Sunday, April 17, 2022

A Slow Start to the Hail Season

CoCoRaHS' annual Hail Week has come to a close, but this post wraps it up with some additional climatological information on hail. If you have been following this week's Messages of the Day you have seen how to measure hail, report it, and how to make a hail pad. (Mobile app users should select "View message of the day" after submitting you daily observation). Hail is a fascinating phenomena and there is a lot of information available if you want to learn more about it. The CoCoRaHS Hail page  has some information, and you can find a lot more information at Living With Weather- Hail on the Midwestern Regional Climate Center website.

Compared to the past few years this hail season is getting off to a slow start. The total number of March hail reports (155) is the lowest since 2011.

Hail reports for January through April 2015-2022

The peak of the hail season is May, June, and July as can be seen in this chart. Note the downward trend in the number of hail report the past five years.

Total hail reports for each year 2015-2022

Normally probabilities for significant hail very low at the end of February and only begin to ramp up in mid-March to early April. Here are the climatological probabilities for significant hail from the the NOAA Storm Prediction Center for mid-April, late May, and August. The center of the high probabilities moves north through April and May, reaching a peak in late May. By early August probabilities are diminished and continue to diminish into early fall.

So far CoCoRaHS observers have submitted 491 hail reports on 60 days (through 4/12), about the same as last year's 498 reports. This map is a compilation of hail reports for the year through April 12 from the Storm Prediction Center. Note that this map is for reports of hail one inch in diameter or larger.

CoCoRaHS has one of the most comprehensive collections of detailed data on hail. While measuring and reporting hail may seem to be secondary to rain and snow, our hail observations provide valuable information not only to the National Weather Service but to others such as the insurance industry. A 2019 article in the Washington Post noted that Texas has experienced 36 $100 million disasters from severe thunderstorms in the past 25 years. Twenty-nine of these $100 million disasters were from hail!

Measuring hail is a core mission of CoCoRaHS, and the separate hail reports on the CoCoRaHS web site allow you to submit your hail information. There are a few things you need to know before measuring hail, and you can find that information in our "Measuring Hail" training animation. Here is a hail size reference and measuring guide you can download, print, and laminate for use. The rule on the bottom is to scale and fits on a 3x5 card. Make multiple copies and keep one at home, in the car, or at work.

Tuesday, April 5, 2022

Keeping Birds Off of Your Rain Gauge

Spring...when flowers bloom, gardens get planted, and birds sometimes decide to use the 4-inch rain gauge for a perch and/or a porta-potty. Although a properly perched bird or two can be a great photographic opportunity, more often than not they leave a mess. What can you do to discourage our feathered friends from perching on the gauge while at the same time not affecting the catch of the rain gauge?  A few years ago Nolan Doesken, CoCoRaHS founder, put out an appeal for suggestions on how to deal with this problem. He received quite a range of ideas. Here are a few of them.

  • Use tape to attach tooth picks or thin, rigid wires to the rim of the gauge about every1 ½ to 2 inches and sticking up about 2" above the rim.
  • Mount a ring of stakes with flags or streamers or shiny stuff around your gauge making sure they stick up a bit higher than the gauge. You can now even purchase holographic ribbon tape that is claimed to scare away birds.
  • Real cats
  • Stuffed cats
  • Rubber snakes
  • Real snakes
  • Plastic owls
  • Electronic owls
  • WD-40 or similar smelly solvent/lubricant applied to the outside of the funnel. A problem with this is that it will likely have to reapplied often, and it could be messy.

I tried one trick suggested by an observer in our CoCoRaHS Facebook group last year. They suggested putting something in the vicinity of the gauge higher than the top of the funnel. Birds often perch on the funnel because it's the highest vantage point in the area. If you give them something that is higher than the gauge, they will tend to use that instead. This could be a shepherd's hook plant hanger or something similar. I attached pieces of scrap wood to my post in an "L" configuration. This seemed to work well as I only had one to two instances of "improper use of the funnel". 


If you search "birds" in our Facebook group you will find photos of some rather ingenious wire configurations to deter birds. Here is one of my favorites (which no doubt took a lot of work) by Richard Martin. If I were a bird I'd think twice about getting close to this one!

 No photo description available.

Two things to keep in mind if you are creating your own deterrent. Nothing should be in the funnel, and any wires, etc. should be bent slightly away from the funnel so that water doesn't collect on them and drip into the gauge.

The toothpick/wire idea is probably the easiest. Here are some instructions on making the toothpick deterrent.

  1. Cut about a 14 inch long piece of ¾ duct tape. Lay it adhesive side up on a flat surface, and fasten down each end with a small piece of tape.
  2. Arrange toothpick on the tape about one to one and a half inches apart. Round toothpicks are best – the have a little more heft to them. Press the toothpicks on to the tape so they adhere.
  3. When you have arranged all the toothpicks, cut the strip free on both ends, inside of where you taped it down.
  4. Wrap the tape with the toothpicks around the edge of the funnel, keeping the top edge of the tape at or just below the edge of the funnel. Overlap the ends, and then press firmly all around the funnel.

For the photos below I used masking tape, but that will not hold up very long in wet weather. Duct tape or some other moisture resistant tape is best. Since you won’t find duct tape in a ¾” width, you will need to rip a strip approximately that wide from a wider strip. This is easy to do – first snip the end of the wide piece of tape with a scissors, and then rip the narrower piece off.

Good luck with the birds this season.