Winter forecast, part III: the Old Farmer's Almanac

By: Dr. Jeff Masters , 2:23 PM GMT on November 24, 2008

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Since 1792, the Old Farmer's Almanac has been issuing long-range seasonal weather forecasts. This year, the Almanac is predicting that winter will be colder than average for 3/4 of the U.S., and above average over just 1/8 of the country. Only the Pacific Northwest and the upper Midwest near Minnesota are predicted to be warmer than average. For the Appalachian region that includes the three woolly bear forecasts I discussed last week, the Old Farmer's Almanac is siding with Oil Valley Vick and Kelly the woolly bear, forecasting colder than average temperatures. The Hagerstown Woolly Bears and NOAA disagree, predicting warmer than average temperatures are more likely.

How accurate is the Old Farmer's Almanac?
The Old Farmer's Almanac claims to have a secret formula developed in 1792 based on sunspots and climatology, which gives their long-range predictions 80% accuracy. I've heard a number of anecdotal stories about how uncannily accurate their forecasts are, and have always felt a vague sort of anxiety that maybe I should be checking them out when someone asks me what the upcoming winter will be like. However, the Almanac does not post any verification statistics of their forecasts. It is not hard to do a simple check of their forecast accuracy, though. Unfortunately, the results of my check and those done by several others show that there is little reason to believe that the Old Farmer's Almanac forecasts are any better than flipping a coin.


Figure 1. Observed departure of temperature from average for the period Nov. 2004-Mar. 2005. Superimposed in bold text is the winter forecast made in the 2004 Old Farmer's Almanac for the same period. The Almanac got four regions correct and eight incorrect, with two too close to call.

For example, for the winter of 2004-2005 (Figure 1), the November 2004 version of the Old Farmer's Almanac made a simple prediction of "cold" or "mild" for sixteen separate regions of the U.S. The original forecast map they presented only labels the U.S. in fourteen places, and I've overlaid these predictions on a temperature anomaly map showing what actually happened during the winter of 2004-2005. If we assume that "mild" refers to an above average temperature forecast and "cold" refers to a below average temperature forecast, then the Almanac got four regions correct, eight wrong, with two too close to call. Admittedly, I've "eyeballed" this, and it is a subjective verification. Still, I don't see any way that this forecast could approach even 50% (chance) accuracy. Their precipitation forecast fared better, with seven correct regions, five incorrect, and two too close to call. I also looked at the Farmer's Almanac forecasts for the winter of 2006-2007. They did much worse that winter, with only three of sixteen temperature forecasts verifying, and five out of twelve precipitation forecasts verifying (four were too close to call). For these two winters, the Old Farmer's Almanac made a successful forecast just 37% of the time.

Studies by Jan Null
Jan Null, a meteorologist who founded the private weather consulting firm, Golden Gate Weather in California, has evaluated the Old Farmer's Almanac predictions for San Francisco for three separate years. His first study looked at the forecasts for 1999-2000. His conclusion: "Even trying to be objective and giving the benefit of the doubt to cases that were close, I found last year's forecast from the Old Farmer's 2000 Almanac for San Francisco to be laughable at best and abysmal at worst. The Old Farmer's Almanac was wrong on their monthly temperature forecast 8 out of the 12 months (67%) and wrong on their rainfall forecast 5 of the 8 months evaluated (63%)". His grade for the Old Farmer's Almanac winter forecast for San Francisco during 2006-2007 was a D+. He also evaluated the Old Farmer's Almanac for two separate summers and winters for all sixteen regions of the U.S., and found mostly poor results. For the summer of 2005, just one of the sixteen Old Farmer's Almanac regional forecasts got both the temperature and the precipitation correct. He plans to post a verification of their 2008 summer forecast sometime in the next week.

Weatherwise magazine study
In the October 1981 issue of Weatherwise magazine, pages 212-215, John E. Walsh and David Allen performed a check on the accuracy of 60 monthly forecasts of temperature and precipitation from the Old Farmer's Almanac at 32 stations in the U.S. They found that 50.7% of the monthly temperature forecasts and 51.9% of the precipitation forecasts verified with the correct sign. This compares with the 50% success rate expected by chance.

Old Farmer's Almanac climate forecast
It's also of interest to note that the Old Farmer's Almanac believes that sunspot cycles and other factors suggest that "a cold, not warm climate may be in our future". Their climate forecaster is Joeseph D'Aleo, who was the first Director of Meteorology at the Weather Channel. Mr. D'Aleo is now retired, and is often quoted for his skeptical opinions about climate change.

Conclusion
The results of my forecast verifications and those done by several others indicate that there is little reason to believe the Old Farmer's Almanac claim of 80% accuracy. These verifications attempted to be fair, but one can justifiably argue they were not objective nor complete. However, unless the Almanac posts some scientific evidence to the contrary, I won't believe their forecasts are any better than flipping a coin. One's best bet for the upcoming winter forecast is to use NOAA's prediction, which calls for an an above-average chance of a warm winter across the center portion of the U.S. If you live in Banner Elk, North Carolina, it might be wise to go with Kelly the Woolly worm's forecast of a cold winter, though, given the success of her predecessors!

Tropical disturbance near Costa Rica
An area of disturbed weather (96L) has developed in the extreme southern Caribbean, near the coast of Costa Rica. Wind shear is a hefty 20-30 knots over the disturbance, which will keep any development slow. The disturbance will bring heavy rains to Costa Rica and Nicaragua through Wednesday. If the center can stay off shore, this disturbance has the potential to develop into a tropical depression. NHC is giving a moderate (20-50% chance) that 96L will develop into a tropical depression by Wednesday morning. The GFDL model does develop 96L, but none of the other models do. I'll have an update on the system this afternoon if it gets more organized.

Jeff Masters

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NEXRAD Radar
New Orleans, Base Reflectivity 0.50 Degree Elevation Range 124 NMI,..Squall Line associated withthe Frontal Boundary Link
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I understand that Granny on The Beverly Hillbillies had a "Weather Beetle" that was accurate 100% of the time. Maybe we should consult her beetle if he's still around.
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96L floater
Member Since: July 12, 2007 Posts: 0 Comments: 6049
119. HadesGodWyvern (Mod)
Magnitude 7.3
Date-Time Monday, November 24, 2008 at 09:02:58 UTC
Monday, November 24, 2008 at 08:02:58 PM at epicenter
Time of Earthquake in other Time Zones

Location 54.198°N, 154.316°E
Depth 491.7 km (305.5 miles)
Region SEA OF OKHOTSK
Distances
Member Since: May 24, 2006 Posts: 51 Comments: 45622
118. HadesGodWyvern (Mod)
RSMC: India Meteorological Department

Tropical Cyclone Outlook - 0900z 24NOV
=========================================
This morning's low pressure area over Sri Lanks and neighborhood now lies as a well marked low pressure area over the same region. The interpretation of numerial weather prediction models indicate that the system is likely to concentrate into a depression over southwest Bay of Bengal and further intensify into a tropical cyclone during subsequent 48 hours.
Member Since: May 24, 2006 Posts: 51 Comments: 45622
Just ran across a ship reading from 11.2N/76W of 1004mb.
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Budget changes here... VAT actually gone down to 15% although other rises are included... quite the gamble. Borrowing to increase. Basically, may sort us out now but in ten or so years time I would not want to be here. There will be an almighty tax bombshell. States, here I come...

In European Markets...

FTSE up by 9.84%
Dax and Cac 40 both up by over 10%

Not too bad, not too bad at all.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Had to open my big mouth... some last minute profit taking... but looks to be rebounding in the last few minutes here...

Still, very nice, right now about +12% over past two sessions.
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Moved significantly NW (to new SSD position) and increased to 1008mb at 18Z:

Link

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i updated my blog this morning if anyone would like to review......

TampaSpins Weather Blog Link
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Decreasing but shear is still eating it especially on its north side.
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting IKE:


I'm surprised it's at 1.5 for a T #....looks stretched out..and less defined. Suppose it's getting sheared.


And that's putting it gently. ;)
Member Since: August 23, 2008 Posts: 7 Comments: 5300
Quoting IKE:


I'm surprised it's at 1.5 for a T #....looks stretched out..and less defined. Suppose it's getting sheared.


Its indeed being sheared at the present time...I see nothing at the surface with this feature.Slim chances at any signficant development.
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And, IKE, now we're hummin'. :)

DJIA
8,563.97
+517.55
+6.43%
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IKE - yeah, and unchanged from when it was orange. I think the change to yellow (before current presentation) because of shear and that if it keeps moving W at that speed/repositioning, it will be over land before it can get going.
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Just updated......

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Quoting Seastep:
Good afternoon Tampa.

Thanks for the tunes.


Your welcome.....music sooths the beast in us all.....LOL
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Severe weather breaking out in Mississippi...

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104. IKE
Quoting Seastep:
DATE/TIME LAT LON CLASSIFICATION STORM
24/1745 UTC 11.4N 82.3W T1.5/1.5 96L
24/1145 UTC 11.4N 81.9W T1.5/1.5 96L


I'm surprised it's at 1.5 for a T #....looks stretched out..and less defined. Suppose it's getting sheared.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
ok...gotta bounce...peewee still sleeping from nap...if I don't get him up...he won't sleep tonight...bbl if I can....
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hey tampa
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Good afternoon Tampa.

Thanks for the tunes.
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Good afternoon everyone.
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DATE/TIME LAT LON CLASSIFICATION STORM
24/1745 UTC 11.4N 82.3W T1.5/1.5 96L
24/1145 UTC 11.4N 81.9W T1.5/1.5 96L
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92. hurricanemaniac123

I think it is two reasons.

1. Shear
2. Keep repositioning it farther W and if that is, in fact, the center, then it will be over Nicaragua or CR before it has time to develop into anything.
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looks like NE may get an extra long Thanksgiving break....
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Quoting hurricanemaniac123:
Where is everyone?


Waiting for the NWS to issue winter weather headlines here in the NE! How long must they wait?!
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ok...woolybears, farmers almanac, other sources...why not just go on the acorn theory?
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been lurking...
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Where is everyone?
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I have little understanding to why the NHC downgraded 96L to yellow. It's getting a well-defined surface circulation, it has 30 mph winds, and great convection. I thought it would've been on red at 1pm.
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I have a long write up in my blog today about the storm. I feel as though I covered everything but I could've added in a few more details. Oh well. For the most part the forecast looks good and shouldn't need any changes.

I had my area right under the 3-6/6-12" line in the snowmap and then the 12Z guidance came in and backed my forecast up. I was worried looking at the 00/06Z model suite from last night thinking this one might go warm here but instead if flipped back to the cold side of things. Saves me a lot of time having to write up a new blog to cover a changed forecast, tha's for sure.
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85. IKE

While Citi certainly had an impact and the simple fact of knowing who the team is lessens uncertainly (market hates uncertainty), IMO, it is actually that there are hints that Obama will NOT do what he said he was going to do during the campaign that is helping the most. Indications that he will delay any tax increases for two years.

i.e., it's the fact that he will NOT do what he said he would do that is helping the most.

Have to give him credit for that, though. Just wish it wasn't "hints" and he came out and made a promise.

Just wish he would come out and state that he will not be raising capital gains as he promised. Otherwise, we ain't seen nothing yet as we approach the end of the year and people want to be taxed at the current rate vs. the higher rate.

JMO.
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were expecting the warm side here in eastern mass.temps may shoot into the 50/s tomorrow afternoon with 30-40mph winds and possible thunder,you get the cold side
Member Since: September 6, 2007 Posts: 881 Comments: 15840
12Z ECMWF just rolling in and shows a really big storm early next week coming up the Eastern Seaboard followed by an arctic blast and a potent clipper.

Looking VERY snowy here in the NE...
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Quoting NEwxguy:
sulli,are you expecting any snow out of this system tomorrow


At least 5". I don't know why BGM hasn't issued any headlines for my area yet. I know they hinted at waiting on the 12Z guidance before raising flags but now that it has come in (colder and snowier than the 00Z model suite) I'm expecting something to be issued any minute.

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sulli,are you expecting any snow out of this system tomorrow
Member Since: September 6, 2007 Posts: 881 Comments: 15840
85. IKE
Obama paying off already...

From CNN....

Stocks surge on Citi, Obama
The government rescue of the ailing bank and the President-elect's pick for his economic team propel stocks.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
Quoting IKE:
154 hours
59 minutes....

and the 2008 Atlantic hurricane season is history.


Could be wrong...

Member Since: August 23, 2008 Posts: 7 Comments: 5300
83. IKE
154 hours
58 minutes....

and the 2008 Atlantic hurricane season is history.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
The ISS is going to flying directly over my house tonight (88°) but the clouds are going to prevent me from seeing it.
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You're going to run into some trouble traveling over the Appalachians tomorrow. A cold front blasting through the region tonight is going to bring a moist upslope flow to the region resulting in several inches of heavy wet snow. Be prepared for that along with some gusty winds.
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re 73
Actually the satellite image looked a lot healthier 3 hours ago. It has now become very ragged again.
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Hey folks! I have family making a long car-trek from Des Moines to Charleston, SC today and tomorrow. From Tampaspin's radar map above it looks like today's journey will be clear. Any predictions on what that front along the Smokies will be doing tomorrow? TIA.
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Hi JP,
Any thoughts on 96L?
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96L abysmal
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Quoting stormpetrol:
WOW! This is best IMO that 96L has looked and its been placed back in yellow, The NHC must have read my comment#70 :)


Don't put too much emphasis on a satellite imagery. There are more factors than that that come into play to determine tropical cyclogenesis.
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just as I thought...down to yellow..


TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
100 PM EST MON NOV 24 2008

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

A LARGE AREA OF DISTURBED WEATHER CONTINUES OVER THE SOUTHWESTERN
CARIBBEAN SEA ASSOCIATED WITH A BROAD AREA OF LOW PRESSURE. THERE
ARE NO SIGNS OF TROPICAL CYCLONE FORMATION AT THIS TIME AND FURTHER
DEVELOPMENT...IF ANY...IS EXPECTED TO BE SLOW. THIS SYSTEM WILL
LIKELY PRODUCE HEAVY RAINS AND LOCALIZED FLOODING OVER PORTIONS OF
PANAMA...COSTA RICA...AND NICARAGUA DURING THE NEXT COUPLE OF DAYS.



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WOW! This is best IMO that 96L has looked and its been placed back in yellow, The NHC must have read my comment#70 :)
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When I lived in Northeastern NJ many years ago I did my own review of the Almanc's forecasts and came up with a less than 30% hit that one year. Darts worked just as well.
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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

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