As of early afternoon on Saturday Harvey was about to be downgraded to a strong tropical storm after slamming into the Texas coast as a Category 4 monster hurricane packing 130 mph sustained winds. Residents along the coast are just now starting to assess the initial damage from this first major blow. However, the big rain event that is Harvey is just now getting started.

(Harvey’s rains expand over Eastern Texas at 245 PM EST. Image source: National Weather Service.)

According to the National Hurricane Center, the storm’s forward speed has now slowed down to about 2 miles per hour in a north-bound direction. Meanwhile, its shield of encircling rains is expanding to cover most of eastern Texas. These rains are very intense — producing accumulations of more than 1 inch per hour in many locations. And with Harvey stalling out, such heavy rains are expected to persist over basically the same region and at a similar high intensity for at least the next four days. After that time, Harvey is expected to persist and rains of lighter, but still flood-producing force, may continue to fall over parts of Texas for up to five more days.

(Harvey has already dumped nearly 15 inches of rain on some locations. Despite this fact, NOAA is still predicting more than 20 inches of additional rain. Some models are indicating that final totals could range from 40-60 inches in some locations after a 6-10 day rain event. Image source: NOAA.)

It’s worth noting that though up to 15 inches of rain have already fallen from Harvey, the longer range models still show in excess of another 20 inches coming from the storm over the next week. Many models indicate that more than 40 inches of rain could fall in total. And some of our best models yesterday indicated a potential for up to 60 inches in some locations by the time all is said and done.

In other words, this storm is far from over. The main event, in which Harvey may ultimately produce historic rainfall totals, is just getting ramped up. So now is not the time to relax our guard.

(UPDATED 1)

Links:

See Notes on Climate Change’s Influence on Harvey Here

The National Hurricane Center

National Weather Service

NOAA

Rainfall Rising Nearing 15 Inches in Some Locations

Global Forecast System Model Reanalysis