This report describes the historical weather record at the Brown Municipal Airport (San Diego, California, United States) during 1958. This station has records back to July 1954.
San Diego, California has a cold semi-arid steppe climate. The area within 25 mi of this station is covered by shrublands (60%), oceans and seas (27%), and built-up areas (11%)
Daylight saving time (DST) was observed at San Diego, California during 1958. There were two time changes during 1958:
1958 was not a leap year, so it has 365 days and no February 29th. The first leap year before 1958 was 1956 and the first after was 1960.
The summer and winter solstices and the spring and fall equinoxes mark the passing of the seasons. They fall on nearly the same day each year, with differences of a day or two depending on the year. In 1958 they occurred on:
|Spring Equinox||Friday, 21 March 1958.|
|Summer Solstice||Saturday, 21 June 1958.|
|Fall Equinox||Tuesday, 23 September 1958.|
|Winter Solstice||Monday, 22 December 1958.|
The hottest day of 1958 was October 16, with a high temperature of 102°F. For reference, on that day the average high temperature is 75°F and the high temperature exceeds 84°F only one day in ten. The hottest month of 1958 was September with an average daily high temperature of 80°F.
Relative to the average, the hottest day was October 16. The high temperature that day was 102°F, compared to the average of 75°F, a difference of 27°F. In relative terms the warmest month was December, with an average high temperature of 71°F, compared to an typical value of 66°F.
The longest warm spell was from May 14 to May 30, constituting 17 consecutive days with warmer than average high temperatures. The month of December had the largest fraction of warmer than average days with 68% days with higher than average high temperatures.
The coldest day of 1958 was January 21, with a low temperature of 35°F. For reference, on that day the average low temperature is 47°F and the low temperature drops below 40°F only one day in ten. The coldest month of 1958 was January with an average daily low temperature of 45°F.
Relative to the average, the coldest day was November 17. The low temperature that day was 36°F, compared to the average of 51°F, a difference of 15°F. In relative terms the coldest month was March, with an average low temperature of 47°F, compared to an typical value of 50°F.
The longest cold spell was from July 6 to July 30, constituting 25 consecutive days with cooler than average low temperatures. The month of July had the largest fraction of cooler than average days with 90% days with lower than average low temperatures.
The clearest month of 1958 was September, with 87% of days being more clear than cloudy. The longest spell of clear weather was from July 7 to July 21, constituting 15 consecutive days that were clearer than they were cloudy.
The cloudiest month of 1958 was February, with 32% of days being more cloudy than clear. The longest spell of cloudy weather was from January 28 to February 2, constituting 6 consecutive days that were cloudier than they were clear.
This station provides hourly reports of significant weather events at and around the station, but does not report the quantity of precipitation at the station itself. This is common for weather stations located outside of the United States, and for a small subset of stations in the United States that are located at lesser used and smaller airports.
This station reports when significant weather events (including precipitation) are visually observed at or near the station. Such events do not always correspond to measured quantities of liquid equivalent precipitation, such as when the event is near by not at the station, or in the case of solid precipitation that does not melt in the collection basin.
The day in 1958 with the most precipitation observations was February 3. There were 13 hourly weather reports that day (out of a maximum of 24) in which some form of precipitation was observated at or near the station. The month with the most precipitation observations was March, with 60 hourly present weather reports involving some form of precipitation.
As determined by the present weather reports, the longest dry spell was from May 12 to August 6, constituting 87 consecutive days with no observed precipitation. The months June and July were completely without observed precipitation.
The month with the largest fraction of days with at least some observed precipitation was March, with 58% of days reporting some observed precipitation.
Either snow is exceptionally rare at this location or this station did not reliably report it during 1958.
Humidity is an important factor in determining how weather conditions feel to a person experiencing them. Hot and humid days feel even hotter than hot and dry days because the high level of water content in humid air discourages the evaporation of sweat from a person's skin.
When reading the graph below, keep in mind that the hottest part of the day tends to be the least humid, so the daily low (brown) traces are more relevant for understanding daytime comfort than the daily high (blue) traces, which typically occur during the night. Applying that observation, the least humid month of 1958 was December with an average daily low humidity of 36%, and the most humid month was August with an average daily low humidity of 63%.
But it is important to keep in mind that humidity does not tell the whole picture and the dew point is often a better measure of how comfortable a person will find a given set of weather conditions. Please see the next section for continued discussion of this point.
Dew point is the temperature below which water vapor will condense into liquid water. It is therefore also related to the rate of evaporation of liquid water. Since the evaporation of sweat is an important cooling mechanism for the human body, the dew point is an important measurement for understanding how dry, comfortable, or humid a given set of weather conditions will feel.
Generally speaking, dew points below 50°F will feel a bit dry to some people, but comfortable to people accustomed to dry conditions; dew points from 50°F to 68°F are fairly comfortable to most people, and dew points above 68°F are increasingly uncomfortable, becoming oppressive around 77°F.
To take some examples, and basing our categorization on the daily high dew point in 1958, January had 10 dry days, 21 comfortable days, and no humid days; April had no dry days, 29 comfortable days, and 1 humid day; July had no dry days, 31 comfortable days, and no humid days; and October had 1 dry day, 28 comfortable days, and 2 humid days.
The highest sustained wind speed was 32 mph, occurring on November 15; the highest daily mean wind speed was 18 mph (November 15);
The windiest month was March, with an average wind speed of 7 mph. The least windy month was July, with an average wind speed of 6 mph.
Visibility is the maximum distance at which a given reference object or light can be clearly discerned. In the United States, visibilities that are greater than or equal to 10 miles are typically reported as 10 miles.
The day of 1958 with the lowest average visibility was October 12, with an average visibility of 0.6 mi. The month with the lowest average visibility was July, with an average visibility of 7.0 mi. With an average visibility of 15.7 mi, the month of March had the highest average visibility.
This station did not reliably report the cloud ceiling during 1958.