WEEK 3: 10 SEP 2019 Reminder: Class notes UTC Time (suppl. Lecture notes) Weather review – Hurricane Florence, TS Olivia; Weather observations (suppl. Lecture notes) Weather Station model Weather Station Model; (in class assignment) Weather Maps Introduction to Tornadoes (suppl. Lecture notes)

Weather Symbols and Maps

Station model 80 021 -23 63

Weather Symbols

Sky Symbols

Wind Symbols

Pressure Tendency

Station model 80 021 -23 63

Station model 80 021 -23 63 Temperature Surface: ºF Upper air: ºC

Station model 80 021 -23 63 Dew point temperature Surface: ºF Upper air: ºC

Station model 80 021 -23 63 Total sky cover ** Depicted by shading in circle

Station model 80 021 -23 63 Current weather conditions ** If blank, “no weather”

Station model 80 021 -23 63 Wind direction – of wind toward center

Station model 80 021 -23 63 Wind speed Long barb = 10 knots Short barb = 5 knots Flag = 50 knots ** Notice range of wind speeds (i.e., 28-32 knots)

Station model 80 021 -23 63 Sea level pressure **If first number is 5 or greater, then place 9 in front --Otherwise, place 10 in front **Place decimal point between last two numbers Example above: 1002.1 hPa

Station model 80 021 -23 63 Change in surface pressure during last 3 hours ** In tenths of mb ** Line describes how pressure changes over time from left to right

76 953 +16 65 Example 1 Temperature: 76 ºF Dew point: 65 ºF Sky cover: Completely overcast Current weather: Light rain Wind direction and speed: Southwest at 15 knots Sea level pressure: 995.3 mb Pressure tendency: Increase of 1.6 mb; rising steadily 76 953 +16 65

Example 2 Temperature: 10ºF Dew point: 8ºF Sky cover: 7/10 or 8/10 Current weather: Snow shower Wind direction and speed: North at 3-7 knots Sea level pressure: 1010.5 mb Pressure tendency: Decrease of 0.4 mb; falling, then steady

Weather Station Model In-class assignment

WEATHER MAPS

High & Low Pressure Systems Air pressure Patterns are main organizing feature Circulation in Northern Hemisphere Clockwise around Highs (H) CCW around Lows (L) Clouds & Precip around Lows Temperature patterns result from latitude, wind flow and cloud cover

Boundary between Different Air Masses Plotting Fronts Boundary between Different Air Masses Types of Fronts

Weather Maps

ISOPLETHS

Contour Maps

Contour Maps

Contour Maps

Weather Maps

Weather Maps

Weather Maps

Weather Maps

ISOTACHS

ISOTACHS

ISOHYET

Isallobar = pressure change per time Isotherm = temperature* ISOPLETHS Connects all points that have the same value Iso = equal (Greek) Also called “Isolines” Types Isobar = pressure* Isallobar = pressure change per time Isotherm = temperature* Isohyet = rainfall* Isonif = snowfall isotach = wind speed*

READING ASSIGNMENT For weeks 3 & 4: TUE, SEP. 10th ,17th Pielke and Pielke; Up through Chp 1 (Point of view: societal impacts should partially dictate the direction of scientific research and governmental response) Simmons and Sutter: Foreward and Chp 1(Point of view: societal impacts should partially dictate the direction of scientific research and governmental response) Williams: Chp 2; Chapter 3 (up through p. 36); Chapter 5, 63-72; Chapter 9 (Hurricanes) Zebrowski: Chapter 2 (Point of view; how the scientists do research--the scientific method)