Updraft® - Minnesota Weather News

Harvey’s flooding rains continue; Sunday shower chance in Minnesota

Hurricane Harvey toppled buildings, trees and power lines in parts of southeast Texas Friday night and Saturday.

Harvey also brought torrential flooding rains.

Here's a sample of the damage and flooding in Rockport, Texas, where Harvey made landfall Friday evening:

As of Saturday evening, one hurricane related fatality had been reported in Rockport.

Hurricane Harvey became Tropical Storm Harvey Saturday afternoon, as its maximum sustained winds dropped below 74 mph.

The center of Harvey has become almost stationary, as illustrated in this Saturday afternoon satellite loop from the National Oceanic and Atmospheric Administration’s GOES-16 satellite:

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NOAA visible loop Saturday afternoon, via College of DuPage

GOES-16 is NOAA's newest weather satellite, and it is still in its testing phase.

Harvey's max winds were at 60 mph Saturday evening, according to the National Hurricane Center:

Tropical Storm Harvey Intermediate Advisory Number 26A

NWS National Hurricane Center Miami FL AL092017

700 PM CDT Sat Aug 26 2017

...TROPICAL STORM HARVEY DRIFTING EAST-NORTHEASTWARD...

...TORRENTIAL RAINS WILL CONTINUE...

 

SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION

----------------------------------------------

LOCATION...29.2N 97.4W

ABOUT 40 MI...65 KM NW OF VICTORIA TEXAS

ABOUT 70 MI...115 KM ESE OF SAN ANTONIO TEXAS

MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H

PRESENT MOVEMENT...ENE OR 060 DEGREES AT 2 MPH

MINIMUM CENTRAL PRESSURE...992 MB...29.29 INCHES

 

WATCHES AND WARNINGS

--------------------

CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...

* Port Aransas to High Island Texas

A Tropical Storm Warning is in effect for...

* Baffin Bay to High Island Texas

A Storm Surge Warning means there is a danger of life-threatening

inundation from rising water moving inland from the coastline in the

indicated locations. For a depiction of areas at risk, please see

the National Weather Service Storm Surge Watch/Warning Graphic,

available at hurricanes.gov. This is a life-threatening situation.

For storm information specific to your area, including possible

inland watches and warnings, please monitor products issued by your

local National Weather Service forecast office.

 

DISCUSSION AND 48-HOUR OUTLOOK

------------------------------

At 700 PM CDT (0000 UTC), the center of Tropical Storm Harvey was

located by Doppler radar near latitude 29.2 North, longitude 97.4

West. Harvey has been drifting east-northeastward for the past few

hours. Little additional motion is anticipated during the next few

days.

Maximum sustained winds have decreased to near 60 mph (95 km/h)

with higher gusts. Additional weakening is expected during the next

day or two.

Tropical-storm-force winds extend outward up to 115 miles (185 km)

from the center. San Marcos Regional Airport recently reported

sustained winds of 40 mph (65 km/h) and a wind gust of 53 mph

(85 km/h).

The estimated minimum central pressure is 992 mb (29.29 inches).

 

HAZARDS AFFECTING LAND

----------------------

RAINFALL: Harvey is expected to produce additional rain

accumulations of 15 to 25 inches over the middle and upper Texas

coast through Thursday. Isolated storm totals may reach around 40

inches in this area. Elsewhere during the same period, Harvey is

expected to produce total rain accumulations of 5 to 15 inches

farther south toward the lower Texas coast, farther west toward the

Texas Hill Country and southwest and central Louisiana. Rainfall of

this magnitude will cause catastrophic and life-threatening

flooding. A list of rainfall observations compiled by the NOAA

Weather Prediction Center can be found at:

www.wpc.ncep.noaa.gov/discussions/nfdscc1.html

STORM SURGE: The combination of a dangerous storm surge and the

tide will cause normally dry areas near the coast to be flooded by

rising waters moving inland from the shoreline. The water is

expected to reach the following heights above ground if the peak

surge occurs at the time of high tide...

Port Aransas to Sargent...4 to 7 ft

Sargent to High Island including Galveston Bay...2 to 4 ft

High Island to Morgan City...1 to 2 ft

The deepest water will occur along the immediate coast near the

area of onshore winds, where the surge will be accompanied by large

and destructive waves. Surge-related flooding depends on the

relative timing of the surge and the tidal cycle, and can vary

greatly over short distances. For information specific to your

area, please see products issued by your local National Weather

Service forecast office.

WIND: Tropical storm conditions are occurring in portions of

the tropical storm warning area, and are likely to persist along

portions of the coast through at least Sunday.

SURF: Swells generated by Harvey are affecting the Texas,

Louisiana, and northeast Mexico coasts. These swells are likely to

cause life-threatening surf and rip current conditions. Please

consult products from your local weather office.

TORNADOES: A few tornadoes are possible through Monday near the

middle and upper Texas coast into far southwest Louisiana.

Some areas in southeastern Texas have already seen over 10 inches of rain:

Harvey could bring an additional 10 to 20+ inches of rain to southeastern Texas from Saturday night through Thursday:

rt0826harvqpf
NWS/WPC/National Hurricane Center

Catastrophic flooding is expected in parts of southeastern Texas:

This Houston forecast says it all:

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NWS Houston

They are expecting periods of heavy rain in Houston for several days.

Minnesota rain chances

The official rainfall total was 1.58 inches at Minneapolis-St. Paul International Airport from Friday night through Saturday afternoon.

Scattered showers are possible on Sunday, especially over eastern Minnesota and western Wisconsin.

The National Oceanic and Atmospheric Administration's North American Mesoscale forecast model shows the potential rain pattern:

rt0826rad2
NOAA NAM simulated radar for Sunday and sunday evening, via tropicaltidbits

An isolated thunderstorm is also possible Sunday afternoon.

Still cool

We only reached 67 degrees for our official Twin Cities metro area high temp on Saturday.

We should top 70 degrees on Sunday, but northeastern Minnesota will see 60s:

rt0827h2

Our average high is 79 degrees this time of year in the Twin Cities.

Twin Cities highs should reach the lower 70s Monday, then upper 70s Tuesday and lower 80s on Wednesday.

Programming note

You can hear my live weather updates on Minnesota Public Radio at 7:49 a.m. Thursdays and Fridays, and at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.