Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 8, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Valid 00Z Tue Aug 08 2023 – 00Z Thu Aug 10 2023

…Very active east coast weather late afternoon into early evening Monday
with severe weather, heavy rains and flash flooding possible from the
Mid-Atlantic into the Southeast…

…Heavy rains and a flash flood threat for eastern New York State into
New England Monday evening into Tuesday…

…Heavy rains and a flash flooding threat also from Monday night into
Wednesday across portions of the Central to Southern Plains, Middle to
Lower Mississippi Valley, Lower Ohio and Lower Tennessee Valleys…

…Record heat to continue from the Southern Plains, along the Gulf Coast
and into Florida…

…Elevated fire weather risks to continue for portions of the Great
Basin, Southwest and Southern Plains…

…Cooler than average temperatures expected from the Northern Rockies,
through portions of the Plains, Mid Mississippi Valley, Ohio Valley and
Northeast…

 

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 7, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Mon Aug 07 2023

Valid 00Z Tue Aug 08 2023 – 00Z Thu Aug 10 2023

…Very active east coast weather late afternoon into early evening Monday
with severe weather, heavy rains and flash flooding possible from the
Mid-Atlantic into the Southeast…

…Heavy rains and a flash flood threat for eastern New York State into
New England Monday evening into Tuesday…

…Heavy rains and a flash flooding threat also from Monday night into
Wednesday across portions of the Central to Southern Plains, Middle to
Lower Mississippi Valley, Lower Ohio and Lower Tennessee Valleys…

…Record heat to continue from the Southern Plains, along the Gulf Coast
and into Florida…

…Elevated fire weather risks to continue for portions of the Great
Basin, Southwest and Southern Plains…

…Cooler than average temperatures expected from the Northern Rockies,
through portions of the Plains, Mid Mississippi Valley, Ohio Valley and
Northeast…

 

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 6, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Sat Aug 05 2023

Valid 12Z Sat Aug 05 2023 – 12Z Mon Aug 07 2023

…Dangerous heat will continue for the Desert Southwest, Southern Plains
and Lower Mississippi Valley but relief for some is coming beginning on
Sunday…

…Potential for severe thunderstorms and/or flash flooding from the
central/northern Plains into parts of the Midwest…

 

Is Global Warming Impacting the ENSO Cycle – August 5, 2023

Is Global Warming impacting the ENSO Cycle? A friend of mine posted an interesting post on this on Climate.Gov and I think it is worth discussing. But we really do not have the ability at this point in time to know if this is happening and if so why.

This introduces the ENSO BLOG post on Climate.gov. Here is the link to the full post.

He provides two pieces of evidence. This is the one that resonated with me.

Presumably, we see higher highs (El Nino) and lower lows (La Nina) since 1960.  We do not seem to see higher highs and higher lows which one might expect with warmer oceans but all the values are anomalies that complicate things a lot. Actually, I am not 100% sure of exactly what this data represents. Presumably, it is the 5-month running mean minus the 1981- 2010 climatology. That is slightly different than the usual calculation of the value of the Nino 3.4 Index but it is challenging to compare current values to historical values as the temperature of the ocean surface increases.  I will copy Mike McPhaden and ask him if I have described the above correctly – stay tuned.  Trying to understand the impact of Global Warming is not simple.

The Footnotes to the post provide useful information

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 5, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Sat Aug 05 2023

Valid 12Z Sat Aug 05 2023 – 12Z Mon Aug 07 2023

…Dangerous heat will continue for the Desert Southwest, Southern Plains
and Lower Mississippi Valley but relief for some is coming beginning on
Sunday…

…Potential for severe thunderstorms and/or flash flooding from the
central/northern Plains into parts of the Midwest…

 

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 3, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Thu Aug 03 2023

Valid 12Z Thu Aug 03 2023 – 12Z Sat Aug 05 2023

…There is a Slight Risk of excessive rainfall over parts of the
Ohio/Tennessee/Middle Mississippi Valleys, Southeast and Southern
Appalachians, along with two areas over the Northern/Central Plains into
the Great Basin…

…There is an Enhanced Risk of severe thunderstorms over parts of the
Central High Plains…

…Excessive Heat Warnings and Advisories from parts of Central/Southern
Plains and the Middle/Lower Mississippi Valley/Central Gulf Coast…

 

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 2, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Wed Aug 02 2023

Valid 12Z Wed Aug 02 2023 - 12Z Fri Aug 04 2023

...There is a Moderate Risk of excessive rainfall over parts of the Middle
Mississippi Valley on Wednesday and a Slight Risk over parts of the
Ohio/Tennessee Valleys and Southern Appalachians, along with two areas
over the Northern/Central Plains on Thursday...

...There is a Slight Risk of severe thunderstorms over parts of the Middle
Mississippi Valley on Wednesday and the Central High Plains on Thursday...

...Excessive Heat Warnings and Advisories from parts of Central/Southern
Plains and the Lower Mississippi Valley/Central Gulf Coast...

 

NOAA Updates It’s August, 2023 Outlook on July 31, 2023- There Have Been Some but not Dramatic Changes from the Mid-Month Outlook

At the end of every month, NOAA updates its Outlook for the following month which in this case is August of 2023. We are reporting on that tonight.

There have been some changes in the Outlook for August but they are not dramatic and these are addressed in the NOAA Discussion so it is well worth reading.  We provided the prior Mid-Month Outlook for August for comparison. It is easy to see the changes by comparing the Mid-Month and Updated Maps.

The article includes the Drought Outlook for August. NOAA also adjusted the previously issued Seasonal Drought Outlook to reflect the changes in the August Outlook. We have also included the current fire incidents and a map showing the water-year-to-date precipitation. We also provide the Week 2/3 Tropical Outlook for the World.

The best way to understand the updated outlook for August is to view the maps and read the NOAA discussion. But here are some of the highlights:

  • El Niño conditions are present in observations of the equatorial Pacific atmospheric and ocean, and are likely to continue through the month of August and into later seasons.
  • The updated August temperature outlook favors above normal temperatures across Alaska with more likely above normal temperatures for southeastern Alaska,
  • Above normal temperatures continue to be favored for much of the West, as in the prior outlook. However, probabilities of above normal have decreased substantially across the Great Basin, and there are now equal chances (EC) of above, near or below normal temperatures for much of California,
  • Below normal temperatures are favored for a small area of the northern High Plains,
  • Probabilities of above normal temperatures are further enhanced from the Southern Plains into the Southeast,
  • Average below normal temperatures are slightly favored for parts of the Northeast for the month of August,
  • The updated August precipitation outlook favors below normal precipitation for southwestern areas of the Alaska Mainland eastward along the coast into southeast Alaska,
  • Above normal precipitation is favored in a swath from the northern Rockies across parts of the High Plains, the Central Plains, and Ohio Valley,
  • Above normal precipitation is likely for August, probabilities exceeding 50 percent, for a small area of the northern High Plains,
  • Above normal precipitation is favored for the East Coast from parts of the Carolinas to New England, with much above average sea surface temperatures offshore and the influx of moisture.
  • Below normal precipitation is favored from parts of the Southwest, the Rio Grande Valley, and the Gulf Coast, to the Florida Panhandle,
I am going to start with a graphic that shows the updated Outlook for August followed by a graphic that shows both the Updated Outlook for August and also the three-month outlook ASO 2023. So you get the full picture in two graphics.

Here is the updated Outlook for August 2023

For Comparison Purposes, Here is the Mid-Month Outlook for August.

There has been some change but not dramatic. Remember, it is the top set of maps that are the current outlook for August.

Combination of the Updated Outlook for August and the Three-Month Outlook

The top row is the Updated Outlook for the new month. There is a temperature map and a precipitation map. The second row is a three-month outlook that includes the new month. I think the outlook maps are self-explanatory. What is important to remember is that they show deviations from the current definition of normal which is the period 1991 through 2020.  So this is not a forecast of the absolute value of temperature or precipitation but the change from what is defined as normal or to use the technical term climatology.
Not much difference between August and the three-month period that includes August.  I am too tired to figure it out right now but there is some similarity between the one-month and three-month and the mid-month for August and the updated outlook for August. There is no reason for that but if I am not dreaming it there is some pattern there which I will look at again the next time I am coherent and have the time to do it.

ANALYSIS
Notice that for both temperature and precipitation, the one-month Outlook and three-month Outlook are not similar. This suggests that the Outlook for the combined second and third months if shown would be different than either the Outlook for the First (next) Month or the Three-Month Outlook. The formula for calculating the combined second and third-month outlook is:
For both temperature and precipitation, if you assume the colors in the maps are assigned correctly, it is a simple algebra equation to solve the month two/three anomaly probability for a given location = (3XThree-Month Probability – Month One Probability)/2*. So you can derive the month two/three outlook this way. You can do that calculation easily for where you live or for the entire map.

It is important to remember that the Outlook for next month was updated on the last day of the current month and the three-month Outlook was issued on the third Thursday. So the period of time between the Mid-Month and End of Month Update varies from month to month from 10 days to 16 days. So there sometimes is a substantial change in the Next Month’s Outlook from the Mid-Month prediction.  In such cases, we wonder if a change in the one-month outlook suggests that the three-month outlook would need to also be adjusted. This month I do not think that it is the case.

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted August 1, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Wed Aug 02 2023

Valid 12Z Wed Aug 02 2023 – 12Z Fri Aug 04 2023

…There is a Moderate Risk of excessive rainfall over parts of the Middle
Mississippi Valley on Wednesday and a Slight Risk over parts of the
Ohio/Tennessee Valleys and Southern Appalachians, along with two areas
over the Northern/Central Plains on Thursday…

…There is a Slight Risk of severe thunderstorms over parts of the Middle
Mississippi Valley on Wednesday and the Central High Plains on Thursday…

…Excessive Heat Warnings and Advisories from parts of Central/Southern
Plains and the Lower Mississippi Valley/Central Gulf Coast…

 

Tonight, Tomorrow, Next Day, Five Days, and Intermediate-Term Outlooks for the U.S. and a Six-Day Forecast for the World: posted July 31, 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 outlook.

We start with the U.S. Information. You can update this section here but these are 48 to 72-hour forecasts so if I have not been able to update this area twice daily, what is shown is still valid and the images in the body of the article update automatically but sometimes they are a bit slow to update.

Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
Mon Jul 31 2023

Valid 12Z Mon Jul 31 2023 – 12Z Wed Aug 02 2023

…There is a Slight Risk of excessive rainfall over parts of the Central
High Plains…

…Excessive Heat Warnings and Advisories from parts of Central/Southern
Plains and the Lower Mississippi Valley/Central Gulf Coast…