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 Dec 18 2024
Valid 12Z Wed Dec 18 2024 – 12Z Fri Dec 20 2024…Clipper system to bring periods of moderate to heavy snow and gusty
winds to the northern Plains and Upper Midwest/Great Lakes the next couple
of days……Showers and storms continue into the day Wednesday for the
Ohio/Tennessee Valleys with some locally heavy rainfall and isolated flash
flooding possible……Well above average temperatures continue for much of the lower 48…
Lower elevation/coastal rain and higher elevation snow will linger into
the early morning hours Wednesday over the Pacific Northwest and northern
Great Basin/Rockies as an upper-level wave departs the region. The wave
will then pass over the northern High Plains, leading to lee cyclogenesis
and the organization of a clipper system that will drop east-southeastward
over the Plains and Midwest the next couple of days. Strengthening moist
southerly flow over colder air to the north will bring an intensifying
band of snow to the northern Plains Wednesday evening and into the
overnight hours. Winter Storm Watches have been issued for northern and
eastern North Dakota and northwestern Minnesota where 3-6 inches of snow,
locally higher, can be expected. A wintry mix will be possible to the
south of the heaviest snow with some snow and light ice accretions
possible from eastern Montana southeastward through western North Dakota
and into eastern South Dakota. In addition, very strong, gusty winds are
expected across the northern Rockies and High Plains Wednesday into
Thursday. This will lead to blowing snow and low visibility where snow is
either falling or remains on the ground. The system will pass through the
Upper Midwest/Great Lakes Thursday, bringing some moderate to locally
heavy snowfall, particularly across portions of northern Wisconsin.Showers and thunderstorms continue this morning ahead of a cold front
stretching from the Ohio Valley southwest through the Tennessee/Lower
Mississippi Valleys and into the southern Plains. Some locally heavy
rainfall is expected across the Ohio and Tennessee Valleys where storm
motions more parallel to the slow moving front will lead to a few repeated
rounds of storms. Isolated flash flooding will be possible particularly
across the Tennessee Valley where local soil conditions are more
saturated. The boundary will become more progressive by Wednesday
afternoon and sweep eastward across the Southeast and to the East Coast
into Wednesday evening, with some more isolated storms possible. Moist
flow along a warm front lifting northward ahead of the system will also
bring moderate rainfall to the coastal Northeast as well as the potential
for some accumulating snow for higher elevations of the interior Northeast
Wednesday afternoon through the early morning hours Thursday.
Precipitation should come to an end for all but Florida by Thursday
afternoon as the front pushes into the Atlantic.Elsewhere, thunderstorms remain in the forecast for South Florida
Wednesday with some very heavy downpours and isolated flooding possible
for urban areas. Extreme to Critical Fire Weather conditions have also
been outlined by the Storm Prediction Center in the Los Angeles vicinity
as gusty winds and dry conditions remain in place. Precipitation chances
will return to the Pacific Northwest by Thursday evening as another
Pacific system approaches the region. Much of the lower 48 will continue
to see well above average temperatures over the next couple of days, with
highs running 10-20 degrees above average for the Southeast Wednesday
(60s-70s), the south-central U.S. Thursday (60s-70s), and the West through
Thursday (40s-50s interior, 60s-70s West Coast and Deserts). The Northeast
will be more seasonable with highs in the mid-30s (interior) to low 50s
(coast). One region that will see much colder temperatures will be the
Northern Plains/Upper Midwest, where highs will mainly be in the teens and
20s and gusty winds will lead to even colder wind chills. The northern
High Plains will see some relief Thursday as downsloping winds bring
warmer temperatures.
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
New Feature – Ski Reports. 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 Econcurrents Article and we may add those links. We will try to not have too much overlap as that can add to the confusion.
Snow Forecasts. And remember this shows natural snow. Ski resorts also make their own snow.
Day 1
Day 2
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.
| 6–
10
|
|
|
| 8–
14 |
|
|
| 3–
4 |
|
|
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.
–
| I hope you found this article interesting and useful. |
