This article focuses on what we are paying attention to in the next 48 to 72 hours. The article also includes weather maps for longer-term U.S. outlooks (up to four weeks) and a six-day World weather outlook which can be very useful for travelers.
First the NWS Short Range Forecast. The afternoon NWS text update can be found here after about 4 p.m. New York time but it is unlikely to have changed very much from the morning update. The images in this article automatically update.
Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Wed Nov 20 2024
Valid 12Z Wed Nov 20 2024 – 12Z Fri Nov 22 2024…Back-to-back powerful Pacific storm systems to impact the West Coast
through the end of this week with heavy rain, life-threatening flooding,
strong winds, and higher elevation mountain snow……Near blizzard conditions are possible through this evening across the
northern Plains……Heavy snow is likely throughout parts of the central Appalachians
beginning on Thursday, with a separate burst of snowfall possible across
northeast Pennsylvania and neighboring regions of the Northeast Thursday
night into Friday...The active November weather pattern impacting CONUS is forecast to
continue through the end of this week and bring hazardous rain, wind, and
snow for several regions. A significant Pacific storm system and strong
atmospheric river have already started pummeling the West Coast and
Northwest this morning. The very deep low pressure system churning about
300 miles off the coast of Washington is responsible for high winds
impacting much of northern California, Oregon, and Washington. These winds
have already produced numerous power outages, reports of tree damage, and
are expected to create blizzard conditions throughout the Cascades.
Fortunately these winds are expected to gradually subside by midday as the
low pressure system swings away from the region. However, a continuous
plume of ample atmospheric moisture content entering northern California
this morning is forecast to linger through the end of the week and lead to
extreme rainfall totals. Over 10 inches of rainfall across the northern
California coast and inland mountain ranges are likely to increase the
threat of life-threatening flash flooding, rock slides, and debris flows.
As this corridor of heavy rainfall lingers along a stationary boundary
extending into the Pacific Ocean, a separate area of low pressure is
forecast to develop and rapidly strengthen off the Northwest coast on
Friday. This storm will help amplify the atmospheric river streaming into
northern California through Friday morning, exacerbating the flooding
threat. WPC has issued a High Risk (level 4/4) of Excessive Rainfall on
Thursday in order to further highlight this concern. Additionally, another
round of strong winds are anticipated from this second low pressure system
throughout the Northwest to end the week. Residents and visitors residing
or traveling between northern California and Washington are advised to
check road conditions before venturing out, listen to advice from local
officials, review emergency plans, and have multiple ways of receiving
warnings.For the central U.S. the main weather story will be found throughout the
northern Plains as heavy snow and gusty winds create near blizzard
conditions today. These hazardous weather conditions are resulting from a
slow-moving and gradually weakening low pressure system just north of the
Minnesota-North Dakota border. The greatest snowfall amounts are forecast
across North Dakota, eastern South Dakota, and northwest Minnesota, but
with additional totals today generally under 4 inches. Wind impacts should
be more widespread and extend into eastern Montana and Nebraska as maximum
gusts could exceed 60 mph through tonight. This area of low pressure is
anticipated to rapidly weaken tonight and lead to calmer conditions on
Thursday.After an extended period of dry and tranquil weather across the Northeast,
the upper level system exiting the northern Plains today will slide
eastward and produce a chance for heavy precipitation in the form of both
rain and snow. The evolution of surface features over the next few days
are forecast to begin with a developing strong and compact low pressure
system over the Great Lakes today, while a cold front quickly pushes
eastward to the Mid-Atlantic by tonight. Showers and maybe a rumble of
thunder may accompany this cold front as rain possibly mixes with snow
spreading across the Great Lakes. By Thursday, a separate area of low
pressure forming along the aforementioned cold front is expected to deepen
and lift northward into the Northeast, while also leading to a blossoming
precipitation shield. Rain is most likely across New England where warmer
air surges from the Atlantic Ocean, but the higher elevations and area
directly underneath the cold upper low pressure system may see
precipitation fall as heavy snow. Probabilities for at least 4 inches of
snow by Friday night are high (70-90%) across northeast Pennsylvania and
the southern Catskill mountains of New York. Impactful snowfall is also
likely to be experienced throughout the Allegheny mountains of West
Virginia, Maryland, and Pennsylvania through the end of the week due to a
longer duration favorable upslope snow setup. Total snowfall amounts in
these higher elevations could add up to a foot.Elsewhere, high pressure building into the south-central U.S. will create
dry conditions from the lower Mississippi Valley to much of the Plains,
Rockies, and Southwest. The temperature outlook features one final day of
widespread 60s and 70s along the East Coast before a strong cold front
knocks afternoon highs below average through the start of the weekend. The
coldest temperatures when compared to climatology over the next few days
are forecast across the northern Plains (highs in the 20s) and Ohio Valley
(highs in the 30s and 40s).
To get your local forecast plus active alerts and warnings click HERE and enter your city, state or zip code.
Learn about wave patterns HERE.
Then, looking at the world and of course, the U.S. shows here also. Today we are looking at precipitation.
Please click on “Read More” below to access the full Daily Report issued today.
| Notices: What would you like to learn about? Please provide that to me via the comment section at the end of the article. |
Now more detail on the 48-Hour Forecast (It is a 48 to 72 Hour Forecast actually)
Daily weather maps. The Day 1 map updates twice a day and the Day 2 and 3 maps update only once a day. These maps update automatically. But if that does not happen, you can get updates by clicking HERE
TODAY (or late in the day the evening/overnight map will appear) (Key to surface fronts shown on maps and you will then also be able to insert a city name or zip code and get a local NWS forecast).
TOMORROW
NEXT DAY
We have a new animation of the forecast which shows how things may play out over the next 60 hours. To update click ANIMATION. Doing so will get you to the dashboard. You can then step through the animation or hit LOOP on the upper right of the display. You will have to hit the back arrow ← at the top left on your computer to get back into this article. It is a little more trouble than before but I think NOAA scrapped the animation routine I was using so we have to keep up with “progress”.
The NWS Climate Prediction Center’s: Watches, Warnings, and Advisories plus other information can be found HERE. That takes you to the NWC Severe Weather Site. From there you can select among many categories of information. Remember to hit the back arrow ← at the top left of your screen to return to this article.
ATMOSPHERIC RIVERS
This tells us what is approaching the West Coast. Click HERE to update If I have not gotten around to doing the update. Here is some useful information about Atmospheric Rivers.
Below is the current five-day cumulative forecast of precipitation (Updates can be found HERE)
Ski SnowReports will Resume in the Fall.
Now we look at Intermediate-Term “Outlook” maps for three time periods. Days 6 – 10, Days 8 – 14, and Weeks 3 and 4. An outlook differs from a forecast based on how NOAA uses these terms in that an “outlook” presents information as deviation from normal and the likelihood of these deviations.
Below are the links to obtain updates and additional information. They are particularly useful if you happen to be reading this article significantly later than when it was published. I always try to provide readers with the source of the information in my articles. These links may also be useful for those viewing this article on a cell phone or other small screen.
| Days 6 – 10 (shown in Row 1) | Days 8 – 14 (Shown in Row 2) | Weeks 3 and 4 (Shown in Row 3 but updates only on Fridays) |
| https://www.cpc.ncep.noaa. gov/products/predictions/610day/ | https://www.cpc.ncep .noaa.gov/products/predictions/814day/ | https://www.cpc.ncep.noaa.gov/products/predictions/WK34/ |
Showing the actual maps. They should now update automatically. The Week 3 – 4 Outlook only updates on Fridays. So below is what I call the Intermediate-term outlook. On Fridays, it extends out 28 Days. That declines day by day so on Thursday it only looks out 22 days until the next day when the Week 3 – 4 Outlook is updated and this extends the outlook by one additional week.
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HAZARDS OUTLOOKS
Click here for the latest complete Day 3 -7 Hazards forecast which updates only on weekdays. Once a week probably Monday or Tuesday I will update the images. I provided the link for readers to get daily updates on weekdays. Use your own judgment to decide if you need to update these images. I update almost all the images Friday Night for the weekend edition of this Weather Report. So normally readers do not need to update these images but if the weather is changing quickly you may want to.
Temperature month to date can be found at https://hprcc.unl.edu/products/maps/acis/MonthTDeptUS.png
Precipitation month to date can be found at https://hprcc.unl.edu/products/maps/acis /MonthPNormUS.png
World Forecast [that website is has been intermittent so be patient]
Below are the Day 1 -3 and 4-6 forecasts for temperature and precipitation. Updates and much additional information can be obtained HERE
World Temperature Anomalies
World Accumulated Precipitation
This information is provided by the University of Maine. They draw upon many different sources. There is a lot of information available at the link provided. I have just provided two useful forecasts. There are probably over a hundred different forecasts available from this source.
Worldwide Tropical Forecast (This is a NOAA Product)
This graphic updates on Tuesdays) If it has not been updated, you can get the update by clicking here Readers will only have to do that if they are reading this article much later than the date of it being published.
Information on Tropical Storms can be found HERE. Western Pacific information can be found HERE. Note that unless there is an out-of-season storm the below images will not update until the National Hurricane Center starts their seasonal update of these maps on June 1. I include them simply because there can be an out-of-season event in which case it should show up in these maps.
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| I hope you found this article interesting and useful. |
