Excessive Rain threat

Elevated the next 2 days in a very long, southwest to northeast corridor. Moves quickly southeast, starting late Tuesday. 

Current Day 1 Forecast

Day 1 Threat Area in Text Format  

Current Day 2 Forecast

Day 3 forecast below

Severe Storm Risk.

With the pattern change featuring a strong jet stream and upper level wave riding the front, then resulting in surface low development, along with increased frontal convergence, along with unstable air, we have the recipe for organized severe storms. 

The highest threat will be from damaging winds, especially if we get a squall line along the advancing cold front............starting Monday Night, into Wednesday. 

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 Tuesday.

The heat surges north one last time the next 2 days. Cold starts diving southeast late Tuesday.

Highs for days 3-7:

The chilly  air will be moderated but still feature temperatures 30 degrees colder than recent days along the Ohio River.

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

 The extreme magnitude of the contrast between cold and warmth weakens as the cold moves southeast quickly and drains out the long lived warmth.

Low Temperature Departures:

Surface features for the same 3-7 day period:

Initial  strong cold front moves off the East Coast. Chilly Canadian high pressure moves in behind it.  Reinforcing cold front this weekend.

Higher dew points have surged northward. Extremely dry air in the N.Plains, will start surging south late Tuesday.

Current Surface features:

Frontal zone defining incredible temp contrast. Low pressure/storm getting ready to develop along front. Michael showing up in the eastern Gulf of Mexico. 

https://weather.com/maps/currentusweather

Latest radar loop.

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

Satellite picture.

Rains the past 24 hours

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......but it's getting even wetter here in early October.

The wet pattern is going to change, starting Wednesday!!!

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....................0Z ensembles from Monday.  More zonal, west to east flow,  less meridional/extreme. Mild to warm temperatures. Much drier pattern than recent days.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

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 23, 2018 00 UTC

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:  Southern edge of cold air in Canada in the northern/central Plains back west! Very warm air to the southeast is moving north 1 last time.

In 5+ days:

Heat ridge in the Southeast finally gone. Cold has swept southeast.

In 10+ days: Cool air surge has run its course. The last of it moves off the East Coast. New pattern with mostly zonal/mild to warm flow from west to east is in force.............already spreading into the N.Plains/Midwest.

Day 15:  Extreme anomalies completely gone. Mild to warm for mid-October across most of the country. Dry.

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

Mild to warm Pacific air masses spread across North America. This would result in lower heating degree days vs average. 

Dry weather in the Midwest to accelerate harvest along with warm temperatures.

Heating degree days(from cold weather) are replacing cooling degree days(from hot weather) in October.

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

Precip below:

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

Huge pattern change. Mild/dried out Pacific air masses move zonally(west to east) across the US. MUCH drier. 

Initially very chilly in the Midsection but the cold air is flushed out during week 2. 

Temperature Probability

Precipitation Probability

the 8-14 day outlooks ArchivesAnalogsLines-Only FormatGIS Data

Temperature Probability

Precipitation Probability

Extreme weather days 3-7. 

Chilly in the Northcentral US. High winds in the Southeast on Wed pm to Thursday from the remnants of Michael. Heavy rains also, that move quickly to the MidAtlantic Coast.