Written by Sig Silber
HEADLINES (Updated 3:56 PM EST) –
– Significant ice storm to develop over the Mid-Atlantic on Friday evening into Sunday evening
– Winter storm to impact Washington State and Oregon through Sunday
– Significant Winter Storm to Arrive over the Southern Plains on Sunday into Monday
– Bitter arctic air to remain entrenched across the Plains and Mississippi Valley
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.
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For those interested in longer-term forecasts, we just published the new NOAA Seasonal Outlook and it can be accessed here.
Readers can scan through this article or jump to where they want to go via the links to the right. To get back to the Directory, hit the back arrow at the top of the URL bar on your screen. But in many cases, one of my Editors has graciously inserted a Return to Directory link to click so that is even easier. This is so high tech that I hardly believe it. |
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CONUS Focal Points
Short Range Focal Points
Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 322 PM EST Fri Feb 12 2021
Valid 00Z Sat Feb 13 2021 – 00Z Mon Feb 15 2021
…Significant ice storm to develop over the Mid-Atlantic on Friday evening into Sunday evening…
…Winter storm to impact Washington State and Oregon through Sunday…
…Significant Winter Storm to Arrive over the Southern Plains on Sunday into Monday…
…Bitter arctic air to remain entrenched across the Plains and Mississippi Valley…
Bitterly cold air will engulf the Plains with temperatures 35 to 55 degrees below average. A quasi-stationary front at the leading edge of the cold air mass will remain over the Southeast through Sunday evening. An area of low pressure moving along the coast/up this boundary will spread precipitation in the form of rain/freezing rain and sleet across the Mid-Atlantic and Northeast Saturday and Sunday. While the probability for significant icing (>0.25″) has decreased, there is still good potential for more than 0.1″ from northern North Carolina through central Virginia and into the I-95 corridor from Washington, D.C. to Philadelphia, Pennsylvania on Saturday. Locally more than 0.25″ is still likely. Light ice accumulations are likely as far north as New York City and Southern New England on Sunday. The same storm will produce rain and embedded thunderstorms over parts of the Southeast through Sunday evening. Ice accumulation on trees & power lines could lead to power outages. Ice accumulation on sidewalks and roads may make travel difficult.
A storm just off the Northwest Coast will move onshore overnight Friday, moving southeastward to the Four Corners Region by Sunday. The system will produce widespread snow across the mountains and into Washington and Oregon’s lowlands through Sunday. Significant snowfall is forecast for both Portland and Seattle, with several inches likely from Friday evening into Saturday. Additionally, icing in excess of 0.25″ is forecast for parts of northwest Oregon through Sunday. Significant disruptions to travel are likely to continue with ice, snow, and wind, contributing to power outages.
Upper-level dynamics will help produce snow across the Northern/Central Rockies into the Central Plains Friday night into the Middle Mississippi Valley. It will continue into parts of the Great Lakes and Ohio Valley on Saturday, with a short break over parts of the Plains and Mississippi Valley on Sunday. Furthermore, the very cold air over the relatively warm Lake Superior will produce lake-effect snow over parts of the Upper Peninsula of Michigan through Sunday evening.
A major winter storm is expected to develop out over the Southern Plains Sunday into Monday, with a large area of snow, sleet, and freezing rain expected. While confidence is high on an impactful winter storm, there remains uncertainty with the location and magnitude of the heaviest snow, ice, and rain/freezing rain. However, it appears likely that there will be significant travel disruption and concern for power outages across a large area of the Southern Plains going into early Monday. Snow will develop over parts of Southwest/Southern Rockies overnight Saturday, with snow developing over the Central/Southern Plains on Sunday morning. The snow will spread into parts of the Middle/Lower Mississippi Valley. Rain will develop along the Western Gulf Coast also on Saturday evening into Sunday evening.
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 40 hour animation and some other views can be found here
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Day 3 – 7 Hazards
Valid Monday February 15 2021 – Friday February 19 2021
Hazards:
– Heavy precipitation across portions of California and the Pacific Northwest, Mon-Tue, Feb 15-Feb 16 and Thu-Fri, Feb 18-Feb 19.
– Heavy snow across portions of the Northern Rockies and the Northern Great Basin, Mon-Tue, Feb 15-Feb 16 and Thu-Fri, Feb 18-Feb 19.
– Heavy snow across portions of the Northern Rockies, Mon, Feb 15 and Thu, Feb 18.
– Heavy snow across portions of the Central Rockies, Mon, Feb 15
– Heavy snow across portions of the Central Great Basin, Mon-Tue, Feb 15-Feb 16.
– Heavy snow across portions of the Southern Rockies and the Southwest, Tue, Feb 16.
– Heavy snow across portions of the Middle/Lower Mississippi Valley, the Tennessee Valley, the Ohio Valley, the Great Lakes, and the Central Appalachians, Mon, Feb 15.
– Heavy snow across portions of the Northeast, and the Great Lakes, Tue, Feb 16.
– Heavy precipitation across portions of the Lower Mississippi Valley, the Tennessee Valley, the Ohio Valley, the Central Appalachians, the Mid-Atlantic, and the Northeast, Mon-Tue, Feb 15-Feb 16.
– Heavy rain across portions of the Southern Appalachians and the Mid-Atlantic, Mon-Tue, Feb 15-Feb 16.
– Heavy precipitation across portions of the Lower Mississippi Valley, the Tennessee Valley, the Ohio Valley, the Central Appalachians, the Great Lakes, the Mid-Atlantic, and the Northeast, Wed-Fri, Feb 17-Feb 19.
– Heavy rain across portions of the Lower Mississippi Valley, the Central/Southern Appalachians, the Tennessee Valley, the Mid-Atlantic, and the Southeast, Wed-Fri, Feb 17-Feb 19.
– Much below normal temperatures across portions of the Northern/Central/Southern Rockies, the Northern/Central Plains, and the Southwest, Mon-Tue, Feb 15-Feb 16.
– Much below normal temperatures across portions of the Northern/Central/Southern Plains, the Upper/Middle/Lower Mississippi Valley, the Tennessee Valley, the Ohio Valley, and the Great Lakes, Mon-Fri, Feb 15-Feb 19.
– Heavy precipitation across portions of mainland Alaska, Wed-Thu, Feb 17-Feb 18.
Detailed Summary:
During the medium range period (Monday, February 15th – Friday, February 19th) upper-level troughing over the central U.S. will act as a double whammy for the CONUS with respect to frigid temperatures and very active weather all across the country. On Monday, a moisture-rich low pressure/frontal system moving onshore from the eastern Pacific will serve as the impetus for heavy snowfall in the higher elevation Cascade and Olympic Mountains and heavy rain along coastal northern California, Oregon and Washington through Tuesday. As the low pressure/frontal system progresses southeast through the western terrain Monday into Tuesday it will leave behind a trail of snow extending from the Northern Great Basin and Rockies through the Southwest, the heaviest of which is expected to fall in the higher elevation mountain ranges. A few days later another low pressure/frontal system is forecast to move onshore from the eastern Pacific, bringing a second round of heavy rainfall to the low lying coastal regions as well as heavy snowfall to the high elevation mountain ranges of the Pacific Northwest, the Northern Great Basin, and the Northern Rockies Thursday into Friday.
Shifting focus further east, a major winter storm that is forecast to develop over the Southern Plains Sunday will begin moving northeast early Monday, guided by a packet of upper-level shortwave energy. With frigid temperatures permeating much of the country, significant amounts of snow, sleet, and freezing rain will accompany system. On Monday, heavy snow will be possible from the Lower Mississippi Valley to the Central Appalachians, with the greatest potential for 6+” of snow expected in the Ohio Valley, while portions of the Lower Mississippi and Tennessee Valleys will carry the highest risk for icy conditions. As the storm system continues on its northeastern trajectory it will give one final push on Tuesday, likely bringing heavy snow to the Northeast, inundating the I-95 corridor with mixed precipitation, and soaking portions of the Southern Appalachians and Mid-Atlantic with heavy rain. Though only a few days out, forecast uncertainty still remains in regards to the exact path of the storm track as well as the location of the rain/snow line and heaviest snowfall. Even a small shift in the storm track can produce significant changes, however, the fact still remains that this multi-day storm will affect a large portion of the country and produce significant hazards that have the potential to impact travel, produce power outages, and threaten personal safety.
As if one far reaching storm system in the medium range wasn’t enough, a second system is expected to develop on Wednesday, following an almost identical track to the first. As two low pressure/frontal systems coalesce into one over Texas, shortwave energy over the Southern Plains and a warm front moving towards the Southeast are forecast to begin producing snow and rain, respectively. Guided by a strong upper-level shortwave, the newly formed low pressure/frontal system will propagate from the Southeast to the Northeast Wednesday through Friday, bringing snow, mixed precipitation and rain to many of the same areas hit a few days prior. While the models are currently in general agreement that the heaviest rain will likely fall over the southern states and Mid-Atlantic, there is still a significant disparity in the storm track in the guidance that areas of snow and mixed precipitation cannot confidently be distinguished. Therefore, the remaining area impacted by this second system is marked as heavy precipitation. As with the first storm, this system will also carry the potential to produce significant hazards and will continue to be watched over the coming days.
Throughout the period, high pressure at the surface will continue its reign of forcing bitter cold temperatures over the central U.S. While much of the eastern Rockies and western Great Plains will feel some relief after Tuesday, temperatures well below normal will keep their tightest grip over the Central/Eastern Plains and Mississippi Valley. On Monday and Tuesday, the most anomalously cold air is expected to settle in the Central and Southern Plains and break over 40 daily low record temperatures, as low temperatures dip to between 30 and 40 degrees below normal. By mid-week temperatures are expected to become slightly more moderate throughout the central U.S., with daily low temperatures in most places reaching closer to or above zero and plateauing at approximately 10 to 25 degrees below normal. Conversely, the Ohio Valley will cool down briefly on Wednesday as the high pressure system settles over the region, dropping daily low temperatures approximately 20 degrees below normal. These widespread anomalously low temperatures can pose a threat to health and safety and should be taken seriously in all affected locations, particularly in the North/Central Plains and Upper Mississippi Valley where low temperatures in the negative teens and 20s could cause frostbite on exposed areas of skin in a matter of minutes.
Over Alaska, a series of deep low pressure/frontal systems are forecast to pass over the Aleutians early in the week, bringing some moderate rain to the region. In the latter half of the week, multiple weaker systems will make their way through the Gulf of Alaska, bringing precipitation to the Southern Mainland and Panhandle as they move onshore. While precipitation over the Panhandle is expected to be moderate, recent model guidance has significantly increased the amount of precipitation expected to fall over the Southern Mainland Wednesday and Thursday, suggesting hazardous levels could be reached or exceeded for the region. Additionally, below normal low temperatures are forecast for portions of the eastern Interior Monday and Tuesday, however, they are not anticipated to be low enough to be hazardous.
(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 February Drought Outlook
Seasonal Outlook Issued January 21, 2021
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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
For those interested in more detail, there are additional weather maps and information in the MORE WEATHER Addendum. The link to the Addendum is here. |
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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
Current watches, warnings, and advisories issued by the agencies of the National Weather Service. Hazards should show up in the various maps but the below links will take you to all outstanding watches and warnings in each category which may include some categories not covered in the various maps or difficult to find. So if there is a category of interest, click on the appropriate link below. |
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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 | |
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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 |