Written by Sig Silber

HEADLINES (Updated 4:12 pm EST) –

– More rain, mountain snow, and gusty conditions out West; Elevated Risk for fire weather in the Plains

– Warmer than normal temperatures from the Four Corners states to the Midwest, chilly temps in the East return to above normal levels by week’s end

– Heavy snow and rain across portions of the Pacific Northwest and the Northern Great Basin next week, as well as flooding across portions of the Southeast and the Mid-Atlantic

This article provides continuous updates for a variety of Weather and Weather-Related Threats as well as a general weather forecast. These are “Live” maps that continually update. Please pay attention to the Mesoscale Events maps — Mesoscale Events are potentially life-threatening situations.

Please share this article – Go to the very top of the page, right-hand side for social media buttons. Also, feel free to send this email to anyone you feel will benefit from it.

For those interested in longer-term forecasts, we just published the new NOAA Seasonal Outlook and it can be accessed here.

Directory

CONUS Focal Points

Short Range Focal Points

Short Range Forecast Discussion NWS Weather Prediction Center College Park MD – 243 PM EST Wed Nov 18 2020

Valid 00Z Thu Nov 19 2020 – 00Z Sat Nov 21 2020

…More rain, mountain snow, and gusty conditions out West; Elevated Risk for fire weather in the Plains…

…Warmer than normal temperatures from the Four Corners states to the Midwest, chilly temps in the East return to above normal levels by week’s end…

The region expected to see the most active weather through the remainder of the work-week is the Northwest where more rounds of showers and mountain snow are on tap this evening and into Thursday. Winter Storm Warnings remain in effect over the northern Sierra Nevada through this evening with snowfall diminishing overnight. The Pacific Northwest can expect unsettled weather to persist through Thursday, but a brief break in the active pattern arrives Friday as high pressure moves in aloft. Mountain snow is also on tap across the northern Rockies with the highest elevations; from the Sierra Nevada and Cascades to the Sawtooth and Teton Ranges, picking up over a foot of accumulating snowfall. In addition, strong winds continue through this evening across the Great Basin and central Wyoming where High Wind Warnings and Wind Advisories are in place. Blustery conditions are also present in the southern and central Plains, which combined with low humidity levels is fostering a favorable fire weather environment. This has led to the issuance of Red Flag Warnings and an Elevated Risk in SPC’s Fire Weather Outlook today. An Elevated risk for fire weather conditions is in place over central and western Nebraska on Thursday.

Much of the eastern half of the Lower 48 can expect mostly dry conditions with the lone exceptions being the eastern coast of Florida and the western Gulf Coast where spotty showers are possible. The tranquil stretch of weather is due to an expansive area of high pressure from the Mississippi Valley to the East Coast. Southerly and southwesterly flow on the backside of the high pressure system is causing much above normal temperatures to engulf the Southwest and Heartland today with high temperatures as much as 30 degrees above normal. Record breaking temperatures are likely to occur from parts of the central Plains to the Desert Southwest today and Thursday. The abnormally warm temperature regime for mid-November spreads east into the Great Lakes and Ohio Valley on Thursday, then eventually reaches the East Coast by Friday where much cooler temperatures currently reside. In fact, some locations in the Northeast could be 25-30 degrees warmer when comparing today’s high temperatures, which are hovering just below freezing over the interior Northeast, to Friday’s where highs may reach 60 degrees.

We try to keep this up to date but if is not you can find the updated version here.

When you click on this image it takes you to the SPC Fire Warning Page and you get a set of maps for Days 1, 2, 3 – 8, etc. You can then click on those for more detailed information. The map is a bit blurry as I tried to make it a bit larger than the map provided by NOAA but should be able to see where the current wildfire risks are. But if you click on this map, you will get to see three maps that show the risk for different time periods.

Thunderstorm Risk

This should play out something like shown in this 60 Hour Forecast Animation

Here is a national animation of weather fronts and precipitation forecasts with four 6-hour projections of the conditions that will apply covering the next 24 hours and a second day of two 12-hour projections the second of which is the forecast for 48 hours out and to the extent it applies for 12 hours, this animation is intended to provide coverage out to 60 hours. Beyond 60 hours, additional maps are available at links provided below. The explanation for the coding used in these maps, i.e. the full legend, can be found here although it includes some symbols that are no longer shown in the graphic because they are implemented by color-coding.

The two maps below break it down by day and may be easier to read.

Now, the Day One and Two CONUS Forecasts: These Maps Update Daily.

Day One CONUS Forecast	Day Two CONUS Forecast
These graphics update and can be clicked on to enlarge. You can see where the weather will be

During the winter much of our weather originates in the Pacific. That is why we pay attention to the near-term history of storms arriving.

Temperature

A version that shows a 20 hour animation and some other views can be found here OR SIMPLY CLICK ON THE IMAGE.

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Day 3 – 7 Hazards

Valid Friday November 20 2020 – Tuesday November 24 2020

Hazards:

– Heavy rain across portions of the Pacific Northwest and the Northern Great Basin, Mon-Wed, Nov 23-Nov 25.

– Heavy rain across portions of the Central/Southern Plains, the Lower/Middle Mississippi Valley, the Great Lakes, and the Ohio Valley, Sat-Sun, Nov 21-Nov 22.

– Heavy rain across portions of the Middle/Lower Mississippi Valley, the Southern Plains, and the Ohio/Tennessee Valleys, Tue-Wed, Nov 24-Nov 25.

– Heavy snow across portions of the Pacific Northwest and the Northern Great Basin, Tue-Wed, Nov 24-Nov 25.

– Flooding occurring or imminent across portions of the Southeast and the Mid-Atlantic.

– Heavy precipitation across portions of mainland Alaska, Sat, Nov 21.

– High winds across portions of mainland Alaska, Sat, Nov 21.

Detailed Summary:

A series of upper-level disturbances will be the impetus for hazardous weather over the CONUS during the medium range period (Saturday, November 21st – Wednesday, November 25th). The first wave of low pressure will arrive over the Pacific Northwest on Friday. As this shortwave propagates east, it will organize an area of surface low pressure along the lee of the Rockies which will later be the focus for heavy rain over the Mid-South into the Midwest on Saturday and Sunday. Light snowfall may mix in some places within the cold sector of this system. Temperatures are likely to remain above average for much of the eastern U.S. throughout the medium range.

Another disturbance is forecast to impact the Pacific Northwest on Monday. This system may produce some heavy rainfall for the region before deepening over the Rockies and generating heavy rainfall over the Middle to Lower Mississippi Valley and Tennessee Valley on Tuesday and Wednesday. A stronger closed upper-level low arrives along the Northwest coast on Tuesday. This potent system is forecast to produce heavier rainfall from the Panhandle of Alaska down to the Pacific Northwest on Tuesday and Wednesday. Heavy snow is also expected for Northern Cascades during this time period.

In Alaska, an upper-level low will spin up over the Aleutians on Friday. This will develop a low pressure system that will generate high winds for the islands and mainland on Saturday. Heavy precipitation will also be a threat over the southwestern mainland on Saturday as the surface low moves toward the Gulf of Alaska. This area of low pressure may produce heavy precipitation and high winds for portions of the Panhandle of Alaska heading into midweek.

(This is updated only during the week) Note the first list is weather highlights, this list is hazards. Not sure there is that much of a difference but they come from two different parts of NOAA. The Day 3 – 7 Hazards List does not update on weekends. But it is still useful as it remains valid for the period of time it covers. Of course, all forecasts are subject to change. Later we show a map of the hazards. Perhaps we should show them together.

Click here for the latest complete Day 3 -7 Hazards forecast which updates only on weekdays. It includes the full discussion which I do not update in this article but only present the highlights.

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Ski Snow Reports

New Feature – Ski Reports. (We may be a tad premature but not by much). It is difficult to find reports that auto-update on-screen (and they are very long) but these links will get you to them – If you have additional suggestions make them in the comments section after every GEI Article and we may add those links. We will try to not have too much overlap as that can add to the confusion.

We will update the above map weekly but more frequent updates can be obtained here.

Snow Forecasts.

Day 1

Day 2

Additional snow information can be found here and here.

We also include drought information in this section.

New November Drought Outlook

Seasonal Outlook Issued October 15, 2020

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Tropical Events

I am replacing the large with three small maps but you can click on them to get larger versions. Even though they are small maps you should be able to tell if there is activity and If I see activity I will make the map where there is activity full size and when available add other related maps.

the Central Pacific.	the Eastern Pacific	the Atlantic and the Gulf of Mexico

Atlantic and Gulf of Mexico

And the Eastern Pacific

Updates on individual named storms can be obtained here.

And the Western Pacific

Weekly Tropical Forecast

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Intermediate-Term Weather Forecast

And shifting to the Alaska and CONUS Intermediate-Term Weather Forecast showing from left to right, Days 1- 5, 6 – 10, 8 – 14 and Weeks 3 – 4 You can click on these maps to have them enlarge, there are larger versions in the Addendum (More Weather the link is shown at the end of this section, and there are larger versions of these maps in the Addendum. Also, the discussions that go with these forecast maps can be found here (first two weeks) and here (Weeks 3 and 4).

First Temperature

And then Precipitation

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Mesoscale Events

The following map shows where mesoscale events are occurring or forecast. If you do not see any areas highlight on this map than there are no mesoscale events taking place or forecast. A mesoscale event is a very serious situation for a very small area and detailed information is provided for these events when they occur or are forecast. If a mesoscale event is shown, click on the map and more detail on the event will be shown.

Two different parts of the NWS issue this map and they are not always in agreement although they are pretty close. They (Norman Oklahoma and College Park Maryland) issue the alerts when they realize the need, so it is best to look on both maps and click one or both if you see areas highlighted.

This next map showing where “Headlines” have been issued for convection (and an animation of the recent movement of storms) should update and you should be able to click on to get additional details but if it does not update when you click on it, click here.

There is a slight difference between convection and thunderstorms. The below map shows where “Headlines” have been issued for Thunderstorms. You should be able to click on the map to get additional details but if it does not update, you can click here.

The map below shows the current wildfire risk which becomes more significant as we move into Summer. When you click on this image it takes you to the SPC Fire Warning Page and you get a set of maps for Days 1, 2, 3 – 8, etc. You can then click on those for more detailed information. The map is a bit blurry as I tried to make it a bit larger than the map provided by NOAA but should be able to see where the current wildfire risks are. But if you click on this map, you will get to see three maps that show the risk for different time periods.

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Now the Day 3 – 7 Hazards Outlook Maps

The orange and red outlined areas are what is most concerning of the forecasted Day 3 – 7 Hazards. This graphic does not update during the weekend. There is a discussion that goes with this graphic and you can access that discussion here.

The following is provided to help the reader relate the maps to how NWS will describe an area of the U.S.

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Now to our More Detailed Weather Report

This graphic is about Atmospheric Rivers i.e. thick concentrated movements of water moisture. More explanation on Atmospheric Rivers can be found by clicking here or if you want more theoretical information by clicking here. The idea is that we have now concluded that moisture often moves via narrow but deep channels in the atmosphere (especially when the source of the moisture is over water) rather than being very spread out. This raises the potential for extreme precipitation events.

500 MB Mid-Atmosphere View

The map below is the mid-atmosphere 3-Day chart rather than the surface highs and lows and weather features. In some cases, it provides a clearer less confusing picture as it shows only the major pressure gradients. This graphic auto-updates so when you look at it you will see NOAA’s latest thinking. The speed at which these troughs and ridges travel across the nation will determine the timing of weather impacts. This graphic auto-updates I think every six hours and it changes a lot. Thinking about clockwise movements around High-Pressure Systems and counterclockwise movements around Low-Pressure Systems provides a lot of information.

Day 3 Above, 6 Below	Day 4 Above,7 Below	Day 5 Above.

Here are the precipitation forecasts. First the cumulative for Days 1 – 3

Then cumulative for Days 1 – 5

Then cumulative for Days 1 – 7

Now we look at the forecast for the Maximum Temperature three days out.

Looking ahead to next week.

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Additional Tools to Obtain Watches and Warnings

Below you will see a number of different maps that are updated in real-time, making this a “live” report. If a part of one or more of the maps shows an area that is highlighted, you can click on it and get the full current report. By having the reader click on these active situations rather than having GEI do so, you will not miss any events in which you might have an interest and which we had not noticed and the page will not get cluttered with warnings, etc that have since expired.

Our focus here is events that are likely to last in the range of six hours but there can be longer or shorter events that are addressed by the Storm Prediction Center which is the main source of the information in this article. Long-term major events like a Hurricane are more likely to be in a separate article. But that may not always be the case. Since in general, all the links on this page transfer you into the NOAA system, in order to get back into this article you need to either close the tab to which you were transferred or click back on the tab that has this article.

Live Warning Maps which If Severe Weather is Shown can be Clicked on to get more detail about these events. If there is a current warning shown on the map, click on the map for additional information related to the event.	These maps are updated as risks are identified.
This is the current graphic showing any mesoscale discussions (MD’s) which are in effect over the contiguous United States. Please read the description of the purpose of our MD’s for further information. Details on all valid MD’s may be found on our Current Mesoscale Discussions page.
Convective Outlooks
This is today’s forecast for organized severe thunderstorms over the contiguous United States. Please read the description of the risk categories for further information. You may find the latest Day 1 Outlook available as well as all Outlooks issued today online.	Today’s Outlook
This is tomorrow’s forecast for organized severe thunderstorms over the contiguous United States. Please read the description of the risk categories for further information. The latest Day 2 Outlook is available as well as all Outlooks that have been issued today.	Tomorrow’s Outlook
This is the day after tomorrow’s (day 3) forecast for organized severe thunderstorms over the contiguous United States. Please read the description of the risk categories for further information. The latest Day 3 Outlook is available as well as all Outlooks that have been issued today.	Day 3 Outlook
This is the day 4-8 forecast for organized severe thunderstorms over the contiguous United States. The latest Day 4-8 Outlook is available as well as all Outlooks that have been issued today. Note: A severe weather area depicted in the Day 4-8 period indicates a 30% or higher probability for severe thunderstorms (e.g. a 30% chance that a severe thunderstorm will occur within 25 miles of any point).	Day 4-8 Outlook
The Thunderstorm Outlooks depict the probability of thunderstorms across the contiguous United States in 4 or 8 hour time periods. The probabilistic forecast directly expresses the best estimate of a thunderstorm occurring within 12 miles of a point. The three probabilistic forecast thresholds are 10, 40, and 70 percent.	Thunderstorm Outlook
Fire Weather Outlooks
This is today’s forecast for organized wildfires over the contiguous United States. Please read the description of the risk categories for further information about this product.	Today’s Outlook
This is tomorrow’s forecast for organized wildfires over the contiguous United States. Please read the description of the risk categories for further information about this product.	Tomorrow’s Outlook
This is day 3-8 forecast for organized wildfires over the contiguous United States. Please read the description of the risk categories for further information about this product.	Day 3-8 Outlook

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