FXUS64 KHGX 250900 AFDHGX Area Forecast Discussion National Weather Service Houston/Galveston TX 400 AM CDT Sun Jul 25 2021 .DISCUSSION... Heat remains the main story early this Sunday morning. Galveston tied a record high minimum temperature yesterday, and the heat index rose to just shy of the threshold for a heat advisory. This morning doesn't look terribly different, with low temperatures in the upper 80s to around 80 degrees on track, and more highs in the mid to upper 90s inland. Like yesterday, we do look to get just enough mixing of some drier air to keep the maximum heat index just below that heat advisory threshold once again today. Of course, from a human standpoint, things are a whole lot fuzzier around these lines we're forced to draw. A heat index of 107 isn't really a whole lot different from a heat index of 108, so heat safety still needs to be a consideration for outdoor plans even without an advisory to go with it. This is surely a surprise to nobody here - it's Southeast Texas, it's summer, and even if it's not abnormally hot it can still be dangerous. The silver lining is that hopefully just the reminder that we're in a hot pattern will be all that area folks need to sidestep any potential heat threats. .SHORT TERM [Tonight Through Monday Night]... Fair weather conditions continue as ridge aloft and at the sfc remain in control over the region. Today will likely be a bit hotter as sfc ridging moves overhead. Highs will generally be in the mid to upper 90s. Soundings continue to suggest a very stable and dry profile, especially at mid to upper levels. In addition, Saharan dust will hang around Texas, bringing even a drier airmass. Enhanced afternoon mixing should be effective at bringing dewpoint values a few degrees down later today. This will result in heat index values between 100-106 degrees. Higher heat indices look possible along the coast, where slightly higher dewpoints will persist. Another mild night is expected with partly to mostly clear skies. A few low stratus and/or patchy fog could once again develop over the Brazos Valley/Victoria Crossroads early Monday morning. Otherwise, near to above normal temperatures are expected given 850 mb temperatures in the 20-23 C range. Lows will range from the 70s to low 80s. Similar weather pattern is expected on Monday...Dry and Hot. Highs will once again climb into the mid to upper 90s at most locations with heat indices in the triple digits. .LONG TERM [Tuesday Through Sunday]... After six nights, it's getting difficult to come up with new ways to say that the forecast does not significantly differ from climo, nor the the NBM means. This forecast could really just be an alternate definition in the dictionary for "summer". That's not to say each day won't be unique - the guidance is still pretty clear that a number of subtle shortwave troughs will be moving across the region on the southern fringe of a midlevel ridge centered to our northwest. The main issue here is that forecasting the fine details that will make the key difference just isn't something that can be reliably done this far out. What will the midlevel heights be precisely? Will we be on the cyclonic or anticyclonic side of the shortwaves at peak heating? I can sure take a stab at these things - and this forecast is my best shot at it. One thing I am more confident in is broader trends. With an inverted trough looking to be down around Brownsville on Tuesday, and a stream of shortwaves through the week, it seems very reasonable to expect that the dry weekend we're seeing will give way to a situation where we'll see the development of some scattered afternoon showers and storms each day from Tuesday on. Most everyone will have at least some shot for some rain each day, but as usual the best potential will be near the seabreeze boundary, which naturally becomes a source of low level convergence that can spark new storms. For what it's worth, after all that talk about the futility in trying to get too precise in this portion of the forecast, there does seem some consensus in that Wednesday will slightly favor some weak shortwave ridging, and so I do knock PoPs down a little bit (think closer to 30 rather than 40) Wednesday afternoon. Time will tell if this was wise or not. As far as temperatures go, my main trend is to slightly back off on high temps in the mid-week. With ridging centered more up in the Central Plains rather than over Texas, and with potential for some more cloudiness and some rain here and there, I'd expect lower to middle 90s to reign more than the upper 90s. Now...the NBM disagrees with me here and my highs are closer to the 25th percentile in its temperature distribution than it is to the mean or median. I will say, if the expectation of the scattered afternoon storms doesn't really come to fruition, highs will certainly go up as well. Speaking of...with the ridge looking to drift back towards the Southern Plains this weekend, my expectations would be for next weekend to look a good bit like this weekend, and the forecast reflects it with highs heading back to the upper 90s away from the coast. Given the uncertainty in a 7-8 day forecast, I haven't erased PoPs entirely, but I wouldn't be surprised to see those trend down even further than I've taken them. && .AVIATION [06Z TAF Issuance]... VFR. SKC across the area with strong capping in place. Some patchy MVFR/IFR CIGS will be possible after 09z from around CLL to UTS lasting until 13z. After that expect FEW025 rising to FEW030-070 during the late morning hours through the afternoon. && .MARINE... With high pressure overhead, light to moderate south to southwest wind will persist through the first half of the week. Rain chances will slowly increase deeper into the new week, but drier weather is expected once again for next weekend. With the generally light winds, expect quiet seas of up to two feet most of the time. When winds are at the strongest, three foot seas may build for brief periods before subsiding again when winds become lighter. && .PRELIMINARY POINT TEMPS/POPS... College Station (CLL) 97 74 97 75 97 / 0 0 0 0 20 Houston (IAH) 98 76 98 77 98 / 0 0 10 10 40 Galveston (GLS) 92 81 91 83 91 / 0 0 10 10 30 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...None. GM...None. && $$ DISCUSSION...Luchs SHORT TERM...05 LONG TERM...Luchs AVIATION...45 MARINE...Luchs