Updated at 4:06 p.m. EDT Tuesday, April 18, 2023
Here is what we are paying attention to in the next 48 to 72 hours. The article also includes weather maps for longer-term outlooks and a five-day World weather forecast.
We start with the U.S. Information.
Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
227 PM EDT Tue Apr 18 2023Valid 00Z Wed Apr 19 2023 – 00Z Fri Apr 21 2023
…Snow over the Northern Rockies on Tuesday and Wednesday; moderate snow
over parts of the Northern Plains on Wednesday...…Critical Fire Weather will continue through Thursday across the
Southern High Plains as well as across the Mid-Atlantic Tuesday……There is a Slight Risk of severe thunderstorms over parts of the
Central/Southern Plains into the Middle Mississippi Valley on Wednesday……There is a Marginal Risk of excessive rainfall over parts of the
Central Plains, Lower Missouri and Upper Mississippi Valleys on
Wednesday…
| Information Note: This article is now set up so that all the maps should automatically update. The links are provided but should not be needed. The downside is that if you go back to a previous version the maps will have been updated and not be relevant to the date of the prior article but will be current information. The NWS twice-a-day 48-hour forecasts do not auto-update in this article. I do it and I can be late doing it. The link for the NWS updates is HERE. Most of our other articles will not be set up to auto-update so that prior versions of the article will be meaningful.
Last night we published the Updated ENSO Outlook with the new Alert Status of El Nino Watch. You can access it HERE. Remember the easiest way to get back to the article you were reading is to hit the return arrow in the upper left of your screen. There are other ways. |
First, the 48-Hour Forecast (It is a 48 to 72 Hour Forecast actually)
Daily weather maps. I try to keep the below three maps updated. The Day 1 map updates twice a day and the Day 2 and 3 maps update only once a day. I will be doing the updating during the period described in the title of the article but if you happen to read this article later, you can get updates by clicking HERE
TODAY (or late in the day the evening/overnight map will appear)
TOMORROW
NEXT DAY
This animation shows how things may play out over the next 60 hours. To update click here.
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.
Continuation of the NWS Short Range Forecast. It is updated by NWS twice a day and these updates can be found here. We post at least one of those updates daily, sometimes both. The Highlights are shown in the lede paragraph of this article.
For the remainder of Tuesday, an upper-level wave will continue to track
through the northern Intermountain West supporting some moderate snowfall
across the Northern Rockies this evening. Concurrently, a surface low
near the Black Hills of SD and portions of E MT/WY will start to
strengthen and merge with the associated Pacific cold front, lifting a
warm front northward across the central Plains sparking the potential for
a few isolated severe thunderstorms. The Storm Predication Center (SPC)
has a broad Marginal Risk in the vicinity of the low and southward into
the central High Plains just ahead of a strengthening dry line. Further
south, the strengthening winds and very dry ground conditions will
continue to support a broad Critical Fire Weather area issued by SPC, with
a large area of New Mexico, Eastern Colorado, Western Nebraska, Western
Kansas and parts of the OK/TX panhandles already under Red Flag Warnings.
This risk will continue as the strong Pacific flow over-topping the
Central Rockies will keep winds and relative humidity low through Wed into
Thursday as well.Into the overnight period (Tues into Wednesday), the surface low will
continue to lift north, strengthen and have the potential for producing
moderate to occasionally heavy snow fall across far eastern MT, and
western/northwestern North Dakota, peaking Wednesday morning, but likely
to continue throughout the remainder of the day into early Thursday
morning.As the main upper-level energy emerges into the northern Plains on Wed,
the risk for severe weather increases in coverage/intensity, as the SPC
has issued a Slight Risk along/ahead of the cold front and dry line from
eastern Nebraska into Iowa and southward across central/eastern Kansas
into western Oklahoma. Large hail and high winds are the greatest
potential, though an isolated tornado or two remain possible, with highest
potential across central Kansas. As the thunderstorms expand in coverage
into the early overnight period, thunderstorms will pose a risk of
excessive rainfall/flash flooding mainly north and east of the SPC Slight
Risk, given areas of Iowa, southeast Minnesota, Wisconsin soils more
saturated and have seen recent snow melt. As such, the Weather Prediction
Center (WPC) has issued a broad Marginal Risk to account for heavy
rainfall over these saturated areas resulting in isolated to widely
scattered flash flooding potential into Thursday morning.Elsewhere, a very broad large scale low dominates southeast Canada
resulting in large area of increased cloud cover across the Northeast,
keeping temperatures at or below average today into tomorrow. South of
the cloud area in the Mid-Atlantic, clearer skies and drier air (along
with drier than normal soils/vegetation) will see increased temperatures
in the 70s and 80s into Wednesday. The combination has resulted in
increased fire weather concerns, with the SPC issuing a Critical Fire area
across the Piedmont of Virginia with a surrounding Elevated Risk over the
remainder of the state and portions of adjacent Maryland, West Virginia,
Delaware and far northeast North Carolina. Red Flag Warnings are up for
much of the Elevated area for today, Tuesday.
Below is the current five-day cumulative forecast of precipitation (Updates can be found HERE)
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.
| 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
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| 8
– 14 |
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| 3
– 4 |
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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.
Month to Date Information
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 [This is not updating – I will attempt to fix it very soon – It looks like the source changed what they published from Day 1- 5 to day 4 – 6. If this updates I will add the Day 1 – 3 graphic to the article]
Below are the 4-6 Day forecasts for temperature and precipitation. Updates and much additional information can be obtained HERE
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.
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| I hope you found this article interesting and useful. |
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