Tuesday: 2 June 2009
First off:
Starting in June, I’ve taken over from the first CoCoRaHS Oglethorpe County coordinator. It’s a fairly simple job that mostly involves keeping an eye on the eighteen Oglethorpe County stations, answering questions, and such. The most work is involved in publishing the weekly rainfall totals for each reporting station in the local weekly, the Oglethorpe Echo. And that’s that. Onward:
It’s The merry Month of May, Number 40 in a series. This was the third month of relatively normal weather. Others had much more interesting things to talk about.
From the National Weather Service Climate Prediction Center, this is a plot of high and low temperature anomalies for the US. That’s the difference in the average temperature for this May above or below the average for May over many years, plotted in colors. The anomalies are in Fahrenheit.
The northern tier of states from the Pacific to the Great Lakes were unusually cool for at least the third month in a row (and I presume these temperature anomalies extend into Canada as well). Looks like Kansas and some of the surrounding states were a bit cooler than usual. The eastern US was just slightly warmer than usual in most places.
The most remarkable anomalies occurred in the southwest where parts of California, Nevada, Utah, Colorado, Arizona, and New Mexico experienced temperatures 6-8 degF warmer than usual.
The National Weather Service Climate Prediction Center is hiding these precipitation plots here, and that’s where we’ll find the plot of mean precipitation anomalies for the US over the month of May:
Parts of the southwest got a little relief in the form of rain, but much continued to be dry, as has been generally true since November. Pacific states, except for southern California, got a little extra rain. Conditions were somewhat dry throughout the central states. But the real story for the southeast was rain.
After the sixth month of unusually dry conditions Florida got rain with a vengeance, and much of that spread into south Georgia. A few days ago I posted on the odd nature of the couple of weeks of continuously cloudy or wet weather so I won’t go into that so much here. But I also noted that locally we were about an inch below normal - if you look closely at that map you’ll see that there are tiny patches of neutral white amidst all that green. If you look closely enough you might just see a patch of brown hanging over our house!
For Athens:
It only seemed cooler here than it should be - it really wasn’t, so memory doesn’t always serve.
Here is my plot of high temperatures for the month of May in Athens. (It seemed appropriate to present high temperatures this time.) As usual, the black dots are for the 18 years 1990-2007 (black dots), 2009 (green line), and 2008 (red line).
We almost broke a low on a couple of nights around May 20, and never approached record highs. Nonetheless our average temperature in May was 70.5 degF, compared to 70.0 over many years.
We had NO days that were more than one standard deviation above the mean high daily temperatures, and only two nights more than one standard deviation below the average. That’s so average it’s almost painful.
For rainfall, the figure below shows the Athens data which are official for our area. As usual the green line shows our actual rainfall, the red shows the average accumulation expected. The black dots are rainfall over the last 19 years, the vast river of peach shows the standard deviation. We were above average for most of the month, and then officially ended right at about the average. That figure doesn’t quite display it properly, mainly because the red line average isn’t where it should be, at 3.86 inches. That average is over many years whereas my day to day average is only since 1990. The average rainfall of 3.0 inches you see there is correct for the last 19 years. Take home lesson: The Month of May has become much drier in the last 20 years.
Depending on where you were, May brought both below- and above-average rainfall. Official Athens rainfall was 3.58 inches, compared to a normal 3.86 inches. Here in Wolfskin we got 2.87 inches, so we were below normal. However, looking at the CoCoRaHS reports shows an average of 4.15 inches for Oglethorpe County (we were at the low end here), with a couple of areas getting more than 5 inches. So rainfall was quite variable across the county.
A word about our annual rainfall to date:
Athens has had 21.5 inches officially since January, and that’s about the same (21.38 inches) as we’ve had in Wolfskin. Normal would be 21.3 inches, so there you have it. We’re officially off the drought list, although reservoirs still haven’t fully recharged.
I’ll continue to link to this neat prognosticator in which you can get variously timed precipitation and temperature outlooks. April’s predictions were not so accurate for us, over the one-month outlook, but they couldn’t take into account the unusual tropical moisture that swept the southeast. The prediction for June has moderated a bit to average rainfall and only slightly above average temperatures. Looks like the next three months will be average in both respects. Of course tropical weather drives things around here in the summer so who knows?
Geekstuff:
NOAA’s weekly ENSO update indicates that we’re out of the La Niña conditions that did not hang around quite long enough to be officially a La Niña. Looks like ENSO neutral conditions as far as the eye can see.
Relive your favorite weather events of the year 2008, courtesy of NOAA. NOAA has a neat State of the Climate product. By clicking on the year, such as 2008, you can get to monthly and even weekly reports and zero in on regional descriptions that are much nicer than my own.
Starting in June, I’ve taken over from the first CoCoRaHS Oglethorpe County coordinator. It’s a fairly simple job that mostly involves keeping an eye on the eighteen Oglethorpe County stations, answering questions, and such. The most work is involved in publishing the weekly rainfall totals for each reporting station in the local weekly, the Oglethorpe Echo. And that’s that. Onward:
It’s The merry Month of May, Number 40 in a series. This was the third month of relatively normal weather. Others had much more interesting things to talk about.
From the National Weather Service Climate Prediction Center, this is a plot of high and low temperature anomalies for the US. That’s the difference in the average temperature for this May above or below the average for May over many years, plotted in colors. The anomalies are in Fahrenheit.
The northern tier of states from the Pacific to the Great Lakes were unusually cool for at least the third month in a row (and I presume these temperature anomalies extend into Canada as well). Looks like Kansas and some of the surrounding states were a bit cooler than usual. The eastern US was just slightly warmer than usual in most places.
The most remarkable anomalies occurred in the southwest where parts of California, Nevada, Utah, Colorado, Arizona, and New Mexico experienced temperatures 6-8 degF warmer than usual.
The National Weather Service Climate Prediction Center is hiding these precipitation plots here, and that’s where we’ll find the plot of mean precipitation anomalies for the US over the month of May:
Parts of the southwest got a little relief in the form of rain, but much continued to be dry, as has been generally true since November. Pacific states, except for southern California, got a little extra rain. Conditions were somewhat dry throughout the central states. But the real story for the southeast was rain.
After the sixth month of unusually dry conditions Florida got rain with a vengeance, and much of that spread into south Georgia. A few days ago I posted on the odd nature of the couple of weeks of continuously cloudy or wet weather so I won’t go into that so much here. But I also noted that locally we were about an inch below normal - if you look closely at that map you’ll see that there are tiny patches of neutral white amidst all that green. If you look closely enough you might just see a patch of brown hanging over our house!
For Athens:
It only seemed cooler here than it should be - it really wasn’t, so memory doesn’t always serve.
Here is my plot of high temperatures for the month of May in Athens. (It seemed appropriate to present high temperatures this time.) As usual, the black dots are for the 18 years 1990-2007 (black dots), 2009 (green line), and 2008 (red line).
We almost broke a low on a couple of nights around May 20, and never approached record highs. Nonetheless our average temperature in May was 70.5 degF, compared to 70.0 over many years.
We had NO days that were more than one standard deviation above the mean high daily temperatures, and only two nights more than one standard deviation below the average. That’s so average it’s almost painful.
For rainfall, the figure below shows the Athens data which are official for our area. As usual the green line shows our actual rainfall, the red shows the average accumulation expected. The black dots are rainfall over the last 19 years, the vast river of peach shows the standard deviation. We were above average for most of the month, and then officially ended right at about the average. That figure doesn’t quite display it properly, mainly because the red line average isn’t where it should be, at 3.86 inches. That average is over many years whereas my day to day average is only since 1990. The average rainfall of 3.0 inches you see there is correct for the last 19 years. Take home lesson: The Month of May has become much drier in the last 20 years.
Depending on where you were, May brought both below- and above-average rainfall. Official Athens rainfall was 3.58 inches, compared to a normal 3.86 inches. Here in Wolfskin we got 2.87 inches, so we were below normal. However, looking at the CoCoRaHS reports shows an average of 4.15 inches for Oglethorpe County (we were at the low end here), with a couple of areas getting more than 5 inches. So rainfall was quite variable across the county.
A word about our annual rainfall to date:
Athens has had 21.5 inches officially since January, and that’s about the same (21.38 inches) as we’ve had in Wolfskin. Normal would be 21.3 inches, so there you have it. We’re officially off the drought list, although reservoirs still haven’t fully recharged.
I’ll continue to link to this neat prognosticator in which you can get variously timed precipitation and temperature outlooks. April’s predictions were not so accurate for us, over the one-month outlook, but they couldn’t take into account the unusual tropical moisture that swept the southeast. The prediction for June has moderated a bit to average rainfall and only slightly above average temperatures. Looks like the next three months will be average in both respects. Of course tropical weather drives things around here in the summer so who knows?
Geekstuff:
NOAA’s weekly ENSO update indicates that we’re out of the La Niña conditions that did not hang around quite long enough to be officially a La Niña. Looks like ENSO neutral conditions as far as the eye can see.
Relive your favorite weather events of the year 2008, courtesy of NOAA. NOAA has a neat State of the Climate product. By clicking on the year, such as 2008, you can get to monthly and even weekly reports and zero in on regional descriptions that are much nicer than my own.
