Early Fall Guess (outlook)
The ocean temperature forecast for Autumn from NMME shows that a La Niña anomaly is present. It is not as strong as some from past years, but it is strong enough to impact both the ocean and the atmosphere. Knowing that we should have an active La Niña event again, what did its seasonal influence look like in the past?
For the Autumn 2024 early forecast, the focus is on the two main (or most used) seasonal models: The ECMWF model from Europe and the NMME, which is a combined forecast from several different North American models. The ECMWF model is regarded as one of the most reliable long-range forecast models. But no long-range/seasonal forecast can ever be deemed “reliable”. So only look ECMWF at trends and how weather patterns might evolve on a large scale.
Early autumn ECMWF long range guess for the United States. Over the United States, the core of the warmer temperatures are in the west, under a high-pressure system. Warm anomalies also extend into the eastern United States and eastern Canada. But the far NW areas in United States and western Canada remain in a neutral area.
Looking at precipitation, there could be wetter conditions over the northwestern United States, upper Midwest, east coast, the northeastern United States, and eastern Canada. Less precipitation than normal is forecast over the southern half of the United States under the influence of a broad high-pressure system.
The NMME long range guess. For North America, the temperature forecast shows a warmer Autumn over the western and southwestern parts of the United States. Parts of the Midwest, the eastern United States, and the Northeast all show normal temperatures.
The precipitation forecast for North America shows a very “diluted” forecast due to many models in the mix. But the trends are visible, with less precipitation over the southern United States and parts of the Midwest, with more precipitation likely over the northwest and the east coast.
The official H/L yesterday at Grand Rapids was 81/57 there was no rainfall. The sun was out 87% of the possible time. The highest wind was 14MPH out of the SE. For today the average H/L is 83/63 the record high of 101 was set in 1916 the coldest high of 68 was set in 1915. The record low of 47 was set in 1977 the warmest low of 77 was set in 1916. The wettest was 3.49” in 2011.
The July 2024 mean so far at Grand Rapids is 70.8 that is a departure from average of -2.0° The highest so far has been just 86 if that holds to the end of the month it will be the coldest maximum for any July since 2000 and the 3rd coldest maximum for any July at Grand Rapids. The low for the month is 47 there has been 5.56” of rainfall that is a departure of +2.32”.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
254 AM EDT SAT JUL 27 2024
KEY MESSAGES
- INCREASING HEAT AND HUMIDITY INTO SUNDAY AFTERNOON
- POTENTIAL FOR SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY
DISCUSSION
ISSUED AT 254 AM EDT SAT JUL 27 2024
- INCREASING HEAT AND HUMIDITY INTO SUNDAY AFTERNOON
A MID LEVEL RIDGE AND SURFACE HIGH PRESSURE REMAIN ROOTED OVER THE
STATE THROUGH A GOOD CHUNK OF THE WEEKEND. DRY AND STABLE AIR WILL
RESULT IN TYPICAL MID-SUMMER WEATHER CONDITIONS INCLUDING CLOUD FREE
SKIES WITH RELATIVELY LIGHT WINDS. TEMPERATURES IN THE LOW TO MID
80S TODAY, THEN THE HEAT TURNS ON SUNDAY WITH HIGHS IN THE UPPER
80S. SOUTHERLY RETURN FLOW USHERS IN MOISTURE SUNDAY AFTERNOON
INCREASING HUMIDITY LEVELS LATER IN THE DAY. RAIN CHANCES INCREASE
FOR FAR SOUTHWEST LOWER MI LATE SUNDAY.
- POTENTIAL FOR SHOWERS AND THUNDERSTORMS MONDAY AND TUESDAY
THE MID TO UPPER LEVEL WAVE OF LOW PRESSURE DOWN IN TX LIFTS UP INTO
THE GREAT LAKES REGION MONDAY. WHILE THIS SYSTEM LIFTS NORTHEAST OF
THE AREA ON TUESDAY, ANOTHER WAVE DIGS IN FROM THE NORTHWEST
TUESDAY. INSTABILITY PEAKS IN THE AFTERNOON BOTH DAYS, ESPECIALLY
INLAND. ENSEMBLE PWAT VALUES HAVE TRENDED UP DURING THIS TIMEFRAME
WITH MEAN VALUES IN THE 1.75 TO 2.00 INCH RANGE. THE 0-6KM BULK
SHEAR VALUES REMAIN RELATIVELY LOW SO ORGANIZED SEVERE WEATHER LOOKS
UNLIKELY. THE MAIN IMPACT FROM THE MAINLY AFTERNOON EVENING
CONVECTION WILL BE FOR LOCALLY HEAVY RAINFALL. WE WILL CONTINUE TO
HIGHLIGHT BOTH DAYS WITH HIGH AFTERNOON/EVENING POPS FOR INLAND
LOCATIONS. WPC DOES HAVE THE REGION IN THE DAY 4(TUESDAY) EXCESSIVE
RAINFALL OUTLOOK WITH A MARGINAL RISK.
BEYOND TUESDAY THERE'S STILL A DECENT AMOUNT OF UNCERTAINTY IN TERMS
OF HOW MUCH SHOWER/STORM ACTIVITY WE WILL SEE. THE ECMWF IS SHOWING
A MID LEVEL LOW TRYING TO CUT OFF AS IT DROPS IN FROM THE NORTHWEST
TOWARDS FRIDAY. THE CANADIAN AND GFS KEEP MOVING THIS SYSTEM ALONG.
PWAT'S REMAIN HIGH AND INSTABILITY PEAKS IN THE AFTERNOON/EVENING
HOURS. THERE IS A LOT OF SPREAD IN ENSEMBLE QPF VALUES FOR THE END
OF THE WEEK. FOR NOW WE WILL FEATURE TYPICAL ISOLATED/SCATTERED
AFTERNOON CONVECTION FOR THE REGION.
Detailed Forecast for Grand Rapids
Today
Sunny, with a high near 86. Calm wind becoming south southeast around 6 mph in the afternoon.
Tonight
Mostly clear, with a low around 61. South southeast wind around 5 mph becoming calm in the evening.
Sunday
Mostly sunny, with a high near 89. South wind 3 to 6 mph.
Sunday Night
A 30 percent chance of showers and thunderstorms, mainly after 2am. Mostly cloudy, with a low around 69. South wind 3 to 5 mph.
Monday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 85. South southwest wind 5 to 7 mph.
Monday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 69. Chance of precipitation is 50%.
Tuesday
A chance of showers, with thunderstorms also possible after 8am. Partly sunny, with a high near 85. Chance of precipitation is 40%.
Tuesday Night
A chance of showers and thunderstorms. Mostly clear, with a low around 67.
Wednesday
Sunny, with a high near 88.
Wednesday Night
Partly cloudy, with a low around 68.
Thursday
A chance of showers. Partly sunny, with a high near 88.
Thursday Night
A chance of showers. Partly cloudy, with a low around 69.
Friday
A chance of showers. Partly sunny, with a high near 85.
925pm and the sun is down days are getting shorter fast sofar Summer 2024 has been a breeze in the heat dept let’s keep it going through August then it’s September! LET’S GOO! INDY
So if I’m understanding this outlook correctly, it appears that autumn will be a continuation of the pattern we have been in.
The ECMWF gives our area about a 40 to 60% chance of a warner fall with near average rainfall. It hints at turning to colder as we head into winter. The NMME has our area above to near average in temperature and drier for the fall season. And the NOAA guess is for warmer temperatures and near average rainfall. The NOAA long range guess like the ECMWF has our area trending colder and wetter as we head into the winter season. We shall see.
Slim
No 90’s in July? Will that change on Wednesday 7/31? So much for a hot summer! Bring back upper 70’s and low dew points! Who in their right
mind would want 90’s? Incredible!
July this year has been fantastic!
About one more solid month of meteorological summer before we start slipping into the beautiful fall season.
Other than that on heatwave, this has been an amazing summer so far. Mosquitoes were held at bay until Beryl woke them up. It just may be a coincidence that they came to life following the extra tropical system came through, but the timing was right.
Here is the official NOAA long range guess for meteorological fall.
https://www.cpc.ncep.noaa.gov/products/predictions/long_range/seasonal.php?lead=2
Slim