Written by Sig Silber
HEADLINES Updated 4:17 PM and 5:40 PM EDT) –
– Heavy rain and severe thunderstorms possible for portions of the Northeast and Lower Great Lakes this evening
– Severe weather and scattered flash flooding to impact parts of the Northern High Plains and Central Plains tonight, shifting into the Midwest on Wednesday
– Heat wave continues for much of the western U.S. through Wednesday, while monsoonal moisture produces flash flood concerns throughout the Southwest and southern Utah
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
351 PM EDT Tue Jul 13 2021
Valid 00Z Wed Jul 14 2021 – 00Z Fri Jul 16 2021
…Heavy rain and severe thunderstorms possible for portions of the Northeast and Lower Great Lakes this evening…
…Severe weather and scattered flash flooding to impact parts of the Northern High Plains and Central Plains tonight, shifting into the Midwest on Wednesday…
…Heat wave continues for much of the western U.S. through Wednesday, while monsoonal moisture produces flash flood concerns throughout the Southwest and southern Utah…
In typical mid-July fashion, the main weather stories across the Lower 48 over the next few days include severe thunderstorms, heavy rain, and excessive heat. Through tonight, areas of severe weather and instances of flash flooding are possible for parts of the Northeast, Lower Great Lakes, and into the Ohio Valley. A warm and humid airmass south of a lifting warm front will fuel thunderstorms capable of producing isolated tornadoes, damaging wind gusts, large hail, and intense rainfall rates. The greatest chance of seeing impacts associated with these thunderstorms this evening will be found across Upstate New York and much of Pennsylvania.
Meanwhile, an upper-level shortwave is expected to spark severe thunderstorms across the Northern High Plains this evening, which could impact parts of South Dakota and northern Nebraska overnight. The Storm Prediction Center has issued an Enhanced Risk (level 3/5) of severe weather from northeast Wyoming to southwest South Dakota. Severe wind gusts and large hail are the main concerns across this region.
By Wednesday, the threat of severe thunderstorms shift into the Midwest and Upper Great Lakes ahead of an advancing cold front and strengthening area of low pressure. SPC has issued an Enhanced Risk for severe weather on Wednesday that includes the northern half of Iowa, southern Minnesota, and central/southern Wisconsin. Flash flooding will also remain possible as thunderstorms interact with an abundance of atmospheric moisture, with over 3 inches of rain possible in certain locations that experience multiple rounds of storms. The aforementioned cold front and associated thunderstorms are forecast to push into Michigan and the Middle Mississippi Valley on Thursday.
For the West, monsoonal moisture is expected to continue producing scattered showers and thunderstorms through Thursday over parts of Arizona, Utah, and New Mexico. Rainfall amounts in excess of 1 inch can produce flash flooding in particularly sensitive areas. Flash Flood Watches have been issued.
Heat will also remain a concern throughout central California and the Intermountain West before slightly cooler temperatures arrive on Thursday. Highs into the upper-90s and low triple digits will be felt throughout the region, including as far north as interior Washington and northern Idaho on Wednesday.
Above average temperatures are forecast to shift into the Northern Rockies and Northern High Plains by Thursday. With ongoing heat for much of the West and widespread extreme drought conditions in place, wildfires may be easier ignited and more capable of spreading uncontrollably throughout this part of the country.
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 Friday July 16 2021 – Tuesday July 20 2021
Hazards:
– Heavy rain across portions of the Central Plains, the Lower Mississippi Valley, the Central Appalachians, the Tennessee Valley, the Middle Mississippi Valley, the Mid-Atlantic, the Southern Appalachians, the Southeast, the Southern Plains, and the Ohio Valley, Sun-Tue, Jul 18-Jul 20.
– Heavy rain across portions of the Central Plains, the Northeast, the Central Appalachians, the Middle Mississippi Valley, the Mid-Atlantic, the Southern Appalachians, the Great Lakes, and the Ohio Valley, Fri-Sat, Jul 16-Jul 17.
– Flooding possible across portions of the Southeast, the Middle Mississippi Valley, the Great Lakes, and the Ohio Valley.
– Flooding possible across portions of the Middle Mississippi Valley, the Great Lakes, the Ohio Valley, and the Upper Mississippi Valley.
– Flooding occurring or imminent across portions of the Southeast, the Middle Mississippi Valley, and the Southern Plains.
– Flooding occurring or imminent across portions of the Southeast, the Middle Mississippi Valley, and the Southern Plains.
– Flooding likely across portions of the Middle Mississippi Valley.
– Excessive heat across portions of the Northern Rockies and the Northern Great Basin, Sun-Tue, Jul 18-Jul 20.
– Excessive heat across portions of the Northern Plains, Fri-Tue, Jul 16-Jul 20.
Detailed Summary:
The medium range forecast period (Friday, July 16th to Tuesday, July 20th) will feature a rather stagnant synoptic pattern, including a stationary closed low off the coast of British Columbia, an amplifying ridge over the Four Corners, and a weak trough propagating through the Great Lakes and Northeast by early next week. This weather pattern is expected to lead to numerous chances for thunderstorms and heavy rain to the Central Plains, East Coast, and South.
With the eastward progression of the upper trough Friday morning, an associated cold front and low pressure wave is forecast to traverse the Great Lakes before swinging south through the Central Plains, Middle Mississippi Valley, and Northeast through the weekend. Downpours will quickly exit Michigan by Friday, with lingering thunderstorms capable of producing higher rainfall rates from the Northeast into the Central Plains through Sunday. As the aforementioned frontal boundary slowly stalls throughout the Middle Mississippi Valley beginning Monday, continued reforming rounds of convection can be expected to spark and track southeastward into portions of northern Arkansas and western Tennessee.
By Tuesday, the front is forecast to sag further south toward the Lower Mississippi Valley and further serve as a catalyst for thunderstorm development over the area. A broad Heavy Rain area was added over much of the South and Mid Atlantic toward the end of the forecast period based on the ensemble signal for heavy rain in the region, although uncertainty with the event precludes a more focused Heavy Rain area.
Elsewhere, before the upper-level ridge strengthens over the Rockies late this weekend/early next week, additional monsoonal moisture is expected to reach parts of the Southwest. Scattered shower activity is forecast, but rainfall amounts below an inch will keep any rain below hazard levels at this time.
Heat is also expected to remain a concern throughout parts of the West and north-central United States during the medium range period. The highest temperature anomalies are currently expected over the Northern High Plains, where high temperatures could enter the triple digits for several consecutive days beginning on Friday. Hot weather and above average highs into the mid-90s are forecast across North Dakota and into northern Minnesota as well, but these values currently don’t reach hazardous criteria. Nonetheless, much of the Dakotas, northeast Wyoming, and the western half of Minnesota are experiencing severe to exceptional drought that will likely worsen due to the upcoming heat and lack of rain. Most of the Northern Rockies and Great Basin won’t get a break from the ongoing oppressively hot summer. Above average temperatures are forecast through early next week, with highs into the upper-90s and low triple digits across lower elevations.
For Alaska, a general increase in precipitation is expected to enter western portions of the state by Saturday. Some isolated heavy rains atop above average streamflows in Northwest Alaska on the 18th-20th will be monitored for a potential Heavy Rain area in future updates.
(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
We will resume snow coverage in the Fall
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Drought Coverage
We include drought information in this section.
More information can be found here.
July Drought Outlook.
Seasonal Outlook Issued May 20, 2021
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Tropical Events
Atlantic and Gulf of Mexico
The Eastern Pacific
The Central 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
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 |