Excessive Rain threat

Moving east then out the next day..........until the next system in the Upper Midwest over the weekend/next week.

Current Day 1 Forecast

Day 1 Threat Area in Text Format  

Current Day 2 Forecast

Day 3 forecast below

Severe Storm Risk.

Pretty quiet. 

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 Friday.

 Cool air pushes  has pushed southeast......stays very warm far southeast.  

Highs days 3-7.

 Very chilly to cold air in the North.  Warmth battles back. The warmth wins for southern 2/3rds.    CDD's from heat still in the south. But most significant HDD's of the season in the N.Plains.

How do these days 3-7 temperatures compare to average at this time of year?

 Above average Southern 2/3rds..........still some CDD's. Well below normal N.Plains.

Low Temperature Departures:

Surface features for the same 3-7 day period:

Initially strong cold fronts coming from Canada, moving southeast and stalling/dying (as they encounter a stout and building upper level ridge), that trigger rains.......more rain as they encounter higher moisture and slow down. 

Upper level ridge  stronger the past 2 days for this period.

Dew points.

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

Higher dew points are in the southeast.

Much, MUCH drier air northern 1/2.

Current Surface features:

Stalled front Midatlantic to South, new system Upper Midwest.

https://weather.com/maps/currentusweather

Latest radar loop.

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

Satellite picture.

2 huge cloud masses.

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"

Soil moisture anomaly:

Too wet in a large area from one of our wettest Septembers in history!  

The 2nd map gets updated once a week.

Rains compared to average for the last 7, 14, 30 and 60 days. 

Usually not updated for previous day until late the next day.

Note how wet it's been over the past 60 days over eastern 2/3rds of the country!

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

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

End of week 2....................12Z ensembles from Thursday.  There will be a deep upper level low/trough in Canada with widespread cold extending south into the northern parts of the US during week 2. Some members have the upper level ridge in the far Southeast trying to hold on! In addition, there is a more zonal, west to east component to the air in the northern states at the end of the period which may start to erode the cold eventually.  Also, this product seems to not have much upper level ridging in W.Canada on many solutions, which is going to be a key element to getting the forecast right downstream.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

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 12, 2018 12 UTC

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

Extreme Upper level ridging Alaska to West Coast has been a constant theme for the past 10 days as well as the downstream cold air in Canada that gets into the Northern US. Todays run shows  this trying to hold together. Also, the cold in Canada may be running out/modifying with time.

Precip is very uncertain.

Heating degree days(from cold weather) are 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:

National Weather Service 6-10 day, 8-14 day outlooks.

The forecasts below are similar to the last 10 days or so.  Cold Northern Plains, very warm Southeast and wet everywhere. 

There is guidance that makes a case for the  flow becoming more zonal later in week 2......west to east. This would moderate the extremes in temperature. The jet stream along the US/Canadian border is still likely to be pretty strong, so the pattern may be fairly active and wet.

Temperature Probability

Precipitation Probability

the 8-14 day outlooks ArchivesAnalogsLines-Only FormatGIS Data

Temperature Probability

Precipitation Probability

Extreme weather days 3-7

Heavy rain this weekend into early next week. This has been on weather models for over a week now. 

Speculative heavy rain events in the 8-14 day period.........on top of Iowa.  This would be the same area with wet weather in the days leading up to that area. This is unfavorable for harvesting. There is a potential for excessive wetness that will not just delay harvest but could cause other issues.