Slight Risk of Severe Weather Tuesday

SLIGHT RISK OF SEVERE THUNDERSTORMS TUESDAY

The Storm Prediction Center (SPC) has placed the majority of central and north Texas (from Austin north) in the SLIGHT RISK category for potential severe weather on Tuesday. According to the Storm Prediction Center, a SLIGHT RISK of severe weather means scattered severe storms will be possible. The severe storms that are able to develop are typically short-lived and NOT widespread, however, an isolated intense storm cannot be ruled out. 

Areas shaded in yellow are under a SLIGHT RISK for severe weather...dark green areas are under a MARGINAL RISK

A deep trough of low pressure (a large dip in the jet stream) to our west will continue to get closer to the area through the day on Tuesday and cross the area late Tuesday into Wednesday. Out ahead of this trough, a surface cold front is being pushed east southeast towards central Texas. As this front and the upper level dynamics provided by the trough approach the area, showers and thunderstorms are expected to blossom. The showers and thunderstorms we experienced today are occurring as deep moisture continues to be pulled into the state of Texas ahead of the approaching dip in the jet stream. 

According to the Storm Prediction Center, some of the storms that develop on Tuesday will have the potential to become strong and/or possibly severe with damaging winds in excess of 58mph being the greatest risk. In addition to the potential for some damaging thunderstorm wind gusts in a few spots, the threat for heavy rainfall and deadly cloud to ground lightning will occur with any and all storms that develop. Storms will come in waves through the day on Tuesday as disturbances move across the area from southwest to northeast ahead of the advancing trough of low pressure. Storm chances will eventually come to an end with a broken line of showers and storms late Tuesday afternoon and evening as a Pacific cold front pushes across the area from west to east with a reinforcing shot of cooler and drier air moving in from the northwest early Wednesday morning setting the stage for a beautiful Wednesday, Thursday, and Friday with noticeably more pleasant conditions thanks to a cooler and drier air mass that will infiltrate the region.

Additional rainfall amounts of 1-4 inches will be possible between now and late Tuesday night across central Texas with the heaviest totals being felt along and west of the I-35 corridor. Due to already saturated soils, it will not take a lot of rain for creeks and streams across the area to rise. Remember, if you come across a flooded roadway, TURN AROUND, DON’T DROWN. As always please remain weather aware and keep an eye to the sky. 

This approaching trough of low pressure that is giving us showers and storms is working in tandem with a ridge of high pressure centered across the east coast to steer Hurricane Michael (now forecast to make landfall as a MAJOR category three hurricane with sustained winds of 115 mph and gusts near 140 mph) in the Florida panhandle Wednesday afternoon. In addition to the threat of high winds and torrential rainfall, Michael is also expected to bring a significant storm surge. Here’s a look at key messages from the National Hurricane Center on Hurricane Michael:

As of the 7pm Monday evening advisory from the National Hurricane Center, Hurricane Michael is a category one hurricane with maximum sustained winds of 85 mph. Below is a look at the 7pm Monday evening official forecast track:

Key Messages:

1. Life-threatening storm surge is likely along portions of the

coasts of the Florida Panhandle, Big Bend, and Nature Coast, and a

storm surge warning is in effect for these areas. Residents in these

areas should follow all advice given by their local officials.

2. A hurricane warning has been issued for portions of the Florida

Gulf Coast, and everyone in these areas should prepare for

life-threatening winds associated with the core of Michael.

Damaging winds will also extend inland across portions of the

Florida Panhandle, southern Georgia, and southeast Alabama as

Michael moves inland.

3. Heavy rainfall from Michael could produce life-threatening flash

flooding from the Florida Panhandle and Big Bend region into

portions of Georgia and South Carolina.

To stay up to date with all of the latest information regarding Hurricane Michael, please visit the National Hurricane Center's website by clicking HERE  

Rain Looks Promising

Forecast Discussion

With high pressure positioned well to the east and northeast of Texas, the sea breeze was able to once again push through the area this afternoon. As it did so, it helped to generate some widely scattered showers and thundershowers. With the loss of daytime heating this evening, any remaining showers will quickly fizzle out. The sea breeze is simply a gust of wind that moves in off of the Gulf of Mexico that tries to equalize temperatures. Because land heats up a lot faster than water, low pressure develops and forces "cooler" air over the Gulf of Mexico to rush in land to takes it place. It acts like a mini cool front this time of year.

Sea Breeze Graphic

Saturday
I'm expecting a near repeat of today's weather on Saturday, morning low clouds will give way to a partly cloudy and warm afternoon in the lower to middle 90s with afternoon/evening showers and storms popping up for some folks as the sea breeze moves through the area.

Father's Day & Beyond
Deep tropical moisture associated with an area of low pressure currently located over the northwestern Caribbean and Yucatan Peninsula will move northwest towards Texas over the weekend and approach the Texas coast by Father's Day. This approaching area of low pressure (which the National Hurricane Center is giving a 10% chance of tropical development this evening) will drag copious amounts of Gulf moisture into the Lone Star State for the second half of your Father's Day Weekend into the middle of next week. Because we will have so much moisture in place, I expect widespread tropical showers and storms to blossom up each afternoon beginning on Father's Day with even better chances for widespread tropical showers and storms Monday and Tuesday of next week. These showers and storms will be driven by the heat of the day, becoming widespread during the late morning/afternoon and decreasing each day towards sunset with the loss of daytime heating. Forecast models have been a bit wishy-washy in terms of forecast rainfall accumulation, but I'm thinking given the amount of moisture that's going to be in place, we could easily manage 1-3 inches of rain across the area between now and the middle of next week. Because of the tropical connection, showers and storms that develop will be capable of producing very heavy rainfall in a short amount of time. Another benefit of the added clouds and rain will be cooler temperatures. Afternoon highs after Father's Day (depending on when the rains flare up each day), will likely only manage the upper 80s.

Tropical Moisture Location (as of Friday evening)

Forecast Rainfall Accumulation - now through next Friday
Source: Weather Prediction Center (WPC)

At this point in time, flash flooding is not a concern, as most of this rain looks to fall over several days, but it's always important to remember that if you come across a flooded roadway, turn around, don't drown!

Stormy Days Ahead

Forecast Discussion

An upper level storm system approaching from the west will work together with a slow moving frontal system to increase our chances for showers and thunderstorms, some of which may be strong/severe, across the area beginning as early as tomorrow morning and peaking late Tuesday night into midday Wednesday. By the time this is all said and done, many locations across central Texas have the potential to pick up between 1-2 inches of rain. Some locations may receive less and some locations may receive more.

The Storm Prediction Center based in Norman, Oklahoma has placed our area under the SLIGHT RISK category for severe weather tomorrow through Wednesday. The main threats from the storms that are able to turn severe will be large hail (greater than or equal to 1" in diameter) and strong, gusty winds (greater than or equal to 58 mph). At this point in time, flash flooding does not appear to be a threat, but some minor flooding could occur in areas that are typically prone to flooding during heavy rainfall events. Deadly cloud to ground lightning will be a threat in any storm that develops (weak or severe). Remember, when thunder roars, go indoors.

Pay attention to the Threat Impact Levels Chart in images below

Tuesday Severe Weather Threat
Austin/San Antonio National Weather Service Forecast Office

Wednesday Severe Weather Threat
Austin/San Antonio National Weather Service Forecast Office

Central Texas Forecast Rainfall Accumulation Graphic
Austin/San Antonio National Weather Service Forecast Office

We are in a moderate/severe drought across the area, so beneficial rains are a welcome sight. Hopefully this rain will be more beneficial than troublesome. Another benefit of the rain will be to cleanse the air and outdoor surfaces from the tremendous amounts of spring pollen.

Please stay tuned to the latest weather information and heed all watches and warnings issued by the National Weather Service/Storm Prediction Center. 

Potentially Stormy Weather Pattern Next Week

Forecast Discussion

With the lack of recent rainfall, the drought across the area continues to worsen. Per the latest drought monitor published today (see below), the majority of central Texas is now considered to be in the moderate drought category with areas of severe drought now across eastern Travis County, western Bastrop County, Caldwell, Hays, and Comal Counties.

There are indications in the medium to long range forecast models that some much needed rainfall may be on the way. The Weather Prediction Center (WPC), in their latest 7 day rainfall outlook (see below), is forecasting the potential for 1-3 inches of rain to fall across the area between now and next Friday with the majority of that rain falling during the middle to latter portions of next week.

Friday - The Weekend

With high pressure in place at the upper levels of the atmosphere, the weather will remain fairly tranquil with increasing moisture levels across the area as persistent southerly winds continue to bring Gulf of Mexico moisture back into the area. Late night/morning low clouds can be expected giving way to partly sunny afternoons. Morning lows in the 60s and afternoon highs in the 80s can be expected. Rain is NOT in the forecast this weekend, but some patchy morning drizzle cannot be ruled out. 

Next Week - Stormy Pattern (especially Wed-Fri)

By the beginning of next week, a large trough of low pressure is expected to take shape across the western United States (a dip in the jet stream) that looks to generate an upper level storm system across the desert southwest (a large, cold, pocket of air aloft) that promotes lift and instability in the atmosphere. As this upper low approaches Texas, the counter-clockwise rotation around this upper level storm system will send disturbances, or ripples in the atmosphere across Texas that will each bring with them a chance for showers and storms. As the main upper system approaches the area and combines forces with a surface cold front, our chances for showers and thunderstorms look to increase dramatically for Wednesday-Friday of next week. Given that we are in March, we will need to keep an eye out for some potential severe weather next week.

Heavy Rain Threat

TUESDAY AM STORMS (MAINLY WEST OF AUSTIN)

Showers and thunderstorms likely to move across the Hill Country early Tuesday morning. Per the latest high resolution forecast models, most the storms Tuesday morning will stay west and northwest of the Austin Metro Area. Some of the storms early Tuesday will have the potential to be on the strong side with heavy downpours, frequent cloud to ground lightning, gusty winds, and perhaps some small hail. These storms have the potential to put out a quick 1-2 inches of rain. It is not out of the question for some of these storms to side swipe portions of the Austin Metro Area early Tuesday.

Forecast Radar Tuesday 5AM (HRRR Model)

HEAVY RAIN THREAT LATE TUESDAY INTO WEDNESDAY

***Widespread Showers and Storms likely Tuesday Night into Wednesday***

A cold front moving across the area late Tuesday into Wednesday, upper level energy, and plentiful amounts of Gulf moisture will lead to the development of widespread showers and thunderstorms. These storms will have the potential to drop 1-3 inches of rain across the area along with dangerous cloud to ground lightning. Some isolated locations may receive upwards of 4-5 inches of rain. While some small hail and gusty thunderstorm winds cannot be ruled out, the biggest weather threat is going to be the potential for heavy rain. Should and if flash flooding becomes a concern remember, TURN AROUND, DON'T DROWN

Forecast Rainfall Accumulation Graphic (courtesy of the National Weather Service)