Written by Sig Silber
HEADLINES (Updated 5:04 PM EDT) –
– Heavy rain and potential flooding for the Northeast, Midwest, and the South
– Heat wave continues for much of the western U.S. into Tuesday
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.
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CONUS Focal Points
Short Range Focal Points
Short Range Forecast Discussion NWS Weather Prediction Center College Park MD
446 PM EDT Sun Jul 11 2021
Valid 00Z Mon Jul 12 2021 – 00Z Wed Jul 14 2021
…Heavy rain and potential flooding for the Northeast, Midwest, and the South…
…Heat wave continues for much of the western U.S. into Tuesday…
At the beginning of the short-range forecast period, a low pressure center was located over the Middle Mississippi Valley which will continue slowly to the north-northeast over the next couple of days. A warm front extended east through the Ohio Valley and into the Mid-Atlantic, with a cold front extending southwestward through the Lower Mississippi Valley and the Southern Plains. More unsettled weather is expected in the Northeast over the next couple of days as the slow moving warm front advances northward bringing anomalously high low-level moisture (dewpoints in the low to mid-70s). Widespread heavy rain with embedded thunderstorms are likely.
A Moderate Risk for excessive rainfall is in effect for the greater New York City area Monday. A Slight Risk is in effect for additional portions of eastern Pennsylvania and New York as well as southern New England. Heavy rain totals of 2 inches and higher over an urbanized area which recently saw heavy rainfall, leading to saturated soils, is a significant concern for additional flooding. Heavy rainfall will also be a concern across central portions of upstate New York east through southern Vermont and New Hampshire, where some isolated amounts of 2 to 4 inches are possible through Tuesday morning. For Tuesday, a Slight Risk for excessive rainfall is in effect for portions of upstate New York east of Lake Ontario to the Adirondacks, where isolated rain totals of up to 4 inches are also possible. This may lead to some potential flooding and rises on area rivers, especially over river basins that have received above average rainfall over the past several days.
Marginal Risks for excessive rainfall are in effect further west along the warm front and ahead of the cold front from the Lower Great Lakes south to the Ohio Valley for widespread rain of around 1-2 inches over the next couple of days. Heavy rain and potential flooding is also possible from the Southern Plains to the Southeast as the cold front progresses slowly eastward. A Slight Risk of excessive rainfall is in effect for the the Lower Mississippi Valley and the Tennessee Valley on Monday as mean flow roughly parallel to the front may lead to repeated heavy rainfall over some areas. Rain totals of 1-2 inches are possible with some isolated amounts of up to 4 inches.
Excessive heat will continue to make weather headlines across the western third of the nation. A stubborn upper-level high anchored over the Desert Southwest is the primary factor in the ongoing heat wave, but this is expected to slowly erode some going into the beginning of the week. Highs in the 110s in the Desert Southwest and central California Valleys today should dip back down into the mid-100s for Monday and Tuesday. Widespread heat will also continue over the Great Basin, with highs in the mid-100s Sunday and the upper 90s to 100 Monday and Tuesday. However, this small relative cool down is of little relief to areas that have seen long-term oppressive and above normal temperatures. Excessive heat warnings remain in effect for a majority of locations in the region through Tuesday. Relative above normal temperatures look to hold on the longest over the Interior Pacific Northwest, with highs in the upper 90s to 100 through the forecast period. It is also worth noting that overnight lows have also been impressive with this heat wave, with lows failing to drop below the lower 90s for portions of the Desert Southwest.
Some relief from the extreme heat may arrive in the form of monsoonal showers and thunderstorms each day across portions of Arizona and New Mexico, which will increase in coverage and intensity through the period. A Marginal Risk for excessive rainfall is in effect on Monday with a Slight Risk in effect for Tuesday. The greatest threat is for heavy downpours with rain rates of up to 2 inches per hour that may lead to the rapid onset of flash flooding, especially for arid locations where such rain rates are a more rare event. In addition to the threat for flooding, severe weather is also possible. The Storm Prediction Center has issued a Slight Risk for severe thunderstorms today for the threat of high winds and hail, with a Marginal Risk in effect for Monday.
Elsewhere, below normal high temperatures for July are expected for the Midwest and Central Plains Monday and the Midwest and Southeast Tuesday behind the current storm system, with highs mainly in the 80s. The chance for showers and thunderstorms will increase across the Northern and Central Plains as well as the Central Rockies by Monday evening and into the day Tuesday as a cold front moves south across the region from Canada.
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 July 12 2021 – Friday July 16 2021
Hazards:
– Heavy rain across portions of the Lower Mississippi Valley and Tennessee Valley, Mon, Jul 12.
– Heavy rain across portions of the Middle Missouri Valley and the Middle and Upper Mississippi Valley, Wed, Jul 14.
– Heavy rain across portions of the Central Plains, Middle Mississippi Valley, Ohio Valley, and Great Lakes, Thu-Fri, Jul 15-Jul 16.
– Flooding possible across portions of the Northeast, the Middle Mississippi Valley, the Mid-Atlantic, the Upper Mississippi Valley, the Southeast, the Great Lakes, and the Ohio Valley.
– Flooding occurring or imminent across portions of the Southeast, the Middle Mississippi Valley, and the Southern Plains.
– Flooding likely across portions of the Southeast and the Southern Plains.
– Excessive heat across portions of the Interior Pacific Northwest, Mon-Wed, Jul 12-Jul 14.
– Excessive heat across portions of California, the Southwest, the Central and Southern Great Basin, and the Central Rockies, Mon-Tue, Jul 12-Jul 13.
– Excessive heat across portions of the Central and Northern Great Basin, Mon-Fri, Jul 12-Jul 16.
– Much above normal temperatures across portions of the Northern High Plains, Thu-Fri, Jul 15-Jul 16.
Detailed Summary:
Heavy rain in the central and eastern U.S. as well as the prolonged heatwave in the western U.S. highlight the hazards outlook for the medium-range forecast period (Monday, July 12 – Friday, July 16). At the beginning of the period, a low pressure system over the Middle Mississippi Valley is forecast to move northeastward into Canada by Wednesday (July 14th). A warm front will extend east from the low across the Lower Great Lakes into the Mid-Atlantic and move northward through the Upper Great Lakes and Northeast, while a cold front will extend to the southwest through the Middle and Lower Mississippi Valley into Southern Plains and slowly progress eastward.
An upper-level trough will also be in place over the central U.S. Storms are expected to be ongoing along the cold front across the Lower Mississippi and Tennessee Valleys at the start of the forecast period on Monday (July 12th). High boundary layer moisture in place along the front (dew points in the low to mid-70s) as well as mean southwesterly flow roughly oriented along the cold front associated with the upper-level trough will lead to heavy rain of 1-2 inches with these storms. There is also a chance for heavy rain along the warm front in New England. However, it appears any higher rain totals will remain relatively isolated at this time.
As this first system moves to the northeast and the low pressure center exits into Canada, another system and cold front will move southeastward into the north-central U.S. from Canada on Monday into Tuesday (July 13th). Some storms may be possible during this time frame but heavy rain is not currently expected.
However, on Wednesday, more organized convection is expected to develop along the front, aided by a shortwave trough moving across the Northern Tier. There is some uncertainty on the exact track of the storms and the location for associated heavy rainfall. However, given the high boundary layer moisture once again in place (dewpoints in the mid-70s) as well as the strong signal in model guidance for heavy rainfall of 1-2 inches, with locally higher amounts above 3 inches, a broad area from the Middle Missouri Valley into the Middle and Upper Mississippi Valley has been maintained to account for this potential.
Convection is expected to continue and increase in coverage as the shortwave continues east and the cold front progresses eastward across the Great Lakes into the Northeast as well as southward into the Central Plains, Middle Mississippi Valley, and Ohio Valley on Thursday (July 15th) and Friday (July 16th). Daily heavy rain totals of 1-2 inches with locally higher amounts are expected along the length of the cold front as the high boundary layer moisture remains in place.
In the west, the persistent upper-level ridge that has been in place over the western U.S. will finally begin to weaken some through the forecast period. However, excessive heat and above normal temperatures are still expected across a broad area of the west at the beginning of the period and will continue through the end of the period where subtle ridging remains in place. This excessive heat throughout the period is expected across portions of the western and northern Great Basin, the Wasatch Front of Utah, and the Snake River Valley of Idaho. Highs in the upper 90s to mid-100s are forecast on Monday and Tuesday and will remain in the upper 90s through Friday, providing little relief. Excessive heat is also forecast for the Mojave Desert, the San Joaquin Valley/central California, the Sacramento Valley/northern California, portions of the southern Great Basin, and western portions of Central Rockies on Monday and Tuesday. High temperatures in the 110s are likely for the Mojave Desert and San Joaquin valley, with highs in the upper 90s further north. Highs in the upper 90s to low 100s are expected further east across the Great Basin and western Colorado. Excessive heat will also continue for the Interior Northwest through Wednesday, with highs in the mid to upper 90s forecast.
High temperatures will likely return closer to normal throughout California, the Mojave Desert, and northeast into the Great Basin and western Colorado on Wednesday as the ridge begins to break down. A weak shortwave trough moving east from the Pacific will provide some relief from the hotter temperatures by Thursday for the Northwest as well.
Above normal temperatures in the mid- to upper 90s are also forecast for the Northern High Plains of Montana on Thursday and Friday as subtle ridging increases ahead of the shortwave trough to the west. Although not all locations will see their temperatures peak through the extent of the outlook periods, opted to keep areas a bit broad both location and time wise given the oppressive heat seen over the west the last few weeks. Widespread extreme to exceptional drought across the west is also a concern with the continued hot weather. Besides the heat, there is a signal in model guidance for an increase in storm chances southeast of the ridge, particularly across eastern Arizona. Heavy rain chances look to remain isolated at this time, but could be a concern for flash flooding locally.
In Alaska, an occluding low pressure system currently over the Gulf of Alaska will begin to dissipate by Tuesday. Moist onshore flow ahead of the system may lead to some heavy rain along the southern Mainland on Monday, but the localized nature of any higher amounts and their location in the model guidance preclude an outlook area. Additionally, a low pressure system and associated cold front will move southward across the Far North and eastern Interior Tuesday into Wednesday, with the front becoming stationary across the Interior. Some rain is possible along and ahead of the system across the Interior on Wednesday and Thursday, but model guidance differs as to how heavy the rain is expected to be. Additionally, below normal temperatures are also possible, particularly across the Far North, but do not look to be particularly hazardous at this time.
(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 |