Updated at 3:52 p.m. EDT Thursday, April 20, 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
345 PM EDT Thu Apr 20 2023Valid 00Z Fri Apr 21 2023 – 00Z Sun Apr 23 2023
…Showers and thunderstorms continue eastward along a cold front from the
Mississippi Valley to the East Coast with isolated flash flooding and
severe weather possible……Moderate to locally heavy snow will continue into the day Friday for
portions of the Northern Plains/Upper Midwest……Precipitation chances increase for the Northern/Central Rockies and
Pacific Northwest Friday; tranquil conditions for California and the
Southwest…
| 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.
Recent;y, we published the Updated ENSO Outlook with the new Alert Status of El Nino Watch. You can access it HERE. We also recently provided an update for the Colorado River Basin with a focus on Spring and Summer stream flow. 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. 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)
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.
A frontal system pushing eastward beneath a deepening upper-level low will
continue to bring widespread showers and thunderstorms with the risk of
flash flooding and severe weather from portions of the Ohio/Mississippi
Valleys Friday to the East Coast on Saturday. There is a Sight Risk of
Excessive Rainfall (level 2/4) for portions of the Lower Mississippi and
Tennessee Valleys Friday where access to deeper Gulf moisture will promote
locally heavier rain rates and 2-3″+ rainfall totals. The slow progression
of the cold front will lead to some repeated rounds of storms over areas
that saw rain Thursday, leading to the risk for some scattered instances
of flash flooding. Moderate to locally heavy rainfall will move eastward
on Saturday through the Appalachians and to the East Coast, though the
risk for any flooding should decrease as the front speeds up and overal
totals trend lower. However, the Storm Prediction Center has issued a
Slight Risk (level 2/5) of severe weather for portions of the coastal
Carolinas as moderate CAPE and deep-layer shear ahead of the cold front
will lead to a line of storms with the potential to produce severe hail
and damaging winds. High temperatures will generally remain in the 80s for
much of the East Friday, with some record-tying/breaking highs in the
upper 80s to low 90s possible for the Mid-Atlantic. Increased
precipitation chances as the cold front approaches on Saturday will drop
temperatures into the 70s for the Mid-Atlantic. New England will remain
cooler on the north side of a stationary front with highs in the 50s and
60s.Moderate to locally heavy snow will continue Thursday evening into early
Friday over portions of the Northern Plains/Upper Midwest on the northwest
side of the low pressure/frontal system. The snow should begin to taper
off by later Friday evening/early Saturday, with storm total snowfall
generally between 3-6″, locally as high as a foot. Gusty winds will also
lead to areas of blowing snow and dangerous travel conditions. High
temperatures will remain quite chilly and much below average behind the
cold front and under the influence of the upper-level low, with highs in
the 30s and 40s for the Northern Plains/Upper Midwest Friday spreading
into the Great Lakes and portions of the Upper/Middle Mississippi Valley
on Saturday. Highs from the Central Plains to the Lower Ohio Valley will
drop from the 60s Friday into the 50s on Saturday.Further south, ongoing showers and thunderstorms in eastern Texas will end
by Friday evening as the cold front pushes off the Gulf Coast. Conditions
across the Southern Plains will turn cooler with highs generally in the
60s and 70s Friday and Saturday outside of the Rio Grande Valley. Morning
lows for portions of the Texas Panhandle and Oklahoma will dip as low as
the upper 30s. Gusty winds mixing down over the Southern High Plains
combined with low relative humidity and dry antecedent conditions have
prompted a Critical Risk for Fire Weather (level 2/3) from the Storm
Prediction Center Friday.Upper-level shortwave energy passing over the Intermountain West will
trigger snow showers for portions of the Northern and Central Rockies
Friday. Some locally heavy accumulating snow will be possible for higher
mountain elevations, particularly in the Central Rockies. A Pacific storm
system will approach the Pacific Northwest later Thursday evening
increasing chances for light to moderate lower elevation coastal/valley
rain and higher elevation snow here as well. Highs will remain cool for
the Northern/Central Rockies following the passage of a cold front and on
the western edge of the expansive upper-level low, with highs generally in
the 40s and 50s. An upper-level ridge building off the Pacific Coast will
lead to tranquil conditions and near-average temperatures for California,
the southern Great Basin, and the Desert Southwest. Highs Friday and
Saturday will range between the 70s and 80s for most of California and the
Great Basin with 90s in the Desert Southwest.
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
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.
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| I hope you found this article interesting and useful. |
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