This report describes the historical weather record at the Baltimore-Washington Thurgood Marshall International Airport (Baltimore, Maryland, United States) during 1959. This station has records back to December 1947.
Baltimore, Maryland has a warm humid temperate climate with hot summers and no dry season. The area within 25 mi of this station is covered by forests (48%), built-up areas (23%), oceans and seas (18%), and croplands (9%)
Daylight saving time (DST) was observed at Baltimore, Maryland during 1959. There were two time changes during 1959:
1959 was not a leap year, so it has 365 days and no February 29th. The first leap year before 1959 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 1959 they occurred on:
|Spring Equinox||Saturday, 21 March 1959.|
|Summer Solstice||Monday, 22 June 1959.|
|Fall Equinox||Wednesday, 23 September 1959.|
|Winter Solstice||Tuesday, 22 December 1959.|
The hottest day of 1959 was June 30, with a high temperature of 100°F. For reference, on that day the average high temperature is 86°F and the high temperature exceeds 94°F only one day in ten. The hottest month of 1959 was August with an average daily high temperature of 86°F.
Relative to the average, the hottest day was April 9. The high temperature that day was 89°F, compared to the average of 62°F, a difference of 27°F. In relative terms the warmest month was May, with an average high temperature of 78°F, compared to an typical value of 74°F.
The longest warm spell was from September 21 to October 12, constituting 22 consecutive days with warmer than average high temperatures. The month of September had the largest fraction of warmer than average days with 70% days with higher than average high temperatures.
The coldest day of 1959 was January 18, with a low temperature of 6°F. For reference, on that day the average low temperature is 25°F and the low temperature drops below 13°F only one day in ten. The coldest month of 1959 was January with an average daily low temperature of 22°F.
Relative to the average, the coldest day was January 18. The low temperature that day was 6°F, compared to the average of 25°F, a difference of 19°F. In relative terms the coldest month was January, with an average low temperature of 22°F, compared to an typical value of 26°F.
The longest cold spell was from September 12 to September 23, constituting 12 consecutive days with cooler than average low temperatures. The month of March had the largest fraction of cooler than average days with 71% days with lower than average low temperatures.
The clearest month of 1959 was September, with 63% of days being more clear than cloudy. The longest spell of clear weather was from June 4 to June 12, constituting 9 consecutive days that were clearer than they were cloudy.
The cloudiest month of 1959 was January, with 23% of days being more cloudy than clear.
This station reports both the quantity of liquid precipitation and categorical observations of precipitation (e.g., moderate rain, or heavy snow). Both are subject to erroneous reports, but the former is particularly prone to false reports, especially ones indicating an excessive quantity of precipitation. Please bear this in mind when reading the extrema reported in this section.
The day with the largest quantity of precipitation was June 2. That day saw 2.370" of liquid (or liquid equivalent) precipitation, compared to a median value of 0.157". The month with the most precipitation was July, with 6.016", compared to a median value of 3.756".
As determined by quantitative measurements, the longest dry spell was from September 3 to September 17, constituting 15 consecutive days with no measured precipitation. The month with the largest fraction of dry days was September, with 87% of days reporting no measured precipitation at all.
The month with the largest fraction of days with at least some measured precipitation was October, with 39% of days reporting some measured precipitation.
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 1959 with the most precipitation observations was February 14. There were 24 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 December, with 121 hourly present weather reports involving some form of precipitation.
As determined by the present weather reports, the longest dry spell was from September 4 to September 17, constituting 14 consecutive days with no observed precipitation. The month with the largest fraction of days without observed precipitation was September, with 73% of days reporting no observed precipitation at all.
The month with the largest fraction of days with at least some observed precipitation was February, with 46% of days reporting some observed precipitation.
In this section we consider only those weather reports that indicate liquid precipitation. For the purposes of this analysis, we include thunderstorms even though some thunderstorms are not accompanied by liquid precipitation.
The month of 1959 with the largest number of those reports was December, with a total of 101 reports. The day with the largest number of those reports was February 14, with a total of 24 reports.
This station reports when snow is observed falling but does not report the quantity of snow that has fallen or the depth of snow on the ground.
In this section we consider hourly weather reports that contain an observation of falling snow. These reports do not necessarily correspond to accumulation.
The first reported snow fall in 1959 was on December 1; the last was on April 12. The month of 1959 with the largest number of those reports was January, with a total of 37 reports. The day with the largest number of those reports was January 26, with a total of 17 reports.
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 1959 was March with an average daily low humidity of 36%, and the most humid month was July with an average daily low humidity of 54%.
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 1959, January had 27 dry days, 4 comfortable days, and no humid days; April had 16 dry days, 14 comfortable days, and no humid days; July had no dry days, 5 comfortable days, and 26 humid days; and October had 12 dry days, 10 comfortable days, and 9 humid days.
The highest sustained wind speed was 38 mph, occurring on December 7; the highest daily mean wind speed was 26 mph (December 7);
The windiest month was March, with an average wind speed of 13 mph. The least windy month was December, with an average wind speed of 9 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 1959 with the lowest average visibility was February 14, with an average visibility of 1.1 mi. The month with the lowest average visibility was August, with an average visibility of 7.7 mi. With an average visibility of 12.7 mi, the month of January had the highest average visibility.
The cloud ceiling is the altitude of the lowest layer of clouds that are at categorized as broken (mostly cloudy) or overcast (cloudy). If no such cloud layer exists then the ceiling is unlimited and no value is reported.
The day of 1959 with the lowest average cloud ceiling was November 22, with an average cloud ceiling of 20'. The month with the lowest average cloud ceiling was October, with an average cloud ceiling of 6381'. The month of May has the highest average cloud ceiling, with an average cloud ceiling of 25871'.