Month: June 2020

Good afternoon. We’re continuing to monitor the threat of heavy rainfall during the overnight hours as a front sags into the Houston area, and stalls. And at this point, we believe this threat warrants a Stage 1 alert on the Space City Weather Flood Scale. However, we’re following the situation closely, and it may require an upgrade to Stage 2 this evening.

In anticipation of this threat, the National Weather Service has issued a flash flood watch for the entire metro Houston area, in effect from 7 p.m. tonight through 7 a.m. Wednesday morning. In terms of overall accumulations, they are forecasting widespread totals of two to four inches of rain through tomorrow morning, with isolated areas of six to eight inches possible. This is reasonable. However, these kinds of potentially heavy rainfall events, with a slow-moving system and very high levels of atmospheric moisture, are notoriously hard to predict.

At this time we do not have much confidence in where the rains will be heaviest—it could be anywhere from south of the city to the northeast. The good news is that we expect the storms to begin to clear the area by around sunrise, or shortly thereafter. By then the atmosphere will probably be pretty worked over, and we think storm coverage should be less during the daytime on Wednesday.

Good morning. While we anticipated widespread rainfall on Monday, the intensity of the storms that developed over central Houston—in one area near downtown rainfall rates briefly exceeded a rate of 4 inches per hour—was not expected. Overall it’s a good reminder of the potential of heavy rainfall from the kinds of moist air we can see during summertime along the Gulf Coast. The potential for heavy rainfall will continue through Thursday, after which it should slacken some due to the arrival of Saharan dust.

Tuesday

We have all of the ingredients needed for heavy rainfall today, but we think storms will develop a little bit later in the day than on Monday. The first thing we’re watching is a complex of thunderstorms currently near the I-35 corridor that will move east into the Houston region later today. We expect this to weaken. Later this morning, showers should develop offshore, and move inland. And finally, tonight, a weak front will sag into Houston. Sadly this won’t bring any cooling, but it will serve as a focus for additional storm development.

Some models show this front moving slowly, and then hanging up along the coast. This could lead to a scenario where coastal counties pick up a fair amount of rain tonight and into Wednesday morning. Widespread rain totals for today and tonight will probably be about 1 to 3 inches for most of the area, but some isolated areas—most likely between Interstate 69 and the coast—may pick up as much as 5 additional inches of rain.

Wednesday

After whatever mess of storms that develops overnight weakens or moves off by around sunrise on Wednesday, it is possible that any new development later in the day will be more scattered in nature due to a worked-over atmosphere. Mostly cloudy skies should continue to keep temperatures in the upper 80s.

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Good morning. After rather boring weather last week, there are two significant weather issues to track this week. First up, as experienced by some parts of the city of Saturday and Sunday, is the potential for moderate to heavy rainfall due to moist air moving in from the Gulf of Mexico. Those rain chances should decline significantly by this weekend as Saharan dust—likely more intense than previous events of this nature—moves into the region.

Monday

The absence of high pressure and influx of moist Gulf of Mexico air will continue today. Like on Sunday, we should see the development of showers near the coast this morning. During the afternoon, these showers and thunderstorms will move inland and should spread out over much of the Houston area.

Most parts of the region that see rain will likely pick up less than one-half inch, but as we saw on Sunday, these storms have the potential to put down 2 to 3 inches of rain pretty quickly over small areas. Storms should weaken, if not go away entirely, as the sun sets. Clouds should help limit temperatures to around 90 degrees. Winds will be about 10 mph from the south, except inside storms when gusts could be substantially stronger.

Tuesday and Wednesday

Our wet and gray weather continues. This time, as moist air continues to stream inland, a storm system will move into Houston from west to east, likely reaching Houston during the afternoon or evening hours. This should enhance storm coverage, and we can expect around a 70 percent chance of rain on Tuesday and Wednesday as a result. On average, the city of Houston will likely receive 1 to 2 inches of rain, in total, through Wednesday. But again, we’re more concerned about isolated, higher totals due to the moisture available. Highs may struggle to reach 90 degrees given the cloud cover.

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Over the last couple weeks, I’ve turned into a statistics machine, focused on one value: Dewpoints. Not gonna lie, it’s been fun. Anyway, here’s another one for you today: As of yesterday evening, we had amassed 132 hours of dewpoint values at or below 65°F this month. Since 1990, the most hours in the month of June that comfortable was 197 hours in 2006. So, yeah, it’s been kind of great this month, as Junes go. Of course, as Eric alluded to yesterday, we really do need some rain. And we are going to get both the return of humidity and higher end rain chances as we go through the weekend and into next week.

Today

Yesterday was the 5th consecutive day with a high of 94° in Houston. Today could well be the 6th in a row. Expect a day much like yesterday with sunshine and some passing clouds. Rain chances aren’t zero, but they’re minimal for most of us. Areas south and west of Houston stand the best chance for some slow moving downpours this afternoon.

Saturday & Sunday

Whatever is left of our dry air will work its way off to the east by tomorrow, and we should be hot and humid. Rain chances will inch up with that change, as atmospheric moisture cranks back up closer to what is normal for this time of year.

If Friday carries a 20 percent chance of a shower, Saturday and Sunday would probably carry about a 30 percent chance or even a bit higher. Any showers could be locally heavy this weekend. Look for morning lows in the 70s and afternoon highs in the low- to mid-90s on both days. With higher humidity, expect it to feel more like typical Houston summer, with heat index values back up at or above 100° each afternoon.

Monday through Wednesday

The atmosphere will pick up even more available moisture early next week, which should be enough to allow for numerous showers and thunderstorms each day. For any given location early next week, rain chances probably “only” reach 40 or 50 percent each day, but there will be a pretty good chance that most of us see at least some rain in that timeframe. Any rain could be heavy at times. It will be warm and humid with highs around 90°, give or take a couple degrees and lows in the mid- to upper-70s inland (80° or so at the coast).

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