Tag Archive for: tropical storm

Grace Now Expected to Track Farther South, Turn Into Tropical Storm Tuesday

Tropical Depression Grace at 11 AM EDT was moving West at approximately 15 mph, according to the National Hurricane Center. If Grace stays on the current track, it will move between Cuba and the Yucatan.

No Direct Impacts to Upper Texas Coast Expected

At the present time, Jeff Lindner, Harris County Meteorologist, expects no direct impacts to the upper Texas Coast, with the possible exception of some high tides and large swells.

Greater impacts with squalls and higher seas appear more likely along the lower Texas Coast into the weekend. 

As always with tropical systems, check forecasts frequently for changes.  Remember, forecasts for this storm have shifted direction a whopping 90 degrees in less than a day. Yesterday afternoon, NHC forecast the storm to head toward the Florida panhandle; last night it was headed toward Texas. Today, they show it heading toward the Mexican mainland.

Cone of uncertainty for Grace. Remember: the storm has an equal chance of making landfall anywhere within the cone.

Current Conditions

Maximum sustained winds are currently 35 mph with gusts to 45. Grace will move over Haiti this evening and strengthen to a tropical storm south of SE Cuba Tuesday morning. Cuba and the Cayman Islands have already issued tropical storm warnings.

Strong trade winds will continue to push the storm west.

Air Force Reserve and NOAA Hurricane Hunters were both able to locate a center for Grace–and measured several possible areas of tropical-storm-force winds.

High pressure over the western Atlantic is forecast to slide westward over the southeastern United States during the next several days, which should keep Grace on a westward to west- northwestward trajectory for the entire 5-day forecast period.

Forecast Maps

Grace is the lower, elongated storm. The purple area is Fred. And the red area in the Atlantic is a third is tropical depression 8.
Tropical-storm-force winds could hit the Mexican mainland on Friday.

All available models closely agree on the new track.

Models are starting to show consensus on Grace’s track.

Intensity Forecast

Grace’s intensity forecast remains complicated by interaction with land and the possibility of some westerly shear during the forecast period. However, the southern shift in the forecast track takes the center of Grace over very warm 30 degrees Celsius waters in the northwestern Caribbean Sea. Therefore, Lindner expects gradual strengthening.

Once the system reaches the Gulf of Mexico, shear should decrease, says Lindner, and conditions will support additional strengthening. Many models bring Grace to hurricane intensity by the end of the forecast period.

Favorable upper level and sea surface conditions along the path of Grace over the southern Gulf support some of the stronger solutions and tropical systems in this area of the Gulf tend to have a history of quick development. NHC is currently indicating Grace nearing the Mexican coast as a tropical storm, but a hurricane is certainly possible.

Posted by Bob Rehak on 8/16/2021 at noon based on information from NHC and HCFCD

1448 Days since Hurricane Harvey

TS Hannah Continues to Veer toward Valley; Threat to Houston Reduced

Overnight, TD 8 turned into Tropical Storm Hannah. Hannah’s track continues to take it toward Corpus and the Rio Grande Valley. The shift in direction compared to earlier projections means wind and rainfall threats to Houston are reduced. However, tropical storm warnings remain up for most of the Texas coastline, including San Luis Pass to the Rio Grande Valley.

Rainfall Amounts

Hanna should produce heavy rains, but the heaviest will fall in South Texas.

While portions of south Texas could see 10 to 15 inches of rain this weekend, rainfall amounts in the Houston area should average 3-5 inches along the coast and 1-3 inches inland.

Jeff Lindner, Harris County Meteorologist
Infrared imagery shows building of Hannah.
Rainfall accumulation for storm duration
Total accumulation in north Harris County is likely to be only 1-2 inches from Hannah.

Of course, that should hold down the risk of flash flooding in the Lake Houston Area, but Lindner says the Weather Service will likely issue flash flood warnings for portions of SE Texas later today. NOAA currently gives the north Houston area only a marginal chance of flash flooding.

Houston has only a 5-10% chance of flash flooding from Hannah.

Hannah Could Strengthen to 65 MPH

National Hurricane Center expects Hanna to strengthen and bring tropical-storm-force winds to portions of the Texas coast. NHC brings Hanna to a 65mph tropical storm at landfall. How long it takes any inner core to form today will determine if Hanna could potentially become a weak hurricane as suggested by some of the hurricane models.

Most tropical storm force winds should miss Houston.

Winds in the Lake Houston Area will not be that strong, of course, but could still reach 20 mph, according to forecasters.

Not the Weekend for Offshore Boating

Lindner says, “Wave heights near the center of Hanna will build today. As the system intensifies, waves could reach 10-15 ft tonight. Some of this wave action will move toward the upper TX coast with seas building today into the 4-6 foot range and 6-9 foot range tonight into Saturday. Large swells generated by the system will result in wave run-up and elevated tides of 1-3 feet starting later today and lasting into much of Saturday along the upper and mid TX coast. Minor coastal flooding will be possible at times of high tides in the typical sensitive areas along the coast.”

Forecast track shows Hannah coming onshore Saturday at 1PM in south Texas.

In summary, the brunt of the storm should miss us. But we will still get sideswiped.

The organization of Hanna will need to be monitored closely today and tonight. For up-to-the-minute status reports and forecasts, visit the National Hurricane Center’s website.

Posted by Bob Rehak on 7/24/2020 at 9:15 am

1060 Days since Hurricane Harvey

Tropical Storm Predicted to Make Landfall on Saturday; Rainfall Estimates Increased

The National Hurricane Center (NHC) has begun advisories on Tropical Depression 8 in the central Gulf of Mexico. Tropical Storm Watches have been issued for the Texas coast from Port Mansfield to High Island including Matagorda and Galveston Bays.

Recent model guidance brings the system to the Texas coast with 48-60 hours over the Gulf waters. Some show the system over Gulf water for 72 hours as the system slows near the coast. NHC forecasts a 45mph tropical storm slamming the middle Texas coast on Saturday. 

Houston should be on the dirty side of the storm.

If this does reach tropical-storm strength, it would be named Hannah. Ironically, another H storm hit Houston called Harvey in 2017. But Harvey happened a full month LATER in the season.

Next USAF reconnaissance flight will depart at 4:45 a.m. CDT tomorrow morning and will determine if a tropical depression or tropical storm has formed.

Source: NHC

Rainfall

Jeff Lindner, Harris County meteorologist, says predicted rainfall rates have increased. Widespread rainfall amounts of 3-5 inches will be possible along and generally south of HWY 105 with higher isolated totals. North of HWY 105 rainfall amounts of 1-3 inches will be possible. There is likely to be swaths of higher rainfall amounts where training bands develop, but where this may occur is difficult to pinpoint at this time range.  

Channel 13 tonight predicts that some areas west of Houston could record a three day total of 14-15 inches of rain because of the slow speed of the storm.

Posted by Bob Rehak on 7/22/2020 at 10:30 p.m.

1058 Days since Hurricane Harvey

 

Buzzing The Mouth Bar: Low Altitude Flyover at 30 MPH Takes 1 Minute 9 Seconds

It’s hard to get a feeling for the enormity of the West Fork mouth bar in a still photo. Something more than half a mile long is reduced to 1200 pixels. That fundamentally alters the scale between nature and humans. Instead of being a thousand times bigger, it’s a hundred times smaller. That does not produce the same emotional impact. It’s like looking at a picture of a mountain instead of standing at the base of one and feeling dwarfed as you look up.

Video Comes Closer to Capturing Imensity

However, tonight, at sunset, I flew a drone over mouth bar and captured the entire flight on video. At 30 miles per hour, it took 1 minute and 9 seconds to get from one end to the other.

The rapidly vanishing San Jacinto West Fork mouth bar. Mechanical dredging reduces the size a little more every day.
Looking south from Scenic Shores in King’s Point across mouth bar toward FM1960 Causeway downriver.
Looking west toward West Lake Houston Parkway.
Excavators working western tip of mouth bar. They shaver one row after another off, as if they are nibbling an ear of corn.
From the upstream to downstream tip measures more than half a mile.
At the eastern end, it almost look as if a bored dredging is carving his initials in the bar so that they can be seen from outer space.
Looking south across the eastern edge toward the FM1960 bridge again.

Tonight, as we watch Tropical Storm Cristobal dump torrential rains on Mexico, it’s hard to escape thinking of Hurricane Harvey. It dumped torrential rains on Houston and formed this monster mouth bar almost overnight. Remember, like an ice berg, the part you see above water is only a tiny percentage of what you can’t see below water.

Thinking of Cristobal, Remembering Harvey

As I look at the cloudless skies and soft sunset, I can’t help but wonder. Will Cristobal miss us. Or is this just the calm before the storm?

Cristobal has produced life-threatening flash flooding in Mexico and Central America. The National Hurricane Center forecasts it to move northward across the Gulf of Mexico on Friday. Risks include storm surge, rainfall and wind impacts this coming weekend across the US Gulf Coast from Texas to Florida. NHC reiterates that it’s too soon predict the exact location, timing and magnitude of these impacts.

Posted by Bob Rehak on 6/3/2020

1009 Days since Hurricane Harvey

TD 3 Close to Tropical Storm Strength; Dumping Torrential Rains Over Mexico, Central America

Confidence is increasing that a tropical system will be moving northward through the Gulf of Mexico by this weekend. It will threaten some portions of the US Gulf coast. However, the National Hurricane Center advises that it’s still too early to pinpoint where the greatest impacts may be.

Harris County Flood Control Meteorologist Jeff Lindner advises residents along the Gulf coast to fully stock hurricane kits and have plans ready to enact. “By Sunday morning, it is likely there will be a tropical storm in the central Gulf of Mexico,” he says.

Source: NHC. Indicates conditions as of 10a.m. CDT on 6/2/2020.

At This Moment…

Slow-moving Tropical Depression Three (TD 3) is still in the Bay of Campeche and:

  • CLOSE TO TROPICAL STORM STRENGTH
  • LIFE-THREATENING HEAVY RAINFALL AND FLOODING CONTINUES OVER PORTIONS OF MEXICO AND CENTRAL AMERICA.

Summary of Watches and Warnings

A Tropical Storm Warning is in effect for Campeche to Puerto de Veracruz. A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area, in this case within the next within 24 to 36 hours.

Current Location and Conditions

At 1000 AM CDT (1500 UTC), the center of Tropical Depression Three was located near latitude 19.5 North, longitude 92.6 West. The depression is moving toward the west near 3 mph (6 km/h). The depression is forecast to move slowly southwestward or southward this afternoon and tonight, and meander over the southern Bay of Campeche through late Wednesday.

NHC forecasts the center of the cyclone to remain near the coast of the southern Bay of Campeche tonight through Thursday. Maximum sustained winds are near 35 mph with higher gusts. Some strengthening is forecast during the next 48 hours, and the depression is likely to become a tropical storm today.

USAF plane recorded flight-level winds of 44 kts.

The minimum central pressure reported by an Air Force Hurricane Hunter plane is 1005 mb (29.68 inches).

TD 3 A Rainmaker

NHC expects TD 3 to produce total rain accumulations of 10 to 20 inches with isolated maximum amounts of 25 inches over parts of the Mexican states of Tabasco, Veracruz, and Campeche.

The depression is also expected to produce total rain accumulations of 10 to 15 inches over northern Chiapas and other Mexican states, Quintana Roo and Yucatan.

Additional rainfall of 10 to 15 inches, with isolated amounts of 25 inches is expected along the Pacific coasts of Chiapas, Guatemala, and El Salvador. Some of these Pacific locations received 20 inches of rain over the weekend, and storm total amounts of 35 inches are possible.

Rainfall in all of these areas may produce life-threatening flash floods and mudslides.

Wind Probabilities

Tropical storm conditions are expected to first reach the coast within the warning area tonight.

Source: NOAA. Probably Tracking of TD 3 and earliest arrival of tropical storm force winds.

It is important for users to realize that wind speed probabilities that might seem relatively small at their location might still be quite significant. A chance exists that a damaging or even extreme event could occur that warrants preparations to protect lives and property.

Key Takeaways

  • Deadly flooding has already occurred in portions of Guatemala and El Salvador, and the depression is expected to bring additional heavy rainfall to portions of southern Mexico, Guatemala, Honduras, and El Salvador, which could cause life-threatening flash flooding and mudslides.
  • Tropical storm conditions are expected along the coast of Mexico where a tropical storm warning is in effect.
  • The system is forecast to begin moving northward across the Gulf of Mexico by this weekend. However, it is too soon to specify the location and timing of any potential impacts along the U.S. Gulf Coast. Interests in these areas should monitor the progress of this system through the week and ensure they have their hurricane plan in place as we begin the season.

Houston Forecast For the Week

Today, mostly sunny with light winds. Expect similar conditions on Wednesday, with the possibility of scattered showers and highs of around 90 degrees.

The second half of the week will see warmer weather as high pressure continues to build over the area. We are likely to see high temperatures in the low- to mid-90s. Mostly sunny skies and only slight rain chances during the afternoon hours. Nights will be warm and muggy, in the 70s.

The location of a high pressure system to our north late in the week will likely determine the track of TD 3. Monitor forecasts closely.

Posted by Bob Rehak on 6/2/2020

1008 Days after Hurricane Harvey

Lake Level Reports in Advance of TS Imelda; Where to Find Up-to-Minute Info During Storm

Overnight, the offshore low that had only a 10% chance of developing into a tropical system, turned into a tropical depression and then a tropical storm called Imelda.

Houston Under Flash Flood Watch

As of 6 p.m. Monday evening, Harris County and the entire Houston area is under a flash flood watch.

For the latest updates visit the National Weather Service site.

Projected Path Of Storm Between US59 and I-45

If the storm stays on its present trajectory, the center should go right through the Lake Houston area. Note in the graphic above that the heaviest rainfall will be east of US59 along a line between Houston and Livingston.

Rainfall Totals

The NWS predicts the three-day total rainfall for the storm could reach 6-8 inches, though professionals caution that much higher amounts are possible. For instance, if you live east of US59 and the track of Imelda, according to Harris County meteorologist Jeff Lindner, you might get up to 10-15 inches.

As the storm approaches from the southwest, the Lake Houston area will be on the dirty side, meaning we will get higher rainfall amounts than further west.

Lake Levels Down To Create Extra Buffer Against Flooding

In advance of the storm, the Coastal Water Authority is lowering Lake Houston. The normal elevation is at 42.5 feet. As of this writing, the Coastal Water Authority shows the pool level at 41.19 feet, about 1.25 feet below normal for a planned maintenance project.

However, effective immediately, the Lake level will be lowered to 40.9 feet, 2.6 feet below normal. This will create an extra buffer against flooding.

Houston City Council Member Dave Martin says, “All gates will remain open until the inclement weather threat leaves the area. After the weather threat has passed, gates will stay open until a level of 41.5 feet is reached allowing for the planned maintenance project to resume.”

The SJRA has lowered the level of Lake Conroe according to its seasonal plan. Lake Conroe is currently at 198.71 feet, a little more than 2 feet below normal. The plan called for 199; evaporation took the rest. Currently the SJRA is releasing 0 cubic feet per second. Check the SJRA website for up to the minute reports.

Dry Ground Will Absorb Initial Rainfall, Then Look Out

Because of extremely dry weather during July, August and early September, the ground should absorb much of the initial rain. However, because the rate could exceed 1-2 inches per hour at times, runoff will rapidly increase.

The first threat from this storm will be street flooding. Secondarily, it will be bayou and river flooding. You can track the latter at Harris County Flood Warning System and make sure you check out their near-real-time inundation feature.

Protective Actions

Be Prepared.  People should bring their pets inside and delay travel or outdoor activities during periods of heavy rainfall.  If travel is unavoidable, reduce your speed to avoid hydroplaning.  

If a Flash Flood Warning is issued for your area, DO NOT travel.  

Property owners should ensure that street drains and ditches are clear of debris, so storm water can flow without obstructions. Blockages of drains, ditches, and culverts are the most frequent cause of flooding in neighborhoods.

Clear Street Drains

Secure items that might float away in heavy rain and become lodged in drains or culverts. Avoid street parking to protect your vehicle and allow clear passage for response vehicles.

Turn Around, Don’t Drown®

Do not drive through flooded areas.  If you see water covering the road, do not attempt to cross it.  Only a few inches of water can float a vehicle . If you find yourself in a dangerous situation where your vehicle is taking on water, get out of the vehicle, get to a higher position, and call 911.   

Monitor Official Sources for Current Information 

Harris County Flood Warning System (harriscountyfws.org), Houston TranStar (houstontranstar.org), and the National Weather Service Houston/Galveston Forecast Office (weather.gov/hgx).

Monitor Stream, Bayou, and Creek Conditions

Rain may move repeatedly across the same area, causing creeks and bayous to rise and possibly exceed their banks.  Stay informed of current conditions and avoid traveling near creeks and bayous.

Avoid Traveling during Periods of Heavy Rain

Rain can reduce visibility and prevent you from seeing the road ahead, which could lead to accidents.

Posted by Bob Rehak at 6 pm Tuesday, 9/17/19

749 Days since Hurricane Harvey

Hurricane Likely for Louisiana Coast; Tropical Storm Force Winds Could Hit Houston on Saturday

NOAA predicts Invest 92L will become Hurricane Barry and hit southwest Louisiana by Saturday morning. That could leave Houston with tropical storm force winds in the 45-70 mph range.

Current forecasts indicate landfall in southwest Louisiana on Saturday morning with the storm strengthening to 85mph just before landfall.
Tropical storm force winds in the 40 to 70 mph range could also hit Houston on Saturday morning. Intensity depends on your location. See map above.
Definite rotation showing, but not yet wound tight. Hurricane hunter planes will fly into the storm this afternoon and weather stations along the coast have doubled their upper air soundings.

Watches Likely To Extend Westward Later Today or Early Thursday, Potentially Include Upper Texas coast

Mid level circulation over the east-central Gulf of Mexico continues to develop. Current ship and buoy data in the central and eastern Gulf of Mexico indicate surface winds of 20-35 knots are already being experienced under deep convection. The US Air Force will fly the area early this afternoon to determine if/where a center of circulation has formed.

NOAA and USAF plan multiple low- and high-level missions. Effective today, weather offices along the US Gulf coast will begin launching upper air soundings every 6 hours instead of every 12. 

Track Remains Uncertain

There is still considerable uncertainty concerning the track of the storm. Adjustments remain possible and all residents within the error cone should make preparations.

85 MPH Winds Predicted at Landfall

The National Hurricane Center predicts an 85 mph hurricane before landfall in Louisiana. Much of this intensification occurs within the last 24 hours before landfall. While conditions in the near term (next 24-36 hours) are generally favorable for development, consolidation of the inner core will take some time. Much of the development should occur as the system nears the coast.

Tropical storm force winds in the 40 to 70 mph range could hit Houston – also on Saturday morning.

Jeff Lindner, Harris County Meteorologist, feels, “This will likely be a case where an intensifying hurricane is approaching the coast on Saturday.”

Storm Surge Watch In Effect for Texas Coast

Tropical storm and hurricane conditions are likely along portions of the Louisiana coast starting Friday and more likely into Saturday. Large long period swells will move into the upper Texas coastal waters starting late Thursday and building Friday into the weekend. This could push tides up along the Gulf facing beaches late Friday into the weekend (Bolivar).

Should the forecast track adjust westward any, impacts to the upper TX would be increased.

Recommended Actions

A large portion of southeast Texas remains in the official error cone. If the track shifts westward again, as it did last night, it could produce greater impacts to our area.

  • Have hurricane plans ready to be enacted if the track shifts to the west.
  • Stock hurricane supplies.
  • Monitor forecasts frequently. 

Posted by Bob Rehak on July 10, 2019 at 12:30pm

680 Days since Hurricane Harvey

Invest 92L Now Offshore; First Hints of Circulation

Chances of Formation Increase to 70% in 2-Day Outlook

As of 2PM EDT Tuesday, the National Hurricane Center (NHC) again increased the chances of Invest 92L turning into a tropical storm. This morning, the two-day outlook said 50%. Now it’s 70%. The 5-day outlook remains at 80%. The animated GIF below shows the first hints of circulation. An Air Force reconnaissance plane is scheduled to fly into the storm tomorrow if necessary.

Since this morning, the chances of Invest 92L turning into a tropical storm have increased from 50% to 70% in the two-day outlook issued by the National Hurricane Center.
Five-hour loop showing first hints of circulation offshore Florida Panhandle.

Center Now in Northeastern Gulf

According to the NHC, a broad low-pressure area has emerged over Apalachee Bay in the northeastern Gulf of Mexico. Environmental conditions are conducive for tropical cyclone formation and development over the next several days, and…

… a tropical depression is likely to form by late Wednesday or Thursday while the system moves westward across the northern Gulf of Mexico.

Heavy Rainfall Potential, But More to East

This disturbance has the potential to produce heavy rainfall from the Upper Texas Coast to the Florida Panhandle during the next several days. In addition, this system could produce wind and storm surge impacts later this week or this weekend from Louisiana to the Upper Texas coast. Continue to monitor the storm at least twice a day.

Uncertainty still high; track uncertain, though all models now suggest landfall east of Houston.

The satellite image below shows infrared imagery. Note how the moisture has built up in the eastern Gulf in the last three hours. It now occupies an area from south Louisiana to south Florida.

24-hour satellite infrared loop shows explosion of convection in northeastern Gulf.

Where to Find Most Current Information 24/7

Official:

National Hurricane Center

NOAA (National Oceanographic and Atmospheric Administration)

National Weather Service

Harris County Flood Warning System

National Weather Service Advanced Hydrologic Prediction Service

USGS Water on the Go App

San Jacinto River Authority

Coastal Water Authority

Other:

Mikes Weather Page

Weather Nerds

Stay dry.

Posted by Bob Rehak on 7/9/2019 at 3:15pm

679 Days since Hurricane Harvey

Tuesday AM Invest 92L Update: Chances of Tropical Formation Keep Increasing

The chances of Invest 92L becoming a named tropical storm have increased to 50% in the two-day forecast and 80% in the five-day forecast, according to the National Hurricane Center. That’s the bad news. The good news for the Houston area: most models now predict the storm will make landfall in Louisiana.

Jeff Lindner, Harris County meteorologist caps predicted rainfall totals at 1 to 3 inches for now, but with the understanding that totals could go significantly higher.

Invest in this context means “area of investigation.” A weather system receives this designation when forecasters start to track something serious more closely.

Uncertainty Remains High at This Time

Because the center of this storm is still over land at the moment, it’s hard to predict. Models diverge widely. Those that take the storm further south into the Gulf result in stronger winds and higher rainfall totals because the storm will remain over water longer.

However, some models predict the storm will remain closer to shore as it tracks westward through the Gulf. Those models suggest lower winds and less rainfall. The current radius of circulation of the storm is 150 nautical miles. (One nautical mile = 1.15078 miles.)

Net: forecasts are all over the map at the moment. Uncertainty remains high.

Suggested Actions

Your best bet is to:

  • Monitor forecasts twice a day
  • Check and stock hurricane kits and have plans ready to be enacted this week
  • Be ready to enact plans by the middle to end of this week
  • Follow trusted weather sources for information (National Hurricane Center, Houston/Galveston National Weather Service, West Gulf River Forecast Center and local government) for any recommendations

Graphical Predictions

From Mikes Weather Page as of Monday evening.
Numbers on each track indicate hours from 6 UTC, Tuesday morning. If the red model is correct, the storm would hit the Texas/Louisiana border by 6am Saturday morning.

Where to Find Most Current Information 24/7

Official:

National Hurricane Center

NOAA (National Oceanographic and Atmospheric Administration)

National Weather Service

Harris County Flood Warning System

National Weather Service Advanced Hydrologic Prediction Service

USGS Water on the Go App

San Jacinto River Authority

Coastal Water Authority

Other:

Mikes Weather Page

Weather Nerds

Good luck!

Posted by Bob Rehak on 7/9/2019

679 Days since Hurricane Harvey