TD #8 upgraded to TS Hanna, takes aim at Texas

FIRST ALERT FORECAST: Thursday, July 23 - 10 p.m.

BATON ROUGE, La. (WAFB) - There is a lot of attention directed at the Gulf as we await the upgrade for Tropical Depression #8 to Tropical Storm Hanna, which officially happened as of the 10 p.m. advisory from the National Hurricane Center.

The important news for Louisiana is that TS Hanna will be a Texas problem and not a landfall concern for the Bayou State.

Tropical Depression #8
Tropical Depression #8 (Source: WAFB)

What has changed with the NHC forecasts is a slower moving storm than previously expected and that means more time for the tropical cyclone to take advantage of the warm Gulf waters. With a relatively benign atmosphere, this Gulf system could strengthen considerably before reaching the Texas coast. As of the Thursday 4 p.m. advisory, the NHC has what will almost certainly be TS Hanna striking the Lone Star State near Corpus Christi, with sustained winds of 60 mph around midday Saturday. Were the storm to move a bit more slower than forecast, it might approach hurricane strength before its Texas landfall.

For the WAFB area, impacts are expected to be fairly limited.

While rain is likely Friday, Saturday, and Sunday, none of the three days will be all-day washouts. Instead, be ready for passing bands of showers and occasional t-storms. In most cases, the rains will likely be of fairly a short duration as they roll from east to west in the large-scale circulation. Occasional brief, heavy downpours are possible, but rain-generated flooding is not a major concern. Most WAFB communities along and north of the I-10/12 corridor can except less than 2″ of rain between now and Saturday evening, with many neighborhoods across the northern half of the WAFB region getting under 1″ through the next 48 hours. Rain totals will increase towards the coast, but even most coastal communities can expect under 3″ of rain through Saturday evening.

Rainfall estimates through Saturday evening
Rainfall estimates through Saturday evening (Source: WAFB)

The National Weather Service in Slidell has posted a Coastal Flood Advisory (CFA) for the southeastern coastal parishes and areas bordering Lake Pontchartrain. That advisory is in effect until Friday evening and calls for water levels to rise 1 to 2 ft above normal tide levels. The Storm Team suspects the CFA will be extended into and through the weekend as winds are expected to remain easterly to southeasterly through Sunday. While wind speeds will be dropping Saturday and Sunday, the persistent east to southeast flow will continue to pile water along the coast and drive additional Gulf waters through the Rigolets and into Lake Pontchartrain, which will then feed Lake Maurepas. While rising lake waters will not be a huge concern, the Storm Team suggests folks along the lower reaches of the Amite, Tickfaw, Natalbany, and Tangipahoa rivers be ready for the potential of nuisance high water this weekend.

Rainfall estimates over next seven days
Rainfall estimates over next seven days (Source: WAFB)

Unfortunately, another tropical disturbance behind TS Hanna is headed our way, keeping rain likely across the WAFB region Sunday, Monday and Tuesday. In fact, the First Alert extended outlook continues with scattered to likely daily rains through all of next week and right through the following weekend. The current guidance suggests next week’s rains will match or exceed the totals expected from TS Hanna.

FutureCast (Source: WAFB)

The NHC continues to issue advisories on Tropical Storm Gonzalo, located in the central tropical Atlantic. The NHC’s 4 p.m. advisory Thursday has Gonzalo becoming a Category 1 hurricane as it approaches the Windward Islands (the southern cluster of islands in the Lesser Antilles) and then moving over the Caribbean Sea. Once there, the forecast calls for Gonzalo’s demise over open water due to hostile wind shear and the possible influence of dry air to the storm’s north. Let’s see where and what is left of Gonzalo next Monday or Tuesday.

Tropical Storm Gonzalo
Tropical Storm Gonzalo (Source: WAFB)

So get ready for a prolonged damp spell. The only good news in the outlook is that many of us may not see 90s again until late next week!

10-day forecast
10-day forecast (Source: WAFB)

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