Houston (HGX) — the National Weather Service forecast in plain English · Plaincast

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Pleasant, dry weather expected today and tonight.

Rain chances return late this weekend as a couple of upper level disturbances push into the region. Locally heavy rainfall possible Sunday.

Colder and dry Monday-Tuesday followed by a gradual warming trend during the second half of the work week.

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SE TX sits under clear skies, with light winds and dry air persisting into the overnight hours. Satellite derived estimates show that precipitable water remain at 0.4-0.6 inches, which is much below average. near the 10th percentile for this time of year. A surface high over central TX and weak mid- upper level ridging just to our west supports benign weather for today. The combination of clear skies, dry air, and light winds sets the stage for radiational cooling through early this morning. Expect lows in the 40s in the Brazos Valley region, and low 50s elsewhere. The ridge moves east across central CONUS throughout the day, leading to subsidence across the region and suppressed rain chances. Additionally, an 850mb high moves into SE TX from the west, further strengthening subsidence and keeping stable air locked in place. Temperatures remain cool at the 850mb level, making Friday's high temperatures slightly cooler (low to mid 70s). All this to say, another cool and dry day with clear skies expected today. Heading into this evening and overnight, the upper levels moisten up, thus, high level clouds begin to fill in. That dry air continues to filter in at the surface, keeping lows in the 40s near the Brazos Valley region and 50s-60s elsewhere.

On Saturday morning, a surface high anchors over the midwest. As the high strengthens, the pressure gradient across SE TX tightens, thus, breezier conditions and occasional gusty winds can be anticipated throughout the day. Onshore flow returns, and inflow from the Gulf moistens the lower levels through the afternoon and evening; PWATS return to more average levels (~1 inch). On Saturday afternoon/evening, a shortwave trough is evident at mid-upper levels, with vort maxes embedded along the trough traveling across SE TX. Thus, rain chances return starting Saturday afternoon, continuing overnight. The mid levels remain fairly dry during this time, plus the main synoptic flow remains weak ridging. This suppresses the chance for convection, and Saturdays rain should mostly consist of showers. Regardless of rain chances, Saturday will be much cloudier than previous days. This allows for cooler daytime highs.

Sunday is where things start to get interesting. Troughing over NW CONUS deepens until eventually, a "cut-off low" feature breaks away on Sunday near the TX Panhandle. The low extends down to the surface, with a front attached. Ahead of the front, the pressure gradient tightens further, allowing for an increase in winds and gusts. Warm, moist air continues to advect inland from the Gulf, bringing precipitable water back up towards the 90th percentile (1.5 inches). This places SE TX within the warm sector of this low pressure system, increasing chances for thunderstorms (though the chance for severe weather is still uncertain). Regardless, a soggy Sunday is in store; WPC has placed a Marginal Risk (level 1 of 4) over SE TX. Minor street flooding may occur, particularly where high rain rates persist for extended periods of time. The rain continues into Sunday evening, until the cold front pushes south through the region. Most likely timing from latest guidance is a frontal passage late Sunday night into early Monday morning.

Behind the front, cooler and drier air returns. Monday is shaping up to be quite a chilly day. Post-frontal N/NE winds remain elevated throughout the day Monday, and cold air advection really helps temperatures remain cool. Grab some hot chocolate because there's a decent chance that *high* temperatures stay below 60F. Latest guidance shows a ~70% chance for Monday's high temperatures to remain below 60F in the Brazos Valley region, ~50% in Houston, and ~30% near the coast. Overnight lows took to dip into the mid 40s to mid 50s across the region. Yup, I'm definitely gonna need that hot chocolate!

By Tuesday, ridging builds back into the region. A slight warming trend persists through mid week, though northeast flow helps temperatures remain mild and drier air to stick around. Highs top out in the 60s- 70s, and overnight lows in the 50s and 60s. Another round of shortwave action appears later in the work week as the ridge weakens, thus, rain chances may return by then.