To maximize fuel efficiency on a roadway trip, keeping your tires properly inflated is paramount. Something comparable can be said around providing specific weather forecast. Simply put, air pressure is key.

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The solid invisible pressure of gravity accelerates trillions of wait molecules toward the earth’s surface and also produces weight. The weight of the wait is what we feel as pressure. Imagine a 1-square-inch pillar of waiting measured from the top of the setting down come sea level — it would weigh about 14.7 pounds. Every the air surrounding the planet would weigh about 5,600 trillion tons.

Normally us don’t notification it since our bodies maintain an inner pressure the balances the external pressure. But swift changes in elevation can cause us come detect atmospheric pressure changes.

One local instance can be found driving come Sequoia National woodland in the Sierra Nevada. Maybe you have actually felt your ears “pop.” as you travel greater and greater in the mountains. That is resulted in by her inner ear trying come equalize the press with the of the external air.

Meteorologists regularly express air pressure in units referred to as “millibars.” The typical atmospheric press is identified as being same to 1,013.25 millibars in ~ sea level. Relying on the neighboring atmospheric conditions, levels over this value might be considered areas of high pressure. In the main Valley, 1,030 millibars and above is considered solid high pressure. Frequently in the central Valley, solid high pressure produces clear and dry weather.

In the unified States, barometric pressure for aviation is measured in customs of mercury, or “inHg”. One inHg is the push exerted by a shaft of mercury 1 customs high in ~ the traditional acceleration the gravity. For this reason that traditional 1,013.25 millibars in ~ sea level is the tantamount of 29.92 inHg.

The highest pressure reading in the unified States emerged Jan. 31, 1989, at Northway, Alaska, a town with a population of 71 souls. On the day, wait temperature dropped to 62 degrees below zero, and also the push reached 1,078.6 mb, or 31.58 inHg. That reading is literally turn off the scale for many analog barometers.

If famed writer Jack London to be alive, the would probably write a story around the ground connection of bush aircraft that carry mail and also supplies because their altimeters might not be calibrated because of such pressure readings. Friend see, precise altimeter analysis is vital for plane to stop mountains. The highest possible pressure ever before recorded in the reduced 48 states occurred in December 1983 in miles City, Montana, wherein it got to 1,064 mb, or 31.42 inHg, during a significant cold wave.

The embraced figure for the world’s greatest recorded sea-level push in the world developed in Agata, Siberia, which got to 1,084 mb, or 32.01 inHg, in December 1968. At the time of that reading, it was about 50 degrees below zero. ~ above the flip side, and also once again depending upon the surrounding atmospheric conditions, levels below standard atmosphere may be considered locations of low pressure.

Generally speaking, the reduced the pressure, the much more unsettled the weather will become. In respectable 2005, Hurricane Katrina got to 920 millibars. In October 2005, Hurricane Wilma reached 882 millibars over the open waters the the Caribbean. The lowest sea-level pressure ever before recorded an international was 870 millibars once Typhoon tip passed Guam and rapidly intensified together it relocated toward Japan throughout October 1979. The i of tip through the region resulted in eight ships being grounded or sunk. A Chinese freighter broke in half as a an outcome of the typhoon, but its crew of 46 was rescued. Tragically, 13 U.S. Marines lost their stays at Camo Fuji in Japan because of that storm.

John lindsey is Pacific Gas and also Electric Co.’s Diablo Canyon power Plant marine meteorologist and a media relationships representative.



John Lindsey

Hanford"s five day forecast

Friday marked the beginning of a far-reaching heat event throughout the central Valley that will last through many of following week together high push over the Southwestern United states strengthens and also expands.

High temperatures in Hanford will reach 106 degrees on Sunday, further warming come 110 levels by Tuesday. If this temperature forecast verifies, record-breaking day-to-day Hanford high temperatures records are likely to be damaged on Monday, Tuesday and Wednesday.

Further south, Bakersfield is forecast to hit 113 ~ above Tuesday, which would break the previous document of 107 degrees set-back in 1947.

Current longer-range models ultimately indicate a cooling tendency will begin near the coast next weekend, although temperatures will most likely remain well over seasonable.

Temperatures because that HanfordSaturday - 73/101 - record temp 110 in 1961Sunday - 75/105 - record temp 108 in 1917Monday - 76/108 - record temp 110 in 1920Tuesday - 78/109 - document temp 109 in 1961Wednesday - 78/107 - document temp 108 in 1961Thursday - 74/105

If you heading come the main California coastline:

Atmospheric condition

Along the beaches, the northwesterly winds will certainly decrease and enable the return that the maritime layer on Sunday right into Monday. Naval low clouds, fog and also mist will certainly spread into the seaside valleys during the overnight hours, resulting in cool temperatures.


Saturday"s 6- to 8-foot northwesterly (310-degree, deep-water) sea and swell (with a 5- come 11-second period) will come to be a 4- come 6-foot northwesterly (300-degree, deep-water) puffy (with an 8- to 11-second period) follow me the coastline on Sunday right into Thursday.

Along the beaches, the northwesterly winds will certainly decrease and enable the return that the naval layer on Sunday into Monday. Naval low clouds and also fog will spread into the seaside valleys during the overnight hours, leading to cool temperatures.

Seawater temperature will range between 51 and also 53 levels through Thursday.

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At PG&E, the security of our customers and employees is our optimal priority. This week’s hot and also dry weather can develop hazardous health conditions. Walk to a cool place: consider going come an air-conditioned mall, library or other public ar that will be cool. Walk to a neighbor, friend or residence that has air conditioning. Contact 1-877-474-3266 for an ext information.