Written by Sig Silber
HEADLINES (Updated 3:56 PM EST) –
– Winter storm setting up over the Upper Midwest on Thursday and Friday
– High Wind Warnings over Montana and portions of the Northern/Central Plains
– Elevated to Critical fire weather possible over Southern California on Thursday into Friday
– Heavy precipitation across portions of the Northeast Saturday
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 – 328 PM EST Wed Jan 13 2021
Valid 00Z Thu Jan 14 2021 – 00Z Sat Jan 16 2021
…Winter storm setting up over the Upper Midwest on Thursday and Friday…
…High Wind Warnings over Montana and portions of the Northern/Central Plains…
…Elevated to Critical fire weather possible over Southern California on Thursday into Friday…
A developing storm will bring considerable snow over the Upper Midwest Thursday and into Friday. Rain and snow will develop over parts of the Northern Plains overnight Wednesday. The snow will move into parts of the Upper/Middle Mississippi Valley on Thursday, with rain and snow moving into the Great Lakes and Ohio Valley by Thursday evening. There will be a few pockets of rain/freezing rain over parts of the Upper Midwest on Thursday. Overnight Thursday, the rain will extend into the Tennessee Valley. The snow will continue over the Midwest on Friday, with some areas seeing 10 inches of snow over the Upper Mississippi Valley. By Friday evening, rain and snow will move into parts of the Northeast. On the west side of the storm, the pressure gradient will be strong, producing high winds. The NWS has issued High Wind Warnings over parts of the Northern High Plains and the Northern/Central Plains through Friday. The snow and wind will produce hazardous driving conditions.
Meanwhile, high pressure builds over the Northern Intermountain Region as upper-level ridging develops over the West Coast. The ridging and downslope wind will aid in producing high temperatures in the mid-80s. A strong surface pressure gradient is expected across most of the Plains between a strong surface-high in the Great Basin and a low-pressure area traversing Southern Canada. This is expected to result in widespread windy conditions across most of the Plains/High Plains. A strong offshore pressure gradient is expected to be ongoing Thursday morning across Southern California, resulting in 20 to 35 mph winds with 50+ mph wind gusts expected in terrain-favored areas of Southern California. These factors will contribute to an elevated fire weather risk for Los Angeles and Ventura counties, where the strongest winds are anticipated. Furthermore, a front will move onshore over the Pacific Northwest on Friday morning, moving into the Northern High Plains by Friday evening. The system will produce rain and higher elevation snow over the Northwest and snow over parts of the Northern Intermountain Region on Friday.
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
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Day 3 – 7 Hazards
Valid Saturday January 16 2021 – Wednesday January 20 2021
Hazards:
– Heavy precipitation across portions of the Northeast, Sat, Jan 16.
– Heavy rain across portions of the Southeast, the Lower Mississippi Valley, and the Southern Plains, Tue-Wed, Jan 19-Jan 20.
– Flooding occurring or imminent across portions of the Southeast, the Pacific Northwest, and the Northern Great Basin.
– Flooding likely across portions of the Pacific Northwest.
– High winds across portions of southern mainland Alaska, Sat, Jan 16.
– High winds across portions of northern mainland Alaska, Sat-Sun, Jan 16-Jan 17.
– Heavy precipitation across portions of the Alaska Panhandle and mainland Alaska, Sat-Tue, Jan – High winds across portions of the Alaska Panhandle and mainland Alaska, Mon, Jan 18.
Detailed Summary:
Throughout the medium range period (Saturday, January 16 – Wednesday, January 20) the upper-level pattern will be dominated by a pair of deep lows and significant troughing on both sides of the CONUS. An upper-level low positioned over the Ohio Valley and Lower Great Lakes is forecast to propagate northeast Saturday into Sunday, deepening in the process. Concurrently at the surface, an occluded low pressure/frontal system is expected to sweep through the Northeast, bringing a mix of heavy rain and snow as well as moderately gusty winds to the region through early Sunday morning. Similarly to yesterday, guidance suggests areas closer to the coastline and at lower elevations will likely receive heavy rain, while snow is expected to be the main form of precipitation at locations inland, at higher elevations, and downwind of Lake Ontario in northern New York where there is potential for lake effect snow. Models also indicate that precipitation type changes and rain/snow mixes are possible throughout the Northeast, making it unlikely that any one region will experience either rain or snow exclusively. Therefore, the whole region will be marked as at risk for heavy precipitation. As the low pressure/frontal system moves through the Northeast, temperatures in interior New England and Maine are expected to be between 12 and 15 degrees above normal, bringing daily temperatures above freezing. This could serve to melt some of the snow pack already in place and, mixed with the heavy precipitation event and above average streamflow, may cause or exacerbate flooding along streams and rivers.
In the beginning of next week, troughing over the western half of the country is forecast to precede the development of a second deep upper-level low over the Southwest. As this feature starts to develop, shortwave energy at the surface will fuel mountain snows in the Rockies on Monday and Tuesday and in the Washington Cascades on Wednesday. While the snowfall is not expected to be heavy enough to be hazardous, there are isolated areas that may see up to 8″ of snow. Simultaneously, a new low pressure/frontal system will emerge in southern Texas on Sunday and remain relatively stationary throughout the remainder of the period, kept in place by high pressure to the northeast. Once the deep low over the Southwest is formed a change in the upper-level flow pattern will force the surface high pressure to recede Monday into Tuesday. No longer impeded by high pressure, the low pressure/frontal system is expected to bring heavy rain to the Gulf Coast states Tuesday into Wednesday. The heavy rain will be especially hazardous along the western Texas and Louisiana coasts where high rainfall totals that could reach 2+” in 24 hours mixed with highly saturated soils could enhance the potential for rain-induced flooding.
Non-hazardous above normal temperature anomalies for both maximum and minimum temperatures will be present all around the CONUS throughout the period. Most notably, the northern Great Plains will experience above normal highs throughout the period, while the entire Northern Tier is forecast to have daily lows significantly higher than normal, with some isolated areas exceeding their normal lows by 25 to 30F over the weekend.
In Alaska, a tight pressure gradient is forecast to develop over the northern Mainland between a deep low in the Gulf of Alaska and a strong high in the Arctic Ocean Saturday and Sunday, producing high winds over and around the Lisburne Peninsula. Additionally, a series of frontal systems are forecast to move through the Gulf of Alaska during the period, bringing a virtually constant string of heavy precipitation to the coast from the Southcentral region through the Alaska Panhandle until a lull on Wednesday. While these systems may generate significant waves, they are expected to remain predominantly offshore. Onshore winds associated with these systems will also pose a threat to coastal regions, specifically to the southern Mainland on Saturday and northern Panhandle on Monday, where wind gusts could potentially reach and exceed hazardous levels. Similarly to the CONUS, maximum and minimum temperatures are forecast to be well above normal throughout Mainland Alaska. While maximum temperatures may reach 25F above normal, minimum temperatures will likely reach or exceed 40F above normal in some areas, a significant reprieve from the cold!
(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 December Drought Outlook
Seasonal Outlook Issued November 19, 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
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 |