Excessive Rainfall threat. Main threat will emerge in TX on Sunday!

The heavy rain threat will be ongoing all of next week to points farther northeast with a cut off very slow moving upper level low.

Current Day 1 Forecast

Day 1 Threat Area in Text Format  

Current Day 2 Forecast

Day 3 forecast below

Severe Storm Risk.  Hit the map for full screen.  Not very high-weak jet stream.  The pattern will be favorable for heavy rains, not severe storms. In fact, because the steering currents/jet stream will be so weak, its exactly what will cause this............the big rain maker will travel very, very slowly northeastward across the Cornbelt next week. 

https://www.spc.noaa.gov/products/outlook/

Current Day 1 Outlook
Current Day 2 Outlook
Current Day 3 Outlook
Current Day 4-8 Outlook

High Temperatures today and Sunday.

Record smashing heat that was along the West Coast.................has started shifted to N.Rockies/N. Plains!!

Pacific Northwest has cooled down. TX is cool from clouds/rain.

The rest of the country close to normal.

Dew points. 70+ on this scale makes it feel uncomfortable(sticky air)!  Humid over the southern parts of the country.......so what's new!

A tad humid Ohio Valley.

Heat and high humidity COMBINED. Feels like temperature. Feeling sultry in the south. NIce N.PLains/Upper Midwest.

Highs days 3-7.

Heat moves around. Most intense heat in parts of the West again. Nice cooling Great Lakes area later in the week.

How do these days 3-7 temperatures compare to average at this time of year?  We are now more than 3 weeks past the climatological time of year when temperatures are the hottest.

Above average West/Rockies to N.Plains.

High temperature departures:

Low Temperature Departures:

Weather system from East Coast back to Texas(where it's becoming much more active).  

https://weather.com/maps/currentusweather

Here is the latest radar image:

http://www.nws.noaa.gov/radar_tab.php

Satellite picture. 

Rains the past 24 hours.    Eastern/ Southern locations favored. 

You can go to this link to see rain totals from recent time periods:

https://water.weather.gov/precip/

Go to precipitation, then scroll down to pick a time frame. Hit states to get the borders to see locations better. Under products, you can hit "observed" or "Percent of normal"

Missouri  to S.Plains still in bad shape....but they got some nice rains that helped. Much more rain is on the way to make an even bigger dent in the long lived drought.

Below are rains compared to average of the last 7, 14, 30 and 60 days. Usually not updated for previous day until late the next day.

https://www.atmos.illinois.edu/~snodgrss/Ag_Wx.html

Drought Monitor. This product is updated every Thursday. Drought will be shrinking.

            http://droughtmonitor.unl.edu/Maps/CompareTwoWeeks.aspx    

Temperature Anomalies from GFS ensembles(fairly reliable product) going out 2 weeks. These maps show the Northern Hemisphere. The map of the US is front center. Look for the state borders in  white.

Today:  Record smashing heat that WAS in the  Pacific Northwest spreading to N.Rockies/N.Plains!  

In 5+ days:

Heat is moving around. Still hottest West......spews east briefly. Brief cool shot Great Lakes.

In 10+ days   Hot West again!!!! Heat moving around...... Some heat spills east to the Northeast.

Day 15  Hottest West .............How much moves east?

Latest 0z run of the Canadian model ensembles. Majority have some troughing dipping down into the Upper Midwest to Northeast. Much uncertainty.....especially on where the heat ridge(which will be there) will be located. Preferred place for ridge is the Rockies...........but it could be anywhere.

The top map is the ensemble average, the maps below are the individual members that make up the average.

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Each member is like the parent, Canadian model operational model.......with a slight tweek/variation in parameters. Since we know the equations to represent the physics of the atmosphere in the models are not perfect, its useful to vary some of the equations that are uncertain(can make a difference) to see if it effects the outcome and how.

The average of all these variations(ensembles) often yields a better tool for forecasting. It's always more consistent. The individual operational model, like each individual ensemble member can vary greatly from run to run.........and represent an extreme end of the spectrum at times. The ensemble average of all the members, because it averages the extremes.............from opposite ends of the spectrum............changes much less from run to run.

360h GZ 500 forecast valid on Aug 24, 2018 00 UTC

Below are some of the 0z GFS individual ensembles at the end of 2 weeks. Alot of disagreement with some still placing the Upper level heat ridge farther east.  

The end of week,  6Z GFS ensemble average shows an upper level ridge building in Western Canada(to just off the coast).........this would be a precursor to downstream troughing and a jet stream aimed toward the Midwest/Northeast with cooling. 

Image URL: http://mag.ncep.noaa.gov/data/gefs-mean-sprd/06/gefs-mean-sprd_namer_360_500_vort_ht.gif

The low skill, longer range CFS model for weeks 3 and 4.

Week 3 carries thru with the week 2 changes taking place on that last GFS ensemble product described above. Heat ridge continues to build back west.........COOL Plains/Midwest to East Coast.

Precip below:

The maps below are from the NWS extended outlooks.  

They are COOLER than yesterday.............except for the West Coast.

The below normal precip in the Northwest Cornbelt and N.Plains is gone. 

The above normal precip in the 6-10 day has expanded northward. 

My opinion is that the cooler temps will verify  for the Midwest eastward but the above precip will occur very early in the period(before day 10) andafter day 10 it will be mostly dry with the upper level ridge rebuilding strongly along the West Coast, well into Canada and a downstream trough in the East with the jet stream aimed in that direction, having cool, dry air masses.

6-10 day Temperature Probability

Precipitation Probability

8-14 day Temperature Probability

Precipitation Probability