Historical Weather For 1958 in San Diego, California, USA

Location

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%)

Calendar

Daylight saving time (DST) was observed at San Diego, California during 1958. There were two time changes during 1958:

  • DST started on Sunday April 27, 1958 at 3:00 am, from PST (GMT-8) to PDT (GMT-7).
  • DST ended on Sunday September 28, 1958 at 1:00 am, from PDT (GMT-7) to PST (GMT-8).

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.

Temperature

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.

Temperature

The daily low (blue) and high (red) temperature during 1958 with the area between them shaded gray and superimposed over the corresponding averages (thick lines), and with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile). The bar at the top of the graph is red where both the daily high and low are above average, blue where they are both below average, and white otherwise.

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.

Hourly Temperature Bands

The full year of hourly temperature reports with the days of the year on the horizontal and the hours of the day on the vertical. The hourly temperature measurement is color coded into meaningful temperature bands: frigid is purple (below 15°F), freezing is blue (15°F to 32°F), cold is dark green (32°F to 50°F), cool is light green (50°F to 65°F), comfortable is yellow (65°F to 75°F), warm is light red (75°F to 85°F), hot is medium red (85°F to 100°F), sweltering is dark red (above 100°F), and missing data is pink.

Clouds

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.

Cloud Coverage

The fraction of time spent in each of the five sky cover categories over the course of 1958 on a daily basis. From top (most blue) to bottom (most gray), the categories are clear, mostly clear, partly cloudy, mostly cloudy, and overcast. Pink indicates missing data. Outside of the United States clear skies are often reported ambiguously, leading them to be lumped in with the missing data. The bar at the top of the graph is gray if the sky was cloudy or mostly cloudy for more than half the day, blue if it is clear or mostly clear for more than half the day, and blue-gray otherwise.

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.

Hourly Cloud Coverage

The full year of hourly cloud coverage reports with the days of the year on the horizontal and the hours of the day on the vertical. The sky cover is color coded: from most blue to most gray, the categories are clear, mostly clear, partly cloudy, mostly cloudy, and overcast. Pink indicates missing data. Outside of the United States clear skies are often reported ambiguously, leading them to be lumped in with the missing data.

Precipitation

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.

Present Weather Reports

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.

Precipitation Reports

The daily number of hourly observed precipitation reports during 1958, color coded according to precipitation type, and stacked in order of severity. From the bottom up, the categories are thunderstorms (orange); heavy, moderate, and light snow (dark to light blue); heavy, moderate, and light rain (dark to light green); and drizzle (lightest green). Not all categories are necessarily present in this particular graph. The faint shaded areas indicate climate normals. The bar at the top of the graph is green if any precipitation was observed that day and white otherwise.

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.

Hourly Weather Reports

The full year of hourly present weather reports with the days of the year on the horizontal and the hours of the day on the vertical. The color-coded categories are thunderstorms (orange); heavy, moderate, and light snow (dark to light blue); heavy, moderate, and light rain (dark to light green); drizzle (lightest green); freezing rain and sleet (light and dark cyan); snow grains (lightest blue); hail (red); fog (gray); and haze (brownish gray).

Snow

Either snow is exceptionally rare at this location or this station did not reliably report it during 1958.

Humidity

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.

Humidity

The daily low (brown) and high (blue) relative humidity during 1958 with the area between them shaded gray and superimposed over the corresponding averages (thick lines), and with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).

Dew 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.

Dew Point

The daily low (blue) and high (red) dew point during 1958 with the area between them shaded gray and superimposed over the corresponding averages (thick lines), and with percentile bands (inner band from 25th to 75th percentile, outer band from 10th to 90th percentile).

Wind

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.

Wind Speed

The daily low and high wind speed (light gray area) and the maximum daily wind gust speed (tiny blue dashes).

Visibility

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.

Visibility

The daily average visibility, depicted as gray bars encroaching down from the top of the graph.

Cloud Ceiling

This station did not reliably report the cloud ceiling during 1958.