tomorrow night as the boundary gets slowly shoved back north ahead of the low pressure center currently designated as Invest 91, in...whatever form it may be. Though it is increasingly looking like that form will be some sort of tropical cyclone. But that's for the long term to tell you about. In the meantime, the weather will be fair, and between the sun and relatively drier air in place, we should be good for widespread highs in the 80s. The driest air looks to be far inland, as sub-50 dewpoints try...and mostly, but not entirely fail...to make it into the area. Down at the coast, winds may veer enough to try...and mostly, but entirely fail...to push dewpoints back up into the upper 60s. Without a real significant change in the humidity present, we can expect another cooler night tonight. Despite that, we can expect yesterday to be a touch warmer than today, with highs largely in the upper half of the 80s across the area. Tomorrow night, though, we're beginning to look for the first changes back to a more tropical airmass. By late Monday night, 60+ degree dewpoints look to push as far inland as places like Brenham, Huntsville, and Livingston, while the coast should see dewpoints back to around or above 70 degrees. Between that and increased cloud cover holding up the temperature floor, tomorrow night looks noticeably warmer than these weekend nights - especially at the coast. And...as mentioned before, the potential for some quick showers will lift late in the night to finish up the period. Luchs && .LONG TERM... (Tuesday through Saturday) Issued at 245 AM CDT Sun Sep 8 2024 The weather Tuesday, Wednesday, and possibly Thursday will be dictated by the eventual track of a materializing area of low pressure that is currently in the Bay of Campeche. The system could very well become the next named tropical storm of the 2024 Hurricane Season (see tropical discussion) as it moves northward, potentially along the Texas Coast. However, I want to focus on the word 'potentially' in the previous sentence because there is no shortage of uncertainty regarding the system's future track. This is due in large part to the low being in its formative stages. Track uncertainty will remain high until we are able to establish a more organized and coherent system. For anyone trying to make a rainfall forecast during the Tuesday-Thursday time frame, this uncertainty is downright frustrating. The 10th and 90th percentile NBM QPF displays the vast uncertainty quite well. You could look at the 90th percentile (NBM90) as a reasonable worst case scenario. If the NBM90 verifies, rainfall totals near the coast could approach a foot, while areas as far inland as the Brazos Valley received 3-4 inches of rain. In the alternate universe that is the NBM10, much of the CWA north and west of the Houston metro doesn't receive a drop of rainfall while the coast struggles to reach an inch of QPF. The NBM90 is likely representative of low that tracks up the Texas Coast, and possibly pushes inland over southeast Texas. The NBM10 is more representative of a low that tracks much farther east, possibly tracking as far east as the central Gulf Coast. As it stands right now, neither scenario is more likely than the other. Despite the high uncertainty, wet antecedent soil conditions coupled with a high enough chance of heavy rainfall warrant the issuance of a Slight Risk (Level 2 of 4) for excessive rainfall across our southern and coastal counties on Tuesday, and for our southeastern / eastern counties on Wednesday. Areas just north of the Slight remain under a Marginal Risk (Level 1 of 4) of excessive rainfall. This is an evolving forecast. Therefore, it is important to keep up with the latest updates since there will likely be changes. Uncertainty is even higher regarding other potential impacts such as wind and coastal flooding. Therefore, I am not going to get too into the murky details regarding these impacts. However, it is fair to assume that winds will increase (at least at the coast) as the system makes its closest approach. At this time, Wednesday appears to be the day that the low will track closest to our area. That would also coincide with the best chance of higher than normal water levels at the coast. The weather looks quieter by week's end. The early outlook for Friday and Saturday features typically warm and humid conditions with a chance of scattered showers and thunderstorms. Self && .AVIATION... (12Z TAF Issuance) Issued at 636 AM CDT Sun Sep 8 2024 Main forecast concern are NE winds, becoming gusty later this morning, with those gusts reaching to around 20 kts. Those gusts should drop off this evening, with sustained winds also diminishing modestly. Extended at IAH shows winds coming back up again tomorrow, but not as strong as today. Otherwise VFR throughout, with only some transient mid-level CIGs early this morning. && .MARINE... Issued at 245 AM CDT Sun Sep 8 2024 Moderate to strong northeasterly winds and elevated seas will persist into Monday. A surge of deep tropical moisture associated with an area of low pressure currently in the Bay of Campeche will move toward the Texas coast beginning on Monday, bringing squally conditions to the northwest Gulf for a few days. Mariners should continue to monitor the forecast as a tropical depression or tropical storm could develop in the western Gulf by the middle of the week. && .TROPICAL... Issued at 245 AM CDT Sun Sep 8 2024 The National Hurricane Center is monitoring a broad area of low pressure that has materialized over the Bay of Campeche. The low will slowly drift northwestward over the next couple of days while interacting with a frontal boundary. Associated deep tropical moisture will surge northward, increasing shower and thunderstorm activity across the northwest Gulf of Mexico. Conditions are expected to become increasingly favorable for development as the system moves northward in the western Gulf of Mexico during the middle of the week. Development into a tropical depression is likely. Development into a tropical storm is possible. Please visit hurricanes.gov for more information. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 85 58 87 67 / 0 0 0 10 Houston (IAH) 86 64 88 72 / 0 0 10 20 Galveston (GLS) 84 73 84 76 / 0 10 20 50 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...High Rip Current Risk through this evening for TXZ436>439. GM...Small Craft Should Exercise Caution until 10 AM CDT this morning for GMZ330. Small Craft Advisory until 10 AM CDT this morning for GMZ335. Small Craft Advisory until 7 AM CDT Monday for GMZ350-355-370- 375. && $$ SHORT TERM...Luchs LONG TERM....Self AVIATION...Luchs MARINE...Self