They are latin abbreviations, ante meridiem (before midday) for a.m and post meridiem (after midday) for p.m.
antemeridian is AM; postmeridian is PM.
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The acronym PM can mean post meridian, which is the time from noon until midnight, or it can mean prime minister.
AM: Ante Meridiem; PM: Post Meridiem
post meridem
Am = Ante meridian and Pm = post meridian
Tornadoes can form at any time of day or night. The time from 3 PM to 9 PM is the most common time for tornadoes to form.
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It is necessary to specify the hour when giving the time in that form.
8:22 pm
Yes. This is the time when they are most likely to occur. However, tornadoes can form at any time of day or night.
AM is ante meridian - After 12Midnight and before 12 Noon. PM is post meridian - After 12 Noon and Before 12 Midnight.