Hand Analysis

This is how I have learned to analyze surface and upper air maps through my education and by working at several different places as a professional meteorologist. If you recognize certain techniques then you have probably worked at some of my prior employers. Keep in mind that these "rules" are not the be all end all for Hand Analysis...they are just techniques I happen to use.

The following are Rules for Surface and Upper Air Analysis

Surface Analysis:
     Mean Sea Level Pressure Contours: At 2mb intervals using 1000mb as the baseline.
     Pressure centers and central values: High - blue H / Low - red L
     Isotherms: Every 2 degrees Fahrenheit, using fine solid red lines.
     Isodrosotherms: Every 5 degrees Fahrenheit for values greater than 60 F, using fine solid green lines.
     Frontal boundaries:
          Warm Front (RED line of semi-circles pointing in the direction of travel),
          Cold Front (BLUE line of triangle-shaped pips pointing in the direction of travel),
          Occluded Front (PURPLE line with alternating half-circles and triangles pointing in direction of travel),
          Stationary Front (alternating RED half-circles and BLUE spikes pointing in opposite directions),
          Dry Line (ORANGE line with scallops facing into the moist sector) and
          Surface Trough (BLACK dashed line indicating the wind shift).
   Example of a Surface Analysis.

925mb Analysis: Key parameters are analyzed in BLACK unless noted otherwise below.
     Streamline in pencil. Depict axes of confluent winds using black (-XX-) lines.
     Axes of maximum wind flow: 25 kts, using broad solid black arrows with all speed maxima labeled.
     Isotherms: Every 2 Celsius degrees, using fine solid red lines with the 0C isotherm in blue.
     Thermal ridges: Red dots (^{. . . . .}).
     Warm and cold pockets: Warm - red W/ Cold - Blue K
     Isodrosotherms: Every 2 Celsius degrees for values of 10C, using fine solid green lines.
     Axes of maximum dew points: Broad solid green wavy lines for moisture advection, and broad dashed green wavy line against the flow.
     Moisture areas (outside of 6C isodrotherm): For areas of T-Td of 6C, enclose in a fine green scalloped lines.
     Circulation centers: Cyclones - black C/ Anticyclones black A
     Dry Air Intrusion: Dry air (10C degrees drier) intruding into a significant moisture field (dewpoint depressions < 6C), using fine black (- - -) lines. Do not depict this immediately upwind of a moisture axis.
     Example of a 925mb Analysis.

850mb Analysis: Key parameters are analyzed in RED unless noted otherwise below.
     Streamline in pencil. Depict axes of confluent winds using red (-XX-) lines.
     Axes of maximum wind flow: 25 kts, using broad solid red arrows with all speed maxima labeled.
     Isotherms: Every 2 Celsius degrees, using fine solid red lines with the 0C isotherm in blue.
     Thermal ridges: Red dots (^{. . . . .}).
     Warm and cold pockets: Warm - red W/ Cold - Blue K
     Isodrosotherms: Every 2 Celsius degrees for values of 6C, using fine solid green lines.
     Axes of maximum dew points: Broad solid green wavy lines for moisture advection, and broad dashed green wavy line against the flow.
     Moisture areas (outside of 6C isodrotherm): For areas of T-Td of 6C, enclose in a fine green scalloped lines.
     Circulation centers: Cyclones - red C/ Anticyclones red A
     Dry Air Intrusion: Dry air (10C degrees drier) intruding into a significant moisture field (dewpoint depressions < 6C), using fine red (- - -) lines. Do not depict this immediately upwind of a moisture axis.
     Example of an 850mb Analysis.

700mb Analysis: Key parameters in BROWN.
     Streamlines in pencil.
     Axes of maximum wind flow: 30 kts, using broad solid brown arrows with all speed maxima labeled.
     Isotherms: Every 2 Celsius degrees, 6C, using fine solid red lines with the 0C isotherm in blue.
     Moisture areas: For areas with a T-Td of 6C, enclose in a fine green scalloped lines.
     Circulation centers: Cyclones - brown C/ Anticyclones - brown A
     Dry Air Intrusion: Drawn using broad brown dashed (- - - - -) line.
     Example of a 700mb Analysis.

500mb Analysis: Key parameters are outlined in BLUE.
     Contour Analysis: At 60m intervals, using 5400m (540dam) as the baseline, in fine solid black lines.
     Axes of maximum wind flow: 30 kts ( 40 kts in winter), using broad solid blue arrows with all speed maxima labeled.
     Isotherms: Every 2 Celsius degrees, using fine solid red lines.
     Moisture areas: For areas with a T-Td of 6C, enclose in a fine green scalloped lines.
     Thermal (cold) troughs: Depicted as a broken blue cold front ( ).
     Warm and cold pockets: Warm - blue W/ Cold - Blue K
     Height centers and central values: High - blue H / Low - blue L
     12 hours height falls: Every 30m (3dam), using fine blue lines with rectangular barbs pointing toward the height fall center. If the center exceeds 180m (18dam), draw height falls isopleths every 60m (6dam). Label the center with an X and the maximum value.
     Difluent regions or speed divergence: Broad blue zigzag (WWWWW) lines.
     Areas of speed divergence: Broad blue wavy lines (speed divergence 30 kts/90NM)
     Example of a 500mb Analysis.

300mb and 200mb Analysis: Key parameters are analyzed in PURPLE.
     Streamline in pencil.
     Isotachs in green every 20 knots, starting with 50 knots.
     Axes of maximum wind flow: 50 kts, using broad solid purple arrows with all speed maxima labeled.
     Difluent regions: Broad purple zigzag (WWWWW) lines.
     Areas of speed divergence: Broad purple wavy lines (speed divergence 30 kts/90NM)
     Height falls in purple (300mb only) using same procedures as listed under 500mb height falls above.
     Warm and cold pockets: Warm - purple W/ Cold - purple K
     Example of a 300mb Analysis.

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