What’s an S/W? Is that a shortwave? What does a shortwave look like on one of the maps that get posted?

We’ll start with the first question. Yes, S/W (sometimes written SW– which is obviously confusing to those of us who also care about directions– which is, well, all mets) means “shortwave.” A shortwave is essentially a “kink” in the large-scale upper level trough/ridge system.

For examples, I’ve pulled some output from the last 84-hr NAM run. Below is the 300 mb map at 30-36-42 hours from model spin-up (18Z Wed, 00Z Thu, 06Z Thu) which is Wednesday afternoon through about 1 AM Thursday AM. Color contours are wind speed, arrows are wind direction (length corresponds to magnitude) and the line contours are height contours (you can think of higher heights being higher pressure and lower heights being lower pressure– they are the height in geopotential meters that you find the 300 mb pressure level for a given X/Y (lat/lon) location).

There are a couple prominent shortwaves in the trough. One begins in ID and makes its way down to the NE/CO/WY border by the end of the run. The one we’ll focus on begins in KS/OK and makes its way up through IL into IN by 42hr.

Here’s a better look; from now on we’ll freeze at 36hr (00Z Thursday).

You can see the counterclockwise kink in the white (height) contours very well in this picture. You can see hints of it as far north as Minnesota and it almost parallels the Mississippi River all the way down to the gulf coast. Shortwaves (like this one) are usually formed by cool pools aloft and upper level fronts.

There are phenomenon associated with shortwaves that are evident at all layers in the atmosphere. Next is the 500mb map, which shows color contours of “vorticity.” Vorticity is essentially the amount of rotation an infinitesimal parcel of fluid has.

We can see a brightly colored area right in the region of the most “kinkage.” This is conceptually expected. The smaller radius of curvature at the bottom of the kink implies more vorticity since the an air parcel following the curved contours would need to rotate more than one following non-curved contours. Also, from now on I will refer to positive and negative vorticity. In this graph the “warmer” the colors (reds, oranges, and yellows) the more positive the vorticity. The way I tell most people to keep it straight is (in the NH) positive vorticity = good for rising motion = exciting weather (storms) = cyclonic = counterclockwise. On the downwind (eastern) side of the kink we get what is called “positive vorticity advection.” For those not familiar with advection, it is (essentially) the transport of a fluid property from location X to location Y. Here, we see the wind is blowing from Kansas through Arkansas and up the Ohio River. Positive vorticity advection is occurring around the Mississippi River (east of the big yellow bulls-eye) because the highly positive vorticity is being transported (via wind) eastward. In simplistic terms, advection can be thought of as the derivative (d/dx) or gradient of a field. If you have no gradient, you have no advection because you’ll just replace your parcel of air with another parcel of air with the same properties (vorticity, temperature, moisture, whatever property you want to advect). However, if the gradient is steep, then you will notice rapid changes as air travels to and then through your location because you are transporting air that is very different than what was previously in the region (high magnitude of advection).

This kink also causes another type of advection. Temperature advection. Meteorologists typically like to look at the 850 mb map to see this.

Here we same the same thing as vorticity. The color contours are temperature (warm colors are higher) and the white arrows are wind. In the black circle we see the wind “blowing” from warmer air to cold. Therefore, in regions like Arkansas, warm air advection (WAA) is occurring due to the shortwave– it’s causing warm air to be transported into a region where cooler air previously existed. Over time we expect to see temperatures rise. You are also seeing cold air being advected BEHIND the kink (KS/OK). This is called cold air advection (CAA). The WAA and CAA are what cause the thermal gradients more commonly interpreted as “warm fronts” and “cold fronts.”

So why is this all important? Well, in very simple forecasting terms, both WAA and positive vorticity advection (PVA) are associated with rising motion in the atmosphere (there are a lot of very complicated dynamical reasons this is the case; I have spent 6+ years learning all of this so it’s not something I can really delve into the “why” of on a blog). Not surprisingly, our shortwave is associated with both of these lifting mechanisms– lifting implies latent heat release through condensation and we typically see precipitation. Well do we? I’ll show one last chart. This is the surface map with QPF (precipitation) in color contours.

Voila. We have precipitation in the area of our shortwave! Now there’s a couple small issues with this. One, this precip is actually the accumulated rainfall over the past 6 hours (30hr-36hr). For it to “line up better” with our other charts above we would have to average the “before” and “after” (36hr-42hr) QPF to get one centered on 36hr. Two, the shortwave is part of a complicated system; it may the main driver, but it isn’t working alone and is always interacting with the atmosphere. For instance; we see the heaviest precipitation a bit further south than we’d expect given the vorticity plots. Well from just a quick glance at the maps (don’t worry– I didn’t point this out earlier so as not to confuse the topic at hand) there is some upper level jet divergence near the Gulf Coast which is enhancing the vertical motion (and hence rainfall). We also expect QPF to be highest near the warm Gulf waters because there is a greater moisture flux from the surface to the atmosphere there (which means higher vapor pressures, more rapid condensation and more precipitation).

If all these features persist as the shortwave moves and they continue to work the way they need to; we increase baroclinic instability: instability driven by temperature gradients in the atmosphere (which is a result of the WAA/CAA as well as the rising motion induced by factors such as vorticity advection). This creates an energy source that can intensify tiny shortwaves into powerful mid-latitude cyclones. Now, this is an extremely simplified conceptual model; and isn’t EXACTLY how big nor’easters form (which is obviously more complicated; otherwise you could get a met degree in 6 weeks ); but it should give everyone a broad understanding of the dynamics at play and how to spot a few of these features on either weather maps or model output.

There are a solutions regarding using the object model floating around the web, but one easy way I figured was to actually draw a vertically-hatched pattern in a painting program and then use IT as the “picture fill.”

Directions?

1.) Save the four (they are four separate) pictures below (or, more easily, the zip file) to your hard drive. Unzip/save somewhere you’ll remember.
2.) In Excel, create your chart; then right click on the bar/area you want filled with the hatching and click “format data point.”
3.) Click on “Fill,” then “Picture or texture fill,” then “Insert from… File.” Navigate to your file. Click on it.
4.) Voila, simple, easy, hatching.

While I was enamored with 1Password (and still am) the biggest hurdle to it’s adoption is that I own a PC and a Mac (remember?). Syncing the password database between computers is therefore a necessity, and syncing across operating systems (XP/7 to OS X and vice versa) even moreso. This was certainly doable with KeePass and KeePassX, although KeePassX didn’t support a global auto-type hotkey. A password storage system is rendered virtually useless if every single time I have to log into a different web page I have to bring up the KeePassX window; copy my information to the clipboard, bring the focus back to FireFox, and type it in. Well, good news! An updated (albeit currently unsupported) version of KeePass (based on v0.4.1) adds auto-type functionality!

So now that we have auto-type everywhere, how to sync so we can use our KeePass databases everywhere we go? Well it’s very easy.

1.) If you aren’t using Dropbox yet, start. Go to Dropbox, set up and account, download the software, and set it up so both (or however many you have) machines are synced. Create a folder somewhere in your Dropbox scheme (by default under Documents -> My Dropbox) called “KeePass.”
2.) Download and install KeePassX (Mac) here. Download and install KeePass Classic (Windows) here. Note: We need to download the “classic” version because KeePassX still uses the old .kdb format instead of the new .kdbx. While we can set triggers in the new Windows version to automatically pop out a .kdb version AND a .kdbx every time we edit a password on that computer, we can’t edit .kdb’s on the Mac and automatically import them into KeePass on the Windows box. And that makes syncing unfun.
3.) On the Windows box (you can do it the other direction, too, but I found the Windows KeePass interface to be a bit more intuitive) open KeePass and create a new database. Set a “master password” and repeat. Don’t let this password suck too much; after all, you’ll be MINIMIZING the number of passwords you have to remember– at the very least you can do a good job coming up with a solid password that gives access to– well– everything else. Use a key file, too, if you’d like, but I find it unnecessary; it’s always something you can add later.
4.) Click “save as” and save the .kdb file to the directory you previously created within your dropbox scheme. Temporarily close KeePass on Windows and open KeePassX on the Mac. Browse to the newly created (and synced) database file and click open. Enter password. Try creating a few keys. Save. Close.
5.) Re-open the Windows version. Now you should only be prompted for the password (no browsing needed) and you should see your KeePass passwords in Windows. Congrats; you’ve done the heavy lifting!

A few notes; this will work between a PC/Linux or Linux/Mac as well. The same general steps apply although you will need the KeePass repo for your Linux flavor or you can compile from source. If you are a Linux user, I figure you probably don’t really need directions on how to do that. Second, KeePass (and therefore KeePassX) don’t automatically update the database while the program is running. Therefore, when you are adding keys be careful not to add different keys on different computers while both are still open. Dropbox handles conflicts well but you will lose some keys depending on what was open and what was being edited at the time. As a rule of thumb, when I first started migrating to KeePass I never had it running on more than one computer at a time. Once you have a stable database, it’s fine to have multiple instances going at once (it will typically ask to open in “read-only” anyways).

You can turn auto-type on and off by doing the following:
Windows: Tools -> Options -> Advanced tab -> Auto-Type button (lower right).
Mac: KeePassX -> Preferences -> Advanced

Some final notes to get auto-type running flawlessly on your computer. As a general practice, I had two lines to the comments of every key.

Auto-Type-Window: *balloflightning.com*

This aids KeePass/X in finding the window you want to auto-type in. I’ve found great success with the Firefox add-on “Hostname” which puts the domain name of the current web-site in the title bar. It may add a bit of clutter to your windows, but it provides you a surefire way to make sure KeePass/X is only auto-typing in the proper Firefox window/tab. The ‘*’ are wildcards, signifying KeePass/X will find whatever window has XXXXX balloflightning.com XXXXX in it. Obviously, you change the hostname between the ‘*’ to whatever key you are storing (i.e., paypal.com, ebay.com, etc.)

Auto-Type: {USERNAME}{TAB}{PASSWORD}{ENTER}

This is the custom sequence for the target window. {USERNAME} and {PASSWORD} are the stored username and password, {TAB} is… well… tab and {ENTER} is also self-explanatory. In some cases you may be forced to modify this (for example, I have to add a {TAB} after {USERNAME} every once in a while because the websites have a “click here to remember me” form.

Some people will find that in OS X, tabbing will result in certain portions of forms (checkboxes, radio buttons, dropdowns, etc.) being skipped. This creates a bit of a problem here because the sequences will then not match between Windows and Mac. Solution?

1.) Open System Preferences
2.) Go to Keyboard & Mouse
3.) Select “All controls” for full keyboard access

For a Firefox-only solution, you can also add / change the accessibility.tabfocus Firefox option via about:config to one of the following: 3 to be able to tab to form controls or 7 to be able to tab to everything

Simply closing the browser doesn’t work. In some cases deleting cookies doesn’t work. Whatever the problem ACUALLY is, but browser illiterate self found a simple, painless workaround until Gmail figures out what the problem is.

1.) Navigate to www.google.com
2.) Move cursor to top of page (this should cause the on-site toolbar to appear.
3.) Click “log out”
4.) Click “log in.” Enter login info.
5.) Click Gmail.

Voila. So far the pesky loop only happens with the www.mail.google.com connection, not www.google.com. Feel free to enlighten me as to why that is. Seriously.

I had tried to sync my GMail account once-upon-a-time, but decided it wasn’t worth the potential hassle. What hassle, I don’t remember– but in any event, I remember it was extremely easy to get it up and running using POP. However, this time around I decided IMAP was the way to go. Over the last few years I have slowly devolved into someone who uses GMail as my big e-mail cloud in the sky– that is, I want to be able to access an identical account (same inbox, sent, drafts, etc.) from anywhere (Macbook, PC, office, iPhone). IMAP should give me that ability.

Well, once I set up Mail to play nice with my Google account I noticed signficant slowdowns. I mean really, really slow. Like sending an e-mail that said “hello world!” took five minutes as the Apple pinwheel spun frantically. It seems like this a common occurrence with Mail 3.x and Leopard/Snow Leopard but there seem to be very few answers. I did end up finding one in the dusty corner of the internet.

It appears that Apple Mail has an issue with big attachments. I mean really big attachments. Like 20 MB big. Get rid of them, and it solves the problem. How do you do it? Well, there are two ways…

The easy way (tested by yours truly):

1.) Delete your IMAP account from within Mail by going to “Mail” -> “Preferences” and then clicking the little minus button below the account names. NOTE: I’m pretty sure this is foolproof with IMAP, but please, please make sure you are not deleting your e-mails from the server when you download them to your computer, because if you do that and then delete this account, well, you’ll lose your e-mails.

2.) Go into finder and delete the folder ~/Library/Mail/IMAP–/ or thereabouts.

3.) Go back into Mail, click on “Mail” -> “Preferences” and then the plus icon. Create your IMAP account as you did previously (make sure “create my account automatically” is unchecked or you will end up just creating a POP account with the default settings). This time, unclick “bring this account online” at the end of the creation process.

4.) Go back into “Mail” -> “Preferences,” click on your GMail – IMAP account, then click on the advanced tab. Uncheck “compact mailboxes automatically” and MOST IMPORTANTLY set the offline viewing preference to keep “all messages but omit attachments.”

5.) Set account to “online” and Mail will re-download all your e-mails; however e-mails and e-mails alone– no attachments. Everything should be running at Mach speed again.

Now, this way has one main drawback. You aren’t storing any attachments on your within Mail; if you want to download them, you have to do so as the e-mail comes in. This isn’t a problem for me, since I download the attachments I feel are important to whatever folder they are needed in by default and therefore don’t need another copy clogging up my inbox. However, if this is of crucial importance you can try the next step (at your own risk).

The hard way (I haven’t confirmed this works, but this would allow you to keep most attachments offline; only the ones over 20 MB are deleted– courtesy of bebopper):

1.) Quit Mail (Force quit if you have to)

2.) In Finder, click “Go” -> “Go to Folder.” Type the following folder path (replacing with your GMail User Name): ~/Library/Mail/IMAP–/.OfflineCache

3.) Look through the cached messages in this invisible folder and see if there is one or more larger than 20MB.

4.) Drag the offending large messages to the Desktop or Trash. Restart Mail, and Mail should stop hating you.

Both of these are essentially band-aids, so hopefully Apple will get its act together and figure out exactly what is going on. This seems to be a problem that has arisen in later incarnations of 10.5 and into 10.6, so it’s something that should be of pressing importance to the development team as we speak.

1.) The printer is automatically selected to “use printer offline.”
2.) Upon deselecting “use printer offline,” the print status of any documents in the queue is changed to “Error – printing” at which point anything in the queue will hang.
3.) The printer will reset itself to “use printer offline” upon power cycle or OS reboot, therefore leading to an endless cycle of 1, 2, and 3.

It turns out my issue was in the IOGEAR USB hub I use. I’m not sure if Windows 7 is having trouble dealing with the drivers (it was working in XP about a week ago) or the hub is just flat-out fried. Either way, I’ve seen a lot of threads on Google with the same problem but lack a resolution. Here’s one more thing to try, even if it’s a “well, duh.” If that doesn’t work, it can’t hurt to go with the always popular “reinstall the driver.”

Yeah. Thanks Microsoft. Here’s how to get around that.

Download oscdimg and then drop oscdimg.exe file into C:\Windows\System32.

Start -> Run -> type “cmd” to open a command window.

In the command window, type “oscdimg.exe -u2 -bC:\PATH\expandedSetup\boot\etfsboot.com -h C:\PATH\expandedSetup C:\PATH\Win7.iso” replacing C:\PATH\ with your actual path to the downloaded files.

You should now have an .iso file in that directory; burn a DVD using your favorite software (I used CDBurnerXP, but it’s old).

Restart and boot from the CD (specific to individual motherboards, my Biostar is F9, some are F8, some are the “Del” key). You should see something to the effect of “Press XX to select boot drive.” Press and select your DVD drive and follow the Windows 7 installation from there.

Thanks SIW2.

Unplug all peripherals except PS/2 mouse and keyboard.

Go into BIOS. Disable “USB controller.”

Remove/disable video card if you are bypassing the on-board graphics.

Boot the install disk.

Wait.

Wait.

Wait. (Seriously, like 15 minutes).

Follow install.

Reset everything back to “normal” following the installation. Apparently Windows 7 is having trouble with the drivers during installation, but does a reasonably good job downloading them afterwards.

Heterosexual.

We could not complete your iTunes Store request.
An unknown error occured (-4).

There was an error in the iTunes Store. Please try again later.

Apparently, Rich Hauck has the solution.

1. Quit iTunes
2. Navigate to System/Library/Extensions and delete AppleMobileDevice.kext (you may be prompted to enter your admin information)
3. Restart iTunes

Directions are also official via Apple Support.