More Heavy Rain, Then A Break For Soaked Texas and Oklahoma

Weather – by Linda Lam

Yes, more heavy rain is forecast for the flood-weary southern Plains, but there is light at the end of this tunnel.

Early Friday morning a flash flood emergency was issued for portions of the Dallas metro area, where multiple water rescues are occurring and travel has become impossible in some areas. Just northeast of Dallas rainfall amounts of 4 to 6 inches have been reported from early Thursday morning to early Friday morning and it is still raining in the area.  

Flash flooding was also reported Thursday in parts of Oklahoma and Texas. A flash flood emergency was issued in Lawton, Oklahoma.

On Wednesday, mudslides were reported near Palo Duro Canyon in the Texas panhandle, evacuations were prompted in the Fort Worth suburb of Blue Mound, numerous streets were flooded in Great Bend, Kansas, and early Wednesday, another round of soaking rain descended into Houston, just 24 hours after a massive flood event brought parts of the Houston area to a halt.

Officials in parts of Texas have warned that river flooding could last for weeks as some areas have seen more than 20 inches of rain during May. Several cities have already seen their wettest May, or even month, on record.

Widespread flash flooding also occurred in Austin this past holiday weekend. Shoal Creek was just one of many creeks and rivers that came out of its banks and flooded the area Monday afternoon.

Memorial Day weekend flooding also swamped Wimberley, Texas and several locations in Oklahoma.

Through Saturday: More Rain on the Way

A southward dip in the jet stream has been locked in place over the western states, allowing it to launch disturbances into the Plains. Those disturbances provide the necessary lift in the atmosphere to trigger thunderstorm development as they intercept a warm, moist air mass in place near the surface of the earth.

Unfortunately, more widespread showers and thunderstorms are expected in the Southern Plains through Saturday as a late season cold front approaches the region. Southeastern Texas may see thunderstorms continue into Sunday.

Of most concern is the potential for slow-moving clusters of thunderstorms with locally heavy rainfall, particularly during the overnight/early morning hours, in the Plains states from parts of Kansas to Oklahoma and Texas.

Any rainfall will run off quickly because the soil is so saturated, triggering additional flash flooding. River flooding will continue on larger rivers as crests move downstream.

(INTERACTIVE MAP: Latest Flood Alerts)

It’s possible that final totals for the month of May could top 30 inches in parts of Oklahoma, and it appears likely that at least one location will break the official all-time May rainfall record for the entire state, which is 23.95 inches in Miami, Oklahoma, in May 1943.

Keep in mind that slow-moving thunderstorms can produce heavier rainfall totals in localized areas in a short period of time. Also, the exact areas where the heaviest rainfall amounts occur may differ slightly from what is shown on our forecast map given that small-scale details are hard to predict several days in advance.

As always, stay informed about the latest flood watches and warnings for your area. If you are in a vehicle and encounter a flooded roadway, do not attempt to drive through the water. From 1995-2010, 64 percent of flood-related deaths occurred in vehicles. The National Weather Service stresses: Turn around, don’t drown.

Next Week: Dry Hope? 

There are signs that relief from this relentless pattern of rain is on the way as the calendar turns to June next week.

The jet stream may finally make its northward migration, allowing drier, more stable air aloft to take hold in the southern Plains.

While this wouldn’t be strong enough to inhibit all thunderstorms, we think thunderstorm coverage should be much less, with a much lower threat of flash flooding next week in Texas and Oklahoma. However, an extended period of mainly dry conditions is likely for most of Texas and Oklahoma next week.

Instead, next week’s thunderstorm clusters may target the northern and central Plains, roughly from Kansas northward.

Who would’ve thought a drier forecast would be good news in Texas and Oklahoma given the recent long-term drought?

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