Gravity is a force that most of us don’t think about. That is, until you try to launch several tons of satellite into orbit.
On Jan. 20, the Delta IV Heavy, the largest rocket to ever be launched from the West Coast, successfully blasted off into space from Vandenberg Air Force Base in northern Santa Barbara County.
The Delta IV Heavy rocket can place a payload of 13,800 pounds in geosynchronous orbit, 22,000 miles above sea level.
The sound of this massive rocket could be heard as far north as Shell Beach.
Carol Schmidt, who has lived in Shell Beach for more than 30 years, said, “It was the fattest contrail I had ever seen! I could actually see the flame. Suddenly, I noticed the noise. I could actually hear the faint roar — that was also a first. I turned to look at the clock — it had taken about five minutes for the sound to get to me.”
To successfully launch a rocket that is as tall as a 23-story building takes good weather.
Clouds, precipitation, winds, turbulence and especially lightning can delay a rocket launch. Vandenberg is uniquely equipped with more than 270 specialized weather sensors that monitor all aspects of the weather. One way to check the weather is by launching a weather balloon.
Every day around 4 a.m., the 30th Weather Squadron from Vandenberg launches a weather balloon with a tiny transmitter called a radiosonde attached.
As the weather balloon rises through the atmosphere, this transmitter broadcasts back to the receiving station readings on temperature, pressure and humidity levels, as well as Global Positioning System coordinates for the winds.
The data from these balloons can determine the stability of the atmosphere and any wind shear that may be present.
Wind shear is a difference in wind speed and direction over a relatively short distance in the air column.
Wind shear can produce severe turbulence as the rocket ascends through the atmosphere, damaging vital components.
Before the Delta IV launch, the 30th Weather Squadron released 12 balloons to support the launch, about one every 30 minutes.
The balloons are made out of latex rubber and filled with helium. At sea level, before they are launched, they are about 4 feet in diameter.
When they reach 100,000 feet, they expand to more than 40 feet in diameter, and by 110,000 feet they usually rupture.
When they pop, the radiosonde — about the size of a milk carton — comes floating back to earth on a small parachute.
This week’s forecast
Gentle to moderate (8- to 18-mph) northwesterly (onshore) winds will allow the marine layer to redevelop along the coastline and into a few of the coastal valleys this morning and tonight.
The cool marine air coming off the Pacific Ocean will get cooler throughout San Luis Obispo County with most locations reaching the mid- to high 60s.
The Eastern Pacific high will slide southward toward the Baja Peninsula. At the same, the strong high pressure ridge responsible for the dry weather during the first part of February will gradually weaken and migrate westward.
This condition will produce a major change in the weather pattern.
A 990-millibar low pressure system will develop off the Oregon coastline.
The associated cold front will stall about 100 miles north of San Luis Obispo but will still produce increasing southerly winds, cooler temperatures and extensive clouds and scattered rain showers Monday and Tuesday.
Most of the rain will remain north of Monterey Bay during this period.
A 1,001-milibar low will drop out of the Gulf of Alaska later Tuesday, and the aforementioned cold front will finally move over the Central Coast from north to south Wednesday with increasing southerly winds and rain.
At this time, rainfall totals should range between 0.75 and 1.25 inches by Wednesday night.
Snow is expected across the Sierra, with snow levels initially at 6,500 feet, then dropping to 3,000 feet or possibly lower by Wednesday.
Maximum temperatures late next week will only range from the low to mid-50s, with minimums in the 30s to low 40s.
A break in the wet weather should develop Thursday. However, another stronger storm system is forecast to reach the Central Coast on Friday with gale force southerly winds and periods of heavy rain.
Surf and sea report
Today’s 3- to 5-foot west-northwesterly (285-degree deep-water) swell (with a 14- to 16-second period) will continue at this height but with shorter periods through Monday.
Combined with this west-northwesterly swell will be 2- to 4-foot southerly (180-degree shallow-water) seas Monday.
A 7- to 9-foot westerly (265-degree deep-water) sea and swell (with a 6- to 12-second period) will develop along our coastline Tuesday.
A series of storms in the Gulf of Alaska will produce an 11- to 13-foot northwesterly (320-degree deep-water) swell (with a 13- to 16-second period) along our coastline Wednesday and will remain at this height and period through Thursday.
Increasing southerly seas are forecast Friday.
Seawater temperatures will range between 53 and 55 degrees through today, increasing to 54 and 56 degrees Monday and will remain at this level through Friday.
To learn more about energy sources that are free of fossil fuels, log on to the Next100.com website.
It’s supported by PG&E and provides an in-depth look at the intersection of clean energy and the environment.
John Lindsey is a media relations representative for PG&E. He is also a local weather expert and has lived along the Central Coast for more than 24 years. To subscribe to his daily weather forecast or ask him a question, e-mail firstname.lastname@example.org.