Excessive rain threat...............still high by Florence. New area in the Midwest early this week.

Current Day 1 Forecast

Day 1 Threat Area in Text Format  

Current Day 2 Forecast

Day 3 forecast below

Severe Storm Risk. Maybe a tornado with Florence.  Hit the map for full screen.

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 Monday.   Widespread warmth..........even hot in a few spots. Cool Northwest.....moving to N.Plains.  Cool and wet under Florence's remnants

Highs days 3-7. Widespread heat but very chilly air invades the north and sinks a bit south. Southern 1/2 of the US stays hot to very warm all week.

New cold surge Northwest, then Northern Plains/Upper Midwest, then Northeast.

How do these days 3-7 temperatures compare to average at this time of year?  We are now 8 weeks past the climatological time of year when temperatures are the hottest.

 Well above average.............but average in mid September is not that hot anymore.

Huge contrast between cold blue anomalies N.Plains and very warm red anomalies south.

High temperature departures:

Low Temperature Departures:

Dew points. 70+ on this scale makes it feel uncomfortable(sticky air)!  

More humid air has been returning.

Heat and high humidity COMBINED. Feels like temperature.

Remnants of Tropical Depression Florence. New  major weather system in the N.Plains.  

https://weather.com/maps/currentusweather

Here is the latest radar image.  Tropical Depression Florence will continue to steal the show. Radars are showing less definition with the circulation but the heavy rains are still there............but shifting now. westward.

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

Satellite picture.      

Very well defined Florence in the Carolinas!

Rains the past 24 hours.  Not much................except over a foot along the coast in North/South Carolina.

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"

Too wet in a huge area from massive September rains!

Drier last week, which is minimizing problems to the crops but wet again this week in the Upper Midwest. Flooding from Florence is happening.

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.

Bountiful rains for most of the Cornbelt..............and points eastward and westward. This increased yields in August!!!

But September brought too much rain!  Drying out now.

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

Drought Monitor. This product is updated every Thursday. Drought has been shrinking but still persists in Texas.........this measure takes into account the long term precip/sub soil moisture and goes back over MANY months.

Top map is this week. Map below it was last week.

            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/tomorrow:   New cool surge Northwest pushing across the Northern Tier this week. Very warm Plains to Northeast today, sinking south this week.

In 5+ days:

Very warm East. Cold in Canada hitting N.Plains, Upper MIdwest/Northeast later this week.

In 10+ days:

Positive Anomalies Southeast to Midwest. Chilly West.

Day 15  Chilly Rockies/Plains?? How far will the cold extend? Magnitude? Massive uncertainty!

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

End of week 2....................12Z ensembles from Sunday-just updated.  Discombobulation and disagreement!! I'm leaning towards a ridge west, trough east pattern by late week 2 and beyond.
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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 Oct 01, 2018 12 UTC

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

Extreme Upper level ridging into Northwest Canada.  Cool and dry downstream in the Midwest.

Septembers gradually get cooler, almost every year. Heating degree days(from cold weather) will soon be replacing cooling degree days(from hot weather) as being the most important as we get into October.

Check in tomorrow to read something different............."low skill" (-:

Precip below:

NWS service extended maps for days 6-10, then 8-14. Looking pretty wet in much of the country. Very warm southeast half, chilly west/northwest 1/4...........to across the northern tier.

Temperature Probability

Precipitation Probability

Temperature Probability

Precipitation Probability