HOUSTON — Tropical Storm Imelda is making landfall in Freeport, Texas has a tropical storm warning continues from Sargent to Port Bolivar.

The storm is "likely to produce life-threatening flash along portions of the Upper Texas Coast, including the Houston and Galveston areas," according to the National Hurricane Center.

The latest models show some spots could see 12 to 24 inches of rain. It's not possible to forecast which areas so everyone in SE Texas should stay weather aware.

Galveston ISD has canceled classes for Wednesday. Follow this link for additional closures.

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While it's impossible to tell you what areas will get hammered and which ones won't, it stands to reason that everybody is likely to see tropical downpours that could cause flooding of low-lying areas.

A Flash Flood Watch has been issued for Brazoria, Chambers, Fort Bend, Harris, Liberty, Matagorda, Galveston and Wharton counties from 1 p.m. Tuesday until Wednesday afternoon. This is likely to be extended into Thursday.

Computer models continue to increase the amount of rain we could see over the next 72 hours and it's concerning for sure for a couple of reasons.

HOUSTON RADAR: Tropical Storm Imelda forms in the Gulf

While the ground is dry, it's also like concrete. If we experience rain rates as high as 2 to 3 inches per hour, we'll see much of that turn into run-off that could quickly flood some areas. 

Second, a lot of runoff will likely cause bayous, streams and rivers to rise. If and only if the blockbuster amounts shown in the models come to fruition, we could see swelling of the bayous.

At 1 p.m. Imelda had wind speeds of 40 mph as it moved north. 

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RELATED: Tropical Storm Imelda: School closures in Houston and Southeast Texas

RELATED: How the City of Houston is preparing for the rainy week ahead

RELATED: 5 ways to prepare for potential flooding

RELATED: Gov. Abbott places several state resources on standby in front of possible flooding 

Here's a timeline of what you can expect

Tuesday Afternoon 

Scattered tropical downpours move inland across southeast Texas and Houston. Storms should be moving quickly but may cause some isolated street flooding. Flood threat still low.

Tuesday night and Wednesday morning 

Flash flooding becomes a larger threat as the disturbance moves onshore. Rainfall rates of 2 to 4 inches per hour and the threat for 'training' increases. Flood threat moderate.

Wednesday night and Thursday morning

At this point the ground across Houston and southeast Texas will become saturated. Any heavy downpours that develop and train across the area will quickly spark the threat for flash flooding on roads, creeks and bayous. Rivers will have to be closely monitored as well. Flash flood threat high.

Thursday afternoon and evening  

Some computer models have the system and the rain moving north out of the Houston area Thursday evening. Others have it lingering through Thursday evening until finally exiting on Friday. For now I'll leave the flash flood threat elevated through Thursday night. 

If you live near a low lying area or spot that is prone to flooding stay close to the weather forecast and monitor the radar. Be sure to watch the weather at least once a day on KHOU 11 News and stay weather aware with us as we enter the busy time of hurricane season.

WEATHER RADAR: Track rain & storms across Texas 

Five ways to prepare for flooding

There are five things you can do right now to make sure you’re ready.

1. Register for AlertHouston

Alert Houston is how the City of Houston sends out critical emergency information. It will alert you via email, text, phone call, or push alert. You can get geo-targeted warnings at your location. You can also register up to five addresses.

2. Register for Harris County’s Flood Warning System

FWS monitors rainfall at more than 250 locations along bayous, creeks, and rivers. It will alert users in real time as water levels rise through email and/or text message.

3. Look at Houston’s Flood Prone Map

The City of Houston Office of Emergency Management partnered with Houston Public Works and TxDOT to identify over 100 flood prone roadways. Drivers should check the map before rain events.

4. Download the Transtar App

The Transtar app allows you to monitor road conditions in real time. It also shows regional alerts and active incidents on an interactive map.  (Android users, tap here.)

5. Pay attention to meteorologists

Visit our KHOU Weather page.