Page 7

Monsoon Season at Ft. Davis

Article and Photos by Ginger Wentrcek

The Ft. Davis area and the McDonald Observatory complex are two of my favorite places to visit. The observatories, scenery, weather, and opportunities for dramatic night sky viewing are in a league of their own, and I always leave there in anticipation of the next visit. The distance from Bryan-College Station to Ft. Davis, 531 miles and an approximately 8.5 hour drive, make the trip extra special when plans come to fruition, but careful planning is essential.

Regardless what you have read about dry weather and clear skies at Ft. Davis, the area has what the locals and the Ft. Davis Chamber of Commerce call the monsoon season, arriving in July and continuing until September. With an average annual rainfall of less than 17 inches, we are not talking about a lot of rain, just enough to cause telescope domes during special viewing nights to remain closed and solar viewing programs canceled.

I absolutely, 100%, without any doubt, positively believe that astrology is a bunch a hooey. Having said that, your stars had better be lined up if you are planning to take a trip to the McDonald Observatory area to do ALL of the following in a short trip: attend the special viewing night at the 82" or 107" telescope, attend a solar viewing program at the Visitor's Center, take the daytime tour to the 107" and HET telescopes, attend a star party in Telescope Park, photograph the beautiful Milky Way, stay at the comfortable and historic Indian Lodge in the state park . . . all on nights where there are no clouds or rain (or rain in the area) and have a decent night where the moon does not wash out the sky. Those last two requirements are the kickers for a short trip like this when one lives so far away.

Planning a Trip to McDonald Observatory

Back in April, I planned a July trip to the McDonald Observatory for another couple plus my husband and me. I got 4 of the rare tickets to observe through the 82" on a night when the sky was 8% illuminated, and tickets for everything else mentioned above, including 2 of the last available rooms at Indian Lodge in the historical section. Then, it was just a matter of waiting for our departure day, which was like watching paint dry, and hoping the weather would cooperate.

Watching the Weather Forecast

July finally arrived and we all watched the weather forecast in anticipation of the trip, paying extra attention to the weather the week before we left. Thunderstorms were forecast during the days and nights of our trip, so I called and canceled our rooms - no need to drive 8.5 hours to see a thunderstorm. But, I took another peek at the weather forecast before cancelling all of our other tickets, and, just like that, all of a sudden, the forecast indicated clear skies with just a few clouds for the days and nights we would be there. Good thing I took that peek, and the trip was back on. The last two rooms at Indian Lodge were still available and the lovely young TAMU student who watches Amazing Grace, our dog, could still drive in from Plano to babysit her. Our stars were aligned.

We watched the weather forecast all the way to Ft. Davis, and it kept changing by the hour. Rain . . . no rain . . . 40% scattered showers . . . 10% scattered showers . . . no scattered showers . . . clear at night . . . not clear at night . . . cloudy at night . . . possible thunderstorms at night. Tim Cowden made the perfect statement in his vacation article that described our situation: “Man plans, the weather laughs.”

Dome Closure Rules - One Drop of Rain

Dome closure rules state “All domes must be closed when hail, mist, rain, sleet or snow appear imminent in the immediate area. Local precipitation alarms/indications are available locally in the 107" dome as well as via the Weather program which has a sensor at the 82" weather tower. If the local 107" alarm is flashing/sounding or the Weather program indicates a closing condition, at least one drop of rain has been detected and the domes should not be opened.”

Official Guidelines - Interesting Reading

We are There

After we arrived, the weather did cooperate, to a degree:

There was rain somewhere in the area on the 82-inch special viewing night, so that was canceled. However, McDonald Observatory personnel did provide a detailed tour of the extraordinary telescope that night, moved it around under a closed dome, and refunded the ticket price to those in attendance.
The almost total cloud cover prevented us from seeing the Milky Way on our first night, but I got up around 3 A.M. and the stars and Milky Way were out in all their glory.
There was a total cloud cover for the solar viewing, so that activity was canceled.
The daytime tours of the larger telescopes were still held, but we could see showers closing in fast.
The weather did hold out for the star party at Telescope Park and the skies were clear; in fact, they were perfect. We were able to look through all of the telescopes that were set up for the event.
After the star party, we went back to the car to collect my camera and tripod so I could set it up in Telescope Park and take photos of the Milky Way with the 107" and 82" observatories in the background. Other than a handful of volunteers who were putting the telescopes away from the star party, we were the last people on the grounds, until we overheard one of the volunteers ask another volunteer, “Have you seen the mountain lion that was reported to have walked through here recently?” The last volunteers were leaving, and we left with them.
We were able to participate in other non-astronomy events as planned.

Daytime showers viewed from 107" catwalk

107" telescope

HET dome

HET mirror

82-inch Otto Struve research telescope

Located on summit of Mt. Locke

Construction Time: 1933-1939

Telescope weight: 45 tons; Primary mirror: 4200 lbs

When available, tickets go fast.

It's old, but strikingly beautiful.

Going Back in August

Fast forward two weeks later. A friend of mine wanted to go to McDonald Observatory and attend all of the activities - star party, special viewing night, tours of major telescopes, and solar viewing with Indian Lodge reservations. She had never seen the Milky Way or looked through one of the giant telescopes, and this was going to be a fun “girls' trip.” I was able to obtain tickets for the 107 inch telescope on a night that was 13% illuminated and tickets for all of the activities. Two rooms were still available at Indian Lodge, so I booked them. The trip was on.

The Weather Drama Starts Again

A week before we were to leave, the weather forecast drama started again. We had to cancel our tickets at least 72 hours prior to the special viewing night in order to get a “rain check” for another viewing night and not lose our money. We watched the forecast each day and ended up cancelling our tickets at the last possible minute because thunderstorms were predicted every day/night of our trip. We both promised each other we would not peek at the forecast after we canceled and be content that we made the right decision. No second guessing!

Well, we both peeked within the hour of cancelling all of our tickets. Yes, the forecast changed and isolated thunderstorms were predicted during the day but the nights were supposed to be clear. The forecast went back and forth, thunderstorms at night/no thunderstorms at night. In the end, we made the right decision to cancel. It did rain during the day and nights of the special viewing through the 107 inch and star party. Granted, it was not a lot of rain, but enough that the dome of the 107" would remain closed.

Thunderstorms Continue

Out of curiosity, I checked the weather forecast each week after that, and there were weeks when thunderstorms were predicted every day of every week during the Ft. Davis monsoon season. As mentioned earlier, it is not a lot of rain, but enough to keep the dome closed on special viewing nights. Since we can use our tickets next year, as the old saying goes, We will return.

The image in the banner at the top of the page was taken from a webcam located on the catwalk of the 107" observatory. The image on the webcam was taken August 13 at 6:30 P.M., CDT.

Get the latest forecast here: National Weather Service - Extended Forecast for Ft. Davis